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authorGeorg Brandl <georg@python.org>2007-08-15 14:28:22 +0000
committerGeorg Brandl <georg@python.org>2007-08-15 14:28:22 +0000
commite395d9483cba40d328a49a42c75b79e3ef1dd770 (patch)
tree3a26ee506c46066878a5705f213c08e17e6ce6a1
parent4e5cab59a9f2efc1f3cece227b49f79c3c830bbd (diff)
downloadcpython-e395d9483cba40d328a49a42c75b79e3ef1dd770.tar.gz
Move the 3k reST doc tree in place.
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-rw-r--r--Doc/whatsnew/3.0.rst161
423 files changed, 131199 insertions, 0 deletions
diff --git a/Doc/ACKS.txt b/Doc/ACKS.txt
new file mode 100644
index 0000000000..f695403eba
--- /dev/null
+++ b/Doc/ACKS.txt
@@ -0,0 +1,196 @@
+Contributors to the Python Documentation
+----------------------------------------
+
+This file lists people who have contributed in some way to the Python
+documentation. It is probably not complete -- if you feel that you or
+anyone else should be on this list, please let us know (send email to
+docs@python.org), and we'll be glad to correct the problem.
+
+* Aahz
+* Michael Abbott
+* Steve Alexander
+* Jim Ahlstrom
+* Fred Allen
+* A. Amoroso
+* Pehr Anderson
+* Oliver Andrich
+* Jesús Cea Avión
+* Daniel Barclay
+* Chris Barker
+* Don Bashford
+* Anthony Baxter
+* Bennett Benson
+* Jonathan Black
+* Robin Boerdijk
+* Michal Bozon
+* Aaron Brancotti
+* Georg Brandl
+* Keith Briggs
+* Lee Busby
+* Lorenzo M. Catucci
+* Carl Cerecke
+* Mauro Cicognini
+* Gilles Civario
+* Mike Clarkson
+* Steve Clift
+* Dave Cole
+* Matthew Cowles
+* Jeremy Craven
+* Andrew Dalke
+* Ben Darnell
+* L. Peter Deutsch
+* Robert Donohue
+* Fred L. Drake, Jr.
+* Jeff Epler
+* Michael Ernst
+* Blame Andy Eskilsson
+* Carey Evans
+* Martijn Faassen
+* Carl Feynman
+* Hernán Martínez Foffani
+* Stefan Franke
+* Jim Fulton
+* Peter Funk
+* Lele Gaifax
+* Matthew Gallagher
+* Ben Gertzfield
+* Nadim Ghaznavi
+* Jonathan Giddy
+* Shelley Gooch
+* Nathaniel Gray
+* Grant Griffin
+* Thomas Guettler
+* Anders Hammarquist
+* Mark Hammond
+* Harald Hanche-Olsen
+* Manus Hand
+* Gerhard Häring
+* Travis B. Hartwell
+* Tim Hatch
+* Janko Hauser
+* Bernhard Herzog
+* Magnus L. Hetland
+* Konrad Hinsen
+* Stefan Hoffmeister
+* Albert Hofkamp
+* Gregor Hoffleit
+* Steve Holden
+* Thomas Holenstein
+* Gerrit Holl
+* Rob Hooft
+* Brian Hooper
+* Randall Hopper
+* Michael Hudson
+* Eric Huss
+* Jeremy Hylton
+* Roger Irwin
+* Jack Jansen
+* Philip H. Jensen
+* Pedro Diaz Jimenez
+* Kent Johnson
+* Lucas de Jonge
+* Andreas Jung
+* Robert Kern
+* Jim Kerr
+* Jan Kim
+* Greg Kochanski
+* Guido Kollerie
+* Peter A. Koren
+* Daniel Kozan
+* Andrew M. Kuchling
+* Dave Kuhlman
+* Erno Kuusela
+* Detlef Lannert
+* Piers Lauder
+* Glyph Lefkowitz
+* Marc-André Lemburg
+* Ulf A. Lindgren
+* Everett Lipman
+* Mirko Liss
+* Martin von Löwis
+* Fredrik Lundh
+* Jeff MacDonald
+* John Machin
+* Andrew MacIntyre
+* Vladimir Marangozov
+* Vincent Marchetti
+* Laura Matson
+* Daniel May
+* Doug Mennella
+* Paolo Milani
+* Skip Montanaro
+* Paul Moore
+* Ross Moore
+* Sjoerd Mullender
+* Dale Nagata
+* Ng Pheng Siong
+* Koray Oner
+* Tomas Oppelstrup
+* Denis S. Otkidach
+* Zooko O'Whielacronx
+* William Park
+* Joonas Paalasmaa
+* Harri Pasanen
+* Bo Peng
+* Tim Peters
+* Christopher Petrilli
+* Justin D. Pettit
+* Chris Phoenix
+* François Pinard
+* Paul Prescod
+* Eric S. Raymond
+* Edward K. Ream
+* Sean Reifschneider
+* Bernhard Reiter
+* Armin Rigo
+* Wes Rishel
+* Jim Roskind
+* Guido van Rossum
+* Donald Wallace Rouse II
+* Nick Russo
+* Chris Ryland
+* Constantina S.
+* Hugh Sasse
+* Bob Savage
+* Scott Schram
+* Neil Schemenauer
+* Barry Scott
+* Joakim Sernbrant
+* Justin Sheehy
+* Michael Simcich
+* Ionel Simionescu
+* Gregory P. Smith
+* Roy Smith
+* Clay Spence
+* Nicholas Spies
+* Tage Stabell-Kulo
+* Frank Stajano
+* Anthony Starks
+* Greg Stein
+* Peter Stoehr
+* Mark Summerfield
+* Reuben Sumner
+* Kalle Svensson
+* Jim Tittsler
+* Ville Vainio
+* Martijn Vries
+* Charles G. Waldman
+* Greg Ward
+* Barry Warsaw
+* Corran Webster
+* Glyn Webster
+* Bob Weiner
+* Eddy Welbourne
+* Mats Wichmann
+* Gerry Wiener
+* Timothy Wild
+* Collin Winter
+* Blake Winton
+* Dan Wolfe
+* Steven Work
+* Thomas Wouters
+* Ka-Ping Yee
+* Rory Yorke
+* Moshe Zadka
+* Milan Zamazal
+* Cheng Zhang
diff --git a/Doc/Makefile b/Doc/Makefile
new file mode 100644
index 0000000000..955fb68b14
--- /dev/null
+++ b/Doc/Makefile
@@ -0,0 +1,62 @@
+#
+# Makefile for Python documentation
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+#
+
+# You can set these variables from the command line.
+PYTHON ?= python
+SVNROOT ?= http://svn.python.org/projects
+SPHINXOPTS ?=
+
+ALLSPHINXOPTS = -b$(BUILDER) -dbuild/doctrees $(SPHINXOPTS) . build/$(BUILDER)
+
+.PHONY: help checkout update build html web htmlhelp clean
+
+help:
+ @echo "Please use \`make <target>' where <target> is one of"
+ @echo " html to make standalone HTML files"
+ @echo " web to make file usable by Sphinx.web"
+ @echo " htmlhelp to make HTML files and a HTML help project"
+
+checkout:
+ @if [ ! -d tools/sphinx ]; then \
+ echo "Checking out Sphinx..."; \
+ svn checkout $(SVNROOT)/doctools/trunk/sphinx tools/sphinx; \
+ fi
+ @if [ ! -d tools/docutils ]; then \
+ echo "Checking out Docutils..."; \
+ svn checkout $(SVNROOT)/external/docutils-0.4/docutils tools/docutils; \
+ fi
+ @if [ ! -d tools/pygments ]; then \
+ echo "Checking out Pygments..."; \
+ svn checkout $(SVNROOT)/external/Pygments-0.8.1/pygments tools/pygments; \
+ fi
+
+update:
+ svn update tools/sphinx
+ svn update tools/docutils
+ svn update tools/pygments
+
+build: checkout
+ mkdir -p build/$(BUILDER) build/doctrees
+ $(PYTHON) tools/sphinx-build.py $(ALLSPHINXOPTS)
+ @echo
+
+html: BUILDER = html
+html: build
+ @echo "Build finished. The HTML pages are in build/html."
+
+web: BUILDER = web
+web: build
+ @echo "Build finished; now you can run"
+ @echo " PYTHONPATH=tools $(PYTHON) -m sphinx.web build/web"
+ @echo "to start the server."
+
+htmlhelp: BUILDER = htmlhelp
+htmlhelp: build
+ @echo "Build finished; now you can run HTML Help Workshop with the" \
+ "build/hhp/pydoc.hhp project file."
+
+clean:
+ -rm -rf build/*
+ -rm -rf tools/sphinx
diff --git a/Doc/README.txt b/Doc/README.txt
new file mode 100644
index 0000000000..c566a4a28c
--- /dev/null
+++ b/Doc/README.txt
@@ -0,0 +1,121 @@
+Python Documentation README
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This directory contains the reStructuredText (reST) sources to the Python
+documentation. You don't need to build them yourself, prebuilt versions are
+available at http://docs.python.org/download/.
+
+Documentation on the authoring Python documentation, including information about
+both style and markup, is available in the "Documenting Python" chapter of the
+documentation. There's also a chapter intended to point out differences to
+those familiar with the previous docs written in LaTeX.
+
+
+Building the docs
+=================
+
+You need to install Python 2.5 or higher; the toolset used to build the docs are
+written in Python. The toolset used to build the documentation is called
+*Sphinx*, it is not included in this tree, but maintained separately in the
+Python Subversion repository. Also needed are Jinja, a templating engine
+(included in Sphinx as a Subversion external), and optionally Pygments, a code
+highlighter.
+
+
+Using make
+----------
+
+Luckily, a Makefile has been prepared so that on Unix, provided you have
+installed Python and Subversion, you can just run ::
+
+ make html
+
+to check out the necessary toolset in the `tools/` subdirectory and build the
+HTML output files. To view the generated HTML, point your favorite browser at
+the top-level index `build/html/index.html` after running "make".
+
+Available make targets are:
+
+ * "html", which builds standalone HTML files for offline viewing.
+
+ * "web", which builds files usable with the Sphinx.web application (used to
+ serve the docs online at http://docs.python.org/).
+
+ * "htmlhelp", which builds HTML files and a HTML Help project file usable to
+ convert them into a single Compiled HTML (.chm) file -- these are popular
+ under Microsoft Windows, but very handy on every platform.
+
+ To create the CHM file, you need to run the Microsoft HTML Help Workshop
+ over the generated project (.hhp) file.
+
+A "make update" updates the Subversion checkouts in `tools/`.
+
+
+Without make
+------------
+
+You'll need to checkout the Sphinx package to the `tools/` directory::
+
+ svn co http://svn.python.org/projects/doctools/trunk/sphinx tools/sphinx
+
+Then, you need to install Docutils 0.4 (the SVN snapshot won't work), either
+by checking it out via ::
+
+ svn co http://svn.python.org/projects/external/docutils-0.4/docutils tools/docutils
+
+or by installing it from http://docutils.sf.net/.
+
+You can optionally also install Pygments, either as a checkout via ::
+
+ svn co http://svn.python.org/projects/external/Pygments-0.8.1/pygments tools/pygments
+
+or from PyPI at http://pypi.python.org/pypi/Pygments.
+
+
+Then, make an output directory, e.g. under `build/`, and run ::
+
+ python tools/sphinx-build.py -b<builder> . build/<outputdirectory>
+
+where `<builder>` is one of html, web or htmlhelp (for explanations see the make
+targets above).
+
+
+Contributing
+============
+
+For bugs in the content, the online version at http://docs.python.org/ has a
+"suggest change" facility that can be used to correct errors in the source text
+and submit them as a patch to the maintainers.
+
+Bugs in the toolset should be reported in the Python bug tracker at
+http://bugs.python.org/.
+
+You can also send a mail to the Python Documentation Team at docs@python.org,
+and we will process your request as soon as possible.
+
+If you want to help the Documentation Team, you are always welcome. Just send
+a mail to docs@python.org.
+
+
+Copyright notice
+================
+
+The Python source is copyrighted, but you can freely use and copy it
+as long as you don't change or remove the copyright notice:
+
+----------------------------------------------------------------------
+Copyright (c) 2000-2007 Python Software Foundation.
+All rights reserved.
+
+Copyright (c) 2000 BeOpen.com.
+All rights reserved.
+
+Copyright (c) 1995-2000 Corporation for National Research Initiatives.
+All rights reserved.
+
+Copyright (c) 1991-1995 Stichting Mathematisch Centrum.
+All rights reserved.
+
+See the file "license.rst" for information on usage and redistribution
+of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+----------------------------------------------------------------------
diff --git a/Doc/TODO.txt b/Doc/TODO.txt
new file mode 100644
index 0000000000..c8d3501bd6
--- /dev/null
+++ b/Doc/TODO.txt
@@ -0,0 +1,6 @@
+To do
+=====
+
+* split very large files and add toctrees
+* finish "Documenting Python"
+* care about XXX comments
diff --git a/Doc/about.rst b/Doc/about.rst
new file mode 100644
index 0000000000..d3ce2dd0ae
--- /dev/null
+++ b/Doc/about.rst
@@ -0,0 +1,33 @@
+=====================
+About these documents
+=====================
+
+
+These documents are generated from `reStructuredText
+<http://docutils.sf.net/rst.html>`_ sources by *Sphinx*, a document processor
+specifically written for the Python documentation.
+
+In the online version of these documents, you can submit comments and suggest
+changes directly on the documentation pages.
+
+Development of the documentation and its toolchain takes place on the
+docs@python.org mailing list. We're always looking for volunteers wanting
+to help with the docs, so feel free to send a mail there!
+
+Many thanks go to:
+
+* Fred L. Drake, Jr., the creator of the original Python documentation toolset
+ and writer of much of the content;
+* the `docutils <http://docutils.sf.net/>`_ project for creating
+ reStructuredText and the docutils suite;
+* Fredrik Lundh for his `Alternative Python Reference
+ <http://effbot.org/zone/pyref.htm>`_ project from which Sphinx got many good
+ ideas.
+
+See :ref:`reporting-bugs` for information how to report bugs in Python itself.
+
+.. including the ACKS file here so that it can be maintained separately
+.. include:: ACKS.txt
+
+It is only with the input and contributions of the Python community
+that Python has such wonderful documentation -- Thank You!
diff --git a/Doc/bugs.rst b/Doc/bugs.rst
new file mode 100644
index 0000000000..f8f75c21b8
--- /dev/null
+++ b/Doc/bugs.rst
@@ -0,0 +1,59 @@
+.. _reporting-bugs:
+
+************************
+Reporting Bugs in Python
+************************
+
+Python is a mature programming language which has established a reputation for
+stability. In order to maintain this reputation, the developers would like to
+know of any deficiencies you find in Python.
+
+If you find errors in the documentation, please use either the "Add a comment"
+or the "Suggest a change" features of the relevant page in the most recent
+online documentation at http://docs.python.org/.
+
+All other bug reports should be submitted via the Python Bug Tracker
+(http://bugs.python.org/). The bug tracker offers a Web form which allows
+pertinent information to be entered and submitted to the developers.
+
+The first step in filing a report is to determine whether the problem has
+already been reported. The advantage in doing so, aside from saving the
+developers time, is that you learn what has been done to fix it; it may be that
+the problem has already been fixed for the next release, or additional
+information is needed (in which case you are welcome to provide it if you can!).
+To do this, search the bug database using the search box on the top of the page.
+
+If the problem you're reporting is not already in the bug tracker, go back to
+the Python Bug Tracker. If you don't already have a tracker account, select the
+"Register" link in the sidebar and undergo the registration procedure.
+Otherwise, if you're not logged in, enter your credentials and select "Login".
+It is not possible to submit a bug report anonymously.
+
+Being now logged in, you can submit a bug. Select the "Create New" link in the
+sidebar to open the bug reporting form.
+
+The submission form has a number of fields. For the "Title" field, enter a
+*very* short description of the problem; less than ten words is good. In the
+"Type" field, select the type of your problem; also select the "Component" and
+"Versions" to which the bug relates.
+
+In the "Change Note" field, describe the problem in detail, including what you
+expected to happen and what did happen. Be sure to include whether any
+extension modules were involved, and what hardware and software platform you
+were using (including version information as appropriate).
+
+Each bug report will be assigned to a developer who will determine what needs to
+be done to correct the problem. You will receive an update each time action is
+taken on the bug.
+
+
+.. seealso::
+
+ `How to Report Bugs Effectively <http://www-mice.cs.ucl.ac.uk/multimedia/software/documentation/ReportingBugs.html>`_
+ Article which goes into some detail about how to create a useful bug report.
+ This describes what kind of information is useful and why it is useful.
+
+ `Bug Writing Guidelines <http://www.mozilla.org/quality/bug-writing-guidelines.html>`_
+ Information about writing a good bug report. Some of this is specific to the
+ Mozilla project, but describes general good practices.
+
diff --git a/Doc/c-api/abstract.rst b/Doc/c-api/abstract.rst
new file mode 100644
index 0000000000..1a1ff13dea
--- /dev/null
+++ b/Doc/c-api/abstract.rst
@@ -0,0 +1,997 @@
+.. highlightlang:: c
+
+
+.. _abstract:
+
+**********************
+Abstract Objects Layer
+**********************
+
+The functions in this chapter interact with Python objects regardless of their
+type, or with wide classes of object types (e.g. all numerical types, or all
+sequence types). When used on object types for which they do not apply, they
+will raise a Python exception.
+
+It is not possible to use these functions on objects that are not properly
+initialized, such as a list object that has been created by :cfunc:`PyList_New`,
+but whose items have not been set to some non-\ ``NULL`` value yet.
+
+
+.. _object:
+
+Object Protocol
+===============
+
+
+.. cfunction:: int PyObject_Print(PyObject *o, FILE *fp, int flags)
+
+ Print an object *o*, on file *fp*. Returns ``-1`` on error. The flags argument
+ is used to enable certain printing options. The only option currently supported
+ is :const:`Py_PRINT_RAW`; if given, the :func:`str` of the object is written
+ instead of the :func:`repr`.
+
+
+.. cfunction:: int PyObject_HasAttrString(PyObject *o, const char *attr_name)
+
+ Returns ``1`` if *o* has the attribute *attr_name*, and ``0`` otherwise. This
+ is equivalent to the Python expression ``hasattr(o, attr_name)``. This function
+ always succeeds.
+
+
+.. cfunction:: PyObject* PyObject_GetAttrString(PyObject *o, const char *attr_name)
+
+ Retrieve an attribute named *attr_name* from object *o*. Returns the attribute
+ value on success, or *NULL* on failure. This is the equivalent of the Python
+ expression ``o.attr_name``.
+
+
+.. cfunction:: int PyObject_HasAttr(PyObject *o, PyObject *attr_name)
+
+ Returns ``1`` if *o* has the attribute *attr_name*, and ``0`` otherwise. This
+ is equivalent to the Python expression ``hasattr(o, attr_name)``. This function
+ always succeeds.
+
+
+.. cfunction:: PyObject* PyObject_GetAttr(PyObject *o, PyObject *attr_name)
+
+ Retrieve an attribute named *attr_name* from object *o*. Returns the attribute
+ value on success, or *NULL* on failure. This is the equivalent of the Python
+ expression ``o.attr_name``.
+
+
+.. cfunction:: int PyObject_SetAttrString(PyObject *o, const char *attr_name, PyObject *v)
+
+ Set the value of the attribute named *attr_name*, for object *o*, to the value
+ *v*. Returns ``-1`` on failure. This is the equivalent of the Python statement
+ ``o.attr_name = v``.
+
+
+.. cfunction:: int PyObject_SetAttr(PyObject *o, PyObject *attr_name, PyObject *v)
+
+ Set the value of the attribute named *attr_name*, for object *o*, to the value
+ *v*. Returns ``-1`` on failure. This is the equivalent of the Python statement
+ ``o.attr_name = v``.
+
+
+.. cfunction:: int PyObject_DelAttrString(PyObject *o, const char *attr_name)
+
+ Delete attribute named *attr_name*, for object *o*. Returns ``-1`` on failure.
+ This is the equivalent of the Python statement: ``del o.attr_name``.
+
+
+.. cfunction:: int PyObject_DelAttr(PyObject *o, PyObject *attr_name)
+
+ Delete attribute named *attr_name*, for object *o*. Returns ``-1`` on failure.
+ This is the equivalent of the Python statement ``del o.attr_name``.
+
+
+.. cfunction:: PyObject* PyObject_RichCompare(PyObject *o1, PyObject *o2, int opid)
+
+ Compare the values of *o1* and *o2* using the operation specified by *opid*,
+ which must be one of :const:`Py_LT`, :const:`Py_LE`, :const:`Py_EQ`,
+ :const:`Py_NE`, :const:`Py_GT`, or :const:`Py_GE`, corresponding to ``<``,
+ ``<=``, ``==``, ``!=``, ``>``, or ``>=`` respectively. This is the equivalent of
+ the Python expression ``o1 op o2``, where ``op`` is the operator corresponding
+ to *opid*. Returns the value of the comparison on success, or *NULL* on failure.
+
+
+.. cfunction:: int PyObject_RichCompareBool(PyObject *o1, PyObject *o2, int opid)
+
+ Compare the values of *o1* and *o2* using the operation specified by *opid*,
+ which must be one of :const:`Py_LT`, :const:`Py_LE`, :const:`Py_EQ`,
+ :const:`Py_NE`, :const:`Py_GT`, or :const:`Py_GE`, corresponding to ``<``,
+ ``<=``, ``==``, ``!=``, ``>``, or ``>=`` respectively. Returns ``-1`` on error,
+ ``0`` if the result is false, ``1`` otherwise. This is the equivalent of the
+ Python expression ``o1 op o2``, where ``op`` is the operator corresponding to
+ *opid*.
+
+
+.. cfunction:: int PyObject_Cmp(PyObject *o1, PyObject *o2, int *result)
+
+ .. index:: builtin: cmp
+
+ Compare the values of *o1* and *o2* using a routine provided by *o1*, if one
+ exists, otherwise with a routine provided by *o2*. The result of the comparison
+ is returned in *result*. Returns ``-1`` on failure. This is the equivalent of
+ the Python statement ``result = cmp(o1, o2)``.
+
+
+.. cfunction:: int PyObject_Compare(PyObject *o1, PyObject *o2)
+
+ .. index:: builtin: cmp
+
+ Compare the values of *o1* and *o2* using a routine provided by *o1*, if one
+ exists, otherwise with a routine provided by *o2*. Returns the result of the
+ comparison on success. On error, the value returned is undefined; use
+ :cfunc:`PyErr_Occurred` to detect an error. This is equivalent to the Python
+ expression ``cmp(o1, o2)``.
+
+
+.. cfunction:: PyObject* PyObject_Repr(PyObject *o)
+
+ .. index:: builtin: repr
+
+ Compute a string representation of object *o*. Returns the string
+ representation on success, *NULL* on failure. This is the equivalent of the
+ Python expression ``repr(o)``. Called by the :func:`repr` built-in function and
+ by reverse quotes.
+
+
+.. cfunction:: PyObject* PyObject_Str(PyObject *o)
+
+ .. index:: builtin: str
+
+ Compute a string representation of object *o*. Returns the string
+ representation on success, *NULL* on failure. This is the equivalent of the
+ Python expression ``str(o)``. Called by the :func:`str` built-in function and
+ by the :keyword:`print` statement.
+
+
+.. cfunction:: PyObject* PyObject_Unicode(PyObject *o)
+
+ .. index:: builtin: unicode
+
+ Compute a Unicode string representation of object *o*. Returns the Unicode
+ string representation on success, *NULL* on failure. This is the equivalent of
+ the Python expression ``unicode(o)``. Called by the :func:`unicode` built-in
+ function.
+
+
+.. cfunction:: int PyObject_IsInstance(PyObject *inst, PyObject *cls)
+
+ Returns ``1`` if *inst* is an instance of the class *cls* or a subclass of
+ *cls*, or ``0`` if not. On error, returns ``-1`` and sets an exception. If
+ *cls* is a type object rather than a class object, :cfunc:`PyObject_IsInstance`
+ returns ``1`` if *inst* is of type *cls*. If *cls* is a tuple, the check will
+ be done against every entry in *cls*. The result will be ``1`` when at least one
+ of the checks returns ``1``, otherwise it will be ``0``. If *inst* is not a
+ class instance and *cls* is neither a type object, nor a class object, nor a
+ tuple, *inst* must have a :attr:`__class__` attribute --- the class relationship
+ of the value of that attribute with *cls* will be used to determine the result
+ of this function.
+
+ .. versionadded:: 2.1
+
+ .. versionchanged:: 2.2
+ Support for a tuple as the second argument added.
+
+Subclass determination is done in a fairly straightforward way, but includes a
+wrinkle that implementors of extensions to the class system may want to be aware
+of. If :class:`A` and :class:`B` are class objects, :class:`B` is a subclass of
+:class:`A` if it inherits from :class:`A` either directly or indirectly. If
+either is not a class object, a more general mechanism is used to determine the
+class relationship of the two objects. When testing if *B* is a subclass of
+*A*, if *A* is *B*, :cfunc:`PyObject_IsSubclass` returns true. If *A* and *B*
+are different objects, *B*'s :attr:`__bases__` attribute is searched in a
+depth-first fashion for *A* --- the presence of the :attr:`__bases__` attribute
+is considered sufficient for this determination.
+
+
+.. cfunction:: int PyObject_IsSubclass(PyObject *derived, PyObject *cls)
+
+ Returns ``1`` if the class *derived* is identical to or derived from the class
+ *cls*, otherwise returns ``0``. In case of an error, returns ``-1``. If *cls*
+ is a tuple, the check will be done against every entry in *cls*. The result will
+ be ``1`` when at least one of the checks returns ``1``, otherwise it will be
+ ``0``. If either *derived* or *cls* is not an actual class object (or tuple),
+ this function uses the generic algorithm described above.
+
+ .. versionadded:: 2.1
+
+ .. versionchanged:: 2.3
+ Older versions of Python did not support a tuple as the second argument.
+
+
+.. cfunction:: int PyCallable_Check(PyObject *o)
+
+ Determine if the object *o* is callable. Return ``1`` if the object is callable
+ and ``0`` otherwise. This function always succeeds.
+
+
+.. cfunction:: PyObject* PyObject_Call(PyObject *callable_object, PyObject *args, PyObject *kw)
+
+ Call a callable Python object *callable_object*, with arguments given by the
+ tuple *args*, and named arguments given by the dictionary *kw*. If no named
+ arguments are needed, *kw* may be *NULL*. *args* must not be *NULL*, use an
+ empty tuple if no arguments are needed. Returns the result of the call on
+ success, or *NULL* on failure. This is the equivalent of the Python expression
+ ``callable_object(*args, **kw)``.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyObject_CallObject(PyObject *callable_object, PyObject *args)
+
+ Call a callable Python object *callable_object*, with arguments given by the
+ tuple *args*. If no arguments are needed, then *args* may be *NULL*. Returns
+ the result of the call on success, or *NULL* on failure. This is the equivalent
+ of the Python expression ``callable_object(*args)``.
+
+
+.. cfunction:: PyObject* PyObject_CallFunction(PyObject *callable, char *format, ...)
+
+ Call a callable Python object *callable*, with a variable number of C arguments.
+ The C arguments are described using a :cfunc:`Py_BuildValue` style format
+ string. The format may be *NULL*, indicating that no arguments are provided.
+ Returns the result of the call on success, or *NULL* on failure. This is the
+ equivalent of the Python expression ``callable(*args)``. Note that if you only
+ pass :ctype:`PyObject \*` args, :cfunc:`PyObject_CallFunctionObjArgs` is a
+ faster alternative.
+
+
+.. cfunction:: PyObject* PyObject_CallMethod(PyObject *o, char *method, char *format, ...)
+
+ Call the method named *method* of object *o* with a variable number of C
+ arguments. The C arguments are described by a :cfunc:`Py_BuildValue` format
+ string that should produce a tuple. The format may be *NULL*, indicating that
+ no arguments are provided. Returns the result of the call on success, or *NULL*
+ on failure. This is the equivalent of the Python expression ``o.method(args)``.
+ Note that if you only pass :ctype:`PyObject \*` args,
+ :cfunc:`PyObject_CallMethodObjArgs` is a faster alternative.
+
+
+.. cfunction:: PyObject* PyObject_CallFunctionObjArgs(PyObject *callable, ..., NULL)
+
+ Call a callable Python object *callable*, with a variable number of
+ :ctype:`PyObject\*` arguments. The arguments are provided as a variable number
+ of parameters followed by *NULL*. Returns the result of the call on success, or
+ *NULL* on failure.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyObject_CallMethodObjArgs(PyObject *o, PyObject *name, ..., NULL)
+
+ Calls a method of the object *o*, where the name of the method is given as a
+ Python string object in *name*. It is called with a variable number of
+ :ctype:`PyObject\*` arguments. The arguments are provided as a variable number
+ of parameters followed by *NULL*. Returns the result of the call on success, or
+ *NULL* on failure.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: long PyObject_Hash(PyObject *o)
+
+ .. index:: builtin: hash
+
+ Compute and return the hash value of an object *o*. On failure, return ``-1``.
+ This is the equivalent of the Python expression ``hash(o)``.
+
+
+.. cfunction:: int PyObject_IsTrue(PyObject *o)
+
+ Returns ``1`` if the object *o* is considered to be true, and ``0`` otherwise.
+ This is equivalent to the Python expression ``not not o``. On failure, return
+ ``-1``.
+
+
+.. cfunction:: int PyObject_Not(PyObject *o)
+
+ Returns ``0`` if the object *o* is considered to be true, and ``1`` otherwise.
+ This is equivalent to the Python expression ``not o``. On failure, return
+ ``-1``.
+
+
+.. cfunction:: PyObject* PyObject_Type(PyObject *o)
+
+ .. index:: builtin: type
+
+ When *o* is non-*NULL*, returns a type object corresponding to the object type
+ of object *o*. On failure, raises :exc:`SystemError` and returns *NULL*. This
+ is equivalent to the Python expression ``type(o)``. This function increments the
+ reference count of the return value. There's really no reason to use this
+ function instead of the common expression ``o->ob_type``, which returns a
+ pointer of type :ctype:`PyTypeObject\*`, except when the incremented reference
+ count is needed.
+
+
+.. cfunction:: int PyObject_TypeCheck(PyObject *o, PyTypeObject *type)
+
+ Return true if the object *o* is of type *type* or a subtype of *type*. Both
+ parameters must be non-*NULL*.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: Py_ssize_t PyObject_Length(PyObject *o)
+ Py_ssize_t PyObject_Size(PyObject *o)
+
+ .. index:: builtin: len
+
+ Return the length of object *o*. If the object *o* provides either the sequence
+ and mapping protocols, the sequence length is returned. On error, ``-1`` is
+ returned. This is the equivalent to the Python expression ``len(o)``.
+
+
+.. cfunction:: PyObject* PyObject_GetItem(PyObject *o, PyObject *key)
+
+ Return element of *o* corresponding to the object *key* or *NULL* on failure.
+ This is the equivalent of the Python expression ``o[key]``.
+
+
+.. cfunction:: int PyObject_SetItem(PyObject *o, PyObject *key, PyObject *v)
+
+ Map the object *key* to the value *v*. Returns ``-1`` on failure. This is the
+ equivalent of the Python statement ``o[key] = v``.
+
+
+.. cfunction:: int PyObject_DelItem(PyObject *o, PyObject *key)
+
+ Delete the mapping for *key* from *o*. Returns ``-1`` on failure. This is the
+ equivalent of the Python statement ``del o[key]``.
+
+
+.. cfunction:: int PyObject_AsFileDescriptor(PyObject *o)
+
+ Derives a file-descriptor from a Python object. If the object is an integer or
+ long integer, its value is returned. If not, the object's :meth:`fileno` method
+ is called if it exists; the method must return an integer or long integer, which
+ is returned as the file descriptor value. Returns ``-1`` on failure.
+
+
+.. cfunction:: PyObject* PyObject_Dir(PyObject *o)
+
+ This is equivalent to the Python expression ``dir(o)``, returning a (possibly
+ empty) list of strings appropriate for the object argument, or *NULL* if there
+ was an error. If the argument is *NULL*, this is like the Python ``dir()``,
+ returning the names of the current locals; in this case, if no execution frame
+ is active then *NULL* is returned but :cfunc:`PyErr_Occurred` will return false.
+
+
+.. cfunction:: PyObject* PyObject_GetIter(PyObject *o)
+
+ This is equivalent to the Python expression ``iter(o)``. It returns a new
+ iterator for the object argument, or the object itself if the object is already
+ an iterator. Raises :exc:`TypeError` and returns *NULL* if the object cannot be
+ iterated.
+
+
+.. _number:
+
+Number Protocol
+===============
+
+
+.. cfunction:: int PyNumber_Check(PyObject *o)
+
+ Returns ``1`` if the object *o* provides numeric protocols, and false otherwise.
+ This function always succeeds.
+
+
+.. cfunction:: PyObject* PyNumber_Add(PyObject *o1, PyObject *o2)
+
+ Returns the result of adding *o1* and *o2*, or *NULL* on failure. This is the
+ equivalent of the Python expression ``o1 + o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Subtract(PyObject *o1, PyObject *o2)
+
+ Returns the result of subtracting *o2* from *o1*, or *NULL* on failure. This is
+ the equivalent of the Python expression ``o1 - o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Multiply(PyObject *o1, PyObject *o2)
+
+ Returns the result of multiplying *o1* and *o2*, or *NULL* on failure. This is
+ the equivalent of the Python expression ``o1 * o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Divide(PyObject *o1, PyObject *o2)
+
+ Returns the result of dividing *o1* by *o2*, or *NULL* on failure. This is the
+ equivalent of the Python expression ``o1 / o2``.
+
+
+.. cfunction:: PyObject* PyNumber_FloorDivide(PyObject *o1, PyObject *o2)
+
+ Return the floor of *o1* divided by *o2*, or *NULL* on failure. This is
+ equivalent to the "classic" division of integers.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyNumber_TrueDivide(PyObject *o1, PyObject *o2)
+
+ Return a reasonable approximation for the mathematical value of *o1* divided by
+ *o2*, or *NULL* on failure. The return value is "approximate" because binary
+ floating point numbers are approximate; it is not possible to represent all real
+ numbers in base two. This function can return a floating point value when
+ passed two integers.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyNumber_Remainder(PyObject *o1, PyObject *o2)
+
+ Returns the remainder of dividing *o1* by *o2*, or *NULL* on failure. This is
+ the equivalent of the Python expression ``o1 % o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Divmod(PyObject *o1, PyObject *o2)
+
+ .. index:: builtin: divmod
+
+ See the built-in function :func:`divmod`. Returns *NULL* on failure. This is
+ the equivalent of the Python expression ``divmod(o1, o2)``.
+
+
+.. cfunction:: PyObject* PyNumber_Power(PyObject *o1, PyObject *o2, PyObject *o3)
+
+ .. index:: builtin: pow
+
+ See the built-in function :func:`pow`. Returns *NULL* on failure. This is the
+ equivalent of the Python expression ``pow(o1, o2, o3)``, where *o3* is optional.
+ If *o3* is to be ignored, pass :cdata:`Py_None` in its place (passing *NULL* for
+ *o3* would cause an illegal memory access).
+
+
+.. cfunction:: PyObject* PyNumber_Negative(PyObject *o)
+
+ Returns the negation of *o* on success, or *NULL* on failure. This is the
+ equivalent of the Python expression ``-o``.
+
+
+.. cfunction:: PyObject* PyNumber_Positive(PyObject *o)
+
+ Returns *o* on success, or *NULL* on failure. This is the equivalent of the
+ Python expression ``+o``.
+
+
+.. cfunction:: PyObject* PyNumber_Absolute(PyObject *o)
+
+ .. index:: builtin: abs
+
+ Returns the absolute value of *o*, or *NULL* on failure. This is the equivalent
+ of the Python expression ``abs(o)``.
+
+
+.. cfunction:: PyObject* PyNumber_Invert(PyObject *o)
+
+ Returns the bitwise negation of *o* on success, or *NULL* on failure. This is
+ the equivalent of the Python expression ``~o``.
+
+
+.. cfunction:: PyObject* PyNumber_Lshift(PyObject *o1, PyObject *o2)
+
+ Returns the result of left shifting *o1* by *o2* on success, or *NULL* on
+ failure. This is the equivalent of the Python expression ``o1 << o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Rshift(PyObject *o1, PyObject *o2)
+
+ Returns the result of right shifting *o1* by *o2* on success, or *NULL* on
+ failure. This is the equivalent of the Python expression ``o1 >> o2``.
+
+
+.. cfunction:: PyObject* PyNumber_And(PyObject *o1, PyObject *o2)
+
+ Returns the "bitwise and" of *o1* and *o2* on success and *NULL* on failure.
+ This is the equivalent of the Python expression ``o1 & o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Xor(PyObject *o1, PyObject *o2)
+
+ Returns the "bitwise exclusive or" of *o1* by *o2* on success, or *NULL* on
+ failure. This is the equivalent of the Python expression ``o1 ^ o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Or(PyObject *o1, PyObject *o2)
+
+ Returns the "bitwise or" of *o1* and *o2* on success, or *NULL* on failure.
+ This is the equivalent of the Python expression ``o1 | o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceAdd(PyObject *o1, PyObject *o2)
+
+ Returns the result of adding *o1* and *o2*, or *NULL* on failure. The operation
+ is done *in-place* when *o1* supports it. This is the equivalent of the Python
+ statement ``o1 += o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceSubtract(PyObject *o1, PyObject *o2)
+
+ Returns the result of subtracting *o2* from *o1*, or *NULL* on failure. The
+ operation is done *in-place* when *o1* supports it. This is the equivalent of
+ the Python statement ``o1 -= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceMultiply(PyObject *o1, PyObject *o2)
+
+ Returns the result of multiplying *o1* and *o2*, or *NULL* on failure. The
+ operation is done *in-place* when *o1* supports it. This is the equivalent of
+ the Python statement ``o1 *= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceDivide(PyObject *o1, PyObject *o2)
+
+ Returns the result of dividing *o1* by *o2*, or *NULL* on failure. The
+ operation is done *in-place* when *o1* supports it. This is the equivalent of
+ the Python statement ``o1 /= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceFloorDivide(PyObject *o1, PyObject *o2)
+
+ Returns the mathematical floor of dividing *o1* by *o2*, or *NULL* on failure.
+ The operation is done *in-place* when *o1* supports it. This is the equivalent
+ of the Python statement ``o1 //= o2``.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceTrueDivide(PyObject *o1, PyObject *o2)
+
+ Return a reasonable approximation for the mathematical value of *o1* divided by
+ *o2*, or *NULL* on failure. The return value is "approximate" because binary
+ floating point numbers are approximate; it is not possible to represent all real
+ numbers in base two. This function can return a floating point value when
+ passed two integers. The operation is done *in-place* when *o1* supports it.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceRemainder(PyObject *o1, PyObject *o2)
+
+ Returns the remainder of dividing *o1* by *o2*, or *NULL* on failure. The
+ operation is done *in-place* when *o1* supports it. This is the equivalent of
+ the Python statement ``o1 %= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlacePower(PyObject *o1, PyObject *o2, PyObject *o3)
+
+ .. index:: builtin: pow
+
+ See the built-in function :func:`pow`. Returns *NULL* on failure. The operation
+ is done *in-place* when *o1* supports it. This is the equivalent of the Python
+ statement ``o1 **= o2`` when o3 is :cdata:`Py_None`, or an in-place variant of
+ ``pow(o1, o2, o3)`` otherwise. If *o3* is to be ignored, pass :cdata:`Py_None`
+ in its place (passing *NULL* for *o3* would cause an illegal memory access).
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceLshift(PyObject *o1, PyObject *o2)
+
+ Returns the result of left shifting *o1* by *o2* on success, or *NULL* on
+ failure. The operation is done *in-place* when *o1* supports it. This is the
+ equivalent of the Python statement ``o1 <<= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceRshift(PyObject *o1, PyObject *o2)
+
+ Returns the result of right shifting *o1* by *o2* on success, or *NULL* on
+ failure. The operation is done *in-place* when *o1* supports it. This is the
+ equivalent of the Python statement ``o1 >>= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceAnd(PyObject *o1, PyObject *o2)
+
+ Returns the "bitwise and" of *o1* and *o2* on success and *NULL* on failure. The
+ operation is done *in-place* when *o1* supports it. This is the equivalent of
+ the Python statement ``o1 &= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceXor(PyObject *o1, PyObject *o2)
+
+ Returns the "bitwise exclusive or" of *o1* by *o2* on success, or *NULL* on
+ failure. The operation is done *in-place* when *o1* supports it. This is the
+ equivalent of the Python statement ``o1 ^= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_InPlaceOr(PyObject *o1, PyObject *o2)
+
+ Returns the "bitwise or" of *o1* and *o2* on success, or *NULL* on failure. The
+ operation is done *in-place* when *o1* supports it. This is the equivalent of
+ the Python statement ``o1 |= o2``.
+
+
+.. cfunction:: PyObject* PyNumber_Int(PyObject *o)
+
+ .. index:: builtin: int
+
+ Returns the *o* converted to an integer object on success, or *NULL* on failure.
+ If the argument is outside the integer range a long object will be returned
+ instead. This is the equivalent of the Python expression ``int(o)``.
+
+
+.. cfunction:: PyObject* PyNumber_Long(PyObject *o)
+
+ .. index:: builtin: long
+
+ Returns the *o* converted to a long integer object on success, or *NULL* on
+ failure. This is the equivalent of the Python expression ``long(o)``.
+
+
+.. cfunction:: PyObject* PyNumber_Float(PyObject *o)
+
+ .. index:: builtin: float
+
+ Returns the *o* converted to a float object on success, or *NULL* on failure.
+ This is the equivalent of the Python expression ``float(o)``.
+
+
+.. cfunction:: PyObject* PyNumber_Index(PyObject *o)
+
+ Returns the *o* converted to a Python int or long on success or *NULL* with a
+ TypeError exception raised on failure.
+
+ .. versionadded:: 2.5
+
+
+.. cfunction:: Py_ssize_t PyNumber_AsSsize_t(PyObject *o, PyObject *exc)
+
+ Returns *o* converted to a Py_ssize_t value if *o* can be interpreted as an
+ integer. If *o* can be converted to a Python int or long but the attempt to
+ convert to a Py_ssize_t value would raise an :exc:`OverflowError`, then the
+ *exc* argument is the type of exception that will be raised (usually
+ :exc:`IndexError` or :exc:`OverflowError`). If *exc* is *NULL*, then the
+ exception is cleared and the value is clipped to *PY_SSIZE_T_MIN* for a negative
+ integer or *PY_SSIZE_T_MAX* for a positive integer.
+
+ .. versionadded:: 2.5
+
+
+.. cfunction:: int PyIndex_Check(PyObject *o)
+
+ Returns True if *o* is an index integer (has the nb_index slot of the
+ tp_as_number structure filled in).
+
+ .. versionadded:: 2.5
+
+
+.. _sequence:
+
+Sequence Protocol
+=================
+
+
+.. cfunction:: int PySequence_Check(PyObject *o)
+
+ Return ``1`` if the object provides sequence protocol, and ``0`` otherwise.
+ This function always succeeds.
+
+
+.. cfunction:: Py_ssize_t PySequence_Size(PyObject *o)
+
+ .. index:: builtin: len
+
+ Returns the number of objects in sequence *o* on success, and ``-1`` on failure.
+ For objects that do not provide sequence protocol, this is equivalent to the
+ Python expression ``len(o)``.
+
+
+.. cfunction:: Py_ssize_t PySequence_Length(PyObject *o)
+
+ Alternate name for :cfunc:`PySequence_Size`.
+
+
+.. cfunction:: PyObject* PySequence_Concat(PyObject *o1, PyObject *o2)
+
+ Return the concatenation of *o1* and *o2* on success, and *NULL* on failure.
+ This is the equivalent of the Python expression ``o1 + o2``.
+
+
+.. cfunction:: PyObject* PySequence_Repeat(PyObject *o, Py_ssize_t count)
+
+ Return the result of repeating sequence object *o* *count* times, or *NULL* on
+ failure. This is the equivalent of the Python expression ``o * count``.
+
+
+.. cfunction:: PyObject* PySequence_InPlaceConcat(PyObject *o1, PyObject *o2)
+
+ Return the concatenation of *o1* and *o2* on success, and *NULL* on failure.
+ The operation is done *in-place* when *o1* supports it. This is the equivalent
+ of the Python expression ``o1 += o2``.
+
+
+.. cfunction:: PyObject* PySequence_InPlaceRepeat(PyObject *o, Py_ssize_t count)
+
+ Return the result of repeating sequence object *o* *count* times, or *NULL* on
+ failure. The operation is done *in-place* when *o* supports it. This is the
+ equivalent of the Python expression ``o *= count``.
+
+
+.. cfunction:: PyObject* PySequence_GetItem(PyObject *o, Py_ssize_t i)
+
+ Return the *i*th element of *o*, or *NULL* on failure. This is the equivalent of
+ the Python expression ``o[i]``.
+
+
+.. cfunction:: PyObject* PySequence_GetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2)
+
+ Return the slice of sequence object *o* between *i1* and *i2*, or *NULL* on
+ failure. This is the equivalent of the Python expression ``o[i1:i2]``.
+
+
+.. cfunction:: int PySequence_SetItem(PyObject *o, Py_ssize_t i, PyObject *v)
+
+ Assign object *v* to the *i*th element of *o*. Returns ``-1`` on failure. This
+ is the equivalent of the Python statement ``o[i] = v``. This function *does
+ not* steal a reference to *v*.
+
+
+.. cfunction:: int PySequence_DelItem(PyObject *o, Py_ssize_t i)
+
+ Delete the *i*th element of object *o*. Returns ``-1`` on failure. This is the
+ equivalent of the Python statement ``del o[i]``.
+
+
+.. cfunction:: int PySequence_SetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2, PyObject *v)
+
+ Assign the sequence object *v* to the slice in sequence object *o* from *i1* to
+ *i2*. This is the equivalent of the Python statement ``o[i1:i2] = v``.
+
+
+.. cfunction:: int PySequence_DelSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2)
+
+ Delete the slice in sequence object *o* from *i1* to *i2*. Returns ``-1`` on
+ failure. This is the equivalent of the Python statement ``del o[i1:i2]``.
+
+
+.. cfunction:: Py_ssize_t PySequence_Count(PyObject *o, PyObject *value)
+
+ Return the number of occurrences of *value* in *o*, that is, return the number
+ of keys for which ``o[key] == value``. On failure, return ``-1``. This is
+ equivalent to the Python expression ``o.count(value)``.
+
+
+.. cfunction:: int PySequence_Contains(PyObject *o, PyObject *value)
+
+ Determine if *o* contains *value*. If an item in *o* is equal to *value*,
+ return ``1``, otherwise return ``0``. On error, return ``-1``. This is
+ equivalent to the Python expression ``value in o``.
+
+
+.. cfunction:: Py_ssize_t PySequence_Index(PyObject *o, PyObject *value)
+
+ Return the first index *i* for which ``o[i] == value``. On error, return
+ ``-1``. This is equivalent to the Python expression ``o.index(value)``.
+
+
+.. cfunction:: PyObject* PySequence_List(PyObject *o)
+
+ Return a list object with the same contents as the arbitrary sequence *o*. The
+ returned list is guaranteed to be new.
+
+
+.. cfunction:: PyObject* PySequence_Tuple(PyObject *o)
+
+ .. index:: builtin: tuple
+
+ Return a tuple object with the same contents as the arbitrary sequence *o* or
+ *NULL* on failure. If *o* is a tuple, a new reference will be returned,
+ otherwise a tuple will be constructed with the appropriate contents. This is
+ equivalent to the Python expression ``tuple(o)``.
+
+
+.. cfunction:: PyObject* PySequence_Fast(PyObject *o, const char *m)
+
+ Returns the sequence *o* as a tuple, unless it is already a tuple or list, in
+ which case *o* is returned. Use :cfunc:`PySequence_Fast_GET_ITEM` to access the
+ members of the result. Returns *NULL* on failure. If the object is not a
+ sequence, raises :exc:`TypeError` with *m* as the message text.
+
+
+.. cfunction:: PyObject* PySequence_Fast_GET_ITEM(PyObject *o, Py_ssize_t i)
+
+ Return the *i*th element of *o*, assuming that *o* was returned by
+ :cfunc:`PySequence_Fast`, *o* is not *NULL*, and that *i* is within bounds.
+
+
+.. cfunction:: PyObject** PySequence_Fast_ITEMS(PyObject *o)
+
+ Return the underlying array of PyObject pointers. Assumes that *o* was returned
+ by :cfunc:`PySequence_Fast` and *o* is not *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PySequence_ITEM(PyObject *o, Py_ssize_t i)
+
+ Return the *i*th element of *o* or *NULL* on failure. Macro form of
+ :cfunc:`PySequence_GetItem` but without checking that
+ :cfunc:`PySequence_Check(o)` is true and without adjustment for negative
+ indices.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: Py_ssize_t PySequence_Fast_GET_SIZE(PyObject *o)
+
+ Returns the length of *o*, assuming that *o* was returned by
+ :cfunc:`PySequence_Fast` and that *o* is not *NULL*. The size can also be
+ gotten by calling :cfunc:`PySequence_Size` on *o*, but
+ :cfunc:`PySequence_Fast_GET_SIZE` is faster because it can assume *o* is a list
+ or tuple.
+
+
+.. _mapping:
+
+Mapping Protocol
+================
+
+
+.. cfunction:: int PyMapping_Check(PyObject *o)
+
+ Return ``1`` if the object provides mapping protocol, and ``0`` otherwise. This
+ function always succeeds.
+
+
+.. cfunction:: Py_ssize_t PyMapping_Length(PyObject *o)
+
+ .. index:: builtin: len
+
+ Returns the number of keys in object *o* on success, and ``-1`` on failure. For
+ objects that do not provide mapping protocol, this is equivalent to the Python
+ expression ``len(o)``.
+
+
+.. cfunction:: int PyMapping_DelItemString(PyObject *o, char *key)
+
+ Remove the mapping for object *key* from the object *o*. Return ``-1`` on
+ failure. This is equivalent to the Python statement ``del o[key]``.
+
+
+.. cfunction:: int PyMapping_DelItem(PyObject *o, PyObject *key)
+
+ Remove the mapping for object *key* from the object *o*. Return ``-1`` on
+ failure. This is equivalent to the Python statement ``del o[key]``.
+
+
+.. cfunction:: int PyMapping_HasKeyString(PyObject *o, char *key)
+
+ On success, return ``1`` if the mapping object has the key *key* and ``0``
+ otherwise. This is equivalent to the Python expression ``o.has_key(key)``.
+ This function always succeeds.
+
+
+.. cfunction:: int PyMapping_HasKey(PyObject *o, PyObject *key)
+
+ Return ``1`` if the mapping object has the key *key* and ``0`` otherwise. This
+ is equivalent to the Python expression ``o.has_key(key)``. This function always
+ succeeds.
+
+
+.. cfunction:: PyObject* PyMapping_Keys(PyObject *o)
+
+ On success, return a list of the keys in object *o*. On failure, return *NULL*.
+ This is equivalent to the Python expression ``o.keys()``.
+
+
+.. cfunction:: PyObject* PyMapping_Values(PyObject *o)
+
+ On success, return a list of the values in object *o*. On failure, return
+ *NULL*. This is equivalent to the Python expression ``o.values()``.
+
+
+.. cfunction:: PyObject* PyMapping_Items(PyObject *o)
+
+ On success, return a list of the items in object *o*, where each item is a tuple
+ containing a key-value pair. On failure, return *NULL*. This is equivalent to
+ the Python expression ``o.items()``.
+
+
+.. cfunction:: PyObject* PyMapping_GetItemString(PyObject *o, char *key)
+
+ Return element of *o* corresponding to the object *key* or *NULL* on failure.
+ This is the equivalent of the Python expression ``o[key]``.
+
+
+.. cfunction:: int PyMapping_SetItemString(PyObject *o, char *key, PyObject *v)
+
+ Map the object *key* to the value *v* in object *o*. Returns ``-1`` on failure.
+ This is the equivalent of the Python statement ``o[key] = v``.
+
+
+.. _iterator:
+
+Iterator Protocol
+=================
+
+.. versionadded:: 2.2
+
+There are only a couple of functions specifically for working with iterators.
+
+
+.. cfunction:: int PyIter_Check(PyObject *o)
+
+ Return true if the object *o* supports the iterator protocol.
+
+
+.. cfunction:: PyObject* PyIter_Next(PyObject *o)
+
+ Return the next value from the iteration *o*. If the object is an iterator,
+ this retrieves the next value from the iteration, and returns *NULL* with no
+ exception set if there are no remaining items. If the object is not an
+ iterator, :exc:`TypeError` is raised, or if there is an error in retrieving the
+ item, returns *NULL* and passes along the exception.
+
+To write a loop which iterates over an iterator, the C code should look
+something like this::
+
+ PyObject *iterator = PyObject_GetIter(obj);
+ PyObject *item;
+
+ if (iterator == NULL) {
+ /* propagate error */
+ }
+
+ while (item = PyIter_Next(iterator)) {
+ /* do something with item */
+ ...
+ /* release reference when done */
+ Py_DECREF(item);
+ }
+
+ Py_DECREF(iterator);
+
+ if (PyErr_Occurred()) {
+ /* propagate error */
+ }
+ else {
+ /* continue doing useful work */
+ }
+
+
+.. _abstract-buffer:
+
+Buffer Protocol
+===============
+
+
+.. cfunction:: int PyObject_AsCharBuffer(PyObject *obj, const char **buffer, Py_ssize_t *buffer_len)
+
+ Returns a pointer to a read-only memory location useable as character- based
+ input. The *obj* argument must support the single-segment character buffer
+ interface. On success, returns ``0``, sets *buffer* to the memory location and
+ *buffer_len* to the buffer length. Returns ``-1`` and sets a :exc:`TypeError`
+ on error.
+
+ .. versionadded:: 1.6
+
+
+.. cfunction:: int PyObject_AsReadBuffer(PyObject *obj, const void **buffer, Py_ssize_t *buffer_len)
+
+ Returns a pointer to a read-only memory location containing arbitrary data. The
+ *obj* argument must support the single-segment readable buffer interface. On
+ success, returns ``0``, sets *buffer* to the memory location and *buffer_len* to
+ the buffer length. Returns ``-1`` and sets a :exc:`TypeError` on error.
+
+ .. versionadded:: 1.6
+
+
+.. cfunction:: int PyObject_CheckReadBuffer(PyObject *o)
+
+ Returns ``1`` if *o* supports the single-segment readable buffer interface.
+ Otherwise returns ``0``.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyObject_AsWriteBuffer(PyObject *obj, void **buffer, Py_ssize_t *buffer_len)
+
+ Returns a pointer to a writeable memory location. The *obj* argument must
+ support the single-segment, character buffer interface. On success, returns
+ ``0``, sets *buffer* to the memory location and *buffer_len* to the buffer
+ length. Returns ``-1`` and sets a :exc:`TypeError` on error.
+
+ .. versionadded:: 1.6
+
diff --git a/Doc/c-api/concrete.rst b/Doc/c-api/concrete.rst
new file mode 100644
index 0000000000..052785c0ac
--- /dev/null
+++ b/Doc/c-api/concrete.rst
@@ -0,0 +1,3676 @@
+.. highlightlang:: c
+
+
+.. _concrete:
+
+**********************
+Concrete Objects Layer
+**********************
+
+The functions in this chapter are specific to certain Python object types.
+Passing them an object of the wrong type is not a good idea; if you receive an
+object from a Python program and you are not sure that it has the right type,
+you must perform a type check first; for example, to check that an object is a
+dictionary, use :cfunc:`PyDict_Check`. The chapter is structured like the
+"family tree" of Python object types.
+
+.. warning::
+
+ While the functions described in this chapter carefully check the type of the
+ objects which are passed in, many of them do not check for *NULL* being passed
+ instead of a valid object. Allowing *NULL* to be passed in can cause memory
+ access violations and immediate termination of the interpreter.
+
+
+.. _fundamental:
+
+Fundamental Objects
+===================
+
+This section describes Python type objects and the singleton object ``None``.
+
+
+.. _typeobjects:
+
+Type Objects
+------------
+
+.. index:: object: type
+
+
+.. ctype:: PyTypeObject
+
+ The C structure of the objects used to describe built-in types.
+
+
+.. cvar:: PyObject* PyType_Type
+
+ .. index:: single: TypeType (in module types)
+
+ This is the type object for type objects; it is the same object as ``type`` and
+ ``types.TypeType`` in the Python layer.
+
+
+.. cfunction:: int PyType_Check(PyObject *o)
+
+ Return true if the object *o* is a type object, including instances of types
+ derived from the standard type object. Return false in all other cases.
+
+
+.. cfunction:: int PyType_CheckExact(PyObject *o)
+
+ Return true if the object *o* is a type object, but not a subtype of the
+ standard type object. Return false in all other cases.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyType_HasFeature(PyObject *o, int feature)
+
+ Return true if the type object *o* sets the feature *feature*. Type features
+ are denoted by single bit flags.
+
+
+.. cfunction:: int PyType_IS_GC(PyObject *o)
+
+ Return true if the type object includes support for the cycle detector; this
+ tests the type flag :const:`Py_TPFLAGS_HAVE_GC`.
+
+ .. versionadded:: 2.0
+
+
+.. cfunction:: int PyType_IsSubtype(PyTypeObject *a, PyTypeObject *b)
+
+ Return true if *a* is a subtype of *b*.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyType_GenericAlloc(PyTypeObject *type, Py_ssize_t nitems)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyType_GenericNew(PyTypeObject *type, PyObject *args, PyObject *kwds)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyType_Ready(PyTypeObject *type)
+
+ Finalize a type object. This should be called on all type objects to finish
+ their initialization. This function is responsible for adding inherited slots
+ from a type's base class. Return ``0`` on success, or return ``-1`` and sets an
+ exception on error.
+
+ .. versionadded:: 2.2
+
+
+.. _noneobject:
+
+The None Object
+---------------
+
+.. index:: object: None
+
+Note that the :ctype:`PyTypeObject` for ``None`` is not directly exposed in the
+Python/C API. Since ``None`` is a singleton, testing for object identity (using
+``==`` in C) is sufficient. There is no :cfunc:`PyNone_Check` function for the
+same reason.
+
+
+.. cvar:: PyObject* Py_None
+
+ The Python ``None`` object, denoting lack of value. This object has no methods.
+ It needs to be treated just like any other object with respect to reference
+ counts.
+
+
+.. cmacro:: Py_RETURN_NONE
+
+ Properly handle returning :cdata:`Py_None` from within a C function.
+
+ .. versionadded:: 2.4
+
+
+.. _numericobjects:
+
+Numeric Objects
+===============
+
+.. index:: object: numeric
+
+
+.. _intobjects:
+
+Plain Integer Objects
+---------------------
+
+.. index:: object: integer
+
+
+.. ctype:: PyIntObject
+
+ This subtype of :ctype:`PyObject` represents a Python integer object.
+
+
+.. cvar:: PyTypeObject PyInt_Type
+
+ .. index:: single: IntType (in modules types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python plain integer type.
+ This is the same object as ``int`` and ``types.IntType``.
+
+
+.. cfunction:: int PyInt_Check(PyObject *o)
+
+ Return true if *o* is of type :cdata:`PyInt_Type` or a subtype of
+ :cdata:`PyInt_Type`.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyInt_CheckExact(PyObject *o)
+
+ Return true if *o* is of type :cdata:`PyInt_Type`, but not a subtype of
+ :cdata:`PyInt_Type`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyInt_FromString(char *str, char **pend, int base)
+
+ Return a new :ctype:`PyIntObject` or :ctype:`PyLongObject` based on the string
+ value in *str*, which is interpreted according to the radix in *base*. If
+ *pend* is non-*NULL*, ``*pend`` will point to the first character in *str* which
+ follows the representation of the number. If *base* is ``0``, the radix will be
+ determined based on the leading characters of *str*: if *str* starts with
+ ``'0x'`` or ``'0X'``, radix 16 will be used; if *str* starts with ``'0'``, radix
+ 8 will be used; otherwise radix 10 will be used. If *base* is not ``0``, it
+ must be between ``2`` and ``36``, inclusive. Leading spaces are ignored. If
+ there are no digits, :exc:`ValueError` will be raised. If the string represents
+ a number too large to be contained within the machine's :ctype:`long int` type
+ and overflow warnings are being suppressed, a :ctype:`PyLongObject` will be
+ returned. If overflow warnings are not being suppressed, *NULL* will be
+ returned in this case.
+
+
+.. cfunction:: PyObject* PyInt_FromLong(long ival)
+
+ Create a new integer object with a value of *ival*.
+
+ The current implementation keeps an array of integer objects for all integers
+ between ``-5`` and ``256``, when you create an int in that range you actually
+ just get back a reference to the existing object. So it should be possible to
+ change the value of ``1``. I suspect the behaviour of Python in this case is
+ undefined. :-)
+
+
+.. cfunction:: PyObject* PyInt_FromSsize_t(Py_ssize_t ival)
+
+ Create a new integer object with a value of *ival*. If the value exceeds
+ ``LONG_MAX``, a long integer object is returned.
+
+ .. versionadded:: 2.5
+
+
+.. cfunction:: long PyInt_AsLong(PyObject *io)
+
+ Will first attempt to cast the object to a :ctype:`PyIntObject`, if it is not
+ already one, and then return its value. If there is an error, ``-1`` is
+ returned, and the caller should check ``PyErr_Occurred()`` to find out whether
+ there was an error, or whether the value just happened to be -1.
+
+
+.. cfunction:: long PyInt_AS_LONG(PyObject *io)
+
+ Return the value of the object *io*. No error checking is performed.
+
+
+.. cfunction:: unsigned long PyInt_AsUnsignedLongMask(PyObject *io)
+
+ Will first attempt to cast the object to a :ctype:`PyIntObject` or
+ :ctype:`PyLongObject`, if it is not already one, and then return its value as
+ unsigned long. This function does not check for overflow.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: unsigned PY_LONG_LONG PyInt_AsUnsignedLongLongMask(PyObject *io)
+
+ Will first attempt to cast the object to a :ctype:`PyIntObject` or
+ :ctype:`PyLongObject`, if it is not already one, and then return its value as
+ unsigned long long, without checking for overflow.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: Py_ssize_t PyInt_AsSsize_t(PyObject *io)
+
+ Will first attempt to cast the object to a :ctype:`PyIntObject` or
+ :ctype:`PyLongObject`, if it is not already one, and then return its value as
+ :ctype:`Py_ssize_t`.
+
+ .. versionadded:: 2.5
+
+
+.. cfunction:: long PyInt_GetMax()
+
+ .. index:: single: LONG_MAX
+
+ Return the system's idea of the largest integer it can handle
+ (:const:`LONG_MAX`, as defined in the system header files).
+
+
+.. _boolobjects:
+
+Boolean Objects
+---------------
+
+Booleans in Python are implemented as a subclass of integers. There are only
+two booleans, :const:`Py_False` and :const:`Py_True`. As such, the normal
+creation and deletion functions don't apply to booleans. The following macros
+are available, however.
+
+
+.. cfunction:: int PyBool_Check(PyObject *o)
+
+ Return true if *o* is of type :cdata:`PyBool_Type`.
+
+ .. versionadded:: 2.3
+
+
+.. cvar:: PyObject* Py_False
+
+ The Python ``False`` object. This object has no methods. It needs to be
+ treated just like any other object with respect to reference counts.
+
+
+.. cvar:: PyObject* Py_True
+
+ The Python ``True`` object. This object has no methods. It needs to be treated
+ just like any other object with respect to reference counts.
+
+
+.. cmacro:: Py_RETURN_FALSE
+
+ Return :const:`Py_False` from a function, properly incrementing its reference
+ count.
+
+ .. versionadded:: 2.4
+
+
+.. cmacro:: Py_RETURN_TRUE
+
+ Return :const:`Py_True` from a function, properly incrementing its reference
+ count.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyBool_FromLong(long v)
+
+ Return a new reference to :const:`Py_True` or :const:`Py_False` depending on the
+ truth value of *v*.
+
+ .. versionadded:: 2.3
+
+
+.. _longobjects:
+
+Long Integer Objects
+--------------------
+
+.. index:: object: long integer
+
+
+.. ctype:: PyLongObject
+
+ This subtype of :ctype:`PyObject` represents a Python long integer object.
+
+
+.. cvar:: PyTypeObject PyLong_Type
+
+ .. index:: single: LongType (in modules types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python long integer type.
+ This is the same object as ``long`` and ``types.LongType``.
+
+
+.. cfunction:: int PyLong_Check(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyLongObject` or a subtype of
+ :ctype:`PyLongObject`.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyLong_CheckExact(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyLongObject`, but not a subtype of
+ :ctype:`PyLongObject`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyLong_FromLong(long v)
+
+ Return a new :ctype:`PyLongObject` object from *v*, or *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyLong_FromUnsignedLong(unsigned long v)
+
+ Return a new :ctype:`PyLongObject` object from a C :ctype:`unsigned long`, or
+ *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyLong_FromLongLong(PY_LONG_LONG v)
+
+ Return a new :ctype:`PyLongObject` object from a C :ctype:`long long`, or *NULL*
+ on failure.
+
+
+.. cfunction:: PyObject* PyLong_FromUnsignedLongLong(unsigned PY_LONG_LONG v)
+
+ Return a new :ctype:`PyLongObject` object from a C :ctype:`unsigned long long`,
+ or *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyLong_FromDouble(double v)
+
+ Return a new :ctype:`PyLongObject` object from the integer part of *v*, or
+ *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyLong_FromString(char *str, char **pend, int base)
+
+ Return a new :ctype:`PyLongObject` based on the string value in *str*, which is
+ interpreted according to the radix in *base*. If *pend* is non-*NULL*,
+ ``*pend`` will point to the first character in *str* which follows the
+ representation of the number. If *base* is ``0``, the radix will be determined
+ based on the leading characters of *str*: if *str* starts with ``'0x'`` or
+ ``'0X'``, radix 16 will be used; if *str* starts with ``'0'``, radix 8 will be
+ used; otherwise radix 10 will be used. If *base* is not ``0``, it must be
+ between ``2`` and ``36``, inclusive. Leading spaces are ignored. If there are
+ no digits, :exc:`ValueError` will be raised.
+
+
+.. cfunction:: PyObject* PyLong_FromUnicode(Py_UNICODE *u, Py_ssize_t length, int base)
+
+ Convert a sequence of Unicode digits to a Python long integer value. The first
+ parameter, *u*, points to the first character of the Unicode string, *length*
+ gives the number of characters, and *base* is the radix for the conversion. The
+ radix must be in the range [2, 36]; if it is out of range, :exc:`ValueError`
+ will be raised.
+
+ .. versionadded:: 1.6
+
+
+.. cfunction:: PyObject* PyLong_FromVoidPtr(void *p)
+
+ Create a Python integer or long integer from the pointer *p*. The pointer value
+ can be retrieved from the resulting value using :cfunc:`PyLong_AsVoidPtr`.
+
+ .. versionadded:: 1.5.2
+
+ .. versionchanged:: 2.5
+ If the integer is larger than LONG_MAX, a positive long integer is returned.
+
+
+.. cfunction:: long PyLong_AsLong(PyObject *pylong)
+
+ .. index::
+ single: LONG_MAX
+ single: OverflowError (built-in exception)
+
+ Return a C :ctype:`long` representation of the contents of *pylong*. If
+ *pylong* is greater than :const:`LONG_MAX`, an :exc:`OverflowError` is raised.
+
+
+.. cfunction:: unsigned long PyLong_AsUnsignedLong(PyObject *pylong)
+
+ .. index::
+ single: ULONG_MAX
+ single: OverflowError (built-in exception)
+
+ Return a C :ctype:`unsigned long` representation of the contents of *pylong*.
+ If *pylong* is greater than :const:`ULONG_MAX`, an :exc:`OverflowError` is
+ raised.
+
+
+.. cfunction:: PY_LONG_LONG PyLong_AsLongLong(PyObject *pylong)
+
+ Return a C :ctype:`long long` from a Python long integer. If *pylong* cannot be
+ represented as a :ctype:`long long`, an :exc:`OverflowError` will be raised.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: unsigned PY_LONG_LONG PyLong_AsUnsignedLongLong(PyObject *pylong)
+
+ Return a C :ctype:`unsigned long long` from a Python long integer. If *pylong*
+ cannot be represented as an :ctype:`unsigned long long`, an :exc:`OverflowError`
+ will be raised if the value is positive, or a :exc:`TypeError` will be raised if
+ the value is negative.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: unsigned long PyLong_AsUnsignedLongMask(PyObject *io)
+
+ Return a C :ctype:`unsigned long` from a Python long integer, without checking
+ for overflow.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: unsigned PY_LONG_LONG PyLong_AsUnsignedLongLongMask(PyObject *io)
+
+ Return a C :ctype:`unsigned long long` from a Python long integer, without
+ checking for overflow.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: double PyLong_AsDouble(PyObject *pylong)
+
+ Return a C :ctype:`double` representation of the contents of *pylong*. If
+ *pylong* cannot be approximately represented as a :ctype:`double`, an
+ :exc:`OverflowError` exception is raised and ``-1.0`` will be returned.
+
+
+.. cfunction:: void* PyLong_AsVoidPtr(PyObject *pylong)
+
+ Convert a Python integer or long integer *pylong* to a C :ctype:`void` pointer.
+ If *pylong* cannot be converted, an :exc:`OverflowError` will be raised. This
+ is only assured to produce a usable :ctype:`void` pointer for values created
+ with :cfunc:`PyLong_FromVoidPtr`.
+
+ .. versionadded:: 1.5.2
+
+ .. versionchanged:: 2.5
+ For values outside 0..LONG_MAX, both signed and unsigned integers are acccepted.
+
+
+.. _floatobjects:
+
+Floating Point Objects
+----------------------
+
+.. index:: object: floating point
+
+
+.. ctype:: PyFloatObject
+
+ This subtype of :ctype:`PyObject` represents a Python floating point object.
+
+
+.. cvar:: PyTypeObject PyFloat_Type
+
+ .. index:: single: FloatType (in modules types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python floating point
+ type. This is the same object as ``float`` and ``types.FloatType``.
+
+
+.. cfunction:: int PyFloat_Check(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyFloatObject` or a subtype of
+ :ctype:`PyFloatObject`.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyFloat_CheckExact(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyFloatObject`, but not a subtype of
+ :ctype:`PyFloatObject`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyFloat_FromString(PyObject *str)
+
+ Create a :ctype:`PyFloatObject` object based on the string value in *str*, or
+ *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyFloat_FromDouble(double v)
+
+ Create a :ctype:`PyFloatObject` object from *v*, or *NULL* on failure.
+
+
+.. cfunction:: double PyFloat_AsDouble(PyObject *pyfloat)
+
+ Return a C :ctype:`double` representation of the contents of *pyfloat*. If
+ *pyfloat* is not a Python floating point object but has a :meth:`__float__`
+ method, this method will first be called to convert *pyfloat* into a float.
+
+
+.. cfunction:: double PyFloat_AS_DOUBLE(PyObject *pyfloat)
+
+ Return a C :ctype:`double` representation of the contents of *pyfloat*, but
+ without error checking.
+
+
+.. _complexobjects:
+
+Complex Number Objects
+----------------------
+
+.. index:: object: complex number
+
+Python's complex number objects are implemented as two distinct types when
+viewed from the C API: one is the Python object exposed to Python programs, and
+the other is a C structure which represents the actual complex number value.
+The API provides functions for working with both.
+
+
+Complex Numbers as C Structures
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Note that the functions which accept these structures as parameters and return
+them as results do so *by value* rather than dereferencing them through
+pointers. This is consistent throughout the API.
+
+
+.. ctype:: Py_complex
+
+ The C structure which corresponds to the value portion of a Python complex
+ number object. Most of the functions for dealing with complex number objects
+ use structures of this type as input or output values, as appropriate. It is
+ defined as::
+
+ typedef struct {
+ double real;
+ double imag;
+ } Py_complex;
+
+
+.. cfunction:: Py_complex _Py_c_sum(Py_complex left, Py_complex right)
+
+ Return the sum of two complex numbers, using the C :ctype:`Py_complex`
+ representation.
+
+
+.. cfunction:: Py_complex _Py_c_diff(Py_complex left, Py_complex right)
+
+ Return the difference between two complex numbers, using the C
+ :ctype:`Py_complex` representation.
+
+
+.. cfunction:: Py_complex _Py_c_neg(Py_complex complex)
+
+ Return the negation of the complex number *complex*, using the C
+ :ctype:`Py_complex` representation.
+
+
+.. cfunction:: Py_complex _Py_c_prod(Py_complex left, Py_complex right)
+
+ Return the product of two complex numbers, using the C :ctype:`Py_complex`
+ representation.
+
+
+.. cfunction:: Py_complex _Py_c_quot(Py_complex dividend, Py_complex divisor)
+
+ Return the quotient of two complex numbers, using the C :ctype:`Py_complex`
+ representation.
+
+
+.. cfunction:: Py_complex _Py_c_pow(Py_complex num, Py_complex exp)
+
+ Return the exponentiation of *num* by *exp*, using the C :ctype:`Py_complex`
+ representation.
+
+
+Complex Numbers as Python Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+
+.. ctype:: PyComplexObject
+
+ This subtype of :ctype:`PyObject` represents a Python complex number object.
+
+
+.. cvar:: PyTypeObject PyComplex_Type
+
+ This instance of :ctype:`PyTypeObject` represents the Python complex number
+ type. It is the same object as ``complex`` and ``types.ComplexType``.
+
+
+.. cfunction:: int PyComplex_Check(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyComplexObject` or a subtype of
+ :ctype:`PyComplexObject`.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyComplex_CheckExact(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyComplexObject`, but not a subtype of
+ :ctype:`PyComplexObject`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyComplex_FromCComplex(Py_complex v)
+
+ Create a new Python complex number object from a C :ctype:`Py_complex` value.
+
+
+.. cfunction:: PyObject* PyComplex_FromDoubles(double real, double imag)
+
+ Return a new :ctype:`PyComplexObject` object from *real* and *imag*.
+
+
+.. cfunction:: double PyComplex_RealAsDouble(PyObject *op)
+
+ Return the real part of *op* as a C :ctype:`double`.
+
+
+.. cfunction:: double PyComplex_ImagAsDouble(PyObject *op)
+
+ Return the imaginary part of *op* as a C :ctype:`double`.
+
+
+.. cfunction:: Py_complex PyComplex_AsCComplex(PyObject *op)
+
+ Return the :ctype:`Py_complex` value of the complex number *op*.
+
+ .. versionchanged:: 2.6
+ If *op* is not a Python complex number object but has a :meth:`__complex__`
+ method, this method will first be called to convert *op* to a Python complex
+ number object.
+
+
+.. _sequenceobjects:
+
+Sequence Objects
+================
+
+.. index:: object: sequence
+
+Generic operations on sequence objects were discussed in the previous chapter;
+this section deals with the specific kinds of sequence objects that are
+intrinsic to the Python language.
+
+
+.. _stringobjects:
+
+String Objects
+--------------
+
+These functions raise :exc:`TypeError` when expecting a string parameter and are
+called with a non-string parameter.
+
+.. index:: object: string
+
+
+.. ctype:: PyStringObject
+
+ This subtype of :ctype:`PyObject` represents a Python string object.
+
+
+.. cvar:: PyTypeObject PyString_Type
+
+ .. index:: single: StringType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python string type; it is
+ the same object as ``str`` and ``types.StringType`` in the Python layer. .
+
+
+.. cfunction:: int PyString_Check(PyObject *o)
+
+ Return true if the object *o* is a string object or an instance of a subtype of
+ the string type.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyString_CheckExact(PyObject *o)
+
+ Return true if the object *o* is a string object, but not an instance of a
+ subtype of the string type.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyString_FromString(const char *v)
+
+ Return a new string object with a copy of the string *v* as value on success,
+ and *NULL* on failure. The parameter *v* must not be *NULL*; it will not be
+ checked.
+
+
+.. cfunction:: PyObject* PyString_FromStringAndSize(const char *v, Py_ssize_t len)
+
+ Return a new string object with a copy of the string *v* as value and length
+ *len* on success, and *NULL* on failure. If *v* is *NULL*, the contents of the
+ string are uninitialized.
+
+
+.. cfunction:: PyObject* PyString_FromFormat(const char *format, ...)
+
+ Take a C :cfunc:`printf`\ -style *format* string and a variable number of
+ arguments, calculate the size of the resulting Python string and return a string
+ with the values formatted into it. The variable arguments must be C types and
+ must correspond exactly to the format characters in the *format* string. The
+ following format characters are allowed:
+
+ .. % This should be exactly the same as the table in PyErr_Format.
+ .. % One should just refer to the other.
+ .. % The descriptions for %zd and %zu are wrong, but the truth is complicated
+ .. % because not all compilers support the %z width modifier -- we fake it
+ .. % when necessary via interpolating PY_FORMAT_SIZE_T.
+ .. % %u, %lu, %zu should have "new in Python 2.5" blurbs.
+
+ +-------------------+---------------+--------------------------------+
+ | Format Characters | Type | Comment |
+ +===================+===============+================================+
+ | :attr:`%%` | *n/a* | The literal % character. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%c` | int | A single character, |
+ | | | represented as an C int. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%d` | int | Exactly equivalent to |
+ | | | ``printf("%d")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%u` | unsigned int | Exactly equivalent to |
+ | | | ``printf("%u")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%ld` | long | Exactly equivalent to |
+ | | | ``printf("%ld")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%lu` | unsigned long | Exactly equivalent to |
+ | | | ``printf("%lu")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%zd` | Py_ssize_t | Exactly equivalent to |
+ | | | ``printf("%zd")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%zu` | size_t | Exactly equivalent to |
+ | | | ``printf("%zu")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%i` | int | Exactly equivalent to |
+ | | | ``printf("%i")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%x` | int | Exactly equivalent to |
+ | | | ``printf("%x")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%s` | char\* | A null-terminated C character |
+ | | | array. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%p` | void\* | The hex representation of a C |
+ | | | pointer. Mostly equivalent to |
+ | | | ``printf("%p")`` except that |
+ | | | it is guaranteed to start with |
+ | | | the literal ``0x`` regardless |
+ | | | of what the platform's |
+ | | | ``printf`` yields. |
+ +-------------------+---------------+--------------------------------+
+
+ An unrecognized format character causes all the rest of the format string to be
+ copied as-is to the result string, and any extra arguments discarded.
+
+
+.. cfunction:: PyObject* PyString_FromFormatV(const char *format, va_list vargs)
+
+ Identical to :func:`PyString_FromFormat` except that it takes exactly two
+ arguments.
+
+
+.. cfunction:: Py_ssize_t PyString_Size(PyObject *string)
+
+ Return the length of the string in string object *string*.
+
+
+.. cfunction:: Py_ssize_t PyString_GET_SIZE(PyObject *string)
+
+ Macro form of :cfunc:`PyString_Size` but without error checking.
+
+
+.. cfunction:: char* PyString_AsString(PyObject *string)
+
+ Return a NUL-terminated representation of the contents of *string*. The pointer
+ refers to the internal buffer of *string*, not a copy. The data must not be
+ modified in any way, unless the string was just created using
+ ``PyString_FromStringAndSize(NULL, size)``. It must not be deallocated. If
+ *string* is a Unicode object, this function computes the default encoding of
+ *string* and operates on that. If *string* is not a string object at all,
+ :cfunc:`PyString_AsString` returns *NULL* and raises :exc:`TypeError`.
+
+
+.. cfunction:: char* PyString_AS_STRING(PyObject *string)
+
+ Macro form of :cfunc:`PyString_AsString` but without error checking. Only
+ string objects are supported; no Unicode objects should be passed.
+
+
+.. cfunction:: int PyString_AsStringAndSize(PyObject *obj, char **buffer, Py_ssize_t *length)
+
+ Return a NUL-terminated representation of the contents of the object *obj*
+ through the output variables *buffer* and *length*.
+
+ The function accepts both string and Unicode objects as input. For Unicode
+ objects it returns the default encoded version of the object. If *length* is
+ *NULL*, the resulting buffer may not contain NUL characters; if it does, the
+ function returns ``-1`` and a :exc:`TypeError` is raised.
+
+ The buffer refers to an internal string buffer of *obj*, not a copy. The data
+ must not be modified in any way, unless the string was just created using
+ ``PyString_FromStringAndSize(NULL, size)``. It must not be deallocated. If
+ *string* is a Unicode object, this function computes the default encoding of
+ *string* and operates on that. If *string* is not a string object at all,
+ :cfunc:`PyString_AsStringAndSize` returns ``-1`` and raises :exc:`TypeError`.
+
+
+.. cfunction:: void PyString_Concat(PyObject **string, PyObject *newpart)
+
+ Create a new string object in *\*string* containing the contents of *newpart*
+ appended to *string*; the caller will own the new reference. The reference to
+ the old value of *string* will be stolen. If the new string cannot be created,
+ the old reference to *string* will still be discarded and the value of
+ *\*string* will be set to *NULL*; the appropriate exception will be set.
+
+
+.. cfunction:: void PyString_ConcatAndDel(PyObject **string, PyObject *newpart)
+
+ Create a new string object in *\*string* containing the contents of *newpart*
+ appended to *string*. This version decrements the reference count of *newpart*.
+
+
+.. cfunction:: int _PyString_Resize(PyObject **string, Py_ssize_t newsize)
+
+ A way to resize a string object even though it is "immutable". Only use this to
+ build up a brand new string object; don't use this if the string may already be
+ known in other parts of the code. It is an error to call this function if the
+ refcount on the input string object is not one. Pass the address of an existing
+ string object as an lvalue (it may be written into), and the new size desired.
+ On success, *\*string* holds the resized string object and ``0`` is returned;
+ the address in *\*string* may differ from its input value. If the reallocation
+ fails, the original string object at *\*string* is deallocated, *\*string* is
+ set to *NULL*, a memory exception is set, and ``-1`` is returned.
+
+
+.. cfunction:: PyObject* PyString_Format(PyObject *format, PyObject *args)
+
+ Return a new string object from *format* and *args*. Analogous to ``format %
+ args``. The *args* argument must be a tuple.
+
+
+.. cfunction:: void PyString_InternInPlace(PyObject **string)
+
+ Intern the argument *\*string* in place. The argument must be the address of a
+ pointer variable pointing to a Python string object. If there is an existing
+ interned string that is the same as *\*string*, it sets *\*string* to it
+ (decrementing the reference count of the old string object and incrementing the
+ reference count of the interned string object), otherwise it leaves *\*string*
+ alone and interns it (incrementing its reference count). (Clarification: even
+ though there is a lot of talk about reference counts, think of this function as
+ reference-count-neutral; you own the object after the call if and only if you
+ owned it before the call.)
+
+
+.. cfunction:: PyObject* PyString_InternFromString(const char *v)
+
+ A combination of :cfunc:`PyString_FromString` and
+ :cfunc:`PyString_InternInPlace`, returning either a new string object that has
+ been interned, or a new ("owned") reference to an earlier interned string object
+ with the same value.
+
+
+.. cfunction:: PyObject* PyString_Decode(const char *s, Py_ssize_t size, const char *encoding, const char *errors)
+
+ Create an object by decoding *size* bytes of the encoded buffer *s* using the
+ codec registered for *encoding*. *encoding* and *errors* have the same meaning
+ as the parameters of the same name in the :func:`unicode` built-in function.
+ The codec to be used is looked up using the Python codec registry. Return
+ *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyString_AsDecodedObject(PyObject *str, const char *encoding, const char *errors)
+
+ Decode a string object by passing it to the codec registered for *encoding* and
+ return the result as Python object. *encoding* and *errors* have the same
+ meaning as the parameters of the same name in the string :meth:`encode` method.
+ The codec to be used is looked up using the Python codec registry. Return *NULL*
+ if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyString_Encode(const char *s, Py_ssize_t size, const char *encoding, const char *errors)
+
+ Encode the :ctype:`char` buffer of the given size by passing it to the codec
+ registered for *encoding* and return a Python object. *encoding* and *errors*
+ have the same meaning as the parameters of the same name in the string
+ :meth:`encode` method. The codec to be used is looked up using the Python codec
+ registry. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyString_AsEncodedObject(PyObject *str, const char *encoding, const char *errors)
+
+ Encode a string object using the codec registered for *encoding* and return the
+ result as Python object. *encoding* and *errors* have the same meaning as the
+ parameters of the same name in the string :meth:`encode` method. The codec to be
+ used is looked up using the Python codec registry. Return *NULL* if an exception
+ was raised by the codec.
+
+
+.. _unicodeobjects:
+
+Unicode Objects
+---------------
+
+.. sectionauthor:: Marc-Andre Lemburg <mal@lemburg.com>
+
+
+These are the basic Unicode object types used for the Unicode implementation in
+Python:
+
+.. % --- Unicode Type -------------------------------------------------------
+
+
+.. ctype:: Py_UNICODE
+
+ This type represents the storage type which is used by Python internally as
+ basis for holding Unicode ordinals. Python's default builds use a 16-bit type
+ for :ctype:`Py_UNICODE` and store Unicode values internally as UCS2. It is also
+ possible to build a UCS4 version of Python (most recent Linux distributions come
+ with UCS4 builds of Python). These builds then use a 32-bit type for
+ :ctype:`Py_UNICODE` and store Unicode data internally as UCS4. On platforms
+ where :ctype:`wchar_t` is available and compatible with the chosen Python
+ Unicode build variant, :ctype:`Py_UNICODE` is a typedef alias for
+ :ctype:`wchar_t` to enhance native platform compatibility. On all other
+ platforms, :ctype:`Py_UNICODE` is a typedef alias for either :ctype:`unsigned
+ short` (UCS2) or :ctype:`unsigned long` (UCS4).
+
+Note that UCS2 and UCS4 Python builds are not binary compatible. Please keep
+this in mind when writing extensions or interfaces.
+
+
+.. ctype:: PyUnicodeObject
+
+ This subtype of :ctype:`PyObject` represents a Python Unicode object.
+
+
+.. cvar:: PyTypeObject PyUnicode_Type
+
+ This instance of :ctype:`PyTypeObject` represents the Python Unicode type. It
+ is exposed to Python code as ``unicode`` and ``types.UnicodeType``.
+
+The following APIs are really C macros and can be used to do fast checks and to
+access internal read-only data of Unicode objects:
+
+
+.. cfunction:: int PyUnicode_Check(PyObject *o)
+
+ Return true if the object *o* is a Unicode object or an instance of a Unicode
+ subtype.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyUnicode_CheckExact(PyObject *o)
+
+ Return true if the object *o* is a Unicode object, but not an instance of a
+ subtype.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: Py_ssize_t PyUnicode_GET_SIZE(PyObject *o)
+
+ Return the size of the object. *o* has to be a :ctype:`PyUnicodeObject` (not
+ checked).
+
+
+.. cfunction:: Py_ssize_t PyUnicode_GET_DATA_SIZE(PyObject *o)
+
+ Return the size of the object's internal buffer in bytes. *o* has to be a
+ :ctype:`PyUnicodeObject` (not checked).
+
+
+.. cfunction:: Py_UNICODE* PyUnicode_AS_UNICODE(PyObject *o)
+
+ Return a pointer to the internal :ctype:`Py_UNICODE` buffer of the object. *o*
+ has to be a :ctype:`PyUnicodeObject` (not checked).
+
+
+.. cfunction:: const char* PyUnicode_AS_DATA(PyObject *o)
+
+ Return a pointer to the internal buffer of the object. *o* has to be a
+ :ctype:`PyUnicodeObject` (not checked).
+
+Unicode provides many different character properties. The most often needed ones
+are available through these macros which are mapped to C functions depending on
+the Python configuration.
+
+.. % --- Unicode character properties ---------------------------------------
+
+
+.. cfunction:: int Py_UNICODE_ISSPACE(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a whitespace character.
+
+
+.. cfunction:: int Py_UNICODE_ISLOWER(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a lowercase character.
+
+
+.. cfunction:: int Py_UNICODE_ISUPPER(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is an uppercase character.
+
+
+.. cfunction:: int Py_UNICODE_ISTITLE(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a titlecase character.
+
+
+.. cfunction:: int Py_UNICODE_ISLINEBREAK(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a linebreak character.
+
+
+.. cfunction:: int Py_UNICODE_ISDECIMAL(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a decimal character.
+
+
+.. cfunction:: int Py_UNICODE_ISDIGIT(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a digit character.
+
+
+.. cfunction:: int Py_UNICODE_ISNUMERIC(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is a numeric character.
+
+
+.. cfunction:: int Py_UNICODE_ISALPHA(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is an alphabetic character.
+
+
+.. cfunction:: int Py_UNICODE_ISALNUM(Py_UNICODE ch)
+
+ Return 1 or 0 depending on whether *ch* is an alphanumeric character.
+
+These APIs can be used for fast direct character conversions:
+
+
+.. cfunction:: Py_UNICODE Py_UNICODE_TOLOWER(Py_UNICODE ch)
+
+ Return the character *ch* converted to lower case.
+
+
+.. cfunction:: Py_UNICODE Py_UNICODE_TOUPPER(Py_UNICODE ch)
+
+ Return the character *ch* converted to upper case.
+
+
+.. cfunction:: Py_UNICODE Py_UNICODE_TOTITLE(Py_UNICODE ch)
+
+ Return the character *ch* converted to title case.
+
+
+.. cfunction:: int Py_UNICODE_TODECIMAL(Py_UNICODE ch)
+
+ Return the character *ch* converted to a decimal positive integer. Return
+ ``-1`` if this is not possible. This macro does not raise exceptions.
+
+
+.. cfunction:: int Py_UNICODE_TODIGIT(Py_UNICODE ch)
+
+ Return the character *ch* converted to a single digit integer. Return ``-1`` if
+ this is not possible. This macro does not raise exceptions.
+
+
+.. cfunction:: double Py_UNICODE_TONUMERIC(Py_UNICODE ch)
+
+ Return the character *ch* converted to a double. Return ``-1.0`` if this is not
+ possible. This macro does not raise exceptions.
+
+To create Unicode objects and access their basic sequence properties, use these
+APIs:
+
+.. % --- Plain Py_UNICODE ---------------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_FromUnicode(const Py_UNICODE *u, Py_ssize_t size)
+
+ Create a Unicode Object from the Py_UNICODE buffer *u* of the given size. *u*
+ may be *NULL* which causes the contents to be undefined. It is the user's
+ responsibility to fill in the needed data. The buffer is copied into the new
+ object. If the buffer is not *NULL*, the return value might be a shared object.
+ Therefore, modification of the resulting Unicode object is only allowed when *u*
+ is *NULL*.
+
+
+.. cfunction:: PyObject* PyUnicode_FromStringAndSize(const char *u, Py_ssize_t size)
+
+ Create a Unicode Object from the char buffer *u*. The bytes will be interpreted
+ as being UTF-8 encoded. *u* may also be *NULL* which
+ causes the contents to be undefined. It is the user's responsibility to fill in
+ the needed data. The buffer is copied into the new object. If the buffer is not
+ *NULL*, the return value might be a shared object. Therefore, modification of
+ the resulting Unicode object is only allowed when *u* is *NULL*.
+
+ .. versionadded:: 3.0
+
+
+.. cfunction:: PyObject *PyUnicode_FromString(const char *u)
+
+ Create a Unicode object from an UTF-8 encoded null-terminated char buffer
+ *u*.
+
+ .. versionadded:: 3.0
+
+
+.. cfunction:: PyObject* PyUnicode_FromFormat(const char *format, ...)
+
+ Take a C :cfunc:`printf`\ -style *format* string and a variable number of
+ arguments, calculate the size of the resulting Python unicode string and return
+ a string with the values formatted into it. The variable arguments must be C
+ types and must correspond exactly to the format characters in the *format*
+ string. The following format characters are allowed:
+
+ .. % The descriptions for %zd and %zu are wrong, but the truth is complicated
+ .. % because not all compilers support the %z width modifier -- we fake it
+ .. % when necessary via interpolating PY_FORMAT_SIZE_T.
+
+ +-------------------+---------------------+--------------------------------+
+ | Format Characters | Type | Comment |
+ +===================+=====================+================================+
+ | :attr:`%%` | *n/a* | The literal % character. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%c` | int | A single character, |
+ | | | represented as an C int. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%d` | int | Exactly equivalent to |
+ | | | ``printf("%d")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%u` | unsigned int | Exactly equivalent to |
+ | | | ``printf("%u")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%ld` | long | Exactly equivalent to |
+ | | | ``printf("%ld")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%lu` | unsigned long | Exactly equivalent to |
+ | | | ``printf("%lu")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%zd` | Py_ssize_t | Exactly equivalent to |
+ | | | ``printf("%zd")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%zu` | size_t | Exactly equivalent to |
+ | | | ``printf("%zu")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%i` | int | Exactly equivalent to |
+ | | | ``printf("%i")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%x` | int | Exactly equivalent to |
+ | | | ``printf("%x")``. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%s` | char\* | A null-terminated C character |
+ | | | array. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%p` | void\* | The hex representation of a C |
+ | | | pointer. Mostly equivalent to |
+ | | | ``printf("%p")`` except that |
+ | | | it is guaranteed to start with |
+ | | | the literal ``0x`` regardless |
+ | | | of what the platform's |
+ | | | ``printf`` yields. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%U` | PyObject\* | A unicode object. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%V` | PyObject\*, char \* | A unicode object (which may be |
+ | | | *NULL*) and a null-terminated |
+ | | | C character array as a second |
+ | | | parameter (which will be used, |
+ | | | if the first parameter is |
+ | | | *NULL*). |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%S` | PyObject\* | The result of calling |
+ | | | :func:`PyObject_Unicode`. |
+ +-------------------+---------------------+--------------------------------+
+ | :attr:`%R` | PyObject\* | The result of calling |
+ | | | :func:`PyObject_Repr`. |
+ +-------------------+---------------------+--------------------------------+
+
+ An unrecognized format character causes all the rest of the format string to be
+ copied as-is to the result string, and any extra arguments discarded.
+
+ .. versionadded:: 3.0
+
+
+.. cfunction:: PyObject* PyUnicode_FromFormatV(const char *format, va_list vargs)
+
+ Identical to :func:`PyUnicode_FromFormat` except that it takes exactly two
+ arguments.
+
+ .. versionadded:: 3.0
+
+
+.. cfunction:: Py_UNICODE* PyUnicode_AsUnicode(PyObject *unicode)
+
+ Return a read-only pointer to the Unicode object's internal :ctype:`Py_UNICODE`
+ buffer, *NULL* if *unicode* is not a Unicode object.
+
+
+.. cfunction:: Py_ssize_t PyUnicode_GetSize(PyObject *unicode)
+
+ Return the length of the Unicode object.
+
+
+.. cfunction:: PyObject* PyUnicode_FromEncodedObject(PyObject *obj, const char *encoding, const char *errors)
+
+ Coerce an encoded object *obj* to an Unicode object and return a reference with
+ incremented refcount.
+
+ String and other char buffer compatible objects are decoded according to the
+ given encoding and using the error handling defined by errors. Both can be
+ *NULL* to have the interface use the default values (see the next section for
+ details).
+
+ All other objects, including Unicode objects, cause a :exc:`TypeError` to be
+ set.
+
+ The API returns *NULL* if there was an error. The caller is responsible for
+ decref'ing the returned objects.
+
+
+.. cfunction:: PyObject* PyUnicode_FromObject(PyObject *obj)
+
+ Shortcut for ``PyUnicode_FromEncodedObject(obj, NULL, "strict")`` which is used
+ throughout the interpreter whenever coercion to Unicode is needed.
+
+If the platform supports :ctype:`wchar_t` and provides a header file wchar.h,
+Python can interface directly to this type using the following functions.
+Support is optimized if Python's own :ctype:`Py_UNICODE` type is identical to
+the system's :ctype:`wchar_t`.
+
+.. % --- wchar_t support for platforms which support it ---------------------
+
+
+.. cfunction:: PyObject* PyUnicode_FromWideChar(const wchar_t *w, Py_ssize_t size)
+
+ Create a Unicode object from the :ctype:`wchar_t` buffer *w* of the given size.
+ Return *NULL* on failure.
+
+
+.. cfunction:: Py_ssize_t PyUnicode_AsWideChar(PyUnicodeObject *unicode, wchar_t *w, Py_ssize_t size)
+
+ Copy the Unicode object contents into the :ctype:`wchar_t` buffer *w*. At most
+ *size* :ctype:`wchar_t` characters are copied (excluding a possibly trailing
+ 0-termination character). Return the number of :ctype:`wchar_t` characters
+ copied or -1 in case of an error. Note that the resulting :ctype:`wchar_t`
+ string may or may not be 0-terminated. It is the responsibility of the caller
+ to make sure that the :ctype:`wchar_t` string is 0-terminated in case this is
+ required by the application.
+
+
+.. _builtincodecs:
+
+Built-in Codecs
+^^^^^^^^^^^^^^^
+
+Python provides a set of builtin codecs which are written in C for speed. All of
+these codecs are directly usable via the following functions.
+
+Many of the following APIs take two arguments encoding and errors. These
+parameters encoding and errors have the same semantics as the ones of the
+builtin unicode() Unicode object constructor.
+
+Setting encoding to *NULL* causes the default encoding to be used which is
+ASCII. The file system calls should use :cdata:`Py_FileSystemDefaultEncoding`
+as the encoding for file names. This variable should be treated as read-only: On
+some systems, it will be a pointer to a static string, on others, it will change
+at run-time (such as when the application invokes setlocale).
+
+Error handling is set by errors which may also be set to *NULL* meaning to use
+the default handling defined for the codec. Default error handling for all
+builtin codecs is "strict" (:exc:`ValueError` is raised).
+
+The codecs all use a similar interface. Only deviation from the following
+generic ones are documented for simplicity.
+
+These are the generic codec APIs:
+
+.. % --- Generic Codecs -----------------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_Decode(const char *s, Py_ssize_t size, const char *encoding, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the encoded string *s*.
+ *encoding* and *errors* have the same meaning as the parameters of the same name
+ in the :func:`unicode` builtin function. The codec to be used is looked up
+ using the Python codec registry. Return *NULL* if an exception was raised by
+ the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_Encode(const Py_UNICODE *s, Py_ssize_t size, const char *encoding, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size and return a Python
+ string object. *encoding* and *errors* have the same meaning as the parameters
+ of the same name in the Unicode :meth:`encode` method. The codec to be used is
+ looked up using the Python codec registry. Return *NULL* if an exception was
+ raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsEncodedString(PyObject *unicode, const char *encoding, const char *errors)
+
+ Encode a Unicode object and return the result as Python string object.
+ *encoding* and *errors* have the same meaning as the parameters of the same name
+ in the Unicode :meth:`encode` method. The codec to be used is looked up using
+ the Python codec registry. Return *NULL* if an exception was raised by the
+ codec.
+
+These are the UTF-8 codec APIs:
+
+.. % --- UTF-8 Codecs -------------------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeUTF8(const char *s, Py_ssize_t size, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the UTF-8 encoded string
+ *s*. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeUTF8Stateful(const char *s, Py_ssize_t size, const char *errors, Py_ssize_t *consumed)
+
+ If *consumed* is *NULL*, behave like :cfunc:`PyUnicode_DecodeUTF8`. If
+ *consumed* is not *NULL*, trailing incomplete UTF-8 byte sequences will not be
+ treated as an error. Those bytes will not be decoded and the number of bytes
+ that have been decoded will be stored in *consumed*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeUTF8(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using UTF-8 and return a
+ Python string object. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsUTF8String(PyObject *unicode)
+
+ Encode a Unicode objects using UTF-8 and return the result as Python string
+ object. Error handling is "strict". Return *NULL* if an exception was raised
+ by the codec.
+
+These are the UTF-16 codec APIs:
+
+.. % --- UTF-16 Codecs ------------------------------------------------------ */
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeUTF16(const char *s, Py_ssize_t size, const char *errors, int *byteorder)
+
+ Decode *length* bytes from a UTF-16 encoded buffer string and return the
+ corresponding Unicode object. *errors* (if non-*NULL*) defines the error
+ handling. It defaults to "strict".
+
+ If *byteorder* is non-*NULL*, the decoder starts decoding using the given byte
+ order::
+
+ *byteorder == -1: little endian
+ *byteorder == 0: native order
+ *byteorder == 1: big endian
+
+ and then switches if the first two bytes of the input data are a byte order mark
+ (BOM) and the specified byte order is native order. This BOM is not copied into
+ the resulting Unicode string. After completion, *\*byteorder* is set to the
+ current byte order at the.
+
+ If *byteorder* is *NULL*, the codec starts in native order mode.
+
+ Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeUTF16Stateful(const char *s, Py_ssize_t size, const char *errors, int *byteorder, Py_ssize_t *consumed)
+
+ If *consumed* is *NULL*, behave like :cfunc:`PyUnicode_DecodeUTF16`. If
+ *consumed* is not *NULL*, :cfunc:`PyUnicode_DecodeUTF16Stateful` will not treat
+ trailing incomplete UTF-16 byte sequences (such as an odd number of bytes or a
+ split surrogate pair) as an error. Those bytes will not be decoded and the
+ number of bytes that have been decoded will be stored in *consumed*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeUTF16(const Py_UNICODE *s, Py_ssize_t size, const char *errors, int byteorder)
+
+ Return a Python string object holding the UTF-16 encoded value of the Unicode
+ data in *s*. If *byteorder* is not ``0``, output is written according to the
+ following byte order::
+
+ byteorder == -1: little endian
+ byteorder == 0: native byte order (writes a BOM mark)
+ byteorder == 1: big endian
+
+ If byteorder is ``0``, the output string will always start with the Unicode BOM
+ mark (U+FEFF). In the other two modes, no BOM mark is prepended.
+
+ If *Py_UNICODE_WIDE* is defined, a single :ctype:`Py_UNICODE` value may get
+ represented as a surrogate pair. If it is not defined, each :ctype:`Py_UNICODE`
+ values is interpreted as an UCS-2 character.
+
+ Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsUTF16String(PyObject *unicode)
+
+ Return a Python string using the UTF-16 encoding in native byte order. The
+ string always starts with a BOM mark. Error handling is "strict". Return
+ *NULL* if an exception was raised by the codec.
+
+These are the "Unicode Escape" codec APIs:
+
+.. % --- Unicode-Escape Codecs ----------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeUnicodeEscape(const char *s, Py_ssize_t size, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the Unicode-Escape encoded
+ string *s*. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeUnicodeEscape(const Py_UNICODE *s, Py_ssize_t size)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using Unicode-Escape and
+ return a Python string object. Return *NULL* if an exception was raised by the
+ codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
+
+ Encode a Unicode objects using Unicode-Escape and return the result as Python
+ string object. Error handling is "strict". Return *NULL* if an exception was
+ raised by the codec.
+
+These are the "Raw Unicode Escape" codec APIs:
+
+.. % --- Raw-Unicode-Escape Codecs ------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeRawUnicodeEscape(const char *s, Py_ssize_t size, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the Raw-Unicode-Escape
+ encoded string *s*. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeRawUnicodeEscape(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using Raw-Unicode-Escape
+ and return a Python string object. Return *NULL* if an exception was raised by
+ the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsRawUnicodeEscapeString(PyObject *unicode)
+
+ Encode a Unicode objects using Raw-Unicode-Escape and return the result as
+ Python string object. Error handling is "strict". Return *NULL* if an exception
+ was raised by the codec.
+
+These are the Latin-1 codec APIs: Latin-1 corresponds to the first 256 Unicode
+ordinals and only these are accepted by the codecs during encoding.
+
+.. % --- Latin-1 Codecs -----------------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeLatin1(const char *s, Py_ssize_t size, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the Latin-1 encoded string
+ *s*. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeLatin1(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using Latin-1 and return
+ a Python string object. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsLatin1String(PyObject *unicode)
+
+ Encode a Unicode objects using Latin-1 and return the result as Python string
+ object. Error handling is "strict". Return *NULL* if an exception was raised
+ by the codec.
+
+These are the ASCII codec APIs. Only 7-bit ASCII data is accepted. All other
+codes generate errors.
+
+.. % --- ASCII Codecs -------------------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeASCII(const char *s, Py_ssize_t size, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the ASCII encoded string
+ *s*. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeASCII(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using ASCII and return a
+ Python string object. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsASCIIString(PyObject *unicode)
+
+ Encode a Unicode objects using ASCII and return the result as Python string
+ object. Error handling is "strict". Return *NULL* if an exception was raised
+ by the codec.
+
+These are the mapping codec APIs:
+
+.. % --- Character Map Codecs -----------------------------------------------
+
+This codec is special in that it can be used to implement many different codecs
+(and this is in fact what was done to obtain most of the standard codecs
+included in the :mod:`encodings` package). The codec uses mapping to encode and
+decode characters.
+
+Decoding mappings must map single string characters to single Unicode
+characters, integers (which are then interpreted as Unicode ordinals) or None
+(meaning "undefined mapping" and causing an error).
+
+Encoding mappings must map single Unicode characters to single string
+characters, integers (which are then interpreted as Latin-1 ordinals) or None
+(meaning "undefined mapping" and causing an error).
+
+The mapping objects provided must only support the __getitem__ mapping
+interface.
+
+If a character lookup fails with a LookupError, the character is copied as-is
+meaning that its ordinal value will be interpreted as Unicode or Latin-1 ordinal
+resp. Because of this, mappings only need to contain those mappings which map
+characters to different code points.
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeCharmap(const char *s, Py_ssize_t size, PyObject *mapping, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the encoded string *s* using
+ the given *mapping* object. Return *NULL* if an exception was raised by the
+ codec. If *mapping* is *NULL* latin-1 decoding will be done. Else it can be a
+ dictionary mapping byte or a unicode string, which is treated as a lookup table.
+ Byte values greater that the length of the string and U+FFFE "characters" are
+ treated as "undefined mapping".
+
+ .. versionchanged:: 2.4
+ Allowed unicode string as mapping argument.
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeCharmap(const Py_UNICODE *s, Py_ssize_t size, PyObject *mapping, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using the given
+ *mapping* object and return a Python string object. Return *NULL* if an
+ exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsCharmapString(PyObject *unicode, PyObject *mapping)
+
+ Encode a Unicode objects using the given *mapping* object and return the result
+ as Python string object. Error handling is "strict". Return *NULL* if an
+ exception was raised by the codec.
+
+The following codec API is special in that maps Unicode to Unicode.
+
+
+.. cfunction:: PyObject* PyUnicode_TranslateCharmap(const Py_UNICODE *s, Py_ssize_t size, PyObject *table, const char *errors)
+
+ Translate a :ctype:`Py_UNICODE` buffer of the given length by applying a
+ character mapping *table* to it and return the resulting Unicode object. Return
+ *NULL* when an exception was raised by the codec.
+
+ The *mapping* table must map Unicode ordinal integers to Unicode ordinal
+ integers or None (causing deletion of the character).
+
+ Mapping tables need only provide the :meth:`__getitem__` interface; dictionaries
+ and sequences work well. Unmapped character ordinals (ones which cause a
+ :exc:`LookupError`) are left untouched and are copied as-is.
+
+These are the MBCS codec APIs. They are currently only available on Windows and
+use the Win32 MBCS converters to implement the conversions. Note that MBCS (or
+DBCS) is a class of encodings, not just one. The target encoding is defined by
+the user settings on the machine running the codec.
+
+.. % --- MBCS codecs for Windows --------------------------------------------
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeMBCS(const char *s, Py_ssize_t size, const char *errors)
+
+ Create a Unicode object by decoding *size* bytes of the MBCS encoded string *s*.
+ Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_DecodeMBCSStateful(const char *s, int size, const char *errors, int *consumed)
+
+ If *consumed* is *NULL*, behave like :cfunc:`PyUnicode_DecodeMBCS`. If
+ *consumed* is not *NULL*, :cfunc:`PyUnicode_DecodeMBCSStateful` will not decode
+ trailing lead byte and the number of bytes that have been decoded will be stored
+ in *consumed*.
+
+ .. versionadded:: 2.5
+
+
+.. cfunction:: PyObject* PyUnicode_EncodeMBCS(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
+
+ Encode the :ctype:`Py_UNICODE` buffer of the given size using MBCS and return a
+ Python string object. Return *NULL* if an exception was raised by the codec.
+
+
+.. cfunction:: PyObject* PyUnicode_AsMBCSString(PyObject *unicode)
+
+ Encode a Unicode objects using MBCS and return the result as Python string
+ object. Error handling is "strict". Return *NULL* if an exception was raised
+ by the codec.
+
+.. % --- Methods & Slots ----------------------------------------------------
+
+
+.. _unicodemethodsandslots:
+
+Methods and Slot Functions
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following APIs are capable of handling Unicode objects and strings on input
+(we refer to them as strings in the descriptions) and return Unicode objects or
+integers as appropriate.
+
+They all return *NULL* or ``-1`` if an exception occurs.
+
+
+.. cfunction:: PyObject* PyUnicode_Concat(PyObject *left, PyObject *right)
+
+ Concat two strings giving a new Unicode string.
+
+
+.. cfunction:: PyObject* PyUnicode_Split(PyObject *s, PyObject *sep, Py_ssize_t maxsplit)
+
+ Split a string giving a list of Unicode strings. If sep is *NULL*, splitting
+ will be done at all whitespace substrings. Otherwise, splits occur at the given
+ separator. At most *maxsplit* splits will be done. If negative, no limit is
+ set. Separators are not included in the resulting list.
+
+
+.. cfunction:: PyObject* PyUnicode_Splitlines(PyObject *s, int keepend)
+
+ Split a Unicode string at line breaks, returning a list of Unicode strings.
+ CRLF is considered to be one line break. If *keepend* is 0, the Line break
+ characters are not included in the resulting strings.
+
+
+.. cfunction:: PyObject* PyUnicode_Translate(PyObject *str, PyObject *table, const char *errors)
+
+ Translate a string by applying a character mapping table to it and return the
+ resulting Unicode object.
+
+ The mapping table must map Unicode ordinal integers to Unicode ordinal integers
+ or None (causing deletion of the character).
+
+ Mapping tables need only provide the :meth:`__getitem__` interface; dictionaries
+ and sequences work well. Unmapped character ordinals (ones which cause a
+ :exc:`LookupError`) are left untouched and are copied as-is.
+
+ *errors* has the usual meaning for codecs. It may be *NULL* which indicates to
+ use the default error handling.
+
+
+.. cfunction:: PyObject* PyUnicode_Join(PyObject *separator, PyObject *seq)
+
+ Join a sequence of strings using the given separator and return the resulting
+ Unicode string.
+
+
+.. cfunction:: int PyUnicode_Tailmatch(PyObject *str, PyObject *substr, Py_ssize_t start, Py_ssize_t end, int direction)
+
+ Return 1 if *substr* matches *str*[*start*:*end*] at the given tail end
+ (*direction* == -1 means to do a prefix match, *direction* == 1 a suffix match),
+ 0 otherwise. Return ``-1`` if an error occurred.
+
+
+.. cfunction:: Py_ssize_t PyUnicode_Find(PyObject *str, PyObject *substr, Py_ssize_t start, Py_ssize_t end, int direction)
+
+ Return the first position of *substr* in *str*[*start*:*end*] using the given
+ *direction* (*direction* == 1 means to do a forward search, *direction* == -1 a
+ backward search). The return value is the index of the first match; a value of
+ ``-1`` indicates that no match was found, and ``-2`` indicates that an error
+ occurred and an exception has been set.
+
+
+.. cfunction:: Py_ssize_t PyUnicode_Count(PyObject *str, PyObject *substr, Py_ssize_t start, Py_ssize_t end)
+
+ Return the number of non-overlapping occurrences of *substr* in
+ ``str[start:end]``. Return ``-1`` if an error occurred.
+
+
+.. cfunction:: PyObject* PyUnicode_Replace(PyObject *str, PyObject *substr, PyObject *replstr, Py_ssize_t maxcount)
+
+ Replace at most *maxcount* occurrences of *substr* in *str* with *replstr* and
+ return the resulting Unicode object. *maxcount* == -1 means replace all
+ occurrences.
+
+
+.. cfunction:: int PyUnicode_Compare(PyObject *left, PyObject *right)
+
+ Compare two strings and return -1, 0, 1 for less than, equal, and greater than,
+ respectively.
+
+
+.. cfunction:: int PyUnicode_RichCompare(PyObject *left, PyObject *right, int op)
+
+ Rich compare two unicode strings and return one of the following:
+
+ * ``NULL`` in case an exception was raised
+ * :const:`Py_True` or :const:`Py_False` for successful comparisons
+ * :const:`Py_NotImplemented` in case the type combination is unknown
+
+ Note that :const:`Py_EQ` and :const:`Py_NE` comparisons can cause a
+ :exc:`UnicodeWarning` in case the conversion of the arguments to Unicode fails
+ with a :exc:`UnicodeDecodeError`.
+
+ Possible values for *op* are :const:`Py_GT`, :const:`Py_GE`, :const:`Py_EQ`,
+ :const:`Py_NE`, :const:`Py_LT`, and :const:`Py_LE`.
+
+
+.. cfunction:: PyObject* PyUnicode_Format(PyObject *format, PyObject *args)
+
+ Return a new string object from *format* and *args*; this is analogous to
+ ``format % args``. The *args* argument must be a tuple.
+
+
+.. cfunction:: int PyUnicode_Contains(PyObject *container, PyObject *element)
+
+ Check whether *element* is contained in *container* and return true or false
+ accordingly.
+
+ *element* has to coerce to a one element Unicode string. ``-1`` is returned if
+ there was an error.
+
+
+.. cfunction:: void PyUnicode_InternInPlace(PyObject **string)
+
+ Intern the argument *\*string* in place. The argument must be the address of a
+ pointer variable pointing to a Python unicode string object. If there is an
+ existing interned string that is the same as *\*string*, it sets *\*string* to
+ it (decrementing the reference count of the old string object and incrementing
+ the reference count of the interned string object), otherwise it leaves
+ *\*string* alone and interns it (incrementing its reference count).
+ (Clarification: even though there is a lot of talk about reference counts, think
+ of this function as reference-count-neutral; you own the object after the call
+ if and only if you owned it before the call.)
+
+
+.. cfunction:: PyObject* PyUnicode_InternFromString(const char *v)
+
+ A combination of :cfunc:`PyUnicode_FromString` and
+ :cfunc:`PyUnicode_InternInPlace`, returning either a new unicode string object
+ that has been interned, or a new ("owned") reference to an earlier interned
+ string object with the same value.
+
+
+.. _bufferobjects:
+
+Buffer Objects
+--------------
+
+.. sectionauthor:: Greg Stein <gstein@lyra.org>
+
+
+.. index::
+ object: buffer
+ single: buffer interface
+
+Python objects implemented in C can export a group of functions called the
+"buffer interface." These functions can be used by an object to expose its data
+in a raw, byte-oriented format. Clients of the object can use the buffer
+interface to access the object data directly, without needing to copy it first.
+
+Two examples of objects that support the buffer interface are strings and
+arrays. The string object exposes the character contents in the buffer
+interface's byte-oriented form. An array can also expose its contents, but it
+should be noted that array elements may be multi-byte values.
+
+An example user of the buffer interface is the file object's :meth:`write`
+method. Any object that can export a series of bytes through the buffer
+interface can be written to a file. There are a number of format codes to
+:cfunc:`PyArg_ParseTuple` that operate against an object's buffer interface,
+returning data from the target object.
+
+.. index:: single: PyBufferProcs
+
+More information on the buffer interface is provided in the section
+:ref:`buffer-structs`, under the description for :ctype:`PyBufferProcs`.
+
+A "buffer object" is defined in the :file:`bufferobject.h` header (included by
+:file:`Python.h`). These objects look very similar to string objects at the
+Python programming level: they support slicing, indexing, concatenation, and
+some other standard string operations. However, their data can come from one of
+two sources: from a block of memory, or from another object which exports the
+buffer interface.
+
+Buffer objects are useful as a way to expose the data from another object's
+buffer interface to the Python programmer. They can also be used as a zero-copy
+slicing mechanism. Using their ability to reference a block of memory, it is
+possible to expose any data to the Python programmer quite easily. The memory
+could be a large, constant array in a C extension, it could be a raw block of
+memory for manipulation before passing to an operating system library, or it
+could be used to pass around structured data in its native, in-memory format.
+
+
+.. ctype:: PyBufferObject
+
+ This subtype of :ctype:`PyObject` represents a buffer object.
+
+
+.. cvar:: PyTypeObject PyBuffer_Type
+
+ .. index:: single: BufferType (in module types)
+
+ The instance of :ctype:`PyTypeObject` which represents the Python buffer type;
+ it is the same object as ``buffer`` and ``types.BufferType`` in the Python
+ layer. .
+
+
+.. cvar:: int Py_END_OF_BUFFER
+
+ This constant may be passed as the *size* parameter to
+ :cfunc:`PyBuffer_FromObject` or :cfunc:`PyBuffer_FromReadWriteObject`. It
+ indicates that the new :ctype:`PyBufferObject` should refer to *base* object
+ from the specified *offset* to the end of its exported buffer. Using this
+ enables the caller to avoid querying the *base* object for its length.
+
+
+.. cfunction:: int PyBuffer_Check(PyObject *p)
+
+ Return true if the argument has type :cdata:`PyBuffer_Type`.
+
+
+.. cfunction:: PyObject* PyBuffer_FromObject(PyObject *base, Py_ssize_t offset, Py_ssize_t size)
+
+ Return a new read-only buffer object. This raises :exc:`TypeError` if *base*
+ doesn't support the read-only buffer protocol or doesn't provide exactly one
+ buffer segment, or it raises :exc:`ValueError` if *offset* is less than zero.
+ The buffer will hold a reference to the *base* object, and the buffer's contents
+ will refer to the *base* object's buffer interface, starting as position
+ *offset* and extending for *size* bytes. If *size* is :const:`Py_END_OF_BUFFER`,
+ then the new buffer's contents extend to the length of the *base* object's
+ exported buffer data.
+
+
+.. cfunction:: PyObject* PyBuffer_FromReadWriteObject(PyObject *base, Py_ssize_t offset, Py_ssize_t size)
+
+ Return a new writable buffer object. Parameters and exceptions are similar to
+ those for :cfunc:`PyBuffer_FromObject`. If the *base* object does not export
+ the writeable buffer protocol, then :exc:`TypeError` is raised.
+
+
+.. cfunction:: PyObject* PyBuffer_FromMemory(void *ptr, Py_ssize_t size)
+
+ Return a new read-only buffer object that reads from a specified location in
+ memory, with a specified size. The caller is responsible for ensuring that the
+ memory buffer, passed in as *ptr*, is not deallocated while the returned buffer
+ object exists. Raises :exc:`ValueError` if *size* is less than zero. Note that
+ :const:`Py_END_OF_BUFFER` may *not* be passed for the *size* parameter;
+ :exc:`ValueError` will be raised in that case.
+
+
+.. cfunction:: PyObject* PyBuffer_FromReadWriteMemory(void *ptr, Py_ssize_t size)
+
+ Similar to :cfunc:`PyBuffer_FromMemory`, but the returned buffer is writable.
+
+
+.. cfunction:: PyObject* PyBuffer_New(Py_ssize_t size)
+
+ Return a new writable buffer object that maintains its own memory buffer of
+ *size* bytes. :exc:`ValueError` is returned if *size* is not zero or positive.
+ Note that the memory buffer (as returned by :cfunc:`PyObject_AsWriteBuffer`) is
+ not specifically aligned.
+
+
+.. _tupleobjects:
+
+Tuple Objects
+-------------
+
+.. index:: object: tuple
+
+
+.. ctype:: PyTupleObject
+
+ This subtype of :ctype:`PyObject` represents a Python tuple object.
+
+
+.. cvar:: PyTypeObject PyTuple_Type
+
+ .. index:: single: TupleType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python tuple type; it is
+ the same object as ``tuple`` and ``types.TupleType`` in the Python layer..
+
+
+.. cfunction:: int PyTuple_Check(PyObject *p)
+
+ Return true if *p* is a tuple object or an instance of a subtype of the tuple
+ type.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyTuple_CheckExact(PyObject *p)
+
+ Return true if *p* is a tuple object, but not an instance of a subtype of the
+ tuple type.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyTuple_New(Py_ssize_t len)
+
+ Return a new tuple object of size *len*, or *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyTuple_Pack(Py_ssize_t n, ...)
+
+ Return a new tuple object of size *n*, or *NULL* on failure. The tuple values
+ are initialized to the subsequent *n* C arguments pointing to Python objects.
+ ``PyTuple_Pack(2, a, b)`` is equivalent to ``Py_BuildValue("(OO)", a, b)``.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyTuple_Size(PyObject *p)
+
+ Take a pointer to a tuple object, and return the size of that tuple.
+
+
+.. cfunction:: int PyTuple_GET_SIZE(PyObject *p)
+
+ Return the size of the tuple *p*, which must be non-*NULL* and point to a tuple;
+ no error checking is performed.
+
+
+.. cfunction:: PyObject* PyTuple_GetItem(PyObject *p, Py_ssize_t pos)
+
+ Return the object at position *pos* in the tuple pointed to by *p*. If *pos* is
+ out of bounds, return *NULL* and sets an :exc:`IndexError` exception.
+
+
+.. cfunction:: PyObject* PyTuple_GET_ITEM(PyObject *p, Py_ssize_t pos)
+
+ Like :cfunc:`PyTuple_GetItem`, but does no checking of its arguments.
+
+
+.. cfunction:: PyObject* PyTuple_GetSlice(PyObject *p, Py_ssize_t low, Py_ssize_t high)
+
+ Take a slice of the tuple pointed to by *p* from *low* to *high* and return it
+ as a new tuple.
+
+
+.. cfunction:: int PyTuple_SetItem(PyObject *p, Py_ssize_t pos, PyObject *o)
+
+ Insert a reference to object *o* at position *pos* of the tuple pointed to by
+ *p*. Return ``0`` on success.
+
+ .. note::
+
+ This function "steals" a reference to *o*.
+
+
+.. cfunction:: void PyTuple_SET_ITEM(PyObject *p, Py_ssize_t pos, PyObject *o)
+
+ Like :cfunc:`PyTuple_SetItem`, but does no error checking, and should *only* be
+ used to fill in brand new tuples.
+
+ .. note::
+
+ This function "steals" a reference to *o*.
+
+
+.. cfunction:: int _PyTuple_Resize(PyObject **p, Py_ssize_t newsize)
+
+ Can be used to resize a tuple. *newsize* will be the new length of the tuple.
+ Because tuples are *supposed* to be immutable, this should only be used if there
+ is only one reference to the object. Do *not* use this if the tuple may already
+ be known to some other part of the code. The tuple will always grow or shrink
+ at the end. Think of this as destroying the old tuple and creating a new one,
+ only more efficiently. Returns ``0`` on success. Client code should never
+ assume that the resulting value of ``*p`` will be the same as before calling
+ this function. If the object referenced by ``*p`` is replaced, the original
+ ``*p`` is destroyed. On failure, returns ``-1`` and sets ``*p`` to *NULL*, and
+ raises :exc:`MemoryError` or :exc:`SystemError`.
+
+ .. versionchanged:: 2.2
+ Removed unused third parameter, *last_is_sticky*.
+
+
+.. _listobjects:
+
+List Objects
+------------
+
+.. index:: object: list
+
+
+.. ctype:: PyListObject
+
+ This subtype of :ctype:`PyObject` represents a Python list object.
+
+
+.. cvar:: PyTypeObject PyList_Type
+
+ .. index:: single: ListType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python list type. This is
+ the same object as ``list`` and ``types.ListType`` in the Python layer.
+
+
+.. cfunction:: int PyList_Check(PyObject *p)
+
+ Return true if *p* is a list object or an instance of a subtype of the list
+ type.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyList_CheckExact(PyObject *p)
+
+ Return true if *p* is a list object, but not an instance of a subtype of the
+ list type.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyList_New(Py_ssize_t len)
+
+ Return a new list of length *len* on success, or *NULL* on failure.
+
+ .. note::
+
+ If *length* is greater than zero, the returned list object's items are set to
+ ``NULL``. Thus you cannot use abstract API functions such as
+ :cfunc:`PySequence_SetItem` or expose the object to Python code before setting
+ all items to a real object with :cfunc:`PyList_SetItem`.
+
+
+.. cfunction:: Py_ssize_t PyList_Size(PyObject *list)
+
+ .. index:: builtin: len
+
+ Return the length of the list object in *list*; this is equivalent to
+ ``len(list)`` on a list object.
+
+
+.. cfunction:: Py_ssize_t PyList_GET_SIZE(PyObject *list)
+
+ Macro form of :cfunc:`PyList_Size` without error checking.
+
+
+.. cfunction:: PyObject* PyList_GetItem(PyObject *list, Py_ssize_t index)
+
+ Return the object at position *pos* in the list pointed to by *p*. The position
+ must be positive, indexing from the end of the list is not supported. If *pos*
+ is out of bounds, return *NULL* and set an :exc:`IndexError` exception.
+
+
+.. cfunction:: PyObject* PyList_GET_ITEM(PyObject *list, Py_ssize_t i)
+
+ Macro form of :cfunc:`PyList_GetItem` without error checking.
+
+
+.. cfunction:: int PyList_SetItem(PyObject *list, Py_ssize_t index, PyObject *item)
+
+ Set the item at index *index* in list to *item*. Return ``0`` on success or
+ ``-1`` on failure.
+
+ .. note::
+
+ This function "steals" a reference to *item* and discards a reference to an item
+ already in the list at the affected position.
+
+
+.. cfunction:: void PyList_SET_ITEM(PyObject *list, Py_ssize_t i, PyObject *o)
+
+ Macro form of :cfunc:`PyList_SetItem` without error checking. This is normally
+ only used to fill in new lists where there is no previous content.
+
+ .. note::
+
+ This function "steals" a reference to *item*, and, unlike
+ :cfunc:`PyList_SetItem`, does *not* discard a reference to any item that it
+ being replaced; any reference in *list* at position *i* will be leaked.
+
+
+.. cfunction:: int PyList_Insert(PyObject *list, Py_ssize_t index, PyObject *item)
+
+ Insert the item *item* into list *list* in front of index *index*. Return ``0``
+ if successful; return ``-1`` and set an exception if unsuccessful. Analogous to
+ ``list.insert(index, item)``.
+
+
+.. cfunction:: int PyList_Append(PyObject *list, PyObject *item)
+
+ Append the object *item* at the end of list *list*. Return ``0`` if successful;
+ return ``-1`` and set an exception if unsuccessful. Analogous to
+ ``list.append(item)``.
+
+
+.. cfunction:: PyObject* PyList_GetSlice(PyObject *list, Py_ssize_t low, Py_ssize_t high)
+
+ Return a list of the objects in *list* containing the objects *between* *low*
+ and *high*. Return *NULL* and set an exception if unsuccessful. Analogous to
+ ``list[low:high]``.
+
+
+.. cfunction:: int PyList_SetSlice(PyObject *list, Py_ssize_t low, Py_ssize_t high, PyObject *itemlist)
+
+ Set the slice of *list* between *low* and *high* to the contents of *itemlist*.
+ Analogous to ``list[low:high] = itemlist``. The *itemlist* may be *NULL*,
+ indicating the assignment of an empty list (slice deletion). Return ``0`` on
+ success, ``-1`` on failure.
+
+
+.. cfunction:: int PyList_Sort(PyObject *list)
+
+ Sort the items of *list* in place. Return ``0`` on success, ``-1`` on failure.
+ This is equivalent to ``list.sort()``.
+
+
+.. cfunction:: int PyList_Reverse(PyObject *list)
+
+ Reverse the items of *list* in place. Return ``0`` on success, ``-1`` on
+ failure. This is the equivalent of ``list.reverse()``.
+
+
+.. cfunction:: PyObject* PyList_AsTuple(PyObject *list)
+
+ .. index:: builtin: tuple
+
+ Return a new tuple object containing the contents of *list*; equivalent to
+ ``tuple(list)``.
+
+
+.. _mapobjects:
+
+Mapping Objects
+===============
+
+.. index:: object: mapping
+
+
+.. _dictobjects:
+
+Dictionary Objects
+------------------
+
+.. index:: object: dictionary
+
+
+.. ctype:: PyDictObject
+
+ This subtype of :ctype:`PyObject` represents a Python dictionary object.
+
+
+.. cvar:: PyTypeObject PyDict_Type
+
+ .. index::
+ single: DictType (in module types)
+ single: DictionaryType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python dictionary type.
+ This is exposed to Python programs as ``dict`` and ``types.DictType``.
+
+
+.. cfunction:: int PyDict_Check(PyObject *p)
+
+ Return true if *p* is a dict object or an instance of a subtype of the dict
+ type.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyDict_CheckExact(PyObject *p)
+
+ Return true if *p* is a dict object, but not an instance of a subtype of the
+ dict type.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyDict_New()
+
+ Return a new empty dictionary, or *NULL* on failure.
+
+
+.. cfunction:: PyObject* PyDictProxy_New(PyObject *dict)
+
+ Return a proxy object for a mapping which enforces read-only behavior. This is
+ normally used to create a proxy to prevent modification of the dictionary for
+ non-dynamic class types.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: void PyDict_Clear(PyObject *p)
+
+ Empty an existing dictionary of all key-value pairs.
+
+
+.. cfunction:: int PyDict_Contains(PyObject *p, PyObject *key)
+
+ Determine if dictionary *p* contains *key*. If an item in *p* is matches *key*,
+ return ``1``, otherwise return ``0``. On error, return ``-1``. This is
+ equivalent to the Python expression ``key in p``.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyDict_Copy(PyObject *p)
+
+ Return a new dictionary that contains the same key-value pairs as *p*.
+
+ .. versionadded:: 1.6
+
+
+.. cfunction:: int PyDict_SetItem(PyObject *p, PyObject *key, PyObject *val)
+
+ Insert *value* into the dictionary *p* with a key of *key*. *key* must be
+ hashable; if it isn't, :exc:`TypeError` will be raised. Return ``0`` on success
+ or ``-1`` on failure.
+
+
+.. cfunction:: int PyDict_SetItemString(PyObject *p, const char *key, PyObject *val)
+
+ .. index:: single: PyString_FromString()
+
+ Insert *value* into the dictionary *p* using *key* as a key. *key* should be a
+ :ctype:`char\*`. The key object is created using ``PyString_FromString(key)``.
+ Return ``0`` on success or ``-1`` on failure.
+
+
+.. cfunction:: int PyDict_DelItem(PyObject *p, PyObject *key)
+
+ Remove the entry in dictionary *p* with key *key*. *key* must be hashable; if it
+ isn't, :exc:`TypeError` is raised. Return ``0`` on success or ``-1`` on
+ failure.
+
+
+.. cfunction:: int PyDict_DelItemString(PyObject *p, char *key)
+
+ Remove the entry in dictionary *p* which has a key specified by the string
+ *key*. Return ``0`` on success or ``-1`` on failure.
+
+
+.. cfunction:: PyObject* PyDict_GetItem(PyObject *p, PyObject *key)
+
+ Return the object from dictionary *p* which has a key *key*. Return *NULL* if
+ the key *key* is not present, but *without* setting an exception.
+
+
+.. cfunction:: PyObject* PyDict_GetItemString(PyObject *p, const char *key)
+
+ This is the same as :cfunc:`PyDict_GetItem`, but *key* is specified as a
+ :ctype:`char\*`, rather than a :ctype:`PyObject\*`.
+
+
+.. cfunction:: PyObject* PyDict_Items(PyObject *p)
+
+ Return a :ctype:`PyListObject` containing all the items from the dictionary, as
+ in the dictionary method :meth:`dict.items`.
+
+
+.. cfunction:: PyObject* PyDict_Keys(PyObject *p)
+
+ Return a :ctype:`PyListObject` containing all the keys from the dictionary, as
+ in the dictionary method :meth:`dict.keys`.
+
+
+.. cfunction:: PyObject* PyDict_Values(PyObject *p)
+
+ Return a :ctype:`PyListObject` containing all the values from the dictionary
+ *p*, as in the dictionary method :meth:`dict.values`.
+
+
+.. cfunction:: Py_ssize_t PyDict_Size(PyObject *p)
+
+ .. index:: builtin: len
+
+ Return the number of items in the dictionary. This is equivalent to ``len(p)``
+ on a dictionary.
+
+
+.. cfunction:: int PyDict_Next(PyObject *p, Py_ssize_t *ppos, PyObject **pkey, PyObject **pvalue)
+
+ Iterate over all key-value pairs in the dictionary *p*. The :ctype:`int`
+ referred to by *ppos* must be initialized to ``0`` prior to the first call to
+ this function to start the iteration; the function returns true for each pair in
+ the dictionary, and false once all pairs have been reported. The parameters
+ *pkey* and *pvalue* should either point to :ctype:`PyObject\*` variables that
+ will be filled in with each key and value, respectively, or may be *NULL*. Any
+ references returned through them are borrowed. *ppos* should not be altered
+ during iteration. Its value represents offsets within the internal dictionary
+ structure, and since the structure is sparse, the offsets are not consecutive.
+
+ For example::
+
+ PyObject *key, *value;
+ Py_ssize_t pos = 0;
+
+ while (PyDict_Next(self->dict, &pos, &key, &value)) {
+ /* do something interesting with the values... */
+ ...
+ }
+
+ The dictionary *p* should not be mutated during iteration. It is safe (since
+ Python 2.1) to modify the values of the keys as you iterate over the dictionary,
+ but only so long as the set of keys does not change. For example::
+
+ PyObject *key, *value;
+ Py_ssize_t pos = 0;
+
+ while (PyDict_Next(self->dict, &pos, &key, &value)) {
+ int i = PyInt_AS_LONG(value) + 1;
+ PyObject *o = PyInt_FromLong(i);
+ if (o == NULL)
+ return -1;
+ if (PyDict_SetItem(self->dict, key, o) < 0) {
+ Py_DECREF(o);
+ return -1;
+ }
+ Py_DECREF(o);
+ }
+
+
+.. cfunction:: int PyDict_Merge(PyObject *a, PyObject *b, int override)
+
+ Iterate over mapping object *b* adding key-value pairs to dictionary *a*. *b*
+ may be a dictionary, or any object supporting :func:`PyMapping_Keys` and
+ :func:`PyObject_GetItem`. If *override* is true, existing pairs in *a* will be
+ replaced if a matching key is found in *b*, otherwise pairs will only be added
+ if there is not a matching key in *a*. Return ``0`` on success or ``-1`` if an
+ exception was raised.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyDict_Update(PyObject *a, PyObject *b)
+
+ This is the same as ``PyDict_Merge(a, b, 1)`` in C, or ``a.update(b)`` in
+ Python. Return ``0`` on success or ``-1`` if an exception was raised.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyDict_MergeFromSeq2(PyObject *a, PyObject *seq2, int override)
+
+ Update or merge into dictionary *a*, from the key-value pairs in *seq2*. *seq2*
+ must be an iterable object producing iterable objects of length 2, viewed as
+ key-value pairs. In case of duplicate keys, the last wins if *override* is
+ true, else the first wins. Return ``0`` on success or ``-1`` if an exception was
+ raised. Equivalent Python (except for the return value)::
+
+ def PyDict_MergeFromSeq2(a, seq2, override):
+ for key, value in seq2:
+ if override or key not in a:
+ a[key] = value
+
+ .. versionadded:: 2.2
+
+
+.. _otherobjects:
+
+Other Objects
+=============
+
+
+.. _classobjects:
+
+Class Objects
+-------------
+
+.. index:: object: class
+
+Note that the class objects described here represent old-style classes, which
+will go away in Python 3. When creating new types for extension modules, you
+will want to work with type objects (section :ref:`typeobjects`).
+
+
+.. ctype:: PyClassObject
+
+ The C structure of the objects used to describe built-in classes.
+
+
+.. cvar:: PyObject* PyClass_Type
+
+ .. index:: single: ClassType (in module types)
+
+ This is the type object for class objects; it is the same object as
+ ``types.ClassType`` in the Python layer.
+
+
+.. cfunction:: int PyClass_Check(PyObject *o)
+
+ Return true if the object *o* is a class object, including instances of types
+ derived from the standard class object. Return false in all other cases.
+
+
+.. cfunction:: int PyClass_IsSubclass(PyObject *klass, PyObject *base)
+
+ Return true if *klass* is a subclass of *base*. Return false in all other cases.
+
+
+.. _fileobjects:
+
+File Objects
+------------
+
+.. index:: object: file
+
+Python's built-in file objects are implemented entirely on the :ctype:`FILE\*`
+support from the C standard library. This is an implementation detail and may
+change in future releases of Python.
+
+
+.. ctype:: PyFileObject
+
+ This subtype of :ctype:`PyObject` represents a Python file object.
+
+
+.. cvar:: PyTypeObject PyFile_Type
+
+ .. index:: single: FileType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python file type. This is
+ exposed to Python programs as ``file`` and ``types.FileType``.
+
+
+.. cfunction:: int PyFile_Check(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyFileObject` or a subtype of
+ :ctype:`PyFileObject`.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyFile_CheckExact(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyFileObject`, but not a subtype of
+ :ctype:`PyFileObject`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyFile_FromString(char *filename, char *mode)
+
+ .. index:: single: fopen()
+
+ On success, return a new file object that is opened on the file given by
+ *filename*, with a file mode given by *mode*, where *mode* has the same
+ semantics as the standard C routine :cfunc:`fopen`. On failure, return *NULL*.
+
+
+.. cfunction:: PyObject* PyFile_FromFile(FILE *fp, char *name, char *mode, int (*close)(FILE*))
+
+ Create a new :ctype:`PyFileObject` from the already-open standard C file
+ pointer, *fp*. The function *close* will be called when the file should be
+ closed. Return *NULL* on failure.
+
+
+.. cfunction:: FILE* PyFile_AsFile(PyObject *p)
+
+ Return the file object associated with *p* as a :ctype:`FILE\*`.
+
+
+.. cfunction:: PyObject* PyFile_GetLine(PyObject *p, int n)
+
+ .. index:: single: EOFError (built-in exception)
+
+ Equivalent to ``p.readline([n])``, this function reads one line from the
+ object *p*. *p* may be a file object or any object with a :meth:`readline`
+ method. If *n* is ``0``, exactly one line is read, regardless of the length of
+ the line. If *n* is greater than ``0``, no more than *n* bytes will be read
+ from the file; a partial line can be returned. In both cases, an empty string
+ is returned if the end of the file is reached immediately. If *n* is less than
+ ``0``, however, one line is read regardless of length, but :exc:`EOFError` is
+ raised if the end of the file is reached immediately.
+
+
+.. cfunction:: PyObject* PyFile_Name(PyObject *p)
+
+ Return the name of the file specified by *p* as a string object.
+
+
+.. cfunction:: void PyFile_SetBufSize(PyFileObject *p, int n)
+
+ .. index:: single: setvbuf()
+
+ Available on systems with :cfunc:`setvbuf` only. This should only be called
+ immediately after file object creation.
+
+
+.. cfunction:: int PyFile_Encoding(PyFileObject *p, char *enc)
+
+ Set the file's encoding for Unicode output to *enc*. Return 1 on success and 0
+ on failure.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: int PyFile_SoftSpace(PyObject *p, int newflag)
+
+ .. index:: single: softspace (file attribute)
+
+ This function exists for internal use by the interpreter. Set the
+ :attr:`softspace` attribute of *p* to *newflag* and return the previous value.
+ *p* does not have to be a file object for this function to work properly; any
+ object is supported (thought its only interesting if the :attr:`softspace`
+ attribute can be set). This function clears any errors, and will return ``0``
+ as the previous value if the attribute either does not exist or if there were
+ errors in retrieving it. There is no way to detect errors from this function,
+ but doing so should not be needed.
+
+
+.. cfunction:: int PyFile_WriteObject(PyObject *obj, PyObject *p, int flags)
+
+ .. index:: single: Py_PRINT_RAW
+
+ Write object *obj* to file object *p*. The only supported flag for *flags* is
+ :const:`Py_PRINT_RAW`; if given, the :func:`str` of the object is written
+ instead of the :func:`repr`. Return ``0`` on success or ``-1`` on failure; the
+ appropriate exception will be set.
+
+
+.. cfunction:: int PyFile_WriteString(const char *s, PyObject *p)
+
+ Write string *s* to file object *p*. Return ``0`` on success or ``-1`` on
+ failure; the appropriate exception will be set.
+
+
+.. _instanceobjects:
+
+Instance Objects
+----------------
+
+.. index:: object: instance
+
+There are very few functions specific to instance objects.
+
+
+.. cvar:: PyTypeObject PyInstance_Type
+
+ Type object for class instances.
+
+
+.. cfunction:: int PyInstance_Check(PyObject *obj)
+
+ Return true if *obj* is an instance.
+
+
+.. cfunction:: PyObject* PyInstance_New(PyObject *class, PyObject *arg, PyObject *kw)
+
+ Create a new instance of a specific class. The parameters *arg* and *kw* are
+ used as the positional and keyword parameters to the object's constructor.
+
+
+.. cfunction:: PyObject* PyInstance_NewRaw(PyObject *class, PyObject *dict)
+
+ Create a new instance of a specific class without calling its constructor.
+ *class* is the class of new object. The *dict* parameter will be used as the
+ object's :attr:`__dict__`; if *NULL*, a new dictionary will be created for the
+ instance.
+
+
+.. _function-objects:
+
+Function Objects
+----------------
+
+.. index:: object: function
+
+There are a few functions specific to Python functions.
+
+
+.. ctype:: PyFunctionObject
+
+ The C structure used for functions.
+
+
+.. cvar:: PyTypeObject PyFunction_Type
+
+ .. index:: single: MethodType (in module types)
+
+ This is an instance of :ctype:`PyTypeObject` and represents the Python function
+ type. It is exposed to Python programmers as ``types.FunctionType``.
+
+
+.. cfunction:: int PyFunction_Check(PyObject *o)
+
+ Return true if *o* is a function object (has type :cdata:`PyFunction_Type`).
+ The parameter must not be *NULL*.
+
+
+.. cfunction:: PyObject* PyFunction_New(PyObject *code, PyObject *globals)
+
+ Return a new function object associated with the code object *code*. *globals*
+ must be a dictionary with the global variables accessible to the function.
+
+ The function's docstring, name and *__module__* are retrieved from the code
+ object, the argument defaults and closure are set to *NULL*.
+
+
+.. cfunction:: PyObject* PyFunction_GetCode(PyObject *op)
+
+ Return the code object associated with the function object *op*.
+
+
+.. cfunction:: PyObject* PyFunction_GetGlobals(PyObject *op)
+
+ Return the globals dictionary associated with the function object *op*.
+
+
+.. cfunction:: PyObject* PyFunction_GetModule(PyObject *op)
+
+ Return the *__module__* attribute of the function object *op*. This is normally
+ a string containing the module name, but can be set to any other object by
+ Python code.
+
+
+.. cfunction:: PyObject* PyFunction_GetDefaults(PyObject *op)
+
+ Return the argument default values of the function object *op*. This can be a
+ tuple of arguments or *NULL*.
+
+
+.. cfunction:: int PyFunction_SetDefaults(PyObject *op, PyObject *defaults)
+
+ Set the argument default values for the function object *op*. *defaults* must be
+ *Py_None* or a tuple.
+
+ Raises :exc:`SystemError` and returns ``-1`` on failure.
+
+
+.. cfunction:: PyObject* PyFunction_GetClosure(PyObject *op)
+
+ Return the closure associated with the function object *op*. This can be *NULL*
+ or a tuple of cell objects.
+
+
+.. cfunction:: int PyFunction_SetClosure(PyObject *op, PyObject *closure)
+
+ Set the closure associated with the function object *op*. *closure* must be
+ *Py_None* or a tuple of cell objects.
+
+ Raises :exc:`SystemError` and returns ``-1`` on failure.
+
+
+.. _method-objects:
+
+Method Objects
+--------------
+
+.. index:: object: method
+
+There are some useful functions that are useful for working with method objects.
+
+
+.. cvar:: PyTypeObject PyMethod_Type
+
+ .. index:: single: MethodType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python method type. This
+ is exposed to Python programs as ``types.MethodType``.
+
+
+.. cfunction:: int PyMethod_Check(PyObject *o)
+
+ Return true if *o* is a method object (has type :cdata:`PyMethod_Type`). The
+ parameter must not be *NULL*.
+
+
+.. cfunction:: PyObject* PyMethod_New(PyObject *func, PyObject *self, PyObject *class)
+
+ Return a new method object, with *func* being any callable object; this is the
+ function that will be called when the method is called. If this method should
+ be bound to an instance, *self* should be the instance and *class* should be the
+ class of *self*, otherwise *self* should be *NULL* and *class* should be the
+ class which provides the unbound method..
+
+
+.. cfunction:: PyObject* PyMethod_Class(PyObject *meth)
+
+ Return the class object from which the method *meth* was created; if this was
+ created from an instance, it will be the class of the instance.
+
+
+.. cfunction:: PyObject* PyMethod_GET_CLASS(PyObject *meth)
+
+ Macro version of :cfunc:`PyMethod_Class` which avoids error checking.
+
+
+.. cfunction:: PyObject* PyMethod_Function(PyObject *meth)
+
+ Return the function object associated with the method *meth*.
+
+
+.. cfunction:: PyObject* PyMethod_GET_FUNCTION(PyObject *meth)
+
+ Macro version of :cfunc:`PyMethod_Function` which avoids error checking.
+
+
+.. cfunction:: PyObject* PyMethod_Self(PyObject *meth)
+
+ Return the instance associated with the method *meth* if it is bound, otherwise
+ return *NULL*.
+
+
+.. cfunction:: PyObject* PyMethod_GET_SELF(PyObject *meth)
+
+ Macro version of :cfunc:`PyMethod_Self` which avoids error checking.
+
+
+.. _moduleobjects:
+
+Module Objects
+--------------
+
+.. index:: object: module
+
+There are only a few functions special to module objects.
+
+
+.. cvar:: PyTypeObject PyModule_Type
+
+ .. index:: single: ModuleType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python module type. This
+ is exposed to Python programs as ``types.ModuleType``.
+
+
+.. cfunction:: int PyModule_Check(PyObject *p)
+
+ Return true if *p* is a module object, or a subtype of a module object.
+
+ .. versionchanged:: 2.2
+ Allowed subtypes to be accepted.
+
+
+.. cfunction:: int PyModule_CheckExact(PyObject *p)
+
+ Return true if *p* is a module object, but not a subtype of
+ :cdata:`PyModule_Type`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyModule_New(const char *name)
+
+ .. index::
+ single: __name__ (module attribute)
+ single: __doc__ (module attribute)
+ single: __file__ (module attribute)
+
+ Return a new module object with the :attr:`__name__` attribute set to *name*.
+ Only the module's :attr:`__doc__` and :attr:`__name__` attributes are filled in;
+ the caller is responsible for providing a :attr:`__file__` attribute.
+
+
+.. cfunction:: PyObject* PyModule_GetDict(PyObject *module)
+
+ .. index:: single: __dict__ (module attribute)
+
+ Return the dictionary object that implements *module*'s namespace; this object
+ is the same as the :attr:`__dict__` attribute of the module object. This
+ function never fails. It is recommended extensions use other
+ :cfunc:`PyModule_\*` and :cfunc:`PyObject_\*` functions rather than directly
+ manipulate a module's :attr:`__dict__`.
+
+
+.. cfunction:: char* PyModule_GetName(PyObject *module)
+
+ .. index::
+ single: __name__ (module attribute)
+ single: SystemError (built-in exception)
+
+ Return *module*'s :attr:`__name__` value. If the module does not provide one,
+ or if it is not a string, :exc:`SystemError` is raised and *NULL* is returned.
+
+
+.. cfunction:: char* PyModule_GetFilename(PyObject *module)
+
+ .. index::
+ single: __file__ (module attribute)
+ single: SystemError (built-in exception)
+
+ Return the name of the file from which *module* was loaded using *module*'s
+ :attr:`__file__` attribute. If this is not defined, or if it is not a string,
+ raise :exc:`SystemError` and return *NULL*.
+
+
+.. cfunction:: int PyModule_AddObject(PyObject *module, const char *name, PyObject *value)
+
+ Add an object to *module* as *name*. This is a convenience function which can
+ be used from the module's initialization function. This steals a reference to
+ *value*. Return ``-1`` on error, ``0`` on success.
+
+ .. versionadded:: 2.0
+
+
+.. cfunction:: int PyModule_AddIntConstant(PyObject *module, const char *name, long value)
+
+ Add an integer constant to *module* as *name*. This convenience function can be
+ used from the module's initialization function. Return ``-1`` on error, ``0`` on
+ success.
+
+ .. versionadded:: 2.0
+
+
+.. cfunction:: int PyModule_AddStringConstant(PyObject *module, const char *name, const char *value)
+
+ Add a string constant to *module* as *name*. This convenience function can be
+ used from the module's initialization function. The string *value* must be
+ null-terminated. Return ``-1`` on error, ``0`` on success.
+
+ .. versionadded:: 2.0
+
+
+.. _iterator-objects:
+
+Iterator Objects
+----------------
+
+Python provides two general-purpose iterator objects. The first, a sequence
+iterator, works with an arbitrary sequence supporting the :meth:`__getitem__`
+method. The second works with a callable object and a sentinel value, calling
+the callable for each item in the sequence, and ending the iteration when the
+sentinel value is returned.
+
+
+.. cvar:: PyTypeObject PySeqIter_Type
+
+ Type object for iterator objects returned by :cfunc:`PySeqIter_New` and the
+ one-argument form of the :func:`iter` built-in function for built-in sequence
+ types.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PySeqIter_Check(op)
+
+ Return true if the type of *op* is :cdata:`PySeqIter_Type`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PySeqIter_New(PyObject *seq)
+
+ Return an iterator that works with a general sequence object, *seq*. The
+ iteration ends when the sequence raises :exc:`IndexError` for the subscripting
+ operation.
+
+ .. versionadded:: 2.2
+
+
+.. cvar:: PyTypeObject PyCallIter_Type
+
+ Type object for iterator objects returned by :cfunc:`PyCallIter_New` and the
+ two-argument form of the :func:`iter` built-in function.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyCallIter_Check(op)
+
+ Return true if the type of *op* is :cdata:`PyCallIter_Type`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyCallIter_New(PyObject *callable, PyObject *sentinel)
+
+ Return a new iterator. The first parameter, *callable*, can be any Python
+ callable object that can be called with no parameters; each call to it should
+ return the next item in the iteration. When *callable* returns a value equal to
+ *sentinel*, the iteration will be terminated.
+
+ .. versionadded:: 2.2
+
+
+.. _descriptor-objects:
+
+Descriptor Objects
+------------------
+
+"Descriptors" are objects that describe some attribute of an object. They are
+found in the dictionary of type objects.
+
+
+.. cvar:: PyTypeObject PyProperty_Type
+
+ The type object for the built-in descriptor types.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyDescr_NewGetSet(PyTypeObject *type, struct PyGetSetDef *getset)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyDescr_NewMember(PyTypeObject *type, struct PyMemberDef *meth)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyDescr_NewMethod(PyTypeObject *type, struct PyMethodDef *meth)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyDescr_NewWrapper(PyTypeObject *type, struct wrapperbase *wrapper, void *wrapped)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyDescr_NewClassMethod(PyTypeObject *type, PyMethodDef *method)
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: int PyDescr_IsData(PyObject *descr)
+
+ Return true if the descriptor objects *descr* describes a data attribute, or
+ false if it describes a method. *descr* must be a descriptor object; there is
+ no error checking.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyWrapper_New(PyObject *, PyObject *)
+
+ .. versionadded:: 2.2
+
+
+.. _slice-objects:
+
+Slice Objects
+-------------
+
+
+.. cvar:: PyTypeObject PySlice_Type
+
+ .. index:: single: SliceType (in module types)
+
+ The type object for slice objects. This is the same as ``slice`` and
+ ``types.SliceType``.
+
+
+.. cfunction:: int PySlice_Check(PyObject *ob)
+
+ Return true if *ob* is a slice object; *ob* must not be *NULL*.
+
+
+.. cfunction:: PyObject* PySlice_New(PyObject *start, PyObject *stop, PyObject *step)
+
+ Return a new slice object with the given values. The *start*, *stop*, and
+ *step* parameters are used as the values of the slice object attributes of the
+ same names. Any of the values may be *NULL*, in which case the ``None`` will be
+ used for the corresponding attribute. Return *NULL* if the new object could not
+ be allocated.
+
+
+.. cfunction:: int PySlice_GetIndices(PySliceObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step)
+
+ Retrieve the start, stop and step indices from the slice object *slice*,
+ assuming a sequence of length *length*. Treats indices greater than *length* as
+ errors.
+
+ Returns 0 on success and -1 on error with no exception set (unless one of the
+ indices was not :const:`None` and failed to be converted to an integer, in which
+ case -1 is returned with an exception set).
+
+ You probably do not want to use this function. If you want to use slice objects
+ in versions of Python prior to 2.3, you would probably do well to incorporate
+ the source of :cfunc:`PySlice_GetIndicesEx`, suitably renamed, in the source of
+ your extension.
+
+
+.. cfunction:: int PySlice_GetIndicesEx(PySliceObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step, Py_ssize_t *slicelength)
+
+ Usable replacement for :cfunc:`PySlice_GetIndices`. Retrieve the start, stop,
+ and step indices from the slice object *slice* assuming a sequence of length
+ *length*, and store the length of the slice in *slicelength*. Out of bounds
+ indices are clipped in a manner consistent with the handling of normal slices.
+
+ Returns 0 on success and -1 on error with exception set.
+
+ .. versionadded:: 2.3
+
+
+.. _weakrefobjects:
+
+Weak Reference Objects
+----------------------
+
+Python supports *weak references* as first-class objects. There are two
+specific object types which directly implement weak references. The first is a
+simple reference object, and the second acts as a proxy for the original object
+as much as it can.
+
+
+.. cfunction:: int PyWeakref_Check(ob)
+
+ Return true if *ob* is either a reference or proxy object.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyWeakref_CheckRef(ob)
+
+ Return true if *ob* is a reference object.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: int PyWeakref_CheckProxy(ob)
+
+ Return true if *ob* is a proxy object.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyWeakref_NewRef(PyObject *ob, PyObject *callback)
+
+ Return a weak reference object for the object *ob*. This will always return
+ a new reference, but is not guaranteed to create a new object; an existing
+ reference object may be returned. The second parameter, *callback*, can be a
+ callable object that receives notification when *ob* is garbage collected; it
+ should accept a single parameter, which will be the weak reference object
+ itself. *callback* may also be ``None`` or *NULL*. If *ob* is not a
+ weakly-referencable object, or if *callback* is not callable, ``None``, or
+ *NULL*, this will return *NULL* and raise :exc:`TypeError`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyWeakref_NewProxy(PyObject *ob, PyObject *callback)
+
+ Return a weak reference proxy object for the object *ob*. This will always
+ return a new reference, but is not guaranteed to create a new object; an
+ existing proxy object may be returned. The second parameter, *callback*, can
+ be a callable object that receives notification when *ob* is garbage
+ collected; it should accept a single parameter, which will be the weak
+ reference object itself. *callback* may also be ``None`` or *NULL*. If *ob*
+ is not a weakly-referencable object, or if *callback* is not callable,
+ ``None``, or *NULL*, this will return *NULL* and raise :exc:`TypeError`.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyWeakref_GetObject(PyObject *ref)
+
+ Return the referenced object from a weak reference, *ref*. If the referent is
+ no longer live, returns ``None``.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* PyWeakref_GET_OBJECT(PyObject *ref)
+
+ Similar to :cfunc:`PyWeakref_GetObject`, but implemented as a macro that does no
+ error checking.
+
+ .. versionadded:: 2.2
+
+
+.. _cobjects:
+
+CObjects
+--------
+
+.. index:: object: CObject
+
+Refer to *Extending and Embedding the Python Interpreter*, section 1.12,
+"Providing a C API for an Extension Module," for more information on using these
+objects.
+
+
+.. ctype:: PyCObject
+
+ This subtype of :ctype:`PyObject` represents an opaque value, useful for C
+ extension modules who need to pass an opaque value (as a :ctype:`void\*`
+ pointer) through Python code to other C code. It is often used to make a C
+ function pointer defined in one module available to other modules, so the
+ regular import mechanism can be used to access C APIs defined in dynamically
+ loaded modules.
+
+
+.. cfunction:: int PyCObject_Check(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyCObject`.
+
+
+.. cfunction:: PyObject* PyCObject_FromVoidPtr(void* cobj, void (*destr)(void *))
+
+ Create a :ctype:`PyCObject` from the ``void *`` *cobj*. The *destr* function
+ will be called when the object is reclaimed, unless it is *NULL*.
+
+
+.. cfunction:: PyObject* PyCObject_FromVoidPtrAndDesc(void* cobj, void* desc, void (*destr)(void *, void *))
+
+ Create a :ctype:`PyCObject` from the :ctype:`void \*` *cobj*. The *destr*
+ function will be called when the object is reclaimed. The *desc* argument can
+ be used to pass extra callback data for the destructor function.
+
+
+.. cfunction:: void* PyCObject_AsVoidPtr(PyObject* self)
+
+ Return the object :ctype:`void \*` that the :ctype:`PyCObject` *self* was
+ created with.
+
+
+.. cfunction:: void* PyCObject_GetDesc(PyObject* self)
+
+ Return the description :ctype:`void \*` that the :ctype:`PyCObject` *self* was
+ created with.
+
+
+.. cfunction:: int PyCObject_SetVoidPtr(PyObject* self, void* cobj)
+
+ Set the void pointer inside *self* to *cobj*. The :ctype:`PyCObject` must not
+ have an associated destructor. Return true on success, false on failure.
+
+
+.. _cell-objects:
+
+Cell Objects
+------------
+
+"Cell" objects are used to implement variables referenced by multiple scopes.
+For each such variable, a cell object is created to store the value; the local
+variables of each stack frame that references the value contains a reference to
+the cells from outer scopes which also use that variable. When the value is
+accessed, the value contained in the cell is used instead of the cell object
+itself. This de-referencing of the cell object requires support from the
+generated byte-code; these are not automatically de-referenced when accessed.
+Cell objects are not likely to be useful elsewhere.
+
+
+.. ctype:: PyCellObject
+
+ The C structure used for cell objects.
+
+
+.. cvar:: PyTypeObject PyCell_Type
+
+ The type object corresponding to cell objects.
+
+
+.. cfunction:: int PyCell_Check(ob)
+
+ Return true if *ob* is a cell object; *ob* must not be *NULL*.
+
+
+.. cfunction:: PyObject* PyCell_New(PyObject *ob)
+
+ Create and return a new cell object containing the value *ob*. The parameter may
+ be *NULL*.
+
+
+.. cfunction:: PyObject* PyCell_Get(PyObject *cell)
+
+ Return the contents of the cell *cell*.
+
+
+.. cfunction:: PyObject* PyCell_GET(PyObject *cell)
+
+ Return the contents of the cell *cell*, but without checking that *cell* is
+ non-*NULL* and a cell object.
+
+
+.. cfunction:: int PyCell_Set(PyObject *cell, PyObject *value)
+
+ Set the contents of the cell object *cell* to *value*. This releases the
+ reference to any current content of the cell. *value* may be *NULL*. *cell*
+ must be non-*NULL*; if it is not a cell object, ``-1`` will be returned. On
+ success, ``0`` will be returned.
+
+
+.. cfunction:: void PyCell_SET(PyObject *cell, PyObject *value)
+
+ Sets the value of the cell object *cell* to *value*. No reference counts are
+ adjusted, and no checks are made for safety; *cell* must be non-*NULL* and must
+ be a cell object.
+
+
+.. _gen-objects:
+
+Generator Objects
+-----------------
+
+Generator objects are what Python uses to implement generator iterators. They
+are normally created by iterating over a function that yields values, rather
+than explicitly calling :cfunc:`PyGen_New`.
+
+
+.. ctype:: PyGenObject
+
+ The C structure used for generator objects.
+
+
+.. cvar:: PyTypeObject PyGen_Type
+
+ The type object corresponding to generator objects
+
+
+.. cfunction:: int PyGen_Check(ob)
+
+ Return true if *ob* is a generator object; *ob* must not be *NULL*.
+
+
+.. cfunction:: int PyGen_CheckExact(ob)
+
+ Return true if *ob*'s type is *PyGen_Type* is a generator object; *ob* must not
+ be *NULL*.
+
+
+.. cfunction:: PyObject* PyGen_New(PyFrameObject *frame)
+
+ Create and return a new generator object based on the *frame* object. A
+ reference to *frame* is stolen by this function. The parameter must not be
+ *NULL*.
+
+
+.. _datetimeobjects:
+
+DateTime Objects
+----------------
+
+Various date and time objects are supplied by the :mod:`datetime` module.
+Before using any of these functions, the header file :file:`datetime.h` must be
+included in your source (note that this is not included by :file:`Python.h`),
+and the macro :cfunc:`PyDateTime_IMPORT` must be invoked. The macro puts a
+pointer to a C structure into a static variable, ``PyDateTimeAPI``, that is
+used by the following macros.
+
+Type-check macros:
+
+
+.. cfunction:: int PyDate_Check(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_DateType` or a subtype of
+ :cdata:`PyDateTime_DateType`. *ob* must not be *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDate_CheckExact(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_DateType`. *ob* must not be
+ *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_Check(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_DateTimeType` or a subtype of
+ :cdata:`PyDateTime_DateTimeType`. *ob* must not be *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_CheckExact(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_DateTimeType`. *ob* must not
+ be *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyTime_Check(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_TimeType` or a subtype of
+ :cdata:`PyDateTime_TimeType`. *ob* must not be *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyTime_CheckExact(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_TimeType`. *ob* must not be
+ *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDelta_Check(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_DeltaType` or a subtype of
+ :cdata:`PyDateTime_DeltaType`. *ob* must not be *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDelta_CheckExact(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_DeltaType`. *ob* must not be
+ *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyTZInfo_Check(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_TZInfoType` or a subtype of
+ :cdata:`PyDateTime_TZInfoType`. *ob* must not be *NULL*.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyTZInfo_CheckExact(PyObject *ob)
+
+ Return true if *ob* is of type :cdata:`PyDateTime_TZInfoType`. *ob* must not be
+ *NULL*.
+
+ .. versionadded:: 2.4
+
+Macros to create objects:
+
+
+.. cfunction:: PyObject* PyDate_FromDate(int year, int month, int day)
+
+ Return a ``datetime.date`` object with the specified year, month and day.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyDateTime_FromDateAndTime(int year, int month, int day, int hour, int minute, int second, int usecond)
+
+ Return a ``datetime.datetime`` object with the specified year, month, day, hour,
+ minute, second and microsecond.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyTime_FromTime(int hour, int minute, int second, int usecond)
+
+ Return a ``datetime.time`` object with the specified hour, minute, second and
+ microsecond.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyDelta_FromDSU(int days, int seconds, int useconds)
+
+ Return a ``datetime.timedelta`` object representing the given number of days,
+ seconds and microseconds. Normalization is performed so that the resulting
+ number of microseconds and seconds lie in the ranges documented for
+ ``datetime.timedelta`` objects.
+
+ .. versionadded:: 2.4
+
+Macros to extract fields from date objects. The argument must be an instance of
+:cdata:`PyDateTime_Date`, including subclasses (such as
+:cdata:`PyDateTime_DateTime`). The argument must not be *NULL*, and the type is
+not checked:
+
+
+.. cfunction:: int PyDateTime_GET_YEAR(PyDateTime_Date *o)
+
+ Return the year, as a positive int.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_GET_MONTH(PyDateTime_Date *o)
+
+ Return the month, as an int from 1 through 12.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_GET_DAY(PyDateTime_Date *o)
+
+ Return the day, as an int from 1 through 31.
+
+ .. versionadded:: 2.4
+
+Macros to extract fields from datetime objects. The argument must be an
+instance of :cdata:`PyDateTime_DateTime`, including subclasses. The argument
+must not be *NULL*, and the type is not checked:
+
+
+.. cfunction:: int PyDateTime_DATE_GET_HOUR(PyDateTime_DateTime *o)
+
+ Return the hour, as an int from 0 through 23.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_DATE_GET_MINUTE(PyDateTime_DateTime *o)
+
+ Return the minute, as an int from 0 through 59.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_DATE_GET_SECOND(PyDateTime_DateTime *o)
+
+ Return the second, as an int from 0 through 59.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_DATE_GET_MICROSECOND(PyDateTime_DateTime *o)
+
+ Return the microsecond, as an int from 0 through 999999.
+
+ .. versionadded:: 2.4
+
+Macros to extract fields from time objects. The argument must be an instance of
+:cdata:`PyDateTime_Time`, including subclasses. The argument must not be *NULL*,
+and the type is not checked:
+
+
+.. cfunction:: int PyDateTime_TIME_GET_HOUR(PyDateTime_Time *o)
+
+ Return the hour, as an int from 0 through 23.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_TIME_GET_MINUTE(PyDateTime_Time *o)
+
+ Return the minute, as an int from 0 through 59.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_TIME_GET_SECOND(PyDateTime_Time *o)
+
+ Return the second, as an int from 0 through 59.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int PyDateTime_TIME_GET_MICROSECOND(PyDateTime_Time *o)
+
+ Return the microsecond, as an int from 0 through 999999.
+
+ .. versionadded:: 2.4
+
+Macros for the convenience of modules implementing the DB API:
+
+
+.. cfunction:: PyObject* PyDateTime_FromTimestamp(PyObject *args)
+
+ Create and return a new ``datetime.datetime`` object given an argument tuple
+ suitable for passing to ``datetime.datetime.fromtimestamp()``.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* PyDate_FromTimestamp(PyObject *args)
+
+ Create and return a new ``datetime.date`` object given an argument tuple
+ suitable for passing to ``datetime.date.fromtimestamp()``.
+
+ .. versionadded:: 2.4
+
+
+.. _setobjects:
+
+Set Objects
+-----------
+
+.. sectionauthor:: Raymond D. Hettinger <python@rcn.com>
+
+
+.. index::
+ object: set
+ object: frozenset
+
+.. versionadded:: 2.5
+
+This section details the public API for :class:`set` and :class:`frozenset`
+objects. Any functionality not listed below is best accessed using the either
+the abstract object protocol (including :cfunc:`PyObject_CallMethod`,
+:cfunc:`PyObject_RichCompareBool`, :cfunc:`PyObject_Hash`,
+:cfunc:`PyObject_Repr`, :cfunc:`PyObject_IsTrue`, :cfunc:`PyObject_Print`, and
+:cfunc:`PyObject_GetIter`) or the abstract number protocol (including
+:cfunc:`PyNumber_And`, :cfunc:`PyNumber_Subtract`, :cfunc:`PyNumber_Or`,
+:cfunc:`PyNumber_Xor`, :cfunc:`PyNumber_InPlaceAnd`,
+:cfunc:`PyNumber_InPlaceSubtract`, :cfunc:`PyNumber_InPlaceOr`, and
+:cfunc:`PyNumber_InPlaceXor`).
+
+
+.. ctype:: PySetObject
+
+ This subtype of :ctype:`PyObject` is used to hold the internal data for both
+ :class:`set` and :class:`frozenset` objects. It is like a :ctype:`PyDictObject`
+ in that it is a fixed size for small sets (much like tuple storage) and will
+ point to a separate, variable sized block of memory for medium and large sized
+ sets (much like list storage). None of the fields of this structure should be
+ considered public and are subject to change. All access should be done through
+ the documented API rather than by manipulating the values in the structure.
+
+
+.. cvar:: PyTypeObject PySet_Type
+
+ This is an instance of :ctype:`PyTypeObject` representing the Python
+ :class:`set` type.
+
+
+.. cvar:: PyTypeObject PyFrozenSet_Type
+
+ This is an instance of :ctype:`PyTypeObject` representing the Python
+ :class:`frozenset` type.
+
+The following type check macros work on pointers to any Python object. Likewise,
+the constructor functions work with any iterable Python object.
+
+
+.. cfunction:: int PyAnySet_Check(PyObject *p)
+
+ Return true if *p* is a :class:`set` object, a :class:`frozenset` object, or an
+ instance of a subtype.
+
+
+.. cfunction:: int PyAnySet_CheckExact(PyObject *p)
+
+ Return true if *p* is a :class:`set` object or a :class:`frozenset` object but
+ not an instance of a subtype.
+
+
+.. cfunction:: int PyFrozenSet_CheckExact(PyObject *p)
+
+ Return true if *p* is a :class:`frozenset` object but not an instance of a
+ subtype.
+
+
+.. cfunction:: PyObject* PySet_New(PyObject *iterable)
+
+ Return a new :class:`set` containing objects returned by the *iterable*. The
+ *iterable* may be *NULL* to create a new empty set. Return the new set on
+ success or *NULL* on failure. Raise :exc:`TypeError` if *iterable* is not
+ actually iterable. The constructor is also useful for copying a set
+ (``c=set(s)``).
+
+
+.. cfunction:: PyObject* PyFrozenSet_New(PyObject *iterable)
+
+ Return a new :class:`frozenset` containing objects returned by the *iterable*.
+ The *iterable* may be *NULL* to create a new empty frozenset. Return the new
+ set on success or *NULL* on failure. Raise :exc:`TypeError` if *iterable* is
+ not actually iterable.
+
+The following functions and macros are available for instances of :class:`set`
+or :class:`frozenset` or instances of their subtypes.
+
+
+.. cfunction:: int PySet_Size(PyObject *anyset)
+
+ .. index:: builtin: len
+
+ Return the length of a :class:`set` or :class:`frozenset` object. Equivalent to
+ ``len(anyset)``. Raises a :exc:`PyExc_SystemError` if *anyset* is not a
+ :class:`set`, :class:`frozenset`, or an instance of a subtype.
+
+
+.. cfunction:: int PySet_GET_SIZE(PyObject *anyset)
+
+ Macro form of :cfunc:`PySet_Size` without error checking.
+
+
+.. cfunction:: int PySet_Contains(PyObject *anyset, PyObject *key)
+
+ Return 1 if found, 0 if not found, and -1 if an error is encountered. Unlike
+ the Python :meth:`__contains__` method, this function does not automatically
+ convert unhashable sets into temporary frozensets. Raise a :exc:`TypeError` if
+ the *key* is unhashable. Raise :exc:`PyExc_SystemError` if *anyset* is not a
+ :class:`set`, :class:`frozenset`, or an instance of a subtype.
+
+The following functions are available for instances of :class:`set` or its
+subtypes but not for instances of :class:`frozenset` or its subtypes.
+
+
+.. cfunction:: int PySet_Add(PyObject *set, PyObject *key)
+
+ Add *key* to a :class:`set` instance. Does not apply to :class:`frozenset`
+ instances. Return 0 on success or -1 on failure. Raise a :exc:`TypeError` if
+ the *key* is unhashable. Raise a :exc:`MemoryError` if there is no room to grow.
+ Raise a :exc:`SystemError` if *set* is an not an instance of :class:`set` or its
+ subtype.
+
+
+.. cfunction:: int PySet_Discard(PyObject *set, PyObject *key)
+
+ Return 1 if found and removed, 0 if not found (no action taken), and -1 if an
+ error is encountered. Does not raise :exc:`KeyError` for missing keys. Raise a
+ :exc:`TypeError` if the *key* is unhashable. Unlike the Python :meth:`discard`
+ method, this function does not automatically convert unhashable sets into
+ temporary frozensets. Raise :exc:`PyExc_SystemError` if *set* is an not an
+ instance of :class:`set` or its subtype.
+
+
+.. cfunction:: PyObject* PySet_Pop(PyObject *set)
+
+ Return a new reference to an arbitrary object in the *set*, and removes the
+ object from the *set*. Return *NULL* on failure. Raise :exc:`KeyError` if the
+ set is empty. Raise a :exc:`SystemError` if *set* is an not an instance of
+ :class:`set` or its subtype.
+
+
+.. cfunction:: int PySet_Clear(PyObject *set)
+
+ Empty an existing set of all elements.
+
diff --git a/Doc/c-api/exceptions.rst b/Doc/c-api/exceptions.rst
new file mode 100644
index 0000000000..68ac090f99
--- /dev/null
+++ b/Doc/c-api/exceptions.rst
@@ -0,0 +1,515 @@
+.. highlightlang:: c
+
+
+.. _exceptionhandling:
+
+******************
+Exception Handling
+******************
+
+The functions described in this chapter will let you handle and raise Python
+exceptions. It is important to understand some of the basics of Python
+exception handling. It works somewhat like the Unix :cdata:`errno` variable:
+there is a global indicator (per thread) of the last error that occurred. Most
+functions don't clear this on success, but will set it to indicate the cause of
+the error on failure. Most functions also return an error indicator, usually
+*NULL* if they are supposed to return a pointer, or ``-1`` if they return an
+integer (exception: the :cfunc:`PyArg_\*` functions return ``1`` for success and
+``0`` for failure).
+
+When a function must fail because some function it called failed, it generally
+doesn't set the error indicator; the function it called already set it. It is
+responsible for either handling the error and clearing the exception or
+returning after cleaning up any resources it holds (such as object references or
+memory allocations); it should *not* continue normally if it is not prepared to
+handle the error. If returning due to an error, it is important to indicate to
+the caller that an error has been set. If the error is not handled or carefully
+propagated, additional calls into the Python/C API may not behave as intended
+and may fail in mysterious ways.
+
+The error indicator consists of three Python objects corresponding to the result
+of ``sys.exc_info()``. API functions exist to interact with the error indicator
+in various ways. There is a separate error indicator for each thread.
+
+.. % XXX Order of these should be more thoughtful.
+.. % Either alphabetical or some kind of structure.
+
+
+.. cfunction:: void PyErr_Print()
+
+ Print a standard traceback to ``sys.stderr`` and clear the error indicator.
+ Call this function only when the error indicator is set. (Otherwise it will
+ cause a fatal error!)
+
+
+.. cfunction:: PyObject* PyErr_Occurred()
+
+ Test whether the error indicator is set. If set, return the exception *type*
+ (the first argument to the last call to one of the :cfunc:`PyErr_Set\*`
+ functions or to :cfunc:`PyErr_Restore`). If not set, return *NULL*. You do not
+ own a reference to the return value, so you do not need to :cfunc:`Py_DECREF`
+ it.
+
+ .. note::
+
+ Do not compare the return value to a specific exception; use
+ :cfunc:`PyErr_ExceptionMatches` instead, shown below. (The comparison could
+ easily fail since the exception may be an instance instead of a class, in the
+ case of a class exception, or it may the a subclass of the expected exception.)
+
+
+.. cfunction:: int PyErr_ExceptionMatches(PyObject *exc)
+
+ Equivalent to ``PyErr_GivenExceptionMatches(PyErr_Occurred(), exc)``. This
+ should only be called when an exception is actually set; a memory access
+ violation will occur if no exception has been raised.
+
+
+.. cfunction:: int PyErr_GivenExceptionMatches(PyObject *given, PyObject *exc)
+
+ Return true if the *given* exception matches the exception in *exc*. If *exc*
+ is a class object, this also returns true when *given* is an instance of a
+ subclass. If *exc* is a tuple, all exceptions in the tuple (and recursively in
+ subtuples) are searched for a match. If *given* is *NULL*, a memory access
+ violation will occur.
+
+
+.. cfunction:: void PyErr_NormalizeException(PyObject**exc, PyObject**val, PyObject**tb)
+
+ Under certain circumstances, the values returned by :cfunc:`PyErr_Fetch` below
+ can be "unnormalized", meaning that ``*exc`` is a class object but ``*val`` is
+ not an instance of the same class. This function can be used to instantiate
+ the class in that case. If the values are already normalized, nothing happens.
+ The delayed normalization is implemented to improve performance.
+
+
+.. cfunction:: void PyErr_Clear()
+
+ Clear the error indicator. If the error indicator is not set, there is no
+ effect.
+
+
+.. cfunction:: void PyErr_Fetch(PyObject **ptype, PyObject **pvalue, PyObject **ptraceback)
+
+ Retrieve the error indicator into three variables whose addresses are passed.
+ If the error indicator is not set, set all three variables to *NULL*. If it is
+ set, it will be cleared and you own a reference to each object retrieved. The
+ value and traceback object may be *NULL* even when the type object is not.
+
+ .. note::
+
+ This function is normally only used by code that needs to handle exceptions or
+ by code that needs to save and restore the error indicator temporarily.
+
+
+.. cfunction:: void PyErr_Restore(PyObject *type, PyObject *value, PyObject *traceback)
+
+ Set the error indicator from the three objects. If the error indicator is
+ already set, it is cleared first. If the objects are *NULL*, the error
+ indicator is cleared. Do not pass a *NULL* type and non-*NULL* value or
+ traceback. The exception type should be a class. Do not pass an invalid
+ exception type or value. (Violating these rules will cause subtle problems
+ later.) This call takes away a reference to each object: you must own a
+ reference to each object before the call and after the call you no longer own
+ these references. (If you don't understand this, don't use this function. I
+ warned you.)
+
+ .. note::
+
+ This function is normally only used by code that needs to save and restore the
+ error indicator temporarily; use :cfunc:`PyErr_Fetch` to save the current
+ exception state.
+
+
+.. cfunction:: void PyErr_SetString(PyObject *type, const char *message)
+
+ This is the most common way to set the error indicator. The first argument
+ specifies the exception type; it is normally one of the standard exceptions,
+ e.g. :cdata:`PyExc_RuntimeError`. You need not increment its reference count.
+ The second argument is an error message; it is converted to a string object.
+
+
+.. cfunction:: void PyErr_SetObject(PyObject *type, PyObject *value)
+
+ This function is similar to :cfunc:`PyErr_SetString` but lets you specify an
+ arbitrary Python object for the "value" of the exception.
+
+
+.. cfunction:: PyObject* PyErr_Format(PyObject *exception, const char *format, ...)
+
+ This function sets the error indicator and returns *NULL*. *exception* should be
+ a Python exception (class, not an instance). *format* should be a string,
+ containing format codes, similar to :cfunc:`printf`. The ``width.precision``
+ before a format code is parsed, but the width part is ignored.
+
+ .. % This should be exactly the same as the table in PyString_FromFormat.
+ .. % One should just refer to the other.
+ .. % The descriptions for %zd and %zu are wrong, but the truth is complicated
+ .. % because not all compilers support the %z width modifier -- we fake it
+ .. % when necessary via interpolating PY_FORMAT_SIZE_T.
+ .. % %u, %lu, %zu should have "new in Python 2.5" blurbs.
+
+ +-------------------+---------------+--------------------------------+
+ | Format Characters | Type | Comment |
+ +===================+===============+================================+
+ | :attr:`%%` | *n/a* | The literal % character. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%c` | int | A single character, |
+ | | | represented as an C int. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%d` | int | Exactly equivalent to |
+ | | | ``printf("%d")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%u` | unsigned int | Exactly equivalent to |
+ | | | ``printf("%u")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%ld` | long | Exactly equivalent to |
+ | | | ``printf("%ld")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%lu` | unsigned long | Exactly equivalent to |
+ | | | ``printf("%lu")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%zd` | Py_ssize_t | Exactly equivalent to |
+ | | | ``printf("%zd")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%zu` | size_t | Exactly equivalent to |
+ | | | ``printf("%zu")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%i` | int | Exactly equivalent to |
+ | | | ``printf("%i")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%x` | int | Exactly equivalent to |
+ | | | ``printf("%x")``. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%s` | char\* | A null-terminated C character |
+ | | | array. |
+ +-------------------+---------------+--------------------------------+
+ | :attr:`%p` | void\* | The hex representation of a C |
+ | | | pointer. Mostly equivalent to |
+ | | | ``printf("%p")`` except that |
+ | | | it is guaranteed to start with |
+ | | | the literal ``0x`` regardless |
+ | | | of what the platform's |
+ | | | ``printf`` yields. |
+ +-------------------+---------------+--------------------------------+
+
+ An unrecognized format character causes all the rest of the format string to be
+ copied as-is to the result string, and any extra arguments discarded.
+
+
+.. cfunction:: void PyErr_SetNone(PyObject *type)
+
+ This is a shorthand for ``PyErr_SetObject(type, Py_None)``.
+
+
+.. cfunction:: int PyErr_BadArgument()
+
+ This is a shorthand for ``PyErr_SetString(PyExc_TypeError, message)``, where
+ *message* indicates that a built-in operation was invoked with an illegal
+ argument. It is mostly for internal use.
+
+
+.. cfunction:: PyObject* PyErr_NoMemory()
+
+ This is a shorthand for ``PyErr_SetNone(PyExc_MemoryError)``; it returns *NULL*
+ so an object allocation function can write ``return PyErr_NoMemory();`` when it
+ runs out of memory.
+
+
+.. cfunction:: PyObject* PyErr_SetFromErrno(PyObject *type)
+
+ .. index:: single: strerror()
+
+ This is a convenience function to raise an exception when a C library function
+ has returned an error and set the C variable :cdata:`errno`. It constructs a
+ tuple object whose first item is the integer :cdata:`errno` value and whose
+ second item is the corresponding error message (gotten from :cfunc:`strerror`),
+ and then calls ``PyErr_SetObject(type, object)``. On Unix, when the
+ :cdata:`errno` value is :const:`EINTR`, indicating an interrupted system call,
+ this calls :cfunc:`PyErr_CheckSignals`, and if that set the error indicator,
+ leaves it set to that. The function always returns *NULL*, so a wrapper
+ function around a system call can write ``return PyErr_SetFromErrno(type);``
+ when the system call returns an error.
+
+
+.. cfunction:: PyObject* PyErr_SetFromErrnoWithFilename(PyObject *type, const char *filename)
+
+ Similar to :cfunc:`PyErr_SetFromErrno`, with the additional behavior that if
+ *filename* is not *NULL*, it is passed to the constructor of *type* as a third
+ parameter. In the case of exceptions such as :exc:`IOError` and :exc:`OSError`,
+ this is used to define the :attr:`filename` attribute of the exception instance.
+
+
+.. cfunction:: PyObject* PyErr_SetFromWindowsErr(int ierr)
+
+ This is a convenience function to raise :exc:`WindowsError`. If called with
+ *ierr* of :cdata:`0`, the error code returned by a call to :cfunc:`GetLastError`
+ is used instead. It calls the Win32 function :cfunc:`FormatMessage` to retrieve
+ the Windows description of error code given by *ierr* or :cfunc:`GetLastError`,
+ then it constructs a tuple object whose first item is the *ierr* value and whose
+ second item is the corresponding error message (gotten from
+ :cfunc:`FormatMessage`), and then calls ``PyErr_SetObject(PyExc_WindowsError,
+ object)``. This function always returns *NULL*. Availability: Windows.
+
+
+.. cfunction:: PyObject* PyErr_SetExcFromWindowsErr(PyObject *type, int ierr)
+
+ Similar to :cfunc:`PyErr_SetFromWindowsErr`, with an additional parameter
+ specifying the exception type to be raised. Availability: Windows.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: PyObject* PyErr_SetFromWindowsErrWithFilename(int ierr, const char *filename)
+
+ Similar to :cfunc:`PyErr_SetFromWindowsErr`, with the additional behavior that
+ if *filename* is not *NULL*, it is passed to the constructor of
+ :exc:`WindowsError` as a third parameter. Availability: Windows.
+
+
+.. cfunction:: PyObject* PyErr_SetExcFromWindowsErrWithFilename(PyObject *type, int ierr, char *filename)
+
+ Similar to :cfunc:`PyErr_SetFromWindowsErrWithFilename`, with an additional
+ parameter specifying the exception type to be raised. Availability: Windows.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: void PyErr_BadInternalCall()
+
+ This is a shorthand for ``PyErr_SetString(PyExc_TypeError, message)``, where
+ *message* indicates that an internal operation (e.g. a Python/C API function)
+ was invoked with an illegal argument. It is mostly for internal use.
+
+
+.. cfunction:: int PyErr_WarnEx(PyObject *category, char *message, int stacklevel)
+
+ Issue a warning message. The *category* argument is a warning category (see
+ below) or *NULL*; the *message* argument is a message string. *stacklevel* is a
+ positive number giving a number of stack frames; the warning will be issued from
+ the currently executing line of code in that stack frame. A *stacklevel* of 1
+ is the function calling :cfunc:`PyErr_WarnEx`, 2 is the function above that,
+ and so forth.
+
+ This function normally prints a warning message to *sys.stderr*; however, it is
+ also possible that the user has specified that warnings are to be turned into
+ errors, and in that case this will raise an exception. It is also possible that
+ the function raises an exception because of a problem with the warning machinery
+ (the implementation imports the :mod:`warnings` module to do the heavy lifting).
+ The return value is ``0`` if no exception is raised, or ``-1`` if an exception
+ is raised. (It is not possible to determine whether a warning message is
+ actually printed, nor what the reason is for the exception; this is
+ intentional.) If an exception is raised, the caller should do its normal
+ exception handling (for example, :cfunc:`Py_DECREF` owned references and return
+ an error value).
+
+ Warning categories must be subclasses of :cdata:`Warning`; the default warning
+ category is :cdata:`RuntimeWarning`. The standard Python warning categories are
+ available as global variables whose names are ``PyExc_`` followed by the Python
+ exception name. These have the type :ctype:`PyObject\*`; they are all class
+ objects. Their names are :cdata:`PyExc_Warning`, :cdata:`PyExc_UserWarning`,
+ :cdata:`PyExc_UnicodeWarning`, :cdata:`PyExc_DeprecationWarning`,
+ :cdata:`PyExc_SyntaxWarning`, :cdata:`PyExc_RuntimeWarning`, and
+ :cdata:`PyExc_FutureWarning`. :cdata:`PyExc_Warning` is a subclass of
+ :cdata:`PyExc_Exception`; the other warning categories are subclasses of
+ :cdata:`PyExc_Warning`.
+
+ For information about warning control, see the documentation for the
+ :mod:`warnings` module and the :option:`-W` option in the command line
+ documentation. There is no C API for warning control.
+
+
+.. cfunction:: int PyErr_WarnExplicit(PyObject *category, const char *message, const char *filename, int lineno, const char *module, PyObject *registry)
+
+ Issue a warning message with explicit control over all warning attributes. This
+ is a straightforward wrapper around the Python function
+ :func:`warnings.warn_explicit`, see there for more information. The *module*
+ and *registry* arguments may be set to *NULL* to get the default effect
+ described there.
+
+
+.. cfunction:: int PyErr_CheckSignals()
+
+ .. index::
+ module: signal
+ single: SIGINT
+ single: KeyboardInterrupt (built-in exception)
+
+ This function interacts with Python's signal handling. It checks whether a
+ signal has been sent to the processes and if so, invokes the corresponding
+ signal handler. If the :mod:`signal` module is supported, this can invoke a
+ signal handler written in Python. In all cases, the default effect for
+ :const:`SIGINT` is to raise the :exc:`KeyboardInterrupt` exception. If an
+ exception is raised the error indicator is set and the function returns ``-1``;
+ otherwise the function returns ``0``. The error indicator may or may not be
+ cleared if it was previously set.
+
+
+.. cfunction:: void PyErr_SetInterrupt()
+
+ .. index::
+ single: SIGINT
+ single: KeyboardInterrupt (built-in exception)
+
+ This function simulates the effect of a :const:`SIGINT` signal arriving --- the
+ next time :cfunc:`PyErr_CheckSignals` is called, :exc:`KeyboardInterrupt` will
+ be raised. It may be called without holding the interpreter lock.
+
+ .. % XXX This was described as obsolete, but is used in
+ .. % thread.interrupt_main() (used from IDLE), so it's still needed.
+
+
+.. cfunction:: PyObject* PyErr_NewException(char *name, PyObject *base, PyObject *dict)
+
+ This utility function creates and returns a new exception object. The *name*
+ argument must be the name of the new exception, a C string of the form
+ ``module.class``. The *base* and *dict* arguments are normally *NULL*. This
+ creates a class object derived from :exc:`Exception` (accessible in C as
+ :cdata:`PyExc_Exception`).
+
+ The :attr:`__module__` attribute of the new class is set to the first part (up
+ to the last dot) of the *name* argument, and the class name is set to the last
+ part (after the last dot). The *base* argument can be used to specify alternate
+ base classes; it can either be only one class or a tuple of classes. The *dict*
+ argument can be used to specify a dictionary of class variables and methods.
+
+
+.. cfunction:: void PyErr_WriteUnraisable(PyObject *obj)
+
+ This utility function prints a warning message to ``sys.stderr`` when an
+ exception has been set but it is impossible for the interpreter to actually
+ raise the exception. It is used, for example, when an exception occurs in an
+ :meth:`__del__` method.
+
+ The function is called with a single argument *obj* that identifies the context
+ in which the unraisable exception occurred. The repr of *obj* will be printed in
+ the warning message.
+
+
+.. _standardexceptions:
+
+Standard Exceptions
+===================
+
+All standard Python exceptions are available as global variables whose names are
+``PyExc_`` followed by the Python exception name. These have the type
+:ctype:`PyObject\*`; they are all class objects. For completeness, here are all
+the variables:
+
++------------------------------------+----------------------------+----------+
+| C Name | Python Name | Notes |
++====================================+============================+==========+
+| :cdata:`PyExc_BaseException` | :exc:`BaseException` | (1), (4) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_Exception` | :exc:`Exception` | \(1) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_ArithmeticError` | :exc:`ArithmeticError` | \(1) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_LookupError` | :exc:`LookupError` | \(1) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_AssertionError` | :exc:`AssertionError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_AttributeError` | :exc:`AttributeError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_EOFError` | :exc:`EOFError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_EnvironmentError` | :exc:`EnvironmentError` | \(1) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_FloatingPointError` | :exc:`FloatingPointError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_IOError` | :exc:`IOError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_ImportError` | :exc:`ImportError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_IndexError` | :exc:`IndexError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_KeyError` | :exc:`KeyError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_KeyboardInterrupt` | :exc:`KeyboardInterrupt` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_MemoryError` | :exc:`MemoryError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_NameError` | :exc:`NameError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_NotImplementedError` | :exc:`NotImplementedError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_OSError` | :exc:`OSError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_OverflowError` | :exc:`OverflowError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_ReferenceError` | :exc:`ReferenceError` | \(2) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_RuntimeError` | :exc:`RuntimeError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_SyntaxError` | :exc:`SyntaxError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_SystemError` | :exc:`SystemError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_SystemExit` | :exc:`SystemExit` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_TypeError` | :exc:`TypeError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_ValueError` | :exc:`ValueError` | |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_WindowsError` | :exc:`WindowsError` | \(3) |
++------------------------------------+----------------------------+----------+
+| :cdata:`PyExc_ZeroDivisionError` | :exc:`ZeroDivisionError` | |
++------------------------------------+----------------------------+----------+
+
+.. index::
+ single: PyExc_BaseException
+ single: PyExc_Exception
+ single: PyExc_ArithmeticError
+ single: PyExc_LookupError
+ single: PyExc_AssertionError
+ single: PyExc_AttributeError
+ single: PyExc_EOFError
+ single: PyExc_EnvironmentError
+ single: PyExc_FloatingPointError
+ single: PyExc_IOError
+ single: PyExc_ImportError
+ single: PyExc_IndexError
+ single: PyExc_KeyError
+ single: PyExc_KeyboardInterrupt
+ single: PyExc_MemoryError
+ single: PyExc_NameError
+ single: PyExc_NotImplementedError
+ single: PyExc_OSError
+ single: PyExc_OverflowError
+ single: PyExc_ReferenceError
+ single: PyExc_RuntimeError
+ single: PyExc_SyntaxError
+ single: PyExc_SystemError
+ single: PyExc_SystemExit
+ single: PyExc_TypeError
+ single: PyExc_ValueError
+ single: PyExc_WindowsError
+ single: PyExc_ZeroDivisionError
+
+Notes:
+
+(1)
+ This is a base class for other standard exceptions.
+
+(2)
+ This is the same as :exc:`weakref.ReferenceError`.
+
+(3)
+ Only defined on Windows; protect code that uses this by testing that the
+ preprocessor macro ``MS_WINDOWS`` is defined.
+
+(4)
+ .. versionadded:: 2.5
+
+
+Deprecation of String Exceptions
+================================
+
+.. index:: single: BaseException (built-in exception)
+
+All exceptions built into Python or provided in the standard library are derived
+from :exc:`BaseException`.
+
+String exceptions are still supported in the interpreter to allow existing code
+to run unmodified, but this will also change in a future release.
+
diff --git a/Doc/c-api/index.rst b/Doc/c-api/index.rst
new file mode 100644
index 0000000000..c643312536
--- /dev/null
+++ b/Doc/c-api/index.rst
@@ -0,0 +1,33 @@
+.. _c-api-index:
+
+##################################
+ Python/C API Reference Manual
+##################################
+
+:Release: |version|
+:Date: |today|
+
+This manual documents the API used by C and C++ programmers who want to write
+extension modules or embed Python. It is a companion to :ref:`extending-index`,
+which describes the general principles of extension writing but does not
+document the API functions in detail.
+
+.. warning::
+
+ The current version of this document is somewhat incomplete. However, most of
+ the important functions, types and structures are described.
+
+
+.. toctree::
+ :maxdepth: 2
+
+ intro.rst
+ veryhigh.rst
+ refcounting.rst
+ exceptions.rst
+ utilities.rst
+ abstract.rst
+ concrete.rst
+ init.rst
+ memory.rst
+ newtypes.rst
diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst
new file mode 100644
index 0000000000..2509e0b699
--- /dev/null
+++ b/Doc/c-api/init.rst
@@ -0,0 +1,936 @@
+.. highlightlang:: c
+
+
+.. _initialization:
+
+*****************************************
+Initialization, Finalization, and Threads
+*****************************************
+
+
+.. cfunction:: void Py_Initialize()
+
+ .. index::
+ single: Py_SetProgramName()
+ single: PyEval_InitThreads()
+ single: PyEval_ReleaseLock()
+ single: PyEval_AcquireLock()
+ single: modules (in module sys)
+ single: path (in module sys)
+ module: __builtin__
+ module: __main__
+ module: sys
+ triple: module; search; path
+ single: PySys_SetArgv()
+ single: Py_Finalize()
+
+ Initialize the Python interpreter. In an application embedding Python, this
+ should be called before using any other Python/C API functions; with the
+ exception of :cfunc:`Py_SetProgramName`, :cfunc:`PyEval_InitThreads`,
+ :cfunc:`PyEval_ReleaseLock`, and :cfunc:`PyEval_AcquireLock`. This initializes
+ the table of loaded modules (``sys.modules``), and creates the fundamental
+ modules :mod:`__builtin__`, :mod:`__main__` and :mod:`sys`. It also initializes
+ the module search path (``sys.path``). It does not set ``sys.argv``; use
+ :cfunc:`PySys_SetArgv` for that. This is a no-op when called for a second time
+ (without calling :cfunc:`Py_Finalize` first). There is no return value; it is a
+ fatal error if the initialization fails.
+
+
+.. cfunction:: void Py_InitializeEx(int initsigs)
+
+ This function works like :cfunc:`Py_Initialize` if *initsigs* is 1. If
+ *initsigs* is 0, it skips initialization registration of signal handlers, which
+ might be useful when Python is embedded.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: int Py_IsInitialized()
+
+ Return true (nonzero) when the Python interpreter has been initialized, false
+ (zero) if not. After :cfunc:`Py_Finalize` is called, this returns false until
+ :cfunc:`Py_Initialize` is called again.
+
+
+.. cfunction:: void Py_Finalize()
+
+ Undo all initializations made by :cfunc:`Py_Initialize` and subsequent use of
+ Python/C API functions, and destroy all sub-interpreters (see
+ :cfunc:`Py_NewInterpreter` below) that were created and not yet destroyed since
+ the last call to :cfunc:`Py_Initialize`. Ideally, this frees all memory
+ allocated by the Python interpreter. This is a no-op when called for a second
+ time (without calling :cfunc:`Py_Initialize` again first). There is no return
+ value; errors during finalization are ignored.
+
+ This function is provided for a number of reasons. An embedding application
+ might want to restart Python without having to restart the application itself.
+ An application that has loaded the Python interpreter from a dynamically
+ loadable library (or DLL) might want to free all memory allocated by Python
+ before unloading the DLL. During a hunt for memory leaks in an application a
+ developer might want to free all memory allocated by Python before exiting from
+ the application.
+
+ **Bugs and caveats:** The destruction of modules and objects in modules is done
+ in random order; this may cause destructors (:meth:`__del__` methods) to fail
+ when they depend on other objects (even functions) or modules. Dynamically
+ loaded extension modules loaded by Python are not unloaded. Small amounts of
+ memory allocated by the Python interpreter may not be freed (if you find a leak,
+ please report it). Memory tied up in circular references between objects is not
+ freed. Some memory allocated by extension modules may not be freed. Some
+ extensions may not work properly if their initialization routine is called more
+ than once; this can happen if an application calls :cfunc:`Py_Initialize` and
+ :cfunc:`Py_Finalize` more than once.
+
+
+.. cfunction:: PyThreadState* Py_NewInterpreter()
+
+ .. index::
+ module: __builtin__
+ module: __main__
+ module: sys
+ single: stdout (in module sys)
+ single: stderr (in module sys)
+ single: stdin (in module sys)
+
+ Create a new sub-interpreter. This is an (almost) totally separate environment
+ for the execution of Python code. In particular, the new interpreter has
+ separate, independent versions of all imported modules, including the
+ fundamental modules :mod:`__builtin__`, :mod:`__main__` and :mod:`sys`. The
+ table of loaded modules (``sys.modules``) and the module search path
+ (``sys.path``) are also separate. The new environment has no ``sys.argv``
+ variable. It has new standard I/O stream file objects ``sys.stdin``,
+ ``sys.stdout`` and ``sys.stderr`` (however these refer to the same underlying
+ :ctype:`FILE` structures in the C library).
+
+ The return value points to the first thread state created in the new
+ sub-interpreter. This thread state is made in the current thread state.
+ Note that no actual thread is created; see the discussion of thread states
+ below. If creation of the new interpreter is unsuccessful, *NULL* is
+ returned; no exception is set since the exception state is stored in the
+ current thread state and there may not be a current thread state. (Like all
+ other Python/C API functions, the global interpreter lock must be held before
+ calling this function and is still held when it returns; however, unlike most
+ other Python/C API functions, there needn't be a current thread state on
+ entry.)
+
+ .. index::
+ single: Py_Finalize()
+ single: Py_Initialize()
+
+ Extension modules are shared between (sub-)interpreters as follows: the first
+ time a particular extension is imported, it is initialized normally, and a
+ (shallow) copy of its module's dictionary is squirreled away. When the same
+ extension is imported by another (sub-)interpreter, a new module is initialized
+ and filled with the contents of this copy; the extension's ``init`` function is
+ not called. Note that this is different from what happens when an extension is
+ imported after the interpreter has been completely re-initialized by calling
+ :cfunc:`Py_Finalize` and :cfunc:`Py_Initialize`; in that case, the extension's
+ ``initmodule`` function *is* called again.
+
+ .. index:: single: close() (in module os)
+
+ **Bugs and caveats:** Because sub-interpreters (and the main interpreter) are
+ part of the same process, the insulation between them isn't perfect --- for
+ example, using low-level file operations like :func:`os.close` they can
+ (accidentally or maliciously) affect each other's open files. Because of the
+ way extensions are shared between (sub-)interpreters, some extensions may not
+ work properly; this is especially likely when the extension makes use of
+ (static) global variables, or when the extension manipulates its module's
+ dictionary after its initialization. It is possible to insert objects created
+ in one sub-interpreter into a namespace of another sub-interpreter; this should
+ be done with great care to avoid sharing user-defined functions, methods,
+ instances or classes between sub-interpreters, since import operations executed
+ by such objects may affect the wrong (sub-)interpreter's dictionary of loaded
+ modules. (XXX This is a hard-to-fix bug that will be addressed in a future
+ release.)
+
+ Also note that the use of this functionality is incompatible with extension
+ modules such as PyObjC and ctypes that use the :cfunc:`PyGILState_\*` APIs (and
+ this is inherent in the way the :cfunc:`PyGILState_\*` functions work). Simple
+ things may work, but confusing behavior will always be near.
+
+
+.. cfunction:: void Py_EndInterpreter(PyThreadState *tstate)
+
+ .. index:: single: Py_Finalize()
+
+ Destroy the (sub-)interpreter represented by the given thread state. The given
+ thread state must be the current thread state. See the discussion of thread
+ states below. When the call returns, the current thread state is *NULL*. All
+ thread states associated with this interpreter are destroyed. (The global
+ interpreter lock must be held before calling this function and is still held
+ when it returns.) :cfunc:`Py_Finalize` will destroy all sub-interpreters that
+ haven't been explicitly destroyed at that point.
+
+
+.. cfunction:: void Py_SetProgramName(char *name)
+
+ .. index::
+ single: Py_Initialize()
+ single: main()
+ single: Py_GetPath()
+
+ This function should be called before :cfunc:`Py_Initialize` is called for
+ the first time, if it is called at all. It tells the interpreter the value
+ of the ``argv[0]`` argument to the :cfunc:`main` function of the program.
+ This is used by :cfunc:`Py_GetPath` and some other functions below to find
+ the Python run-time libraries relative to the interpreter executable. The
+ default value is ``'python'``. The argument should point to a
+ zero-terminated character string in static storage whose contents will not
+ change for the duration of the program's execution. No code in the Python
+ interpreter will change the contents of this storage.
+
+
+.. cfunction:: char* Py_GetProgramName()
+
+ .. index:: single: Py_SetProgramName()
+
+ Return the program name set with :cfunc:`Py_SetProgramName`, or the default.
+ The returned string points into static storage; the caller should not modify its
+ value.
+
+
+.. cfunction:: char* Py_GetPrefix()
+
+ Return the *prefix* for installed platform-independent files. This is derived
+ through a number of complicated rules from the program name set with
+ :cfunc:`Py_SetProgramName` and some environment variables; for example, if the
+ program name is ``'/usr/local/bin/python'``, the prefix is ``'/usr/local'``. The
+ returned string points into static storage; the caller should not modify its
+ value. This corresponds to the :makevar:`prefix` variable in the top-level
+ :file:`Makefile` and the :option:`--prefix` argument to the :program:`configure`
+ script at build time. The value is available to Python code as ``sys.prefix``.
+ It is only useful on Unix. See also the next function.
+
+
+.. cfunction:: char* Py_GetExecPrefix()
+
+ Return the *exec-prefix* for installed platform-*dependent* files. This is
+ derived through a number of complicated rules from the program name set with
+ :cfunc:`Py_SetProgramName` and some environment variables; for example, if the
+ program name is ``'/usr/local/bin/python'``, the exec-prefix is
+ ``'/usr/local'``. The returned string points into static storage; the caller
+ should not modify its value. This corresponds to the :makevar:`exec_prefix`
+ variable in the top-level :file:`Makefile` and the :option:`--exec-prefix`
+ argument to the :program:`configure` script at build time. The value is
+ available to Python code as ``sys.exec_prefix``. It is only useful on Unix.
+
+ Background: The exec-prefix differs from the prefix when platform dependent
+ files (such as executables and shared libraries) are installed in a different
+ directory tree. In a typical installation, platform dependent files may be
+ installed in the :file:`/usr/local/plat` subtree while platform independent may
+ be installed in :file:`/usr/local`.
+
+ Generally speaking, a platform is a combination of hardware and software
+ families, e.g. Sparc machines running the Solaris 2.x operating system are
+ considered the same platform, but Intel machines running Solaris 2.x are another
+ platform, and Intel machines running Linux are yet another platform. Different
+ major revisions of the same operating system generally also form different
+ platforms. Non-Unix operating systems are a different story; the installation
+ strategies on those systems are so different that the prefix and exec-prefix are
+ meaningless, and set to the empty string. Note that compiled Python bytecode
+ files are platform independent (but not independent from the Python version by
+ which they were compiled!).
+
+ System administrators will know how to configure the :program:`mount` or
+ :program:`automount` programs to share :file:`/usr/local` between platforms
+ while having :file:`/usr/local/plat` be a different filesystem for each
+ platform.
+
+
+.. cfunction:: char* Py_GetProgramFullPath()
+
+ .. index::
+ single: Py_SetProgramName()
+ single: executable (in module sys)
+
+ Return the full program name of the Python executable; this is computed as a
+ side-effect of deriving the default module search path from the program name
+ (set by :cfunc:`Py_SetProgramName` above). The returned string points into
+ static storage; the caller should not modify its value. The value is available
+ to Python code as ``sys.executable``.
+
+
+.. cfunction:: char* Py_GetPath()
+
+ .. index::
+ triple: module; search; path
+ single: path (in module sys)
+
+ Return the default module search path; this is computed from the program name
+ (set by :cfunc:`Py_SetProgramName` above) and some environment variables. The
+ returned string consists of a series of directory names separated by a platform
+ dependent delimiter character. The delimiter character is ``':'`` on Unix and
+ Mac OS X, ``';'`` on Windows. The returned string points into static storage;
+ the caller should not modify its value. The value is available to Python code
+ as the list ``sys.path``, which may be modified to change the future search path
+ for loaded modules.
+
+ .. % XXX should give the exact rules
+
+
+.. cfunction:: const char* Py_GetVersion()
+
+ Return the version of this Python interpreter. This is a string that looks
+ something like ::
+
+ "1.5 (#67, Dec 31 1997, 22:34:28) [GCC 2.7.2.2]"
+
+ .. index:: single: version (in module sys)
+
+ The first word (up to the first space character) is the current Python version;
+ the first three characters are the major and minor version separated by a
+ period. The returned string points into static storage; the caller should not
+ modify its value. The value is available to Python code as ``sys.version``.
+
+
+.. cfunction:: const char* Py_GetBuildNumber()
+
+ Return a string representing the Subversion revision that this Python executable
+ was built from. This number is a string because it may contain a trailing 'M'
+ if Python was built from a mixed revision source tree.
+
+ .. versionadded:: 2.5
+
+
+.. cfunction:: const char* Py_GetPlatform()
+
+ .. index:: single: platform (in module sys)
+
+ Return the platform identifier for the current platform. On Unix, this is
+ formed from the "official" name of the operating system, converted to lower
+ case, followed by the major revision number; e.g., for Solaris 2.x, which is
+ also known as SunOS 5.x, the value is ``'sunos5'``. On Mac OS X, it is
+ ``'darwin'``. On Windows, it is ``'win'``. The returned string points into
+ static storage; the caller should not modify its value. The value is available
+ to Python code as ``sys.platform``.
+
+
+.. cfunction:: const char* Py_GetCopyright()
+
+ Return the official copyright string for the current Python version, for example
+
+ ``'Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam'``
+
+ .. index:: single: copyright (in module sys)
+
+ The returned string points into static storage; the caller should not modify its
+ value. The value is available to Python code as ``sys.copyright``.
+
+
+.. cfunction:: const char* Py_GetCompiler()
+
+ Return an indication of the compiler used to build the current Python version,
+ in square brackets, for example::
+
+ "[GCC 2.7.2.2]"
+
+ .. index:: single: version (in module sys)
+
+ The returned string points into static storage; the caller should not modify its
+ value. The value is available to Python code as part of the variable
+ ``sys.version``.
+
+
+.. cfunction:: const char* Py_GetBuildInfo()
+
+ Return information about the sequence number and build date and time of the
+ current Python interpreter instance, for example ::
+
+ "#67, Aug 1 1997, 22:34:28"
+
+ .. index:: single: version (in module sys)
+
+ The returned string points into static storage; the caller should not modify its
+ value. The value is available to Python code as part of the variable
+ ``sys.version``.
+
+
+.. cfunction:: void PySys_SetArgv(int argc, char **argv)
+
+ .. index::
+ single: main()
+ single: Py_FatalError()
+ single: argv (in module sys)
+
+ Set ``sys.argv`` based on *argc* and *argv*. These parameters are similar to
+ those passed to the program's :cfunc:`main` function with the difference that
+ the first entry should refer to the script file to be executed rather than the
+ executable hosting the Python interpreter. If there isn't a script that will be
+ run, the first entry in *argv* can be an empty string. If this function fails
+ to initialize ``sys.argv``, a fatal condition is signalled using
+ :cfunc:`Py_FatalError`.
+
+ .. % XXX impl. doesn't seem consistent in allowing 0/NULL for the params;
+ .. % check w/ Guido.
+
+.. % XXX Other PySys thingies (doesn't really belong in this chapter)
+
+
+.. _threads:
+
+Thread State and the Global Interpreter Lock
+============================================
+
+.. index::
+ single: global interpreter lock
+ single: interpreter lock
+ single: lock, interpreter
+
+The Python interpreter is not fully thread safe. In order to support
+multi-threaded Python programs, there's a global lock that must be held by the
+current thread before it can safely access Python objects. Without the lock,
+even the simplest operations could cause problems in a multi-threaded program:
+for example, when two threads simultaneously increment the reference count of
+the same object, the reference count could end up being incremented only once
+instead of twice.
+
+.. index:: single: setcheckinterval() (in module sys)
+
+Therefore, the rule exists that only the thread that has acquired the global
+interpreter lock may operate on Python objects or call Python/C API functions.
+In order to support multi-threaded Python programs, the interpreter regularly
+releases and reacquires the lock --- by default, every 100 bytecode instructions
+(this can be changed with :func:`sys.setcheckinterval`). The lock is also
+released and reacquired around potentially blocking I/O operations like reading
+or writing a file, so that other threads can run while the thread that requests
+the I/O is waiting for the I/O operation to complete.
+
+.. index::
+ single: PyThreadState
+ single: PyThreadState
+
+The Python interpreter needs to keep some bookkeeping information separate per
+thread --- for this it uses a data structure called :ctype:`PyThreadState`.
+There's one global variable, however: the pointer to the current
+:ctype:`PyThreadState` structure. While most thread packages have a way to
+store "per-thread global data," Python's internal platform independent thread
+abstraction doesn't support this yet. Therefore, the current thread state must
+be manipulated explicitly.
+
+This is easy enough in most cases. Most code manipulating the global
+interpreter lock has the following simple structure::
+
+ Save the thread state in a local variable.
+ Release the interpreter lock.
+ ...Do some blocking I/O operation...
+ Reacquire the interpreter lock.
+ Restore the thread state from the local variable.
+
+This is so common that a pair of macros exists to simplify it::
+
+ Py_BEGIN_ALLOW_THREADS
+ ...Do some blocking I/O operation...
+ Py_END_ALLOW_THREADS
+
+.. index::
+ single: Py_BEGIN_ALLOW_THREADS
+ single: Py_END_ALLOW_THREADS
+
+The :cmacro:`Py_BEGIN_ALLOW_THREADS` macro opens a new block and declares a
+hidden local variable; the :cmacro:`Py_END_ALLOW_THREADS` macro closes the
+block. Another advantage of using these two macros is that when Python is
+compiled without thread support, they are defined empty, thus saving the thread
+state and lock manipulations.
+
+When thread support is enabled, the block above expands to the following code::
+
+ PyThreadState *_save;
+
+ _save = PyEval_SaveThread();
+ ...Do some blocking I/O operation...
+ PyEval_RestoreThread(_save);
+
+Using even lower level primitives, we can get roughly the same effect as
+follows::
+
+ PyThreadState *_save;
+
+ _save = PyThreadState_Swap(NULL);
+ PyEval_ReleaseLock();
+ ...Do some blocking I/O operation...
+ PyEval_AcquireLock();
+ PyThreadState_Swap(_save);
+
+.. index::
+ single: PyEval_RestoreThread()
+ single: errno
+ single: PyEval_SaveThread()
+ single: PyEval_ReleaseLock()
+ single: PyEval_AcquireLock()
+
+There are some subtle differences; in particular, :cfunc:`PyEval_RestoreThread`
+saves and restores the value of the global variable :cdata:`errno`, since the
+lock manipulation does not guarantee that :cdata:`errno` is left alone. Also,
+when thread support is disabled, :cfunc:`PyEval_SaveThread` and
+:cfunc:`PyEval_RestoreThread` don't manipulate the lock; in this case,
+:cfunc:`PyEval_ReleaseLock` and :cfunc:`PyEval_AcquireLock` are not available.
+This is done so that dynamically loaded extensions compiled with thread support
+enabled can be loaded by an interpreter that was compiled with disabled thread
+support.
+
+The global interpreter lock is used to protect the pointer to the current thread
+state. When releasing the lock and saving the thread state, the current thread
+state pointer must be retrieved before the lock is released (since another
+thread could immediately acquire the lock and store its own thread state in the
+global variable). Conversely, when acquiring the lock and restoring the thread
+state, the lock must be acquired before storing the thread state pointer.
+
+Why am I going on with so much detail about this? Because when threads are
+created from C, they don't have the global interpreter lock, nor is there a
+thread state data structure for them. Such threads must bootstrap themselves
+into existence, by first creating a thread state data structure, then acquiring
+the lock, and finally storing their thread state pointer, before they can start
+using the Python/C API. When they are done, they should reset the thread state
+pointer, release the lock, and finally free their thread state data structure.
+
+Beginning with version 2.3, threads can now take advantage of the
+:cfunc:`PyGILState_\*` functions to do all of the above automatically. The
+typical idiom for calling into Python from a C thread is now::
+
+ PyGILState_STATE gstate;
+ gstate = PyGILState_Ensure();
+
+ /* Perform Python actions here. */
+ result = CallSomeFunction();
+ /* evaluate result */
+
+ /* Release the thread. No Python API allowed beyond this point. */
+ PyGILState_Release(gstate);
+
+Note that the :cfunc:`PyGILState_\*` functions assume there is only one global
+interpreter (created automatically by :cfunc:`Py_Initialize`). Python still
+supports the creation of additional interpreters (using
+:cfunc:`Py_NewInterpreter`), but mixing multiple interpreters and the
+:cfunc:`PyGILState_\*` API is unsupported.
+
+
+.. ctype:: PyInterpreterState
+
+ This data structure represents the state shared by a number of cooperating
+ threads. Threads belonging to the same interpreter share their module
+ administration and a few other internal items. There are no public members in
+ this structure.
+
+ Threads belonging to different interpreters initially share nothing, except
+ process state like available memory, open file descriptors and such. The global
+ interpreter lock is also shared by all threads, regardless of to which
+ interpreter they belong.
+
+
+.. ctype:: PyThreadState
+
+ This data structure represents the state of a single thread. The only public
+ data member is :ctype:`PyInterpreterState \*`:attr:`interp`, which points to
+ this thread's interpreter state.
+
+
+.. cfunction:: void PyEval_InitThreads()
+
+ .. index::
+ single: PyEval_ReleaseLock()
+ single: PyEval_ReleaseThread()
+ single: PyEval_SaveThread()
+ single: PyEval_RestoreThread()
+
+ Initialize and acquire the global interpreter lock. It should be called in the
+ main thread before creating a second thread or engaging in any other thread
+ operations such as :cfunc:`PyEval_ReleaseLock` or
+ ``PyEval_ReleaseThread(tstate)``. It is not needed before calling
+ :cfunc:`PyEval_SaveThread` or :cfunc:`PyEval_RestoreThread`.
+
+ .. index:: single: Py_Initialize()
+
+ This is a no-op when called for a second time. It is safe to call this function
+ before calling :cfunc:`Py_Initialize`.
+
+ .. index:: module: thread
+
+ When only the main thread exists, no lock operations are needed. This is a
+ common situation (most Python programs do not use threads), and the lock
+ operations slow the interpreter down a bit. Therefore, the lock is not created
+ initially. This situation is equivalent to having acquired the lock: when
+ there is only a single thread, all object accesses are safe. Therefore, when
+ this function initializes the lock, it also acquires it. Before the Python
+ :mod:`thread` module creates a new thread, knowing that either it has the lock
+ or the lock hasn't been created yet, it calls :cfunc:`PyEval_InitThreads`. When
+ this call returns, it is guaranteed that the lock has been created and that the
+ calling thread has acquired it.
+
+ It is **not** safe to call this function when it is unknown which thread (if
+ any) currently has the global interpreter lock.
+
+ This function is not available when thread support is disabled at compile time.
+
+
+.. cfunction:: int PyEval_ThreadsInitialized()
+
+ Returns a non-zero value if :cfunc:`PyEval_InitThreads` has been called. This
+ function can be called without holding the lock, and therefore can be used to
+ avoid calls to the locking API when running single-threaded. This function is
+ not available when thread support is disabled at compile time.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: void PyEval_AcquireLock()
+
+ Acquire the global interpreter lock. The lock must have been created earlier.
+ If this thread already has the lock, a deadlock ensues. This function is not
+ available when thread support is disabled at compile time.
+
+
+.. cfunction:: void PyEval_ReleaseLock()
+
+ Release the global interpreter lock. The lock must have been created earlier.
+ This function is not available when thread support is disabled at compile time.
+
+
+.. cfunction:: void PyEval_AcquireThread(PyThreadState *tstate)
+
+ Acquire the global interpreter lock and set the current thread state to
+ *tstate*, which should not be *NULL*. The lock must have been created earlier.
+ If this thread already has the lock, deadlock ensues. This function is not
+ available when thread support is disabled at compile time.
+
+
+.. cfunction:: void PyEval_ReleaseThread(PyThreadState *tstate)
+
+ Reset the current thread state to *NULL* and release the global interpreter
+ lock. The lock must have been created earlier and must be held by the current
+ thread. The *tstate* argument, which must not be *NULL*, is only used to check
+ that it represents the current thread state --- if it isn't, a fatal error is
+ reported. This function is not available when thread support is disabled at
+ compile time.
+
+
+.. cfunction:: PyThreadState* PyEval_SaveThread()
+
+ Release the interpreter lock (if it has been created and thread support is
+ enabled) and reset the thread state to *NULL*, returning the previous thread
+ state (which is not *NULL*). If the lock has been created, the current thread
+ must have acquired it. (This function is available even when thread support is
+ disabled at compile time.)
+
+
+.. cfunction:: void PyEval_RestoreThread(PyThreadState *tstate)
+
+ Acquire the interpreter lock (if it has been created and thread support is
+ enabled) and set the thread state to *tstate*, which must not be *NULL*. If the
+ lock has been created, the current thread must not have acquired it, otherwise
+ deadlock ensues. (This function is available even when thread support is
+ disabled at compile time.)
+
+The following macros are normally used without a trailing semicolon; look for
+example usage in the Python source distribution.
+
+
+.. cmacro:: Py_BEGIN_ALLOW_THREADS
+
+ This macro expands to ``{ PyThreadState *_save; _save = PyEval_SaveThread();``.
+ Note that it contains an opening brace; it must be matched with a following
+ :cmacro:`Py_END_ALLOW_THREADS` macro. See above for further discussion of this
+ macro. It is a no-op when thread support is disabled at compile time.
+
+
+.. cmacro:: Py_END_ALLOW_THREADS
+
+ This macro expands to ``PyEval_RestoreThread(_save); }``. Note that it contains
+ a closing brace; it must be matched with an earlier
+ :cmacro:`Py_BEGIN_ALLOW_THREADS` macro. See above for further discussion of
+ this macro. It is a no-op when thread support is disabled at compile time.
+
+
+.. cmacro:: Py_BLOCK_THREADS
+
+ This macro expands to ``PyEval_RestoreThread(_save);``: it is equivalent to
+ :cmacro:`Py_END_ALLOW_THREADS` without the closing brace. It is a no-op when
+ thread support is disabled at compile time.
+
+
+.. cmacro:: Py_UNBLOCK_THREADS
+
+ This macro expands to ``_save = PyEval_SaveThread();``: it is equivalent to
+ :cmacro:`Py_BEGIN_ALLOW_THREADS` without the opening brace and variable
+ declaration. It is a no-op when thread support is disabled at compile time.
+
+All of the following functions are only available when thread support is enabled
+at compile time, and must be called only when the interpreter lock has been
+created.
+
+
+.. cfunction:: PyInterpreterState* PyInterpreterState_New()
+
+ Create a new interpreter state object. The interpreter lock need not be held,
+ but may be held if it is necessary to serialize calls to this function.
+
+
+.. cfunction:: void PyInterpreterState_Clear(PyInterpreterState *interp)
+
+ Reset all information in an interpreter state object. The interpreter lock must
+ be held.
+
+
+.. cfunction:: void PyInterpreterState_Delete(PyInterpreterState *interp)
+
+ Destroy an interpreter state object. The interpreter lock need not be held.
+ The interpreter state must have been reset with a previous call to
+ :cfunc:`PyInterpreterState_Clear`.
+
+
+.. cfunction:: PyThreadState* PyThreadState_New(PyInterpreterState *interp)
+
+ Create a new thread state object belonging to the given interpreter object. The
+ interpreter lock need not be held, but may be held if it is necessary to
+ serialize calls to this function.
+
+
+.. cfunction:: void PyThreadState_Clear(PyThreadState *tstate)
+
+ Reset all information in a thread state object. The interpreter lock must be
+ held.
+
+
+.. cfunction:: void PyThreadState_Delete(PyThreadState *tstate)
+
+ Destroy a thread state object. The interpreter lock need not be held. The
+ thread state must have been reset with a previous call to
+ :cfunc:`PyThreadState_Clear`.
+
+
+.. cfunction:: PyThreadState* PyThreadState_Get()
+
+ Return the current thread state. The interpreter lock must be held. When the
+ current thread state is *NULL*, this issues a fatal error (so that the caller
+ needn't check for *NULL*).
+
+
+.. cfunction:: PyThreadState* PyThreadState_Swap(PyThreadState *tstate)
+
+ Swap the current thread state with the thread state given by the argument
+ *tstate*, which may be *NULL*. The interpreter lock must be held.
+
+
+.. cfunction:: PyObject* PyThreadState_GetDict()
+
+ Return a dictionary in which extensions can store thread-specific state
+ information. Each extension should use a unique key to use to store state in
+ the dictionary. It is okay to call this function when no current thread state
+ is available. If this function returns *NULL*, no exception has been raised and
+ the caller should assume no current thread state is available.
+
+ .. versionchanged:: 2.3
+ Previously this could only be called when a current thread is active, and *NULL*
+ meant that an exception was raised.
+
+
+.. cfunction:: int PyThreadState_SetAsyncExc(long id, PyObject *exc)
+
+ Asynchronously raise an exception in a thread. The *id* argument is the thread
+ id of the target thread; *exc* is the exception object to be raised. This
+ function does not steal any references to *exc*. To prevent naive misuse, you
+ must write your own C extension to call this. Must be called with the GIL held.
+ Returns the number of thread states modified; this is normally one, but will be
+ zero if the thread id isn't found. If *exc* is :const:`NULL`, the pending
+ exception (if any) for the thread is cleared. This raises no exceptions.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: PyGILState_STATE PyGILState_Ensure()
+
+ Ensure that the current thread is ready to call the Python C API regardless of
+ the current state of Python, or of its thread lock. This may be called as many
+ times as desired by a thread as long as each call is matched with a call to
+ :cfunc:`PyGILState_Release`. In general, other thread-related APIs may be used
+ between :cfunc:`PyGILState_Ensure` and :cfunc:`PyGILState_Release` calls as long
+ as the thread state is restored to its previous state before the Release(). For
+ example, normal usage of the :cmacro:`Py_BEGIN_ALLOW_THREADS` and
+ :cmacro:`Py_END_ALLOW_THREADS` macros is acceptable.
+
+ The return value is an opaque "handle" to the thread state when
+ :cfunc:`PyGILState_Acquire` was called, and must be passed to
+ :cfunc:`PyGILState_Release` to ensure Python is left in the same state. Even
+ though recursive calls are allowed, these handles *cannot* be shared - each
+ unique call to :cfunc:`PyGILState_Ensure` must save the handle for its call to
+ :cfunc:`PyGILState_Release`.
+
+ When the function returns, the current thread will hold the GIL. Failure is a
+ fatal error.
+
+ .. versionadded:: 2.3
+
+
+.. cfunction:: void PyGILState_Release(PyGILState_STATE)
+
+ Release any resources previously acquired. After this call, Python's state will
+ be the same as it was prior to the corresponding :cfunc:`PyGILState_Ensure` call
+ (but generally this state will be unknown to the caller, hence the use of the
+ GILState API.)
+
+ Every call to :cfunc:`PyGILState_Ensure` must be matched by a call to
+ :cfunc:`PyGILState_Release` on the same thread.
+
+ .. versionadded:: 2.3
+
+
+.. _profiling:
+
+Profiling and Tracing
+=====================
+
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The Python interpreter provides some low-level support for attaching profiling
+and execution tracing facilities. These are used for profiling, debugging, and
+coverage analysis tools.
+
+Starting with Python 2.2, the implementation of this facility was substantially
+revised, and an interface from C was added. This C interface allows the
+profiling or tracing code to avoid the overhead of calling through Python-level
+callable objects, making a direct C function call instead. The essential
+attributes of the facility have not changed; the interface allows trace
+functions to be installed per-thread, and the basic events reported to the trace
+function are the same as had been reported to the Python-level trace functions
+in previous versions.
+
+
+.. ctype:: int (*Py_tracefunc)(PyObject *obj, PyFrameObject *frame, int what, PyObject *arg)
+
+ The type of the trace function registered using :cfunc:`PyEval_SetProfile` and
+ :cfunc:`PyEval_SetTrace`. The first parameter is the object passed to the
+ registration function as *obj*, *frame* is the frame object to which the event
+ pertains, *what* is one of the constants :const:`PyTrace_CALL`,
+ :const:`PyTrace_EXCEPTION`, :const:`PyTrace_LINE`, :const:`PyTrace_RETURN`,
+ :const:`PyTrace_C_CALL`, :const:`PyTrace_C_EXCEPTION`, or
+ :const:`PyTrace_C_RETURN`, and *arg* depends on the value of *what*:
+
+ +------------------------------+--------------------------------------+
+ | Value of *what* | Meaning of *arg* |
+ +==============================+======================================+
+ | :const:`PyTrace_CALL` | Always *NULL*. |
+ +------------------------------+--------------------------------------+
+ | :const:`PyTrace_EXCEPTION` | Exception information as returned by |
+ | | :func:`sys.exc_info`. |
+ +------------------------------+--------------------------------------+
+ | :const:`PyTrace_LINE` | Always *NULL*. |
+ +------------------------------+--------------------------------------+
+ | :const:`PyTrace_RETURN` | Value being returned to the caller. |
+ +------------------------------+--------------------------------------+
+ | :const:`PyTrace_C_CALL` | Name of function being called. |
+ +------------------------------+--------------------------------------+
+ | :const:`PyTrace_C_EXCEPTION` | Always *NULL*. |
+ +------------------------------+--------------------------------------+
+ | :const:`PyTrace_C_RETURN` | Always *NULL*. |
+ +------------------------------+--------------------------------------+
+
+
+.. cvar:: int PyTrace_CALL
+
+ The value of the *what* parameter to a :ctype:`Py_tracefunc` function when a new
+ call to a function or method is being reported, or a new entry into a generator.
+ Note that the creation of the iterator for a generator function is not reported
+ as there is no control transfer to the Python bytecode in the corresponding
+ frame.
+
+
+.. cvar:: int PyTrace_EXCEPTION
+
+ The value of the *what* parameter to a :ctype:`Py_tracefunc` function when an
+ exception has been raised. The callback function is called with this value for
+ *what* when after any bytecode is processed after which the exception becomes
+ set within the frame being executed. The effect of this is that as exception
+ propagation causes the Python stack to unwind, the callback is called upon
+ return to each frame as the exception propagates. Only trace functions receives
+ these events; they are not needed by the profiler.
+
+
+.. cvar:: int PyTrace_LINE
+
+ The value passed as the *what* parameter to a trace function (but not a
+ profiling function) when a line-number event is being reported.
+
+
+.. cvar:: int PyTrace_RETURN
+
+ The value for the *what* parameter to :ctype:`Py_tracefunc` functions when a
+ call is returning without propagating an exception.
+
+
+.. cvar:: int PyTrace_C_CALL
+
+ The value for the *what* parameter to :ctype:`Py_tracefunc` functions when a C
+ function is about to be called.
+
+
+.. cvar:: int PyTrace_C_EXCEPTION
+
+ The value for the *what* parameter to :ctype:`Py_tracefunc` functions when a C
+ function has thrown an exception.
+
+
+.. cvar:: int PyTrace_C_RETURN
+
+ The value for the *what* parameter to :ctype:`Py_tracefunc` functions when a C
+ function has returned.
+
+
+.. cfunction:: void PyEval_SetProfile(Py_tracefunc func, PyObject *obj)
+
+ Set the profiler function to *func*. The *obj* parameter is passed to the
+ function as its first parameter, and may be any Python object, or *NULL*. If
+ the profile function needs to maintain state, using a different value for *obj*
+ for each thread provides a convenient and thread-safe place to store it. The
+ profile function is called for all monitored events except the line-number
+ events.
+
+
+.. cfunction:: void PyEval_SetTrace(Py_tracefunc func, PyObject *obj)
+
+ Set the tracing function to *func*. This is similar to
+ :cfunc:`PyEval_SetProfile`, except the tracing function does receive line-number
+ events.
+
+
+.. _advanced-debugging:
+
+Advanced Debugger Support
+=========================
+
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+These functions are only intended to be used by advanced debugging tools.
+
+
+.. cfunction:: PyInterpreterState* PyInterpreterState_Head()
+
+ Return the interpreter state object at the head of the list of all such objects.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyInterpreterState* PyInterpreterState_Next(PyInterpreterState *interp)
+
+ Return the next interpreter state object after *interp* from the list of all
+ such objects.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyThreadState * PyInterpreterState_ThreadHead(PyInterpreterState *interp)
+
+ Return the a pointer to the first :ctype:`PyThreadState` object in the list of
+ threads associated with the interpreter *interp*.
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyThreadState* PyThreadState_Next(PyThreadState *tstate)
+
+ Return the next thread state object after *tstate* from the list of all such
+ objects belonging to the same :ctype:`PyInterpreterState` object.
+
+ .. versionadded:: 2.2
+
diff --git a/Doc/c-api/intro.rst b/Doc/c-api/intro.rst
new file mode 100644
index 0000000000..60b00521f4
--- /dev/null
+++ b/Doc/c-api/intro.rst
@@ -0,0 +1,630 @@
+.. highlightlang:: c
+
+
+.. _api-intro:
+
+************
+Introduction
+************
+
+The Application Programmer's Interface to Python gives C and C++ programmers
+access to the Python interpreter at a variety of levels. The API is equally
+usable from C++, but for brevity it is generally referred to as the Python/C
+API. There are two fundamentally different reasons for using the Python/C API.
+The first reason is to write *extension modules* for specific purposes; these
+are C modules that extend the Python interpreter. This is probably the most
+common use. The second reason is to use Python as a component in a larger
+application; this technique is generally referred to as :dfn:`embedding` Python
+in an application.
+
+Writing an extension module is a relatively well-understood process, where a
+"cookbook" approach works well. There are several tools that automate the
+process to some extent. While people have embedded Python in other
+applications since its early existence, the process of embedding Python is less
+straightforward than writing an extension.
+
+Many API functions are useful independent of whether you're embedding or
+extending Python; moreover, most applications that embed Python will need to
+provide a custom extension as well, so it's probably a good idea to become
+familiar with writing an extension before attempting to embed Python in a real
+application.
+
+
+.. _api-includes:
+
+Include Files
+=============
+
+All function, type and macro definitions needed to use the Python/C API are
+included in your code by the following line::
+
+ #include "Python.h"
+
+This implies inclusion of the following standard headers: ``<stdio.h>``,
+``<string.h>``, ``<errno.h>``, ``<limits.h>``, and ``<stdlib.h>`` (if
+available).
+
+.. warning::
+
+ Since Python may define some pre-processor definitions which affect the standard
+ headers on some systems, you *must* include :file:`Python.h` before any standard
+ headers are included.
+
+All user visible names defined by Python.h (except those defined by the included
+standard headers) have one of the prefixes ``Py`` or ``_Py``. Names beginning
+with ``_Py`` are for internal use by the Python implementation and should not be
+used by extension writers. Structure member names do not have a reserved prefix.
+
+**Important:** user code should never define names that begin with ``Py`` or
+``_Py``. This confuses the reader, and jeopardizes the portability of the user
+code to future Python versions, which may define additional names beginning with
+one of these prefixes.
+
+The header files are typically installed with Python. On Unix, these are
+located in the directories :file:`{prefix}/include/pythonversion/` and
+:file:`{exec_prefix}/include/pythonversion/`, where :envvar:`prefix` and
+:envvar:`exec_prefix` are defined by the corresponding parameters to Python's
+:program:`configure` script and *version* is ``sys.version[:3]``. On Windows,
+the headers are installed in :file:`{prefix}/include`, where :envvar:`prefix` is
+the installation directory specified to the installer.
+
+To include the headers, place both directories (if different) on your compiler's
+search path for includes. Do *not* place the parent directories on the search
+path and then use ``#include <pythonX.Y/Python.h>``; this will break on
+multi-platform builds since the platform independent headers under
+:envvar:`prefix` include the platform specific headers from
+:envvar:`exec_prefix`.
+
+C++ users should note that though the API is defined entirely using C, the
+header files do properly declare the entry points to be ``extern "C"``, so there
+is no need to do anything special to use the API from C++.
+
+
+.. _api-objects:
+
+Objects, Types and Reference Counts
+===================================
+
+.. index:: object: type
+
+Most Python/C API functions have one or more arguments as well as a return value
+of type :ctype:`PyObject\*`. This type is a pointer to an opaque data type
+representing an arbitrary Python object. Since all Python object types are
+treated the same way by the Python language in most situations (e.g.,
+assignments, scope rules, and argument passing), it is only fitting that they
+should be represented by a single C type. Almost all Python objects live on the
+heap: you never declare an automatic or static variable of type
+:ctype:`PyObject`, only pointer variables of type :ctype:`PyObject\*` can be
+declared. The sole exception are the type objects; since these must never be
+deallocated, they are typically static :ctype:`PyTypeObject` objects.
+
+All Python objects (even Python integers) have a :dfn:`type` and a
+:dfn:`reference count`. An object's type determines what kind of object it is
+(e.g., an integer, a list, or a user-defined function; there are many more as
+explained in :ref:`types`). For each of the well-known types there is a macro
+to check whether an object is of that type; for instance, ``PyList_Check(a)`` is
+true if (and only if) the object pointed to by *a* is a Python list.
+
+
+.. _api-refcounts:
+
+Reference Counts
+----------------
+
+The reference count is important because today's computers have a finite (and
+often severely limited) memory size; it counts how many different places there
+are that have a reference to an object. Such a place could be another object,
+or a global (or static) C variable, or a local variable in some C function.
+When an object's reference count becomes zero, the object is deallocated. If
+it contains references to other objects, their reference count is decremented.
+Those other objects may be deallocated in turn, if this decrement makes their
+reference count become zero, and so on. (There's an obvious problem with
+objects that reference each other here; for now, the solution is "don't do
+that.")
+
+.. index::
+ single: Py_INCREF()
+ single: Py_DECREF()
+
+Reference counts are always manipulated explicitly. The normal way is to use
+the macro :cfunc:`Py_INCREF` to increment an object's reference count by one,
+and :cfunc:`Py_DECREF` to decrement it by one. The :cfunc:`Py_DECREF` macro
+is considerably more complex than the incref one, since it must check whether
+the reference count becomes zero and then cause the object's deallocator to be
+called. The deallocator is a function pointer contained in the object's type
+structure. The type-specific deallocator takes care of decrementing the
+reference counts for other objects contained in the object if this is a compound
+object type, such as a list, as well as performing any additional finalization
+that's needed. There's no chance that the reference count can overflow; at
+least as many bits are used to hold the reference count as there are distinct
+memory locations in virtual memory (assuming ``sizeof(long) >= sizeof(char*)``).
+Thus, the reference count increment is a simple operation.
+
+It is not necessary to increment an object's reference count for every local
+variable that contains a pointer to an object. In theory, the object's
+reference count goes up by one when the variable is made to point to it and it
+goes down by one when the variable goes out of scope. However, these two
+cancel each other out, so at the end the reference count hasn't changed. The
+only real reason to use the reference count is to prevent the object from being
+deallocated as long as our variable is pointing to it. If we know that there
+is at least one other reference to the object that lives at least as long as
+our variable, there is no need to increment the reference count temporarily.
+An important situation where this arises is in objects that are passed as
+arguments to C functions in an extension module that are called from Python;
+the call mechanism guarantees to hold a reference to every argument for the
+duration of the call.
+
+However, a common pitfall is to extract an object from a list and hold on to it
+for a while without incrementing its reference count. Some other operation might
+conceivably remove the object from the list, decrementing its reference count
+and possible deallocating it. The real danger is that innocent-looking
+operations may invoke arbitrary Python code which could do this; there is a code
+path which allows control to flow back to the user from a :cfunc:`Py_DECREF`, so
+almost any operation is potentially dangerous.
+
+A safe approach is to always use the generic operations (functions whose name
+begins with ``PyObject_``, ``PyNumber_``, ``PySequence_`` or ``PyMapping_``).
+These operations always increment the reference count of the object they return.
+This leaves the caller with the responsibility to call :cfunc:`Py_DECREF` when
+they are done with the result; this soon becomes second nature.
+
+
+.. _api-refcountdetails:
+
+Reference Count Details
+^^^^^^^^^^^^^^^^^^^^^^^
+
+The reference count behavior of functions in the Python/C API is best explained
+in terms of *ownership of references*. Ownership pertains to references, never
+to objects (objects are not owned: they are always shared). "Owning a
+reference" means being responsible for calling Py_DECREF on it when the
+reference is no longer needed. Ownership can also be transferred, meaning that
+the code that receives ownership of the reference then becomes responsible for
+eventually decref'ing it by calling :cfunc:`Py_DECREF` or :cfunc:`Py_XDECREF`
+when it's no longer needed---or passing on this responsibility (usually to its
+caller). When a function passes ownership of a reference on to its caller, the
+caller is said to receive a *new* reference. When no ownership is transferred,
+the caller is said to *borrow* the reference. Nothing needs to be done for a
+borrowed reference.
+
+Conversely, when a calling function passes it a reference to an object, there
+are two possibilities: the function *steals* a reference to the object, or it
+does not. *Stealing a reference* means that when you pass a reference to a
+function, that function assumes that it now owns that reference, and you are not
+responsible for it any longer.
+
+.. index::
+ single: PyList_SetItem()
+ single: PyTuple_SetItem()
+
+Few functions steal references; the two notable exceptions are
+:cfunc:`PyList_SetItem` and :cfunc:`PyTuple_SetItem`, which steal a reference
+to the item (but not to the tuple or list into which the item is put!). These
+functions were designed to steal a reference because of a common idiom for
+populating a tuple or list with newly created objects; for example, the code to
+create the tuple ``(1, 2, "three")`` could look like this (forgetting about
+error handling for the moment; a better way to code this is shown below)::
+
+ PyObject *t;
+
+ t = PyTuple_New(3);
+ PyTuple_SetItem(t, 0, PyInt_FromLong(1L));
+ PyTuple_SetItem(t, 1, PyInt_FromLong(2L));
+ PyTuple_SetItem(t, 2, PyString_FromString("three"));
+
+Here, :cfunc:`PyInt_FromLong` returns a new reference which is immediately
+stolen by :cfunc:`PyTuple_SetItem`. When you want to keep using an object
+although the reference to it will be stolen, use :cfunc:`Py_INCREF` to grab
+another reference before calling the reference-stealing function.
+
+Incidentally, :cfunc:`PyTuple_SetItem` is the *only* way to set tuple items;
+:cfunc:`PySequence_SetItem` and :cfunc:`PyObject_SetItem` refuse to do this
+since tuples are an immutable data type. You should only use
+:cfunc:`PyTuple_SetItem` for tuples that you are creating yourself.
+
+Equivalent code for populating a list can be written using :cfunc:`PyList_New`
+and :cfunc:`PyList_SetItem`.
+
+However, in practice, you will rarely use these ways of creating and populating
+a tuple or list. There's a generic function, :cfunc:`Py_BuildValue`, that can
+create most common objects from C values, directed by a :dfn:`format string`.
+For example, the above two blocks of code could be replaced by the following
+(which also takes care of the error checking)::
+
+ PyObject *tuple, *list;
+
+ tuple = Py_BuildValue("(iis)", 1, 2, "three");
+ list = Py_BuildValue("[iis]", 1, 2, "three");
+
+It is much more common to use :cfunc:`PyObject_SetItem` and friends with items
+whose references you are only borrowing, like arguments that were passed in to
+the function you are writing. In that case, their behaviour regarding reference
+counts is much saner, since you don't have to increment a reference count so you
+can give a reference away ("have it be stolen"). For example, this function
+sets all items of a list (actually, any mutable sequence) to a given item::
+
+ int
+ set_all(PyObject *target, PyObject *item)
+ {
+ int i, n;
+
+ n = PyObject_Length(target);
+ if (n < 0)
+ return -1;
+ for (i = 0; i < n; i++) {
+ PyObject *index = PyInt_FromLong(i);
+ if (!index)
+ return -1;
+ if (PyObject_SetItem(target, index, item) < 0)
+ return -1;
+ Py_DECREF(index);
+ }
+ return 0;
+ }
+
+.. index:: single: set_all()
+
+The situation is slightly different for function return values. While passing
+a reference to most functions does not change your ownership responsibilities
+for that reference, many functions that return a reference to an object give
+you ownership of the reference. The reason is simple: in many cases, the
+returned object is created on the fly, and the reference you get is the only
+reference to the object. Therefore, the generic functions that return object
+references, like :cfunc:`PyObject_GetItem` and :cfunc:`PySequence_GetItem`,
+always return a new reference (the caller becomes the owner of the reference).
+
+It is important to realize that whether you own a reference returned by a
+function depends on which function you call only --- *the plumage* (the type of
+the object passed as an argument to the function) *doesn't enter into it!*
+Thus, if you extract an item from a list using :cfunc:`PyList_GetItem`, you
+don't own the reference --- but if you obtain the same item from the same list
+using :cfunc:`PySequence_GetItem` (which happens to take exactly the same
+arguments), you do own a reference to the returned object.
+
+.. index::
+ single: PyList_GetItem()
+ single: PySequence_GetItem()
+
+Here is an example of how you could write a function that computes the sum of
+the items in a list of integers; once using :cfunc:`PyList_GetItem`, and once
+using :cfunc:`PySequence_GetItem`. ::
+
+ long
+ sum_list(PyObject *list)
+ {
+ int i, n;
+ long total = 0;
+ PyObject *item;
+
+ n = PyList_Size(list);
+ if (n < 0)
+ return -1; /* Not a list */
+ for (i = 0; i < n; i++) {
+ item = PyList_GetItem(list, i); /* Can't fail */
+ if (!PyInt_Check(item)) continue; /* Skip non-integers */
+ total += PyInt_AsLong(item);
+ }
+ return total;
+ }
+
+.. index:: single: sum_list()
+
+::
+
+ long
+ sum_sequence(PyObject *sequence)
+ {
+ int i, n;
+ long total = 0;
+ PyObject *item;
+ n = PySequence_Length(sequence);
+ if (n < 0)
+ return -1; /* Has no length */
+ for (i = 0; i < n; i++) {
+ item = PySequence_GetItem(sequence, i);
+ if (item == NULL)
+ return -1; /* Not a sequence, or other failure */
+ if (PyInt_Check(item))
+ total += PyInt_AsLong(item);
+ Py_DECREF(item); /* Discard reference ownership */
+ }
+ return total;
+ }
+
+.. index:: single: sum_sequence()
+
+
+.. _api-types:
+
+Types
+-----
+
+There are few other data types that play a significant role in the Python/C
+API; most are simple C types such as :ctype:`int`, :ctype:`long`,
+:ctype:`double` and :ctype:`char\*`. A few structure types are used to
+describe static tables used to list the functions exported by a module or the
+data attributes of a new object type, and another is used to describe the value
+of a complex number. These will be discussed together with the functions that
+use them.
+
+
+.. _api-exceptions:
+
+Exceptions
+==========
+
+The Python programmer only needs to deal with exceptions if specific error
+handling is required; unhandled exceptions are automatically propagated to the
+caller, then to the caller's caller, and so on, until they reach the top-level
+interpreter, where they are reported to the user accompanied by a stack
+traceback.
+
+.. index:: single: PyErr_Occurred()
+
+For C programmers, however, error checking always has to be explicit. All
+functions in the Python/C API can raise exceptions, unless an explicit claim is
+made otherwise in a function's documentation. In general, when a function
+encounters an error, it sets an exception, discards any object references that
+it owns, and returns an error indicator --- usually *NULL* or ``-1``. A few
+functions return a Boolean true/false result, with false indicating an error.
+Very few functions return no explicit error indicator or have an ambiguous
+return value, and require explicit testing for errors with
+:cfunc:`PyErr_Occurred`.
+
+.. index::
+ single: PyErr_SetString()
+ single: PyErr_Clear()
+
+Exception state is maintained in per-thread storage (this is equivalent to
+using global storage in an unthreaded application). A thread can be in one of
+two states: an exception has occurred, or not. The function
+:cfunc:`PyErr_Occurred` can be used to check for this: it returns a borrowed
+reference to the exception type object when an exception has occurred, and
+*NULL* otherwise. There are a number of functions to set the exception state:
+:cfunc:`PyErr_SetString` is the most common (though not the most general)
+function to set the exception state, and :cfunc:`PyErr_Clear` clears the
+exception state.
+
+The full exception state consists of three objects (all of which can be
+*NULL*): the exception type, the corresponding exception value, and the
+traceback. These have the same meanings as the Python result of
+``sys.exc_info()``; however, they are not the same: the Python objects represent
+the last exception being handled by a Python :keyword:`try` ...
+:keyword:`except` statement, while the C level exception state only exists while
+an exception is being passed on between C functions until it reaches the Python
+bytecode interpreter's main loop, which takes care of transferring it to
+``sys.exc_info()`` and friends.
+
+.. index:: single: exc_info() (in module sys)
+
+Note that starting with Python 1.5, the preferred, thread-safe way to access the
+exception state from Python code is to call the function :func:`sys.exc_info`,
+which returns the per-thread exception state for Python code. Also, the
+semantics of both ways to access the exception state have changed so that a
+function which catches an exception will save and restore its thread's exception
+state so as to preserve the exception state of its caller. This prevents common
+bugs in exception handling code caused by an innocent-looking function
+overwriting the exception being handled; it also reduces the often unwanted
+lifetime extension for objects that are referenced by the stack frames in the
+traceback.
+
+As a general principle, a function that calls another function to perform some
+task should check whether the called function raised an exception, and if so,
+pass the exception state on to its caller. It should discard any object
+references that it owns, and return an error indicator, but it should *not* set
+another exception --- that would overwrite the exception that was just raised,
+and lose important information about the exact cause of the error.
+
+.. index:: single: sum_sequence()
+
+A simple example of detecting exceptions and passing them on is shown in the
+:cfunc:`sum_sequence` example above. It so happens that that example doesn't
+need to clean up any owned references when it detects an error. The following
+example function shows some error cleanup. First, to remind you why you like
+Python, we show the equivalent Python code::
+
+ def incr_item(dict, key):
+ try:
+ item = dict[key]
+ except KeyError:
+ item = 0
+ dict[key] = item + 1
+
+.. index:: single: incr_item()
+
+Here is the corresponding C code, in all its glory::
+
+ int
+ incr_item(PyObject *dict, PyObject *key)
+ {
+ /* Objects all initialized to NULL for Py_XDECREF */
+ PyObject *item = NULL, *const_one = NULL, *incremented_item = NULL;
+ int rv = -1; /* Return value initialized to -1 (failure) */
+
+ item = PyObject_GetItem(dict, key);
+ if (item == NULL) {
+ /* Handle KeyError only: */
+ if (!PyErr_ExceptionMatches(PyExc_KeyError))
+ goto error;
+
+ /* Clear the error and use zero: */
+ PyErr_Clear();
+ item = PyInt_FromLong(0L);
+ if (item == NULL)
+ goto error;
+ }
+ const_one = PyInt_FromLong(1L);
+ if (const_one == NULL)
+ goto error;
+
+ incremented_item = PyNumber_Add(item, const_one);
+ if (incremented_item == NULL)
+ goto error;
+
+ if (PyObject_SetItem(dict, key, incremented_item) < 0)
+ goto error;
+ rv = 0; /* Success */
+ /* Continue with cleanup code */
+
+ error:
+ /* Cleanup code, shared by success and failure path */
+
+ /* Use Py_XDECREF() to ignore NULL references */
+ Py_XDECREF(item);
+ Py_XDECREF(const_one);
+ Py_XDECREF(incremented_item);
+
+ return rv; /* -1 for error, 0 for success */
+ }
+
+.. index:: single: incr_item()
+
+.. index::
+ single: PyErr_ExceptionMatches()
+ single: PyErr_Clear()
+ single: Py_XDECREF()
+
+This example represents an endorsed use of the :keyword:`goto` statement in C!
+It illustrates the use of :cfunc:`PyErr_ExceptionMatches` and
+:cfunc:`PyErr_Clear` to handle specific exceptions, and the use of
+:cfunc:`Py_XDECREF` to dispose of owned references that may be *NULL* (note the
+``'X'`` in the name; :cfunc:`Py_DECREF` would crash when confronted with a
+*NULL* reference). It is important that the variables used to hold owned
+references are initialized to *NULL* for this to work; likewise, the proposed
+return value is initialized to ``-1`` (failure) and only set to success after
+the final call made is successful.
+
+
+.. _api-embedding:
+
+Embedding Python
+================
+
+The one important task that only embedders (as opposed to extension writers) of
+the Python interpreter have to worry about is the initialization, and possibly
+the finalization, of the Python interpreter. Most functionality of the
+interpreter can only be used after the interpreter has been initialized.
+
+.. index::
+ single: Py_Initialize()
+ module: __builtin__
+ module: __main__
+ module: sys
+ module: exceptions
+ triple: module; search; path
+ single: path (in module sys)
+
+The basic initialization function is :cfunc:`Py_Initialize`. This initializes
+the table of loaded modules, and creates the fundamental modules
+:mod:`__builtin__`, :mod:`__main__`, :mod:`sys`, and :mod:`exceptions`. It also
+initializes the module search path (``sys.path``).
+
+.. index:: single: PySys_SetArgv()
+
+:cfunc:`Py_Initialize` does not set the "script argument list" (``sys.argv``).
+If this variable is needed by Python code that will be executed later, it must
+be set explicitly with a call to ``PySys_SetArgv(argc, argv)`` subsequent to
+the call to :cfunc:`Py_Initialize`.
+
+On most systems (in particular, on Unix and Windows, although the details are
+slightly different), :cfunc:`Py_Initialize` calculates the module search path
+based upon its best guess for the location of the standard Python interpreter
+executable, assuming that the Python library is found in a fixed location
+relative to the Python interpreter executable. In particular, it looks for a
+directory named :file:`lib/python{X.Y}` relative to the parent directory
+where the executable named :file:`python` is found on the shell command search
+path (the environment variable :envvar:`PATH`).
+
+For instance, if the Python executable is found in
+:file:`/usr/local/bin/python`, it will assume that the libraries are in
+:file:`/usr/local/lib/python{X.Y}`. (In fact, this particular path is also
+the "fallback" location, used when no executable file named :file:`python` is
+found along :envvar:`PATH`.) The user can override this behavior by setting the
+environment variable :envvar:`PYTHONHOME`, or insert additional directories in
+front of the standard path by setting :envvar:`PYTHONPATH`.
+
+.. index::
+ single: Py_SetProgramName()
+ single: Py_GetPath()
+ single: Py_GetPrefix()
+ single: Py_GetExecPrefix()
+ single: Py_GetProgramFullPath()
+
+The embedding application can steer the search by calling
+``Py_SetProgramName(file)`` *before* calling :cfunc:`Py_Initialize`. Note that
+:envvar:`PYTHONHOME` still overrides this and :envvar:`PYTHONPATH` is still
+inserted in front of the standard path. An application that requires total
+control has to provide its own implementation of :cfunc:`Py_GetPath`,
+:cfunc:`Py_GetPrefix`, :cfunc:`Py_GetExecPrefix`, and
+:cfunc:`Py_GetProgramFullPath` (all defined in :file:`Modules/getpath.c`).
+
+.. index:: single: Py_IsInitialized()
+
+Sometimes, it is desirable to "uninitialize" Python. For instance, the
+application may want to start over (make another call to
+:cfunc:`Py_Initialize`) or the application is simply done with its use of
+Python and wants to free memory allocated by Python. This can be accomplished
+by calling :cfunc:`Py_Finalize`. The function :cfunc:`Py_IsInitialized` returns
+true if Python is currently in the initialized state. More information about
+these functions is given in a later chapter. Notice that :cfunc:`Py_Finalize`
+does *not* free all memory allocated by the Python interpreter, e.g. memory
+allocated by extension modules currently cannot be released.
+
+
+.. _api-debugging:
+
+Debugging Builds
+================
+
+Python can be built with several macros to enable extra checks of the
+interpreter and extension modules. These checks tend to add a large amount of
+overhead to the runtime so they are not enabled by default.
+
+A full list of the various types of debugging builds is in the file
+:file:`Misc/SpecialBuilds.txt` in the Python source distribution. Builds are
+available that support tracing of reference counts, debugging the memory
+allocator, or low-level profiling of the main interpreter loop. Only the most
+frequently-used builds will be described in the remainder of this section.
+
+Compiling the interpreter with the :cmacro:`Py_DEBUG` macro defined produces
+what is generally meant by "a debug build" of Python. :cmacro:`Py_DEBUG` is
+enabled in the Unix build by adding :option:`--with-pydebug` to the
+:file:`configure` command. It is also implied by the presence of the
+not-Python-specific :cmacro:`_DEBUG` macro. When :cmacro:`Py_DEBUG` is enabled
+in the Unix build, compiler optimization is disabled.
+
+In addition to the reference count debugging described below, the following
+extra checks are performed:
+
+* Extra checks are added to the object allocator.
+
+* Extra checks are added to the parser and compiler.
+
+* Downcasts from wide types to narrow types are checked for loss of information.
+
+* A number of assertions are added to the dictionary and set implementations.
+ In addition, the set object acquires a :meth:`test_c_api` method.
+
+* Sanity checks of the input arguments are added to frame creation.
+
+* The storage for long ints is initialized with a known invalid pattern to catch
+ reference to uninitialized digits.
+
+* Low-level tracing and extra exception checking are added to the runtime
+ virtual machine.
+
+* Extra checks are added to the memory arena implementation.
+
+* Extra debugging is added to the thread module.
+
+There may be additional checks not mentioned here.
+
+Defining :cmacro:`Py_TRACE_REFS` enables reference tracing. When defined, a
+circular doubly linked list of active objects is maintained by adding two extra
+fields to every :ctype:`PyObject`. Total allocations are tracked as well. Upon
+exit, all existing references are printed. (In interactive mode this happens
+after every statement run by the interpreter.) Implied by :cmacro:`Py_DEBUG`.
+
+Please refer to :file:`Misc/SpecialBuilds.txt` in the Python source distribution
+for more detailed information.
+
diff --git a/Doc/c-api/memory.rst b/Doc/c-api/memory.rst
new file mode 100644
index 0000000000..1dcb115838
--- /dev/null
+++ b/Doc/c-api/memory.rst
@@ -0,0 +1,207 @@
+.. highlightlang:: c
+
+
+.. _memory:
+
+*****************
+Memory Management
+*****************
+
+.. sectionauthor:: Vladimir Marangozov <Vladimir.Marangozov@inrialpes.fr>
+
+
+
+.. _memoryoverview:
+
+Overview
+========
+
+Memory management in Python involves a private heap containing all Python
+objects and data structures. The management of this private heap is ensured
+internally by the *Python memory manager*. The Python memory manager has
+different components which deal with various dynamic storage management aspects,
+like sharing, segmentation, preallocation or caching.
+
+At the lowest level, a raw memory allocator ensures that there is enough room in
+the private heap for storing all Python-related data by interacting with the
+memory manager of the operating system. On top of the raw memory allocator,
+several object-specific allocators operate on the same heap and implement
+distinct memory management policies adapted to the peculiarities of every object
+type. For example, integer objects are managed differently within the heap than
+strings, tuples or dictionaries because integers imply different storage
+requirements and speed/space tradeoffs. The Python memory manager thus delegates
+some of the work to the object-specific allocators, but ensures that the latter
+operate within the bounds of the private heap.
+
+It is important to understand that the management of the Python heap is
+performed by the interpreter itself and that the user has no control over it,
+even if she regularly manipulates object pointers to memory blocks inside that
+heap. The allocation of heap space for Python objects and other internal
+buffers is performed on demand by the Python memory manager through the Python/C
+API functions listed in this document.
+
+.. index::
+ single: malloc()
+ single: calloc()
+ single: realloc()
+ single: free()
+
+To avoid memory corruption, extension writers should never try to operate on
+Python objects with the functions exported by the C library: :cfunc:`malloc`,
+:cfunc:`calloc`, :cfunc:`realloc` and :cfunc:`free`. This will result in mixed
+calls between the C allocator and the Python memory manager with fatal
+consequences, because they implement different algorithms and operate on
+different heaps. However, one may safely allocate and release memory blocks
+with the C library allocator for individual purposes, as shown in the following
+example::
+
+ PyObject *res;
+ char *buf = (char *) malloc(BUFSIZ); /* for I/O */
+
+ if (buf == NULL)
+ return PyErr_NoMemory();
+ ...Do some I/O operation involving buf...
+ res = PyString_FromString(buf);
+ free(buf); /* malloc'ed */
+ return res;
+
+In this example, the memory request for the I/O buffer is handled by the C
+library allocator. The Python memory manager is involved only in the allocation
+of the string object returned as a result.
+
+In most situations, however, it is recommended to allocate memory from the
+Python heap specifically because the latter is under control of the Python
+memory manager. For example, this is required when the interpreter is extended
+with new object types written in C. Another reason for using the Python heap is
+the desire to *inform* the Python memory manager about the memory needs of the
+extension module. Even when the requested memory is used exclusively for
+internal, highly-specific purposes, delegating all memory requests to the Python
+memory manager causes the interpreter to have a more accurate image of its
+memory footprint as a whole. Consequently, under certain circumstances, the
+Python memory manager may or may not trigger appropriate actions, like garbage
+collection, memory compaction or other preventive procedures. Note that by using
+the C library allocator as shown in the previous example, the allocated memory
+for the I/O buffer escapes completely the Python memory manager.
+
+
+.. _memoryinterface:
+
+Memory Interface
+================
+
+The following function sets, modeled after the ANSI C standard, but specifying
+behavior when requesting zero bytes, are available for allocating and releasing
+memory from the Python heap:
+
+
+.. cfunction:: void* PyMem_Malloc(size_t n)
+
+ Allocates *n* bytes and returns a pointer of type :ctype:`void\*` to the
+ allocated memory, or *NULL* if the request fails. Requesting zero bytes returns
+ a distinct non-*NULL* pointer if possible, as if :cfunc:`PyMem_Malloc(1)` had
+ been called instead. The memory will not have been initialized in any way.
+
+
+.. cfunction:: void* PyMem_Realloc(void *p, size_t n)
+
+ Resizes the memory block pointed to by *p* to *n* bytes. The contents will be
+ unchanged to the minimum of the old and the new sizes. If *p* is *NULL*, the
+ call is equivalent to :cfunc:`PyMem_Malloc(n)`; else if *n* is equal to zero,
+ the memory block is resized but is not freed, and the returned pointer is
+ non-*NULL*. Unless *p* is *NULL*, it must have been returned by a previous call
+ to :cfunc:`PyMem_Malloc` or :cfunc:`PyMem_Realloc`. If the request fails,
+ :cfunc:`PyMem_Realloc` returns *NULL* and *p* remains a valid pointer to the
+ previous memory area.
+
+
+.. cfunction:: void PyMem_Free(void *p)
+
+ Frees the memory block pointed to by *p*, which must have been returned by a
+ previous call to :cfunc:`PyMem_Malloc` or :cfunc:`PyMem_Realloc`. Otherwise, or
+ if :cfunc:`PyMem_Free(p)` has been called before, undefined behavior occurs. If
+ *p* is *NULL*, no operation is performed.
+
+The following type-oriented macros are provided for convenience. Note that
+*TYPE* refers to any C type.
+
+
+.. cfunction:: TYPE* PyMem_New(TYPE, size_t n)
+
+ Same as :cfunc:`PyMem_Malloc`, but allocates ``(n * sizeof(TYPE))`` bytes of
+ memory. Returns a pointer cast to :ctype:`TYPE\*`. The memory will not have
+ been initialized in any way.
+
+
+.. cfunction:: TYPE* PyMem_Resize(void *p, TYPE, size_t n)
+
+ Same as :cfunc:`PyMem_Realloc`, but the memory block is resized to ``(n *
+ sizeof(TYPE))`` bytes. Returns a pointer cast to :ctype:`TYPE\*`. On return,
+ *p* will be a pointer to the new memory area, or *NULL* in the event of failure.
+
+
+.. cfunction:: void PyMem_Del(void *p)
+
+ Same as :cfunc:`PyMem_Free`.
+
+In addition, the following macro sets are provided for calling the Python memory
+allocator directly, without involving the C API functions listed above. However,
+note that their use does not preserve binary compatibility across Python
+versions and is therefore deprecated in extension modules.
+
+:cfunc:`PyMem_MALLOC`, :cfunc:`PyMem_REALLOC`, :cfunc:`PyMem_FREE`.
+
+:cfunc:`PyMem_NEW`, :cfunc:`PyMem_RESIZE`, :cfunc:`PyMem_DEL`.
+
+
+.. _memoryexamples:
+
+Examples
+========
+
+Here is the example from section :ref:`memoryoverview`, rewritten so that the
+I/O buffer is allocated from the Python heap by using the first function set::
+
+ PyObject *res;
+ char *buf = (char *) PyMem_Malloc(BUFSIZ); /* for I/O */
+
+ if (buf == NULL)
+ return PyErr_NoMemory();
+ /* ...Do some I/O operation involving buf... */
+ res = PyString_FromString(buf);
+ PyMem_Free(buf); /* allocated with PyMem_Malloc */
+ return res;
+
+The same code using the type-oriented function set::
+
+ PyObject *res;
+ char *buf = PyMem_New(char, BUFSIZ); /* for I/O */
+
+ if (buf == NULL)
+ return PyErr_NoMemory();
+ /* ...Do some I/O operation involving buf... */
+ res = PyString_FromString(buf);
+ PyMem_Del(buf); /* allocated with PyMem_New */
+ return res;
+
+Note that in the two examples above, the buffer is always manipulated via
+functions belonging to the same set. Indeed, it is required to use the same
+memory API family for a given memory block, so that the risk of mixing different
+allocators is reduced to a minimum. The following code sequence contains two
+errors, one of which is labeled as *fatal* because it mixes two different
+allocators operating on different heaps. ::
+
+ char *buf1 = PyMem_New(char, BUFSIZ);
+ char *buf2 = (char *) malloc(BUFSIZ);
+ char *buf3 = (char *) PyMem_Malloc(BUFSIZ);
+ ...
+ PyMem_Del(buf3); /* Wrong -- should be PyMem_Free() */
+ free(buf2); /* Right -- allocated via malloc() */
+ free(buf1); /* Fatal -- should be PyMem_Del() */
+
+In addition to the functions aimed at handling raw memory blocks from the Python
+heap, objects in Python are allocated and released with :cfunc:`PyObject_New`,
+:cfunc:`PyObject_NewVar` and :cfunc:`PyObject_Del`.
+
+These will be explained in the next chapter on defining and implementing new
+object types in C.
+
diff --git a/Doc/c-api/newtypes.rst b/Doc/c-api/newtypes.rst
new file mode 100644
index 0000000000..5933f99917
--- /dev/null
+++ b/Doc/c-api/newtypes.rst
@@ -0,0 +1,1740 @@
+.. highlightlang:: c
+
+
+.. _newtypes:
+
+*****************************
+Object Implementation Support
+*****************************
+
+This chapter describes the functions, types, and macros used when defining new
+object types.
+
+
+.. _allocating-objects:
+
+Allocating Objects on the Heap
+==============================
+
+
+.. cfunction:: PyObject* _PyObject_New(PyTypeObject *type)
+
+
+.. cfunction:: PyVarObject* _PyObject_NewVar(PyTypeObject *type, Py_ssize_t size)
+
+
+.. cfunction:: void _PyObject_Del(PyObject *op)
+
+
+.. cfunction:: PyObject* PyObject_Init(PyObject *op, PyTypeObject *type)
+
+ Initialize a newly-allocated object *op* with its type and initial reference.
+ Returns the initialized object. If *type* indicates that the object
+ participates in the cyclic garbage detector, it is added to the detector's set
+ of observed objects. Other fields of the object are not affected.
+
+
+.. cfunction:: PyVarObject* PyObject_InitVar(PyVarObject *op, PyTypeObject *type, Py_ssize_t size)
+
+ This does everything :cfunc:`PyObject_Init` does, and also initializes the
+ length information for a variable-size object.
+
+
+.. cfunction:: TYPE* PyObject_New(TYPE, PyTypeObject *type)
+
+ Allocate a new Python object using the C structure type *TYPE* and the Python
+ type object *type*. Fields not defined by the Python object header are not
+ initialized; the object's reference count will be one. The size of the memory
+ allocation is determined from the :attr:`tp_basicsize` field of the type object.
+
+
+.. cfunction:: TYPE* PyObject_NewVar(TYPE, PyTypeObject *type, Py_ssize_t size)
+
+ Allocate a new Python object using the C structure type *TYPE* and the Python
+ type object *type*. Fields not defined by the Python object header are not
+ initialized. The allocated memory allows for the *TYPE* structure plus *size*
+ fields of the size given by the :attr:`tp_itemsize` field of *type*. This is
+ useful for implementing objects like tuples, which are able to determine their
+ size at construction time. Embedding the array of fields into the same
+ allocation decreases the number of allocations, improving the memory management
+ efficiency.
+
+
+.. cfunction:: void PyObject_Del(PyObject *op)
+
+ Releases memory allocated to an object using :cfunc:`PyObject_New` or
+ :cfunc:`PyObject_NewVar`. This is normally called from the :attr:`tp_dealloc`
+ handler specified in the object's type. The fields of the object should not be
+ accessed after this call as the memory is no longer a valid Python object.
+
+
+.. cfunction:: PyObject* Py_InitModule(char *name, PyMethodDef *methods)
+
+ Create a new module object based on a name and table of functions, returning the
+ new module object.
+
+ .. versionchanged:: 2.3
+ Older versions of Python did not support *NULL* as the value for the *methods*
+ argument.
+
+
+.. cfunction:: PyObject* Py_InitModule3(char *name, PyMethodDef *methods, char *doc)
+
+ Create a new module object based on a name and table of functions, returning the
+ new module object. If *doc* is non-*NULL*, it will be used to define the
+ docstring for the module.
+
+ .. versionchanged:: 2.3
+ Older versions of Python did not support *NULL* as the value for the *methods*
+ argument.
+
+
+.. cfunction:: PyObject* Py_InitModule4(char *name, PyMethodDef *methods, char *doc, PyObject *self, int apiver)
+
+ Create a new module object based on a name and table of functions, returning the
+ new module object. If *doc* is non-*NULL*, it will be used to define the
+ docstring for the module. If *self* is non-*NULL*, it will passed to the
+ functions of the module as their (otherwise *NULL*) first parameter. (This was
+ added as an experimental feature, and there are no known uses in the current
+ version of Python.) For *apiver*, the only value which should be passed is
+ defined by the constant :const:`PYTHON_API_VERSION`.
+
+ .. note::
+
+ Most uses of this function should probably be using the :cfunc:`Py_InitModule3`
+ instead; only use this if you are sure you need it.
+
+ .. versionchanged:: 2.3
+ Older versions of Python did not support *NULL* as the value for the *methods*
+ argument.
+
+
+.. cvar:: PyObject _Py_NoneStruct
+
+ Object which is visible in Python as ``None``. This should only be accessed
+ using the ``Py_None`` macro, which evaluates to a pointer to this object.
+
+
+.. _common-structs:
+
+Common Object Structures
+========================
+
+There are a large number of structures which are used in the definition of
+object types for Python. This section describes these structures and how they
+are used.
+
+All Python objects ultimately share a small number of fields at the beginning of
+the object's representation in memory. These are represented by the
+:ctype:`PyObject` and :ctype:`PyVarObject` types, which are defined, in turn, by
+the expansions of some macros also used, whether directly or indirectly, in the
+definition of all other Python objects.
+
+
+.. ctype:: PyObject
+
+ All object types are extensions of this type. This is a type which contains the
+ information Python needs to treat a pointer to an object as an object. In a
+ normal "release" build, it contains only the objects reference count and a
+ pointer to the corresponding type object. It corresponds to the fields defined
+ by the expansion of the ``PyObject_HEAD`` macro.
+
+
+.. ctype:: PyVarObject
+
+ This is an extension of :ctype:`PyObject` that adds the :attr:`ob_size` field.
+ This is only used for objects that have some notion of *length*. This type does
+ not often appear in the Python/C API. It corresponds to the fields defined by
+ the expansion of the ``PyObject_VAR_HEAD`` macro.
+
+These macros are used in the definition of :ctype:`PyObject` and
+:ctype:`PyVarObject`:
+
+
+.. cmacro:: PyObject_HEAD
+
+ This is a macro which expands to the declarations of the fields of the
+ :ctype:`PyObject` type; it is used when declaring new types which represent
+ objects without a varying length. The specific fields it expands to depend on
+ the definition of :cmacro:`Py_TRACE_REFS`. By default, that macro is not
+ defined, and :cmacro:`PyObject_HEAD` expands to::
+
+ Py_ssize_t ob_refcnt;
+ PyTypeObject *ob_type;
+
+ When :cmacro:`Py_TRACE_REFS` is defined, it expands to::
+
+ PyObject *_ob_next, *_ob_prev;
+ Py_ssize_t ob_refcnt;
+ PyTypeObject *ob_type;
+
+
+.. cmacro:: PyObject_VAR_HEAD
+
+ This is a macro which expands to the declarations of the fields of the
+ :ctype:`PyVarObject` type; it is used when declaring new types which represent
+ objects with a length that varies from instance to instance. This macro always
+ expands to::
+
+ PyObject_HEAD
+ Py_ssize_t ob_size;
+
+ Note that :cmacro:`PyObject_HEAD` is part of the expansion, and that its own
+ expansion varies depending on the definition of :cmacro:`Py_TRACE_REFS`.
+
+PyObject_HEAD_INIT
+
+
+.. ctype:: PyCFunction
+
+ Type of the functions used to implement most Python callables in C. Functions of
+ this type take two :ctype:`PyObject\*` parameters and return one such value. If
+ the return value is *NULL*, an exception shall have been set. If not *NULL*,
+ the return value is interpreted as the return value of the function as exposed
+ in Python. The function must return a new reference.
+
+
+.. ctype:: PyMethodDef
+
+ Structure used to describe a method of an extension type. This structure has
+ four fields:
+
+ +------------------+-------------+-------------------------------+
+ | Field | C Type | Meaning |
+ +==================+=============+===============================+
+ | :attr:`ml_name` | char \* | name of the method |
+ +------------------+-------------+-------------------------------+
+ | :attr:`ml_meth` | PyCFunction | pointer to the C |
+ | | | implementation |
+ +------------------+-------------+-------------------------------+
+ | :attr:`ml_flags` | int | flag bits indicating how the |
+ | | | call should be constructed |
+ +------------------+-------------+-------------------------------+
+ | :attr:`ml_doc` | char \* | points to the contents of the |
+ | | | docstring |
+ +------------------+-------------+-------------------------------+
+
+The :attr:`ml_meth` is a C function pointer. The functions may be of different
+types, but they always return :ctype:`PyObject\*`. If the function is not of
+the :ctype:`PyCFunction`, the compiler will require a cast in the method table.
+Even though :ctype:`PyCFunction` defines the first parameter as
+:ctype:`PyObject\*`, it is common that the method implementation uses a the
+specific C type of the *self* object.
+
+The :attr:`ml_flags` field is a bitfield which can include the following flags.
+The individual flags indicate either a calling convention or a binding
+convention. Of the calling convention flags, only :const:`METH_VARARGS` and
+:const:`METH_KEYWORDS` can be combined (but note that :const:`METH_KEYWORDS`
+alone is equivalent to ``METH_VARARGS | METH_KEYWORDS``). Any of the calling
+convention flags can be combined with a binding flag.
+
+
+.. data:: METH_VARARGS
+
+ This is the typical calling convention, where the methods have the type
+ :ctype:`PyCFunction`. The function expects two :ctype:`PyObject\*` values. The
+ first one is the *self* object for methods; for module functions, it has the
+ value given to :cfunc:`Py_InitModule4` (or *NULL* if :cfunc:`Py_InitModule` was
+ used). The second parameter (often called *args*) is a tuple object
+ representing all arguments. This parameter is typically processed using
+ :cfunc:`PyArg_ParseTuple` or :cfunc:`PyArg_UnpackTuple`.
+
+
+.. data:: METH_KEYWORDS
+
+ Methods with these flags must be of type :ctype:`PyCFunctionWithKeywords`. The
+ function expects three parameters: *self*, *args*, and a dictionary of all the
+ keyword arguments. The flag is typically combined with :const:`METH_VARARGS`,
+ and the parameters are typically processed using
+ :cfunc:`PyArg_ParseTupleAndKeywords`.
+
+
+.. data:: METH_NOARGS
+
+ Methods without parameters don't need to check whether arguments are given if
+ they are listed with the :const:`METH_NOARGS` flag. They need to be of type
+ :ctype:`PyCFunction`. When used with object methods, the first parameter is
+ typically named ``self`` and will hold a reference to the object instance. In
+ all cases the second parameter will be *NULL*.
+
+
+.. data:: METH_O
+
+ Methods with a single object argument can be listed with the :const:`METH_O`
+ flag, instead of invoking :cfunc:`PyArg_ParseTuple` with a ``"O"`` argument.
+ They have the type :ctype:`PyCFunction`, with the *self* parameter, and a
+ :ctype:`PyObject\*` parameter representing the single argument.
+
+
+.. data:: METH_OLDARGS
+
+ This calling convention is deprecated. The method must be of type
+ :ctype:`PyCFunction`. The second argument is *NULL* if no arguments are given,
+ a single object if exactly one argument is given, and a tuple of objects if more
+ than one argument is given. There is no way for a function using this
+ convention to distinguish between a call with multiple arguments and a call with
+ a tuple as the only argument.
+
+These two constants are not used to indicate the calling convention but the
+binding when use with methods of classes. These may not be used for functions
+defined for modules. At most one of these flags may be set for any given
+method.
+
+
+.. data:: METH_CLASS
+
+ .. index:: builtin: classmethod
+
+ The method will be passed the type object as the first parameter rather than an
+ instance of the type. This is used to create *class methods*, similar to what
+ is created when using the :func:`classmethod` built-in function.
+
+ .. versionadded:: 2.3
+
+
+.. data:: METH_STATIC
+
+ .. index:: builtin: staticmethod
+
+ The method will be passed *NULL* as the first parameter rather than an instance
+ of the type. This is used to create *static methods*, similar to what is
+ created when using the :func:`staticmethod` built-in function.
+
+ .. versionadded:: 2.3
+
+One other constant controls whether a method is loaded in place of another
+definition with the same method name.
+
+
+.. data:: METH_COEXIST
+
+ The method will be loaded in place of existing definitions. Without
+ *METH_COEXIST*, the default is to skip repeated definitions. Since slot
+ wrappers are loaded before the method table, the existence of a *sq_contains*
+ slot, for example, would generate a wrapped method named :meth:`__contains__`
+ and preclude the loading of a corresponding PyCFunction with the same name.
+ With the flag defined, the PyCFunction will be loaded in place of the wrapper
+ object and will co-exist with the slot. This is helpful because calls to
+ PyCFunctions are optimized more than wrapper object calls.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: PyObject* Py_FindMethod(PyMethodDef table[], PyObject *ob, char *name)
+
+ Return a bound method object for an extension type implemented in C. This can
+ be useful in the implementation of a :attr:`tp_getattro` or :attr:`tp_getattr`
+ handler that does not use the :cfunc:`PyObject_GenericGetAttr` function.
+
+
+.. _type-structs:
+
+Type Objects
+============
+
+Perhaps one of the most important structures of the Python object system is the
+structure that defines a new type: the :ctype:`PyTypeObject` structure. Type
+objects can be handled using any of the :cfunc:`PyObject_\*` or
+:cfunc:`PyType_\*` functions, but do not offer much that's interesting to most
+Python applications. These objects are fundamental to how objects behave, so
+they are very important to the interpreter itself and to any extension module
+that implements new types.
+
+Type objects are fairly large compared to most of the standard types. The reason
+for the size is that each type object stores a large number of values, mostly C
+function pointers, each of which implements a small part of the type's
+functionality. The fields of the type object are examined in detail in this
+section. The fields will be described in the order in which they occur in the
+structure.
+
+Typedefs: unaryfunc, binaryfunc, ternaryfunc, inquiry, coercion, intargfunc,
+intintargfunc, intobjargproc, intintobjargproc, objobjargproc, destructor,
+freefunc, printfunc, getattrfunc, getattrofunc, setattrfunc, setattrofunc,
+cmpfunc, reprfunc, hashfunc
+
+The structure definition for :ctype:`PyTypeObject` can be found in
+:file:`Include/object.h`. For convenience of reference, this repeats the
+definition found there:
+
+.. literalinclude:: ../includes/typestruct.h
+
+
+The type object structure extends the :ctype:`PyVarObject` structure. The
+:attr:`ob_size` field is used for dynamic types (created by :func:`type_new`,
+usually called from a class statement). Note that :cdata:`PyType_Type` (the
+metatype) initializes :attr:`tp_itemsize`, which means that its instances (i.e.
+type objects) *must* have the :attr:`ob_size` field.
+
+
+.. cmember:: PyObject* PyObject._ob_next
+ PyObject* PyObject._ob_prev
+
+ These fields are only present when the macro ``Py_TRACE_REFS`` is defined.
+ Their initialization to *NULL* is taken care of by the ``PyObject_HEAD_INIT``
+ macro. For statically allocated objects, these fields always remain *NULL*.
+ For dynamically allocated objects, these two fields are used to link the object
+ into a doubly-linked list of *all* live objects on the heap. This could be used
+ for various debugging purposes; currently the only use is to print the objects
+ that are still alive at the end of a run when the environment variable
+ :envvar:`PYTHONDUMPREFS` is set.
+
+ These fields are not inherited by subtypes.
+
+
+.. cmember:: Py_ssize_t PyObject.ob_refcnt
+
+ This is the type object's reference count, initialized to ``1`` by the
+ ``PyObject_HEAD_INIT`` macro. Note that for statically allocated type objects,
+ the type's instances (objects whose :attr:`ob_type` points back to the type) do
+ *not* count as references. But for dynamically allocated type objects, the
+ instances *do* count as references.
+
+ This field is not inherited by subtypes.
+
+
+.. cmember:: PyTypeObject* PyObject.ob_type
+
+ This is the type's type, in other words its metatype. It is initialized by the
+ argument to the ``PyObject_HEAD_INIT`` macro, and its value should normally be
+ ``&PyType_Type``. However, for dynamically loadable extension modules that must
+ be usable on Windows (at least), the compiler complains that this is not a valid
+ initializer. Therefore, the convention is to pass *NULL* to the
+ ``PyObject_HEAD_INIT`` macro and to initialize this field explicitly at the
+ start of the module's initialization function, before doing anything else. This
+ is typically done like this::
+
+ Foo_Type.ob_type = &PyType_Type;
+
+ This should be done before any instances of the type are created.
+ :cfunc:`PyType_Ready` checks if :attr:`ob_type` is *NULL*, and if so,
+ initializes it: in Python 2.2, it is set to ``&PyType_Type``; in Python 2.2.1
+ and later it is initialized to the :attr:`ob_type` field of the base class.
+ :cfunc:`PyType_Ready` will not change this field if it is non-zero.
+
+ In Python 2.2, this field is not inherited by subtypes. In 2.2.1, and in 2.3
+ and beyond, it is inherited by subtypes.
+
+
+.. cmember:: Py_ssize_t PyVarObject.ob_size
+
+ For statically allocated type objects, this should be initialized to zero. For
+ dynamically allocated type objects, this field has a special internal meaning.
+
+ This field is not inherited by subtypes.
+
+
+.. cmember:: char* PyTypeObject.tp_name
+
+ Pointer to a NUL-terminated string containing the name of the type. For types
+ that are accessible as module globals, the string should be the full module
+ name, followed by a dot, followed by the type name; for built-in types, it
+ should be just the type name. If the module is a submodule of a package, the
+ full package name is part of the full module name. For example, a type named
+ :class:`T` defined in module :mod:`M` in subpackage :mod:`Q` in package :mod:`P`
+ should have the :attr:`tp_name` initializer ``"P.Q.M.T"``.
+
+ For dynamically allocated type objects, this should just be the type name, and
+ the module name explicitly stored in the type dict as the value for key
+ ``'__module__'``.
+
+ For statically allocated type objects, the tp_name field should contain a dot.
+ Everything before the last dot is made accessible as the :attr:`__module__`
+ attribute, and everything after the last dot is made accessible as the
+ :attr:`__name__` attribute.
+
+ If no dot is present, the entire :attr:`tp_name` field is made accessible as the
+ :attr:`__name__` attribute, and the :attr:`__module__` attribute is undefined
+ (unless explicitly set in the dictionary, as explained above). This means your
+ type will be impossible to pickle.
+
+ This field is not inherited by subtypes.
+
+
+.. cmember:: Py_ssize_t PyTypeObject.tp_basicsize
+ Py_ssize_t PyTypeObject.tp_itemsize
+
+ These fields allow calculating the size in bytes of instances of the type.
+
+ There are two kinds of types: types with fixed-length instances have a zero
+ :attr:`tp_itemsize` field, types with variable-length instances have a non-zero
+ :attr:`tp_itemsize` field. For a type with fixed-length instances, all
+ instances have the same size, given in :attr:`tp_basicsize`.
+
+ For a type with variable-length instances, the instances must have an
+ :attr:`ob_size` field, and the instance size is :attr:`tp_basicsize` plus N
+ times :attr:`tp_itemsize`, where N is the "length" of the object. The value of
+ N is typically stored in the instance's :attr:`ob_size` field. There are
+ exceptions: for example, long ints use a negative :attr:`ob_size` to indicate a
+ negative number, and N is ``abs(ob_size)`` there. Also, the presence of an
+ :attr:`ob_size` field in the instance layout doesn't mean that the instance
+ structure is variable-length (for example, the structure for the list type has
+ fixed-length instances, yet those instances have a meaningful :attr:`ob_size`
+ field).
+
+ The basic size includes the fields in the instance declared by the macro
+ :cmacro:`PyObject_HEAD` or :cmacro:`PyObject_VAR_HEAD` (whichever is used to
+ declare the instance struct) and this in turn includes the :attr:`_ob_prev` and
+ :attr:`_ob_next` fields if they are present. This means that the only correct
+ way to get an initializer for the :attr:`tp_basicsize` is to use the
+ :keyword:`sizeof` operator on the struct used to declare the instance layout.
+ The basic size does not include the GC header size (this is new in Python 2.2;
+ in 2.1 and 2.0, the GC header size was included in :attr:`tp_basicsize`).
+
+ These fields are inherited separately by subtypes. If the base type has a
+ non-zero :attr:`tp_itemsize`, it is generally not safe to set
+ :attr:`tp_itemsize` to a different non-zero value in a subtype (though this
+ depends on the implementation of the base type).
+
+ A note about alignment: if the variable items require a particular alignment,
+ this should be taken care of by the value of :attr:`tp_basicsize`. Example:
+ suppose a type implements an array of ``double``. :attr:`tp_itemsize` is
+ ``sizeof(double)``. It is the programmer's responsibility that
+ :attr:`tp_basicsize` is a multiple of ``sizeof(double)`` (assuming this is the
+ alignment requirement for ``double``).
+
+
+.. cmember:: destructor PyTypeObject.tp_dealloc
+
+ A pointer to the instance destructor function. This function must be defined
+ unless the type guarantees that its instances will never be deallocated (as is
+ the case for the singletons ``None`` and ``Ellipsis``).
+
+ The destructor function is called by the :cfunc:`Py_DECREF` and
+ :cfunc:`Py_XDECREF` macros when the new reference count is zero. At this point,
+ the instance is still in existence, but there are no references to it. The
+ destructor function should free all references which the instance owns, free all
+ memory buffers owned by the instance (using the freeing function corresponding
+ to the allocation function used to allocate the buffer), and finally (as its
+ last action) call the type's :attr:`tp_free` function. If the type is not
+ subtypable (doesn't have the :const:`Py_TPFLAGS_BASETYPE` flag bit set), it is
+ permissible to call the object deallocator directly instead of via
+ :attr:`tp_free`. The object deallocator should be the one used to allocate the
+ instance; this is normally :cfunc:`PyObject_Del` if the instance was allocated
+ using :cfunc:`PyObject_New` or :cfunc:`PyObject_VarNew`, or
+ :cfunc:`PyObject_GC_Del` if the instance was allocated using
+ :cfunc:`PyObject_GC_New` or :cfunc:`PyObject_GC_VarNew`.
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: printfunc PyTypeObject.tp_print
+
+ An optional pointer to the instance print function.
+
+ The print function is only called when the instance is printed to a *real* file;
+ when it is printed to a pseudo-file (like a :class:`StringIO` instance), the
+ instance's :attr:`tp_repr` or :attr:`tp_str` function is called to convert it to
+ a string. These are also called when the type's :attr:`tp_print` field is
+ *NULL*. A type should never implement :attr:`tp_print` in a way that produces
+ different output than :attr:`tp_repr` or :attr:`tp_str` would.
+
+ The print function is called with the same signature as :cfunc:`PyObject_Print`:
+ ``int tp_print(PyObject *self, FILE *file, int flags)``. The *self* argument is
+ the instance to be printed. The *file* argument is the stdio file to which it
+ is to be printed. The *flags* argument is composed of flag bits. The only flag
+ bit currently defined is :const:`Py_PRINT_RAW`. When the :const:`Py_PRINT_RAW`
+ flag bit is set, the instance should be printed the same way as :attr:`tp_str`
+ would format it; when the :const:`Py_PRINT_RAW` flag bit is clear, the instance
+ should be printed the same was as :attr:`tp_repr` would format it. It should
+ return ``-1`` and set an exception condition when an error occurred during the
+ comparison.
+
+ It is possible that the :attr:`tp_print` field will be deprecated. In any case,
+ it is recommended not to define :attr:`tp_print`, but instead to rely on
+ :attr:`tp_repr` and :attr:`tp_str` for printing.
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: getattrfunc PyTypeObject.tp_getattr
+
+ An optional pointer to the get-attribute-string function.
+
+ This field is deprecated. When it is defined, it should point to a function
+ that acts the same as the :attr:`tp_getattro` function, but taking a C string
+ instead of a Python string object to give the attribute name. The signature is
+ the same as for :cfunc:`PyObject_GetAttrString`.
+
+ This field is inherited by subtypes together with :attr:`tp_getattro`: a subtype
+ inherits both :attr:`tp_getattr` and :attr:`tp_getattro` from its base type when
+ the subtype's :attr:`tp_getattr` and :attr:`tp_getattro` are both *NULL*.
+
+
+.. cmember:: setattrfunc PyTypeObject.tp_setattr
+
+ An optional pointer to the set-attribute-string function.
+
+ This field is deprecated. When it is defined, it should point to a function
+ that acts the same as the :attr:`tp_setattro` function, but taking a C string
+ instead of a Python string object to give the attribute name. The signature is
+ the same as for :cfunc:`PyObject_SetAttrString`.
+
+ This field is inherited by subtypes together with :attr:`tp_setattro`: a subtype
+ inherits both :attr:`tp_setattr` and :attr:`tp_setattro` from its base type when
+ the subtype's :attr:`tp_setattr` and :attr:`tp_setattro` are both *NULL*.
+
+
+.. cmember:: cmpfunc PyTypeObject.tp_compare
+
+ An optional pointer to the three-way comparison function.
+
+ The signature is the same as for :cfunc:`PyObject_Compare`. The function should
+ return ``1`` if *self* greater than *other*, ``0`` if *self* is equal to
+ *other*, and ``-1`` if *self* less than *other*. It should return ``-1`` and
+ set an exception condition when an error occurred during the comparison.
+
+ This field is inherited by subtypes together with :attr:`tp_richcompare` and
+ :attr:`tp_hash`: a subtypes inherits all three of :attr:`tp_compare`,
+ :attr:`tp_richcompare`, and :attr:`tp_hash` when the subtype's
+ :attr:`tp_compare`, :attr:`tp_richcompare`, and :attr:`tp_hash` are all *NULL*.
+
+
+.. cmember:: reprfunc PyTypeObject.tp_repr
+
+ .. index:: builtin: repr
+
+ An optional pointer to a function that implements the built-in function
+ :func:`repr`.
+
+ The signature is the same as for :cfunc:`PyObject_Repr`; it must return a string
+ or a Unicode object. Ideally, this function should return a string that, when
+ passed to :func:`eval`, given a suitable environment, returns an object with the
+ same value. If this is not feasible, it should return a string starting with
+ ``'<'`` and ending with ``'>'`` from which both the type and the value of the
+ object can be deduced.
+
+ When this field is not set, a string of the form ``<%s object at %p>`` is
+ returned, where ``%s`` is replaced by the type name, and ``%p`` by the object's
+ memory address.
+
+ This field is inherited by subtypes.
+
+.. cmember:: PyNumberMethods *tp_as_number;
+
+ XXX
+
+.. cmember:: PySequenceMethods *tp_as_sequence;
+
+ XXX
+
+.. cmember:: PyMappingMethods *tp_as_mapping;
+
+ XXX
+
+
+.. cmember:: hashfunc PyTypeObject.tp_hash
+
+ .. index:: builtin: hash
+
+ An optional pointer to a function that implements the built-in function
+ :func:`hash`.
+
+ The signature is the same as for :cfunc:`PyObject_Hash`; it must return a C
+ long. The value ``-1`` should not be returned as a normal return value; when an
+ error occurs during the computation of the hash value, the function should set
+ an exception and return ``-1``.
+
+ When this field is not set, two possibilities exist: if the :attr:`tp_compare`
+ and :attr:`tp_richcompare` fields are both *NULL*, a default hash value based on
+ the object's address is returned; otherwise, a :exc:`TypeError` is raised.
+
+ This field is inherited by subtypes together with :attr:`tp_richcompare` and
+ :attr:`tp_compare`: a subtypes inherits all three of :attr:`tp_compare`,
+ :attr:`tp_richcompare`, and :attr:`tp_hash`, when the subtype's
+ :attr:`tp_compare`, :attr:`tp_richcompare` and :attr:`tp_hash` are all *NULL*.
+
+
+.. cmember:: ternaryfunc PyTypeObject.tp_call
+
+ An optional pointer to a function that implements calling the object. This
+ should be *NULL* if the object is not callable. The signature is the same as
+ for :cfunc:`PyObject_Call`.
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: reprfunc PyTypeObject.tp_str
+
+ An optional pointer to a function that implements the built-in operation
+ :func:`str`. (Note that :class:`str` is a type now, and :func:`str` calls the
+ constructor for that type. This constructor calls :cfunc:`PyObject_Str` to do
+ the actual work, and :cfunc:`PyObject_Str` will call this handler.)
+
+ The signature is the same as for :cfunc:`PyObject_Str`; it must return a string
+ or a Unicode object. This function should return a "friendly" string
+ representation of the object, as this is the representation that will be used by
+ the print statement.
+
+ When this field is not set, :cfunc:`PyObject_Repr` is called to return a string
+ representation.
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: getattrofunc PyTypeObject.tp_getattro
+
+ An optional pointer to the get-attribute function.
+
+ The signature is the same as for :cfunc:`PyObject_GetAttr`. It is usually
+ convenient to set this field to :cfunc:`PyObject_GenericGetAttr`, which
+ implements the normal way of looking for object attributes.
+
+ This field is inherited by subtypes together with :attr:`tp_getattr`: a subtype
+ inherits both :attr:`tp_getattr` and :attr:`tp_getattro` from its base type when
+ the subtype's :attr:`tp_getattr` and :attr:`tp_getattro` are both *NULL*.
+
+
+.. cmember:: setattrofunc PyTypeObject.tp_setattro
+
+ An optional pointer to the set-attribute function.
+
+ The signature is the same as for :cfunc:`PyObject_SetAttr`. It is usually
+ convenient to set this field to :cfunc:`PyObject_GenericSetAttr`, which
+ implements the normal way of setting object attributes.
+
+ This field is inherited by subtypes together with :attr:`tp_setattr`: a subtype
+ inherits both :attr:`tp_setattr` and :attr:`tp_setattro` from its base type when
+ the subtype's :attr:`tp_setattr` and :attr:`tp_setattro` are both *NULL*.
+
+
+.. cmember:: PyBufferProcs* PyTypeObject.tp_as_buffer
+
+ Pointer to an additional structure that contains fields relevant only to objects
+ which implement the buffer interface. These fields are documented in
+ :ref:`buffer-structs`.
+
+ The :attr:`tp_as_buffer` field is not inherited, but the contained fields are
+ inherited individually.
+
+
+.. cmember:: long PyTypeObject.tp_flags
+
+ This field is a bit mask of various flags. Some flags indicate variant
+ semantics for certain situations; others are used to indicate that certain
+ fields in the type object (or in the extension structures referenced via
+ :attr:`tp_as_number`, :attr:`tp_as_sequence`, :attr:`tp_as_mapping`, and
+ :attr:`tp_as_buffer`) that were historically not always present are valid; if
+ such a flag bit is clear, the type fields it guards must not be accessed and
+ must be considered to have a zero or *NULL* value instead.
+
+ Inheritance of this field is complicated. Most flag bits are inherited
+ individually, i.e. if the base type has a flag bit set, the subtype inherits
+ this flag bit. The flag bits that pertain to extension structures are strictly
+ inherited if the extension structure is inherited, i.e. the base type's value of
+ the flag bit is copied into the subtype together with a pointer to the extension
+ structure. The :const:`Py_TPFLAGS_HAVE_GC` flag bit is inherited together with
+ the :attr:`tp_traverse` and :attr:`tp_clear` fields, i.e. if the
+ :const:`Py_TPFLAGS_HAVE_GC` flag bit is clear in the subtype and the
+ :attr:`tp_traverse` and :attr:`tp_clear` fields in the subtype exist (as
+ indicated by the :const:`Py_TPFLAGS_HAVE_RICHCOMPARE` flag bit) and have *NULL*
+ values.
+
+ The following bit masks are currently defined; these can be or-ed together using
+ the ``|`` operator to form the value of the :attr:`tp_flags` field. The macro
+ :cfunc:`PyType_HasFeature` takes a type and a flags value, *tp* and *f*, and
+ checks whether ``tp->tp_flags & f`` is non-zero.
+
+
+ .. data:: Py_TPFLAGS_HAVE_GETCHARBUFFER
+
+ If this bit is set, the :ctype:`PyBufferProcs` struct referenced by
+ :attr:`tp_as_buffer` has the :attr:`bf_getcharbuffer` field.
+
+
+ .. data:: Py_TPFLAGS_HAVE_SEQUENCE_IN
+
+ If this bit is set, the :ctype:`PySequenceMethods` struct referenced by
+ :attr:`tp_as_sequence` has the :attr:`sq_contains` field.
+
+
+ .. data:: Py_TPFLAGS_GC
+
+ This bit is obsolete. The bit it used to name is no longer in use. The symbol
+ is now defined as zero.
+
+
+ .. data:: Py_TPFLAGS_HAVE_INPLACEOPS
+
+ If this bit is set, the :ctype:`PySequenceMethods` struct referenced by
+ :attr:`tp_as_sequence` and the :ctype:`PyNumberMethods` structure referenced by
+ :attr:`tp_as_number` contain the fields for in-place operators. In particular,
+ this means that the :ctype:`PyNumberMethods` structure has the fields
+ :attr:`nb_inplace_add`, :attr:`nb_inplace_subtract`,
+ :attr:`nb_inplace_multiply`, :attr:`nb_inplace_divide`,
+ :attr:`nb_inplace_remainder`, :attr:`nb_inplace_power`,
+ :attr:`nb_inplace_lshift`, :attr:`nb_inplace_rshift`, :attr:`nb_inplace_and`,
+ :attr:`nb_inplace_xor`, and :attr:`nb_inplace_or`; and the
+ :ctype:`PySequenceMethods` struct has the fields :attr:`sq_inplace_concat` and
+ :attr:`sq_inplace_repeat`.
+
+
+ .. data:: Py_TPFLAGS_CHECKTYPES
+
+ If this bit is set, the binary and ternary operations in the
+ :ctype:`PyNumberMethods` structure referenced by :attr:`tp_as_number` accept
+ arguments of arbitrary object types, and do their own type conversions if
+ needed. If this bit is clear, those operations require that all arguments have
+ the current type as their type, and the caller is supposed to perform a coercion
+ operation first. This applies to :attr:`nb_add`, :attr:`nb_subtract`,
+ :attr:`nb_multiply`, :attr:`nb_divide`, :attr:`nb_remainder`, :attr:`nb_divmod`,
+ :attr:`nb_power`, :attr:`nb_lshift`, :attr:`nb_rshift`, :attr:`nb_and`,
+ :attr:`nb_xor`, and :attr:`nb_or`.
+
+
+ .. data:: Py_TPFLAGS_HAVE_RICHCOMPARE
+
+ If this bit is set, the type object has the :attr:`tp_richcompare` field, as
+ well as the :attr:`tp_traverse` and the :attr:`tp_clear` fields.
+
+
+ .. data:: Py_TPFLAGS_HAVE_WEAKREFS
+
+ If this bit is set, the :attr:`tp_weaklistoffset` field is defined. Instances
+ of a type are weakly referenceable if the type's :attr:`tp_weaklistoffset` field
+ has a value greater than zero.
+
+
+ .. data:: Py_TPFLAGS_HAVE_ITER
+
+ If this bit is set, the type object has the :attr:`tp_iter` and
+ :attr:`tp_iternext` fields.
+
+
+ .. data:: Py_TPFLAGS_HAVE_CLASS
+
+ If this bit is set, the type object has several new fields defined starting in
+ Python 2.2: :attr:`tp_methods`, :attr:`tp_members`, :attr:`tp_getset`,
+ :attr:`tp_base`, :attr:`tp_dict`, :attr:`tp_descr_get`, :attr:`tp_descr_set`,
+ :attr:`tp_dictoffset`, :attr:`tp_init`, :attr:`tp_alloc`, :attr:`tp_new`,
+ :attr:`tp_free`, :attr:`tp_is_gc`, :attr:`tp_bases`, :attr:`tp_mro`,
+ :attr:`tp_cache`, :attr:`tp_subclasses`, and :attr:`tp_weaklist`.
+
+
+ .. data:: Py_TPFLAGS_HEAPTYPE
+
+ This bit is set when the type object itself is allocated on the heap. In this
+ case, the :attr:`ob_type` field of its instances is considered a reference to
+ the type, and the type object is INCREF'ed when a new instance is created, and
+ DECREF'ed when an instance is destroyed (this does not apply to instances of
+ subtypes; only the type referenced by the instance's ob_type gets INCREF'ed or
+ DECREF'ed).
+
+
+ .. data:: Py_TPFLAGS_BASETYPE
+
+ This bit is set when the type can be used as the base type of another type. If
+ this bit is clear, the type cannot be subtyped (similar to a "final" class in
+ Java).
+
+
+ .. data:: Py_TPFLAGS_READY
+
+ This bit is set when the type object has been fully initialized by
+ :cfunc:`PyType_Ready`.
+
+
+ .. data:: Py_TPFLAGS_READYING
+
+ This bit is set while :cfunc:`PyType_Ready` is in the process of initializing
+ the type object.
+
+
+ .. data:: Py_TPFLAGS_HAVE_GC
+
+ This bit is set when the object supports garbage collection. If this bit
+ is set, instances must be created using :cfunc:`PyObject_GC_New` and
+ destroyed using :cfunc:`PyObject_GC_Del`. More information in section
+ :ref:`supporting-cycle-detection`. This bit also implies that the
+ GC-related fields :attr:`tp_traverse` and :attr:`tp_clear` are present in
+ the type object; but those fields also exist when
+ :const:`Py_TPFLAGS_HAVE_GC` is clear but
+ :const:`Py_TPFLAGS_HAVE_RICHCOMPARE` is set.
+
+
+ .. data:: Py_TPFLAGS_DEFAULT
+
+ This is a bitmask of all the bits that pertain to the existence of certain
+ fields in the type object and its extension structures. Currently, it includes
+ the following bits: :const:`Py_TPFLAGS_HAVE_GETCHARBUFFER`,
+ :const:`Py_TPFLAGS_HAVE_SEQUENCE_IN`, :const:`Py_TPFLAGS_HAVE_INPLACEOPS`,
+ :const:`Py_TPFLAGS_HAVE_RICHCOMPARE`, :const:`Py_TPFLAGS_HAVE_WEAKREFS`,
+ :const:`Py_TPFLAGS_HAVE_ITER`, and :const:`Py_TPFLAGS_HAVE_CLASS`.
+
+
+.. cmember:: char* PyTypeObject.tp_doc
+
+ An optional pointer to a NUL-terminated C string giving the docstring for this
+ type object. This is exposed as the :attr:`__doc__` attribute on the type and
+ instances of the type.
+
+ This field is *not* inherited by subtypes.
+
+The following three fields only exist if the
+:const:`Py_TPFLAGS_HAVE_RICHCOMPARE` flag bit is set.
+
+
+.. cmember:: traverseproc PyTypeObject.tp_traverse
+
+ An optional pointer to a traversal function for the garbage collector. This is
+ only used if the :const:`Py_TPFLAGS_HAVE_GC` flag bit is set. More information
+ about Python's garbage collection scheme can be found in section
+ :ref:`supporting-cycle-detection`.
+
+ The :attr:`tp_traverse` pointer is used by the garbage collector to detect
+ reference cycles. A typical implementation of a :attr:`tp_traverse` function
+ simply calls :cfunc:`Py_VISIT` on each of the instance's members that are Python
+ objects. For exampe, this is function :cfunc:`local_traverse` from the
+ :mod:`thread` extension module::
+
+ static int
+ local_traverse(localobject *self, visitproc visit, void *arg)
+ {
+ Py_VISIT(self->args);
+ Py_VISIT(self->kw);
+ Py_VISIT(self->dict);
+ return 0;
+ }
+
+ Note that :cfunc:`Py_VISIT` is called only on those members that can participate
+ in reference cycles. Although there is also a ``self->key`` member, it can only
+ be *NULL* or a Python string and therefore cannot be part of a reference cycle.
+
+ On the other hand, even if you know a member can never be part of a cycle, as a
+ debugging aid you may want to visit it anyway just so the :mod:`gc` module's
+ :func:`get_referents` function will include it.
+
+ Note that :cfunc:`Py_VISIT` requires the *visit* and *arg* parameters to
+ :cfunc:`local_traverse` to have these specific names; don't name them just
+ anything.
+
+ This field is inherited by subtypes together with :attr:`tp_clear` and the
+ :const:`Py_TPFLAGS_HAVE_GC` flag bit: the flag bit, :attr:`tp_traverse`, and
+ :attr:`tp_clear` are all inherited from the base type if they are all zero in
+ the subtype *and* the subtype has the :const:`Py_TPFLAGS_HAVE_RICHCOMPARE` flag
+ bit set.
+
+
+.. cmember:: inquiry PyTypeObject.tp_clear
+
+ An optional pointer to a clear function for the garbage collector. This is only
+ used if the :const:`Py_TPFLAGS_HAVE_GC` flag bit is set.
+
+ The :attr:`tp_clear` member function is used to break reference cycles in cyclic
+ garbage detected by the garbage collector. Taken together, all :attr:`tp_clear`
+ functions in the system must combine to break all reference cycles. This is
+ subtle, and if in any doubt supply a :attr:`tp_clear` function. For example,
+ the tuple type does not implement a :attr:`tp_clear` function, because it's
+ possible to prove that no reference cycle can be composed entirely of tuples.
+ Therefore the :attr:`tp_clear` functions of other types must be sufficient to
+ break any cycle containing a tuple. This isn't immediately obvious, and there's
+ rarely a good reason to avoid implementing :attr:`tp_clear`.
+
+ Implementations of :attr:`tp_clear` should drop the instance's references to
+ those of its members that may be Python objects, and set its pointers to those
+ members to *NULL*, as in the following example::
+
+ static int
+ local_clear(localobject *self)
+ {
+ Py_CLEAR(self->key);
+ Py_CLEAR(self->args);
+ Py_CLEAR(self->kw);
+ Py_CLEAR(self->dict);
+ return 0;
+ }
+
+ The :cfunc:`Py_CLEAR` macro should be used, because clearing references is
+ delicate: the reference to the contained object must not be decremented until
+ after the pointer to the contained object is set to *NULL*. This is because
+ decrementing the reference count may cause the contained object to become trash,
+ triggering a chain of reclamation activity that may include invoking arbitrary
+ Python code (due to finalizers, or weakref callbacks, associated with the
+ contained object). If it's possible for such code to reference *self* again,
+ it's important that the pointer to the contained object be *NULL* at that time,
+ so that *self* knows the contained object can no longer be used. The
+ :cfunc:`Py_CLEAR` macro performs the operations in a safe order.
+
+ Because the goal of :attr:`tp_clear` functions is to break reference cycles,
+ it's not necessary to clear contained objects like Python strings or Python
+ integers, which can't participate in reference cycles. On the other hand, it may
+ be convenient to clear all contained Python objects, and write the type's
+ :attr:`tp_dealloc` function to invoke :attr:`tp_clear`.
+
+ More information about Python's garbage collection scheme can be found in
+ section :ref:`supporting-cycle-detection`.
+
+ This field is inherited by subtypes together with :attr:`tp_traverse` and the
+ :const:`Py_TPFLAGS_HAVE_GC` flag bit: the flag bit, :attr:`tp_traverse`, and
+ :attr:`tp_clear` are all inherited from the base type if they are all zero in
+ the subtype *and* the subtype has the :const:`Py_TPFLAGS_HAVE_RICHCOMPARE` flag
+ bit set.
+
+
+.. cmember:: richcmpfunc PyTypeObject.tp_richcompare
+
+ An optional pointer to the rich comparison function.
+
+ The signature is the same as for :cfunc:`PyObject_RichCompare`. The function
+ should return the result of the comparison (usually ``Py_True`` or
+ ``Py_False``). If the comparison is undefined, it must return
+ ``Py_NotImplemented``, if another error occurred it must return ``NULL`` and set
+ an exception condition.
+
+ This field is inherited by subtypes together with :attr:`tp_compare` and
+ :attr:`tp_hash`: a subtype inherits all three of :attr:`tp_compare`,
+ :attr:`tp_richcompare`, and :attr:`tp_hash`, when the subtype's
+ :attr:`tp_compare`, :attr:`tp_richcompare`, and :attr:`tp_hash` are all *NULL*.
+
+ The following constants are defined to be used as the third argument for
+ :attr:`tp_richcompare` and for :cfunc:`PyObject_RichCompare`:
+
+ +----------------+------------+
+ | Constant | Comparison |
+ +================+============+
+ | :const:`Py_LT` | ``<`` |
+ +----------------+------------+
+ | :const:`Py_LE` | ``<=`` |
+ +----------------+------------+
+ | :const:`Py_EQ` | ``==`` |
+ +----------------+------------+
+ | :const:`Py_NE` | ``!=`` |
+ +----------------+------------+
+ | :const:`Py_GT` | ``>`` |
+ +----------------+------------+
+ | :const:`Py_GE` | ``>=`` |
+ +----------------+------------+
+
+The next field only exists if the :const:`Py_TPFLAGS_HAVE_WEAKREFS` flag bit is
+set.
+
+
+.. cmember:: long PyTypeObject.tp_weaklistoffset
+
+ If the instances of this type are weakly referenceable, this field is greater
+ than zero and contains the offset in the instance structure of the weak
+ reference list head (ignoring the GC header, if present); this offset is used by
+ :cfunc:`PyObject_ClearWeakRefs` and the :cfunc:`PyWeakref_\*` functions. The
+ instance structure needs to include a field of type :ctype:`PyObject\*` which is
+ initialized to *NULL*.
+
+ Do not confuse this field with :attr:`tp_weaklist`; that is the list head for
+ weak references to the type object itself.
+
+ This field is inherited by subtypes, but see the rules listed below. A subtype
+ may override this offset; this means that the subtype uses a different weak
+ reference list head than the base type. Since the list head is always found via
+ :attr:`tp_weaklistoffset`, this should not be a problem.
+
+ When a type defined by a class statement has no :attr:`__slots__` declaration,
+ and none of its base types are weakly referenceable, the type is made weakly
+ referenceable by adding a weak reference list head slot to the instance layout
+ and setting the :attr:`tp_weaklistoffset` of that slot's offset.
+
+ When a type's :attr:`__slots__` declaration contains a slot named
+ :attr:`__weakref__`, that slot becomes the weak reference list head for
+ instances of the type, and the slot's offset is stored in the type's
+ :attr:`tp_weaklistoffset`.
+
+ When a type's :attr:`__slots__` declaration does not contain a slot named
+ :attr:`__weakref__`, the type inherits its :attr:`tp_weaklistoffset` from its
+ base type.
+
+The next two fields only exist if the :const:`Py_TPFLAGS_HAVE_CLASS` flag bit is
+set.
+
+
+.. cmember:: getiterfunc PyTypeObject.tp_iter
+
+ An optional pointer to a function that returns an iterator for the object. Its
+ presence normally signals that the instances of this type are iterable (although
+ sequences may be iterable without this function, and classic instances always
+ have this function, even if they don't define an :meth:`__iter__` method).
+
+ This function has the same signature as :cfunc:`PyObject_GetIter`.
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: iternextfunc PyTypeObject.tp_iternext
+
+ An optional pointer to a function that returns the next item in an iterator, or
+ raises :exc:`StopIteration` when the iterator is exhausted. Its presence
+ normally signals that the instances of this type are iterators (although classic
+ instances always have this function, even if they don't define a
+ :meth:`__next__` method).
+
+ Iterator types should also define the :attr:`tp_iter` function, and that
+ function should return the iterator instance itself (not a new iterator
+ instance).
+
+ This function has the same signature as :cfunc:`PyIter_Next`.
+
+ This field is inherited by subtypes.
+
+The next fields, up to and including :attr:`tp_weaklist`, only exist if the
+:const:`Py_TPFLAGS_HAVE_CLASS` flag bit is set.
+
+
+.. cmember:: struct PyMethodDef* PyTypeObject.tp_methods
+
+ An optional pointer to a static *NULL*-terminated array of :ctype:`PyMethodDef`
+ structures, declaring regular methods of this type.
+
+ For each entry in the array, an entry is added to the type's dictionary (see
+ :attr:`tp_dict` below) containing a method descriptor.
+
+ This field is not inherited by subtypes (methods are inherited through a
+ different mechanism).
+
+
+.. cmember:: struct PyMemberDef* PyTypeObject.tp_members
+
+ An optional pointer to a static *NULL*-terminated array of :ctype:`PyMemberDef`
+ structures, declaring regular data members (fields or slots) of instances of
+ this type.
+
+ For each entry in the array, an entry is added to the type's dictionary (see
+ :attr:`tp_dict` below) containing a member descriptor.
+
+ This field is not inherited by subtypes (members are inherited through a
+ different mechanism).
+
+
+.. cmember:: struct PyGetSetDef* PyTypeObject.tp_getset
+
+ An optional pointer to a static *NULL*-terminated array of :ctype:`PyGetSetDef`
+ structures, declaring computed attributes of instances of this type.
+
+ For each entry in the array, an entry is added to the type's dictionary (see
+ :attr:`tp_dict` below) containing a getset descriptor.
+
+ This field is not inherited by subtypes (computed attributes are inherited
+ through a different mechanism).
+
+ Docs for PyGetSetDef (XXX belong elsewhere)::
+
+ typedef PyObject *(*getter)(PyObject *, void *);
+ typedef int (*setter)(PyObject *, PyObject *, void *);
+
+ typedef struct PyGetSetDef {
+ char *name; /* attribute name */
+ getter get; /* C function to get the attribute */
+ setter set; /* C function to set the attribute */
+ char *doc; /* optional doc string */
+ void *closure; /* optional additional data for getter and setter */
+ } PyGetSetDef;
+
+
+.. cmember:: PyTypeObject* PyTypeObject.tp_base
+
+ An optional pointer to a base type from which type properties are inherited. At
+ this level, only single inheritance is supported; multiple inheritance require
+ dynamically creating a type object by calling the metatype.
+
+ This field is not inherited by subtypes (obviously), but it defaults to
+ ``&PyBaseObject_Type`` (which to Python programmers is known as the type
+ :class:`object`).
+
+
+.. cmember:: PyObject* PyTypeObject.tp_dict
+
+ The type's dictionary is stored here by :cfunc:`PyType_Ready`.
+
+ This field should normally be initialized to *NULL* before PyType_Ready is
+ called; it may also be initialized to a dictionary containing initial attributes
+ for the type. Once :cfunc:`PyType_Ready` has initialized the type, extra
+ attributes for the type may be added to this dictionary only if they don't
+ correspond to overloaded operations (like :meth:`__add__`).
+
+ This field is not inherited by subtypes (though the attributes defined in here
+ are inherited through a different mechanism).
+
+
+.. cmember:: descrgetfunc PyTypeObject.tp_descr_get
+
+ An optional pointer to a "descriptor get" function.
+
+ The function signature is ::
+
+ PyObject * tp_descr_get(PyObject *self, PyObject *obj, PyObject *type);
+
+ XXX blah, blah.
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: descrsetfunc PyTypeObject.tp_descr_set
+
+ An optional pointer to a "descriptor set" function.
+
+ The function signature is ::
+
+ int tp_descr_set(PyObject *self, PyObject *obj, PyObject *value);
+
+ This field is inherited by subtypes.
+
+ XXX blah, blah.
+
+
+.. cmember:: long PyTypeObject.tp_dictoffset
+
+ If the instances of this type have a dictionary containing instance variables,
+ this field is non-zero and contains the offset in the instances of the type of
+ the instance variable dictionary; this offset is used by
+ :cfunc:`PyObject_GenericGetAttr`.
+
+ Do not confuse this field with :attr:`tp_dict`; that is the dictionary for
+ attributes of the type object itself.
+
+ If the value of this field is greater than zero, it specifies the offset from
+ the start of the instance structure. If the value is less than zero, it
+ specifies the offset from the *end* of the instance structure. A negative
+ offset is more expensive to use, and should only be used when the instance
+ structure contains a variable-length part. This is used for example to add an
+ instance variable dictionary to subtypes of :class:`str` or :class:`tuple`. Note
+ that the :attr:`tp_basicsize` field should account for the dictionary added to
+ the end in that case, even though the dictionary is not included in the basic
+ object layout. On a system with a pointer size of 4 bytes,
+ :attr:`tp_dictoffset` should be set to ``-4`` to indicate that the dictionary is
+ at the very end of the structure.
+
+ The real dictionary offset in an instance can be computed from a negative
+ :attr:`tp_dictoffset` as follows::
+
+ dictoffset = tp_basicsize + abs(ob_size)*tp_itemsize + tp_dictoffset
+ if dictoffset is not aligned on sizeof(void*):
+ round up to sizeof(void*)
+
+ where :attr:`tp_basicsize`, :attr:`tp_itemsize` and :attr:`tp_dictoffset` are
+ taken from the type object, and :attr:`ob_size` is taken from the instance. The
+ absolute value is taken because long ints use the sign of :attr:`ob_size` to
+ store the sign of the number. (There's never a need to do this calculation
+ yourself; it is done for you by :cfunc:`_PyObject_GetDictPtr`.)
+
+ This field is inherited by subtypes, but see the rules listed below. A subtype
+ may override this offset; this means that the subtype instances store the
+ dictionary at a difference offset than the base type. Since the dictionary is
+ always found via :attr:`tp_dictoffset`, this should not be a problem.
+
+ When a type defined by a class statement has no :attr:`__slots__` declaration,
+ and none of its base types has an instance variable dictionary, a dictionary
+ slot is added to the instance layout and the :attr:`tp_dictoffset` is set to
+ that slot's offset.
+
+ When a type defined by a class statement has a :attr:`__slots__` declaration,
+ the type inherits its :attr:`tp_dictoffset` from its base type.
+
+ (Adding a slot named :attr:`__dict__` to the :attr:`__slots__` declaration does
+ not have the expected effect, it just causes confusion. Maybe this should be
+ added as a feature just like :attr:`__weakref__` though.)
+
+
+.. cmember:: initproc PyTypeObject.tp_init
+
+ An optional pointer to an instance initialization function.
+
+ This function corresponds to the :meth:`__init__` method of classes. Like
+ :meth:`__init__`, it is possible to create an instance without calling
+ :meth:`__init__`, and it is possible to reinitialize an instance by calling its
+ :meth:`__init__` method again.
+
+ The function signature is ::
+
+ int tp_init(PyObject *self, PyObject *args, PyObject *kwds)
+
+ The self argument is the instance to be initialized; the *args* and *kwds*
+ arguments represent positional and keyword arguments of the call to
+ :meth:`__init__`.
+
+ The :attr:`tp_init` function, if not *NULL*, is called when an instance is
+ created normally by calling its type, after the type's :attr:`tp_new` function
+ has returned an instance of the type. If the :attr:`tp_new` function returns an
+ instance of some other type that is not a subtype of the original type, no
+ :attr:`tp_init` function is called; if :attr:`tp_new` returns an instance of a
+ subtype of the original type, the subtype's :attr:`tp_init` is called. (VERSION
+ NOTE: described here is what is implemented in Python 2.2.1 and later. In
+ Python 2.2, the :attr:`tp_init` of the type of the object returned by
+ :attr:`tp_new` was always called, if not *NULL*.)
+
+ This field is inherited by subtypes.
+
+
+.. cmember:: allocfunc PyTypeObject.tp_alloc
+
+ An optional pointer to an instance allocation function.
+
+ The function signature is ::
+
+ PyObject *tp_alloc(PyTypeObject *self, Py_ssize_t nitems)
+
+ The purpose of this function is to separate memory allocation from memory
+ initialization. It should return a pointer to a block of memory of adequate
+ length for the instance, suitably aligned, and initialized to zeros, but with
+ :attr:`ob_refcnt` set to ``1`` and :attr:`ob_type` set to the type argument. If
+ the type's :attr:`tp_itemsize` is non-zero, the object's :attr:`ob_size` field
+ should be initialized to *nitems* and the length of the allocated memory block
+ should be ``tp_basicsize + nitems*tp_itemsize``, rounded up to a multiple of
+ ``sizeof(void*)``; otherwise, *nitems* is not used and the length of the block
+ should be :attr:`tp_basicsize`.
+
+ Do not use this function to do any other instance initialization, not even to
+ allocate additional memory; that should be done by :attr:`tp_new`.
+
+ This field is inherited by static subtypes, but not by dynamic subtypes
+ (subtypes created by a class statement); in the latter, this field is always set
+ to :cfunc:`PyType_GenericAlloc`, to force a standard heap allocation strategy.
+ That is also the recommended value for statically defined types.
+
+
+.. cmember:: newfunc PyTypeObject.tp_new
+
+ An optional pointer to an instance creation function.
+
+ If this function is *NULL* for a particular type, that type cannot be called to
+ create new instances; presumably there is some other way to create instances,
+ like a factory function.
+
+ The function signature is ::
+
+ PyObject *tp_new(PyTypeObject *subtype, PyObject *args, PyObject *kwds)
+
+ The subtype argument is the type of the object being created; the *args* and
+ *kwds* arguments represent positional and keyword arguments of the call to the
+ type. Note that subtype doesn't have to equal the type whose :attr:`tp_new`
+ function is called; it may be a subtype of that type (but not an unrelated
+ type).
+
+ The :attr:`tp_new` function should call ``subtype->tp_alloc(subtype, nitems)``
+ to allocate space for the object, and then do only as much further
+ initialization as is absolutely necessary. Initialization that can safely be
+ ignored or repeated should be placed in the :attr:`tp_init` handler. A good
+ rule of thumb is that for immutable types, all initialization should take place
+ in :attr:`tp_new`, while for mutable types, most initialization should be
+ deferred to :attr:`tp_init`.
+
+ This field is inherited by subtypes, except it is not inherited by static types
+ whose :attr:`tp_base` is *NULL* or ``&PyBaseObject_Type``. The latter exception
+ is a precaution so that old extension types don't become callable simply by
+ being linked with Python 2.2.
+
+
+.. cmember:: destructor PyTypeObject.tp_free
+
+ An optional pointer to an instance deallocation function.
+
+ The signature of this function has changed slightly: in Python 2.2 and 2.2.1,
+ its signature is :ctype:`destructor`::
+
+ void tp_free(PyObject *)
+
+ In Python 2.3 and beyond, its signature is :ctype:`freefunc`::
+
+ void tp_free(void *)
+
+ The only initializer that is compatible with both versions is ``_PyObject_Del``,
+ whose definition has suitably adapted in Python 2.3.
+
+ This field is inherited by static subtypes, but not by dynamic subtypes
+ (subtypes created by a class statement); in the latter, this field is set to a
+ deallocator suitable to match :cfunc:`PyType_GenericAlloc` and the value of the
+ :const:`Py_TPFLAGS_HAVE_GC` flag bit.
+
+
+.. cmember:: inquiry PyTypeObject.tp_is_gc
+
+ An optional pointer to a function called by the garbage collector.
+
+ The garbage collector needs to know whether a particular object is collectible
+ or not. Normally, it is sufficient to look at the object's type's
+ :attr:`tp_flags` field, and check the :const:`Py_TPFLAGS_HAVE_GC` flag bit. But
+ some types have a mixture of statically and dynamically allocated instances, and
+ the statically allocated instances are not collectible. Such types should
+ define this function; it should return ``1`` for a collectible instance, and
+ ``0`` for a non-collectible instance. The signature is ::
+
+ int tp_is_gc(PyObject *self)
+
+ (The only example of this are types themselves. The metatype,
+ :cdata:`PyType_Type`, defines this function to distinguish between statically
+ and dynamically allocated types.)
+
+ This field is inherited by subtypes. (VERSION NOTE: in Python 2.2, it was not
+ inherited. It is inherited in 2.2.1 and later versions.)
+
+
+.. cmember:: PyObject* PyTypeObject.tp_bases
+
+ Tuple of base types.
+
+ This is set for types created by a class statement. It should be *NULL* for
+ statically defined types.
+
+ This field is not inherited.
+
+
+.. cmember:: PyObject* PyTypeObject.tp_mro
+
+ Tuple containing the expanded set of base types, starting with the type itself
+ and ending with :class:`object`, in Method Resolution Order.
+
+ This field is not inherited; it is calculated fresh by :cfunc:`PyType_Ready`.
+
+
+.. cmember:: PyObject* PyTypeObject.tp_cache
+
+ Unused. Not inherited. Internal use only.
+
+
+.. cmember:: PyObject* PyTypeObject.tp_subclasses
+
+ List of weak references to subclasses. Not inherited. Internal use only.
+
+
+.. cmember:: PyObject* PyTypeObject.tp_weaklist
+
+ Weak reference list head, for weak references to this type object. Not
+ inherited. Internal use only.
+
+The remaining fields are only defined if the feature test macro
+:const:`COUNT_ALLOCS` is defined, and are for internal use only. They are
+documented here for completeness. None of these fields are inherited by
+subtypes.
+
+
+.. cmember:: Py_ssize_t PyTypeObject.tp_allocs
+
+ Number of allocations.
+
+
+.. cmember:: Py_ssize_t PyTypeObject.tp_frees
+
+ Number of frees.
+
+
+.. cmember:: Py_ssize_t PyTypeObject.tp_maxalloc
+
+ Maximum simultaneously allocated objects.
+
+
+.. cmember:: PyTypeObject* PyTypeObject.tp_next
+
+ Pointer to the next type object with a non-zero :attr:`tp_allocs` field.
+
+Also, note that, in a garbage collected Python, tp_dealloc may be called from
+any Python thread, not just the thread which created the object (if the object
+becomes part of a refcount cycle, that cycle might be collected by a garbage
+collection on any thread). This is not a problem for Python API calls, since
+the thread on which tp_dealloc is called will own the Global Interpreter Lock
+(GIL). However, if the object being destroyed in turn destroys objects from some
+other C or C++ library, care should be taken to ensure that destroying those
+objects on the thread which called tp_dealloc will not violate any assumptions
+of the library.
+
+
+.. _mapping-structs:
+
+Mapping Object Structures
+=========================
+
+
+.. ctype:: PyMappingMethods
+
+ Structure used to hold pointers to the functions used to implement the mapping
+ protocol for an extension type.
+
+
+.. _number-structs:
+
+Number Object Structures
+========================
+
+
+.. ctype:: PyNumberMethods
+
+ Structure used to hold pointers to the functions an extension type uses to
+ implement the number protocol.
+
+
+.. _sequence-structs:
+
+Sequence Object Structures
+==========================
+
+
+.. ctype:: PySequenceMethods
+
+ Structure used to hold pointers to the functions which an object uses to
+ implement the sequence protocol.
+
+
+.. _buffer-structs:
+
+Buffer Object Structures
+========================
+
+.. sectionauthor:: Greg J. Stein <greg@lyra.org>
+
+
+The buffer interface exports a model where an object can expose its internal
+data as a set of chunks of data, where each chunk is specified as a
+pointer/length pair. These chunks are called :dfn:`segments` and are presumed
+to be non-contiguous in memory.
+
+If an object does not export the buffer interface, then its :attr:`tp_as_buffer`
+member in the :ctype:`PyTypeObject` structure should be *NULL*. Otherwise, the
+:attr:`tp_as_buffer` will point to a :ctype:`PyBufferProcs` structure.
+
+.. note::
+
+ It is very important that your :ctype:`PyTypeObject` structure uses
+ :const:`Py_TPFLAGS_DEFAULT` for the value of the :attr:`tp_flags` member rather
+ than ``0``. This tells the Python runtime that your :ctype:`PyBufferProcs`
+ structure contains the :attr:`bf_getcharbuffer` slot. Older versions of Python
+ did not have this member, so a new Python interpreter using an old extension
+ needs to be able to test for its presence before using it.
+
+
+.. ctype:: PyBufferProcs
+
+ Structure used to hold the function pointers which define an implementation of
+ the buffer protocol.
+
+ The first slot is :attr:`bf_getreadbuffer`, of type :ctype:`getreadbufferproc`.
+ If this slot is *NULL*, then the object does not support reading from the
+ internal data. This is non-sensical, so implementors should fill this in, but
+ callers should test that the slot contains a non-*NULL* value.
+
+ The next slot is :attr:`bf_getwritebuffer` having type
+ :ctype:`getwritebufferproc`. This slot may be *NULL* if the object does not
+ allow writing into its returned buffers.
+
+ The third slot is :attr:`bf_getsegcount`, with type :ctype:`getsegcountproc`.
+ This slot must not be *NULL* and is used to inform the caller how many segments
+ the object contains. Simple objects such as :ctype:`PyString_Type` and
+ :ctype:`PyBuffer_Type` objects contain a single segment.
+
+ .. index:: single: PyType_HasFeature()
+
+ The last slot is :attr:`bf_getcharbuffer`, of type :ctype:`getcharbufferproc`.
+ This slot will only be present if the :const:`Py_TPFLAGS_HAVE_GETCHARBUFFER`
+ flag is present in the :attr:`tp_flags` field of the object's
+ :ctype:`PyTypeObject`. Before using this slot, the caller should test whether it
+ is present by using the :cfunc:`PyType_HasFeature` function. If the flag is
+ present, :attr:`bf_getcharbuffer` may be *NULL*, indicating that the object's
+ contents cannot be used as *8-bit characters*. The slot function may also raise
+ an error if the object's contents cannot be interpreted as 8-bit characters.
+ For example, if the object is an array which is configured to hold floating
+ point values, an exception may be raised if a caller attempts to use
+ :attr:`bf_getcharbuffer` to fetch a sequence of 8-bit characters. This notion of
+ exporting the internal buffers as "text" is used to distinguish between objects
+ that are binary in nature, and those which have character-based content.
+
+ .. note::
+
+ The current policy seems to state that these characters may be multi-byte
+ characters. This implies that a buffer size of *N* does not mean there are *N*
+ characters present.
+
+
+.. data:: Py_TPFLAGS_HAVE_GETCHARBUFFER
+
+ Flag bit set in the type structure to indicate that the :attr:`bf_getcharbuffer`
+ slot is known. This being set does not indicate that the object supports the
+ buffer interface or that the :attr:`bf_getcharbuffer` slot is non-*NULL*.
+
+
+.. ctype:: Py_ssize_t (*readbufferproc) (PyObject *self, Py_ssize_t segment, void **ptrptr)
+
+ Return a pointer to a readable segment of the buffer in ``*ptrptr``. This
+ function is allowed to raise an exception, in which case it must return ``-1``.
+ The *segment* which is specified must be zero or positive, and strictly less
+ than the number of segments returned by the :attr:`bf_getsegcount` slot
+ function. On success, it returns the length of the segment, and sets
+ ``*ptrptr`` to a pointer to that memory.
+
+
+.. ctype:: Py_ssize_t (*writebufferproc) (PyObject *self, Py_ssize_t segment, void **ptrptr)
+
+ Return a pointer to a writable memory buffer in ``*ptrptr``, and the length of
+ that segment as the function return value. The memory buffer must correspond to
+ buffer segment *segment*. Must return ``-1`` and set an exception on error.
+ :exc:`TypeError` should be raised if the object only supports read-only buffers,
+ and :exc:`SystemError` should be raised when *segment* specifies a segment that
+ doesn't exist.
+
+ .. % Why doesn't it raise ValueError for this one?
+ .. % GJS: because you shouldn't be calling it with an invalid
+ .. % segment. That indicates a blatant programming error in the C
+ .. % code.
+
+
+.. ctype:: Py_ssize_t (*segcountproc) (PyObject *self, Py_ssize_t *lenp)
+
+ Return the number of memory segments which comprise the buffer. If *lenp* is
+ not *NULL*, the implementation must report the sum of the sizes (in bytes) of
+ all segments in ``*lenp``. The function cannot fail.
+
+
+.. ctype:: Py_ssize_t (*charbufferproc) (PyObject *self, Py_ssize_t segment, const char **ptrptr)
+
+ Return the size of the segment *segment* that *ptrptr* is set to. ``*ptrptr``
+ is set to the memory buffer. Returns ``-1`` on error.
+
+
+.. _supporting-iteration:
+
+Supporting the Iterator Protocol
+================================
+
+
+.. _supporting-cycle-detection:
+
+Supporting Cyclic Garbage Collection
+====================================
+
+Python's support for detecting and collecting garbage which involves circular
+references requires support from object types which are "containers" for other
+objects which may also be containers. Types which do not store references to
+other objects, or which only store references to atomic types (such as numbers
+or strings), do not need to provide any explicit support for garbage collection.
+
+.. An example showing the use of these interfaces can be found in "Supporting the
+.. Cycle Collector (XXX not found: ../ext/example-cycle-support.html)".
+
+To create a container type, the :attr:`tp_flags` field of the type object must
+include the :const:`Py_TPFLAGS_HAVE_GC` and provide an implementation of the
+:attr:`tp_traverse` handler. If instances of the type are mutable, a
+:attr:`tp_clear` implementation must also be provided.
+
+
+.. data:: Py_TPFLAGS_HAVE_GC
+
+ Objects with a type with this flag set must conform with the rules documented
+ here. For convenience these objects will be referred to as container objects.
+
+Constructors for container types must conform to two rules:
+
+#. The memory for the object must be allocated using :cfunc:`PyObject_GC_New` or
+ :cfunc:`PyObject_GC_VarNew`.
+
+#. Once all the fields which may contain references to other containers are
+ initialized, it must call :cfunc:`PyObject_GC_Track`.
+
+
+.. cfunction:: TYPE* PyObject_GC_New(TYPE, PyTypeObject *type)
+
+ Analogous to :cfunc:`PyObject_New` but for container objects with the
+ :const:`Py_TPFLAGS_HAVE_GC` flag set.
+
+
+.. cfunction:: TYPE* PyObject_GC_NewVar(TYPE, PyTypeObject *type, Py_ssize_t size)
+
+ Analogous to :cfunc:`PyObject_NewVar` but for container objects with the
+ :const:`Py_TPFLAGS_HAVE_GC` flag set.
+
+
+.. cfunction:: PyVarObject * PyObject_GC_Resize(PyVarObject *op, Py_ssize_t)
+
+ Resize an object allocated by :cfunc:`PyObject_NewVar`. Returns the resized
+ object or *NULL* on failure.
+
+
+.. cfunction:: void PyObject_GC_Track(PyObject *op)
+
+ Adds the object *op* to the set of container objects tracked by the collector.
+ The collector can run at unexpected times so objects must be valid while being
+ tracked. This should be called once all the fields followed by the
+ :attr:`tp_traverse` handler become valid, usually near the end of the
+ constructor.
+
+
+.. cfunction:: void _PyObject_GC_TRACK(PyObject *op)
+
+ A macro version of :cfunc:`PyObject_GC_Track`. It should not be used for
+ extension modules.
+
+Similarly, the deallocator for the object must conform to a similar pair of
+rules:
+
+#. Before fields which refer to other containers are invalidated,
+ :cfunc:`PyObject_GC_UnTrack` must be called.
+
+#. The object's memory must be deallocated using :cfunc:`PyObject_GC_Del`.
+
+
+.. cfunction:: void PyObject_GC_Del(void *op)
+
+ Releases memory allocated to an object using :cfunc:`PyObject_GC_New` or
+ :cfunc:`PyObject_GC_NewVar`.
+
+
+.. cfunction:: void PyObject_GC_UnTrack(void *op)
+
+ Remove the object *op* from the set of container objects tracked by the
+ collector. Note that :cfunc:`PyObject_GC_Track` can be called again on this
+ object to add it back to the set of tracked objects. The deallocator
+ (:attr:`tp_dealloc` handler) should call this for the object before any of the
+ fields used by the :attr:`tp_traverse` handler become invalid.
+
+
+.. cfunction:: void _PyObject_GC_UNTRACK(PyObject *op)
+
+ A macro version of :cfunc:`PyObject_GC_UnTrack`. It should not be used for
+ extension modules.
+
+The :attr:`tp_traverse` handler accepts a function parameter of this type:
+
+
+.. ctype:: int (*visitproc)(PyObject *object, void *arg)
+
+ Type of the visitor function passed to the :attr:`tp_traverse` handler. The
+ function should be called with an object to traverse as *object* and the third
+ parameter to the :attr:`tp_traverse` handler as *arg*. The Python core uses
+ several visitor functions to implement cyclic garbage detection; it's not
+ expected that users will need to write their own visitor functions.
+
+The :attr:`tp_traverse` handler must have the following type:
+
+
+.. ctype:: int (*traverseproc)(PyObject *self, visitproc visit, void *arg)
+
+ Traversal function for a container object. Implementations must call the
+ *visit* function for each object directly contained by *self*, with the
+ parameters to *visit* being the contained object and the *arg* value passed to
+ the handler. The *visit* function must not be called with a *NULL* object
+ argument. If *visit* returns a non-zero value that value should be returned
+ immediately.
+
+To simplify writing :attr:`tp_traverse` handlers, a :cfunc:`Py_VISIT` macro is
+provided. In order to use this macro, the :attr:`tp_traverse` implementation
+must name its arguments exactly *visit* and *arg*:
+
+
+.. cfunction:: void Py_VISIT(PyObject *o)
+
+ Call the *visit* callback, with arguments *o* and *arg*. If *visit* returns a
+ non-zero value, then return it. Using this macro, :attr:`tp_traverse` handlers
+ look like::
+
+ static int
+ my_traverse(Noddy *self, visitproc visit, void *arg)
+ {
+ Py_VISIT(self->foo);
+ Py_VISIT(self->bar);
+ return 0;
+ }
+
+ .. versionadded:: 2.4
+
+The :attr:`tp_clear` handler must be of the :ctype:`inquiry` type, or *NULL* if
+the object is immutable.
+
+
+.. ctype:: int (*inquiry)(PyObject *self)
+
+ Drop references that may have created reference cycles. Immutable objects do
+ not have to define this method since they can never directly create reference
+ cycles. Note that the object must still be valid after calling this method
+ (don't just call :cfunc:`Py_DECREF` on a reference). The collector will call
+ this method if it detects that this object is involved in a reference cycle.
+
diff --git a/Doc/c-api/refcounting.rst b/Doc/c-api/refcounting.rst
new file mode 100644
index 0000000000..9dc357f0e1
--- /dev/null
+++ b/Doc/c-api/refcounting.rst
@@ -0,0 +1,74 @@
+.. highlightlang:: c
+
+
+.. _countingrefs:
+
+******************
+Reference Counting
+******************
+
+The macros in this section are used for managing reference counts of Python
+objects.
+
+
+.. cfunction:: void Py_INCREF(PyObject *o)
+
+ Increment the reference count for object *o*. The object must not be *NULL*; if
+ you aren't sure that it isn't *NULL*, use :cfunc:`Py_XINCREF`.
+
+
+.. cfunction:: void Py_XINCREF(PyObject *o)
+
+ Increment the reference count for object *o*. The object may be *NULL*, in
+ which case the macro has no effect.
+
+
+.. cfunction:: void Py_DECREF(PyObject *o)
+
+ Decrement the reference count for object *o*. The object must not be *NULL*; if
+ you aren't sure that it isn't *NULL*, use :cfunc:`Py_XDECREF`. If the reference
+ count reaches zero, the object's type's deallocation function (which must not be
+ *NULL*) is invoked.
+
+ .. warning::
+
+ The deallocation function can cause arbitrary Python code to be invoked (e.g.
+ when a class instance with a :meth:`__del__` method is deallocated). While
+ exceptions in such code are not propagated, the executed code has free access to
+ all Python global variables. This means that any object that is reachable from
+ a global variable should be in a consistent state before :cfunc:`Py_DECREF` is
+ invoked. For example, code to delete an object from a list should copy a
+ reference to the deleted object in a temporary variable, update the list data
+ structure, and then call :cfunc:`Py_DECREF` for the temporary variable.
+
+
+.. cfunction:: void Py_XDECREF(PyObject *o)
+
+ Decrement the reference count for object *o*. The object may be *NULL*, in
+ which case the macro has no effect; otherwise the effect is the same as for
+ :cfunc:`Py_DECREF`, and the same warning applies.
+
+
+.. cfunction:: void Py_CLEAR(PyObject *o)
+
+ Decrement the reference count for object *o*. The object may be *NULL*, in
+ which case the macro has no effect; otherwise the effect is the same as for
+ :cfunc:`Py_DECREF`, except that the argument is also set to *NULL*. The warning
+ for :cfunc:`Py_DECREF` does not apply with respect to the object passed because
+ the macro carefully uses a temporary variable and sets the argument to *NULL*
+ before decrementing its reference count.
+
+ It is a good idea to use this macro whenever decrementing the value of a
+ variable that might be traversed during garbage collection.
+
+ .. versionadded:: 2.4
+
+The following functions are for runtime dynamic embedding of Python:
+``Py_IncRef(PyObject \*o)``, `Py_DecRef(PyObject \*o)``. They are
+simply exported function versions of :cfunc:`Py_XINCREF` and
+:cfunc:`Py_XDECREF`, respectively.
+
+The following functions or macros are only for use within the interpreter core:
+:cfunc:`_Py_Dealloc`, :cfunc:`_Py_ForgetReference`, :cfunc:`_Py_NewReference`,
+as well as the global variable :cdata:`_Py_RefTotal`.
+
diff --git a/Doc/c-api/utilities.rst b/Doc/c-api/utilities.rst
new file mode 100644
index 0000000000..01c1ceb71a
--- /dev/null
+++ b/Doc/c-api/utilities.rst
@@ -0,0 +1,1030 @@
+.. highlightlang:: c
+
+
+.. _utilities:
+
+*********
+Utilities
+*********
+
+The functions in this chapter perform various utility tasks, ranging from
+helping C code be more portable across platforms, using Python modules from C,
+and parsing function arguments and constructing Python values from C values.
+
+
+.. _os:
+
+Operating System Utilities
+==========================
+
+
+.. cfunction:: int Py_FdIsInteractive(FILE *fp, const char *filename)
+
+ Return true (nonzero) if the standard I/O file *fp* with name *filename* is
+ deemed interactive. This is the case for files for which ``isatty(fileno(fp))``
+ is true. If the global flag :cdata:`Py_InteractiveFlag` is true, this function
+ also returns true if the *filename* pointer is *NULL* or if the name is equal to
+ one of the strings ``'<stdin>'`` or ``'???'``.
+
+
+.. cfunction:: long PyOS_GetLastModificationTime(char *filename)
+
+ Return the time of last modification of the file *filename*. The result is
+ encoded in the same way as the timestamp returned by the standard C library
+ function :cfunc:`time`.
+
+
+.. cfunction:: void PyOS_AfterFork()
+
+ Function to update some internal state after a process fork; this should be
+ called in the new process if the Python interpreter will continue to be used.
+ If a new executable is loaded into the new process, this function does not need
+ to be called.
+
+
+.. cfunction:: int PyOS_CheckStack()
+
+ Return true when the interpreter runs out of stack space. This is a reliable
+ check, but is only available when :const:`USE_STACKCHECK` is defined (currently
+ on Windows using the Microsoft Visual C++ compiler). :const:`USE_STACKCHECK`
+ will be defined automatically; you should never change the definition in your
+ own code.
+
+
+.. cfunction:: PyOS_sighandler_t PyOS_getsig(int i)
+
+ Return the current signal handler for signal *i*. This is a thin wrapper around
+ either :cfunc:`sigaction` or :cfunc:`signal`. Do not call those functions
+ directly! :ctype:`PyOS_sighandler_t` is a typedef alias for :ctype:`void
+ (\*)(int)`.
+
+
+.. cfunction:: PyOS_sighandler_t PyOS_setsig(int i, PyOS_sighandler_t h)
+
+ Set the signal handler for signal *i* to be *h*; return the old signal handler.
+ This is a thin wrapper around either :cfunc:`sigaction` or :cfunc:`signal`. Do
+ not call those functions directly! :ctype:`PyOS_sighandler_t` is a typedef
+ alias for :ctype:`void (\*)(int)`.
+
+
+.. _processcontrol:
+
+Process Control
+===============
+
+
+.. cfunction:: void Py_FatalError(const char *message)
+
+ .. index:: single: abort()
+
+ Print a fatal error message and kill the process. No cleanup is performed.
+ This function should only be invoked when a condition is detected that would
+ make it dangerous to continue using the Python interpreter; e.g., when the
+ object administration appears to be corrupted. On Unix, the standard C library
+ function :cfunc:`abort` is called which will attempt to produce a :file:`core`
+ file.
+
+
+.. cfunction:: void Py_Exit(int status)
+
+ .. index::
+ single: Py_Finalize()
+ single: exit()
+
+ Exit the current process. This calls :cfunc:`Py_Finalize` and then calls the
+ standard C library function ``exit(status)``.
+
+
+.. cfunction:: int Py_AtExit(void (*func) ())
+
+ .. index::
+ single: Py_Finalize()
+ single: cleanup functions
+
+ Register a cleanup function to be called by :cfunc:`Py_Finalize`. The cleanup
+ function will be called with no arguments and should return no value. At most
+ 32 cleanup functions can be registered. When the registration is successful,
+ :cfunc:`Py_AtExit` returns ``0``; on failure, it returns ``-1``. The cleanup
+ function registered last is called first. Each cleanup function will be called
+ at most once. Since Python's internal finalization will have completed before
+ the cleanup function, no Python APIs should be called by *func*.
+
+
+.. _importing:
+
+Importing Modules
+=================
+
+
+.. cfunction:: PyObject* PyImport_ImportModule(const char *name)
+
+ .. index::
+ single: package variable; __all__
+ single: __all__ (package variable)
+
+ This is a simplified interface to :cfunc:`PyImport_ImportModuleEx` below,
+ leaving the *globals* and *locals* arguments set to *NULL*. When the *name*
+ argument contains a dot (when it specifies a submodule of a package), the
+ *fromlist* argument is set to the list ``['*']`` so that the return value is the
+ named module rather than the top-level package containing it as would otherwise
+ be the case. (Unfortunately, this has an additional side effect when *name* in
+ fact specifies a subpackage instead of a submodule: the submodules specified in
+ the package's ``__all__`` variable are loaded.) Return a new reference to the
+ imported module, or *NULL* with an exception set on failure. Before Python 2.4,
+ the module may still be created in the failure case --- examine ``sys.modules``
+ to find out. Starting with Python 2.4, a failing import of a module no longer
+ leaves the module in ``sys.modules``.
+
+ .. versionchanged:: 2.4
+ failing imports remove incomplete module objects.
+
+ .. index:: single: modules (in module sys)
+
+
+.. cfunction:: PyObject* PyImport_ImportModuleEx(char *name, PyObject *globals, PyObject *locals, PyObject *fromlist)
+
+ .. index:: builtin: __import__
+
+ Import a module. This is best described by referring to the built-in Python
+ function :func:`__import__`, as the standard :func:`__import__` function calls
+ this function directly.
+
+ The return value is a new reference to the imported module or top-level package,
+ or *NULL* with an exception set on failure (before Python 2.4, the module may
+ still be created in this case). Like for :func:`__import__`, the return value
+ when a submodule of a package was requested is normally the top-level package,
+ unless a non-empty *fromlist* was given.
+
+ .. versionchanged:: 2.4
+ failing imports remove incomplete module objects.
+
+
+.. cfunction:: PyObject* PyImport_Import(PyObject *name)
+
+ .. index::
+ module: rexec
+ module: ihooks
+
+ This is a higher-level interface that calls the current "import hook function".
+ It invokes the :func:`__import__` function from the ``__builtins__`` of the
+ current globals. This means that the import is done using whatever import hooks
+ are installed in the current environment, e.g. by :mod:`rexec` or :mod:`ihooks`.
+
+
+.. cfunction:: PyObject* PyImport_ReloadModule(PyObject *m)
+
+ Reload a module. Return a new reference to the reloaded module, or *NULL* with
+ an exception set on failure (the module still exists in this case).
+
+
+.. cfunction:: PyObject* PyImport_AddModule(const char *name)
+
+ Return the module object corresponding to a module name. The *name* argument
+ may be of the form ``package.module``. First check the modules dictionary if
+ there's one there, and if not, create a new one and insert it in the modules
+ dictionary. Return *NULL* with an exception set on failure.
+
+ .. note::
+
+ This function does not load or import the module; if the module wasn't already
+ loaded, you will get an empty module object. Use :cfunc:`PyImport_ImportModule`
+ or one of its variants to import a module. Package structures implied by a
+ dotted name for *name* are not created if not already present.
+
+
+.. cfunction:: PyObject* PyImport_ExecCodeModule(char *name, PyObject *co)
+
+ .. index:: builtin: compile
+
+ Given a module name (possibly of the form ``package.module``) and a code object
+ read from a Python bytecode file or obtained from the built-in function
+ :func:`compile`, load the module. Return a new reference to the module object,
+ or *NULL* with an exception set if an error occurred. Before Python 2.4, the
+ module could still be created in error cases. Starting with Python 2.4, *name*
+ is removed from ``sys.modules`` in error cases, and even if *name* was already
+ in ``sys.modules`` on entry to :cfunc:`PyImport_ExecCodeModule`. Leaving
+ incompletely initialized modules in ``sys.modules`` is dangerous, as imports of
+ such modules have no way to know that the module object is an unknown (and
+ probably damaged with respect to the module author's intents) state.
+
+ This function will reload the module if it was already imported. See
+ :cfunc:`PyImport_ReloadModule` for the intended way to reload a module.
+
+ If *name* points to a dotted name of the form ``package.module``, any package
+ structures not already created will still not be created.
+
+ .. versionchanged:: 2.4
+ *name* is removed from ``sys.modules`` in error cases.
+
+
+.. cfunction:: long PyImport_GetMagicNumber()
+
+ Return the magic number for Python bytecode files (a.k.a. :file:`.pyc` and
+ :file:`.pyo` files). The magic number should be present in the first four bytes
+ of the bytecode file, in little-endian byte order.
+
+
+.. cfunction:: PyObject* PyImport_GetModuleDict()
+
+ Return the dictionary used for the module administration (a.k.a.
+ ``sys.modules``). Note that this is a per-interpreter variable.
+
+
+.. cfunction:: void _PyImport_Init()
+
+ Initialize the import mechanism. For internal use only.
+
+
+.. cfunction:: void PyImport_Cleanup()
+
+ Empty the module table. For internal use only.
+
+
+.. cfunction:: void _PyImport_Fini()
+
+ Finalize the import mechanism. For internal use only.
+
+
+.. cfunction:: PyObject* _PyImport_FindExtension(char *, char *)
+
+ For internal use only.
+
+
+.. cfunction:: PyObject* _PyImport_FixupExtension(char *, char *)
+
+ For internal use only.
+
+
+.. cfunction:: int PyImport_ImportFrozenModule(char *name)
+
+ Load a frozen module named *name*. Return ``1`` for success, ``0`` if the
+ module is not found, and ``-1`` with an exception set if the initialization
+ failed. To access the imported module on a successful load, use
+ :cfunc:`PyImport_ImportModule`. (Note the misnomer --- this function would
+ reload the module if it was already imported.)
+
+
+.. ctype:: struct _frozen
+
+ .. index:: single: freeze utility
+
+ This is the structure type definition for frozen module descriptors, as
+ generated by the :program:`freeze` utility (see :file:`Tools/freeze/` in the
+ Python source distribution). Its definition, found in :file:`Include/import.h`,
+ is::
+
+ struct _frozen {
+ char *name;
+ unsigned char *code;
+ int size;
+ };
+
+
+.. cvar:: struct _frozen* PyImport_FrozenModules
+
+ This pointer is initialized to point to an array of :ctype:`struct _frozen`
+ records, terminated by one whose members are all *NULL* or zero. When a frozen
+ module is imported, it is searched in this table. Third-party code could play
+ tricks with this to provide a dynamically created collection of frozen modules.
+
+
+.. cfunction:: int PyImport_AppendInittab(char *name, void (*initfunc)(void))
+
+ Add a single module to the existing table of built-in modules. This is a
+ convenience wrapper around :cfunc:`PyImport_ExtendInittab`, returning ``-1`` if
+ the table could not be extended. The new module can be imported by the name
+ *name*, and uses the function *initfunc* as the initialization function called
+ on the first attempted import. This should be called before
+ :cfunc:`Py_Initialize`.
+
+
+.. ctype:: struct _inittab
+
+ Structure describing a single entry in the list of built-in modules. Each of
+ these structures gives the name and initialization function for a module built
+ into the interpreter. Programs which embed Python may use an array of these
+ structures in conjunction with :cfunc:`PyImport_ExtendInittab` to provide
+ additional built-in modules. The structure is defined in
+ :file:`Include/import.h` as::
+
+ struct _inittab {
+ char *name;
+ void (*initfunc)(void);
+ };
+
+
+.. cfunction:: int PyImport_ExtendInittab(struct _inittab *newtab)
+
+ Add a collection of modules to the table of built-in modules. The *newtab*
+ array must end with a sentinel entry which contains *NULL* for the :attr:`name`
+ field; failure to provide the sentinel value can result in a memory fault.
+ Returns ``0`` on success or ``-1`` if insufficient memory could be allocated to
+ extend the internal table. In the event of failure, no modules are added to the
+ internal table. This should be called before :cfunc:`Py_Initialize`.
+
+
+.. _marshalling-utils:
+
+Data marshalling support
+========================
+
+These routines allow C code to work with serialized objects using the same data
+format as the :mod:`marshal` module. There are functions to write data into the
+serialization format, and additional functions that can be used to read the data
+back. Files used to store marshalled data must be opened in binary mode.
+
+Numeric values are stored with the least significant byte first.
+
+The module supports two versions of the data format: version 0 is the historical
+version, version 1 (new in Python 2.4) shares interned strings in the file, and
+upon unmarshalling. *Py_MARSHAL_VERSION* indicates the current file format
+(currently 1).
+
+
+.. cfunction:: void PyMarshal_WriteLongToFile(long value, FILE *file, int version)
+
+ Marshal a :ctype:`long` integer, *value*, to *file*. This will only write the
+ least-significant 32 bits of *value*; regardless of the size of the native
+ :ctype:`long` type.
+
+ .. versionchanged:: 2.4
+ *version* indicates the file format.
+
+
+.. cfunction:: void PyMarshal_WriteObjectToFile(PyObject *value, FILE *file, int version)
+
+ Marshal a Python object, *value*, to *file*.
+
+ .. versionchanged:: 2.4
+ *version* indicates the file format.
+
+
+.. cfunction:: PyObject* PyMarshal_WriteObjectToString(PyObject *value, int version)
+
+ Return a string object containing the marshalled representation of *value*.
+
+ .. versionchanged:: 2.4
+ *version* indicates the file format.
+
+
+The following functions allow marshalled values to be read back in.
+
+XXX What about error detection? It appears that reading past the end of the
+file will always result in a negative numeric value (where that's relevant), but
+it's not clear that negative values won't be handled properly when there's no
+error. What's the right way to tell? Should only non-negative values be written
+using these routines?
+
+
+.. cfunction:: long PyMarshal_ReadLongFromFile(FILE *file)
+
+ Return a C :ctype:`long` from the data stream in a :ctype:`FILE\*` opened for
+ reading. Only a 32-bit value can be read in using this function, regardless of
+ the native size of :ctype:`long`.
+
+
+.. cfunction:: int PyMarshal_ReadShortFromFile(FILE *file)
+
+ Return a C :ctype:`short` from the data stream in a :ctype:`FILE\*` opened for
+ reading. Only a 16-bit value can be read in using this function, regardless of
+ the native size of :ctype:`short`.
+
+
+.. cfunction:: PyObject* PyMarshal_ReadObjectFromFile(FILE *file)
+
+ Return a Python object from the data stream in a :ctype:`FILE\*` opened for
+ reading. On error, sets the appropriate exception (:exc:`EOFError` or
+ :exc:`TypeError`) and returns *NULL*.
+
+
+.. cfunction:: PyObject* PyMarshal_ReadLastObjectFromFile(FILE *file)
+
+ Return a Python object from the data stream in a :ctype:`FILE\*` opened for
+ reading. Unlike :cfunc:`PyMarshal_ReadObjectFromFile`, this function assumes
+ that no further objects will be read from the file, allowing it to aggressively
+ load file data into memory so that the de-serialization can operate from data in
+ memory rather than reading a byte at a time from the file. Only use these
+ variant if you are certain that you won't be reading anything else from the
+ file. On error, sets the appropriate exception (:exc:`EOFError` or
+ :exc:`TypeError`) and returns *NULL*.
+
+
+.. cfunction:: PyObject* PyMarshal_ReadObjectFromString(char *string, Py_ssize_t len)
+
+ Return a Python object from the data stream in a character buffer containing
+ *len* bytes pointed to by *string*. On error, sets the appropriate exception
+ (:exc:`EOFError` or :exc:`TypeError`) and returns *NULL*.
+
+
+.. _arg-parsing:
+
+Parsing arguments and building values
+=====================================
+
+These functions are useful when creating your own extensions functions and
+methods. Additional information and examples are available in
+:ref:`extending-index`.
+
+The first three of these functions described, :cfunc:`PyArg_ParseTuple`,
+:cfunc:`PyArg_ParseTupleAndKeywords`, and :cfunc:`PyArg_Parse`, all use *format
+strings* which are used to tell the function about the expected arguments. The
+format strings use the same syntax for each of these functions.
+
+A format string consists of zero or more "format units." A format unit
+describes one Python object; it is usually a single character or a parenthesized
+sequence of format units. With a few exceptions, a format unit that is not a
+parenthesized sequence normally corresponds to a single address argument to
+these functions. In the following description, the quoted form is the format
+unit; the entry in (round) parentheses is the Python object type that matches
+the format unit; and the entry in [square] brackets is the type of the C
+variable(s) whose address should be passed.
+
+``s`` (string or Unicode object) [const char \*]
+ Convert a Python string or Unicode object to a C pointer to a character string.
+ You must not provide storage for the string itself; a pointer to an existing
+ string is stored into the character pointer variable whose address you pass.
+ The C string is NUL-terminated. The Python string must not contain embedded NUL
+ bytes; if it does, a :exc:`TypeError` exception is raised. Unicode objects are
+ converted to C strings using the default encoding. If this conversion fails, a
+ :exc:`UnicodeError` is raised.
+
+``s#`` (string, Unicode or any read buffer compatible object) [const char \*, int]
+ This variant on ``s`` stores into two C variables, the first one a pointer to a
+ character string, the second one its length. In this case the Python string may
+ contain embedded null bytes. Unicode objects pass back a pointer to the default
+ encoded string version of the object if such a conversion is possible. All
+ other read-buffer compatible objects pass back a reference to the raw internal
+ data representation.
+
+``y`` (bytes object) [const char \*]
+ This variant on ``s`` convert a Python bytes object to a C pointer to a
+ character string. The bytes object must not contain embedded NUL bytes; if it
+ does, a :exc:`TypeError` exception is raised.
+
+``y#`` (bytes object) [const char \*, int]
+ This variant on ``s#`` stores into two C variables, the first one a pointer to a
+ character string, the second one its length. This only accepts bytes objects.
+
+``z`` (string or ``None``) [const char \*]
+ Like ``s``, but the Python object may also be ``None``, in which case the C
+ pointer is set to *NULL*.
+
+``z#`` (string or ``None`` or any read buffer compatible object) [const char \*, int]
+ This is to ``s#`` as ``z`` is to ``s``.
+
+``u`` (Unicode object) [Py_UNICODE \*]
+ Convert a Python Unicode object to a C pointer to a NUL-terminated buffer of
+ 16-bit Unicode (UTF-16) data. As with ``s``, there is no need to provide
+ storage for the Unicode data buffer; a pointer to the existing Unicode data is
+ stored into the :ctype:`Py_UNICODE` pointer variable whose address you pass.
+
+``u#`` (Unicode object) [Py_UNICODE \*, int]
+ This variant on ``u`` stores into two C variables, the first one a pointer to a
+ Unicode data buffer, the second one its length. Non-Unicode objects are handled
+ by interpreting their read-buffer pointer as pointer to a :ctype:`Py_UNICODE`
+ array.
+
+``es`` (string, Unicode object or character buffer compatible object) [const char \*encoding, char \*\*buffer]
+ This variant on ``s`` is used for encoding Unicode and objects convertible to
+ Unicode into a character buffer. It only works for encoded data without embedded
+ NUL bytes.
+
+ This format requires two arguments. The first is only used as input, and
+ must be a :ctype:`const char\*` which points to the name of an encoding as a
+ NUL-terminated string, or *NULL*, in which case the default encoding is used.
+ An exception is raised if the named encoding is not known to Python. The
+ second argument must be a :ctype:`char\*\*`; the value of the pointer it
+ references will be set to a buffer with the contents of the argument text.
+ The text will be encoded in the encoding specified by the first argument.
+
+ :cfunc:`PyArg_ParseTuple` will allocate a buffer of the needed size, copy the
+ encoded data into this buffer and adjust *\*buffer* to reference the newly
+ allocated storage. The caller is responsible for calling :cfunc:`PyMem_Free` to
+ free the allocated buffer after use.
+
+``et`` (string, Unicode object or character buffer compatible object) [const char \*encoding, char \*\*buffer]
+ Same as ``es`` except that 8-bit string objects are passed through without
+ recoding them. Instead, the implementation assumes that the string object uses
+ the encoding passed in as parameter.
+
+``es#`` (string, Unicode object or character buffer compatible object) [const char \*encoding, char \*\*buffer, int \*buffer_length]
+ This variant on ``s#`` is used for encoding Unicode and objects convertible to
+ Unicode into a character buffer. Unlike the ``es`` format, this variant allows
+ input data which contains NUL characters.
+
+ It requires three arguments. The first is only used as input, and must be a
+ :ctype:`const char\*` which points to the name of an encoding as a
+ NUL-terminated string, or *NULL*, in which case the default encoding is used.
+ An exception is raised if the named encoding is not known to Python. The
+ second argument must be a :ctype:`char\*\*`; the value of the pointer it
+ references will be set to a buffer with the contents of the argument text.
+ The text will be encoded in the encoding specified by the first argument.
+ The third argument must be a pointer to an integer; the referenced integer
+ will be set to the number of bytes in the output buffer.
+
+ There are two modes of operation:
+
+ If *\*buffer* points a *NULL* pointer, the function will allocate a buffer of
+ the needed size, copy the encoded data into this buffer and set *\*buffer* to
+ reference the newly allocated storage. The caller is responsible for calling
+ :cfunc:`PyMem_Free` to free the allocated buffer after usage.
+
+ If *\*buffer* points to a non-*NULL* pointer (an already allocated buffer),
+ :cfunc:`PyArg_ParseTuple` will use this location as the buffer and interpret the
+ initial value of *\*buffer_length* as the buffer size. It will then copy the
+ encoded data into the buffer and NUL-terminate it. If the buffer is not large
+ enough, a :exc:`ValueError` will be set.
+
+ In both cases, *\*buffer_length* is set to the length of the encoded data
+ without the trailing NUL byte.
+
+``et#`` (string, Unicode object or character buffer compatible object) [const char \*encoding, char \*\*buffer]
+ Same as ``es#`` except that string objects are passed through without recoding
+ them. Instead, the implementation assumes that the string object uses the
+ encoding passed in as parameter.
+
+``b`` (integer) [char]
+ Convert a Python integer to a tiny int, stored in a C :ctype:`char`.
+
+``B`` (integer) [unsigned char]
+ Convert a Python integer to a tiny int without overflow checking, stored in a C
+ :ctype:`unsigned char`.
+
+ .. versionadded:: 2.3
+
+``h`` (integer) [short int]
+ Convert a Python integer to a C :ctype:`short int`.
+
+``H`` (integer) [unsigned short int]
+ Convert a Python integer to a C :ctype:`unsigned short int`, without overflow
+ checking.
+
+ .. versionadded:: 2.3
+
+``i`` (integer) [int]
+ Convert a Python integer to a plain C :ctype:`int`.
+
+``I`` (integer) [unsigned int]
+ Convert a Python integer to a C :ctype:`unsigned int`, without overflow
+ checking.
+
+ .. versionadded:: 2.3
+
+``l`` (integer) [long int]
+ Convert a Python integer to a C :ctype:`long int`.
+
+``k`` (integer) [unsigned long]
+ Convert a Python integer or long integer to a C :ctype:`unsigned long` without
+ overflow checking.
+
+ .. versionadded:: 2.3
+
+``L`` (integer) [PY_LONG_LONG]
+ Convert a Python integer to a C :ctype:`long long`. This format is only
+ available on platforms that support :ctype:`long long` (or :ctype:`_int64` on
+ Windows).
+
+``K`` (integer) [unsigned PY_LONG_LONG]
+ Convert a Python integer or long integer to a C :ctype:`unsigned long long`
+ without overflow checking. This format is only available on platforms that
+ support :ctype:`unsigned long long` (or :ctype:`unsigned _int64` on Windows).
+
+ .. versionadded:: 2.3
+
+``n`` (integer) [Py_ssize_t]
+ Convert a Python integer or long integer to a C :ctype:`Py_ssize_t`.
+
+ .. versionadded:: 2.5
+
+``c`` (string of length 1) [char]
+ Convert a Python character, represented as a string of length 1, to a C
+ :ctype:`char`.
+
+``f`` (float) [float]
+ Convert a Python floating point number to a C :ctype:`float`.
+
+``d`` (float) [double]
+ Convert a Python floating point number to a C :ctype:`double`.
+
+``D`` (complex) [Py_complex]
+ Convert a Python complex number to a C :ctype:`Py_complex` structure.
+
+``O`` (object) [PyObject \*]
+ Store a Python object (without any conversion) in a C object pointer. The C
+ program thus receives the actual object that was passed. The object's reference
+ count is not increased. The pointer stored is not *NULL*.
+
+``O!`` (object) [*typeobject*, PyObject \*]
+ Store a Python object in a C object pointer. This is similar to ``O``, but
+ takes two C arguments: the first is the address of a Python type object, the
+ second is the address of the C variable (of type :ctype:`PyObject\*`) into which
+ the object pointer is stored. If the Python object does not have the required
+ type, :exc:`TypeError` is raised.
+
+``O&`` (object) [*converter*, *anything*]
+ Convert a Python object to a C variable through a *converter* function. This
+ takes two arguments: the first is a function, the second is the address of a C
+ variable (of arbitrary type), converted to :ctype:`void \*`. The *converter*
+ function in turn is called as follows::
+
+ status = converter(object, address);
+
+ where *object* is the Python object to be converted and *address* is the
+ :ctype:`void\*` argument that was passed to the :cfunc:`PyArg_Parse\*` function.
+ The returned *status* should be ``1`` for a successful conversion and ``0`` if
+ the conversion has failed. When the conversion fails, the *converter* function
+ should raise an exception.
+
+``S`` (string) [PyStringObject \*]
+ Like ``O`` but requires that the Python object is a string object. Raises
+ :exc:`TypeError` if the object is not a string object. The C variable may also
+ be declared as :ctype:`PyObject\*`.
+
+``U`` (Unicode string) [PyUnicodeObject \*]
+ Like ``O`` but requires that the Python object is a Unicode object. Raises
+ :exc:`TypeError` if the object is not a Unicode object. The C variable may also
+ be declared as :ctype:`PyObject\*`.
+
+``t#`` (read-only character buffer) [char \*, int]
+ Like ``s#``, but accepts any object which implements the read-only buffer
+ interface. The :ctype:`char\*` variable is set to point to the first byte of
+ the buffer, and the :ctype:`int` is set to the length of the buffer. Only
+ single-segment buffer objects are accepted; :exc:`TypeError` is raised for all
+ others.
+
+``w`` (read-write character buffer) [char \*]
+ Similar to ``s``, but accepts any object which implements the read-write buffer
+ interface. The caller must determine the length of the buffer by other means,
+ or use ``w#`` instead. Only single-segment buffer objects are accepted;
+ :exc:`TypeError` is raised for all others.
+
+``w#`` (read-write character buffer) [char \*, int]
+ Like ``s#``, but accepts any object which implements the read-write buffer
+ interface. The :ctype:`char \*` variable is set to point to the first byte of
+ the buffer, and the :ctype:`int` is set to the length of the buffer. Only
+ single-segment buffer objects are accepted; :exc:`TypeError` is raised for all
+ others.
+
+``(items)`` (tuple) [*matching-items*]
+ The object must be a Python sequence whose length is the number of format units
+ in *items*. The C arguments must correspond to the individual format units in
+ *items*. Format units for sequences may be nested.
+
+ .. note::
+
+ Prior to Python version 1.5.2, this format specifier only accepted a tuple
+ containing the individual parameters, not an arbitrary sequence. Code which
+ previously caused :exc:`TypeError` to be raised here may now proceed without an
+ exception. This is not expected to be a problem for existing code.
+
+It is possible to pass Python long integers where integers are requested;
+however no proper range checking is done --- the most significant bits are
+silently truncated when the receiving field is too small to receive the value
+(actually, the semantics are inherited from downcasts in C --- your mileage may
+vary).
+
+A few other characters have a meaning in a format string. These may not occur
+inside nested parentheses. They are:
+
+``|``
+ Indicates that the remaining arguments in the Python argument list are optional.
+ The C variables corresponding to optional arguments should be initialized to
+ their default value --- when an optional argument is not specified,
+ :cfunc:`PyArg_ParseTuple` does not touch the contents of the corresponding C
+ variable(s).
+
+``:``
+ The list of format units ends here; the string after the colon is used as the
+ function name in error messages (the "associated value" of the exception that
+ :cfunc:`PyArg_ParseTuple` raises).
+
+``;``
+ The list of format units ends here; the string after the semicolon is used as
+ the error message *instead* of the default error message. Clearly, ``:`` and
+ ``;`` mutually exclude each other.
+
+Note that any Python object references which are provided to the caller are
+*borrowed* references; do not decrement their reference count!
+
+Additional arguments passed to these functions must be addresses of variables
+whose type is determined by the format string; these are used to store values
+from the input tuple. There are a few cases, as described in the list of format
+units above, where these parameters are used as input values; they should match
+what is specified for the corresponding format unit in that case.
+
+For the conversion to succeed, the *arg* object must match the format and the
+format must be exhausted. On success, the :cfunc:`PyArg_Parse\*` functions
+return true, otherwise they return false and raise an appropriate exception.
+
+
+.. cfunction:: int PyArg_ParseTuple(PyObject *args, const char *format, ...)
+
+ Parse the parameters of a function that takes only positional parameters into
+ local variables. Returns true on success; on failure, it returns false and
+ raises the appropriate exception.
+
+
+.. cfunction:: int PyArg_VaParse(PyObject *args, const char *format, va_list vargs)
+
+ Identical to :cfunc:`PyArg_ParseTuple`, except that it accepts a va_list rather
+ than a variable number of arguments.
+
+
+.. cfunction:: int PyArg_ParseTupleAndKeywords(PyObject *args, PyObject *kw, const char *format, char *keywords[], ...)
+
+ Parse the parameters of a function that takes both positional and keyword
+ parameters into local variables. Returns true on success; on failure, it
+ returns false and raises the appropriate exception.
+
+
+.. cfunction:: int PyArg_VaParseTupleAndKeywords(PyObject *args, PyObject *kw, const char *format, char *keywords[], va_list vargs)
+
+ Identical to :cfunc:`PyArg_ParseTupleAndKeywords`, except that it accepts a
+ va_list rather than a variable number of arguments.
+
+
+.. cfunction:: int PyArg_Parse(PyObject *args, const char *format, ...)
+
+ Function used to deconstruct the argument lists of "old-style" functions ---
+ these are functions which use the :const:`METH_OLDARGS` parameter parsing
+ method. This is not recommended for use in parameter parsing in new code, and
+ most code in the standard interpreter has been modified to no longer use this
+ for that purpose. It does remain a convenient way to decompose other tuples,
+ however, and may continue to be used for that purpose.
+
+
+.. cfunction:: int PyArg_UnpackTuple(PyObject *args, const char *name, Py_ssize_t min, Py_ssize_t max, ...)
+
+ A simpler form of parameter retrieval which does not use a format string to
+ specify the types of the arguments. Functions which use this method to retrieve
+ their parameters should be declared as :const:`METH_VARARGS` in function or
+ method tables. The tuple containing the actual parameters should be passed as
+ *args*; it must actually be a tuple. The length of the tuple must be at least
+ *min* and no more than *max*; *min* and *max* may be equal. Additional
+ arguments must be passed to the function, each of which should be a pointer to a
+ :ctype:`PyObject\*` variable; these will be filled in with the values from
+ *args*; they will contain borrowed references. The variables which correspond
+ to optional parameters not given by *args* will not be filled in; these should
+ be initialized by the caller. This function returns true on success and false if
+ *args* is not a tuple or contains the wrong number of elements; an exception
+ will be set if there was a failure.
+
+ This is an example of the use of this function, taken from the sources for the
+ :mod:`_weakref` helper module for weak references::
+
+ static PyObject *
+ weakref_ref(PyObject *self, PyObject *args)
+ {
+ PyObject *object;
+ PyObject *callback = NULL;
+ PyObject *result = NULL;
+
+ if (PyArg_UnpackTuple(args, "ref", 1, 2, &object, &callback)) {
+ result = PyWeakref_NewRef(object, callback);
+ }
+ return result;
+ }
+
+ The call to :cfunc:`PyArg_UnpackTuple` in this example is entirely equivalent to
+ this call to :cfunc:`PyArg_ParseTuple`::
+
+ PyArg_ParseTuple(args, "O|O:ref", &object, &callback)
+
+ .. versionadded:: 2.2
+
+
+.. cfunction:: PyObject* Py_BuildValue(const char *format, ...)
+
+ Create a new value based on a format string similar to those accepted by the
+ :cfunc:`PyArg_Parse\*` family of functions and a sequence of values. Returns
+ the value or *NULL* in the case of an error; an exception will be raised if
+ *NULL* is returned.
+
+ :cfunc:`Py_BuildValue` does not always build a tuple. It builds a tuple only if
+ its format string contains two or more format units. If the format string is
+ empty, it returns ``None``; if it contains exactly one format unit, it returns
+ whatever object is described by that format unit. To force it to return a tuple
+ of size 0 or one, parenthesize the format string.
+
+ When memory buffers are passed as parameters to supply data to build objects, as
+ for the ``s`` and ``s#`` formats, the required data is copied. Buffers provided
+ by the caller are never referenced by the objects created by
+ :cfunc:`Py_BuildValue`. In other words, if your code invokes :cfunc:`malloc`
+ and passes the allocated memory to :cfunc:`Py_BuildValue`, your code is
+ responsible for calling :cfunc:`free` for that memory once
+ :cfunc:`Py_BuildValue` returns.
+
+ In the following description, the quoted form is the format unit; the entry in
+ (round) parentheses is the Python object type that the format unit will return;
+ and the entry in [square] brackets is the type of the C value(s) to be passed.
+
+ The characters space, tab, colon and comma are ignored in format strings (but
+ not within format units such as ``s#``). This can be used to make long format
+ strings a tad more readable.
+
+ ``s`` (string) [char \*]
+ Convert a null-terminated C string to a Python object. If the C string pointer
+ is *NULL*, ``None`` is used.
+
+ ``s#`` (string) [char \*, int]
+ Convert a C string and its length to a Python object. If the C string pointer
+ is *NULL*, the length is ignored and ``None`` is returned.
+
+ ``z`` (string or ``None``) [char \*]
+ Same as ``s``.
+
+ ``z#`` (string or ``None``) [char \*, int]
+ Same as ``s#``.
+
+ ``u`` (Unicode string) [Py_UNICODE \*]
+ Convert a null-terminated buffer of Unicode (UCS-2 or UCS-4) data to a Python
+ Unicode object. If the Unicode buffer pointer is *NULL*, ``None`` is returned.
+
+ ``u#`` (Unicode string) [Py_UNICODE \*, int]
+ Convert a Unicode (UCS-2 or UCS-4) data buffer and its length to a Python
+ Unicode object. If the Unicode buffer pointer is *NULL*, the length is ignored
+ and ``None`` is returned.
+
+ ``U`` (string) [char \*]
+ Convert a null-terminated C string to a Python unicode object. If the C string
+ pointer is *NULL*, ``None`` is used.
+
+ ``U#`` (string) [char \*, int]
+ Convert a C string and its length to a Python unicode object. If the C string
+ pointer is *NULL*, the length is ignored and ``None`` is returned.
+
+ ``i`` (integer) [int]
+ Convert a plain C :ctype:`int` to a Python integer object.
+
+ ``b`` (integer) [char]
+ Convert a plain C :ctype:`char` to a Python integer object.
+
+ ``h`` (integer) [short int]
+ Convert a plain C :ctype:`short int` to a Python integer object.
+
+ ``l`` (integer) [long int]
+ Convert a C :ctype:`long int` to a Python integer object.
+
+ ``B`` (integer) [unsigned char]
+ Convert a C :ctype:`unsigned char` to a Python integer object.
+
+ ``H`` (integer) [unsigned short int]
+ Convert a C :ctype:`unsigned short int` to a Python integer object.
+
+ ``I`` (integer/long) [unsigned int]
+ Convert a C :ctype:`unsigned int` to a Python integer object or a Python long
+ integer object, if it is larger than ``sys.maxint``.
+
+ ``k`` (integer/long) [unsigned long]
+ Convert a C :ctype:`unsigned long` to a Python integer object or a Python long
+ integer object, if it is larger than ``sys.maxint``.
+
+ ``L`` (long) [PY_LONG_LONG]
+ Convert a C :ctype:`long long` to a Python long integer object. Only available
+ on platforms that support :ctype:`long long`.
+
+ ``K`` (long) [unsigned PY_LONG_LONG]
+ Convert a C :ctype:`unsigned long long` to a Python long integer object. Only
+ available on platforms that support :ctype:`unsigned long long`.
+
+ ``n`` (int) [Py_ssize_t]
+ Convert a C :ctype:`Py_ssize_t` to a Python integer or long integer.
+
+ .. versionadded:: 2.5
+
+ ``c`` (string of length 1) [char]
+ Convert a C :ctype:`int` representing a character to a Python string of length
+ 1.
+
+ ``d`` (float) [double]
+ Convert a C :ctype:`double` to a Python floating point number.
+
+ ``f`` (float) [float]
+ Same as ``d``.
+
+ ``D`` (complex) [Py_complex \*]
+ Convert a C :ctype:`Py_complex` structure to a Python complex number.
+
+ ``O`` (object) [PyObject \*]
+ Pass a Python object untouched (except for its reference count, which is
+ incremented by one). If the object passed in is a *NULL* pointer, it is assumed
+ that this was caused because the call producing the argument found an error and
+ set an exception. Therefore, :cfunc:`Py_BuildValue` will return *NULL* but won't
+ raise an exception. If no exception has been raised yet, :exc:`SystemError` is
+ set.
+
+ ``S`` (object) [PyObject \*]
+ Same as ``O``.
+
+ ``N`` (object) [PyObject \*]
+ Same as ``O``, except it doesn't increment the reference count on the object.
+ Useful when the object is created by a call to an object constructor in the
+ argument list.
+
+ ``O&`` (object) [*converter*, *anything*]
+ Convert *anything* to a Python object through a *converter* function. The
+ function is called with *anything* (which should be compatible with :ctype:`void
+ \*`) as its argument and should return a "new" Python object, or *NULL* if an
+ error occurred.
+
+ ``(items)`` (tuple) [*matching-items*]
+ Convert a sequence of C values to a Python tuple with the same number of items.
+
+ ``[items]`` (list) [*matching-items*]
+ Convert a sequence of C values to a Python list with the same number of items.
+
+ ``{items}`` (dictionary) [*matching-items*]
+ Convert a sequence of C values to a Python dictionary. Each pair of consecutive
+ C values adds one item to the dictionary, serving as key and value,
+ respectively.
+
+ If there is an error in the format string, the :exc:`SystemError` exception is
+ set and *NULL* returned.
+
+
+.. _string-conversion:
+
+String conversion and formatting
+================================
+
+Functions for number conversion and formatted string output.
+
+
+.. cfunction:: int PyOS_snprintf(char *str, size_t size, const char *format, ...)
+
+ Output not more than *size* bytes to *str* according to the format string
+ *format* and the extra arguments. See the Unix man page :manpage:`snprintf(2)`.
+
+
+.. cfunction:: int PyOS_vsnprintf(char *str, size_t size, const char *format, va_list va)
+
+ Output not more than *size* bytes to *str* according to the format string
+ *format* and the variable argument list *va*. Unix man page
+ :manpage:`vsnprintf(2)`.
+
+:cfunc:`PyOS_snprintf` and :cfunc:`PyOS_vsnprintf` wrap the Standard C library
+functions :cfunc:`snprintf` and :cfunc:`vsnprintf`. Their purpose is to
+guarantee consistent behavior in corner cases, which the Standard C functions do
+not.
+
+The wrappers ensure that *str*[*size*-1] is always ``'\0'`` upon return. They
+never write more than *size* bytes (including the trailing ``'\0'``) into str.
+Both functions require that ``str != NULL``, ``size > 0`` and ``format !=
+NULL``.
+
+If the platform doesn't have :cfunc:`vsnprintf` and the buffer size needed to
+avoid truncation exceeds *size* by more than 512 bytes, Python aborts with a
+*Py_FatalError*.
+
+The return value (*rv*) for these functions should be interpreted as follows:
+
+* When ``0 <= rv < size``, the output conversion was successful and *rv*
+ characters were written to *str* (excluding the trailing ``'\0'`` byte at
+ *str*[*rv*]).
+
+* When ``rv >= size``, the output conversion was truncated and a buffer with
+ ``rv + 1`` bytes would have been needed to succeed. *str*[*size*-1] is ``'\0'``
+ in this case.
+
+* When ``rv < 0``, "something bad happened." *str*[*size*-1] is ``'\0'`` in
+ this case too, but the rest of *str* is undefined. The exact cause of the error
+ depends on the underlying platform.
+
+The following functions provide locale-independent string to number conversions.
+
+
+.. cfunction:: double PyOS_ascii_strtod(const char *nptr, char **endptr)
+
+ Convert a string to a :ctype:`double`. This function behaves like the Standard C
+ function :cfunc:`strtod` does in the C locale. It does this without changing the
+ current locale, since that would not be thread-safe.
+
+ :cfunc:`PyOS_ascii_strtod` should typically be used for reading configuration
+ files or other non-user input that should be locale independent.
+
+ .. versionadded:: 2.4
+
+ See the Unix man page :manpage:`strtod(2)` for details.
+
+
+.. cfunction:: char * PyOS_ascii_formatd(char *buffer, size_t buf_len, const char *format, double d)
+
+ Convert a :ctype:`double` to a string using the ``'.'`` as the decimal
+ separator. *format* is a :cfunc:`printf`\ -style format string specifying the
+ number format. Allowed conversion characters are ``'e'``, ``'E'``, ``'f'``,
+ ``'F'``, ``'g'`` and ``'G'``.
+
+ The return value is a pointer to *buffer* with the converted string or NULL if
+ the conversion failed.
+
+ .. versionadded:: 2.4
+
+
+.. cfunction:: double PyOS_ascii_atof(const char *nptr)
+
+ Convert a string to a :ctype:`double` in a locale-independent way.
+
+ .. versionadded:: 2.4
+
+ See the Unix man page :manpage:`atof(2)` for details.
+
diff --git a/Doc/c-api/veryhigh.rst b/Doc/c-api/veryhigh.rst
new file mode 100644
index 0000000000..4b26da6ac2
--- /dev/null
+++ b/Doc/c-api/veryhigh.rst
@@ -0,0 +1,278 @@
+.. highlightlang:: c
+
+
+.. _veryhigh:
+
+*************************
+The Very High Level Layer
+*************************
+
+The functions in this chapter will let you execute Python source code given in a
+file or a buffer, but they will not let you interact in a more detailed way with
+the interpreter.
+
+Several of these functions accept a start symbol from the grammar as a
+parameter. The available start symbols are :const:`Py_eval_input`,
+:const:`Py_file_input`, and :const:`Py_single_input`. These are described
+following the functions which accept them as parameters.
+
+Note also that several of these functions take :ctype:`FILE\*` parameters. On
+particular issue which needs to be handled carefully is that the :ctype:`FILE`
+structure for different C libraries can be different and incompatible. Under
+Windows (at least), it is possible for dynamically linked extensions to actually
+use different libraries, so care should be taken that :ctype:`FILE\*` parameters
+are only passed to these functions if it is certain that they were created by
+the same library that the Python runtime is using.
+
+
+.. cfunction:: int Py_Main(int argc, char **argv)
+
+ The main program for the standard interpreter. This is made available for
+ programs which embed Python. The *argc* and *argv* parameters should be
+ prepared exactly as those which are passed to a C program's :cfunc:`main`
+ function. It is important to note that the argument list may be modified (but
+ the contents of the strings pointed to by the argument list are not). The return
+ value will be the integer passed to the :func:`sys.exit` function, ``1`` if the
+ interpreter exits due to an exception, or ``2`` if the parameter list does not
+ represent a valid Python command line.
+
+
+.. cfunction:: int PyRun_AnyFile(FILE *fp, const char *filename)
+
+ This is a simplified interface to :cfunc:`PyRun_AnyFileExFlags` below, leaving
+ *closeit* set to ``0`` and *flags* set to *NULL*.
+
+
+.. cfunction:: int PyRun_AnyFileFlags(FILE *fp, const char *filename, PyCompilerFlags *flags)
+
+ This is a simplified interface to :cfunc:`PyRun_AnyFileExFlags` below, leaving
+ the *closeit* argument set to ``0``.
+
+
+.. cfunction:: int PyRun_AnyFileEx(FILE *fp, const char *filename, int closeit)
+
+ This is a simplified interface to :cfunc:`PyRun_AnyFileExFlags` below, leaving
+ the *flags* argument set to *NULL*.
+
+
+.. cfunction:: int PyRun_AnyFileExFlags(FILE *fp, const char *filename, int closeit, PyCompilerFlags *flags)
+
+ If *fp* refers to a file associated with an interactive device (console or
+ terminal input or Unix pseudo-terminal), return the value of
+ :cfunc:`PyRun_InteractiveLoop`, otherwise return the result of
+ :cfunc:`PyRun_SimpleFile`. If *filename* is *NULL*, this function uses
+ ``"???"`` as the filename.
+
+
+.. cfunction:: int PyRun_SimpleString(const char *command)
+
+ This is a simplified interface to :cfunc:`PyRun_SimpleStringFlags` below,
+ leaving the *PyCompilerFlags\** argument set to NULL.
+
+
+.. cfunction:: int PyRun_SimpleStringFlags(const char *command, PyCompilerFlags *flags)
+
+ Executes the Python source code from *command* in the :mod:`__main__` module
+ according to the *flags* argument. If :mod:`__main__` does not already exist, it
+ is created. Returns ``0`` on success or ``-1`` if an exception was raised. If
+ there was an error, there is no way to get the exception information. For the
+ meaning of *flags*, see below.
+
+
+.. cfunction:: int PyRun_SimpleFile(FILE *fp, const char *filename)
+
+ This is a simplified interface to :cfunc:`PyRun_SimpleFileExFlags` below,
+ leaving *closeit* set to ``0`` and *flags* set to *NULL*.
+
+
+.. cfunction:: int PyRun_SimpleFileFlags(FILE *fp, const char *filename, PyCompilerFlags *flags)
+
+ This is a simplified interface to :cfunc:`PyRun_SimpleFileExFlags` below,
+ leaving *closeit* set to ``0``.
+
+
+.. cfunction:: int PyRun_SimpleFileEx(FILE *fp, const char *filename, int closeit)
+
+ This is a simplified interface to :cfunc:`PyRun_SimpleFileExFlags` below,
+ leaving *flags* set to *NULL*.
+
+
+.. cfunction:: int PyRun_SimpleFileExFlags(FILE *fp, const char *filename, int closeit, PyCompilerFlags *flags)
+
+ Similar to :cfunc:`PyRun_SimpleStringFlags`, but the Python source code is read
+ from *fp* instead of an in-memory string. *filename* should be the name of the
+ file. If *closeit* is true, the file is closed before PyRun_SimpleFileExFlags
+ returns.
+
+
+.. cfunction:: int PyRun_InteractiveOne(FILE *fp, const char *filename)
+
+ This is a simplified interface to :cfunc:`PyRun_InteractiveOneFlags` below,
+ leaving *flags* set to *NULL*.
+
+
+.. cfunction:: int PyRun_InteractiveOneFlags(FILE *fp, const char *filename, PyCompilerFlags *flags)
+
+ Read and execute a single statement from a file associated with an interactive
+ device according to the *flags* argument. If *filename* is *NULL*, ``"???"`` is
+ used instead. The user will be prompted using ``sys.ps1`` and ``sys.ps2``.
+ Returns ``0`` when the input was executed successfully, ``-1`` if there was an
+ exception, or an error code from the :file:`errcode.h` include file distributed
+ as part of Python if there was a parse error. (Note that :file:`errcode.h` is
+ not included by :file:`Python.h`, so must be included specifically if needed.)
+
+
+.. cfunction:: int PyRun_InteractiveLoop(FILE *fp, const char *filename)
+
+ This is a simplified interface to :cfunc:`PyRun_InteractiveLoopFlags` below,
+ leaving *flags* set to *NULL*.
+
+
+.. cfunction:: int PyRun_InteractiveLoopFlags(FILE *fp, const char *filename, PyCompilerFlags *flags)
+
+ Read and execute statements from a file associated with an interactive device
+ until EOF is reached. If *filename* is *NULL*, ``"???"`` is used instead. The
+ user will be prompted using ``sys.ps1`` and ``sys.ps2``. Returns ``0`` at EOF.
+
+
+.. cfunction:: struct _node* PyParser_SimpleParseString(const char *str, int start)
+
+ This is a simplified interface to
+ :cfunc:`PyParser_SimpleParseStringFlagsFilename` below, leaving *filename* set
+ to *NULL* and *flags* set to ``0``.
+
+
+.. cfunction:: struct _node* PyParser_SimpleParseStringFlags( const char *str, int start, int flags)
+
+ This is a simplified interface to
+ :cfunc:`PyParser_SimpleParseStringFlagsFilename` below, leaving *filename* set
+ to *NULL*.
+
+
+.. cfunction:: struct _node* PyParser_SimpleParseStringFlagsFilename( const char *str, const char *filename, int start, int flags)
+
+ Parse Python source code from *str* using the start token *start* according to
+ the *flags* argument. The result can be used to create a code object which can
+ be evaluated efficiently. This is useful if a code fragment must be evaluated
+ many times.
+
+
+.. cfunction:: struct _node* PyParser_SimpleParseFile(FILE *fp, const char *filename, int start)
+
+ This is a simplified interface to :cfunc:`PyParser_SimpleParseFileFlags` below,
+ leaving *flags* set to ``0``
+
+
+.. cfunction:: struct _node* PyParser_SimpleParseFileFlags(FILE *fp, const char *filename, int start, int flags)
+
+ Similar to :cfunc:`PyParser_SimpleParseStringFlagsFilename`, but the Python
+ source code is read from *fp* instead of an in-memory string.
+
+
+.. cfunction:: PyObject* PyRun_String(const char *str, int start, PyObject *globals, PyObject *locals)
+
+ This is a simplified interface to :cfunc:`PyRun_StringFlags` below, leaving
+ *flags* set to *NULL*.
+
+
+.. cfunction:: PyObject* PyRun_StringFlags(const char *str, int start, PyObject *globals, PyObject *locals, PyCompilerFlags *flags)
+
+ Execute Python source code from *str* in the context specified by the
+ dictionaries *globals* and *locals* with the compiler flags specified by
+ *flags*. The parameter *start* specifies the start token that should be used to
+ parse the source code.
+
+ Returns the result of executing the code as a Python object, or *NULL* if an
+ exception was raised.
+
+
+.. cfunction:: PyObject* PyRun_File(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals)
+
+ This is a simplified interface to :cfunc:`PyRun_FileExFlags` below, leaving
+ *closeit* set to ``0`` and *flags* set to *NULL*.
+
+
+.. cfunction:: PyObject* PyRun_FileEx(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals, int closeit)
+
+ This is a simplified interface to :cfunc:`PyRun_FileExFlags` below, leaving
+ *flags* set to *NULL*.
+
+
+.. cfunction:: PyObject* PyRun_FileFlags(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals, PyCompilerFlags *flags)
+
+ This is a simplified interface to :cfunc:`PyRun_FileExFlags` below, leaving
+ *closeit* set to ``0``.
+
+
+.. cfunction:: PyObject* PyRun_FileExFlags(FILE *fp, const char *filename, int start, PyObject *globals, PyObject *locals, int closeit, PyCompilerFlags *flags)
+
+ Similar to :cfunc:`PyRun_StringFlags`, but the Python source code is read from
+ *fp* instead of an in-memory string. *filename* should be the name of the file.
+ If *closeit* is true, the file is closed before :cfunc:`PyRun_FileExFlags`
+ returns.
+
+
+.. cfunction:: PyObject* Py_CompileString(const char *str, const char *filename, int start)
+
+ This is a simplified interface to :cfunc:`Py_CompileStringFlags` below, leaving
+ *flags* set to *NULL*.
+
+
+.. cfunction:: PyObject* Py_CompileStringFlags(const char *str, const char *filename, int start, PyCompilerFlags *flags)
+
+ Parse and compile the Python source code in *str*, returning the resulting code
+ object. The start token is given by *start*; this can be used to constrain the
+ code which can be compiled and should be :const:`Py_eval_input`,
+ :const:`Py_file_input`, or :const:`Py_single_input`. The filename specified by
+ *filename* is used to construct the code object and may appear in tracebacks or
+ :exc:`SyntaxError` exception messages. This returns *NULL* if the code cannot
+ be parsed or compiled.
+
+
+.. cvar:: int Py_eval_input
+
+ .. index:: single: Py_CompileString()
+
+ The start symbol from the Python grammar for isolated expressions; for use with
+ :cfunc:`Py_CompileString`.
+
+
+.. cvar:: int Py_file_input
+
+ .. index:: single: Py_CompileString()
+
+ The start symbol from the Python grammar for sequences of statements as read
+ from a file or other source; for use with :cfunc:`Py_CompileString`. This is
+ the symbol to use when compiling arbitrarily long Python source code.
+
+
+.. cvar:: int Py_single_input
+
+ .. index:: single: Py_CompileString()
+
+ The start symbol from the Python grammar for a single statement; for use with
+ :cfunc:`Py_CompileString`. This is the symbol used for the interactive
+ interpreter loop.
+
+
+.. ctype:: struct PyCompilerFlags
+
+ This is the structure used to hold compiler flags. In cases where code is only
+ being compiled, it is passed as ``int flags``, and in cases where code is being
+ executed, it is passed as ``PyCompilerFlags *flags``. In this case, ``from
+ __future__ import`` can modify *flags*.
+
+ Whenever ``PyCompilerFlags *flags`` is *NULL*, :attr:`cf_flags` is treated as
+ equal to ``0``, and any modification due to ``from __future__ import`` is
+ discarded. ::
+
+ struct PyCompilerFlags {
+ int cf_flags;
+ }
+
+
+.. cvar:: int CO_FUTURE_DIVISION
+
+ This bit can be set in *flags* to cause division operator ``/`` to be
+ interpreted as "true division" according to :pep:`238`.
+
diff --git a/Doc/conf.py b/Doc/conf.py
new file mode 100644
index 0000000000..6736f533bb
--- /dev/null
+++ b/Doc/conf.py
@@ -0,0 +1,56 @@
+# -*- coding: utf-8 -*-
+#
+# Python documentation build configuration file
+#
+# The contents of this file are pickled, so don't put values in the namespace
+# that aren't pickleable (module imports are okay, they're removed automatically).
+#
+
+# The default replacements for |version| and |release|.
+# If 'auto', Sphinx looks for the Include/patchlevel.h file in the current Python
+# source tree and replaces the values accordingly.
+#
+# The short X.Y version.
+# version = '2.6'
+version = 'auto'
+# The full version, including alpha/beta/rc tags.
+# release = '2.6a0'
+release = 'auto'
+
+# There are two options for replacing |today|: either, you set today to some
+# non-false value, then it is used:
+today = ''
+# Else, today_fmt is used as the format for a strftime call.
+today_fmt = '%B %d, %Y'
+
+# The base URL for download links.
+download_base_url = 'http://docs.python.org/ftp/python/doc/'
+
+# List of files that shouldn't be included in the build.
+unused_files = [
+ 'whatsnew/2.0.rst',
+ 'whatsnew/2.1.rst',
+ 'whatsnew/2.2.rst',
+ 'whatsnew/2.3.rst',
+ 'whatsnew/2.4.rst',
+ 'whatsnew/2.5.rst',
+ 'whatsnew/2.6.rst',
+ 'maclib/scrap.rst',
+ 'library/xmllib.rst',
+ 'library/xml.etree.rst',
+]
+
+# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
+# using the given strftime format.
+last_updated_format = '%b %d, %Y'
+
+# If true, SmartyPants will be used to convert quotes and dashes to
+# typographically correct entities.
+use_smartypants = True
+
+# If true, '()' will be appended to :func: etc. cross-reference text.
+add_function_parentheses = True
+
+# If true, the current module name will be prepended to all description
+# unit titles (such as .. function::).
+add_module_names = True
diff --git a/Doc/contents.rst b/Doc/contents.rst
new file mode 100644
index 0000000000..59a72fa031
--- /dev/null
+++ b/Doc/contents.rst
@@ -0,0 +1,21 @@
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ Python Documentation contents
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+.. toctree::
+
+ whatsnew/3.0.rst
+ tutorial/index.rst
+ reference/index.rst
+ library/index.rst
+ extending/index.rst
+ c-api/index.rst
+ distutils/index.rst
+ install/index.rst
+ documenting/index.rst
+ howto/index.rst
+
+ about.rst
+ bugs.rst
+ copyright.rst
+ license.rst
diff --git a/Doc/copyright.rst b/Doc/copyright.rst
new file mode 100644
index 0000000000..9a472af997
--- /dev/null
+++ b/Doc/copyright.rst
@@ -0,0 +1,19 @@
+*********
+Copyright
+*********
+
+Python and this documentation is:
+
+Copyright © 2001-2007 Python Software Foundation. All rights reserved.
+
+Copyright © 2000 BeOpen.com. All rights reserved.
+
+Copyright © 1995-2000 Corporation for National Research Initiatives. All rights
+reserved.
+
+Copyright © 1991-1995 Stichting Mathematisch Centrum. All rights reserved.
+
+-------
+
+See :ref:`history-and-license` for complete license and permissions information.
+
diff --git a/Doc/data/refcounts.dat b/Doc/data/refcounts.dat
new file mode 100644
index 0000000000..5cb0b7a670
--- /dev/null
+++ b/Doc/data/refcounts.dat
@@ -0,0 +1,1747 @@
+# Created by Skip Montanaro <skip@mojam.com>.
+
+# Format:
+# function ':' type ':' [param name] ':' [refcount effect] ':' [comment]
+# If the param name slot is empty, that line corresponds to the function's
+# return value, otherwise it's the type of the named parameter.
+
+# The first line of a function block gives type/refcount information for the
+# function's return value. Successive lines with the same function name
+# correspond to the function's parameter list and appear in the order the
+# parameters appear in the function's prototype.
+
+# For readability, each function's lines are surrounded by a blank line.
+# The blocks are sorted alphabetically by function name.
+
+# Refcount behavior is given for all PyObject* types: 0 (no change), +1
+# (increment) and -1 (decrement). A blank refcount field indicates the
+# parameter or function value is not a PyObject* and is therefore not
+# subject to reference counting. A special case for the value "null"
+# (without quotes) is used for functions which return a PyObject* type but
+# always return NULL. This is used by some of the PyErr_*() functions, in
+# particular.
+
+# XXX NOTE: the 0/+1/-1 refcount information for arguments is
+# confusing! Much more useful would be to indicate whether the
+# function "steals" a reference to the argument or not. Take for
+# example PyList_SetItem(list, i, item). This lists as a 0 change for
+# both the list and the item arguments. However, in fact it steals a
+# reference to the item argument!
+
+# The parameter names are as they appear in the API manual, not the source
+# code.
+
+PyBool_FromLong:PyObject*::+1:
+PyBool_FromLong:long:v:0:
+
+PyBuffer_FromObject:PyObject*::+1:
+PyBuffer_FromObject:PyObject*:base:+1:
+PyBuffer_FromObject:int:offset::
+PyBuffer_FromObject:int:size::
+
+PyBuffer_FromReadWriteObject:PyObject*::+1:
+PyBuffer_FromReadWriteObject:PyObject*:base:+1:
+PyBuffer_FromReadWriteObject:int:offset::
+PyBuffer_FromReadWriteObject:int:size::
+
+PyBuffer_FromMemory:PyObject*::+1:
+PyBuffer_FromMemory:void*:ptr::
+PyBuffer_FromMemory:int:size::
+
+PyBuffer_FromReadWriteMemory:PyObject*::+1:
+PyBuffer_FromReadWriteMemory:void*:ptr::
+PyBuffer_FromReadWriteMemory:int:size::
+
+PyBuffer_New:PyObject*::+1:
+PyBuffer_New:int:size::
+
+PyCObject_AsVoidPtr:void*:::
+PyCObject_AsVoidPtr:PyObject*:self:0:
+
+PyCObject_FromVoidPtr:PyObject*::+1:
+PyCObject_FromVoidPtr:void*:cobj::
+PyCObject_FromVoidPtr::void (* destr)(void* )::
+
+PyCObject_FromVoidPtrAndDesc:PyObject*::+1:
+PyCObject_FromVoidPtrAndDesc:void*:cobj::
+PyCObject_FromVoidPtrAndDesc:void*:desc::
+PyCObject_FromVoidPtrAndDesc:void(*)(void*,void*):destr::
+
+PyCObject_GetDesc:void*:::
+PyCObject_GetDesc:PyObject*:self:0:
+
+PyCell_New:PyObject*::+1:
+PyCell_New:PyObject*:ob:0:
+
+PyCell_GET:PyObject*::0:
+PyCell_GET:PyObject*:ob:0:
+
+PyCell_Get:PyObject*::+1:
+PyCell_Get:PyObject*:cell:0:
+
+PyCell_SET:void:::
+PyCell_SET:PyObject*:cell:0:
+PyCell_SET:PyObject*:value:0:
+
+PyCell_Set:int:::
+PyCell_Set:PyObject*:cell:0:
+PyCell_Set:PyObject*:value:0:
+
+PyCallIter_New:PyObject*::+1:
+PyCallIter_New:PyObject*:callable::
+PyCallIter_New:PyObject*:sentinel::
+
+PyCallable_Check:int:::
+PyCallable_Check:PyObject*:o:0:
+
+PyComplex_AsCComplex:Py_complex:::
+PyComplex_AsCComplex:PyObject*:op:0:
+
+PyComplex_Check:int:::
+PyComplex_Check:PyObject*:p:0:
+
+PyComplex_FromCComplex:PyObject*::+1:
+PyComplex_FromCComplex::Py_complex v::
+
+PyComplex_FromDoubles:PyObject*::+1:
+PyComplex_FromDoubles::double real::
+PyComplex_FromDoubles::double imag::
+
+PyComplex_ImagAsDouble:double:::
+PyComplex_ImagAsDouble:PyObject*:op:0:
+
+PyComplex_RealAsDouble:double:::
+PyComplex_RealAsDouble:PyObject*:op:0:
+
+PyDate_FromDate:PyObject*::+1:
+PyDate_FromDate:int:year::
+PyDate_FromDate:int:month::
+PyDate_FromDate:int:day::
+
+PyDate_FromTimestamp:PyObject*::+1:
+PyDate_FromTimestamp:PyObject*:args:0:
+
+PyDateTime_FromDateAndTime:PyObject*::+1:
+PyDateTime_FromDateAndTime:int:year::
+PyDateTime_FromDateAndTime:int:month::
+PyDateTime_FromDateAndTime:int:day::
+PyDateTime_FromDateAndTime:int:hour::
+PyDateTime_FromDateAndTime:int:minute::
+PyDateTime_FromDateAndTime:int:second::
+PyDateTime_FromDateAndTime:int:usecond::
+
+PyDateTime_FromTimestamp:PyObject*::+1:
+PyDateTime_FromTimestamp:PyObject*:args:0:
+
+PyDelta_FromDSU:PyObject*::+1:
+PyDelta_FromDSU:int:days::
+PyDelta_FromDSU:int:seconds::
+PyDelta_FromDSU:int:useconds::
+
+PyDescr_NewClassMethod:PyObject*::+1:
+PyDescr_NewClassMethod:PyTypeObject*:type::
+PyDescr_NewClassMethod:PyMethodDef*:method::
+
+PyDescr_NewGetSet:PyObject*::+1:
+PyDescr_NewGetSet:PyTypeObject*:type::
+PyDescr_NewGetSet:PyGetSetDef*:getset::
+
+PyDescr_NewMember:PyObject*::+1:
+PyDescr_NewMember:PyTypeObject*:type::
+PyDescr_NewMember:PyMemberDef*:member::
+
+PyDescr_NewMethod:PyObject*::+1:
+PyDescr_NewMethod:PyTypeObject*:type::
+PyDescr_NewMethod:PyMethodDef*:meth::
+
+PyDescr_NewWrapper:PyObject*::+1:
+PyDescr_NewWrapper:PyTypeObject*:type::
+PyDescr_NewWrapper:struct wrapperbase*:base::
+PyDescr_NewWrapper:void*:wrapped::
+
+PyDict_Check:int:::
+PyDict_Check:PyObject*:p:0:
+
+PyDict_Clear:void:::
+PyDict_Clear:PyObject*:p:0:
+
+PyDict_DelItem:int:::
+PyDict_DelItem:PyObject*:p:0:
+PyDict_DelItem:PyObject*:key:0:
+
+PyDict_DelItemString:int:::
+PyDict_DelItemString:PyObject*:p:0:
+PyDict_DelItemString:char*:key::
+
+PyDict_GetItem:PyObject*::0:0
+PyDict_GetItem:PyObject*:p:0:
+PyDict_GetItem:PyObject*:key:0:
+
+PyDict_GetItemString:PyObject*::0:
+PyDict_GetItemString:PyObject*:p:0:
+PyDict_GetItemString:char*:key::
+
+PyDict_Items:PyObject*::+1:
+PyDict_Items:PyObject*:p:0:
+
+PyDict_Keys:PyObject*::+1:
+PyDict_Keys:PyObject*:p:0:
+
+PyDict_New:PyObject*::+1:
+
+PyDict_Copy:PyObject*::+1:
+PyDict_Copy:PyObject*:p:0:
+
+PyDict_Next:int:::
+PyDict_Next:PyObject*:p:0:
+PyDict_Next:int:ppos::
+PyDict_Next:PyObject**:pkey:0:
+PyDict_Next:PyObject**:pvalue:0:
+
+PyDict_SetItem:int:::
+PyDict_SetItem:PyObject*:p:0:
+PyDict_SetItem:PyObject*:key:+1:
+PyDict_SetItem:PyObject*:val:+1:
+
+PyDict_SetItemString:int:::
+PyDict_SetItemString:PyObject*:p:0:
+PyDict_SetItemString:char*:key::
+PyDict_SetItemString:PyObject*:val:+1:
+
+PyDict_Size:int:::
+PyDict_Size:PyObject*:p::
+
+PyDict_Values:PyObject*::+1:
+PyDict_Values:PyObject*:p:0:
+
+PyDictProxy_New:PyObject*::+1:
+PyDictProxy_New:PyObject*:dict:0:
+
+PyErr_BadArgument:int:::
+
+PyErr_BadInternalCall:void:::
+
+PyErr_CheckSignals:int:::
+
+PyErr_Clear:void:::
+
+PyErr_ExceptionMatches:int:::
+PyErr_ExceptionMatches:PyObject*:exc:0:
+
+PyErr_Fetch:void:::
+PyErr_Fetch:PyObject**:ptype:0:
+PyErr_Fetch:PyObject**:pvalue:0:
+PyErr_Fetch:PyObject**:ptraceback:0:
+
+PyErr_GivenExceptionMatches:int:::
+PyErr_GivenExceptionMatches:PyObject*:given:0:
+PyErr_GivenExceptionMatches:PyObject*:exc:0:
+
+PyErr_NewException:PyObject*::+1:
+PyErr_NewException:char*:name::
+PyErr_NewException:PyObject*:base:0:
+PyErr_NewException:PyObject*:dict:0:
+
+PyErr_NoMemory:PyObject*::null:
+
+PyErr_NormalizeException:void:::
+PyErr_NormalizeException:PyObject**:exc::???
+PyErr_NormalizeException:PyObject**:val::???
+PyErr_NormalizeException:PyObject**:tb::???
+
+PyErr_Occurred:PyObject*::0:
+
+PyErr_Print:void:::
+
+PyErr_Restore:void:::
+PyErr_Restore:PyObject*:type:-1:
+PyErr_Restore:PyObject*:value:-1:
+PyErr_Restore:PyObject*:traceback:-1:
+
+PyErr_SetExcFromWindowsErr:PyObject*::null:
+PyErr_SetExcFromWindowsErr:PyObject*:type:0:
+PyErr_SetExcFromWindowsErr:int:ierr::
+
+PyErr_SetExcFromWindowsErrWithFilename:PyObject*::null:
+PyErr_SetExcFromWindowsErrWithFilename:PyObject*:type:0:
+PyErr_SetExcFromWindowsErrWithFilename:int:ierr::
+PyErr_SetExcFromWindowsErrWithFilename:char*:filename::
+
+PyErr_SetFromErrno:PyObject*::null:
+PyErr_SetFromErrno:PyObject*:type:0:
+
+PyErr_SetFromErrnoWithFilename:PyObject*::null:
+PyErr_SetFromErrnoWithFilename:PyObject*:type:0:
+PyErr_SetFromErrnoWithFilename:char*:filename::
+
+PyErr_SetFromWindowsErr:PyObject*::null:
+PyErr_SetFromWindowsErr:int:ierr::
+
+PyErr_SetFromWindowsErrWithFilename:PyObject*::null:
+PyErr_SetFromWindowsErrWithFilename:int:ierr::
+PyErr_SetFromWindowsErrWithFilename:char*:filename::
+
+PyErr_SetInterrupt:void:::
+
+PyErr_SetNone:void:::
+PyErr_SetNone:PyObject*:type:+1:
+
+PyErr_SetObject:void:::
+PyErr_SetObject:PyObject*:type:+1:
+PyErr_SetObject:PyObject*:value:+1:
+
+PyErr_SetString:void:::
+PyErr_SetString:PyObject*:type:+1:
+PyErr_SetString:char*:message::
+
+PyErr_Format:PyObject*::null:
+PyErr_Format:PyObject*:exception:+1:
+PyErr_Format:char*:format::
+PyErr_Format::...::
+
+PyErr_WarnEx:int:::
+PyErr_WarnEx:PyObject*:category:0:
+PyErr_WarnEx:const char*:message::
+PyErr_WarnEx:Py_ssize_t:stack_level::
+
+PyEval_AcquireLock:void:::
+
+PyEval_AcquireThread:void:::
+PyEval_AcquireThread:PyThreadState*:tstate::
+
+PyEval_InitThreads:void:::
+
+PyEval_ReleaseLock:void:::
+
+PyEval_ReleaseThread:void:::
+PyEval_ReleaseThread:PyThreadState*:tstate::
+
+PyEval_RestoreThread:void:::
+PyEval_RestoreThread:PyThreadState*:tstate::
+
+PyEval_SaveThread:PyThreadState*:::
+
+PyEval_EvalCode:PyObject*::+1:
+PyEval_EvalCode:PyCodeObject*:co:0:
+PyEval_EvalCode:PyObject*:globals:0:
+PyEval_EvalCode:PyObject*:locals:0:
+
+PyFile_AsFile:FILE*:::
+PyFile_AsFile:PyFileObject*:p:0:
+
+PyFile_Check:int:::
+PyFile_Check:PyObject*:p:0:
+
+PyFile_FromFile:PyObject*::+1:
+PyFile_FromFile:FILE*:fp::
+PyFile_FromFile:char*:name::
+PyFile_FromFile:char*:mode::
+PyFile_FromFile:int(*:close)::
+
+PyFile_FromString:PyObject*::+1:
+PyFile_FromString:char*:name::
+PyFile_FromString:char*:mode::
+
+PyFile_GetLine:PyObject*::+1:
+PyFile_GetLine:PyObject*:p::
+PyFile_GetLine:int:n::
+
+PyFile_Name:PyObject*::0:
+PyFile_Name:PyObject*:p:0:
+
+PyFile_SetBufSize:void:::
+PyFile_SetBufSize:PyFileObject*:p:0:
+PyFile_SetBufSize:int:n::
+
+PyFile_SoftSpace:int:::
+PyFile_SoftSpace:PyFileObject*:p:0:
+PyFile_SoftSpace:int:newflag::
+
+PyFile_WriteObject:int:::
+PyFile_WriteObject:PyObject*:obj:0:
+PyFile_WriteObject:PyFileObject*:p:0:
+PyFile_WriteObject:int:flags::
+
+PyFile_WriteString:int:::
+PyFile_WriteString:const char*:s::
+PyFile_WriteString:PyFileObject*:p:0:
+PyFile_WriteString:int:flags::
+
+PyFloat_AS_DOUBLE:double:::
+PyFloat_AS_DOUBLE:PyObject*:pyfloat:0:
+
+PyFloat_AsDouble:double:::
+PyFloat_AsDouble:PyObject*:pyfloat:0:
+
+PyFloat_Check:int:::
+PyFloat_Check:PyObject*:p:0:
+
+PyFloat_FromDouble:PyObject*::+1:
+PyFloat_FromDouble:double:v::
+
+PyFloat_FromString:PyObject*::+1:
+PyFloat_FromString:PyObject*:str:0:
+
+PyFrozenSet_New:PyObject*::+1:
+PyFrozenSet_New:PyObject*:iterable:0:
+
+PyFunction_GetClosure:PyObject*::0:
+PyFunction_GetClosure:PyObject*:op:0:
+
+PyFunction_GetCode:PyObject*::0:
+PyFunction_GetCode:PyObject*:op:0:
+
+PyFunction_GetDefaults:PyObject*::0:
+PyFunction_GetDefaults:PyObject*:op:0:
+
+PyFunction_GetGlobals:PyObject*::0:
+PyFunction_GetGlobals:PyObject*:op:0:
+
+PyFunction_GetModule:PyObject*::0:
+PyFunction_GetModule:PyObject*:op:0:
+
+PyFunction_New:PyObject*::+1:
+PyFunction_New:PyObject*:code:+1:
+PyFunction_New:PyObject*:globals:+1:
+
+PyFunction_SetClosure:int:::
+PyFunction_SetClosure:PyObject*:op:0:
+PyFunction_SetClosure:PyObject*:closure:+1:
+
+PyFunction_SetDefaults:int:::
+PyFunction_SetDefaults:PyObject*:op:0:
+PyFunction_SetDefaults:PyObject*:defaults:+1:
+
+PyGen_New:PyObject*::+1:
+PyGen_New:PyFrameObject*:frame:0:
+
+Py_InitModule:PyObject*::0:
+Py_InitModule:char*:name::
+Py_InitModule:PyMethodDef[]:methods::
+
+Py_InitModule3:PyObject*::0:
+Py_InitModule3:char*:name::
+Py_InitModule3:PyMethodDef[]:methods::
+Py_InitModule3:char*:doc::
+
+Py_InitModule4:PyObject*::0:
+Py_InitModule4:char*:name::
+Py_InitModule4:PyMethodDef[]:methods::
+Py_InitModule4:char*:doc::
+Py_InitModule4:PyObject*:self::
+Py_InitModule4:int:apiver::usually provided by Py_InitModule or Py_InitModule3
+
+PyImport_AddModule:PyObject*::0:reference borrowed from sys.modules
+PyImport_AddModule:char*:name::
+
+PyImport_Cleanup:void:::
+
+PyImport_ExecCodeModule:PyObject*::+1:
+PyImport_ExecCodeModule:char*:name::
+PyImport_ExecCodeModule:PyObject*:co:0:
+
+PyImport_GetMagicNumber:long:::
+
+PyImport_GetModuleDict:PyObject*::0:
+
+PyImport_Import:PyObject*::+1:
+PyImport_Import:PyObject*:name:0:
+
+PyImport_ImportFrozenModule:int:::
+PyImport_ImportFrozenModule:char*:::
+
+PyImport_ImportModule:PyObject*::+1:
+PyImport_ImportModule:char*:name::
+
+PyImport_ImportModuleEx:PyObject*::+1:
+PyImport_ImportModuleEx:char*:name::
+PyImport_ImportModuleEx:PyObject*:globals:0:???
+PyImport_ImportModuleEx:PyObject*:locals:0:???
+PyImport_ImportModuleEx:PyObject*:fromlist:0:???
+
+PyImport_ReloadModule:PyObject*::+1:
+PyImport_ReloadModule:PyObject*:m:0:
+
+PyInstance_New:PyObject*::+1:
+PyInstance_New:PyObject*:klass:+1:
+PyInstance_New:PyObject*:arg:0:
+PyInstance_New:PyObject*:kw:0:
+
+PyInstance_NewRaw:PyObject*::+1:
+PyInstance_NewRaw:PyObject*:klass:+1:
+PyInstance_NewRaw:PyObject*:dict:+1:
+
+PyInt_AS_LONG:long:::
+PyInt_AS_LONG:PyIntObject*:io:0:
+
+PyInt_AsLong:long:::
+PyInt_AsLong:PyObject*:io:0:
+
+PyInt_Check:int:::
+PyInt_Check:PyObject*:op:0:
+
+PyInt_FromLong:PyObject*::+1:
+PyInt_FromLong:long:ival::
+
+PyInt_FromString:PyObject*::+1:
+PyInt_FromString:char*:str:0:
+PyInt_FromString:char**:pend:0:
+PyInt_FromString:int:base:0:
+
+PyInt_FromSsize_t:PyObject*::+1:
+PyInt_FromSsize_t:Py_ssize_t:ival::
+
+PyInt_GetMax:long:::
+
+PyInterpreterState_Clear:void:::
+PyInterpreterState_Clear:PyInterpreterState*:interp::
+
+PyInterpreterState_Delete:void:::
+PyInterpreterState_Delete:PyInterpreterState*:interp::
+
+PyInterpreterState_New:PyInterpreterState*:::
+
+PyIter_Check:int:o:0:
+
+PyIter_Next:PyObject*::+1:
+PyIter_Next:PyObject*:o:0:
+
+PyList_Append:int:::
+PyList_Append:PyObject*:list:0:
+PyList_Append:PyObject*:item:+1:
+
+PyList_AsTuple:PyObject*::+1:
+PyList_AsTuple:PyObject*:list:0:
+
+PyList_Check:int:::
+PyList_Check:PyObject*:p:0:
+
+PyList_GET_ITEM:PyObject*::0:
+PyList_GET_ITEM:PyObject*:list:0:
+PyList_GET_ITEM:int:i:0:
+
+PyList_GET_SIZE:int:::
+PyList_GET_SIZE:PyObject*:list:0:
+
+PyList_GetItem:PyObject*::0:
+PyList_GetItem:PyObject*:list:0:
+PyList_GetItem:int:index::
+
+PyList_GetSlice:PyObject*::+1:
+PyList_GetSlice:PyObject*:list:0:
+PyList_GetSlice:int:low::
+PyList_GetSlice:int:high::
+
+PyList_Insert:int:::
+PyList_Insert:PyObject*:list:0:
+PyList_Insert:int:index::
+PyList_Insert:PyObject*:item:+1:
+
+PyList_New:PyObject*::+1:
+PyList_New:int:len::
+
+PyList_Reverse:int:::
+PyList_Reverse:PyObject*:list:0:
+
+PyList_SET_ITEM:void:::
+PyList_SET_ITEM:PyObject*:list:0:
+PyList_SET_ITEM:int:i::
+PyList_SET_ITEM:PyObject*:o:0:
+
+PyList_SetItem:int:::
+PyList_SetItem:PyObject*:list:0:
+PyList_SetItem:int:index::
+PyList_SetItem:PyObject*:item:0:
+
+PyList_SetSlice:int:::
+PyList_SetSlice:PyObject*:list:0:
+PyList_SetSlice:int:low::
+PyList_SetSlice:int:high::
+PyList_SetSlice:PyObject*:itemlist:0:but increfs its elements?
+
+PyList_Size:int:::
+PyList_Size:PyObject*:list:0:
+
+PyList_Sort:int:::
+PyList_Sort:PyObject*:list:0:
+
+PyLong_AsDouble:double:::
+PyLong_AsDouble:PyObject*:pylong:0:
+
+PyLong_AsLong:long:::
+PyLong_AsLong:PyObject*:pylong:0:
+
+PyLong_AsUnsignedLong:unsigned long:::
+PyLong_AsUnsignedLong:PyObject*:pylong:0:
+
+PyLong_Check:int:::
+PyLong_Check:PyObject*:p:0:
+
+PyLong_FromDouble:PyObject*::+1:
+PyLong_FromDouble:double:v::
+
+PyLong_FromLong:PyObject*::+1:
+PyLong_FromLong:long:v::
+
+PyLong_FromLongLong:PyObject*::+1:
+PyLong_FromLongLong:long long:v::
+
+PyLong_FromUnsignedLongLong:PyObject*::+1:
+PyLong_FromUnsignedLongLong:unsigned long long:v::
+
+PyLong_FromString:PyObject*::+1:
+PyLong_FromString:char*:str::
+PyLong_FromString:char**:pend::
+PyLong_FromString:int:base::
+
+PyLong_FromUnicode:PyObject*::+1:
+PyLong_FromUnicode:Py_UNICODE:u::
+PyLong_FromUnicode:int:length::
+PyLong_FromUnicode:int:base::
+
+PyLong_FromUnsignedLong:PyObject*::+1:
+PyLong_FromUnsignedLong:unsignedlong:v::
+
+PyLong_FromVoidPtr:PyObject*::+1:
+PyLong_FromVoidPtr:void*:p::
+
+PyMapping_Check:int:::
+PyMapping_Check:PyObject*:o:0:
+
+PyMapping_DelItem:int:::
+PyMapping_DelItem:PyObject*:o:0:
+PyMapping_DelItem:PyObject*:key:0:
+
+PyMapping_DelItemString:int:::
+PyMapping_DelItemString:PyObject*:o:0:
+PyMapping_DelItemString:char*:key::
+
+PyMapping_GetItemString:PyObject*::+1:
+PyMapping_GetItemString:PyObject*:o:0:
+PyMapping_GetItemString:char*:key::
+
+PyMapping_HasKey:int:::
+PyMapping_HasKey:PyObject*:o:0:
+PyMapping_HasKey:PyObject*:key::
+
+PyMapping_HasKeyString:int:::
+PyMapping_HasKeyString:PyObject*:o:0:
+PyMapping_HasKeyString:char*:key::
+
+PyMapping_Items:PyObject*::+1:
+PyMapping_Items:PyObject*:o:0:
+
+PyMapping_Keys:PyObject*::+1:
+PyMapping_Keys:PyObject*:o:0:
+
+PyMapping_Length:int:::
+PyMapping_Length:PyObject*:o:0:
+
+PyMapping_SetItemString:int:::
+PyMapping_SetItemString:PyObject*:o:0:
+PyMapping_SetItemString:char*:key::
+PyMapping_SetItemString:PyObject*:v:+1:
+
+PyMapping_Values:PyObject*::+1:
+PyMapping_Values:PyObject*:o:0:
+
+PyMarshal_ReadLastObjectFromFile:PyObject*::+1:
+PyMarshal_ReadLastObjectFromFile:FILE*:file::
+
+PyMarshal_ReadObjectFromFile:PyObject*::+1:
+PyMarshal_ReadObjectFromFile:FILE*:file::
+
+PyMarshal_ReadObjectFromString:PyObject*::+1:
+PyMarshal_ReadObjectFromString:char*:string::
+PyMarshal_ReadObjectFromString:int:len::
+
+PyMarshal_WriteObjectToString:PyObject*::+1:
+PyMarshal_WriteObjectToString:PyObject*:value:0:
+
+PyMethod_Class:PyObject*::0:
+PyMethod_Class:PyObject*:im:0:
+
+PyMethod_Function:PyObject*::0:
+PyMethod_Function:PyObject*:im:0:
+
+PyMethod_GET_CLASS:PyObject*::0:
+PyMethod_GET_CLASS:PyObject*:im:0:
+
+PyMethod_GET_FUNCTION:PyObject*::0:
+PyMethod_GET_FUNCTION:PyObject*:im:0:
+
+PyMethod_GET_SELF:PyObject*::0:
+PyMethod_GET_SELF:PyObject*:im:0:
+
+PyMethod_New:PyObject*::+1:
+PyMethod_New:PyObject*:func:0:
+PyMethod_New:PyObject*:self:0:
+PyMethod_New:PyObject*:class:0:
+
+PyMethod_Self:PyObject*::0:
+PyMethod_Self:PyObject*:im:0:
+
+PyModule_GetDict:PyObject*::0:
+PyModule_GetDict::PyObject* module:0:
+
+PyModule_GetFilename:char*:::
+PyModule_GetFilename:PyObject*:module:0:
+
+PyModule_GetName:char*:::
+PyModule_GetName:PyObject*:module:0:
+
+PyModule_New:PyObject*::+1:
+PyModule_New::char* name::
+
+PyNumber_Absolute:PyObject*::+1:
+PyNumber_Absolute:PyObject*:o:0:
+
+PyNumber_Add:PyObject*::+1:
+PyNumber_Add:PyObject*:o1:0:
+PyNumber_Add:PyObject*:o2:0:
+
+PyNumber_And:PyObject*::+1:
+PyNumber_And:PyObject*:o1:0:
+PyNumber_And:PyObject*:o2:0:
+
+PyNumber_Check:PyObject*:o:0:
+PyNumber_Check:int:::
+
+PyNumber_Divide:PyObject*::+1:
+PyNumber_Divide:PyObject*:o1:0:
+PyNumber_Divide:PyObject*:o2:0:
+
+PyNumber_Divmod:PyObject*::+1:
+PyNumber_Divmod:PyObject*:o1:0:
+PyNumber_Divmod:PyObject*:o2:0:
+
+PyNumber_Float:PyObject*::+1:
+PyNumber_Float:PyObject*:o:0:
+
+PyNumber_FloorDivide:PyObject*::+1:
+PyNumber_FloorDivide:PyObject*:v:0:
+PyNumber_FloorDivide:PyObject*:w:0:
+
+PyNumber_InPlaceAdd:PyObject*::+1:
+PyNumber_InPlaceAdd:PyObject*:v:0:
+PyNumber_InPlaceAdd:PyObject*:w:0:
+
+PyNumber_InPlaceAnd:PyObject*::+1:
+PyNumber_InPlaceAnd:PyObject*:v:0:
+PyNumber_InPlaceAnd:PyObject*:w:0:
+
+PyNumber_InPlaceDivide:PyObject*::+1:
+PyNumber_InPlaceDivide:PyObject*:v:0:
+PyNumber_InPlaceDivide:PyObject*:w:0:
+
+PyNumber_InPlaceFloorDivide:PyObject*::+1:
+PyNumber_InPlaceFloorDivide:PyObject*:v:0:
+PyNumber_InPlaceFloorDivide:PyObject*:w:0:
+
+PyNumber_InPlaceLshift:PyObject*::+1:
+PyNumber_InPlaceLshift:PyObject*:v:0:
+PyNumber_InPlaceLshift:PyObject*:w:0:
+
+PyNumber_InPlaceMultiply:PyObject*::+1:
+PyNumber_InPlaceMultiply:PyObject*:v:0:
+PyNumber_InPlaceMultiply:PyObject*:w:0:
+
+PyNumber_InPlaceOr:PyObject*::+1:
+PyNumber_InPlaceOr:PyObject*:v:0:
+PyNumber_InPlaceOr:PyObject*:w:0:
+
+PyNumber_InPlacePower:PyObject*::+1:
+PyNumber_InPlacePower:PyObject*:v:0:
+PyNumber_InPlacePower:PyObject*:w:0:
+PyNumber_InPlacePower:PyObject*:z:0:
+
+PyNumber_InPlaceRemainder:PyObject*::+1:
+PyNumber_InPlaceRemainder:PyObject*:v:0:
+PyNumber_InPlaceRemainder:PyObject*:w:0:
+
+PyNumber_InPlaceRshift:PyObject*::+1:
+PyNumber_InPlaceRshift:PyObject*:v:0:
+PyNumber_InPlaceRshift:PyObject*:w:0:
+
+PyNumber_InPlaceSubtract:PyObject*::+1:
+PyNumber_InPlaceSubtract:PyObject*:v:0:
+PyNumber_InPlaceSubtract:PyObject*:w:0:
+
+PyNumber_InPlaceTrueDivide:PyObject*::+1:
+PyNumber_InPlaceTrueDivide:PyObject*:v:0:
+PyNumber_InPlaceTrueDivide:PyObject*:w:0:
+
+PyNumber_InPlaceXor:PyObject*::+1:
+PyNumber_InPlaceXor:PyObject*:v:0:
+PyNumber_InPlaceXor:PyObject*:w:0:
+
+PyNumber_Int:PyObject*::+1:
+PyNumber_Int:PyObject*:o:0:
+
+PyNumber_Invert:PyObject*::+1:
+PyNumber_Invert:PyObject*:o:0:
+
+PyNumber_Long:PyObject*::+1:
+PyNumber_Long:PyObject*:o:0:
+
+PyNumber_Lshift:PyObject*::+1:
+PyNumber_Lshift:PyObject*:o1:0:
+PyNumber_Lshift:PyObject*:o2:0:
+
+PyNumber_Multiply:PyObject*::+1:
+PyNumber_Multiply:PyObject*:o1:0:
+PyNumber_Multiply:PyObject*:o2:0:
+
+PyNumber_Negative:PyObject*::+1:
+PyNumber_Negative:PyObject*:o:0:
+
+PyNumber_Or:PyObject*::+1:
+PyNumber_Or:PyObject*:o1:0:
+PyNumber_Or:PyObject*:o2:0:
+
+PyNumber_Positive:PyObject*::+1:
+PyNumber_Positive:PyObject*:o:0:
+
+PyNumber_Power:PyObject*::+1:
+PyNumber_Power:PyObject*:o1:0:
+PyNumber_Power:PyObject*:o2:0:
+PyNumber_Power:PyObject*:o3:0:
+
+PyNumber_Remainder:PyObject*::+1:
+PyNumber_Remainder:PyObject*:o1:0:
+PyNumber_Remainder:PyObject*:o2:0:
+
+PyNumber_Rshift:PyObject*::+1:
+PyNumber_Rshift:PyObject*:o1:0:
+PyNumber_Rshift:PyObject*:o2:0:
+
+PyNumber_Subtract:PyObject*::+1:
+PyNumber_Subtract:PyObject*:o1:0:
+PyNumber_Subtract:PyObject*:o2:0:
+
+PyNumber_TrueDivide:PyObject*::+1:
+PyNumber_TrueDivide:PyObject*:v:0:
+PyNumber_TrueDivide:PyObject*:w:0:
+
+PyNumber_Xor:PyObject*::+1:
+PyNumber_Xor:PyObject*:o1:0:
+PyNumber_Xor:PyObject*:o2:0:
+
+PyOS_GetLastModificationTime:long:::
+PyOS_GetLastModificationTime:char*:filename::
+
+PyObject_AsFileDescriptor:int:::
+PyObject_AsFileDescriptor:PyObject*:o:0:
+
+PyObject_Call:PyObject*::+1:
+PyObject_Call:PyObject*:callable_object:0:
+PyObject_Call:PyObject*:args:0:
+PyObject_Call:PyObject*:kw:0:
+
+PyObject_CallFunction:PyObject*::+1:
+PyObject_CallFunction:PyObject*:callable_object:0:
+PyObject_CallFunction:char*:format::
+PyObject_CallFunction::...::
+
+PyObject_CallFunctionObjArgs:PyObject*::+1:
+PyObject_CallFunctionObjArgs:PyObject*:callable:0:
+PyObject_CallFunctionObjArgs::...::
+
+PyObject_CallMethod:PyObject*::+1:
+PyObject_CallMethod:PyObject*:o:0:
+PyObject_CallMethod:char*:m::
+PyObject_CallMethod:char*:format::
+PyObject_CallMethod::...::
+
+PyObject_CallMethodObjArgs:PyObject*::+1:
+PyObject_CallMethodObjArgs:PyObject*:o:0:
+PyObject_CallMethodObjArgs:char*:name::
+PyObject_CallMethodObjArgs::...::
+
+PyObject_CallObject:PyObject*::+1:
+PyObject_CallObject:PyObject*:callable_object:0:
+PyObject_CallObject:PyObject*:args:0:
+
+PyObject_Cmp:int:::
+PyObject_Cmp:PyObject*:o1:0:
+PyObject_Cmp:PyObject*:o2:0:
+PyObject_Cmp:int*:result::
+
+PyObject_Compare:int:::
+PyObject_Compare:PyObject*:o1:0:
+PyObject_Compare:PyObject*:o2:0:
+
+PyObject_DelAttr:int:::
+PyObject_DelAttr:PyObject*:o:0:
+PyObject_DelAttr:PyObject*:attr_name:0:
+
+PyObject_DelAttrString:int:::
+PyObject_DelAttrString:PyObject*:o:0:
+PyObject_DelAttrString:char*:attr_name::
+
+PyObject_DelItem:int:::
+PyObject_DelItem:PyObject*:o:0:
+PyObject_DelItem:PyObject*:key:0:
+
+PyObject_Dir:PyObject*::+1:
+PyObject_Dir:PyObject*:o:0:
+
+PyObject_GetAttr:PyObject*::+1:
+PyObject_GetAttr:PyObject*:o:0:
+PyObject_GetAttr:PyObject*:attr_name:0:
+
+PyObject_GetAttrString:PyObject*::+1:
+PyObject_GetAttrString:PyObject*:o:0:
+PyObject_GetAttrString:char*:attr_name::
+
+PyObject_GetItem:PyObject*::+1:
+PyObject_GetItem:PyObject*:o:0:
+PyObject_GetItem:PyObject*:key:0:
+
+PyObject_GetIter:PyObject*::+1:
+PyObject_GetIter:PyObject*:o:0:
+
+PyObject_HasAttr:int:::
+PyObject_HasAttr:PyObject*:o:0:
+PyObject_HasAttr:PyObject*:attr_name:0:
+
+PyObject_HasAttrString:int:::
+PyObject_HasAttrString:PyObject*:o:0:
+PyObject_HasAttrString:char*:attr_name:0:
+
+PyObject_Hash:int:::
+PyObject_Hash:PyObject*:o:0:
+
+PyObject_IsTrue:int:::
+PyObject_IsTrue:PyObject*:o:0:
+
+PyObject_Init:PyObject*::0:
+PyObject_Init:PyObject*:op:0:
+
+PyObject_InitVar:PyVarObject*::0:
+PyObject_InitVar:PyVarObject*:op:0:
+
+PyObject_Length:int:::
+PyObject_Length:PyObject*:o:0:
+
+PyObject_NEW:PyObject*::+1:
+
+PyObject_New:PyObject*::+1:
+
+PyObject_NEW_VAR:PyObject*::+1:
+
+PyObject_NewVar:PyObject*::+1:
+
+PyObject_Print:int:::
+PyObject_Print:PyObject*:o:0:
+PyObject_Print:FILE*:fp::
+PyObject_Print:int:flags::
+
+PyObject_Repr:PyObject*::+1:
+PyObject_Repr:PyObject*:o:0:
+
+PyObject_RichCompare:PyObject*::+1:
+PyObject_RichCompare:PyObject*:o1:0:
+PyObject_RichCompare:PyObject*:o2:0:
+PyObject_RichCompare:int:opid::
+
+PyObject_RichCompareBool:int:::
+PyObject_RichCompareBool:PyObject*:o1:0:
+PyObject_RichCompareBool:PyObject*:o2:0:
+PyObject_RichCompareBool:int:opid::
+
+PyObject_SetAttr:int:::
+PyObject_SetAttr:PyObject*:o:0:
+PyObject_SetAttr:PyObject*:attr_name:0:
+PyObject_SetAttr:PyObject*:v:+1:
+
+PyObject_SetAttrString:int:::
+PyObject_SetAttrString:PyObject*:o:0:
+PyObject_SetAttrString:char*:attr_name::
+PyObject_SetAttrString:PyObject*:v:+1:
+
+PyObject_SetItem:int:::
+PyObject_SetItem:PyObject*:o:0:
+PyObject_SetItem:PyObject*:key:0:
+PyObject_SetItem:PyObject*:v:+1:
+
+PyObject_Str:PyObject*::+1:
+PyObject_Str:PyObject*:o:0:
+
+PyObject_Type:PyObject*::+1:
+PyObject_Type:PyObject*:o:0:
+
+PyObject_Unicode:PyObject*::+1:
+PyObject_Unicode:PyObject*:o:0:
+
+PyParser_SimpleParseFile:struct _node*:::
+PyParser_SimpleParseFile:FILE*:fp::
+PyParser_SimpleParseFile:char*:filename::
+PyParser_SimpleParseFile:int:start::
+
+PyParser_SimpleParseString:struct _node*:::
+PyParser_SimpleParseString:char*:str::
+PyParser_SimpleParseString:int:start::
+
+PyRun_AnyFile:int:::
+PyRun_AnyFile:FILE*:fp::
+PyRun_AnyFile:char*:filename::
+
+PyRun_File:PyObject*::+1:??? -- same as eval_code2()
+PyRun_File:FILE*:fp::
+PyRun_File:char*:filename::
+PyRun_File:int:start::
+PyRun_File:PyObject*:globals:0:
+PyRun_File:PyObject*:locals:0:
+
+PyRun_FileEx:PyObject*::+1:??? -- same as eval_code2()
+PyRun_FileEx:FILE*:fp::
+PyRun_FileEx:char*:filename::
+PyRun_FileEx:int:start::
+PyRun_FileEx:PyObject*:globals:0:
+PyRun_FileEx:PyObject*:locals:0:
+PyRun_FileEx:int:closeit::
+
+PyRun_FileFlags:PyObject*::+1:??? -- same as eval_code2()
+PyRun_FileFlags:FILE*:fp::
+PyRun_FileFlags:char*:filename::
+PyRun_FileFlags:int:start::
+PyRun_FileFlags:PyObject*:globals:0:
+PyRun_FileFlags:PyObject*:locals:0:
+PyRun_FileFlags:PyCompilerFlags*:flags::
+
+PyRun_FileExFlags:PyObject*::+1:??? -- same as eval_code2()
+PyRun_FileExFlags:FILE*:fp::
+PyRun_FileExFlags:char*:filename::
+PyRun_FileExFlags:int:start::
+PyRun_FileExFlags:PyObject*:globals:0:
+PyRun_FileExFlags:PyObject*:locals:0:
+PyRun_FileExFlags:int:closeit::
+PyRun_FileExFlags:PyCompilerFlags*:flags::
+
+PyRun_InteractiveLoop:int:::
+PyRun_InteractiveLoop:FILE*:fp::
+PyRun_InteractiveLoop:char*:filename::
+
+PyRun_InteractiveOne:int:::
+PyRun_InteractiveOne:FILE*:fp::
+PyRun_InteractiveOne:char*:filename::
+
+PyRun_SimpleFile:int:::
+PyRun_SimpleFile:FILE*:fp::
+PyRun_SimpleFile:char*:filename::
+
+PyRun_SimpleString:int:::
+PyRun_SimpleString:char*:command::
+
+PyRun_String:PyObject*::+1:??? -- same as eval_code2()
+PyRun_String:char*:str::
+PyRun_String:int:start::
+PyRun_String:PyObject*:globals:0:
+PyRun_String:PyObject*:locals:0:
+
+PyRun_StringFlags:PyObject*::+1:??? -- same as eval_code2()
+PyRun_StringFlags:char*:str::
+PyRun_StringFlags:int:start::
+PyRun_StringFlags:PyObject*:globals:0:
+PyRun_StringFlags:PyObject*:locals:0:
+PyRun_StringFlags:PyCompilerFlags*:flags::
+
+PySeqIter_New:PyObject*::+1:
+PySeqIter_New:PyObject*:seq::
+
+PySequence_Check:int:::
+PySequence_Check:PyObject*:o:0:
+
+PySequence_Concat:PyObject*::+1:
+PySequence_Concat:PyObject*:o1:0:
+PySequence_Concat:PyObject*:o2:0:
+
+PySequence_Count:int:::
+PySequence_Count:PyObject*:o:0:
+PySequence_Count:PyObject*:value:0:
+
+PySequence_DelItem:int:::
+PySequence_DelItem:PyObject*:o:0:
+PySequence_DelItem:int:i::
+
+PySequence_DelSlice:int:::
+PySequence_DelSlice:PyObject*:o:0:
+PySequence_DelSlice:int:i1::
+PySequence_DelSlice:int:i2::
+
+PySequence_Fast:PyObject*::+1:
+PySequence_Fast:PyObject*:v:0:
+PySequence_Fast:const char*:m::
+
+PySequence_Fast_GET_ITEM:PyObject*::0:
+PySequence_Fast_GET_ITEM:PyObject*:o:0:
+PySequence_Fast_GET_ITEM:int:i::
+
+PySequence_GetItem:PyObject*::+1:
+PySequence_GetItem:PyObject*:o:0:
+PySequence_GetItem:int:i::
+
+PySequence_GetSlice:PyObject*::+1:
+PySequence_GetSlice:PyObject*:o:0:
+PySequence_GetSlice:int:i1::
+PySequence_GetSlice:int:i2::
+
+PySequence_In:int:::
+PySequence_In:PyObject*:o:0:
+PySequence_In:PyObject*:value:0:
+
+PySequence_Index:int:::
+PySequence_Index:PyObject*:o:0:
+PySequence_Index:PyObject*:value:0:
+
+PySequence_InPlaceConcat:PyObject*::+1:
+PySequence_InPlaceConcat:PyObject*:s:0:
+PySequence_InPlaceConcat:PyObject*:o:0:
+
+PySequence_InPlaceRepeat:PyObject*::+1:
+PySequence_InPlaceRepeat:PyObject*:s:0:
+PySequence_InPlaceRepeat:PyObject*:o:0:
+
+PySequence_ITEM:PyObject*::+1:
+PySequence_ITEM:PyObject*:o:0:
+PySequence_ITEM:int:i::
+
+PySequence_Repeat:PyObject*::+1:
+PySequence_Repeat:PyObject*:o:0:
+PySequence_Repeat:int:count::
+
+PySequence_SetItem:int:::
+PySequence_SetItem:PyObject*:o:0:
+PySequence_SetItem:int:i::
+PySequence_SetItem:PyObject*:v:+1:
+
+PySequence_SetSlice:int:::
+PySequence_SetSlice:PyObject*:o:0:
+PySequence_SetSlice:int:i1::
+PySequence_SetSlice:int:i2::
+PySequence_SetSlice:PyObject*:v:+1:
+
+PySequence_List:PyObject*::+1:
+PySequence_List:PyObject*:o:0:
+
+PySequence_Tuple:PyObject*::+1:
+PySequence_Tuple:PyObject*:o:0:
+
+PySet_Append:int:::
+PySet_Append:PyObject*:set:0:
+PySet_Append:PyObject*:key:+1:
+
+PySet_Contains:int:::
+PySet_Contains:PyObject*:anyset:0:
+PySet_Contains:PyObject*:key:0:
+
+PySet_Discard:int:::
+PySet_Discard:PyObject*:set:0:
+PySet_Discard:PyObject*:key:-1:no effect if key not found
+
+PySet_New:PyObject*::+1:
+PySet_New:PyObject*:iterable:0:
+
+PySet_Pop:PyObject*::+1:or returns NULL and raises KeyError if set is empty
+PySet_Pop:PyObject*:set:0:
+
+PySet_Size:int:::
+PySet_Size:PyObject*:anyset:0:
+
+PySlice_Check:int:::
+PySlice_Check:PyObject*:ob:0:
+
+PySlice_New:PyObject*::+1:
+PySlice_New:PyObject*:start:0:
+PySlice_New:PyObject*:stop:0:
+PySlice_New:PyObject*:step:0:
+
+PyString_AS_STRING:char*:::
+PyString_AS_STRING:PyObject*:string:0:
+
+PyString_AsDecodedObject:PyObject*::+1:
+PyString_AsDecodedObject:PyObject*:str:0:
+PyString_AsDecodedObject:const char*:encoding::
+PyString_AsDecodedObject:const char*:errors::
+
+PyString_AsEncodedObject:PyObject*::+1:
+PyString_AsEncodedObject:PyObject*:str:0:
+PyString_AsEncodedObject:const char*:encoding::
+PyString_AsEncodedObject:const char*:errors::
+
+PyString_AsString:char*:::
+PyString_AsString:PyObject*:string:0:
+
+PyString_AsStringAndSize:int:::
+PyString_AsStringAndSize:PyObject*:obj:0:
+PyString_AsStringAndSize:char**:buffer::
+PyString_AsStringAndSize:int*:length::
+
+PyString_Check:int:::
+PyString_Check:PyObject*:o:0:
+
+PyString_Concat:void:::
+PyString_Concat:PyObject**:string:0:??? -- replaces w/ new string or NULL
+PyString_Concat:PyObject*:newpart:0:
+
+PyString_ConcatAndDel:void:::
+PyString_ConcatAndDel:PyObject**:string:0:??? -- replaces w/ new string or NULL
+PyString_ConcatAndDel:PyObject*:newpart:-1:
+
+PyString_Format:PyObject*::+1:
+PyString_Format:PyObject*:format:0:
+PyString_Format:PyObject*:args:0:
+
+PyString_FromString:PyObject*::+1:
+PyString_FromString:const char*:v::
+
+PyString_FromStringAndSize:PyObject*::+1:
+PyString_FromStringAndSize:const char*:v::
+PyString_FromStringAndSize:int:len::
+
+PyString_FromFormat:PyObject*::+1:
+PyString_FromFormat:const char*:format::
+PyString_FromFormat::...::
+
+PyString_FromFormatV:PyObject*::+1:
+PyString_FromFormatV:const char*:format::
+PyString_FromFormatV:va_list:vargs::
+
+PyString_GET_SIZE:int:::
+PyString_GET_SIZE:PyObject*:string:0:
+
+PyString_InternFromString:PyObject*::+1:
+PyString_InternFromString:const char*:v::
+
+PyString_InternInPlace:void:::
+PyString_InternInPlace:PyObject**:string:+1:???
+
+PyString_Size:int:::
+PyString_Size:PyObject*:string:0:
+
+PyString_Decode:PyObject*::+1:
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+PyString_AsEncodedString:const char*:errors::
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+PySys_SetArgv:int:argc::
+PySys_SetArgv:char**:argv::
+
+PyThreadState_Clear:void:::
+PyThreadState_Clear:PyThreadState*:tstate::
+
+PyThreadState_Delete:void:::
+PyThreadState_Delete:PyThreadState*:tstate::
+
+PyThreadState_Get:PyThreadState*:::
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+PyThreadState_GetDict:PyObject*::0:
+
+PyThreadState_New:PyThreadState*:::
+PyThreadState_New:PyInterpreterState*:interp::
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+PyThreadState_Swap:PyThreadState*:::
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+PyTime_FromTime:PyObject*::+1:
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+PyTuple_GET_ITEM:PyObject*::0:
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+PyTuple_GetItem:PyObject*::0:
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+PyTuple_Pack:PyObject*::+1:
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+PyTuple_Pack:PyObject*:...:0:
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+PyTuple_SET_ITEM:PyObject*:o:0:
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+PyType_GenericAlloc:int:nitems:0:
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+PyType_GenericNew:PyObject*::+1:
+PyType_GenericNew:PyObject*:type:0:
+PyType_GenericNew:PyObject*:args:0:
+PyType_GenericNew:PyObject*:kwds:0:
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+PyUnicode_Check:int:::
+PyUnicode_Check:PyObject*:o:0:
+
+PyUnicode_GET_SIZE:int:::
+PyUnicode_GET_SIZE:PyObject*:o:0:
+
+PyUnicode_GET_DATA_SIZE:int:::
+PyUnicode_GET_DATA_SIZE:PyObject*:o:0:
+
+PyUnicode_AS_UNICODE:Py_UNICODE*:::
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+
+PyUnicode_AS_DATA:const char*:::
+PyUnicode_AS_DATA:PyObject*:o:0:
+
+Py_UNICODE_ISSPACE:int:::
+Py_UNICODE_ISSPACE:Py_UNICODE:ch::
+
+Py_UNICODE_ISLOWER:int:::
+Py_UNICODE_ISLOWER:Py_UNICODE:ch::
+
+Py_UNICODE_ISUPPER:int:::
+Py_UNICODE_ISUPPER:Py_UNICODE:ch::
+
+Py_UNICODE_ISTITLE:int:::
+Py_UNICODE_ISTITLE:Py_UNICODE:ch::
+
+Py_UNICODE_ISLINEBREAK:int:::
+Py_UNICODE_ISLINEBREAK:Py_UNICODE:ch::
+
+Py_UNICODE_ISDECIMAL:int:::
+Py_UNICODE_ISDECIMAL:Py_UNICODE:ch::
+
+Py_UNICODE_ISDIGIT:int:::
+Py_UNICODE_ISDIGIT:Py_UNICODE:ch::
+
+Py_UNICODE_ISNUMERIC:int:::
+Py_UNICODE_ISNUMERIC:Py_UNICODE:ch::
+
+Py_UNICODE_TOLOWER:Py_UNICODE:::
+Py_UNICODE_TOLOWER:Py_UNICODE:ch::
+
+Py_UNICODE_TOUPPER:Py_UNICODE:::
+Py_UNICODE_TOUPPER:Py_UNICODE:ch::
+
+Py_UNICODE_TOTITLE:Py_UNICODE:::
+Py_UNICODE_TOTITLE:Py_UNICODE:ch::
+
+Py_UNICODE_TODECIMAL:int:::
+Py_UNICODE_TODECIMAL:Py_UNICODE:ch::
+
+Py_UNICODE_TODIGIT:int:::
+Py_UNICODE_TODIGIT:Py_UNICODE:ch::
+
+Py_UNICODE_TONUMERIC:double:::
+Py_UNICODE_TONUMERIC:Py_UNICODE:ch::
+
+PyUnicode_FromUnicode:PyObject*::+1:
+PyUnicode_FromUnicode:const Py_UNICODE*:u::
+PyUnicode_FromUnicode:int:size::
+
+PyUnicode_AsUnicode:Py_UNICODE*:::
+PyUnicode_AsUnicode:PyObject :*unicode:0:
+
+PyUnicode_GetSize:int:::
+PyUnicode_GetSize:PyObject :*unicode:0:
+
+PyUnicode_FromObject:PyObject*::+1:
+PyUnicode_FromObject:PyObject*:*obj:0:
+
+PyUnicode_FromEncodedObject:PyObject*::+1:
+PyUnicode_FromEncodedObject:PyObject*:*obj:0:
+PyUnicode_FromEncodedObject:const char*:encoding::
+PyUnicode_FromEncodedObject:const char*:errors::
+
+PyUnicode_FromWideChar:PyObject*::+1:
+PyUnicode_FromWideChar:const wchar_t*:w::
+PyUnicode_FromWideChar:int:size::
+
+PyUnicode_AsWideChar:int:::
+PyUnicode_AsWideChar:PyObject*:*unicode:0:
+PyUnicode_AsWideChar:wchar_t*:w::
+PyUnicode_AsWideChar:int:size::
+
+PyUnicode_Decode:PyObject*::+1:
+PyUnicode_Decode:const char*:s::
+PyUnicode_Decode:int:size::
+PyUnicode_Decode:const char*:encoding::
+PyUnicode_Decode:const char*:errors::
+
+PyUnicode_DecodeUTF16Stateful:PyObject*::+1:
+PyUnicode_DecodeUTF16Stateful:const char*:s::
+PyUnicode_DecodeUTF16Stateful:int:size::
+PyUnicode_DecodeUTF16Stateful:const char*:errors::
+PyUnicode_DecodeUTF16Stateful:int*:byteorder::
+PyUnicode_DecodeUTF16Stateful:int*:consumed::
+
+PyUnicode_DecodeUTF8Stateful:PyObject*::+1:
+PyUnicode_DecodeUTF8Stateful:const char*:s::
+PyUnicode_DecodeUTF8Stateful:int:size::
+PyUnicode_DecodeUTF8Stateful:const char*:errors::
+PyUnicode_DecodeUTF8Stateful:int*:consumed::
+
+PyUnicode_Encode:PyObject*::+1:
+PyUnicode_Encode:const Py_UNICODE*:s::
+PyUnicode_Encode:int:size::
+PyUnicode_Encode:const char*:encoding::
+PyUnicode_Encode:const char*:errors::
+
+PyUnicode_AsEncodedString:PyObject*::+1:
+PyUnicode_AsEncodedString:PyObject*:unicode::
+PyUnicode_AsEncodedString:const char*:encoding::
+PyUnicode_AsEncodedString:const char*:errors::
+
+PyUnicode_DecodeUTF8:PyObject*::+1:
+PyUnicode_DecodeUTF8:const char*:s::
+PyUnicode_DecodeUTF8:int:size::
+PyUnicode_DecodeUTF8:const char*:errors::
+
+PyUnicode_EncodeUTF8:PyObject*::+1:
+PyUnicode_EncodeUTF8:const Py_UNICODE*:s::
+PyUnicode_EncodeUTF8:int:size::
+PyUnicode_EncodeUTF8:const char*:errors::
+
+PyUnicode_AsUTF8String:PyObject*::+1:
+PyUnicode_AsUTF8String:PyObject*:unicode::
+
+PyUnicode_DecodeUTF16:PyObject*::+1:
+PyUnicode_DecodeUTF16:const char*:s::
+PyUnicode_DecodeUTF16:int:size::
+PyUnicode_DecodeUTF16:const char*:errors::
+PyUnicode_DecodeUTF16:int*:byteorder::
+
+PyUnicode_EncodeUTF16:PyObject*::+1:
+PyUnicode_EncodeUTF16:const Py_UNICODE*:s::
+PyUnicode_EncodeUTF16:int:size::
+PyUnicode_EncodeUTF16:const char*:errors::
+PyUnicode_EncodeUTF16:int:byteorder::
+
+PyUnicode_AsUTF16String:PyObject*::+1:
+PyUnicode_AsUTF16String:PyObject*:unicode::
+
+PyUnicode_DecodeUnicodeEscape:PyObject*::+1:
+PyUnicode_DecodeUnicodeEscape:const char*:s::
+PyUnicode_DecodeUnicodeEscape:int:size::
+PyUnicode_DecodeUnicodeEscape:const char*:errors::
+
+PyUnicode_EncodeUnicodeEscape:PyObject*::+1:
+PyUnicode_EncodeUnicodeEscape:const Py_UNICODE*:s::
+PyUnicode_EncodeUnicodeEscape:int:size::
+PyUnicode_EncodeUnicodeEscape:const char*:errors::
+
+PyUnicode_AsUnicodeEscapeString:PyObject*::+1:
+PyUnicode_AsUnicodeEscapeString:PyObject*:unicode::
+
+PyUnicode_DecodeRawUnicodeEscape:PyObject*::+1:
+PyUnicode_DecodeRawUnicodeEscape:const char*:s::
+PyUnicode_DecodeRawUnicodeEscape:int:size::
+PyUnicode_DecodeRawUnicodeEscape:const char*:errors::
+
+PyUnicode_EncodeRawUnicodeEscape:PyObject*::+1:
+PyUnicode_EncodeRawUnicodeEscape:const Py_UNICODE*:s::
+PyUnicode_EncodeRawUnicodeEscape:int:size::
+PyUnicode_EncodeRawUnicodeEscape:const char*:errors::
+
+PyUnicode_AsRawUnicodeEscapeString:PyObject*::+1:
+PyUnicode_AsRawUnicodeEscapeString:PyObject*:unicode::
+
+PyUnicode_DecodeLatin1:PyObject*::+1:
+PyUnicode_DecodeLatin1:const char*:s::
+PyUnicode_DecodeLatin1:int:size::
+PyUnicode_DecodeLatin1:const char*:errors::
+
+PyUnicode_EncodeLatin1:PyObject*::+1:
+PyUnicode_EncodeLatin1:const Py_UNICODE*:s::
+PyUnicode_EncodeLatin1:int:size::
+PyUnicode_EncodeLatin1:const char*:errors::
+
+PyUnicode_AsLatin1String:PyObject*::+1:
+PyUnicode_AsLatin1String:PyObject*:unicode::
+
+PyUnicode_DecodeASCII:PyObject*::+1:
+PyUnicode_DecodeASCII:const char*:s::
+PyUnicode_DecodeASCII:int:size::
+PyUnicode_DecodeASCII:const char*:errors::
+
+PyUnicode_EncodeASCII:PyObject*::+1:
+PyUnicode_EncodeASCII:const Py_UNICODE*:s::
+PyUnicode_EncodeASCII:int:size::
+PyUnicode_EncodeASCII:const char*:errors::
+
+PyUnicode_AsASCIIString:PyObject*::+1:
+PyUnicode_AsASCIIString:PyObject*:unicode::
+
+PyUnicode_DecodeCharmap:PyObject*::+1:
+PyUnicode_DecodeCharmap:const char*:s::
+PyUnicode_DecodeCharmap:int:size::
+PyUnicode_DecodeCharmap:PyObject*:mapping:0:
+PyUnicode_DecodeCharmap:const char*:errors::
+
+PyUnicode_EncodeCharmap:PyObject*::+1:
+PyUnicode_EncodeCharmap:const Py_UNICODE*:s::
+PyUnicode_EncodeCharmap:int:size::
+PyUnicode_EncodeCharmap:PyObject*:mapping:0:
+PyUnicode_EncodeCharmap:const char*:errors::
+
+PyUnicode_AsCharmapString:PyObject*::+1:
+PyUnicode_AsCharmapString:PyObject*:unicode:0:
+PyUnicode_AsCharmapString:PyObject*:mapping:0:
+
+PyUnicode_TranslateCharmap:PyObject*::+1:
+PyUnicode_TranslateCharmap:const Py_UNICODE*:s::
+PyUnicode_TranslateCharmap:int:size::
+PyUnicode_TranslateCharmap:PyObject*:table:0:
+PyUnicode_TranslateCharmap:const char*:errors::
+
+PyUnicode_DecodeMBCS:PyObject*::+1:
+PyUnicode_DecodeMBCS:const char*:s::
+PyUnicode_DecodeMBCS:int:size::
+PyUnicode_DecodeMBCS:const char*:errors::
+
+PyUnicode_EncodeMBCS:PyObject*::+1:
+PyUnicode_EncodeMBCS:const Py_UNICODE*:s::
+PyUnicode_EncodeMBCS:int:size::
+PyUnicode_EncodeMBCS:const char*:errors::
+
+PyUnicode_AsMBCSString:PyObject*::+1:
+PyUnicode_AsMBCSString:PyObject*:unicode::
+
+PyUnicode_Concat:PyObject*::+1:
+PyUnicode_Concat:PyObject*:left:0:
+PyUnicode_Concat:PyObject*:right:0:
+
+PyUnicode_Split:PyObject*::+1:
+PyUnicode_Split:PyObject*:left:0:
+PyUnicode_Split:PyObject*:right:0:
+PyUnicode_Split:int:maxsplit::
+
+PyUnicode_Splitlines:PyObject*::+1:
+PyUnicode_Splitlines:PyObject*:s:0:
+PyUnicode_Splitlines:int:maxsplit::
+
+PyUnicode_Translate:PyObject*::+1:
+PyUnicode_Translate:PyObject*:str:0:
+PyUnicode_Translate:PyObject*:table:0:
+PyUnicode_Translate:const char*:errors::
+
+PyUnicode_Join:PyObject*::+1:
+PyUnicode_Join:PyObject*:separator:0:
+PyUnicode_Join:PyObject*:seq:0:
+
+PyUnicode_Tailmatch:PyObject*::+1:
+PyUnicode_Tailmatch:PyObject*:str:0:
+PyUnicode_Tailmatch:PyObject*:substr:0:
+PyUnicode_Tailmatch:int:start::
+PyUnicode_Tailmatch:int:end::
+PyUnicode_Tailmatch:int:direction::
+
+PyUnicode_Find:int:::
+PyUnicode_Find:PyObject*:str:0:
+PyUnicode_Find:PyObject*:substr:0:
+PyUnicode_Find:int:start::
+PyUnicode_Find:int:end::
+PyUnicode_Find:int:direction::
+
+PyUnicode_Count:int:::
+PyUnicode_Count:PyObject*:str:0:
+PyUnicode_Count:PyObject*:substr:0:
+PyUnicode_Count:int:start::
+PyUnicode_Count:int:end::
+
+PyUnicode_Replace:PyObject*::+1:
+PyUnicode_Replace:PyObject*:str:0:
+PyUnicode_Replace:PyObject*:substr:0:
+PyUnicode_Replace:PyObject*:replstr:0:
+PyUnicode_Replace:int:maxcount::
+
+PyUnicode_Compare:int:::
+PyUnicode_Compare:PyObject*:left:0:
+PyUnicode_Compare:PyObject*:right:0:
+
+PyUnicode_Format:PyObject*::+1:
+PyUnicode_Format:PyObject*:format:0:
+PyUnicode_Format:PyObject*:args:0:
+
+PyUnicode_Contains:int:::
+PyUnicode_Contains:PyObject*:container:0:
+PyUnicode_Contains:PyObject*:element:0:
+
+PyWeakref_GET_OBJECT:PyObject*::0:
+PyWeakref_GET_OBJECT:PyObject*:ref:0:
+
+PyWeakref_GetObject:PyObject*::0:
+PyWeakref_GetObject:PyObject*:ref:0:
+
+PyWeakref_NewProxy:PyObject*::+1:
+PyWeakref_NewProxy:PyObject*:ob:0:
+PyWeakref_NewProxy:PyObject*:callback:0:
+
+PyWeakref_NewRef:PyObject*::+1:
+PyWeakref_NewRef:PyObject*:ob:0:
+PyWeakref_NewRef:PyObject*:callback:0:
+
+PyWrapper_New:PyObject*::+1:
+PyWrapper_New:PyObject*:d:0:
+PyWrapper_New:PyObject*:self:0:
+
+Py_AtExit:int:::
+Py_AtExit:void (*)():func::
+
+Py_BuildValue:PyObject*::+1:
+Py_BuildValue:char*:format::
+
+Py_CompileString:PyObject*::+1:
+Py_CompileString:char*:str::
+Py_CompileString:char*:filename::
+Py_CompileString:int:start::
+
+Py_CompileStringFlags:PyObject*::+1:
+Py_CompileStringFlags:char*:str::
+Py_CompileStringFlags:char*:filename::
+Py_CompileStringFlags:int:start::
+Py_CompileStringFlags:PyCompilerFlags*:flags::
+
+Py_DECREF:void:::
+Py_DECREF:PyObject*:o:-1:
+
+Py_EndInterpreter:void:::
+Py_EndInterpreter:PyThreadState*:tstate::
+
+Py_Exit:void:::
+Py_Exit:int:status::
+
+Py_FatalError:void:::
+Py_FatalError:char*:message::
+
+Py_FdIsInteractive:int:::
+Py_FdIsInteractive:FILE*:fp::
+Py_FdIsInteractive:char*:filename::
+
+Py_Finalize:void:::
+
+Py_FindMethod:PyObject*::+1:
+Py_FindMethod:PyMethodDef[]:methods::
+Py_FindMethod:PyObject*:self:+1:
+Py_FindMethod:char*:name::
+
+Py_GetBuildInfoconst:char*:::
+
+Py_GetCompilerconst:char*:::
+
+Py_GetCopyrightconst:char*:::
+
+Py_GetExecPrefix:char*:::
+
+Py_GetPath:char*:::
+
+Py_GetPlatformconst:char*:::
+
+Py_GetPrefix:char*:::
+
+Py_GetProgramFullPath:char*:::
+
+Py_GetProgramName:char*:::
+
+Py_GetVersionconst:char*:::
+
+Py_INCREF:void:::
+Py_INCREF:PyObject*:o:+1:
+
+Py_Initialize:void:::
+
+Py_IsInitialized:int:::
+
+Py_NewInterpreter:PyThreadState*:::
+
+Py_SetProgramName:void:::
+Py_SetProgramName:char*:name::
+
+Py_XDECREF:void:::
+Py_XDECREF:PyObject*:o:-1:if o is not NULL
+
+Py_XINCREF:void:::
+Py_XINCREF:PyObject*:o:+1:if o is not NULL
+
+_PyImport_FindExtension:PyObject*::0:??? see PyImport_AddModule
+_PyImport_FindExtension:char*:::
+_PyImport_FindExtension:char*:::
+
+_PyImport_Fini:void:::
+
+_PyImport_FixupExtension:PyObject*:::???
+_PyImport_FixupExtension:char*:::
+_PyImport_FixupExtension:char*:::
+
+_PyImport_Init:void:::
+
+_PyObject_Del:void:::
+_PyObject_Del:PyObject*:op:0:
+
+_PyObject_New:PyObject*::+1:
+_PyObject_New:PyTypeObject*:type:0:
+
+_PyObject_NewVar:PyObject*::+1:
+_PyObject_NewVar:PyTypeObject*:type:0:
+_PyObject_NewVar:int:size::
+
+_PyString_Resize:int:::
+_PyString_Resize:PyObject**:string:+1:
+_PyString_Resize:int:newsize::
+
+_PyTuple_Resize:int:::
+_PyTuple_Resize:PyTupleObject**:p:+1:
+_PyTuple_Resize:int:new::
+
+_Py_c_diff:Py_complex:::
+_Py_c_diff:Py_complex:left::
+_Py_c_diff:Py_complex:right::
+
+_Py_c_neg:Py_complex:::
+_Py_c_neg:Py_complex:complex::
+
+_Py_c_pow:Py_complex:::
+_Py_c_pow:Py_complex:num::
+_Py_c_pow:Py_complex:exp::
+
+_Py_c_prod:Py_complex:::
+_Py_c_prod:Py_complex:left::
+_Py_c_prod:Py_complex:right::
+
+_Py_c_quot:Py_complex:::
+_Py_c_quot:Py_complex:dividend::
+_Py_c_quot:Py_complex:divisor::
+
+_Py_c_sum:Py_complex:::
+_Py_c_sum:Py_complex:left::
+_Py_c_sum:Py_complex:right::
diff --git a/Doc/distutils/apiref.rst b/Doc/distutils/apiref.rst
new file mode 100644
index 0000000000..c8e57fde0b
--- /dev/null
+++ b/Doc/distutils/apiref.rst
@@ -0,0 +1,1976 @@
+.. _api-reference:
+
+*************
+API Reference
+*************
+
+
+:mod:`distutils.core` --- Core Distutils functionality
+======================================================
+
+.. module:: distutils.core
+ :synopsis: The core Distutils functionality
+
+
+The :mod:`distutils.core` module is the only module that needs to be installed
+to use the Distutils. It provides the :func:`setup` (which is called from the
+setup script). Indirectly provides the :class:`distutils.dist.Distribution` and
+:class:`distutils.cmd.Command` class.
+
+
+.. function:: setup(arguments)
+
+ The basic do-everything function that does most everything you could ever ask
+ for from a Distutils method. See XXXXX
+
+ The setup function takes a large number of arguments. These are laid out in the
+ following table.
+
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | argument name | value | type |
+ +====================+================================+=============================================================+
+ | *name* | The name of the package | a string |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *version* | The version number of the | See :mod:`distutils.version` |
+ | | package | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *description* | A single line describing the | a string |
+ | | package | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *long_description* | Longer description of the | a string |
+ | | package | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *author* | The name of the package author | a string |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *author_email* | The email address of the | a string |
+ | | package author | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *maintainer* | The name of the current | a string |
+ | | maintainer, if different from | |
+ | | the author | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *maintainer_email* | The email address of the | |
+ | | current maintainer, if | |
+ | | different from the author | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *url* | A URL for the package | a URL |
+ | | (homepage) | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *download_url* | A URL to download the package | a URL |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *packages* | A list of Python packages that | a list of strings |
+ | | distutils will manipulate | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *py_modules* | A list of Python modules that | a list of strings |
+ | | distutils will manipulate | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *scripts* | A list of standalone script | a list of strings |
+ | | files to be built and | |
+ | | installed | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *ext_modules* | A list of Python extensions to | A list of instances of |
+ | | be built | :class:`distutils.core.Extension` |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *classifiers* | A list of categories for the | The list of available |
+ | | package | categorizations is at |
+ | | | http://cheeseshop.python.org/pypi?:action=list_classifiers. |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *distclass* | the :class:`Distribution` | A subclass of |
+ | | class to use | :class:`distutils.core.Distribution` |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *script_name* | The name of the setup.py | a string |
+ | | script - defaults to | |
+ | | ``sys.argv[0]`` | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *script_args* | Arguments to supply to the | a list of strings |
+ | | setup script | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *options* | default options for the setup | a string |
+ | | script | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *license* | The license for the package | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *keywords* | Descriptive meta-data. See | |
+ | | :pep:`314` | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *platforms* | | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+ | *cmdclass* | A mapping of command names to | a dictionary |
+ | | :class:`Command` subclasses | |
+ +--------------------+--------------------------------+-------------------------------------------------------------+
+
+
+.. function:: run_setup(script_name[, script_args=None, stop_after='run'])
+
+ Run a setup script in a somewhat controlled environment, and return the
+ :class:`distutils.dist.Distribution` instance that drives things. This is
+ useful if you need to find out the distribution meta-data (passed as keyword
+ args from *script* to :func:`setup`), or the contents of the config files or
+ command-line.
+
+ *script_name* is a file that will be read and run with :func:`exec`. ``sys.argv[0]``
+ will be replaced with *script* for the duration of the call. *script_args* is a
+ list of strings; if supplied, ``sys.argv[1:]`` will be replaced by *script_args*
+ for the duration of the call.
+
+ *stop_after* tells :func:`setup` when to stop processing; possible values:
+
+ +---------------+---------------------------------------------+
+ | value | description |
+ +===============+=============================================+
+ | *init* | Stop after the :class:`Distribution` |
+ | | instance has been created and populated |
+ | | with the keyword arguments to :func:`setup` |
+ +---------------+---------------------------------------------+
+ | *config* | Stop after config files have been parsed |
+ | | (and their data stored in the |
+ | | :class:`Distribution` instance) |
+ +---------------+---------------------------------------------+
+ | *commandline* | Stop after the command-line |
+ | | (``sys.argv[1:]`` or *script_args*) have |
+ | | been parsed (and the data stored in the |
+ | | :class:`Distribution` instance.) |
+ +---------------+---------------------------------------------+
+ | *run* | Stop after all commands have been run (the |
+ | | same as if :func:`setup` had been called |
+ | | in the usual way). This is the default |
+ | | value. |
+ +---------------+---------------------------------------------+
+
+In addition, the :mod:`distutils.core` module exposed a number of classes that
+live elsewhere.
+
+* :class:`Extension` from :mod:`distutils.extension`
+
+* :class:`Command` from :mod:`distutils.cmd`
+
+* :class:`Distribution` from :mod:`distutils.dist`
+
+A short description of each of these follows, but see the relevant module for
+the full reference.
+
+
+.. class:: Extension
+
+ The Extension class describes a single C or C++extension module in a setup
+ script. It accepts the following keyword arguments in its constructor
+
+ +------------------------+--------------------------------+---------------------------+
+ | argument name | value | type |
+ +========================+================================+===========================+
+ | *name* | the full name of the | string |
+ | | extension, including any | |
+ | | packages --- ie. *not* a | |
+ | | filename or pathname, but | |
+ | | Python dotted name | |
+ +------------------------+--------------------------------+---------------------------+
+ | *sources* | list of source filenames, | string |
+ | | relative to the distribution | |
+ | | root (where the setup script | |
+ | | lives), in Unix form (slash- | |
+ | | separated) for portability. | |
+ | | Source files may be C, C++, | |
+ | | SWIG (.i), platform-specific | |
+ | | resource files, or whatever | |
+ | | else is recognized by the | |
+ | | :command:`build_ext` command | |
+ | | as source for a Python | |
+ | | extension. | |
+ +------------------------+--------------------------------+---------------------------+
+ | *include_dirs* | list of directories to search | string |
+ | | for C/C++ header files (in | |
+ | | Unix form for portability) | |
+ +------------------------+--------------------------------+---------------------------+
+ | *define_macros* | list of macros to define; each | (string,string) tuple or |
+ | | macro is defined using a | (name,``None``) |
+ | | 2-tuple, where 'value' is | |
+ | | either the string to define it | |
+ | | to or ``None`` to define it | |
+ | | without a particular value | |
+ | | (equivalent of ``#define FOO`` | |
+ | | in source or :option:`-DFOO` | |
+ | | on Unix C compiler command | |
+ | | line) | |
+ +------------------------+--------------------------------+---------------------------+
+ | *undef_macros* | list of macros to undefine | string |
+ | | explicitly | |
+ +------------------------+--------------------------------+---------------------------+
+ | *library_dirs* | list of directories to search | string |
+ | | for C/C++ libraries at link | |
+ | | time | |
+ +------------------------+--------------------------------+---------------------------+
+ | *libraries* | list of library names (not | string |
+ | | filenames or paths) to link | |
+ | | against | |
+ +------------------------+--------------------------------+---------------------------+
+ | *runtime_library_dirs* | list of directories to search | string |
+ | | for C/C++ libraries at run | |
+ | | time (for shared extensions, | |
+ | | this is when the extension is | |
+ | | loaded) | |
+ +------------------------+--------------------------------+---------------------------+
+ | *extra_objects* | list of extra files to link | string |
+ | | with (eg. object files not | |
+ | | implied by 'sources', static | |
+ | | library that must be | |
+ | | explicitly specified, binary | |
+ | | resource files, etc.) | |
+ +------------------------+--------------------------------+---------------------------+
+ | *extra_compile_args* | any extra platform- and | string |
+ | | compiler-specific information | |
+ | | to use when compiling the | |
+ | | source files in 'sources'. For | |
+ | | platforms and compilers where | |
+ | | a command line makes sense, | |
+ | | this is typically a list of | |
+ | | command-line arguments, but | |
+ | | for other platforms it could | |
+ | | be anything. | |
+ +------------------------+--------------------------------+---------------------------+
+ | *extra_link_args* | any extra platform- and | string |
+ | | compiler-specific information | |
+ | | to use when linking object | |
+ | | files together to create the | |
+ | | extension (or to create a new | |
+ | | static Python interpreter). | |
+ | | Similar interpretation as for | |
+ | | 'extra_compile_args'. | |
+ +------------------------+--------------------------------+---------------------------+
+ | *export_symbols* | list of symbols to be exported | string |
+ | | from a shared extension. Not | |
+ | | used on all platforms, and not | |
+ | | generally necessary for Python | |
+ | | extensions, which typically | |
+ | | export exactly one symbol: | |
+ | | ``init`` + extension_name. | |
+ +------------------------+--------------------------------+---------------------------+
+ | *depends* | list of files that the | string |
+ | | extension depends on | |
+ +------------------------+--------------------------------+---------------------------+
+ | *language* | extension language (i.e. | string |
+ | | ``'c'``, ``'c++'``, | |
+ | | ``'objc'``). Will be detected | |
+ | | from the source extensions if | |
+ | | not provided. | |
+ +------------------------+--------------------------------+---------------------------+
+
+
+.. class:: Distribution
+
+ A :class:`Distribution` describes how to build, install and package up a Python
+ software package.
+
+ See the :func:`setup` function for a list of keyword arguments accepted by the
+ Distribution constructor. :func:`setup` creates a Distribution instance.
+
+
+.. class:: Command
+
+ A :class:`Command` class (or rather, an instance of one of its subclasses)
+ implement a single distutils command.
+
+
+:mod:`distutils.ccompiler` --- CCompiler base class
+===================================================
+
+.. module:: distutils.ccompiler
+ :synopsis: Abstract CCompiler class
+
+
+This module provides the abstract base class for the :class:`CCompiler`
+classes. A :class:`CCompiler` instance can be used for all the compile and
+link steps needed to build a single project. Methods are provided to set
+options for the compiler --- macro definitions, include directories, link path,
+libraries and the like.
+
+This module provides the following functions.
+
+
+.. function:: gen_lib_options(compiler, library_dirs, runtime_library_dirs, libraries)
+
+ Generate linker options for searching library directories and linking with
+ specific libraries. *libraries* and *library_dirs* are, respectively, lists of
+ library names (not filenames!) and search directories. Returns a list of
+ command-line options suitable for use with some compiler (depending on the two
+ format strings passed in).
+
+
+.. function:: gen_preprocess_options(macros, include_dirs)
+
+ Generate C pre-processor options (:option:`-D`, :option:`-U`, :option:`-I`) as
+ used by at least two types of compilers: the typical Unix compiler and Visual
+ C++. *macros* is the usual thing, a list of 1- or 2-tuples, where ``(name,)``
+ means undefine (:option:`-U`) macro *name*, and ``(name, value)`` means define
+ (:option:`-D`) macro *name* to *value*. *include_dirs* is just a list of
+ directory names to be added to the header file search path (:option:`-I`).
+ Returns a list of command-line options suitable for either Unix compilers or
+ Visual C++.
+
+
+.. function:: get_default_compiler(osname, platform)
+
+ Determine the default compiler to use for the given platform.
+
+ *osname* should be one of the standard Python OS names (i.e. the ones returned
+ by ``os.name``) and *platform* the common value returned by ``sys.platform`` for
+ the platform in question.
+
+ The default values are ``os.name`` and ``sys.platform`` in case the parameters
+ are not given.
+
+
+.. function:: new_compiler(plat=None, compiler=None, verbose=0, dry_run=0, force=0)
+
+ Factory function to generate an instance of some CCompiler subclass for the
+ supplied platform/compiler combination. *plat* defaults to ``os.name`` (eg.
+ ``'posix'``, ``'nt'``), and *compiler* defaults to the default compiler for
+ that platform. Currently only ``'posix'`` and ``'nt'`` are supported, and the
+ default compilers are "traditional Unix interface" (:class:`UnixCCompiler`
+ class) and Visual C++(:class:`MSVCCompiler` class). Note that it's perfectly
+ possible to ask for a Unix compiler object under Windows, and a Microsoft
+ compiler object under Unix---if you supply a value for *compiler*, *plat* is
+ ignored.
+
+ .. % Is the posix/nt only thing still true? Mac OS X seems to work, and
+ .. % returns a UnixCCompiler instance. How to document this... hmm.
+
+
+.. function:: show_compilers()
+
+ Print list of available compilers (used by the :option:`--help-compiler` options
+ to :command:`build`, :command:`build_ext`, :command:`build_clib`).
+
+
+.. class:: CCompiler([verbose=0, dry_run=0, force=0])
+
+ The abstract base class :class:`CCompiler` defines the interface that must be
+ implemented by real compiler classes. The class also has some utility methods
+ used by several compiler classes.
+
+ The basic idea behind a compiler abstraction class is that each instance can be
+ used for all the compile/link steps in building a single project. Thus,
+ attributes common to all of those compile and link steps --- include
+ directories, macros to define, libraries to link against, etc. --- are
+ attributes of the compiler instance. To allow for variability in how individual
+ files are treated, most of those attributes may be varied on a per-compilation
+ or per-link basis.
+
+ The constructor for each subclass creates an instance of the Compiler object.
+ Flags are *verbose* (show verbose output), *dry_run* (don't actually execute the
+ steps) and *force* (rebuild everything, regardless of dependencies). All of
+ these flags default to ``0`` (off). Note that you probably don't want to
+ instantiate :class:`CCompiler` or one of its subclasses directly - use the
+ :func:`distutils.CCompiler.new_compiler` factory function instead.
+
+ The following methods allow you to manually alter compiler options for the
+ instance of the Compiler class.
+
+
+ .. method:: CCompiler.add_include_dir(dir)
+
+ Add *dir* to the list of directories that will be searched for header files.
+ The compiler is instructed to search directories in the order in which they are
+ supplied by successive calls to :meth:`add_include_dir`.
+
+
+ .. method:: CCompiler.set_include_dirs(dirs)
+
+ Set the list of directories that will be searched to *dirs* (a list of strings).
+ Overrides any preceding calls to :meth:`add_include_dir`; subsequent calls to
+ :meth:`add_include_dir` add to the list passed to :meth:`set_include_dirs`.
+ This does not affect any list of standard include directories that the compiler
+ may search by default.
+
+
+ .. method:: CCompiler.add_library(libname)
+
+ Add *libname* to the list of libraries that will be included in all links driven
+ by this compiler object. Note that *libname* should \*not\* be the name of a
+ file containing a library, but the name of the library itself: the actual
+ filename will be inferred by the linker, the compiler, or the compiler class
+ (depending on the platform).
+
+ The linker will be instructed to link against libraries in the order they were
+ supplied to :meth:`add_library` and/or :meth:`set_libraries`. It is perfectly
+ valid to duplicate library names; the linker will be instructed to link against
+ libraries as many times as they are mentioned.
+
+
+ .. method:: CCompiler.set_libraries(libnames)
+
+ Set the list of libraries to be included in all links driven by this compiler
+ object to *libnames* (a list of strings). This does not affect any standard
+ system libraries that the linker may include by default.
+
+
+ .. method:: CCompiler.add_library_dir(dir)
+
+ Add *dir* to the list of directories that will be searched for libraries
+ specified to :meth:`add_library` and :meth:`set_libraries`. The linker will be
+ instructed to search for libraries in the order they are supplied to
+ :meth:`add_library_dir` and/or :meth:`set_library_dirs`.
+
+
+ .. method:: CCompiler.set_library_dirs(dirs)
+
+ Set the list of library search directories to *dirs* (a list of strings). This
+ does not affect any standard library search path that the linker may search by
+ default.
+
+
+ .. method:: CCompiler.add_runtime_library_dir(dir)
+
+ Add *dir* to the list of directories that will be searched for shared libraries
+ at runtime.
+
+
+ .. method:: CCompiler.set_runtime_library_dirs(dirs)
+
+ Set the list of directories to search for shared libraries at runtime to *dirs*
+ (a list of strings). This does not affect any standard search path that the
+ runtime linker may search by default.
+
+
+ .. method:: CCompiler.define_macro(name[, value=None])
+
+ Define a preprocessor macro for all compilations driven by this compiler object.
+ The optional parameter *value* should be a string; if it is not supplied, then
+ the macro will be defined without an explicit value and the exact outcome
+ depends on the compiler used (XXX true? does ANSI say anything about this?)
+
+
+ .. method:: CCompiler.undefine_macro(name)
+
+ Undefine a preprocessor macro for all compilations driven by this compiler
+ object. If the same macro is defined by :meth:`define_macro` and
+ undefined by :meth:`undefine_macro` the last call takes precedence
+ (including multiple redefinitions or undefinitions). If the macro is
+ redefined/undefined on a per-compilation basis (ie. in the call to
+ :meth:`compile`), then that takes precedence.
+
+
+ .. method:: CCompiler.add_link_object(object)
+
+ Add *object* to the list of object files (or analogues, such as explicitly named
+ library files or the output of "resource compilers") to be included in every
+ link driven by this compiler object.
+
+
+ .. method:: CCompiler.set_link_objects(objects)
+
+ Set the list of object files (or analogues) to be included in every link to
+ *objects*. This does not affect any standard object files that the linker may
+ include by default (such as system libraries).
+
+ The following methods implement methods for autodetection of compiler options,
+ providing some functionality similar to GNU :program:`autoconf`.
+
+
+ .. method:: CCompiler.detect_language(sources)
+
+ Detect the language of a given file, or list of files. Uses the instance
+ attributes :attr:`language_map` (a dictionary), and :attr:`language_order` (a
+ list) to do the job.
+
+
+ .. method:: CCompiler.find_library_file(dirs, lib[, debug=0])
+
+ Search the specified list of directories for a static or shared library file
+ *lib* and return the full path to that file. If *debug* is true, look for a
+ debugging version (if that makes sense on the current platform). Return
+ ``None`` if *lib* wasn't found in any of the specified directories.
+
+
+ .. method:: CCompiler.has_function(funcname [, includes=None, include_dirs=None, libraries=None, library_dirs=None])
+
+ Return a boolean indicating whether *funcname* is supported on the current
+ platform. The optional arguments can be used to augment the compilation
+ environment by providing additional include files and paths and libraries and
+ paths.
+
+
+ .. method:: CCompiler.library_dir_option(dir)
+
+ Return the compiler option to add *dir* to the list of directories searched for
+ libraries.
+
+
+ .. method:: CCompiler.library_option(lib)
+
+ Return the compiler option to add *dir* to the list of libraries linked into the
+ shared library or executable.
+
+
+ .. method:: CCompiler.runtime_library_dir_option(dir)
+
+ Return the compiler option to add *dir* to the list of directories searched for
+ runtime libraries.
+
+
+ .. method:: CCompiler.set_executables(**args)
+
+ Define the executables (and options for them) that will be run to perform the
+ various stages of compilation. The exact set of executables that may be
+ specified here depends on the compiler class (via the 'executables' class
+ attribute), but most will have:
+
+ +--------------+------------------------------------------+
+ | attribute | description |
+ +==============+==========================================+
+ | *compiler* | the C/C++ compiler |
+ +--------------+------------------------------------------+
+ | *linker_so* | linker used to create shared objects and |
+ | | libraries |
+ +--------------+------------------------------------------+
+ | *linker_exe* | linker used to create binary executables |
+ +--------------+------------------------------------------+
+ | *archiver* | static library creator |
+ +--------------+------------------------------------------+
+
+ On platforms with a command-line (Unix, DOS/Windows), each of these is a string
+ that will be split into executable name and (optional) list of arguments.
+ (Splitting the string is done similarly to how Unix shells operate: words are
+ delimited by spaces, but quotes and backslashes can override this. See
+ :func:`distutils.util.split_quoted`.)
+
+ The following methods invoke stages in the build process.
+
+
+ .. method:: CCompiler.compile(sources[, output_dir=None, macros=None, include_dirs=None, debug=0, extra_preargs=None, extra_postargs=None, depends=None])
+
+ Compile one or more source files. Generates object files (e.g. transforms a
+ :file:`.c` file to a :file:`.o` file.)
+
+ *sources* must be a list of filenames, most likely C/C++ files, but in reality
+ anything that can be handled by a particular compiler and compiler class (eg.
+ :class:`MSVCCompiler` can handle resource files in *sources*). Return a list of
+ object filenames, one per source filename in *sources*. Depending on the
+ implementation, not all source files will necessarily be compiled, but all
+ corresponding object filenames will be returned.
+
+ If *output_dir* is given, object files will be put under it, while retaining
+ their original path component. That is, :file:`foo/bar.c` normally compiles to
+ :file:`foo/bar.o` (for a Unix implementation); if *output_dir* is *build*, then
+ it would compile to :file:`build/foo/bar.o`.
+
+ *macros*, if given, must be a list of macro definitions. A macro definition is
+ either a ``(name, value)`` 2-tuple or a ``(name,)`` 1-tuple. The former defines
+ a macro; if the value is ``None``, the macro is defined without an explicit
+ value. The 1-tuple case undefines a macro. Later
+ definitions/redefinitions/undefinitions take precedence.
+
+ *include_dirs*, if given, must be a list of strings, the directories to add to
+ the default include file search path for this compilation only.
+
+ *debug* is a boolean; if true, the compiler will be instructed to output debug
+ symbols in (or alongside) the object file(s).
+
+ *extra_preargs* and *extra_postargs* are implementation-dependent. On platforms
+ that have the notion of a command-line (e.g. Unix, DOS/Windows), they are most
+ likely lists of strings: extra command-line arguments to prepend/append to the
+ compiler command line. On other platforms, consult the implementation class
+ documentation. In any event, they are intended as an escape hatch for those
+ occasions when the abstract compiler framework doesn't cut the mustard.
+
+ *depends*, if given, is a list of filenames that all targets depend on. If a
+ source file is older than any file in depends, then the source file will be
+ recompiled. This supports dependency tracking, but only at a coarse
+ granularity.
+
+ Raises :exc:`CompileError` on failure.
+
+
+ .. method:: CCompiler.create_static_lib(objects, output_libname[, output_dir=None, debug=0, target_lang=None])
+
+ Link a bunch of stuff together to create a static library file. The "bunch of
+ stuff" consists of the list of object files supplied as *objects*, the extra
+ object files supplied to :meth:`add_link_object` and/or
+ :meth:`set_link_objects`, the libraries supplied to :meth:`add_library` and/or
+ :meth:`set_libraries`, and the libraries supplied as *libraries* (if any).
+
+ *output_libname* should be a library name, not a filename; the filename will be
+ inferred from the library name. *output_dir* is the directory where the library
+ file will be put. XXX defaults to what?
+
+ *debug* is a boolean; if true, debugging information will be included in the
+ library (note that on most platforms, it is the compile step where this matters:
+ the *debug* flag is included here just for consistency).
+
+ *target_lang* is the target language for which the given objects are being
+ compiled. This allows specific linkage time treatment of certain languages.
+
+ Raises :exc:`LibError` on failure.
+
+
+ .. method:: CCompiler.link(target_desc, objects, output_filename[, output_dir=None, libraries=None, library_dirs=None, runtime_library_dirs=None, export_symbols=None, debug=0, extra_preargs=None, extra_postargs=None, build_temp=None, target_lang=None])
+
+ Link a bunch of stuff together to create an executable or shared library file.
+
+ The "bunch of stuff" consists of the list of object files supplied as *objects*.
+ *output_filename* should be a filename. If *output_dir* is supplied,
+ *output_filename* is relative to it (i.e. *output_filename* can provide
+ directory components if needed).
+
+ *libraries* is a list of libraries to link against. These are library names,
+ not filenames, since they're translated into filenames in a platform-specific
+ way (eg. *foo* becomes :file:`libfoo.a` on Unix and :file:`foo.lib` on
+ DOS/Windows). However, they can include a directory component, which means the
+ linker will look in that specific directory rather than searching all the normal
+ locations.
+
+ *library_dirs*, if supplied, should be a list of directories to search for
+ libraries that were specified as bare library names (ie. no directory
+ component). These are on top of the system default and those supplied to
+ :meth:`add_library_dir` and/or :meth:`set_library_dirs`. *runtime_library_dirs*
+ is a list of directories that will be embedded into the shared library and used
+ to search for other shared libraries that \*it\* depends on at run-time. (This
+ may only be relevant on Unix.)
+
+ *export_symbols* is a list of symbols that the shared library will export.
+ (This appears to be relevant only on Windows.)
+
+ *debug* is as for :meth:`compile` and :meth:`create_static_lib`, with the
+ slight distinction that it actually matters on most platforms (as opposed to
+ :meth:`create_static_lib`, which includes a *debug* flag mostly for form's
+ sake).
+
+ *extra_preargs* and *extra_postargs* are as for :meth:`compile` (except of
+ course that they supply command-line arguments for the particular linker being
+ used).
+
+ *target_lang* is the target language for which the given objects are being
+ compiled. This allows specific linkage time treatment of certain languages.
+
+ Raises :exc:`LinkError` on failure.
+
+
+ .. method:: CCompiler.link_executable(objects, output_progname[, output_dir=None, libraries=None, library_dirs=None, runtime_library_dirs=None, debug=0, extra_preargs=None, extra_postargs=None, target_lang=None])
+
+ Link an executable. *output_progname* is the name of the file executable, while
+ *objects* are a list of object filenames to link in. Other arguments are as for
+ the :meth:`link` method.
+
+
+ .. method:: CCompiler.link_shared_lib(objects, output_libname[, output_dir=None, libraries=None, library_dirs=None, runtime_library_dirs=None, export_symbols=None, debug=0, extra_preargs=None, extra_postargs=None, build_temp=None, target_lang=None])
+
+ Link a shared library. *output_libname* is the name of the output library,
+ while *objects* is a list of object filenames to link in. Other arguments are
+ as for the :meth:`link` method.
+
+
+ .. method:: CCompiler.link_shared_object(objects, output_filename[, output_dir=None, libraries=None, library_dirs=None, runtime_library_dirs=None, export_symbols=None, debug=0, extra_preargs=None, extra_postargs=None, build_temp=None, target_lang=None])
+
+ Link a shared object. *output_filename* is the name of the shared object that
+ will be created, while *objects* is a list of object filenames to link in.
+ Other arguments are as for the :meth:`link` method.
+
+
+ .. method:: CCompiler.preprocess(source[, output_file=None, macros=None, include_dirs=None, extra_preargs=None, extra_postargs=None])
+
+ Preprocess a single C/C++ source file, named in *source*. Output will be written
+ to file named *output_file*, or *stdout* if *output_file* not supplied.
+ *macros* is a list of macro definitions as for :meth:`compile`, which will
+ augment the macros set with :meth:`define_macro` and :meth:`undefine_macro`.
+ *include_dirs* is a list of directory names that will be added to the default
+ list, in the same way as :meth:`add_include_dir`.
+
+ Raises :exc:`PreprocessError` on failure.
+
+ The following utility methods are defined by the :class:`CCompiler` class, for
+ use by the various concrete subclasses.
+
+
+ .. method:: CCompiler.executable_filename(basename[, strip_dir=0, output_dir=''])
+
+ Returns the filename of the executable for the given *basename*. Typically for
+ non-Windows platforms this is the same as the basename, while Windows will get
+ a :file:`.exe` added.
+
+
+ .. method:: CCompiler.library_filename(libname[, lib_type='static', strip_dir=0, output_dir=''])
+
+ Returns the filename for the given library name on the current platform. On Unix
+ a library with *lib_type* of ``'static'`` will typically be of the form
+ :file:`liblibname.a`, while a *lib_type* of ``'dynamic'`` will be of the form
+ :file:`liblibname.so`.
+
+
+ .. method:: CCompiler.object_filenames(source_filenames[, strip_dir=0, output_dir=''])
+
+ Returns the name of the object files for the given source files.
+ *source_filenames* should be a list of filenames.
+
+
+ .. method:: CCompiler.shared_object_filename(basename[, strip_dir=0, output_dir=''])
+
+ Returns the name of a shared object file for the given file name *basename*.
+
+
+ .. method:: CCompiler.execute(func, args[, msg=None, level=1])
+
+ Invokes :func:`distutils.util.execute` This method invokes a Python function
+ *func* with the given arguments *args*, after logging and taking into account
+ the *dry_run* flag. XXX see also.
+
+
+ .. method:: CCompiler.spawn(cmd)
+
+ Invokes :func:`distutils.util.spawn`. This invokes an external process to run
+ the given command. XXX see also.
+
+
+ .. method:: CCompiler.mkpath(name[, mode=511])
+
+ Invokes :func:`distutils.dir_util.mkpath`. This creates a directory and any
+ missing ancestor directories. XXX see also.
+
+
+ .. method:: CCompiler.move_file(src, dst)
+
+ Invokes :meth:`distutils.file_util.move_file`. Renames *src* to *dst*. XXX see
+ also.
+
+
+ .. method:: CCompiler.announce(msg[, level=1])
+
+ Write a message using :func:`distutils.log.debug`. XXX see also.
+
+
+ .. method:: CCompiler.warn(msg)
+
+ Write a warning message *msg* to standard error.
+
+
+ .. method:: CCompiler.debug_print(msg)
+
+ If the *debug* flag is set on this :class:`CCompiler` instance, print *msg* to
+ standard output, otherwise do nothing.
+
+.. % \subsection{Compiler-specific modules}
+.. %
+.. % The following modules implement concrete subclasses of the abstract
+.. % \class{CCompiler} class. They should not be instantiated directly, but should
+.. % be created using \function{distutils.ccompiler.new_compiler()} factory
+.. % function.
+
+
+:mod:`distutils.unixccompiler` --- Unix C Compiler
+==================================================
+
+.. module:: distutils.unixccompiler
+ :synopsis: UNIX C Compiler
+
+
+This module provides the :class:`UnixCCompiler` class, a subclass of
+:class:`CCompiler` that handles the typical Unix-style command-line C compiler:
+
+* macros defined with :option:`-Dname[=value]`
+
+* macros undefined with :option:`-Uname`
+
+* include search directories specified with :option:`-Idir`
+
+* libraries specified with :option:`-llib`
+
+* library search directories specified with :option:`-Ldir`
+
+* compile handled by :program:`cc` (or similar) executable with :option:`-c`
+ option: compiles :file:`.c` to :file:`.o`
+
+* link static library handled by :program:`ar` command (possibly with
+ :program:`ranlib`)
+
+* link shared library handled by :program:`cc` :option:`-shared`
+
+
+:mod:`distutils.msvccompiler` --- Microsoft Compiler
+====================================================
+
+.. module:: distutils.msvccompiler
+ :synopsis: Microsoft Compiler
+
+
+This module provides :class:`MSVCCompiler`, an implementation of the abstract
+:class:`CCompiler` class for Microsoft Visual Studio. Typically, extension
+modules need to be compiled with the same compiler that was used to compile
+Python. For Python 2.3 and earlier, the compiler was Visual Studio 6. For Python
+2.4 and 2.5, the compiler is Visual Studio .NET 2003. The AMD64 and Itanium
+binaries are created using the Platform SDK.
+
+:class:`MSVCCompiler` will normally choose the right compiler, linker etc. on
+its own. To override this choice, the environment variables *DISTUTILS_USE_SDK*
+and *MSSdk* must be both set. *MSSdk* indicates that the current environment has
+been setup by the SDK's ``SetEnv.Cmd`` script, or that the environment variables
+had been registered when the SDK was installed; *DISTUTILS_USE_SDK* indicates
+that the distutils user has made an explicit choice to override the compiler
+selection by :class:`MSVCCompiler`.
+
+
+:mod:`distutils.bcppcompiler` --- Borland Compiler
+==================================================
+
+.. module:: distutils.bcppcompiler
+
+
+This module provides :class:`BorlandCCompiler`, an subclass of the abstract
+:class:`CCompiler` class for the Borland C++ compiler.
+
+
+:mod:`distutils.cygwincompiler` --- Cygwin Compiler
+===================================================
+
+.. module:: distutils.cygwinccompiler
+
+
+This module provides the :class:`CygwinCCompiler` class, a subclass of
+:class:`UnixCCompiler` that handles the Cygwin port of the GNU C compiler to
+Windows. It also contains the Mingw32CCompiler class which handles the mingw32
+port of GCC (same as cygwin in no-cygwin mode).
+
+
+:mod:`distutils.emxccompiler` --- OS/2 EMX Compiler
+===================================================
+
+.. module:: distutils.emxccompiler
+ :synopsis: OS/2 EMX Compiler support
+
+
+This module provides the EMXCCompiler class, a subclass of
+:class:`UnixCCompiler` that handles the EMX port of the GNU C compiler to OS/2.
+
+
+:mod:`distutils.mwerkscompiler` --- Metrowerks CodeWarrior support
+==================================================================
+
+.. module:: distutils.mwerkscompiler
+ :synopsis: Metrowerks CodeWarrior support
+
+
+Contains :class:`MWerksCompiler`, an implementation of the abstract
+:class:`CCompiler` class for MetroWerks CodeWarrior on the pre-Mac OS X
+Macintosh. Needs work to support CW on Windows or Mac OS X.
+
+.. % \subsection{Utility modules}
+.. %
+.. % The following modules all provide general utility functions. They haven't
+.. % all been documented yet.
+
+
+:mod:`distutils.archive_util` --- Archiving utilities
+======================================================
+
+.. module:: distutils.archive_util
+ :synopsis: Utility functions for creating archive files (tarballs, zip files, ...)
+
+
+This module provides a few functions for creating archive files, such as
+tarballs or zipfiles.
+
+
+.. function:: make_archive(base_name, format[, root_dir=None, base_dir=None, verbose=0, dry_run=0])
+
+ Create an archive file (eg. ``zip`` or ``tar``). *base_name* is the name of
+ the file to create, minus any format-specific extension; *format* is the
+ archive format: one of ``zip``, ``tar``, ``ztar``, or ``gztar``. *root_dir* is
+ a directory that will be the root directory of the archive; ie. we typically
+ ``chdir`` into *root_dir* before creating the archive. *base_dir* is the
+ directory where we start archiving from; ie. *base_dir* will be the common
+ prefix of all files and directories in the archive. *root_dir* and *base_dir*
+ both default to the current directory. Returns the name of the archive file.
+
+ .. warning::
+
+ This should be changed to support bz2 files
+
+
+.. function:: make_tarball(base_name, base_dir[, compress='gzip', verbose=0, dry_run=0])
+
+ 'Create an (optional compressed) archive as a tar file from all files in and
+ under *base_dir*. *compress* must be ``'gzip'`` (the default), ``'compress'``,
+ ``'bzip2'``, or ``None``. Both :program:`tar` and the compression utility named
+ by *compress* must be on the default program search path, so this is probably
+ Unix-specific. The output tar file will be named :file:`base_dir.tar`,
+ possibly plus the appropriate compression extension (:file:`.gz`, :file:`.bz2`
+ or :file:`.Z`). Return the output filename.
+
+ .. warning::
+
+ This should be replaced with calls to the :mod:`tarfile` module.
+
+
+.. function:: make_zipfile(base_name, base_dir[, verbose=0, dry_run=0])
+
+ Create a zip file from all files in and under *base_dir*. The output zip file
+ will be named *base_dir* + :file:`.zip`. Uses either the :mod:`zipfile` Python
+ module (if available) or the InfoZIP :file:`zip` utility (if installed and
+ found on the default search path). If neither tool is available, raises
+ :exc:`DistutilsExecError`. Returns the name of the output zip file.
+
+
+:mod:`distutils.dep_util` --- Dependency checking
+=================================================
+
+.. module:: distutils.dep_util
+ :synopsis: Utility functions for simple dependency checking
+
+
+This module provides functions for performing simple, timestamp-based
+dependency of files and groups of files; also, functions based entirely on such
+timestamp dependency analysis.
+
+
+.. function:: newer(source, target)
+
+ Return true if *source* exists and is more recently modified than *target*, or
+ if *source* exists and *target* doesn't. Return false if both exist and *target*
+ is the same age or newer than *source*. Raise :exc:`DistutilsFileError` if
+ *source* does not exist.
+
+
+.. function:: newer_pairwise(sources, targets)
+
+ Walk two filename lists in parallel, testing if each source is newer than its
+ corresponding target. Return a pair of lists (*sources*, *targets*) where
+ source is newer than target, according to the semantics of :func:`newer`
+
+ .. % % equivalent to a listcomp...
+
+
+.. function:: newer_group(sources, target[, missing='error'])
+
+ Return true if *target* is out-of-date with respect to any file listed in
+ *sources* In other words, if *target* exists and is newer than every file in
+ *sources*, return false; otherwise return true. *missing* controls what we do
+ when a source file is missing; the default (``'error'``) is to blow up with an
+ :exc:`OSError` from inside :func:`os.stat`; if it is ``'ignore'``, we silently
+ drop any missing source files; if it is ``'newer'``, any missing source files
+ make us assume that *target* is out-of-date (this is handy in "dry-run" mode:
+ it'll make you pretend to carry out commands that wouldn't work because inputs
+ are missing, but that doesn't matter because you're not actually going to run
+ the commands).
+
+
+:mod:`distutils.dir_util` --- Directory tree operations
+=======================================================
+
+.. module:: distutils.dir_util
+ :synopsis: Utility functions for operating on directories and directory trees
+
+
+This module provides functions for operating on directories and trees of
+directories.
+
+
+.. function:: mkpath(name[, mode=0777, verbose=0, dry_run=0])
+
+ Create a directory and any missing ancestor directories. If the directory
+ already exists (or if *name* is the empty string, which means the current
+ directory, which of course exists), then do nothing. Raise
+ :exc:`DistutilsFileError` if unable to create some directory along the way (eg.
+ some sub-path exists, but is a file rather than a directory). If *verbose* is
+ true, print a one-line summary of each mkdir to stdout. Return the list of
+ directories actually created.
+
+
+.. function:: create_tree(base_dir, files[, mode=0777, verbose=0, dry_run=0])
+
+ Create all the empty directories under *base_dir* needed to put *files* there.
+ *base_dir* is just the a name of a directory which doesn't necessarily exist
+ yet; *files* is a list of filenames to be interpreted relative to *base_dir*.
+ *base_dir* + the directory portion of every file in *files* will be created if
+ it doesn't already exist. *mode*, *verbose* and *dry_run* flags are as for
+ :func:`mkpath`.
+
+
+.. function:: copy_tree(src, dst[, preserve_mode=1, preserve_times=1, preserve_symlinks=0, update=0, verbose=0, dry_run=0])
+
+ Copy an entire directory tree *src* to a new location *dst*. Both *src* and
+ *dst* must be directory names. If *src* is not a directory, raise
+ :exc:`DistutilsFileError`. If *dst* does not exist, it is created with
+ :func:`mkpath`. The end result of the copy is that every file in *src* is
+ copied to *dst*, and directories under *src* are recursively copied to *dst*.
+ Return the list of files that were copied or might have been copied, using their
+ output name. The return value is unaffected by *update* or *dry_run*: it is
+ simply the list of all files under *src*, with the names changed to be under
+ *dst*.
+
+ *preserve_mode* and *preserve_times* are the same as for :func:`copy_file` in
+ :mod:`distutils.file_util`; note that they only apply to regular files, not to
+ directories. If *preserve_symlinks* is true, symlinks will be copied as
+ symlinks (on platforms that support them!); otherwise (the default), the
+ destination of the symlink will be copied. *update* and *verbose* are the same
+ as for :func:`copy_file`.
+
+
+.. function:: remove_tree(directory[, verbose=0, dry_run=0])
+
+ Recursively remove *directory* and all files and directories underneath it. Any
+ errors are ignored (apart from being reported to ``sys.stdout`` if *verbose* is
+ true).
+
+**\*\*** Some of this could be replaced with the shutil module? **\*\***
+
+
+:mod:`distutils.file_util` --- Single file operations
+=====================================================
+
+.. module:: distutils.file_util
+ :synopsis: Utility functions for operating on single files
+
+
+This module contains some utility functions for operating on individual files.
+
+
+.. function:: copy_file(src, dst[, preserve_mode=1, preserve_times=1, update=0, link=None, verbose=0, dry_run=0])
+
+ Copy file *src* to *dst*. If *dst* is a directory, then *src* is copied there
+ with the same name; otherwise, it must be a filename. (If the file exists, it
+ will be ruthlessly clobbered.) If *preserve_mode* is true (the default), the
+ file's mode (type and permission bits, or whatever is analogous on the
+ current platform) is copied. If *preserve_times* is true (the default), the
+ last-modified and last-access times are copied as well. If *update* is true,
+ *src* will only be copied if *dst* does not exist, or if *dst* does exist but
+ is older than *src*.
+
+ *link* allows you to make hard links (using :func:`os.link`) or symbolic links
+ (using :func:`os.symlink`) instead of copying: set it to ``'hard'`` or
+ ``'sym'``; if it is ``None`` (the default), files are copied. Don't set *link*
+ on systems that don't support it: :func:`copy_file` doesn't check if hard or
+ symbolic linking is available. It uses :func:`_copy_file_contents` to copy file
+ contents.
+
+ Return a tuple ``(dest_name, copied)``: *dest_name* is the actual name of the
+ output file, and *copied* is true if the file was copied (or would have been
+ copied, if *dry_run* true).
+
+ .. % XXX if the destination file already exists, we clobber it if
+ .. % copying, but blow up if linking. Hmmm. And I don't know what
+ .. % macostools.copyfile() does. Should definitely be consistent, and
+ .. % should probably blow up if destination exists and we would be
+ .. % changing it (ie. it's not already a hard/soft link to src OR
+ .. % (not update) and (src newer than dst)).
+
+
+.. function:: move_file(src, dst[, verbose, dry_run])
+
+ Move file *src* to *dst*. If *dst* is a directory, the file will be moved into
+ it with the same name; otherwise, *src* is just renamed to *dst*. Returns the
+ new full name of the file.
+
+ .. warning::
+
+ Handles cross-device moves on Unix using :func:`copy_file`. What about other
+ systems???
+
+
+.. function:: write_file(filename, contents)
+
+ Create a file called *filename* and write *contents* (a sequence of strings
+ without line terminators) to it.
+
+
+:mod:`distutils.util` --- Miscellaneous other utility functions
+===============================================================
+
+.. module:: distutils.util
+ :synopsis: Miscellaneous other utility functions
+
+
+This module contains other assorted bits and pieces that don't fit into any
+other utility module.
+
+
+.. function:: get_platform()
+
+ Return a string that identifies the current platform. This is used mainly to
+ distinguish platform-specific build directories and platform-specific built
+ distributions. Typically includes the OS name and version and the architecture
+ (as supplied by 'os.uname()'), although the exact information included depends
+ on the OS; eg. for IRIX the architecture isn't particularly important (IRIX only
+ runs on SGI hardware), but for Linux the kernel version isn't particularly
+ important.
+
+ Examples of returned values:
+
+ * ``linux-i586``
+ * ``linux-alpha``
+ * ``solaris-2.6-sun4u``
+ * ``irix-5.3``
+ * ``irix64-6.2``
+
+ For non-POSIX platforms, currently just returns ``sys.platform``.
+
+ .. % XXX isn't this also provided by some other non-distutils module?
+
+
+.. function:: convert_path(pathname)
+
+ Return 'pathname' as a name that will work on the native filesystem, i.e. split
+ it on '/' and put it back together again using the current directory separator.
+ Needed because filenames in the setup script are always supplied in Unix style,
+ and have to be converted to the local convention before we can actually use them
+ in the filesystem. Raises :exc:`ValueError` on non-Unix-ish systems if
+ *pathname* either starts or ends with a slash.
+
+
+.. function:: change_root(new_root, pathname)
+
+ Return *pathname* with *new_root* prepended. If *pathname* is relative, this is
+ equivalent to ``os.path.join(new_root,pathname)`` Otherwise, it requires making
+ *pathname* relative and then joining the two, which is tricky on DOS/Windows.
+
+
+.. function:: check_environ()
+
+ Ensure that 'os.environ' has all the environment variables we guarantee that
+ users can use in config files, command-line options, etc. Currently this
+ includes:
+
+ * :envvar:`HOME` - user's home directory (Unix only)
+ * :envvar:`PLAT` - description of the current platform, including hardware and
+ OS (see :func:`get_platform`)
+
+
+.. function:: subst_vars(s, local_vars)
+
+ Perform shell/Perl-style variable substitution on *s*. Every occurrence of
+ ``$`` followed by a name is considered a variable, and variable is substituted
+ by the value found in the *local_vars* dictionary, or in ``os.environ`` if it's
+ not in *local_vars*. *os.environ* is first checked/augmented to guarantee that
+ it contains certain values: see :func:`check_environ`. Raise :exc:`ValueError`
+ for any variables not found in either *local_vars* or ``os.environ``.
+
+ Note that this is not a fully-fledged string interpolation function. A valid
+ ``$variable`` can consist only of upper and lower case letters, numbers and an
+ underscore. No { } or ( ) style quoting is available.
+
+
+.. function:: grok_environment_error(exc[, prefix='error: '])
+
+ Generate a useful error message from an :exc:`EnvironmentError` (:exc:`IOError`
+ or :exc:`OSError`) exception object. Handles Python 1.5.1 and later styles,
+ and does what it can to deal with exception objects that don't have a filename
+ (which happens when the error is due to a two-file operation, such as
+ :func:`rename` or :func:`link`). Returns the error message as a string
+ prefixed with *prefix*.
+
+
+.. function:: split_quoted(s)
+
+ Split a string up according to Unix shell-like rules for quotes and backslashes.
+ In short: words are delimited by spaces, as long as those spaces are not escaped
+ by a backslash, or inside a quoted string. Single and double quotes are
+ equivalent, and the quote characters can be backslash-escaped. The backslash is
+ stripped from any two-character escape sequence, leaving only the escaped
+ character. The quote characters are stripped from any quoted string. Returns a
+ list of words.
+
+ .. % Should probably be moved into the standard library.
+
+
+.. function:: execute(func, args[, msg=None, verbose=0, dry_run=0])
+
+ Perform some action that affects the outside world (for instance, writing to the
+ filesystem). Such actions are special because they are disabled by the
+ *dry_run* flag. This method takes care of all that bureaucracy for you; all
+ you have to do is supply the function to call and an argument tuple for it (to
+ embody the "external action" being performed), and an optional message to print.
+
+
+.. function:: strtobool(val)
+
+ Convert a string representation of truth to true (1) or false (0).
+
+ True values are ``y``, ``yes``, ``t``, ``true``, ``on`` and ``1``; false values
+ are ``n``, ``no``, ``f``, ``false``, ``off`` and ``0``. Raises
+ :exc:`ValueError` if *val* is anything else.
+
+
+.. function:: byte_compile(py_files[, optimize=0, force=0, prefix=None, base_dir=None, verbose=1, dry_run=0, direct=None])
+
+ Byte-compile a collection of Python source files to either :file:`.pyc` or
+ :file:`.pyo` files in the same directory. *py_files* is a list of files to
+ compile; any files that don't end in :file:`.py` are silently skipped.
+ *optimize* must be one of the following:
+
+ * ``0`` - don't optimize (generate :file:`.pyc`)
+ * ``1`` - normal optimization (like ``python -O``)
+ * ``2`` - extra optimization (like ``python -OO``)
+
+ If *force* is true, all files are recompiled regardless of timestamps.
+
+ The source filename encoded in each bytecode file defaults to the filenames
+ listed in *py_files*; you can modify these with *prefix* and *basedir*.
+ *prefix* is a string that will be stripped off of each source filename, and
+ *base_dir* is a directory name that will be prepended (after *prefix* is
+ stripped). You can supply either or both (or neither) of *prefix* and
+ *base_dir*, as you wish.
+
+ If *dry_run* is true, doesn't actually do anything that would affect the
+ filesystem.
+
+ Byte-compilation is either done directly in this interpreter process with the
+ standard :mod:`py_compile` module, or indirectly by writing a temporary script
+ and executing it. Normally, you should let :func:`byte_compile` figure out to
+ use direct compilation or not (see the source for details). The *direct* flag
+ is used by the script generated in indirect mode; unless you know what you're
+ doing, leave it set to ``None``.
+
+
+.. function:: rfc822_escape(header)
+
+ Return a version of *header* escaped for inclusion in an :rfc:`822` header, by
+ ensuring there are 8 spaces space after each newline. Note that it does no other
+ modification of the string.
+
+ .. % this _can_ be replaced
+
+.. % \subsection{Distutils objects}
+
+
+:mod:`distutils.dist` --- The Distribution class
+================================================
+
+.. module:: distutils.dist
+ :synopsis: Provides the Distribution class, which represents the module distribution being
+ built/installed/distributed
+
+
+This module provides the :class:`Distribution` class, which represents the
+module distribution being built/installed/distributed.
+
+
+:mod:`distutils.extension` --- The Extension class
+==================================================
+
+.. module:: distutils.extension
+ :synopsis: Provides the Extension class, used to describe C/C++ extension modules in setup
+ scripts
+
+
+This module provides the :class:`Extension` class, used to describe C/C++
+extension modules in setup scripts.
+
+.. % \subsection{Ungrouped modules}
+.. % The following haven't been moved into a more appropriate section yet.
+
+
+:mod:`distutils.debug` --- Distutils debug mode
+===============================================
+
+.. module:: distutils.debug
+ :synopsis: Provides the debug flag for distutils
+
+
+This module provides the DEBUG flag.
+
+
+:mod:`distutils.errors` --- Distutils exceptions
+================================================
+
+.. module:: distutils.errors
+ :synopsis: Provides standard distutils exceptions
+
+
+Provides exceptions used by the Distutils modules. Note that Distutils modules
+may raise standard exceptions; in particular, SystemExit is usually raised for
+errors that are obviously the end-user's fault (eg. bad command-line arguments).
+
+This module is safe to use in ``from ... import *`` mode; it only exports
+symbols whose names start with ``Distutils`` and end with ``Error``.
+
+
+:mod:`distutils.fancy_getopt` --- Wrapper around the standard getopt module
+===========================================================================
+
+.. module:: distutils.fancy_getopt
+ :synopsis: Additional getopt functionality
+
+
+This module provides a wrapper around the standard :mod:`getopt` module that
+provides the following additional features:
+
+* short and long options are tied together
+
+* options have help strings, so :func:`fancy_getopt` could potentially create a
+ complete usage summary
+
+* options set attributes of a passed-in object
+
+* boolean options can have "negative aliases" --- eg. if :option:`--quiet` is
+ the "negative alias" of :option:`--verbose`, then :option:`--quiet` on the
+ command line sets *verbose* to false.
+
+**\*\*** Should be replaced with :mod:`optik` (which is also now known as
+:mod:`optparse` in Python 2.3 and later). **\*\***
+
+
+.. function:: fancy_getopt(options, negative_opt, object, args)
+
+ Wrapper function. *options* is a list of ``(long_option, short_option,
+ help_string)`` 3-tuples as described in the constructor for
+ :class:`FancyGetopt`. *negative_opt* should be a dictionary mapping option names
+ to option names, both the key and value should be in the *options* list.
+ *object* is an object which will be used to store values (see the :meth:`getopt`
+ method of the :class:`FancyGetopt` class). *args* is the argument list. Will use
+ ``sys.argv[1:]`` if you pass ``None`` as *args*.
+
+
+.. function:: wrap_text(text, width)
+
+ Wraps *text* to less than *width* wide.
+
+ .. warning::
+
+ Should be replaced with :mod:`textwrap` (which is available in Python 2.3 and
+ later).
+
+
+.. class:: FancyGetopt([option_table=None])
+
+ The option_table is a list of 3-tuples: ``(long_option, short_option,
+ help_string)``
+
+ If an option takes an argument, its *long_option* should have ``'='`` appended;
+ *short_option* should just be a single character, no ``':'`` in any case.
+ *short_option* should be ``None`` if a *long_option* doesn't have a
+ corresponding *short_option*. All option tuples must have long options.
+
+The :class:`FancyGetopt` class provides the following methods:
+
+
+.. method:: FancyGetopt.getopt([args=None, object=None])
+
+ Parse command-line options in args. Store as attributes on *object*.
+
+ If *args* is ``None`` or not supplied, uses ``sys.argv[1:]``. If *object* is
+ ``None`` or not supplied, creates a new :class:`OptionDummy` instance, stores
+ option values there, and returns a tuple ``(args, object)``. If *object* is
+ supplied, it is modified in place and :func:`getopt` just returns *args*; in
+ both cases, the returned *args* is a modified copy of the passed-in *args* list,
+ which is left untouched.
+
+ .. % and args returned are?
+
+
+.. method:: FancyGetopt.get_option_order()
+
+ Returns the list of ``(option, value)`` tuples processed by the previous run of
+ :meth:`getopt` Raises :exc:`RuntimeError` if :meth:`getopt` hasn't been called
+ yet.
+
+
+.. method:: FancyGetopt.generate_help([header=None])
+
+ Generate help text (a list of strings, one per suggested line of output) from
+ the option table for this :class:`FancyGetopt` object.
+
+ If supplied, prints the supplied *header* at the top of the help.
+
+
+:mod:`distutils.filelist` --- The FileList class
+================================================
+
+.. module:: distutils.filelist
+ :synopsis: The FileList class, used for poking about the file system and building lists of
+ files.
+
+
+This module provides the :class:`FileList` class, used for poking about the
+filesystem and building lists of files.
+
+
+:mod:`distutils.log` --- Simple PEP 282-style logging
+=====================================================
+
+.. module:: distutils.log
+ :synopsis: A simple logging mechanism, 282-style
+
+
+.. warning::
+
+ Should be replaced with standard :mod:`logging` module.
+
+.. % \subsubsection{\module{} --- }
+.. % \declaremodule{standard}{distutils.magic}
+.. % \modulesynopsis{ }
+
+
+:mod:`distutils.spawn` --- Spawn a sub-process
+==============================================
+
+.. module:: distutils.spawn
+ :synopsis: Provides the spawn() function
+
+
+This module provides the :func:`spawn` function, a front-end to various
+platform-specific functions for launching another program in a sub-process.
+Also provides :func:`find_executable` to search the path for a given executable
+name.
+
+
+:mod:`distutils.sysconfig` --- System configuration information
+===============================================================
+
+.. module:: distutils.sysconfig
+ :synopsis: Low-level access to configuration information of the Python interpreter.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. moduleauthor:: Greg Ward <gward@python.net>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`distutils.sysconfig` module provides access to Python's low-level
+configuration information. The specific configuration variables available
+depend heavily on the platform and configuration. The specific variables depend
+on the build process for the specific version of Python being run; the variables
+are those found in the :file:`Makefile` and configuration header that are
+installed with Python on Unix systems. The configuration header is called
+:file:`pyconfig.h` for Python versions starting with 2.2, and :file:`config.h`
+for earlier versions of Python.
+
+Some additional functions are provided which perform some useful manipulations
+for other parts of the :mod:`distutils` package.
+
+
+.. data:: PREFIX
+
+ The result of ``os.path.normpath(sys.prefix)``.
+
+
+.. data:: EXEC_PREFIX
+
+ The result of ``os.path.normpath(sys.exec_prefix)``.
+
+
+.. function:: get_config_var(name)
+
+ Return the value of a single variable. This is equivalent to
+ ``get_config_vars().get(name)``.
+
+
+.. function:: get_config_vars(...)
+
+ Return a set of variable definitions. If there are no arguments, this returns a
+ dictionary mapping names of configuration variables to values. If arguments are
+ provided, they should be strings, and the return value will be a sequence giving
+ the associated values. If a given name does not have a corresponding value,
+ ``None`` will be included for that variable.
+
+
+.. function:: get_config_h_filename()
+
+ Return the full path name of the configuration header. For Unix, this will be
+ the header generated by the :program:`configure` script; for other platforms the
+ header will have been supplied directly by the Python source distribution. The
+ file is a platform-specific text file.
+
+
+.. function:: get_makefile_filename()
+
+ Return the full path name of the :file:`Makefile` used to build Python. For
+ Unix, this will be a file generated by the :program:`configure` script; the
+ meaning for other platforms will vary. The file is a platform-specific text
+ file, if it exists. This function is only useful on POSIX platforms.
+
+
+.. function:: get_python_inc([plat_specific[, prefix]])
+
+ Return the directory for either the general or platform-dependent C include
+ files. If *plat_specific* is true, the platform-dependent include directory is
+ returned; if false or omitted, the platform-independent directory is returned.
+ If *prefix* is given, it is used as either the prefix instead of
+ :const:`PREFIX`, or as the exec-prefix instead of :const:`EXEC_PREFIX` if
+ *plat_specific* is true.
+
+
+.. function:: get_python_lib([plat_specific[, standard_lib[, prefix]]])
+
+ Return the directory for either the general or platform-dependent library
+ installation. If *plat_specific* is true, the platform-dependent include
+ directory is returned; if false or omitted, the platform-independent directory
+ is returned. If *prefix* is given, it is used as either the prefix instead of
+ :const:`PREFIX`, or as the exec-prefix instead of :const:`EXEC_PREFIX` if
+ *plat_specific* is true. If *standard_lib* is true, the directory for the
+ standard library is returned rather than the directory for the installation of
+ third-party extensions.
+
+The following function is only intended for use within the :mod:`distutils`
+package.
+
+
+.. function:: customize_compiler(compiler)
+
+ Do any platform-specific customization of a
+ :class:`distutils.ccompiler.CCompiler` instance.
+
+ This function is only needed on Unix at this time, but should be called
+ consistently to support forward-compatibility. It inserts the information that
+ varies across Unix flavors and is stored in Python's :file:`Makefile`. This
+ information includes the selected compiler, compiler and linker options, and the
+ extension used by the linker for shared objects.
+
+This function is even more special-purpose, and should only be used from
+Python's own build procedures.
+
+
+.. function:: set_python_build()
+
+ Inform the :mod:`distutils.sysconfig` module that it is being used as part of
+ the build process for Python. This changes a lot of relative locations for
+ files, allowing them to be located in the build area rather than in an installed
+ Python.
+
+
+:mod:`distutils.text_file` --- The TextFile class
+=================================================
+
+.. module:: distutils.text_file
+ :synopsis: provides the TextFile class, a simple interface to text files
+
+
+This module provides the :class:`TextFile` class, which gives an interface to
+text files that (optionally) takes care of stripping comments, ignoring blank
+lines, and joining lines with backslashes.
+
+
+.. class:: TextFile([filename=None, file=None, **options])
+
+ This class provides a file-like object that takes care of all the things you
+ commonly want to do when processing a text file that has some line-by-line
+ syntax: strip comments (as long as ``#`` is your comment character), skip blank
+ lines, join adjacent lines by escaping the newline (ie. backslash at end of
+ line), strip leading and/or trailing whitespace. All of these are optional and
+ independently controllable.
+
+ The class provides a :meth:`warn` method so you can generate warning messages
+ that report physical line number, even if the logical line in question spans
+ multiple physical lines. Also provides :meth:`unreadline` for implementing
+ line-at-a-time lookahead.
+
+ :class:`TextFile` instances are create with either *filename*, *file*, or both.
+ :exc:`RuntimeError` is raised if both are ``None``. *filename* should be a
+ string, and *file* a file object (or something that provides :meth:`readline`
+ and :meth:`close` methods). It is recommended that you supply at least
+ *filename*, so that :class:`TextFile` can include it in warning messages. If
+ *file* is not supplied, :class:`TextFile` creates its own using the
+ :func:`open` built-in function.
+
+ The options are all boolean, and affect the values returned by :meth:`readline`
+
+ +------------------+--------------------------------+---------+
+ | option name | description | default |
+ +==================+================================+=========+
+ | *strip_comments* | strip from ``'#'`` to end-of- | true |
+ | | line, as well as any | |
+ | | whitespace leading up to the | |
+ | | ``'#'``\ ---unless it is | |
+ | | escaped by a backslash | |
+ +------------------+--------------------------------+---------+
+ | *lstrip_ws* | strip leading whitespace from | false |
+ | | each line before returning it | |
+ +------------------+--------------------------------+---------+
+ | *rstrip_ws* | strip trailing whitespace | true |
+ | | (including line terminator!) | |
+ | | from each line before | |
+ | | returning it. | |
+ +------------------+--------------------------------+---------+
+ | *skip_blanks* | skip lines that are empty | true |
+ | | \*after\* stripping comments | |
+ | | and whitespace. (If both | |
+ | | lstrip_ws and rstrip_ws are | |
+ | | false, then some lines may | |
+ | | consist of solely whitespace: | |
+ | | these will \*not\* be skipped, | |
+ | | even if *skip_blanks* is | |
+ | | true.) | |
+ +------------------+--------------------------------+---------+
+ | *join_lines* | if a backslash is the last | false |
+ | | non-newline character on a | |
+ | | line after stripping comments | |
+ | | and whitespace, join the | |
+ | | following line to it to form | |
+ | | one logical line; if N | |
+ | | consecutive lines end with a | |
+ | | backslash, then N+1 physical | |
+ | | lines will be joined to form | |
+ | | one logical line. | |
+ +------------------+--------------------------------+---------+
+ | *collapse_join* | strip leading whitespace from | false |
+ | | lines that are joined to their | |
+ | | predecessor; only matters if | |
+ | | ``(join_lines and not | |
+ | | lstrip_ws)`` | |
+ +------------------+--------------------------------+---------+
+
+ Note that since *rstrip_ws* can strip the trailing newline, the semantics of
+ :meth:`readline` must differ from those of the builtin file object's
+ :meth:`readline` method! In particular, :meth:`readline` returns ``None`` for
+ end-of-file: an empty string might just be a blank line (or an all-whitespace
+ line), if *rstrip_ws* is true but *skip_blanks* is not.
+
+
+ .. method:: TextFile.open(filename)
+
+ Open a new file *filename*. This overrides any *file* or *filename* constructor
+ arguments.
+
+
+ .. method:: TextFile.close()
+
+ Close the current file and forget everything we know about it (including the
+ filename and the current line number).
+
+
+ .. method:: TextFile.warn(msg[,line=None])
+
+ Print (to stderr) a warning message tied to the current logical line in the
+ current file. If the current logical line in the file spans multiple physical
+ lines, the warning refers to the whole range, such as ``"lines 3-5"``. If
+ *line* is supplied, it overrides the current line number; it may be a list or
+ tuple to indicate a range of physical lines, or an integer for a single
+ physical line.
+
+
+ .. method:: TextFile.readline()
+
+ Read and return a single logical line from the current file (or from an internal
+ buffer if lines have previously been "unread" with :meth:`unreadline`). If the
+ *join_lines* option is true, this may involve reading multiple physical lines
+ concatenated into a single string. Updates the current line number, so calling
+ :meth:`warn` after :meth:`readline` emits a warning about the physical line(s)
+ just read. Returns ``None`` on end-of-file, since the empty string can occur
+ if *rstrip_ws* is true but *strip_blanks* is not.
+
+
+ .. method:: TextFile.readlines()
+
+ Read and return the list of all logical lines remaining in the current file.
+ This updates the current line number to the last line of the file.
+
+
+ .. method:: TextFile.unreadline(line)
+
+ Push *line* (a string) onto an internal buffer that will be checked by future
+ :meth:`readline` calls. Handy for implementing a parser with line-at-a-time
+ lookahead. Note that lines that are "unread" with :meth:`unreadline` are not
+ subsequently re-cleansed (whitespace stripped, or whatever) when read with
+ :meth:`readline`. If multiple calls are made to :meth:`unreadline` before a call
+ to :meth:`readline`, the lines will be returned most in most recent first order.
+
+
+:mod:`distutils.version` --- Version number classes
+===================================================
+
+.. module:: distutils.version
+ :synopsis: implements classes that represent module version numbers.
+
+
+.. % todo
+.. % \section{Distutils Commands}
+.. %
+.. % This part of Distutils implements the various Distutils commands, such
+.. % as \code{build}, \code{install} \&c. Each command is implemented as a
+.. % separate module, with the command name as the name of the module.
+
+
+:mod:`distutils.cmd` --- Abstract base class for Distutils commands
+===================================================================
+
+.. module:: distutils.cmd
+ :synopsis: This module provides the abstract base class Command. This class is subclassed
+ by the modules in the distutils.command subpackage.
+
+
+This module supplies the abstract base class :class:`Command`.
+
+
+.. class:: Command(dist)
+
+ Abstract base class for defining command classes, the "worker bees" of the
+ Distutils. A useful analogy for command classes is to think of them as
+ subroutines with local variables called *options*. The options are declared in
+ :meth:`initialize_options` and defined (given their final values) in
+ :meth:`finalize_options`, both of which must be defined by every command class.
+ The distinction between the two is necessary because option values might come
+ from the outside world (command line, config file, ...), and any options
+ dependent on other options must be computed after these outside influences have
+ been processed --- hence :meth:`finalize_options`. The body of the subroutine,
+ where it does all its work based on the values of its options, is the
+ :meth:`run` method, which must also be implemented by every command class.
+
+ The class constructor takes a single argument *dist*, a :class:`Distribution`
+ instance.
+
+
+:mod:`distutils.command` --- Individual Distutils commands
+==========================================================
+
+.. module:: distutils.command
+ :synopsis: This subpackage contains one module for each standard Distutils command.
+
+
+.. % \subsubsection{Individual Distutils commands}
+.. % todo
+
+
+:mod:`distutils.command.bdist` --- Build a binary installer
+===========================================================
+
+.. module:: distutils.command.bdist
+ :synopsis: Build a binary installer for a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.bdist_packager` --- Abstract base class for packagers
+=============================================================================
+
+.. module:: distutils.command.bdist_packager
+ :synopsis: Abstract base class for packagers
+
+
+.. % todo
+
+
+:mod:`distutils.command.bdist_dumb` --- Build a "dumb" installer
+================================================================
+
+.. module:: distutils.command.bdist_dumb
+ :synopsis: Build a "dumb" installer - a simple archive of files
+
+
+.. % todo
+
+
+:mod:`distutils.command.bdist_msi` --- Build a Microsoft Installer binary package
+=================================================================================
+
+.. module:: distutils.command.bdist_msi
+ :synopsis: Build a binary distribution as a Windows MSI file
+
+
+.. % todo
+
+
+:mod:`distutils.command.bdist_rpm` --- Build a binary distribution as a Redhat RPM and SRPM
+===========================================================================================
+
+.. module:: distutils.command.bdist_rpm
+ :synopsis: Build a binary distribution as a Redhat RPM and SRPM
+
+
+.. % todo
+
+
+:mod:`distutils.command.bdist_wininst` --- Build a Windows installer
+====================================================================
+
+.. module:: distutils.command.bdist_wininst
+ :synopsis: Build a Windows installer
+
+
+.. % todo
+
+
+:mod:`distutils.command.sdist` --- Build a source distribution
+==============================================================
+
+.. module:: distutils.command.sdist
+ :synopsis: Build a source distribution
+
+
+.. % todo
+
+
+:mod:`distutils.command.build` --- Build all files of a package
+===============================================================
+
+.. module:: distutils.command.build
+ :synopsis: Build all files of a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.build_clib` --- Build any C libraries in a package
+==========================================================================
+
+.. module:: distutils.command.build_clib
+ :synopsis: Build any C libraries in a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.build_ext` --- Build any extensions in a package
+========================================================================
+
+.. module:: distutils.command.build_ext
+ :synopsis: Build any extensions in a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.build_py` --- Build the .py/.pyc files of a package
+===========================================================================
+
+.. module:: distutils.command.build_py
+ :synopsis: Build the .py/.pyc files of a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.build_scripts` --- Build the scripts of a package
+=========================================================================
+
+.. module:: distutils.command.build_scripts
+ :synopsis: Build the scripts of a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.clean` --- Clean a package build area
+=============================================================
+
+.. module:: distutils.command.clean
+ :synopsis: Clean a package build area
+
+
+.. % todo
+
+
+:mod:`distutils.command.config` --- Perform package configuration
+=================================================================
+
+.. module:: distutils.command.config
+ :synopsis: Perform package configuration
+
+
+.. % todo
+
+
+:mod:`distutils.command.install` --- Install a package
+======================================================
+
+.. module:: distutils.command.install
+ :synopsis: Install a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.install_data` --- Install data files from a package
+===========================================================================
+
+.. module:: distutils.command.install_data
+ :synopsis: Install data files from a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.install_headers` --- Install C/C++ header files from a package
+======================================================================================
+
+.. module:: distutils.command.install_headers
+ :synopsis: Install C/C++ header files from a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.install_lib` --- Install library files from a package
+=============================================================================
+
+.. module:: distutils.command.install_lib
+ :synopsis: Install library files from a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.install_scripts` --- Install script files from a package
+================================================================================
+
+.. module:: distutils.command.install_scripts
+ :synopsis: Install script files from a package
+
+
+.. % todo
+
+
+:mod:`distutils.command.register` --- Register a module with the Python Package Index
+=====================================================================================
+
+.. module:: distutils.command.register
+ :synopsis: Register a module with the Python Package Index
+
+
+The ``register`` command registers the package with the Python Package Index.
+This is described in more detail in :pep:`301`.
+
+.. % todo
+
+
+Creating a new Distutils command
+================================
+
+This section outlines the steps to create a new Distutils command.
+
+A new command lives in a module in the :mod:`distutils.command` package. There
+is a sample template in that directory called :file:`command_template`. Copy
+this file to a new module with the same name as the new command you're
+implementing. This module should implement a class with the same name as the
+module (and the command). So, for instance, to create the command
+``peel_banana`` (so that users can run ``setup.py peel_banana``), you'd copy
+:file:`command_template` to :file:`distutils/command/peel_banana.py`, then edit
+it so that it's implementing the class :class:`peel_banana`, a subclass of
+:class:`distutils.cmd.Command`.
+
+Subclasses of :class:`Command` must define the following methods.
+
+
+.. method:: Command.initialize_options()(S)
+
+ et default values for all the options that this command supports. Note that
+ these defaults may be overridden by other commands, by the setup script, by
+ config files, or by the command-line. Thus, this is not the place to code
+ dependencies between options; generally, :meth:`initialize_options`
+ implementations are just a bunch of ``self.foo = None`` assignments.
+
+
+.. method:: Command.finalize_options()
+
+ Set final values for all the options that this command supports. This is
+ always called as late as possible, ie. after any option assignments from the
+ command-line or from other commands have been done. Thus, this is the place
+ to to code option dependencies: if *foo* depends on *bar*, then it is safe to
+ set *foo* from *bar* as long as *foo* still has the same value it was
+ assigned in :meth:`initialize_options`.
+
+
+.. method:: Command.run()
+
+ A command's raison d'etre: carry out the action it exists to perform, controlled
+ by the options initialized in :meth:`initialize_options`, customized by other
+ commands, the setup script, the command-line, and config files, and finalized in
+ :meth:`finalize_options`. All terminal output and filesystem interaction should
+ be done by :meth:`run`.
+
+*sub_commands* formalizes the notion of a "family" of commands, eg. ``install``
+as the parent with sub-commands ``install_lib``, ``install_headers``, etc. The
+parent of a family of commands defines *sub_commands* as a class attribute; it's
+a list of 2-tuples ``(command_name, predicate)``, with *command_name* a string
+and *predicate* an unbound method, a string or None. *predicate* is a method of
+the parent command that determines whether the corresponding command is
+applicable in the current situation. (Eg. we ``install_headers`` is only
+applicable if we have any C header files to install.) If *predicate* is None,
+that command is always applicable.
+
+*sub_commands* is usually defined at the \*end\* of a class, because predicates
+can be unbound methods, so they must already have been defined. The canonical
+example is the :command:`install` command.
diff --git a/Doc/distutils/builtdist.rst b/Doc/distutils/builtdist.rst
new file mode 100644
index 0000000000..b40ddeb369
--- /dev/null
+++ b/Doc/distutils/builtdist.rst
@@ -0,0 +1,405 @@
+.. _built-dist:
+
+****************************
+Creating Built Distributions
+****************************
+
+A "built distribution" is what you're probably used to thinking of either as a
+"binary package" or an "installer" (depending on your background). It's not
+necessarily binary, though, because it might contain only Python source code
+and/or byte-code; and we don't call it a package, because that word is already
+spoken for in Python. (And "installer" is a term specific to the world of
+mainstream desktop systems.)
+
+A built distribution is how you make life as easy as possible for installers of
+your module distribution: for users of RPM-based Linux systems, it's a binary
+RPM; for Windows users, it's an executable installer; for Debian-based Linux
+users, it's a Debian package; and so forth. Obviously, no one person will be
+able to create built distributions for every platform under the sun, so the
+Distutils are designed to enable module developers to concentrate on their
+specialty---writing code and creating source distributions---while an
+intermediary species called *packagers* springs up to turn source distributions
+into built distributions for as many platforms as there are packagers.
+
+Of course, the module developer could be his own packager; or the packager could
+be a volunteer "out there" somewhere who has access to a platform which the
+original developer does not; or it could be software periodically grabbing new
+source distributions and turning them into built distributions for as many
+platforms as the software has access to. Regardless of who they are, a packager
+uses the setup script and the :command:`bdist` command family to generate built
+distributions.
+
+As a simple example, if I run the following command in the Distutils source
+tree::
+
+ python setup.py bdist
+
+then the Distutils builds my module distribution (the Distutils itself in this
+case), does a "fake" installation (also in the :file:`build` directory), and
+creates the default type of built distribution for my platform. The default
+format for built distributions is a "dumb" tar file on Unix, and a simple
+executable installer on Windows. (That tar file is considered "dumb" because it
+has to be unpacked in a specific location to work.)
+
+Thus, the above command on a Unix system creates
+:file:`Distutils-1.0.{plat}.tar.gz`; unpacking this tarball from the right place
+installs the Distutils just as though you had downloaded the source distribution
+and run ``python setup.py install``. (The "right place" is either the root of
+the filesystem or Python's :file:`{prefix}` directory, depending on the options
+given to the :command:`bdist_dumb` command; the default is to make dumb
+distributions relative to :file:`{prefix}`.)
+
+Obviously, for pure Python distributions, this isn't any simpler than just
+running ``python setup.py install``\ ---but for non-pure distributions, which
+include extensions that would need to be compiled, it can mean the difference
+between someone being able to use your extensions or not. And creating "smart"
+built distributions, such as an RPM package or an executable installer for
+Windows, is far more convenient for users even if your distribution doesn't
+include any extensions.
+
+The :command:`bdist` command has a :option:`--formats` option, similar to the
+:command:`sdist` command, which you can use to select the types of built
+distribution to generate: for example, ::
+
+ python setup.py bdist --format=zip
+
+would, when run on a Unix system, create :file:`Distutils-1.0.{plat}.zip`\
+---again, this archive would be unpacked from the root directory to install the
+Distutils.
+
+The available formats for built distributions are:
+
++-------------+------------------------------+---------+
+| Format | Description | Notes |
++=============+==============================+=========+
+| ``gztar`` | gzipped tar file | (1),(3) |
+| | (:file:`.tar.gz`) | |
++-------------+------------------------------+---------+
+| ``ztar`` | compressed tar file | \(3) |
+| | (:file:`.tar.Z`) | |
++-------------+------------------------------+---------+
+| ``tar`` | tar file (:file:`.tar`) | \(3) |
++-------------+------------------------------+---------+
+| ``zip`` | zip file (:file:`.zip`) | \(4) |
++-------------+------------------------------+---------+
+| ``rpm`` | RPM | \(5) |
++-------------+------------------------------+---------+
+| ``pkgtool`` | Solaris :program:`pkgtool` | |
++-------------+------------------------------+---------+
+| ``sdux`` | HP-UX :program:`swinstall` | |
++-------------+------------------------------+---------+
+| ``rpm`` | RPM | \(5) |
++-------------+------------------------------+---------+
+| ``wininst`` | self-extracting ZIP file for | (2),(4) |
+| | Windows | |
++-------------+------------------------------+---------+
+
+Notes:
+
+(1)
+ default on Unix
+
+(2)
+ default on Windows
+
+ **\*\*** to-do! **\*\***
+
+(3)
+ requires external utilities: :program:`tar` and possibly one of :program:`gzip`,
+ :program:`bzip2`, or :program:`compress`
+
+(4)
+ requires either external :program:`zip` utility or :mod:`zipfile` module (part
+ of the standard Python library since Python 1.6)
+
+(5)
+ requires external :program:`rpm` utility, version 3.0.4 or better (use ``rpm
+ --version`` to find out which version you have)
+
+You don't have to use the :command:`bdist` command with the :option:`--formats`
+option; you can also use the command that directly implements the format you're
+interested in. Some of these :command:`bdist` "sub-commands" actually generate
+several similar formats; for instance, the :command:`bdist_dumb` command
+generates all the "dumb" archive formats (``tar``, ``ztar``, ``gztar``, and
+``zip``), and :command:`bdist_rpm` generates both binary and source RPMs. The
+:command:`bdist` sub-commands, and the formats generated by each, are:
+
++--------------------------+-----------------------+
+| Command | Formats |
++==========================+=======================+
+| :command:`bdist_dumb` | tar, ztar, gztar, zip |
++--------------------------+-----------------------+
+| :command:`bdist_rpm` | rpm, srpm |
++--------------------------+-----------------------+
+| :command:`bdist_wininst` | wininst |
++--------------------------+-----------------------+
+
+The following sections give details on the individual :command:`bdist_\*`
+commands.
+
+
+.. _creating-dumb:
+
+Creating dumb built distributions
+=================================
+
+**\*\*** Need to document absolute vs. prefix-relative packages here, but first
+I have to implement it! **\*\***
+
+
+.. _creating-rpms:
+
+Creating RPM packages
+=====================
+
+The RPM format is used by many popular Linux distributions, including Red Hat,
+SuSE, and Mandrake. If one of these (or any of the other RPM-based Linux
+distributions) is your usual environment, creating RPM packages for other users
+of that same distribution is trivial. Depending on the complexity of your module
+distribution and differences between Linux distributions, you may also be able
+to create RPMs that work on different RPM-based distributions.
+
+The usual way to create an RPM of your module distribution is to run the
+:command:`bdist_rpm` command::
+
+ python setup.py bdist_rpm
+
+or the :command:`bdist` command with the :option:`--format` option::
+
+ python setup.py bdist --formats=rpm
+
+The former allows you to specify RPM-specific options; the latter allows you to
+easily specify multiple formats in one run. If you need to do both, you can
+explicitly specify multiple :command:`bdist_\*` commands and their options::
+
+ python setup.py bdist_rpm --packager="John Doe <jdoe@example.org>" \
+ bdist_wininst --target_version="2.0"
+
+Creating RPM packages is driven by a :file:`.spec` file, much as using the
+Distutils is driven by the setup script. To make your life easier, the
+:command:`bdist_rpm` command normally creates a :file:`.spec` file based on the
+information you supply in the setup script, on the command line, and in any
+Distutils configuration files. Various options and sections in the
+:file:`.spec` file are derived from options in the setup script as follows:
+
++------------------------------------------+----------------------------------------------+
+| RPM :file:`.spec` file option or section | Distutils setup script option |
++==========================================+==============================================+
+| Name | :option:`name` |
++------------------------------------------+----------------------------------------------+
+| Summary (in preamble) | :option:`description` |
++------------------------------------------+----------------------------------------------+
+| Version | :option:`version` |
++------------------------------------------+----------------------------------------------+
+| Vendor | :option:`author` and :option:`author_email`, |
+| | or --- & :option:`maintainer` and |
+| | :option:`maintainer_email` |
++------------------------------------------+----------------------------------------------+
+| Copyright | :option:`licence` |
++------------------------------------------+----------------------------------------------+
+| Url | :option:`url` |
++------------------------------------------+----------------------------------------------+
+| %description (section) | :option:`long_description` |
++------------------------------------------+----------------------------------------------+
+
+Additionally, there are many options in :file:`.spec` files that don't have
+corresponding options in the setup script. Most of these are handled through
+options to the :command:`bdist_rpm` command as follows:
+
++-------------------------------+-----------------------------+-------------------------+
+| RPM :file:`.spec` file option | :command:`bdist_rpm` option | default value |
+| or section | | |
++===============================+=============================+=========================+
+| Release | :option:`release` | "1" |
++-------------------------------+-----------------------------+-------------------------+
+| Group | :option:`group` | "Development/Libraries" |
++-------------------------------+-----------------------------+-------------------------+
+| Vendor | :option:`vendor` | (see above) |
++-------------------------------+-----------------------------+-------------------------+
+| Packager | :option:`packager` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| Provides | :option:`provides` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| Requires | :option:`requires` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| Conflicts | :option:`conflicts` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| Obsoletes | :option:`obsoletes` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| Distribution | :option:`distribution_name` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| BuildRequires | :option:`build_requires` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+| Icon | :option:`icon` | (none) |
++-------------------------------+-----------------------------+-------------------------+
+
+Obviously, supplying even a few of these options on the command-line would be
+tedious and error-prone, so it's usually best to put them in the setup
+configuration file, :file:`setup.cfg`\ ---see section :ref:`setup-config`. If
+you distribute or package many Python module distributions, you might want to
+put options that apply to all of them in your personal Distutils configuration
+file (:file:`~/.pydistutils.cfg`).
+
+There are three steps to building a binary RPM package, all of which are
+handled automatically by the Distutils:
+
+#. create a :file:`.spec` file, which describes the package (analogous to the
+ Distutils setup script; in fact, much of the information in the setup script
+ winds up in the :file:`.spec` file)
+
+#. create the source RPM
+
+#. create the "binary" RPM (which may or may not contain binary code, depending
+ on whether your module distribution contains Python extensions)
+
+Normally, RPM bundles the last two steps together; when you use the Distutils,
+all three steps are typically bundled together.
+
+If you wish, you can separate these three steps. You can use the
+:option:`--spec-only` option to make :command:`bdist_rpm` just create the
+:file:`.spec` file and exit; in this case, the :file:`.spec` file will be
+written to the "distribution directory"---normally :file:`dist/`, but
+customizable with the :option:`--dist-dir` option. (Normally, the :file:`.spec`
+file winds up deep in the "build tree," in a temporary directory created by
+:command:`bdist_rpm`.)
+
+.. % \XXX{this isn't implemented yet---is it needed?!}
+.. % You can also specify a custom \file{.spec} file with the
+.. % \longprogramopt{spec-file} option; used in conjunction with
+.. % \longprogramopt{spec-only}, this gives you an opportunity to customize
+.. % the \file{.spec} file manually:
+.. %
+.. % \ begin{verbatim}
+.. % > python setup.py bdist_rpm --spec-only
+.. % # ...edit dist/FooBar-1.0.spec
+.. % > python setup.py bdist_rpm --spec-file=dist/FooBar-1.0.spec
+.. % \ end{verbatim}
+.. %
+.. % (Although a better way to do this is probably to override the standard
+.. % \command{bdist\_rpm} command with one that writes whatever else you want
+.. % to the \file{.spec} file.)
+
+
+.. _creating-wininst:
+
+Creating Windows Installers
+===========================
+
+Executable installers are the natural format for binary distributions on
+Windows. They display a nice graphical user interface, display some information
+about the module distribution to be installed taken from the metadata in the
+setup script, let the user select a few options, and start or cancel the
+installation.
+
+Since the metadata is taken from the setup script, creating Windows installers
+is usually as easy as running::
+
+ python setup.py bdist_wininst
+
+or the :command:`bdist` command with the :option:`--formats` option::
+
+ python setup.py bdist --formats=wininst
+
+If you have a pure module distribution (only containing pure Python modules and
+packages), the resulting installer will be version independent and have a name
+like :file:`foo-1.0.win32.exe`. These installers can even be created on Unix or
+Mac OS platforms.
+
+If you have a non-pure distribution, the extensions can only be created on a
+Windows platform, and will be Python version dependent. The installer filename
+will reflect this and now has the form :file:`foo-1.0.win32-py2.0.exe`. You
+have to create a separate installer for every Python version you want to
+support.
+
+The installer will try to compile pure modules into bytecode after installation
+on the target system in normal and optimizing mode. If you don't want this to
+happen for some reason, you can run the :command:`bdist_wininst` command with
+the :option:`--no-target-compile` and/or the :option:`--no-target-optimize`
+option.
+
+By default the installer will display the cool "Python Powered" logo when it is
+run, but you can also supply your own bitmap which must be a Windows
+:file:`.bmp` file with the :option:`--bitmap` option.
+
+The installer will also display a large title on the desktop background window
+when it is run, which is constructed from the name of your distribution and the
+version number. This can be changed to another text by using the
+:option:`--title` option.
+
+The installer file will be written to the "distribution directory" --- normally
+:file:`dist/`, but customizable with the :option:`--dist-dir` option.
+
+
+.. _postinstallation-script:
+
+The Postinstallation script
+---------------------------
+
+Starting with Python 2.3, a postinstallation script can be specified which the
+:option:`--install-script` option. The basename of the script must be
+specified, and the script filename must also be listed in the scripts argument
+to the setup function.
+
+This script will be run at installation time on the target system after all the
+files have been copied, with ``argv[1]`` set to :option:`-install`, and again at
+uninstallation time before the files are removed with ``argv[1]`` set to
+:option:`-remove`.
+
+The installation script runs embedded in the windows installer, every output
+(``sys.stdout``, ``sys.stderr``) is redirected into a buffer and will be
+displayed in the GUI after the script has finished.
+
+Some functions especially useful in this context are available as additional
+built-in functions in the installation script.
+
+
+.. function:: directory_created(path)
+ file_created(path)
+
+ These functions should be called when a directory or file is created by the
+ postinstall script at installation time. It will register *path* with the
+ uninstaller, so that it will be removed when the distribution is uninstalled.
+ To be safe, directories are only removed if they are empty.
+
+
+.. function:: get_special_folder_path(csidl_string)
+
+ This function can be used to retrieve special folder locations on Windows like
+ the Start Menu or the Desktop. It returns the full path to the folder.
+ *csidl_string* must be one of the following strings::
+
+ "CSIDL_APPDATA"
+
+ "CSIDL_COMMON_STARTMENU"
+ "CSIDL_STARTMENU"
+
+ "CSIDL_COMMON_DESKTOPDIRECTORY"
+ "CSIDL_DESKTOPDIRECTORY"
+
+ "CSIDL_COMMON_STARTUP"
+ "CSIDL_STARTUP"
+
+ "CSIDL_COMMON_PROGRAMS"
+ "CSIDL_PROGRAMS"
+
+ "CSIDL_FONTS"
+
+ If the folder cannot be retrieved, :exc:`OSError` is raised.
+
+ Which folders are available depends on the exact Windows version, and probably
+ also the configuration. For details refer to Microsoft's documentation of the
+ :cfunc:`SHGetSpecialFolderPath` function.
+
+
+.. function:: create_shortcut(target, description, filename[, arguments[, workdir[, iconpath[, iconindex]]]])
+
+ This function creates a shortcut. *target* is the path to the program to be
+ started by the shortcut. *description* is the description of the shortcut.
+ *filename* is the title of the shortcut that the user will see. *arguments*
+ specifies the command line arguments, if any. *workdir* is the working directory
+ for the program. *iconpath* is the file containing the icon for the shortcut,
+ and *iconindex* is the index of the icon in the file *iconpath*. Again, for
+ details consult the Microsoft documentation for the :class:`IShellLink`
+ interface.
+
+
diff --git a/Doc/distutils/commandref.rst b/Doc/distutils/commandref.rst
new file mode 100644
index 0000000000..f5f02204c5
--- /dev/null
+++ b/Doc/distutils/commandref.rst
@@ -0,0 +1,104 @@
+.. _reference:
+
+*****************
+Command Reference
+*****************
+
+.. % \section{Building modules: the \protect\command{build} command family}
+.. % \label{build-cmds}
+.. % \subsubsection{\protect\command{build}}
+.. % \label{build-cmd}
+.. % \subsubsection{\protect\command{build\_py}}
+.. % \label{build-py-cmd}
+.. % \subsubsection{\protect\command{build\_ext}}
+.. % \label{build-ext-cmd}
+.. % \subsubsection{\protect\command{build\_clib}}
+.. % \label{build-clib-cmd}
+
+
+.. _install-cmd:
+
+Installing modules: the :command:`install` command family
+=========================================================
+
+The install command ensures that the build commands have been run and then runs
+the subcommands :command:`install_lib`, :command:`install_data` and
+:command:`install_scripts`.
+
+.. % \subsubsection{\protect\command{install\_lib}}
+.. % \label{install-lib-cmd}
+
+
+.. _install-data-cmd:
+
+:command:`install_data`
+-----------------------
+
+This command installs all data files provided with the distribution.
+
+
+.. _install-scripts-cmd:
+
+:command:`install_scripts`
+--------------------------
+
+This command installs all (Python) scripts in the distribution.
+
+.. % \subsection{Cleaning up: the \protect\command{clean} command}
+.. % \label{clean-cmd}
+
+
+.. _sdist-cmd:
+
+Creating a source distribution: the :command:`sdist` command
+============================================================
+
+**\*\*** fragment moved down from above: needs context! **\*\***
+
+The manifest template commands are:
+
++-------------------------------------------+-----------------------------------------------+
+| Command | Description |
++===========================================+===============================================+
+| :command:`include pat1 pat2 ...` | include all files matching any of the listed |
+| | patterns |
++-------------------------------------------+-----------------------------------------------+
+| :command:`exclude pat1 pat2 ...` | exclude all files matching any of the listed |
+| | patterns |
++-------------------------------------------+-----------------------------------------------+
+| :command:`recursive-include dir pat1 pat2 | include all files under *dir* matching any of |
+| ...` | the listed patterns |
++-------------------------------------------+-----------------------------------------------+
+| :command:`recursive-exclude dir pat1 pat2 | exclude all files under *dir* matching any of |
+| ...` | the listed patterns |
++-------------------------------------------+-----------------------------------------------+
+| :command:`global-include pat1 pat2 ...` | include all files anywhere in the source tree |
+| | matching --- & any of the listed patterns |
++-------------------------------------------+-----------------------------------------------+
+| :command:`global-exclude pat1 pat2 ...` | exclude all files anywhere in the source tree |
+| | matching --- & any of the listed patterns |
++-------------------------------------------+-----------------------------------------------+
+| :command:`prune dir` | exclude all files under *dir* |
++-------------------------------------------+-----------------------------------------------+
+| :command:`graft dir` | include all files under *dir* |
++-------------------------------------------+-----------------------------------------------+
+
+The patterns here are Unix-style "glob" patterns: ``*`` matches any sequence of
+regular filename characters, ``?`` matches any single regular filename
+character, and ``[range]`` matches any of the characters in *range* (e.g.,
+``a-z``, ``a-zA-Z``, ``a-f0-9_.``). The definition of "regular filename
+character" is platform-specific: on Unix it is anything except slash; on Windows
+anything except backslash or colon; on Mac OS 9 anything except colon.
+
+**\*\*** Windows support not there yet **\*\***
+
+.. % \section{Creating a built distribution: the
+.. % \protect\command{bdist} command family}
+.. % \label{bdist-cmds}
+
+.. % \subsection{\protect\command{bdist}}
+.. % \subsection{\protect\command{bdist\_dumb}}
+.. % \subsection{\protect\command{bdist\_rpm}}
+.. % \subsection{\protect\command{bdist\_wininst}}
+
+
diff --git a/Doc/distutils/configfile.rst b/Doc/distutils/configfile.rst
new file mode 100644
index 0000000000..0ccd5fd3e8
--- /dev/null
+++ b/Doc/distutils/configfile.rst
@@ -0,0 +1,130 @@
+.. _setup-config:
+
+************************************
+Writing the Setup Configuration File
+************************************
+
+Often, it's not possible to write down everything needed to build a distribution
+*a priori*: you may need to get some information from the user, or from the
+user's system, in order to proceed. As long as that information is fairly
+simple---a list of directories to search for C header files or libraries, for
+example---then providing a configuration file, :file:`setup.cfg`, for users to
+edit is a cheap and easy way to solicit it. Configuration files also let you
+provide default values for any command option, which the installer can then
+override either on the command-line or by editing the config file.
+
+The setup configuration file is a useful middle-ground between the setup script
+---which, ideally, would be opaque to installers [#]_---and the command-line to
+the setup script, which is outside of your control and entirely up to the
+installer. In fact, :file:`setup.cfg` (and any other Distutils configuration
+files present on the target system) are processed after the contents of the
+setup script, but before the command-line. This has several useful
+consequences:
+
+.. % (If you have more advanced needs, such as determining which extensions
+.. % to build based on what capabilities are present on the target system,
+.. % then you need the Distutils ``auto-configuration'' facility. This
+.. % started to appear in Distutils 0.9 but, as of this writing, isn't mature
+.. % or stable enough yet for real-world use.)
+
+* installers can override some of what you put in :file:`setup.py` by editing
+ :file:`setup.cfg`
+
+* you can provide non-standard defaults for options that are not easily set in
+ :file:`setup.py`
+
+* installers can override anything in :file:`setup.cfg` using the command-line
+ options to :file:`setup.py`
+
+The basic syntax of the configuration file is simple::
+
+ [command]
+ option=value
+ ...
+
+where *command* is one of the Distutils commands (e.g. :command:`build_py`,
+:command:`install`), and *option* is one of the options that command supports.
+Any number of options can be supplied for each command, and any number of
+command sections can be included in the file. Blank lines are ignored, as are
+comments, which run from a ``'#'`` character until the end of the line. Long
+option values can be split across multiple lines simply by indenting the
+continuation lines.
+
+You can find out the list of options supported by a particular command with the
+universal :option:`--help` option, e.g. ::
+
+ > python setup.py --help build_ext
+ [...]
+ Options for 'build_ext' command:
+ --build-lib (-b) directory for compiled extension modules
+ --build-temp (-t) directory for temporary files (build by-products)
+ --inplace (-i) ignore build-lib and put compiled extensions into the
+ source directory alongside your pure Python modules
+ --include-dirs (-I) list of directories to search for header files
+ --define (-D) C preprocessor macros to define
+ --undef (-U) C preprocessor macros to undefine
+ --swig-opts list of SWIG command line options
+ [...]
+
+Note that an option spelled :option:`--foo-bar` on the command-line is spelled
+:option:`foo_bar` in configuration files.
+
+For example, say you want your extensions to be built "in-place"---that is, you
+have an extension :mod:`pkg.ext`, and you want the compiled extension file
+(:file:`ext.so` on Unix, say) to be put in the same source directory as your
+pure Python modules :mod:`pkg.mod1` and :mod:`pkg.mod2`. You can always use the
+:option:`--inplace` option on the command-line to ensure this::
+
+ python setup.py build_ext --inplace
+
+But this requires that you always specify the :command:`build_ext` command
+explicitly, and remember to provide :option:`--inplace`. An easier way is to
+"set and forget" this option, by encoding it in :file:`setup.cfg`, the
+configuration file for this distribution::
+
+ [build_ext]
+ inplace=1
+
+This will affect all builds of this module distribution, whether or not you
+explicitly specify :command:`build_ext`. If you include :file:`setup.cfg` in
+your source distribution, it will also affect end-user builds---which is
+probably a bad idea for this option, since always building extensions in-place
+would break installation of the module distribution. In certain peculiar cases,
+though, modules are built right in their installation directory, so this is
+conceivably a useful ability. (Distributing extensions that expect to be built
+in their installation directory is almost always a bad idea, though.)
+
+Another example: certain commands take a lot of options that don't change from
+run to run; for example, :command:`bdist_rpm` needs to know everything required
+to generate a "spec" file for creating an RPM distribution. Some of this
+information comes from the setup script, and some is automatically generated by
+the Distutils (such as the list of files installed). But some of it has to be
+supplied as options to :command:`bdist_rpm`, which would be very tedious to do
+on the command-line for every run. Hence, here is a snippet from the Distutils'
+own :file:`setup.cfg`::
+
+ [bdist_rpm]
+ release = 1
+ packager = Greg Ward <gward@python.net>
+ doc_files = CHANGES.txt
+ README.txt
+ USAGE.txt
+ doc/
+ examples/
+
+Note that the :option:`doc_files` option is simply a whitespace-separated string
+split across multiple lines for readability.
+
+
+.. seealso::
+
+ :ref:`inst-config-syntax` in "Installing Python Modules"
+ More information on the configuration files is available in the manual for
+ system administrators.
+
+
+.. rubric:: Footnotes
+
+.. [#] This ideal probably won't be achieved until auto-configuration is fully
+ supported by the Distutils.
+
diff --git a/Doc/distutils/examples.rst b/Doc/distutils/examples.rst
new file mode 100644
index 0000000000..4e4adc56d2
--- /dev/null
+++ b/Doc/distutils/examples.rst
@@ -0,0 +1,241 @@
+.. _examples:
+
+********
+Examples
+********
+
+This chapter provides a number of basic examples to help get started with
+distutils. Additional information about using distutils can be found in the
+Distutils Cookbook.
+
+
+.. seealso::
+
+ `Distutils Cookbook <http://www.python.org/cgi-bin/moinmoin/DistutilsCookbook>`_
+ Collection of recipes showing how to achieve more control over distutils.
+
+
+.. _pure-mod:
+
+Pure Python distribution (by module)
+====================================
+
+If you're just distributing a couple of modules, especially if they don't live
+in a particular package, you can specify them individually using the
+:option:`py_modules` option in the setup script.
+
+In the simplest case, you'll have two files to worry about: a setup script and
+the single module you're distributing, :file:`foo.py` in this example::
+
+ <root>/
+ setup.py
+ foo.py
+
+(In all diagrams in this section, *<root>* will refer to the distribution root
+directory.) A minimal setup script to describe this situation would be::
+
+ from distutils.core import setup
+ setup(name='foo',
+ version='1.0',
+ py_modules=['foo'],
+ )
+
+Note that the name of the distribution is specified independently with the
+:option:`name` option, and there's no rule that says it has to be the same as
+the name of the sole module in the distribution (although that's probably a good
+convention to follow). However, the distribution name is used to generate
+filenames, so you should stick to letters, digits, underscores, and hyphens.
+
+Since :option:`py_modules` is a list, you can of course specify multiple
+modules, eg. if you're distributing modules :mod:`foo` and :mod:`bar`, your
+setup might look like this::
+
+ <root>/
+ setup.py
+ foo.py
+ bar.py
+
+and the setup script might be ::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ py_modules=['foo', 'bar'],
+ )
+
+You can put module source files into another directory, but if you have enough
+modules to do that, it's probably easier to specify modules by package rather
+than listing them individually.
+
+
+.. _pure-pkg:
+
+Pure Python distribution (by package)
+=====================================
+
+If you have more than a couple of modules to distribute, especially if they are
+in multiple packages, it's probably easier to specify whole packages rather than
+individual modules. This works even if your modules are not in a package; you
+can just tell the Distutils to process modules from the root package, and that
+works the same as any other package (except that you don't have to have an
+:file:`__init__.py` file).
+
+The setup script from the last example could also be written as ::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ packages=[''],
+ )
+
+(The empty string stands for the root package.)
+
+If those two files are moved into a subdirectory, but remain in the root
+package, e.g.::
+
+ <root>/
+ setup.py
+ src/ foo.py
+ bar.py
+
+then you would still specify the root package, but you have to tell the
+Distutils where source files in the root package live::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ package_dir={'': 'src'},
+ packages=[''],
+ )
+
+More typically, though, you will want to distribute multiple modules in the same
+package (or in sub-packages). For example, if the :mod:`foo` and :mod:`bar`
+modules belong in package :mod:`foobar`, one way to layout your source tree is
+::
+
+ <root>/
+ setup.py
+ foobar/
+ __init__.py
+ foo.py
+ bar.py
+
+This is in fact the default layout expected by the Distutils, and the one that
+requires the least work to describe in your setup script::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ packages=['foobar'],
+ )
+
+If you want to put modules in directories not named for their package, then you
+need to use the :option:`package_dir` option again. For example, if the
+:file:`src` directory holds modules in the :mod:`foobar` package::
+
+ <root>/
+ setup.py
+ src/
+ __init__.py
+ foo.py
+ bar.py
+
+an appropriate setup script would be ::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ package_dir={'foobar': 'src'},
+ packages=['foobar'],
+ )
+
+Or, you might put modules from your main package right in the distribution
+root::
+
+ <root>/
+ setup.py
+ __init__.py
+ foo.py
+ bar.py
+
+in which case your setup script would be ::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ package_dir={'foobar': ''},
+ packages=['foobar'],
+ )
+
+(The empty string also stands for the current directory.)
+
+If you have sub-packages, they must be explicitly listed in :option:`packages`,
+but any entries in :option:`package_dir` automatically extend to sub-packages.
+(In other words, the Distutils does *not* scan your source tree, trying to
+figure out which directories correspond to Python packages by looking for
+:file:`__init__.py` files.) Thus, if the default layout grows a sub-package::
+
+ <root>/
+ setup.py
+ foobar/
+ __init__.py
+ foo.py
+ bar.py
+ subfoo/
+ __init__.py
+ blah.py
+
+then the corresponding setup script would be ::
+
+ from distutils.core import setup
+ setup(name='foobar',
+ version='1.0',
+ packages=['foobar', 'foobar.subfoo'],
+ )
+
+(Again, the empty string in :option:`package_dir` stands for the current
+directory.)
+
+
+.. _single-ext:
+
+Single extension module
+=======================
+
+Extension modules are specified using the :option:`ext_modules` option.
+:option:`package_dir` has no effect on where extension source files are found;
+it only affects the source for pure Python modules. The simplest case, a
+single extension module in a single C source file, is::
+
+ <root>/
+ setup.py
+ foo.c
+
+If the :mod:`foo` extension belongs in the root package, the setup script for
+this could be ::
+
+ from distutils.core import setup
+ from distutils.extension import Extension
+ setup(name='foobar',
+ version='1.0',
+ ext_modules=[Extension('foo', ['foo.c'])],
+ )
+
+If the extension actually belongs in a package, say :mod:`foopkg`, then
+
+With exactly the same source tree layout, this extension can be put in the
+:mod:`foopkg` package simply by changing the name of the extension::
+
+ from distutils.core import setup
+ from distutils.extension import Extension
+ setup(name='foobar',
+ version='1.0',
+ ext_modules=[Extension('foopkg.foo', ['foo.c'])],
+ )
+
+.. % \section{Multiple extension modules}
+.. % \label{multiple-ext}
+
+.. % \section{Putting it all together}
+
+
diff --git a/Doc/distutils/extending.rst b/Doc/distutils/extending.rst
new file mode 100644
index 0000000000..a2930c77df
--- /dev/null
+++ b/Doc/distutils/extending.rst
@@ -0,0 +1,96 @@
+.. _extending:
+
+*******************
+Extending Distutils
+*******************
+
+Distutils can be extended in various ways. Most extensions take the form of new
+commands or replacements for existing commands. New commands may be written to
+support new types of platform-specific packaging, for example, while
+replacements for existing commands may be made to modify details of how the
+command operates on a package.
+
+Most extensions of the distutils are made within :file:`setup.py` scripts that
+want to modify existing commands; many simply add a few file extensions that
+should be copied into packages in addition to :file:`.py` files as a
+convenience.
+
+Most distutils command implementations are subclasses of the :class:`Command`
+class from :mod:`distutils.cmd`. New commands may directly inherit from
+:class:`Command`, while replacements often derive from :class:`Command`
+indirectly, directly subclassing the command they are replacing. Commands are
+required to derive from :class:`Command`.
+
+.. % \section{Extending existing commands}
+.. % \label{extend-existing}
+
+.. % \section{Writing new commands}
+.. % \label{new-commands}
+.. % \XXX{Would an uninstall command be a good example here?}
+
+
+Integrating new commands
+========================
+
+There are different ways to integrate new command implementations into
+distutils. The most difficult is to lobby for the inclusion of the new features
+in distutils itself, and wait for (and require) a version of Python that
+provides that support. This is really hard for many reasons.
+
+The most common, and possibly the most reasonable for most needs, is to include
+the new implementations with your :file:`setup.py` script, and cause the
+:func:`distutils.core.setup` function use them::
+
+ from distutils.command.build_py import build_py as _build_py
+ from distutils.core import setup
+
+ class build_py(_build_py):
+ """Specialized Python source builder."""
+
+ # implement whatever needs to be different...
+
+ setup(cmdclass={'build_py': build_py},
+ ...)
+
+This approach is most valuable if the new implementations must be used to use a
+particular package, as everyone interested in the package will need to have the
+new command implementation.
+
+Beginning with Python 2.4, a third option is available, intended to allow new
+commands to be added which can support existing :file:`setup.py` scripts without
+requiring modifications to the Python installation. This is expected to allow
+third-party extensions to provide support for additional packaging systems, but
+the commands can be used for anything distutils commands can be used for. A new
+configuration option, :option:`command_packages` (command-line option
+:option:`--command-packages`), can be used to specify additional packages to be
+searched for modules implementing commands. Like all distutils options, this
+can be specified on the command line or in a configuration file. This option
+can only be set in the ``[global]`` section of a configuration file, or before
+any commands on the command line. If set in a configuration file, it can be
+overridden from the command line; setting it to an empty string on the command
+line causes the default to be used. This should never be set in a configuration
+file provided with a package.
+
+This new option can be used to add any number of packages to the list of
+packages searched for command implementations; multiple package names should be
+separated by commas. When not specified, the search is only performed in the
+:mod:`distutils.command` package. When :file:`setup.py` is run with the option
+:option:`--command-packages` :option:`distcmds,buildcmds`, however, the packages
+:mod:`distutils.command`, :mod:`distcmds`, and :mod:`buildcmds` will be searched
+in that order. New commands are expected to be implemented in modules of the
+same name as the command by classes sharing the same name. Given the example
+command line option above, the command :command:`bdist_openpkg` could be
+implemented by the class :class:`distcmds.bdist_openpkg.bdist_openpkg` or
+:class:`buildcmds.bdist_openpkg.bdist_openpkg`.
+
+
+Adding new distribution types
+=============================
+
+Commands that create distributions (files in the :file:`dist/` directory) need
+to add ``(command, filename)`` pairs to ``self.distribution.dist_files`` so that
+:command:`upload` can upload it to PyPI. The *filename* in the pair contains no
+path information, only the name of the file itself. In dry-run mode, pairs
+should still be added to represent what would have been created.
+
+
diff --git a/Doc/distutils/index.rst b/Doc/distutils/index.rst
new file mode 100644
index 0000000000..6d82c847bb
--- /dev/null
+++ b/Doc/distutils/index.rst
@@ -0,0 +1,30 @@
+.. _distutils-index:
+
+###############################
+ Distributing Python Modules
+###############################
+
+:Authors: Greg Ward, Anthony Baxter
+:Email: distutils-sig@python.org
+:Release: |version|
+:Date: |today|
+
+This document describes the Python Distribution Utilities ("Distutils") from
+the module developer's point of view, describing how to use the Distutils to
+make Python modules and extensions easily available to a wider audience with
+very little overhead for build/release/install mechanics.
+
+.. toctree::
+ :maxdepth: 2
+
+ introduction.rst
+ setupscript.rst
+ configfile.rst
+ sourcedist.rst
+ builtdist.rst
+ packageindex.rst
+ uploading.rst
+ examples.rst
+ extending.rst
+ commandref.rst
+ apiref.rst
diff --git a/Doc/distutils/introduction.rst b/Doc/distutils/introduction.rst
new file mode 100644
index 0000000000..b772b01004
--- /dev/null
+++ b/Doc/distutils/introduction.rst
@@ -0,0 +1,208 @@
+.. _distutils-intro:
+
+****************************
+An Introduction to Distutils
+****************************
+
+This document covers using the Distutils to distribute your Python modules,
+concentrating on the role of developer/distributor: if you're looking for
+information on installing Python modules, you should refer to the
+:ref:`install-index` chapter.
+
+
+.. _distutils-concepts:
+
+Concepts & Terminology
+======================
+
+Using the Distutils is quite simple, both for module developers and for
+users/administrators installing third-party modules. As a developer, your
+responsibilities (apart from writing solid, well-documented and well-tested
+code, of course!) are:
+
+* write a setup script (:file:`setup.py` by convention)
+
+* (optional) write a setup configuration file
+
+* create a source distribution
+
+* (optional) create one or more built (binary) distributions
+
+Each of these tasks is covered in this document.
+
+Not all module developers have access to a multitude of platforms, so it's not
+always feasible to expect them to create a multitude of built distributions. It
+is hoped that a class of intermediaries, called *packagers*, will arise to
+address this need. Packagers will take source distributions released by module
+developers, build them on one or more platforms, and release the resulting built
+distributions. Thus, users on the most popular platforms will be able to
+install most popular Python module distributions in the most natural way for
+their platform, without having to run a single setup script or compile a line of
+code.
+
+
+.. _distutils-simple-example:
+
+A Simple Example
+================
+
+The setup script is usually quite simple, although since it's written in Python,
+there are no arbitrary limits to what you can do with it, though you should be
+careful about putting arbitrarily expensive operations in your setup script.
+Unlike, say, Autoconf-style configure scripts, the setup script may be run
+multiple times in the course of building and installing your module
+distribution.
+
+If all you want to do is distribute a module called :mod:`foo`, contained in a
+file :file:`foo.py`, then your setup script can be as simple as this::
+
+ from distutils.core import setup
+ setup(name='foo',
+ version='1.0',
+ py_modules=['foo'],
+ )
+
+Some observations:
+
+* most information that you supply to the Distutils is supplied as keyword
+ arguments to the :func:`setup` function
+
+* those keyword arguments fall into two categories: package metadata (name,
+ version number) and information about what's in the package (a list of pure
+ Python modules, in this case)
+
+* modules are specified by module name, not filename (the same will hold true
+ for packages and extensions)
+
+* it's recommended that you supply a little more metadata, in particular your
+ name, email address and a URL for the project (see section :ref:`setup-script`
+ for an example)
+
+To create a source distribution for this module, you would create a setup
+script, :file:`setup.py`, containing the above code, and run::
+
+ python setup.py sdist
+
+which will create an archive file (e.g., tarball on Unix, ZIP file on Windows)
+containing your setup script :file:`setup.py`, and your module :file:`foo.py`.
+The archive file will be named :file:`foo-1.0.tar.gz` (or :file:`.zip`), and
+will unpack into a directory :file:`foo-1.0`.
+
+If an end-user wishes to install your :mod:`foo` module, all she has to do is
+download :file:`foo-1.0.tar.gz` (or :file:`.zip`), unpack it, and---from the
+:file:`foo-1.0` directory---run ::
+
+ python setup.py install
+
+which will ultimately copy :file:`foo.py` to the appropriate directory for
+third-party modules in their Python installation.
+
+This simple example demonstrates some fundamental concepts of the Distutils.
+First, both developers and installers have the same basic user interface, i.e.
+the setup script. The difference is which Distutils *commands* they use: the
+:command:`sdist` command is almost exclusively for module developers, while
+:command:`install` is more often for installers (although most developers will
+want to install their own code occasionally).
+
+If you want to make things really easy for your users, you can create one or
+more built distributions for them. For instance, if you are running on a
+Windows machine, and want to make things easy for other Windows users, you can
+create an executable installer (the most appropriate type of built distribution
+for this platform) with the :command:`bdist_wininst` command. For example::
+
+ python setup.py bdist_wininst
+
+will create an executable installer, :file:`foo-1.0.win32.exe`, in the current
+directory.
+
+Other useful built distribution formats are RPM, implemented by the
+:command:`bdist_rpm` command, Solaris :program:`pkgtool`
+(:command:`bdist_pkgtool`), and HP-UX :program:`swinstall`
+(:command:`bdist_sdux`). For example, the following command will create an RPM
+file called :file:`foo-1.0.noarch.rpm`::
+
+ python setup.py bdist_rpm
+
+(The :command:`bdist_rpm` command uses the :command:`rpm` executable, therefore
+this has to be run on an RPM-based system such as Red Hat Linux, SuSE Linux, or
+Mandrake Linux.)
+
+You can find out what distribution formats are available at any time by running
+::
+
+ python setup.py bdist --help-formats
+
+
+.. _python-terms:
+
+General Python terminology
+==========================
+
+If you're reading this document, you probably have a good idea of what modules,
+extensions, and so forth are. Nevertheless, just to be sure that everyone is
+operating from a common starting point, we offer the following glossary of
+common Python terms:
+
+module
+ the basic unit of code reusability in Python: a block of code imported by some
+ other code. Three types of modules concern us here: pure Python modules,
+ extension modules, and packages.
+
+pure Python module
+ a module written in Python and contained in a single :file:`.py` file (and
+ possibly associated :file:`.pyc` and/or :file:`.pyo` files). Sometimes referred
+ to as a "pure module."
+
+extension module
+ a module written in the low-level language of the Python implementation: C/C++
+ for Python, Java for Jython. Typically contained in a single dynamically
+ loadable pre-compiled file, e.g. a shared object (:file:`.so`) file for Python
+ extensions on Unix, a DLL (given the :file:`.pyd` extension) for Python
+ extensions on Windows, or a Java class file for Jython extensions. (Note that
+ currently, the Distutils only handles C/C++ extensions for Python.)
+
+package
+ a module that contains other modules; typically contained in a directory in the
+ filesystem and distinguished from other directories by the presence of a file
+ :file:`__init__.py`.
+
+root package
+ the root of the hierarchy of packages. (This isn't really a package, since it
+ doesn't have an :file:`__init__.py` file. But we have to call it something.)
+ The vast majority of the standard library is in the root package, as are many
+ small, standalone third-party modules that don't belong to a larger module
+ collection. Unlike regular packages, modules in the root package can be found in
+ many directories: in fact, every directory listed in ``sys.path`` contributes
+ modules to the root package.
+
+
+.. _distutils-term:
+
+Distutils-specific terminology
+==============================
+
+The following terms apply more specifically to the domain of distributing Python
+modules using the Distutils:
+
+module distribution
+ a collection of Python modules distributed together as a single downloadable
+ resource and meant to be installed *en masse*. Examples of some well-known
+ module distributions are Numeric Python, PyXML, PIL (the Python Imaging
+ Library), or mxBase. (This would be called a *package*, except that term is
+ already taken in the Python context: a single module distribution may contain
+ zero, one, or many Python packages.)
+
+pure module distribution
+ a module distribution that contains only pure Python modules and packages.
+ Sometimes referred to as a "pure distribution."
+
+non-pure module distribution
+ a module distribution that contains at least one extension module. Sometimes
+ referred to as a "non-pure distribution."
+
+distribution root
+ the top-level directory of your source tree (or source distribution); the
+ directory where :file:`setup.py` exists. Generally :file:`setup.py` will be
+ run from this directory.
+
+
diff --git a/Doc/distutils/packageindex.rst b/Doc/distutils/packageindex.rst
new file mode 100644
index 0000000000..f0f886bcc9
--- /dev/null
+++ b/Doc/distutils/packageindex.rst
@@ -0,0 +1,65 @@
+.. _package-index:
+
+**********************************
+Registering with the Package Index
+**********************************
+
+The Python Package Index (PyPI) holds meta-data describing distributions
+packaged with distutils. The distutils command :command:`register` is used to
+submit your distribution's meta-data to the index. It is invoked as follows::
+
+ python setup.py register
+
+Distutils will respond with the following prompt::
+
+ running register
+ We need to know who you are, so please choose either:
+ 1. use your existing login,
+ 2. register as a new user,
+ 3. have the server generate a new password for you (and email it to you), or
+ 4. quit
+ Your selection [default 1]:
+
+Note: if your username and password are saved locally, you will not see this
+menu.
+
+If you have not registered with PyPI, then you will need to do so now. You
+should choose option 2, and enter your details as required. Soon after
+submitting your details, you will receive an email which will be used to confirm
+your registration.
+
+Once you are registered, you may choose option 1 from the menu. You will be
+prompted for your PyPI username and password, and :command:`register` will then
+submit your meta-data to the index.
+
+You may submit any number of versions of your distribution to the index. If you
+alter the meta-data for a particular version, you may submit it again and the
+index will be updated.
+
+PyPI holds a record for each (name, version) combination submitted. The first
+user to submit information for a given name is designated the Owner of that
+name. They may submit changes through the :command:`register` command or through
+the web interface. They may also designate other users as Owners or Maintainers.
+Maintainers may edit the package information, but not designate other Owners or
+Maintainers.
+
+By default PyPI will list all versions of a given package. To hide certain
+versions, the Hidden property should be set to yes. This must be edited through
+the web interface.
+
+
+.. _pypirc:
+
+The .pypirc file
+================
+
+The format of the :file:`.pypirc` file is formated as follows::
+
+ [server-login]
+ repository: <repository-url>
+ username: <username>
+ password: <password>
+
+*repository* can be ommitted and defaults to ``http://www.python.org/pypi``.
+
+
diff --git a/Doc/distutils/setupscript.rst b/Doc/distutils/setupscript.rst
new file mode 100644
index 0000000000..26f50e6cd5
--- /dev/null
+++ b/Doc/distutils/setupscript.rst
@@ -0,0 +1,669 @@
+.. _setup-script:
+
+************************
+Writing the Setup Script
+************************
+
+The setup script is the centre of all activity in building, distributing, and
+installing modules using the Distutils. The main purpose of the setup script is
+to describe your module distribution to the Distutils, so that the various
+commands that operate on your modules do the right thing. As we saw in section
+:ref:`distutils-simple-example` above, the setup script consists mainly of a call to
+:func:`setup`, and most information supplied to the Distutils by the module
+developer is supplied as keyword arguments to :func:`setup`.
+
+Here's a slightly more involved example, which we'll follow for the next couple
+of sections: the Distutils' own setup script. (Keep in mind that although the
+Distutils are included with Python 1.6 and later, they also have an independent
+existence so that Python 1.5.2 users can use them to install other module
+distributions. The Distutils' own setup script, shown here, is used to install
+the package into Python 1.5.2.) ::
+
+ #!/usr/bin/env python
+
+ from distutils.core import setup
+
+ setup(name='Distutils',
+ version='1.0',
+ description='Python Distribution Utilities',
+ author='Greg Ward',
+ author_email='gward@python.net',
+ url='http://www.python.org/sigs/distutils-sig/',
+ packages=['distutils', 'distutils.command'],
+ )
+
+There are only two differences between this and the trivial one-file
+distribution presented in section :ref:`distutils-simple-example`: more metadata, and the
+specification of pure Python modules by package, rather than by module. This is
+important since the Distutils consist of a couple of dozen modules split into
+(so far) two packages; an explicit list of every module would be tedious to
+generate and difficult to maintain. For more information on the additional
+meta-data, see section :ref:`meta-data`.
+
+Note that any pathnames (files or directories) supplied in the setup script
+should be written using the Unix convention, i.e. slash-separated. The
+Distutils will take care of converting this platform-neutral representation into
+whatever is appropriate on your current platform before actually using the
+pathname. This makes your setup script portable across operating systems, which
+of course is one of the major goals of the Distutils. In this spirit, all
+pathnames in this document are slash-separated. (Mac OS 9 programmers should
+keep in mind that the *absence* of a leading slash indicates a relative path,
+the opposite of the Mac OS convention with colons.)
+
+This, of course, only applies to pathnames given to Distutils functions. If
+you, for example, use standard Python functions such as :func:`glob.glob` or
+:func:`os.listdir` to specify files, you should be careful to write portable
+code instead of hardcoding path separators::
+
+ glob.glob(os.path.join('mydir', 'subdir', '*.html'))
+ os.listdir(os.path.join('mydir', 'subdir'))
+
+
+.. _listing-packages:
+
+Listing whole packages
+======================
+
+The :option:`packages` option tells the Distutils to process (build, distribute,
+install, etc.) all pure Python modules found in each package mentioned in the
+:option:`packages` list. In order to do this, of course, there has to be a
+correspondence between package names and directories in the filesystem. The
+default correspondence is the most obvious one, i.e. package :mod:`distutils` is
+found in the directory :file:`distutils` relative to the distribution root.
+Thus, when you say ``packages = ['foo']`` in your setup script, you are
+promising that the Distutils will find a file :file:`foo/__init__.py` (which
+might be spelled differently on your system, but you get the idea) relative to
+the directory where your setup script lives. If you break this promise, the
+Distutils will issue a warning but still process the broken package anyways.
+
+If you use a different convention to lay out your source directory, that's no
+problem: you just have to supply the :option:`package_dir` option to tell the
+Distutils about your convention. For example, say you keep all Python source
+under :file:`lib`, so that modules in the "root package" (i.e., not in any
+package at all) are in :file:`lib`, modules in the :mod:`foo` package are in
+:file:`lib/foo`, and so forth. Then you would put ::
+
+ package_dir = {'': 'lib'}
+
+in your setup script. The keys to this dictionary are package names, and an
+empty package name stands for the root package. The values are directory names
+relative to your distribution root. In this case, when you say ``packages =
+['foo']``, you are promising that the file :file:`lib/foo/__init__.py` exists.
+
+Another possible convention is to put the :mod:`foo` package right in
+:file:`lib`, the :mod:`foo.bar` package in :file:`lib/bar`, etc. This would be
+written in the setup script as ::
+
+ package_dir = {'foo': 'lib'}
+
+A ``package: dir`` entry in the :option:`package_dir` dictionary implicitly
+applies to all packages below *package*, so the :mod:`foo.bar` case is
+automatically handled here. In this example, having ``packages = ['foo',
+'foo.bar']`` tells the Distutils to look for :file:`lib/__init__.py` and
+:file:`lib/bar/__init__.py`. (Keep in mind that although :option:`package_dir`
+applies recursively, you must explicitly list all packages in
+:option:`packages`: the Distutils will *not* recursively scan your source tree
+looking for any directory with an :file:`__init__.py` file.)
+
+
+.. _listing-modules:
+
+Listing individual modules
+==========================
+
+For a small module distribution, you might prefer to list all modules rather
+than listing packages---especially the case of a single module that goes in the
+"root package" (i.e., no package at all). This simplest case was shown in
+section :ref:`distutils-simple-example`; here is a slightly more involved example::
+
+ py_modules = ['mod1', 'pkg.mod2']
+
+This describes two modules, one of them in the "root" package, the other in the
+:mod:`pkg` package. Again, the default package/directory layout implies that
+these two modules can be found in :file:`mod1.py` and :file:`pkg/mod2.py`, and
+that :file:`pkg/__init__.py` exists as well. And again, you can override the
+package/directory correspondence using the :option:`package_dir` option.
+
+
+.. _describing-extensions:
+
+Describing extension modules
+============================
+
+Just as writing Python extension modules is a bit more complicated than writing
+pure Python modules, describing them to the Distutils is a bit more complicated.
+Unlike pure modules, it's not enough just to list modules or packages and expect
+the Distutils to go out and find the right files; you have to specify the
+extension name, source file(s), and any compile/link requirements (include
+directories, libraries to link with, etc.).
+
+.. % XXX read over this section
+
+All of this is done through another keyword argument to :func:`setup`, the
+:option:`ext_modules` option. :option:`ext_modules` is just a list of
+:class:`Extension` instances, each of which describes a single extension module.
+Suppose your distribution includes a single extension, called :mod:`foo` and
+implemented by :file:`foo.c`. If no additional instructions to the
+compiler/linker are needed, describing this extension is quite simple::
+
+ Extension('foo', ['foo.c'])
+
+The :class:`Extension` class can be imported from :mod:`distutils.core` along
+with :func:`setup`. Thus, the setup script for a module distribution that
+contains only this one extension and nothing else might be::
+
+ from distutils.core import setup, Extension
+ setup(name='foo',
+ version='1.0',
+ ext_modules=[Extension('foo', ['foo.c'])],
+ )
+
+The :class:`Extension` class (actually, the underlying extension-building
+machinery implemented by the :command:`build_ext` command) supports a great deal
+of flexibility in describing Python extensions, which is explained in the
+following sections.
+
+
+Extension names and packages
+----------------------------
+
+The first argument to the :class:`Extension` constructor is always the name of
+the extension, including any package names. For example, ::
+
+ Extension('foo', ['src/foo1.c', 'src/foo2.c'])
+
+describes an extension that lives in the root package, while ::
+
+ Extension('pkg.foo', ['src/foo1.c', 'src/foo2.c'])
+
+describes the same extension in the :mod:`pkg` package. The source files and
+resulting object code are identical in both cases; the only difference is where
+in the filesystem (and therefore where in Python's namespace hierarchy) the
+resulting extension lives.
+
+If you have a number of extensions all in the same package (or all under the
+same base package), use the :option:`ext_package` keyword argument to
+:func:`setup`. For example, ::
+
+ setup(...
+ ext_package='pkg',
+ ext_modules=[Extension('foo', ['foo.c']),
+ Extension('subpkg.bar', ['bar.c'])],
+ )
+
+will compile :file:`foo.c` to the extension :mod:`pkg.foo`, and :file:`bar.c` to
+:mod:`pkg.subpkg.bar`.
+
+
+Extension source files
+----------------------
+
+The second argument to the :class:`Extension` constructor is a list of source
+files. Since the Distutils currently only support C, C++, and Objective-C
+extensions, these are normally C/C++/Objective-C source files. (Be sure to use
+appropriate extensions to distinguish C++\ source files: :file:`.cc` and
+:file:`.cpp` seem to be recognized by both Unix and Windows compilers.)
+
+However, you can also include SWIG interface (:file:`.i`) files in the list; the
+:command:`build_ext` command knows how to deal with SWIG extensions: it will run
+SWIG on the interface file and compile the resulting C/C++ file into your
+extension.
+
+**\*\*** SWIG support is rough around the edges and largely untested! **\*\***
+
+This warning notwithstanding, options to SWIG can be currently passed like
+this::
+
+ setup(...
+ ext_modules=[Extension('_foo', ['foo.i'],
+ swig_opts=['-modern', '-I../include'])],
+ py_modules=['foo'],
+ )
+
+Or on the commandline like this::
+
+ > python setup.py build_ext --swig-opts="-modern -I../include"
+
+On some platforms, you can include non-source files that are processed by the
+compiler and included in your extension. Currently, this just means Windows
+message text (:file:`.mc`) files and resource definition (:file:`.rc`) files for
+Visual C++. These will be compiled to binary resource (:file:`.res`) files and
+linked into the executable.
+
+
+Preprocessor options
+--------------------
+
+Three optional arguments to :class:`Extension` will help if you need to specify
+include directories to search or preprocessor macros to define/undefine:
+``include_dirs``, ``define_macros``, and ``undef_macros``.
+
+For example, if your extension requires header files in the :file:`include`
+directory under your distribution root, use the ``include_dirs`` option::
+
+ Extension('foo', ['foo.c'], include_dirs=['include'])
+
+You can specify absolute directories there; if you know that your extension will
+only be built on Unix systems with X11R6 installed to :file:`/usr`, you can get
+away with ::
+
+ Extension('foo', ['foo.c'], include_dirs=['/usr/include/X11'])
+
+You should avoid this sort of non-portable usage if you plan to distribute your
+code: it's probably better to write C code like ::
+
+ #include <X11/Xlib.h>
+
+If you need to include header files from some other Python extension, you can
+take advantage of the fact that header files are installed in a consistent way
+by the Distutils :command:`install_header` command. For example, the Numerical
+Python header files are installed (on a standard Unix installation) to
+:file:`/usr/local/include/python1.5/Numerical`. (The exact location will differ
+according to your platform and Python installation.) Since the Python include
+directory---\ :file:`/usr/local/include/python1.5` in this case---is always
+included in the search path when building Python extensions, the best approach
+is to write C code like ::
+
+ #include <Numerical/arrayobject.h>
+
+If you must put the :file:`Numerical` include directory right into your header
+search path, though, you can find that directory using the Distutils
+:mod:`distutils.sysconfig` module::
+
+ from distutils.sysconfig import get_python_inc
+ incdir = os.path.join(get_python_inc(plat_specific=1), 'Numerical')
+ setup(...,
+ Extension(..., include_dirs=[incdir]),
+ )
+
+Even though this is quite portable---it will work on any Python installation,
+regardless of platform---it's probably easier to just write your C code in the
+sensible way.
+
+You can define and undefine pre-processor macros with the ``define_macros`` and
+``undef_macros`` options. ``define_macros`` takes a list of ``(name, value)``
+tuples, where ``name`` is the name of the macro to define (a string) and
+``value`` is its value: either a string or ``None``. (Defining a macro ``FOO``
+to ``None`` is the equivalent of a bare ``#define FOO`` in your C source: with
+most compilers, this sets ``FOO`` to the string ``1``.) ``undef_macros`` is
+just a list of macros to undefine.
+
+For example::
+
+ Extension(...,
+ define_macros=[('NDEBUG', '1'),
+ ('HAVE_STRFTIME', None)],
+ undef_macros=['HAVE_FOO', 'HAVE_BAR'])
+
+is the equivalent of having this at the top of every C source file::
+
+ #define NDEBUG 1
+ #define HAVE_STRFTIME
+ #undef HAVE_FOO
+ #undef HAVE_BAR
+
+
+Library options
+---------------
+
+You can also specify the libraries to link against when building your extension,
+and the directories to search for those libraries. The ``libraries`` option is
+a list of libraries to link against, ``library_dirs`` is a list of directories
+to search for libraries at link-time, and ``runtime_library_dirs`` is a list of
+directories to search for shared (dynamically loaded) libraries at run-time.
+
+For example, if you need to link against libraries known to be in the standard
+library search path on target systems ::
+
+ Extension(...,
+ libraries=['gdbm', 'readline'])
+
+If you need to link with libraries in a non-standard location, you'll have to
+include the location in ``library_dirs``::
+
+ Extension(...,
+ library_dirs=['/usr/X11R6/lib'],
+ libraries=['X11', 'Xt'])
+
+(Again, this sort of non-portable construct should be avoided if you intend to
+distribute your code.)
+
+**\*\*** Should mention clib libraries here or somewhere else! **\*\***
+
+
+Other options
+-------------
+
+There are still some other options which can be used to handle special cases.
+
+The :option:`extra_objects` option is a list of object files to be passed to the
+linker. These files must not have extensions, as the default extension for the
+compiler is used.
+
+:option:`extra_compile_args` and :option:`extra_link_args` can be used to
+specify additional command line options for the respective compiler and linker
+command lines.
+
+:option:`export_symbols` is only useful on Windows. It can contain a list of
+symbols (functions or variables) to be exported. This option is not needed when
+building compiled extensions: Distutils will automatically add ``initmodule``
+to the list of exported symbols.
+
+
+Relationships between Distributions and Packages
+================================================
+
+A distribution may relate to packages in three specific ways:
+
+#. It can require packages or modules.
+
+#. It can provide packages or modules.
+
+#. It can obsolete packages or modules.
+
+These relationships can be specified using keyword arguments to the
+:func:`distutils.core.setup` function.
+
+Dependencies on other Python modules and packages can be specified by supplying
+the *requires* keyword argument to :func:`setup`. The value must be a list of
+strings. Each string specifies a package that is required, and optionally what
+versions are sufficient.
+
+To specify that any version of a module or package is required, the string
+should consist entirely of the module or package name. Examples include
+``'mymodule'`` and ``'xml.parsers.expat'``.
+
+If specific versions are required, a sequence of qualifiers can be supplied in
+parentheses. Each qualifier may consist of a comparison operator and a version
+number. The accepted comparison operators are::
+
+ < > ==
+ <= >= !=
+
+These can be combined by using multiple qualifiers separated by commas (and
+optional whitespace). In this case, all of the qualifiers must be matched; a
+logical AND is used to combine the evaluations.
+
+Let's look at a bunch of examples:
+
++-------------------------+----------------------------------------------+
+| Requires Expression | Explanation |
++=========================+==============================================+
+| ``==1.0`` | Only version ``1.0`` is compatible |
++-------------------------+----------------------------------------------+
+| ``>1.0, !=1.5.1, <2.0`` | Any version after ``1.0`` and before ``2.0`` |
+| | is compatible, except ``1.5.1`` |
++-------------------------+----------------------------------------------+
+
+Now that we can specify dependencies, we also need to be able to specify what we
+provide that other distributions can require. This is done using the *provides*
+keyword argument to :func:`setup`. The value for this keyword is a list of
+strings, each of which names a Python module or package, and optionally
+identifies the version. If the version is not specified, it is assumed to match
+that of the distribution.
+
+Some examples:
+
++---------------------+----------------------------------------------+
+| Provides Expression | Explanation |
++=====================+==============================================+
+| ``mypkg`` | Provide ``mypkg``, using the distribution |
+| | version |
++---------------------+----------------------------------------------+
+| ``mypkg (1.1)`` | Provide ``mypkg`` version 1.1, regardless of |
+| | the distribution version |
++---------------------+----------------------------------------------+
+
+A package can declare that it obsoletes other packages using the *obsoletes*
+keyword argument. The value for this is similar to that of the *requires*
+keyword: a list of strings giving module or package specifiers. Each specifier
+consists of a module or package name optionally followed by one or more version
+qualifiers. Version qualifiers are given in parentheses after the module or
+package name.
+
+The versions identified by the qualifiers are those that are obsoleted by the
+distribution being described. If no qualifiers are given, all versions of the
+named module or package are understood to be obsoleted.
+
+
+Installing Scripts
+==================
+
+So far we have been dealing with pure and non-pure Python modules, which are
+usually not run by themselves but imported by scripts.
+
+Scripts are files containing Python source code, intended to be started from the
+command line. Scripts don't require Distutils to do anything very complicated.
+The only clever feature is that if the first line of the script starts with
+``#!`` and contains the word "python", the Distutils will adjust the first line
+to refer to the current interpreter location. By default, it is replaced with
+the current interpreter location. The :option:`--executable` (or :option:`-e`)
+option will allow the interpreter path to be explicitly overridden.
+
+The :option:`scripts` option simply is a list of files to be handled in this
+way. From the PyXML setup script::
+
+ setup(...
+ scripts=['scripts/xmlproc_parse', 'scripts/xmlproc_val']
+ )
+
+
+Installing Package Data
+=======================
+
+Often, additional files need to be installed into a package. These files are
+often data that's closely related to the package's implementation, or text files
+containing documentation that might be of interest to programmers using the
+package. These files are called :dfn:`package data`.
+
+Package data can be added to packages using the ``package_data`` keyword
+argument to the :func:`setup` function. The value must be a mapping from
+package name to a list of relative path names that should be copied into the
+package. The paths are interpreted as relative to the directory containing the
+package (information from the ``package_dir`` mapping is used if appropriate);
+that is, the files are expected to be part of the package in the source
+directories. They may contain glob patterns as well.
+
+The path names may contain directory portions; any necessary directories will be
+created in the installation.
+
+For example, if a package should contain a subdirectory with several data files,
+the files can be arranged like this in the source tree::
+
+ setup.py
+ src/
+ mypkg/
+ __init__.py
+ module.py
+ data/
+ tables.dat
+ spoons.dat
+ forks.dat
+
+The corresponding call to :func:`setup` might be::
+
+ setup(...,
+ packages=['mypkg'],
+ package_dir={'mypkg': 'src/mypkg'},
+ package_data={'mypkg': ['data/*.dat']},
+ )
+
+.. versionadded:: 2.4
+
+
+Installing Additional Files
+===========================
+
+The :option:`data_files` option can be used to specify additional files needed
+by the module distribution: configuration files, message catalogs, data files,
+anything which doesn't fit in the previous categories.
+
+:option:`data_files` specifies a sequence of (*directory*, *files*) pairs in the
+following way::
+
+ setup(...
+ data_files=[('bitmaps', ['bm/b1.gif', 'bm/b2.gif']),
+ ('config', ['cfg/data.cfg']),
+ ('/etc/init.d', ['init-script'])]
+ )
+
+Note that you can specify the directory names where the data files will be
+installed, but you cannot rename the data files themselves.
+
+Each (*directory*, *files*) pair in the sequence specifies the installation
+directory and the files to install there. If *directory* is a relative path, it
+is interpreted relative to the installation prefix (Python's ``sys.prefix`` for
+pure-Python packages, ``sys.exec_prefix`` for packages that contain extension
+modules). Each file name in *files* is interpreted relative to the
+:file:`setup.py` script at the top of the package source distribution. No
+directory information from *files* is used to determine the final location of
+the installed file; only the name of the file is used.
+
+You can specify the :option:`data_files` options as a simple sequence of files
+without specifying a target directory, but this is not recommended, and the
+:command:`install` command will print a warning in this case. To install data
+files directly in the target directory, an empty string should be given as the
+directory.
+
+
+.. _meta-data:
+
+Additional meta-data
+====================
+
+The setup script may include additional meta-data beyond the name and version.
+This information includes:
+
++----------------------+---------------------------+-----------------+--------+
+| Meta-Data | Description | Value | Notes |
++======================+===========================+=================+========+
+| ``name`` | name of the package | short string | \(1) |
++----------------------+---------------------------+-----------------+--------+
+| ``version`` | version of this release | short string | (1)(2) |
++----------------------+---------------------------+-----------------+--------+
+| ``author`` | package author's name | short string | \(3) |
++----------------------+---------------------------+-----------------+--------+
+| ``author_email`` | email address of the | email address | \(3) |
+| | package author | | |
++----------------------+---------------------------+-----------------+--------+
+| ``maintainer`` | package maintainer's name | short string | \(3) |
++----------------------+---------------------------+-----------------+--------+
+| ``maintainer_email`` | email address of the | email address | \(3) |
+| | package maintainer | | |
++----------------------+---------------------------+-----------------+--------+
+| ``url`` | home page for the package | URL | \(1) |
++----------------------+---------------------------+-----------------+--------+
+| ``description`` | short, summary | short string | |
+| | description of the | | |
+| | package | | |
++----------------------+---------------------------+-----------------+--------+
+| ``long_description`` | longer description of the | long string | |
+| | package | | |
++----------------------+---------------------------+-----------------+--------+
+| ``download_url`` | location where the | URL | \(4) |
+| | package may be downloaded | | |
++----------------------+---------------------------+-----------------+--------+
+| ``classifiers`` | a list of classifiers | list of strings | \(4) |
++----------------------+---------------------------+-----------------+--------+
+
+Notes:
+
+(1)
+ These fields are required.
+
+(2)
+ It is recommended that versions take the form *major.minor[.patch[.sub]]*.
+
+(3)
+ Either the author or the maintainer must be identified.
+
+(4)
+ These fields should not be used if your package is to be compatible with Python
+ versions prior to 2.2.3 or 2.3. The list is available from the `PyPI website
+ <http://www.python.org/pypi>`_.
+
+'short string'
+ A single line of text, not more than 200 characters.
+
+'long string'
+ Multiple lines of plain text in reStructuredText format (see
+ http://docutils.sf.net/).
+
+'list of strings'
+ See below.
+
+None of the string values may be Unicode.
+
+Encoding the version information is an art in itself. Python packages generally
+adhere to the version format *major.minor[.patch][sub]*. The major number is 0
+for initial, experimental releases of software. It is incremented for releases
+that represent major milestones in a package. The minor number is incremented
+when important new features are added to the package. The patch number
+increments when bug-fix releases are made. Additional trailing version
+information is sometimes used to indicate sub-releases. These are
+"a1,a2,...,aN" (for alpha releases, where functionality and API may change),
+"b1,b2,...,bN" (for beta releases, which only fix bugs) and "pr1,pr2,...,prN"
+(for final pre-release release testing). Some examples:
+
+0.1.0
+ the first, experimental release of a package
+
+1.0.1a2
+ the second alpha release of the first patch version of 1.0
+
+:option:`classifiers` are specified in a python list::
+
+ setup(...
+ classifiers=[
+ 'Development Status :: 4 - Beta',
+ 'Environment :: Console',
+ 'Environment :: Web Environment',
+ 'Intended Audience :: End Users/Desktop',
+ 'Intended Audience :: Developers',
+ 'Intended Audience :: System Administrators',
+ 'License :: OSI Approved :: Python Software Foundation License',
+ 'Operating System :: MacOS :: MacOS X',
+ 'Operating System :: Microsoft :: Windows',
+ 'Operating System :: POSIX',
+ 'Programming Language :: Python',
+ 'Topic :: Communications :: Email',
+ 'Topic :: Office/Business',
+ 'Topic :: Software Development :: Bug Tracking',
+ ],
+ )
+
+If you wish to include classifiers in your :file:`setup.py` file and also wish
+to remain backwards-compatible with Python releases prior to 2.2.3, then you can
+include the following code fragment in your :file:`setup.py` before the
+:func:`setup` call. ::
+
+ # patch distutils if it can't cope with the "classifiers" or
+ # "download_url" keywords
+ from sys import version
+ if version < '2.2.3':
+ from distutils.dist import DistributionMetadata
+ DistributionMetadata.classifiers = None
+ DistributionMetadata.download_url = None
+
+
+Debugging the setup script
+==========================
+
+Sometimes things go wrong, and the setup script doesn't do what the developer
+wants.
+
+Distutils catches any exceptions when running the setup script, and print a
+simple error message before the script is terminated. The motivation for this
+behaviour is to not confuse administrators who don't know much about Python and
+are trying to install a package. If they get a big long traceback from deep
+inside the guts of Distutils, they may think the package or the Python
+installation is broken because they don't read all the way down to the bottom
+and see that it's a permission problem.
+
+On the other hand, this doesn't help the developer to find the cause of the
+failure. For this purpose, the DISTUTILS_DEBUG environment variable can be set
+to anything except an empty string, and distutils will now print detailed
+information what it is doing, and prints the full traceback in case an exception
+occurs.
+
+
diff --git a/Doc/distutils/sourcedist.rst b/Doc/distutils/sourcedist.rst
new file mode 100644
index 0000000000..9f15870ccd
--- /dev/null
+++ b/Doc/distutils/sourcedist.rst
@@ -0,0 +1,207 @@
+.. _source-dist:
+
+******************************
+Creating a Source Distribution
+******************************
+
+As shown in section :ref:`distutils-simple-example`, you use the :command:`sdist` command
+to create a source distribution. In the simplest case, ::
+
+ python setup.py sdist
+
+(assuming you haven't specified any :command:`sdist` options in the setup script
+or config file), :command:`sdist` creates the archive of the default format for
+the current platform. The default format is a gzip'ed tar file
+(:file:`.tar.gz`) on Unix, and ZIP file on Windows.
+
+You can specify as many formats as you like using the :option:`--formats`
+option, for example::
+
+ python setup.py sdist --formats=gztar,zip
+
+to create a gzipped tarball and a zip file. The available formats are:
+
++-----------+-------------------------+---------+
+| Format | Description | Notes |
++===========+=========================+=========+
+| ``zip`` | zip file (:file:`.zip`) | (1),(3) |
++-----------+-------------------------+---------+
+| ``gztar`` | gzip'ed tar file | (2),(4) |
+| | (:file:`.tar.gz`) | |
++-----------+-------------------------+---------+
+| ``bztar`` | bzip2'ed tar file | \(4) |
+| | (:file:`.tar.bz2`) | |
++-----------+-------------------------+---------+
+| ``ztar`` | compressed tar file | \(4) |
+| | (:file:`.tar.Z`) | |
++-----------+-------------------------+---------+
+| ``tar`` | tar file (:file:`.tar`) | \(4) |
++-----------+-------------------------+---------+
+
+Notes:
+
+(1)
+ default on Windows
+
+(2)
+ default on Unix
+
+(3)
+ requires either external :program:`zip` utility or :mod:`zipfile` module (part
+ of the standard Python library since Python 1.6)
+
+(4)
+ requires external utilities: :program:`tar` and possibly one of :program:`gzip`,
+ :program:`bzip2`, or :program:`compress`
+
+
+.. _manifest:
+
+Specifying the files to distribute
+==================================
+
+If you don't supply an explicit list of files (or instructions on how to
+generate one), the :command:`sdist` command puts a minimal default set into the
+source distribution:
+
+* all Python source files implied by the :option:`py_modules` and
+ :option:`packages` options
+
+* all C source files mentioned in the :option:`ext_modules` or
+ :option:`libraries` options (
+
+ **\*\*** getting C library sources currently broken---no
+ :meth:`get_source_files` method in :file:`build_clib.py`! **\*\***)
+
+* scripts identified by the :option:`scripts` option
+
+* anything that looks like a test script: :file:`test/test\*.py` (currently, the
+ Distutils don't do anything with test scripts except include them in source
+ distributions, but in the future there will be a standard for testing Python
+ module distributions)
+
+* :file:`README.txt` (or :file:`README`), :file:`setup.py` (or whatever you
+ called your setup script), and :file:`setup.cfg`
+
+Sometimes this is enough, but usually you will want to specify additional files
+to distribute. The typical way to do this is to write a *manifest template*,
+called :file:`MANIFEST.in` by default. The manifest template is just a list of
+instructions for how to generate your manifest file, :file:`MANIFEST`, which is
+the exact list of files to include in your source distribution. The
+:command:`sdist` command processes this template and generates a manifest based
+on its instructions and what it finds in the filesystem.
+
+If you prefer to roll your own manifest file, the format is simple: one filename
+per line, regular files (or symlinks to them) only. If you do supply your own
+:file:`MANIFEST`, you must specify everything: the default set of files
+described above does not apply in this case.
+
+The manifest template has one command per line, where each command specifies a
+set of files to include or exclude from the source distribution. For an
+example, again we turn to the Distutils' own manifest template::
+
+ include *.txt
+ recursive-include examples *.txt *.py
+ prune examples/sample?/build
+
+The meanings should be fairly clear: include all files in the distribution root
+matching :file:`\*.txt`, all files anywhere under the :file:`examples` directory
+matching :file:`\*.txt` or :file:`\*.py`, and exclude all directories matching
+:file:`examples/sample?/build`. All of this is done *after* the standard
+include set, so you can exclude files from the standard set with explicit
+instructions in the manifest template. (Or, you can use the
+:option:`--no-defaults` option to disable the standard set entirely.) There are
+several other commands available in the manifest template mini-language; see
+section :ref:`sdist-cmd`.
+
+The order of commands in the manifest template matters: initially, we have the
+list of default files as described above, and each command in the template adds
+to or removes from that list of files. Once we have fully processed the
+manifest template, we remove files that should not be included in the source
+distribution:
+
+* all files in the Distutils "build" tree (default :file:`build/`)
+
+* all files in directories named :file:`RCS`, :file:`CVS` or :file:`.svn`
+
+Now we have our complete list of files, which is written to the manifest for
+future reference, and then used to build the source distribution archive(s).
+
+You can disable the default set of included files with the
+:option:`--no-defaults` option, and you can disable the standard exclude set
+with :option:`--no-prune`.
+
+Following the Distutils' own manifest template, let's trace how the
+:command:`sdist` command builds the list of files to include in the Distutils
+source distribution:
+
+#. include all Python source files in the :file:`distutils` and
+ :file:`distutils/command` subdirectories (because packages corresponding to
+ those two directories were mentioned in the :option:`packages` option in the
+ setup script---see section :ref:`setup-script`)
+
+#. include :file:`README.txt`, :file:`setup.py`, and :file:`setup.cfg` (standard
+ files)
+
+#. include :file:`test/test\*.py` (standard files)
+
+#. include :file:`\*.txt` in the distribution root (this will find
+ :file:`README.txt` a second time, but such redundancies are weeded out later)
+
+#. include anything matching :file:`\*.txt` or :file:`\*.py` in the sub-tree
+ under :file:`examples`,
+
+#. exclude all files in the sub-trees starting at directories matching
+ :file:`examples/sample?/build`\ ---this may exclude files included by the
+ previous two steps, so it's important that the ``prune`` command in the manifest
+ template comes after the ``recursive-include`` command
+
+#. exclude the entire :file:`build` tree, and any :file:`RCS`, :file:`CVS` and
+ :file:`.svn` directories
+
+Just like in the setup script, file and directory names in the manifest template
+should always be slash-separated; the Distutils will take care of converting
+them to the standard representation on your platform. That way, the manifest
+template is portable across operating systems.
+
+
+.. _manifest-options:
+
+Manifest-related options
+========================
+
+The normal course of operations for the :command:`sdist` command is as follows:
+
+* if the manifest file, :file:`MANIFEST` doesn't exist, read :file:`MANIFEST.in`
+ and create the manifest
+
+* if neither :file:`MANIFEST` nor :file:`MANIFEST.in` exist, create a manifest
+ with just the default file set
+
+* if either :file:`MANIFEST.in` or the setup script (:file:`setup.py`) are more
+ recent than :file:`MANIFEST`, recreate :file:`MANIFEST` by reading
+ :file:`MANIFEST.in`
+
+* use the list of files now in :file:`MANIFEST` (either just generated or read
+ in) to create the source distribution archive(s)
+
+There are a couple of options that modify this behaviour. First, use the
+:option:`--no-defaults` and :option:`--no-prune` to disable the standard
+"include" and "exclude" sets.
+
+Second, you might want to force the manifest to be regenerated---for example, if
+you have added or removed files or directories that match an existing pattern in
+the manifest template, you should regenerate the manifest::
+
+ python setup.py sdist --force-manifest
+
+Or, you might just want to (re)generate the manifest, but not create a source
+distribution::
+
+ python setup.py sdist --manifest-only
+
+:option:`--manifest-only` implies :option:`--force-manifest`. :option:`-o` is a
+shortcut for :option:`--manifest-only`, and :option:`-f` for
+:option:`--force-manifest`.
+
+
diff --git a/Doc/distutils/uploading.rst b/Doc/distutils/uploading.rst
new file mode 100644
index 0000000000..0b82184c48
--- /dev/null
+++ b/Doc/distutils/uploading.rst
@@ -0,0 +1,37 @@
+.. _package-upload:
+
+***************************************
+Uploading Packages to the Package Index
+***************************************
+
+.. versionadded:: 2.5
+
+The Python Package Index (PyPI) not only stores the package info, but also the
+package data if the author of the package wishes to. The distutils command
+:command:`upload` pushes the distribution files to PyPI.
+
+The command is invoked immediately after building one or more distribution
+files. For example, the command ::
+
+ python setup.py sdist bdist_wininst upload
+
+will cause the source distribution and the Windows installer to be uploaded to
+PyPI. Note that these will be uploaded even if they are built using an earlier
+invocation of :file:`setup.py`, but that only distributions named on the command
+line for the invocation including the :command:`upload` command are uploaded.
+
+The :command:`upload` command uses the username, password, and repository URL
+from the :file:`$HOME/.pypirc` file (see section :ref:`pypirc` for more on this
+file).
+
+You can use the :option:`--sign` option to tell :command:`upload` to sign each
+uploaded file using GPG (GNU Privacy Guard). The :program:`gpg` program must
+be available for execution on the system :envvar:`PATH`. You can also specify
+which key to use for signing using the :option:`--identity=*name*` option.
+
+Other :command:`upload` options include :option:`--repository=*url*` (which
+lets you override the repository setting from :file:`$HOME/.pypirc`), and
+:option:`--show-response` (which displays the full response text from the PyPI
+server for help in debugging upload problems).
+
+
diff --git a/Doc/documenting/fromlatex.rst b/Doc/documenting/fromlatex.rst
new file mode 100644
index 0000000000..67abe8a248
--- /dev/null
+++ b/Doc/documenting/fromlatex.rst
@@ -0,0 +1,192 @@
+.. highlightlang:: rest
+
+Differences to the LaTeX markup
+===============================
+
+Though the markup language is different, most of the concepts and markup types
+of the old LaTeX docs have been kept -- environments as reST directives, inline
+commands as reST roles and so forth.
+
+However, there are some differences in the way these work, partly due to the
+differences in the markup languages, partly due to improvements in Sphinx. This
+section lists these differences, in order to give those familiar with the old
+format a quick overview of what they might run into.
+
+Inline markup
+-------------
+
+These changes have been made to inline markup:
+
+* **Cross-reference roles**
+
+ Most of the following semantic roles existed previously as inline commands,
+ but didn't do anything except formatting the content as code. Now, they
+ cross-reference to known targets (some names have also been shortened):
+
+ | *mod* (previously *refmodule* or *module*)
+ | *func* (previously *function*)
+ | *data* (new)
+ | *const*
+ | *class*
+ | *meth* (previously *method*)
+ | *attr* (previously *member*)
+ | *exc* (previously *exception*)
+ | *cdata*
+ | *cfunc* (previously *cfunction*)
+ | *cmacro* (previously *csimplemacro*)
+ | *ctype*
+
+ Also different is the handling of *func* and *meth*: while previously
+ parentheses were added to the callable name (like ``\func{str()}``), they are
+ now appended by the build system -- appending them in the source will result
+ in double parentheses. This also means that ``:func:`str(object)``` will not
+ work as expected -- use ````str(object)```` instead!
+
+* **Inline commands implemented as directives**
+
+ These were inline commands in LaTeX, but are now directives in reST:
+
+ | *deprecated*
+ | *versionadded*
+ | *versionchanged*
+
+ These are used like so::
+
+ .. deprecated:: 2.5
+ Reason of deprecation.
+
+ Also, no period is appended to the text for *versionadded* and
+ *versionchanged*.
+
+ | *note*
+ | *warning*
+
+ These are used like so::
+
+ .. note::
+
+ Content of note.
+
+* **Otherwise changed commands**
+
+ The *samp* command previously formatted code and added quotation marks around
+ it. The *samp* role, however, features a new highlighting system just like
+ *file* does:
+
+ ``:samp:`open({filename}, {mode})``` results in :samp:`open({filename}, {mode})`
+
+* **Dropped commands**
+
+ These were commands in LaTeX, but are not available as roles:
+
+ | *bfcode*
+ | *character* (use :samp:`\`\`'c'\`\``)
+ | *citetitle* (use ```Title <URL>`_``)
+ | *code* (use ````code````)
+ | *email* (just write the address in body text)
+ | *filenq*
+ | *filevar* (use the ``{...}`` highlighting feature of *file*)
+ | *programopt*, *longprogramopt* (use *option*)
+ | *ulink* (use ```Title <URL>`_``)
+ | *url* (just write the URL in body text)
+ | *var* (use ``*var*``)
+ | *infinity*, *plusminus* (use the Unicode character)
+ | *shortversion*, *version* (use the ``|version|`` and ``|release|`` substitutions)
+ | *emph*, *strong* (use the reST markup)
+
+* **Backslash escaping**
+
+ In reST, a backslash must be escaped in normal text, and in the content of
+ roles. However, in code literals and literal blocks, it must not be escaped.
+ Example: ``:file:`C:\\Temp\\my.tmp``` vs. ````open("C:\Temp\my.tmp")````.
+
+
+Information units
+-----------------
+
+Information units (*...desc* environments) have been made reST directives.
+These changes to information units should be noted:
+
+* **New names**
+
+ "desc" has been removed from every name. Additionally, these directives have
+ new names:
+
+ | *cfunction* (previously *cfuncdesc*)
+ | *cmacro* (previously *csimplemacrodesc*)
+ | *exception* (previously *excdesc*)
+ | *function* (previously *funcdesc*)
+ | *attribute* (previously *memberdesc*)
+
+ The *classdesc\** and *excclassdesc* environments have been dropped, the
+ *class* and *exception* directives support classes documented with and without
+ constructor arguments.
+
+* **Multiple objects**
+
+ The equivalent of the *...line* commands is::
+
+ .. function:: do_foo(bar)
+ do_bar(baz)
+
+ Description of the functions.
+
+ IOW, just give one signatures per line, at the same indentation level.
+
+* **Arguments**
+
+ There is no *optional* command. Just give function signatures like they
+ should appear in the output::
+
+ .. function:: open(filename[, mode[, buffering]])
+
+ Description.
+
+ Note: markup in the signature is not supported.
+
+* **Indexing**
+
+ The *...descni* environments have been dropped. To mark an information unit
+ as unsuitable for index entry generation, use the *noindex* option like so::
+
+ .. function:: foo_*
+ :noindex:
+
+ Description.
+
+* **New information unit**
+
+ There is a new generic information unit called "describe" which can be used
+ to document things that are not covered by the other units::
+
+ .. describe:: a == b
+
+ The equals operator.
+
+
+Structure
+---------
+
+The LaTeX docs were split in several toplevel manuals. Now, all files
+are part of the same documentation tree, as indicated by the *toctree*
+directives in the sources. Every *toctree* directive embeds other files
+as subdocuments of the current file (this structure is not necessarily
+mirrored in the filesystem layout). The toplevel file is
+:file:`contents.rst`.
+
+However, most of the old directory structure has been kept, with the
+directories renamed as follows:
+
+* :file:`api` -> :file:`c-api`
+* :file:`dist` -> :file:`distutils`, with the single TeX file split up
+* :file:`doc` -> :file:`documenting`
+* :file:`ext` -> :file:`extending`
+* :file:`inst` -> :file:`installing`
+* :file:`lib` -> :file:`library`
+* :file:`mac` -> merged into :file:`library`, with `mac/using.tex`
+ moved to `howto/pythonmac.rst`
+* :file:`ref` -> :file:`reference`
+* :file:`tut` -> :file:`tutorial`, with the single TeX file split up
+
+
+.. XXX more (index-generating, production lists, ...)
diff --git a/Doc/documenting/index.rst b/Doc/documenting/index.rst
new file mode 100644
index 0000000000..1a3778b092
--- /dev/null
+++ b/Doc/documenting/index.rst
@@ -0,0 +1,33 @@
+.. _documenting-index:
+
+######################
+ Documenting Python
+######################
+
+
+The Python language has a substantial body of documentation, much of it
+contributed by various authors. The markup used for the Python documentation is
+`reStructuredText`_, developed by the `docutils`_ project, amended by custom
+directives and using a toolset named *Sphinx* to postprocess the HTML output.
+
+This document describes the style guide for our documentation, the custom
+reStructuredText markup introduced to support Python documentation and how it
+should be used, as well as the Sphinx build system.
+
+.. _reStructuredText: http://docutils.sf.net/rst.html
+.. _docutils: http://docutils.sf.net/
+
+If you're interested in contributing to Python's documentation, there's no need
+to write reStructuredText if you're not so inclined; plain text contributions
+are more than welcome as well.
+
+.. toctree::
+
+ intro.rst
+ style.rst
+ rest.rst
+ markup.rst
+ sphinx.rst
+
+.. XXX add credits, thanks etc.
+
diff --git a/Doc/documenting/intro.rst b/Doc/documenting/intro.rst
new file mode 100644
index 0000000000..e02ad7de22
--- /dev/null
+++ b/Doc/documenting/intro.rst
@@ -0,0 +1,29 @@
+Introduction
+============
+
+Python's documentation has long been considered to be good for a free
+programming language. There are a number of reasons for this, the most
+important being the early commitment of Python's creator, Guido van Rossum, to
+providing documentation on the language and its libraries, and the continuing
+involvement of the user community in providing assistance for creating and
+maintaining documentation.
+
+The involvement of the community takes many forms, from authoring to bug reports
+to just plain complaining when the documentation could be more complete or
+easier to use.
+
+This document is aimed at authors and potential authors of documentation for
+Python. More specifically, it is for people contributing to the standard
+documentation and developing additional documents using the same tools as the
+standard documents. This guide will be less useful for authors using the Python
+documentation tools for topics other than Python, and less useful still for
+authors not using the tools at all.
+
+If your interest is in contributing to the Python documentation, but you don't
+have the time or inclination to learn reStructuredText and the markup structures
+documented here, there's a welcoming place for you among the Python contributors
+as well. Any time you feel that you can clarify existing documentation or
+provide documentation that's missing, the existing documentation team will
+gladly work with you to integrate your text, dealing with the markup for you.
+Please don't let the material in this document stand between the documentation
+and your desire to help out! \ No newline at end of file
diff --git a/Doc/documenting/markup.rst b/Doc/documenting/markup.rst
new file mode 100644
index 0000000000..831fad9778
--- /dev/null
+++ b/Doc/documenting/markup.rst
@@ -0,0 +1,775 @@
+.. highlightlang:: rest
+
+Additional Markup Constructs
+============================
+
+Sphinx adds a lot of new directives and interpreted text roles to standard reST
+markup. This section contains the reference material for these facilities.
+Documentation for "standard" reST constructs is not included here, though
+they are used in the Python documentation.
+
+File-wide metadata
+------------------
+
+reST has the concept of "field lists"; these are a sequence of fields marked up
+like this::
+
+ :Field name: Field content
+
+A field list at the very top of a file is parsed as the "docinfo", which in
+normal documents can be used to record the author, date of publication and
+other metadata. In Sphinx, the docinfo is used as metadata, too, but not
+displayed in the output.
+
+At the moment, only one metadata field is recognized:
+
+``nocomments``
+ If set, the web application won't display a comment form for a page generated
+ from this source file.
+
+
+Meta-information markup
+-----------------------
+
+.. describe:: sectionauthor
+
+ Identifies the author of the current section. The argument should include
+ the author's name such that it can be used for presentation (though it isn't)
+ and email address. The domain name portion of the address should be lower
+ case. Example::
+
+ .. sectionauthor:: Guido van Rossum <guido@python.org>
+
+ Currently, this markup isn't reflected in the output in any way, but it helps
+ keep track of contributions.
+
+
+Module-specific markup
+----------------------
+
+The markup described in this section is used to provide information about a
+module being documented. Each module should be documented in its own file.
+Normally this markup appears after the title heading of that file; a typical
+file might start like this::
+
+ :mod:`parrot` -- Dead parrot access
+ ===================================
+
+ .. module:: parrot
+ :platform: Unix, Windows
+ :synopsis: Analyze and reanimate dead parrots.
+ .. moduleauthor:: Eric Cleese <eric@python.invalid>
+ .. moduleauthor:: John Idle <john@python.invalid>
+
+As you can see, the module-specific markup consists of two directives, the
+``module`` directive and the ``moduleauthor`` directive.
+
+.. describe:: module
+
+ This directive marks the beginning of the description of a module (or package
+ submodule, in which case the name should be fully qualified, including the
+ package name).
+
+ The ``platform`` option, if present, is a comma-separated list of the
+ platforms on which the module is available (if it is available on all
+ platforms, the option should be omitted). The keys are short identifiers;
+ examples that are in use include "IRIX", "Mac", "Windows", and "Unix". It is
+ important to use a key which has already been used when applicable.
+
+ The ``synopsis`` option should consist of one sentence describing the
+ module's purpose -- it is currently only used in the Global Module Index.
+
+.. describe:: moduleauthor
+
+ The ``moduleauthor`` directive, which can appear multiple times, names the
+ authors of the module code, just like ``sectionauthor`` names the author(s)
+ of a piece of documentation. It too does not result in any output currently.
+
+
+.. note::
+
+ It is important to make the section title of a module-describing file
+ meaningful since that value will be inserted in the table-of-contents trees
+ in overview files.
+
+
+Information units
+-----------------
+
+There are a number of directives used to describe specific features provided by
+modules. Each directive requires one or more signatures to provide basic
+information about what is being described, and the content should be the
+description. The basic version makes entries in the general index; if no index
+entry is desired, you can give the directive option flag ``:noindex:``. The
+following example shows all of the features of this directive type::
+
+ .. function:: spam(eggs)
+ ham(eggs)
+ :noindex:
+
+ Spam or ham the foo.
+
+The signatures of object methods or data attributes should always include the
+type name (``.. method:: FileInput.input(...)``), even if it is obvious from the
+context which type they belong to; this is to enable consistent
+cross-references. If you describe methods belonging to an abstract protocol,
+such as "context managers", include a (pseudo-)type name too to make the
+index entries more informative.
+
+The directives are:
+
+.. describe:: cfunction
+
+ Describes a C function. The signature should be given as in C, e.g.::
+
+ .. cfunction:: PyObject* PyType_GenericAlloc(PyTypeObject *type, Py_ssize_t nitems)
+
+ This is also used to describe function-like preprocessor macros. The names
+ of the arguments should be given so they may be used in the description.
+
+ Note that you don't have to backslash-escape asterisks in the signature,
+ as it is not parsed by the reST inliner.
+
+.. describe:: cmember
+
+ Describes a C struct member. Example signature::
+
+ .. cmember:: PyObject* PyTypeObject.tp_bases
+
+ The text of the description should include the range of values allowed, how
+ the value should be interpreted, and whether the value can be changed.
+ References to structure members in text should use the ``member`` role.
+
+.. describe:: cmacro
+
+ Describes a "simple" C macro. Simple macros are macros which are used
+ for code expansion, but which do not take arguments so cannot be described as
+ functions. This is not to be used for simple constant definitions. Examples
+ of its use in the Python documentation include :cmacro:`PyObject_HEAD` and
+ :cmacro:`Py_BEGIN_ALLOW_THREADS`.
+
+.. describe:: ctype
+
+ Describes a C type. The signature should just be the type name.
+
+.. describe:: cvar
+
+ Describes a global C variable. The signature should include the type, such
+ as::
+
+ .. cvar:: PyObject* PyClass_Type
+
+.. describe:: data
+
+ Describes global data in a module, including both variables and values used
+ as "defined constants." Class and object attributes are not documented
+ using this environment.
+
+.. describe:: exception
+
+ Describes an exception class. The signature can, but need not include
+ parentheses with constructor arguments.
+
+.. describe:: function
+
+ Describes a module-level function. The signature should include the
+ parameters, enclosing optional parameters in brackets. Default values can be
+ given if it enhances clarity. For example::
+
+ .. function:: Timer.repeat([repeat=3[, number=1000000]])
+
+ Object methods are not documented using this directive. Bound object methods
+ placed in the module namespace as part of the public interface of the module
+ are documented using this, as they are equivalent to normal functions for
+ most purposes.
+
+ The description should include information about the parameters required and
+ how they are used (especially whether mutable objects passed as parameters
+ are modified), side effects, and possible exceptions. A small example may be
+ provided.
+
+.. describe:: class
+
+ Describes a class. The signature can include parentheses with parameters
+ which will be shown as the constructor arguments.
+
+.. describe:: attribute
+
+ Describes an object data attribute. The description should include
+ information about the type of the data to be expected and whether it may be
+ changed directly.
+
+.. describe:: method
+
+ Describes an object method. The parameters should not include the ``self``
+ parameter. The description should include similar information to that
+ described for ``function``.
+
+.. describe:: opcode
+
+ Describes a Python bytecode instruction.
+
+
+There is also a generic version of these directives:
+
+.. describe:: describe
+
+ This directive produces the same formatting as the specific ones explained
+ above but does not create index entries or cross-referencing targets. It is
+ used, for example, to describe the directives in this document. Example::
+
+ .. describe:: opcode
+
+ Describes a Python bytecode instruction.
+
+
+Showing code examples
+---------------------
+
+Examples of Python source code or interactive sessions are represented using
+standard reST literal blocks. They are started by a ``::`` at the end of the
+preceding paragraph and delimited by indentation.
+
+Representing an interactive session requires including the prompts and output
+along with the Python code. No special markup is required for interactive
+sessions. After the last line of input or output presented, there should not be
+an "unused" primary prompt; this is an example of what *not* to do::
+
+ >>> 1 + 1
+ 2
+ >>>
+
+Syntax highlighting is handled in a smart way:
+
+* There is a "highlighting language" for each source file. Per default,
+ this is ``'python'`` as the majority of files will have to highlight Python
+ snippets.
+
+* Within Python highlighting mode, interactive sessions are recognized
+ automatically and highlighted appropriately.
+
+* The highlighting language can be changed using the ``highlightlang``
+ directive, used as follows::
+
+ .. highlightlang:: c
+
+ This language is used until the next ``highlightlang`` directive is
+ encountered.
+
+* The valid values for the highlighting language are:
+
+ * ``python`` (the default)
+ * ``c``
+ * ``rest``
+ * ``none`` (no highlighting)
+
+* If highlighting with the current language fails, the block is not highlighted
+ in any way.
+
+Longer displays of verbatim text may be included by storing the example text in
+an external file containing only plain text. The file may be included using the
+``literalinclude`` directive. [1]_ For example, to include the Python source file
+:file:`example.py`, use::
+
+ .. literalinclude:: example.py
+
+The file name is relative to the current file's path. Documentation-specific
+include files should be placed in the ``Doc/includes`` subdirectory.
+
+
+Inline markup
+-------------
+
+As said before, Sphinx uses interpreted text roles to insert semantic markup in
+documents.
+
+Variable names are an exception, they should be marked simply with ``*var*``.
+
+For all other roles, you have to write ``:rolename:`content```.
+
+The following roles refer to objects in modules and are possibly hyperlinked if
+a matching identifier is found:
+
+.. describe:: mod
+
+ The name of a module; a dotted name may be used. This should also be used for
+ package names.
+
+.. describe:: func
+
+ The name of a Python function; dotted names may be used. The role text
+ should include trailing parentheses to enhance readability. The parentheses
+ are stripped when searching for identifiers.
+
+.. describe:: data
+
+ The name of a module-level variable.
+
+.. describe:: const
+
+ The name of a "defined" constant. This may be a C-language ``#define``
+ or a Python variable that is not intended to be changed.
+
+.. describe:: class
+
+ A class name; a dotted name may be used.
+
+.. describe:: meth
+
+ The name of a method of an object. The role text should include the type
+ name, method name and the trailing parentheses. A dotted name may be used.
+
+.. describe:: attr
+
+ The name of a data attribute of an object.
+
+.. describe:: exc
+
+ The name of an exception. A dotted name may be used.
+
+The name enclosed in this markup can include a module name and/or a class name.
+For example, ``:func:`filter``` could refer to a function named ``filter`` in
+the current module, or the built-in function of that name. In contrast,
+``:func:`foo.filter``` clearly refers to the ``filter`` function in the ``foo``
+module.
+
+A similar heuristic is used to determine whether the name is an attribute of
+the currently documented class.
+
+The following roles create cross-references to C-language constructs if they
+are defined in the API documentation:
+
+.. describe:: cdata
+
+ The name of a C-language variable.
+
+.. describe:: cfunc
+
+ The name of a C-language function. Should include trailing parentheses.
+
+.. describe:: cmacro
+
+ The name of a "simple" C macro, as defined above.
+
+.. describe:: ctype
+
+ The name of a C-language type.
+
+
+The following role does possibly create a cross-reference, but does not refer
+to objects:
+
+.. describe:: token
+
+ The name of a grammar token (used in the reference manual to create links
+ between production displays).
+
+---------
+
+The following roles don't do anything special except formatting the text
+in a different style:
+
+.. describe:: command
+
+ The name of an OS-level command, such as ``rm``.
+
+.. describe:: dfn
+
+ Mark the defining instance of a term in the text. (No index entries are
+ generated.)
+
+.. describe:: envvar
+
+ An environment variable. Index entries are generated.
+
+.. describe:: file
+
+ The name of a file or directory. Within the contents, you can use curly
+ braces to indicate a "variable" part, for example::
+
+ ... is installed in :file:`/usr/lib/python2.{x}/site-packages` ...
+
+ In the built documentation, the ``x`` will be displayed differently to
+ indicate that it is to be replaced by the Python minor version.
+
+.. describe:: guilabel
+
+ Labels presented as part of an interactive user interface should be marked
+ using ``guilabel``. This includes labels from text-based interfaces such as
+ those created using :mod:`curses` or other text-based libraries. Any label
+ used in the interface should be marked with this role, including button
+ labels, window titles, field names, menu and menu selection names, and even
+ values in selection lists.
+
+.. describe:: kbd
+
+ Mark a sequence of keystrokes. What form the key sequence takes may depend
+ on platform- or application-specific conventions. When there are no relevant
+ conventions, the names of modifier keys should be spelled out, to improve
+ accessibility for new users and non-native speakers. For example, an
+ *xemacs* key sequence may be marked like ``:kbd:`C-x C-f```, but without
+ reference to a specific application or platform, the same sequence should be
+ marked as ``:kbd:`Control-x Control-f```.
+
+.. describe:: keyword
+
+ The name of a keyword in a programming language.
+
+.. describe:: mailheader
+
+ The name of an RFC 822-style mail header. This markup does not imply that
+ the header is being used in an email message, but can be used to refer to any
+ header of the same "style." This is also used for headers defined by the
+ various MIME specifications. The header name should be entered in the same
+ way it would normally be found in practice, with the camel-casing conventions
+ being preferred where there is more than one common usage. For example:
+ ``:mailheader:`Content-Type```.
+
+.. describe:: makevar
+
+ The name of a :command:`make` variable.
+
+.. describe:: manpage
+
+ A reference to a Unix manual page including the section,
+ e.g. ``:manpage:`ls(1)```.
+
+.. describe:: menuselection
+
+ Menu selections should be marked using the ``menuselection`` role. This is
+ used to mark a complete sequence of menu selections, including selecting
+ submenus and choosing a specific operation, or any subsequence of such a
+ sequence. The names of individual selections should be separated by
+ ``-->``.
+
+ For example, to mark the selection "Start > Programs", use this markup::
+
+ :menuselection:`Start --> Programs`
+
+ When including a selection that includes some trailing indicator, such as the
+ ellipsis some operating systems use to indicate that the command opens a
+ dialog, the indicator should be omitted from the selection name.
+
+.. describe:: mimetype
+
+ The name of a MIME type, or a component of a MIME type (the major or minor
+ portion, taken alone).
+
+.. describe:: newsgroup
+
+ The name of a Usenet newsgroup.
+
+.. describe:: option
+
+ A command-line option to an executable program. The leading hyphen(s) must
+ be included.
+
+.. describe:: program
+
+ The name of an executable program. This may differ from the file name for
+ the executable for some platforms. In particular, the ``.exe`` (or other)
+ extension should be omitted for Windows programs.
+
+.. describe:: regexp
+
+ A regular expression. Quotes should not be included.
+
+.. describe:: samp
+
+ A piece of literal text, such as code. Within the contents, you can use
+ curly braces to indicate a "variable" part, as in ``:file:``.
+
+ If you don't need the "variable part" indication, use the standard
+ ````code```` instead.
+
+.. describe:: var
+
+ A Python or C variable or parameter name.
+
+
+The following roles generate external links:
+
+.. describe:: pep
+
+ A reference to a Python Enhancement Proposal. This generates appropriate
+ index entries. The text "PEP *number*\ " is generated; in the HTML output,
+ this text is a hyperlink to an online copy of the specified PEP.
+
+.. describe:: rfc
+
+ A reference to an Internet Request for Comments. This generates appropriate
+ index entries. The text "RFC *number*\ " is generated; in the HTML output,
+ this text is a hyperlink to an online copy of the specified RFC.
+
+
+Note that there are no special roles for including hyperlinks as you can use
+the standard reST markup for that purpose.
+
+
+.. _doc-ref-role:
+
+Cross-linking markup
+--------------------
+
+To support cross-referencing to arbitrary sections in the documentation, the
+standard reST labels are "abused" a bit: Every label must precede a section
+title; and every label name must be unique throughout the entire documentation
+source.
+
+You can then reference to these sections using the ``:ref:`label-name``` role.
+
+Example::
+
+ .. _my-reference-label:
+
+ Section to cross-reference
+ --------------------------
+
+ This is the text of the section.
+
+ It refers to the section itself, see :ref:`my-reference-label`.
+
+The ``:ref:`` invocation is replaced with the section title.
+
+
+Paragraph-level markup
+----------------------
+
+These directives create short paragraphs and can be used inside information
+units as well as normal text:
+
+.. describe:: note
+
+ An especially important bit of information about an API that a user should be
+ aware of when using whatever bit of API the note pertains to. The content of
+ the directive should be written in complete sentences and include all
+ appropriate punctuation.
+
+ Example::
+
+ .. note::
+
+ This function is not suitable for sending spam e-mails.
+
+.. describe:: warning
+
+ An important bit of information about an API that a user should be very aware
+ of when using whatever bit of API the warning pertains to. The content of
+ the directive should be written in complete sentences and include all
+ appropriate punctuation. This differs from ``note`` in that it is recommended
+ over ``note`` for information regarding security.
+
+.. describe:: versionadded
+
+ This directive documents the version of Python which added the described
+ feature to the library or C API. When this applies to an entire module, it
+ should be placed at the top of the module section before any prose.
+
+ The first argument must be given and is the version in question; you can add
+ a second argument consisting of a *brief* explanation of the change.
+
+ Example::
+
+ .. versionadded:: 2.5
+ The `spam` parameter.
+
+ Note that there must be no blank line between the directive head and the
+ explanation; this is to make these blocks visually continuous in the markup.
+
+.. describe:: versionchanged
+
+ Similar to ``versionadded``, but describes when and what changed in the named
+ feature in some way (new parameters, changed side effects, etc.).
+
+--------------
+
+.. describe:: seealso
+
+ Many sections include a list of references to module documentation or
+ external documents. These lists are created using the ``seealso`` directive.
+
+ The ``seealso`` directive is typically placed in a section just before any
+ sub-sections. For the HTML output, it is shown boxed off from the main flow
+ of the text.
+
+ The content of the ``seealso`` directive should be a reST definition list.
+ Example::
+
+ .. seealso::
+
+ Module :mod:`zipfile`
+ Documentation of the :mod:`zipfile` standard module.
+
+ `GNU tar manual, Basic Tar Format <http://link>`_
+ Documentation for tar archive files, including GNU tar extensions.
+
+.. describe:: rubric
+
+ This directive creates a paragraph heading that is not used to create a
+ table of contents node. It is currently used for the "Footnotes" caption.
+
+.. describe:: centered
+
+ This directive creates a centered boldfaced paragraph. Use it as follows::
+
+ .. centered::
+
+ Paragraph contents.
+
+
+Table-of-contents markup
+------------------------
+
+Since reST does not have facilities to interconnect several documents, or split
+documents into multiple output files, Sphinx uses a custom directive to add
+relations between the single files the documentation is made of, as well as
+tables of contents. The ``toctree`` directive is the central element.
+
+.. describe:: toctree
+
+ This directive inserts a "TOC tree" at the current location, using the
+ individual TOCs (including "sub-TOC trees") of the files given in the
+ directive body. A numeric ``maxdepth`` option may be given to indicate the
+ depth of the tree; by default, all levels are included.
+
+ Consider this example (taken from the library reference index)::
+
+ .. toctree::
+ :maxdepth: 2
+
+ intro.rst
+ strings.rst
+ datatypes.rst
+ numeric.rst
+ (many more files listed here)
+
+ This accomplishes two things:
+
+ * Tables of contents from all those files are inserted, with a maximum depth
+ of two, that means one nested heading. ``toctree`` directives in those
+ files are also taken into account.
+ * Sphinx knows that the relative order of the files ``intro.rst``,
+ ``strings.rst`` and so forth, and it knows that they are children of the
+ shown file, the library index. From this information it generates "next
+ chapter", "previous chapter" and "parent chapter" links.
+
+ In the end, all files included in the build process must occur in one
+ ``toctree`` directive; Sphinx will emit a warning if it finds a file that is
+ not included, because that means that this file will not be reachable through
+ standard navigation.
+
+ The special file ``contents.rst`` at the root of the source directory is the
+ "root" of the TOC tree hierarchy; from it the "Contents" page is generated.
+
+
+Index-generating markup
+-----------------------
+
+Sphinx automatically creates index entries from all information units (like
+functions, classes or attributes) like discussed before.
+
+However, there is also an explicit directive available, to make the index more
+comprehensive and enable index entries in documents where information is not
+mainly contained in information units, such as the language reference.
+
+The directive is ``index`` and contains one or more index entries. Each entry
+consists of a type and a value, separated by a colon.
+
+For example::
+
+ .. index::
+ single: execution!context
+ module: __main__
+ module: sys
+ triple: module; search; path
+
+This directive contains five entries, which will be converted to entries in the
+generated index which link to the exact location of the index statement (or, in
+case of offline media, the corresponding page number).
+
+The possible entry types are:
+
+single
+ Creates a single index entry. Can be made a subentry by separating the
+ subentry text with a semicolon (this is also used below to describe what
+ entries are created).
+pair
+ ``pair: loop; statement`` is a shortcut that creates two index entries,
+ namely ``loop; statement`` and ``statement; loop``.
+triple
+ Likewise, ``triple: module; search; path`` is a shortcut that creates three
+ index entries, which are ``module; search path``, ``search; path, module`` and
+ ``path; module search``.
+module, keyword, operator, object, exception, statement, builtin
+ These all create two index entries. For example, ``module: hashlib`` creates
+ the entries ``module; hashlib`` and ``hashlib; module``.
+
+
+Grammar production displays
+---------------------------
+
+Special markup is available for displaying the productions of a formal grammar.
+The markup is simple and does not attempt to model all aspects of BNF (or any
+derived forms), but provides enough to allow context-free grammars to be
+displayed in a way that causes uses of a symbol to be rendered as hyperlinks to
+the definition of the symbol. There is this directive:
+
+.. describe:: productionlist
+
+ This directive is used to enclose a group of productions. Each production is
+ given on a single line and consists of a name, separated by a colon from the
+ following definition. If the definition spans multiple lines, each
+ continuation line must begin with a colon placed at the same column as in the
+ first line.
+
+ Blank lines are not allowed within ``productionlist`` directive arguments.
+
+ The definition can contain token names which are marked as interpreted text
+ (e.g. ``sum ::= `integer` "+" `integer```) -- this generates cross-references
+ to the productions of these tokens.
+
+ Note that no further reST parsing is done in the production, so that you
+ don't have to escape ``*`` or ``|`` characters.
+
+
+.. XXX describe optional first parameter
+
+The following is an example taken from the Python Reference Manual::
+
+ .. productionlist::
+ try_stmt: try1_stmt | try2_stmt
+ try1_stmt: "try" ":" `suite`
+ : ("except" [`expression` ["," `target`]] ":" `suite`)+
+ : ["else" ":" `suite`]
+ : ["finally" ":" `suite`]
+ try2_stmt: "try" ":" `suite`
+ : "finally" ":" `suite`
+
+
+Substitutions
+-------------
+
+The documentation system provides three substitutions that are defined by default.
+They are set in the build configuration file, see :ref:`doc-build-config`.
+
+.. describe:: |release|
+
+ Replaced by the Python release the documentation refers to. This is the full
+ version string including alpha/beta/release candidate tags, e.g. ``2.5.2b3``.
+
+.. describe:: |version|
+
+ Replaced by the Python version the documentation refers to. This consists
+ only of the major and minor version parts, e.g. ``2.5``, even for version
+ 2.5.1.
+
+.. describe:: |today|
+
+ Replaced by either today's date, or the date set in the build configuration
+ file. Normally has the format ``April 14, 2007``.
+
+
+.. rubric:: Footnotes
+
+.. [1] There is a standard ``.. include`` directive, but it raises errors if the
+ file is not found. This one only emits a warning.
diff --git a/Doc/documenting/rest.rst b/Doc/documenting/rest.rst
new file mode 100644
index 0000000000..8a4fc3dcdf
--- /dev/null
+++ b/Doc/documenting/rest.rst
@@ -0,0 +1,251 @@
+.. highlightlang:: rest
+
+reStructuredText Primer
+=======================
+
+This section is a brief introduction to reStructuredText (reST) concepts and
+syntax, intended to provide authors with enough information to author documents
+productively. Since reST was designed to be a simple, unobtrusive markup
+language, this will not take too long.
+
+.. seealso::
+
+ The authoritative `reStructuredText User
+ Documentation <http://docutils.sourceforge.net/rst.html>`_.
+
+
+Paragraphs
+----------
+
+The paragraph is the most basic block in a reST document. Paragraphs are simply
+chunks of text separated by one or more blank lines. As in Python, indentation
+is significant in reST, so all lines of the same paragraph must be left-aligned
+to the same level of indentation.
+
+
+Inline markup
+-------------
+
+The standard reST inline markup is quite simple: use
+
+* one asterisk: ``*text*`` for emphasis (italics),
+* two asterisks: ``**text**`` for strong emphasis (boldface), and
+* backquotes: ````text```` for code samples.
+
+If asterisks or backquotes appear in running text and could be confused with
+inline markup delimiters, they have to be escaped with a backslash.
+
+Be aware of some restrictions of this markup:
+
+* it may not be nested,
+* content may not start or end with whitespace: ``* text*`` is wrong,
+* it must be separated from surrounding text by non-word characters. Use a
+ backslash escaped space to work around that: ``thisis\ *one*\ word``.
+
+These restrictions may be lifted in future versions of the docutils.
+
+reST also allows for custom "interpreted text roles"', which signify that the
+enclosed text should be interpreted in a specific way. Sphinx uses this to
+provide semantic markup and cross-referencing of identifiers, as described in
+the appropriate section. The general syntax is ``:rolename:`content```.
+
+
+Lists and Quotes
+----------------
+
+List markup is natural: just place an asterisk at the start of a paragraph and
+indent properly. The same goes for numbered lists; they can also be
+autonumbered using a ``#`` sign::
+
+ * This is a bulleted list.
+ * It has two items, the second
+ item uses two lines.
+
+ 1. This is a numbered list.
+ 2. It has two items too.
+
+ #. This is a numbered list.
+ #. It has two items too.
+
+Note that Sphinx disables the use of enumerated lists introduced by alphabetic
+or roman numerals, such as ::
+
+ A. First item
+ B. Second item
+
+
+Nested lists are possible, but be aware that they must be separated from the
+parent list items by blank lines::
+
+ * this is
+ * a list
+
+ * with a nested list
+ * and some subitems
+
+ * and here the parent list continues
+
+Definition lists are created as follows::
+
+ term (up to a line of text)
+ Definition of the term, which must be indented
+
+ and can even consist of multiple paragraphs
+
+ next term
+ Description.
+
+
+Paragraphs are quoted by just indenting them more than the surrounding
+paragraphs.
+
+
+Source Code
+-----------
+
+Literal code blocks are introduced by ending a paragraph with the special marker
+``::``. The literal block must be indented, to be able to include blank lines::
+
+ This is a normal text paragraph. The next paragraph is a code sample::
+
+ It is not processed in any way, except
+ that the indentation is removed.
+
+ It can span multiple lines.
+
+ This is a normal text paragraph again.
+
+The handling of the ``::`` marker is smart:
+
+* If it occurs as a paragraph of its own, that paragraph is completely left
+ out of the document.
+* If it is preceded by whitespace, the marker is removed.
+* If it is preceded by non-whitespace, the marker is replaced by a single
+ colon.
+
+That way, the second sentence in the above example's first paragraph would be
+rendered as "The next paragraph is a code sample:".
+
+
+Hyperlinks
+----------
+
+External links
+^^^^^^^^^^^^^^
+
+Use ```Link text <http://target>`_`` for inline web links. If the link text
+should be the web address, you don't need special markup at all, the parser
+finds links and mail addresses in ordinary text.
+
+Internal links
+^^^^^^^^^^^^^^
+
+Internal linking is done via a special reST role, see the section on specific
+markup, :ref:`doc-ref-role`.
+
+
+Sections
+--------
+
+Section headers are created by underlining (and optionally overlining) the
+section title with a punctuation character, at least as long as the text::
+
+ =================
+ This is a heading
+ =================
+
+Normally, there are no heading levels assigned to certain characters as the
+structure is determined from the succession of headings. However, for the
+Python documentation, we use this convention:
+
+* ``#`` with overline, for parts
+* ``*`` with overline, for chapters
+* ``=``, for sections
+* ``-``, for subsections
+* ``^``, for subsubsections
+* ``"``, for paragraphs
+
+
+Explicit Markup
+---------------
+
+"Explicit markup" is used in reST for most constructs that need special
+handling, such as footnotes, specially-highlighted paragraphs, comments, and
+generic directives.
+
+An explicit markup block begins with a line starting with ``..`` followed by
+whitespace and is terminated by the next paragraph at the same level of
+indentation. (There needs to be a blank line between explicit markup and normal
+paragraphs. This may all sound a bit complicated, but it is intuitive enough
+when you write it.)
+
+
+Directives
+----------
+
+A directive is a generic block of explicit markup. Besides roles, it is one of
+the extension mechanisms of reST, and Sphinx makes heavy use of it.
+
+Basically, a directive consists of a name, arguments, options and content. (Keep
+this terminology in mind, it is used in the next chapter describing custom
+directives.) Looking at this example, ::
+
+ .. function:: foo(x)
+ foo(y, z)
+ :bar: no
+
+ Return a line of text input from the user.
+
+``function`` is the directive name. It is given two arguments here, the
+remainder of the first line and the second line, as well as one option ``bar``
+(as you can see, options are given in the lines immediately following the
+arguments and indicated by the colons).
+
+The directive content follows after a blank line and is indented relative to the
+directive start.
+
+
+Footnotes
+---------
+
+For footnotes, use ``[#]_`` to mark the footnote location, and add the footnote
+body at the bottom of the document after a "Footnotes" rubric heading, like so::
+
+ Lorem ipsum [#]_ dolor sit amet ... [#]_
+
+ .. rubric:: Footnotes
+
+ .. [#] Text of the first footnote.
+ .. [#] Text of the second footnote.
+
+You can also explicitly number the footnotes for better context.
+
+
+Comments
+--------
+
+Every explicit markup block which isn't a valid markup construct (like the
+footnotes above) is regarded as a comment.
+
+
+Source encoding
+---------------
+
+Since the easiest way to include special characters like em dashes or copyright
+signs in reST is to directly write them as Unicode characters, one has to
+specify an encoding:
+
+All Python documentation source files must be in UTF-8 encoding, and the HTML
+documents written from them will be in that encoding as well.
+
+
+Gotchas
+-------
+
+There are some problems one commonly runs into while authoring reST documents:
+
+* **Separation of inline markup:** As said above, inline markup spans must be
+ separated from the surrounding text by non-word characters, you have to use
+ an escaped space to get around that.
+
+.. XXX more?
diff --git a/Doc/documenting/sphinx.rst b/Doc/documenting/sphinx.rst
new file mode 100644
index 0000000000..85e8b5e326
--- /dev/null
+++ b/Doc/documenting/sphinx.rst
@@ -0,0 +1,60 @@
+.. highlightlang:: rest
+
+The Sphinx build system
+=======================
+
+.. XXX: intro...
+
+.. _doc-build-config:
+
+The build configuration file
+----------------------------
+
+The documentation root, that is the ``Doc`` subdirectory of the source
+distribution, contains a file named ``conf.py``. This file is called the "build
+configuration file", and it contains several variables that are read and used
+during a build run.
+
+These variables are:
+
+version : string
+ A string that is used as a replacement for the ``|version|`` reST
+ substitution. It should be the Python version the documentation refers to.
+ This consists only of the major and minor version parts, e.g. ``2.5``, even
+ for version 2.5.1.
+
+release : string
+ A string that is used as a replacement for the ``|release|`` reST
+ substitution. It should be the full version string including
+ alpha/beta/release candidate tags, e.g. ``2.5.2b3``.
+
+Both ``release`` and ``version`` can be ``'auto'``, which means that they are
+determined at runtime from the ``Include/patchlevel.h`` file, if a complete
+Python source distribution can be found, or else from the interpreter running
+Sphinx.
+
+today_fmt : string
+ A ``strftime`` format that is used to format a replacement for the
+ ``|today|`` reST substitution.
+
+today : string
+ A string that can contain a date that should be written to the documentation
+ output literally. If this is nonzero, it is used instead of
+ ``strftime(today_fmt)``.
+
+unused_files : list of strings
+ A list of reST filenames that are to be disregarded during building. This
+ could be docs for temporarily disabled modules or documentation that's not
+ yet ready for public consumption.
+
+last_updated_format : string
+ If this is not an empty string, it will be given to ``time.strftime()`` and
+ written to each generated output file after "last updated on:".
+
+use_smartypants : bool
+ If true, use SmartyPants to convert quotes and dashes to the typographically
+ correct entities.
+
+add_function_parentheses : bool
+ If true, ``()`` will be appended to the content of ``:func:``, ``:meth:`` and
+ ``:cfunc:`` cross-references. \ No newline at end of file
diff --git a/Doc/documenting/style.rst b/Doc/documenting/style.rst
new file mode 100644
index 0000000000..5d0ccb7bed
--- /dev/null
+++ b/Doc/documenting/style.rst
@@ -0,0 +1,70 @@
+.. highlightlang:: rest
+
+Style Guide
+===========
+
+The Python documentation should follow the `Apple Publications Style Guide`_
+wherever possible. This particular style guide was selected mostly because it
+seems reasonable and is easy to get online.
+
+Topics which are not covered in the Apple's style guide will be discussed in
+this document.
+
+All reST files use an indentation of 3 spaces. The maximum line length is 80
+characters for normal text, but tables, deeply indented code samples and long
+links may extend beyond that.
+
+Make generous use of blank lines where applicable; they help grouping things
+together.
+
+A sentence-ending period may be followed by one or two spaces; while reST
+ignores the second space, it is customarily put in by some users, for example
+to aid Emacs' auto-fill mode.
+
+Footnotes are generally discouraged, though they may be used when they are the
+best way to present specific information. When a footnote reference is added at
+the end of the sentence, it should follow the sentence-ending punctuation. The
+reST markup should appear something like this::
+
+ This sentence has a footnote reference. [#]_ This is the next sentence.
+
+Footnotes should be gathered at the end of a file, or if the file is very long,
+at the end of a section. The docutils will automatically create backlinks to
+the footnote reference.
+
+Footnotes may appear in the middle of sentences where appropriate.
+
+Many special names are used in the Python documentation, including the names of
+operating systems, programming languages, standards bodies, and the like. Most
+of these entities are not assigned any special markup, but the preferred
+spellings are given here to aid authors in maintaining the consistency of
+presentation in the Python documentation.
+
+Other terms and words deserve special mention as well; these conventions should
+be used to ensure consistency throughout the documentation:
+
+CPU
+ For "central processing unit." Many style guides say this should be spelled
+ out on the first use (and if you must use it, do so!). For the Python
+ documentation, this abbreviation should be avoided since there's no
+ reasonable way to predict which occurrence will be the first seen by the
+ reader. It is better to use the word "processor" instead.
+
+POSIX
+ The name assigned to a particular group of standards. This is always
+ uppercase.
+
+Python
+ The name of our favorite programming language is always capitalized.
+
+Unicode
+ The name of a character set and matching encoding. This is always written
+ capitalized.
+
+Unix
+ The name of the operating system developed at AT&T Bell Labs in the early
+ 1970s.
+
+
+.. _Apple Publications Style Guide: http://developer.apple.com/documentation/UserExperience/Conceptual/APStyleGuide/AppleStyleGuide2003.pdf
+
diff --git a/Doc/extending/building.rst b/Doc/extending/building.rst
new file mode 100644
index 0000000000..5e1dec870e
--- /dev/null
+++ b/Doc/extending/building.rst
@@ -0,0 +1,131 @@
+.. highlightlang:: c
+
+
+.. _building:
+
+********************************************
+Building C and C++ Extensions with distutils
+********************************************
+
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+Starting in Python 1.4, Python provides, on Unix, a special make file for
+building make files for building dynamically-linked extensions and custom
+interpreters. Starting with Python 2.0, this mechanism (known as related to
+Makefile.pre.in, and Setup files) is no longer supported. Building custom
+interpreters was rarely used, and extension modules can be built using
+distutils.
+
+Building an extension module using distutils requires that distutils is
+installed on the build machine, which is included in Python 2.x and available
+separately for Python 1.5. Since distutils also supports creation of binary
+packages, users don't necessarily need a compiler and distutils to install the
+extension.
+
+A distutils package contains a driver script, :file:`setup.py`. This is a plain
+Python file, which, in the most simple case, could look like this::
+
+ from distutils.core import setup, Extension
+
+ module1 = Extension('demo',
+ sources = ['demo.c'])
+
+ setup (name = 'PackageName',
+ version = '1.0',
+ description = 'This is a demo package',
+ ext_modules = [module1])
+
+
+With this :file:`setup.py`, and a file :file:`demo.c`, running ::
+
+ python setup.py build
+
+will compile :file:`demo.c`, and produce an extension module named ``demo`` in
+the :file:`build` directory. Depending on the system, the module file will end
+up in a subdirectory :file:`build/lib.system`, and may have a name like
+:file:`demo.so` or :file:`demo.pyd`.
+
+In the :file:`setup.py`, all execution is performed by calling the ``setup``
+function. This takes a variable number of keyword arguments, of which the
+example above uses only a subset. Specifically, the example specifies
+meta-information to build packages, and it specifies the contents of the
+package. Normally, a package will contain of addition modules, like Python
+source modules, documentation, subpackages, etc. Please refer to the distutils
+documentation in :ref:`distutils-index` to learn more about the features of
+distutils; this section explains building extension modules only.
+
+It is common to pre-compute arguments to :func:`setup`, to better structure the
+driver script. In the example above, the\ ``ext_modules`` argument to
+:func:`setup` is a list of extension modules, each of which is an instance of
+the :class:`Extension`. In the example, the instance defines an extension named
+``demo`` which is build by compiling a single source file, :file:`demo.c`.
+
+In many cases, building an extension is more complex, since additional
+preprocessor defines and libraries may be needed. This is demonstrated in the
+example below. ::
+
+ from distutils.core import setup, Extension
+
+ module1 = Extension('demo',
+ define_macros = [('MAJOR_VERSION', '1'),
+ ('MINOR_VERSION', '0')],
+ include_dirs = ['/usr/local/include'],
+ libraries = ['tcl83'],
+ library_dirs = ['/usr/local/lib'],
+ sources = ['demo.c'])
+
+ setup (name = 'PackageName',
+ version = '1.0',
+ description = 'This is a demo package',
+ author = 'Martin v. Loewis',
+ author_email = 'martin@v.loewis.de',
+ url = 'http://www.python.org/doc/current/ext/building.html',
+ long_description = '''
+ This is really just a demo package.
+ ''',
+ ext_modules = [module1])
+
+
+In this example, :func:`setup` is called with additional meta-information, which
+is recommended when distribution packages have to be built. For the extension
+itself, it specifies preprocessor defines, include directories, library
+directories, and libraries. Depending on the compiler, distutils passes this
+information in different ways to the compiler. For example, on Unix, this may
+result in the compilation commands ::
+
+ gcc -DNDEBUG -g -O3 -Wall -Wstrict-prototypes -fPIC -DMAJOR_VERSION=1 -DMINOR_VERSION=0 -I/usr/local/include -I/usr/local/include/python2.2 -c demo.c -o build/temp.linux-i686-2.2/demo.o
+
+ gcc -shared build/temp.linux-i686-2.2/demo.o -L/usr/local/lib -ltcl83 -o build/lib.linux-i686-2.2/demo.so
+
+These lines are for demonstration purposes only; distutils users should trust
+that distutils gets the invocations right.
+
+
+.. _distributing:
+
+Distributing your extension modules
+===================================
+
+When an extension has been successfully build, there are three ways to use it.
+
+End-users will typically want to install the module, they do so by running ::
+
+ python setup.py install
+
+Module maintainers should produce source packages; to do so, they run ::
+
+ python setup.py sdist
+
+In some cases, additional files need to be included in a source distribution;
+this is done through a :file:`MANIFEST.in` file; see the distutils documentation
+for details.
+
+If the source distribution has been build successfully, maintainers can also
+create binary distributions. Depending on the platform, one of the following
+commands can be used to do so. ::
+
+ python setup.py bdist_wininst
+ python setup.py bdist_rpm
+ python setup.py bdist_dumb
+
diff --git a/Doc/extending/embedding.rst b/Doc/extending/embedding.rst
new file mode 100644
index 0000000000..b9a567c43b
--- /dev/null
+++ b/Doc/extending/embedding.rst
@@ -0,0 +1,297 @@
+.. highlightlang:: c
+
+
+.. _embedding:
+
+***************************************
+Embedding Python in Another Application
+***************************************
+
+The previous chapters discussed how to extend Python, that is, how to extend the
+functionality of Python by attaching a library of C functions to it. It is also
+possible to do it the other way around: enrich your C/C++ application by
+embedding Python in it. Embedding provides your application with the ability to
+implement some of the functionality of your application in Python rather than C
+or C++. This can be used for many purposes; one example would be to allow users
+to tailor the application to their needs by writing some scripts in Python. You
+can also use it yourself if some of the functionality can be written in Python
+more easily.
+
+Embedding Python is similar to extending it, but not quite. The difference is
+that when you extend Python, the main program of the application is still the
+Python interpreter, while if you embed Python, the main program may have nothing
+to do with Python --- instead, some parts of the application occasionally call
+the Python interpreter to run some Python code.
+
+So if you are embedding Python, you are providing your own main program. One of
+the things this main program has to do is initialize the Python interpreter. At
+the very least, you have to call the function :cfunc:`Py_Initialize` (on Mac OS,
+call :cfunc:`PyMac_Initialize` instead). There are optional calls to pass
+command line arguments to Python. Then later you can call the interpreter from
+any part of the application.
+
+There are several different ways to call the interpreter: you can pass a string
+containing Python statements to :cfunc:`PyRun_SimpleString`, or you can pass a
+stdio file pointer and a file name (for identification in error messages only)
+to :cfunc:`PyRun_SimpleFile`. You can also call the lower-level operations
+described in the previous chapters to construct and use Python objects.
+
+A simple demo of embedding Python can be found in the directory
+:file:`Demo/embed/` of the source distribution.
+
+
+.. seealso::
+
+ :ref:`c-api-index`
+ The details of Python's C interface are given in this manual. A great deal of
+ necessary information can be found here.
+
+
+.. _high-level-embedding:
+
+Very High Level Embedding
+=========================
+
+The simplest form of embedding Python is the use of the very high level
+interface. This interface is intended to execute a Python script without needing
+to interact with the application directly. This can for example be used to
+perform some operation on a file. ::
+
+ #include <Python.h>
+
+ int
+ main(int argc, char *argv[])
+ {
+ Py_Initialize();
+ PyRun_SimpleString("from time import time,ctime\n"
+ "print 'Today is',ctime(time())\n");
+ Py_Finalize();
+ return 0;
+ }
+
+The above code first initializes the Python interpreter with
+:cfunc:`Py_Initialize`, followed by the execution of a hard-coded Python script
+that print the date and time. Afterwards, the :cfunc:`Py_Finalize` call shuts
+the interpreter down, followed by the end of the program. In a real program,
+you may want to get the Python script from another source, perhaps a text-editor
+routine, a file, or a database. Getting the Python code from a file can better
+be done by using the :cfunc:`PyRun_SimpleFile` function, which saves you the
+trouble of allocating memory space and loading the file contents.
+
+
+.. _lower-level-embedding:
+
+Beyond Very High Level Embedding: An overview
+=============================================
+
+The high level interface gives you the ability to execute arbitrary pieces of
+Python code from your application, but exchanging data values is quite
+cumbersome to say the least. If you want that, you should use lower level calls.
+At the cost of having to write more C code, you can achieve almost anything.
+
+It should be noted that extending Python and embedding Python is quite the same
+activity, despite the different intent. Most topics discussed in the previous
+chapters are still valid. To show this, consider what the extension code from
+Python to C really does:
+
+#. Convert data values from Python to C,
+
+#. Perform a function call to a C routine using the converted values, and
+
+#. Convert the data values from the call from C to Python.
+
+When embedding Python, the interface code does:
+
+#. Convert data values from C to Python,
+
+#. Perform a function call to a Python interface routine using the converted
+ values, and
+
+#. Convert the data values from the call from Python to C.
+
+As you can see, the data conversion steps are simply swapped to accommodate the
+different direction of the cross-language transfer. The only difference is the
+routine that you call between both data conversions. When extending, you call a
+C routine, when embedding, you call a Python routine.
+
+This chapter will not discuss how to convert data from Python to C and vice
+versa. Also, proper use of references and dealing with errors is assumed to be
+understood. Since these aspects do not differ from extending the interpreter,
+you can refer to earlier chapters for the required information.
+
+
+.. _pure-embedding:
+
+Pure Embedding
+==============
+
+The first program aims to execute a function in a Python script. Like in the
+section about the very high level interface, the Python interpreter does not
+directly interact with the application (but that will change in the next
+section).
+
+The code to run a function defined in a Python script is:
+
+.. literalinclude:: ../includes/run-func.c
+
+
+This code loads a Python script using ``argv[1]``, and calls the function named
+in ``argv[2]``. Its integer arguments are the other values of the ``argv``
+array. If you compile and link this program (let's call the finished executable
+:program:`call`), and use it to execute a Python script, such as::
+
+ def multiply(a,b):
+ print "Will compute", a, "times", b
+ c = 0
+ for i in range(0, a):
+ c = c + b
+ return c
+
+then the result should be::
+
+ $ call multiply multiply 3 2
+ Will compute 3 times 2
+ Result of call: 6
+
+Although the program is quite large for its functionality, most of the code is
+for data conversion between Python and C, and for error reporting. The
+interesting part with respect to embedding Python starts with
+
+.. % $
+
+::
+
+ Py_Initialize();
+ pName = PyString_FromString(argv[1]);
+ /* Error checking of pName left out */
+ pModule = PyImport_Import(pName);
+
+After initializing the interpreter, the script is loaded using
+:cfunc:`PyImport_Import`. This routine needs a Python string as its argument,
+which is constructed using the :cfunc:`PyString_FromString` data conversion
+routine. ::
+
+ pFunc = PyObject_GetAttrString(pModule, argv[2]);
+ /* pFunc is a new reference */
+
+ if (pFunc && PyCallable_Check(pFunc)) {
+ ...
+ }
+ Py_XDECREF(pFunc);
+
+Once the script is loaded, the name we're looking for is retrieved using
+:cfunc:`PyObject_GetAttrString`. If the name exists, and the object returned is
+callable, you can safely assume that it is a function. The program then
+proceeds by constructing a tuple of arguments as normal. The call to the Python
+function is then made with::
+
+ pValue = PyObject_CallObject(pFunc, pArgs);
+
+Upon return of the function, ``pValue`` is either *NULL* or it contains a
+reference to the return value of the function. Be sure to release the reference
+after examining the value.
+
+
+.. _extending-with-embedding:
+
+Extending Embedded Python
+=========================
+
+Until now, the embedded Python interpreter had no access to functionality from
+the application itself. The Python API allows this by extending the embedded
+interpreter. That is, the embedded interpreter gets extended with routines
+provided by the application. While it sounds complex, it is not so bad. Simply
+forget for a while that the application starts the Python interpreter. Instead,
+consider the application to be a set of subroutines, and write some glue code
+that gives Python access to those routines, just like you would write a normal
+Python extension. For example::
+
+ static int numargs=0;
+
+ /* Return the number of arguments of the application command line */
+ static PyObject*
+ emb_numargs(PyObject *self, PyObject *args)
+ {
+ if(!PyArg_ParseTuple(args, ":numargs"))
+ return NULL;
+ return Py_BuildValue("i", numargs);
+ }
+
+ static PyMethodDef EmbMethods[] = {
+ {"numargs", emb_numargs, METH_VARARGS,
+ "Return the number of arguments received by the process."},
+ {NULL, NULL, 0, NULL}
+ };
+
+Insert the above code just above the :cfunc:`main` function. Also, insert the
+following two statements directly after :cfunc:`Py_Initialize`::
+
+ numargs = argc;
+ Py_InitModule("emb", EmbMethods);
+
+These two lines initialize the ``numargs`` variable, and make the
+:func:`emb.numargs` function accessible to the embedded Python interpreter.
+With these extensions, the Python script can do things like ::
+
+ import emb
+ print "Number of arguments", emb.numargs()
+
+In a real application, the methods will expose an API of the application to
+Python.
+
+.. % \section{For the future}
+.. %
+.. % You don't happen to have a nice library to get textual
+.. % equivalents of numeric values do you :-) ?
+.. % Callbacks here ? (I may be using information from that section
+.. % ?!)
+.. % threads
+.. % code examples do not really behave well if errors happen
+.. % (what to watch out for)
+
+
+.. _embeddingincplusplus:
+
+Embedding Python in C++
+=======================
+
+It is also possible to embed Python in a C++ program; precisely how this is done
+will depend on the details of the C++ system used; in general you will need to
+write the main program in C++, and use the C++ compiler to compile and link your
+program. There is no need to recompile Python itself using C++.
+
+
+.. _link-reqs:
+
+Linking Requirements
+====================
+
+While the :program:`configure` script shipped with the Python sources will
+correctly build Python to export the symbols needed by dynamically linked
+extensions, this is not automatically inherited by applications which embed the
+Python library statically, at least on Unix. This is an issue when the
+application is linked to the static runtime library (:file:`libpython.a`) and
+needs to load dynamic extensions (implemented as :file:`.so` files).
+
+The problem is that some entry points are defined by the Python runtime solely
+for extension modules to use. If the embedding application does not use any of
+these entry points, some linkers will not include those entries in the symbol
+table of the finished executable. Some additional options are needed to inform
+the linker not to remove these symbols.
+
+Determining the right options to use for any given platform can be quite
+difficult, but fortunately the Python configuration already has those values.
+To retrieve them from an installed Python interpreter, start an interactive
+interpreter and have a short session like this::
+
+ >>> import distutils.sysconfig
+ >>> distutils.sysconfig.get_config_var('LINKFORSHARED')
+ '-Xlinker -export-dynamic'
+
+.. index:: module: distutils.sysconfig
+
+The contents of the string presented will be the options that should be used.
+If the string is empty, there's no need to add any additional options. The
+:const:`LINKFORSHARED` definition corresponds to the variable of the same name
+in Python's top-level :file:`Makefile`.
+
diff --git a/Doc/extending/extending.rst b/Doc/extending/extending.rst
new file mode 100644
index 0000000000..bf48c497aa
--- /dev/null
+++ b/Doc/extending/extending.rst
@@ -0,0 +1,1273 @@
+.. highlightlang:: c
+
+
+.. _extending-intro:
+
+******************************
+Extending Python with C or C++
+******************************
+
+It is quite easy to add new built-in modules to Python, if you know how to
+program in C. Such :dfn:`extension modules` can do two things that can't be
+done directly in Python: they can implement new built-in object types, and they
+can call C library functions and system calls.
+
+To support extensions, the Python API (Application Programmers Interface)
+defines a set of functions, macros and variables that provide access to most
+aspects of the Python run-time system. The Python API is incorporated in a C
+source file by including the header ``"Python.h"``.
+
+The compilation of an extension module depends on its intended use as well as on
+your system setup; details are given in later chapters.
+
+
+.. _extending-simpleexample:
+
+A Simple Example
+================
+
+Let's create an extension module called ``spam`` (the favorite food of Monty
+Python fans...) and let's say we want to create a Python interface to the C
+library function :cfunc:`system`. [#]_ This function takes a null-terminated
+character string as argument and returns an integer. We want this function to
+be callable from Python as follows::
+
+ >>> import spam
+ >>> status = spam.system("ls -l")
+
+Begin by creating a file :file:`spammodule.c`. (Historically, if a module is
+called ``spam``, the C file containing its implementation is called
+:file:`spammodule.c`; if the module name is very long, like ``spammify``, the
+module name can be just :file:`spammify.c`.)
+
+The first line of our file can be::
+
+ #include <Python.h>
+
+which pulls in the Python API (you can add a comment describing the purpose of
+the module and a copyright notice if you like).
+
+.. warning::
+
+ Since Python may define some pre-processor definitions which affect the standard
+ headers on some systems, you *must* include :file:`Python.h` before any standard
+ headers are included.
+
+All user-visible symbols defined by :file:`Python.h` have a prefix of ``Py`` or
+``PY``, except those defined in standard header files. For convenience, and
+since they are used extensively by the Python interpreter, ``"Python.h"``
+includes a few standard header files: ``<stdio.h>``, ``<string.h>``,
+``<errno.h>``, and ``<stdlib.h>``. If the latter header file does not exist on
+your system, it declares the functions :cfunc:`malloc`, :cfunc:`free` and
+:cfunc:`realloc` directly.
+
+The next thing we add to our module file is the C function that will be called
+when the Python expression ``spam.system(string)`` is evaluated (we'll see
+shortly how it ends up being called)::
+
+ static PyObject *
+ spam_system(PyObject *self, PyObject *args)
+ {
+ const char *command;
+ int sts;
+
+ if (!PyArg_ParseTuple(args, "s", &command))
+ return NULL;
+ sts = system(command);
+ return Py_BuildValue("i", sts);
+ }
+
+There is a straightforward translation from the argument list in Python (for
+example, the single expression ``"ls -l"``) to the arguments passed to the C
+function. The C function always has two arguments, conventionally named *self*
+and *args*.
+
+The *self* argument is only used when the C function implements a built-in
+method, not a function. In the example, *self* will always be a *NULL* pointer,
+since we are defining a function, not a method. (This is done so that the
+interpreter doesn't have to understand two different types of C functions.)
+
+The *args* argument will be a pointer to a Python tuple object containing the
+arguments. Each item of the tuple corresponds to an argument in the call's
+argument list. The arguments are Python objects --- in order to do anything
+with them in our C function we have to convert them to C values. The function
+:cfunc:`PyArg_ParseTuple` in the Python API checks the argument types and
+converts them to C values. It uses a template string to determine the required
+types of the arguments as well as the types of the C variables into which to
+store the converted values. More about this later.
+
+:cfunc:`PyArg_ParseTuple` returns true (nonzero) if all arguments have the right
+type and its components have been stored in the variables whose addresses are
+passed. It returns false (zero) if an invalid argument list was passed. In the
+latter case it also raises an appropriate exception so the calling function can
+return *NULL* immediately (as we saw in the example).
+
+
+.. _extending-errors:
+
+Intermezzo: Errors and Exceptions
+=================================
+
+An important convention throughout the Python interpreter is the following: when
+a function fails, it should set an exception condition and return an error value
+(usually a *NULL* pointer). Exceptions are stored in a static global variable
+inside the interpreter; if this variable is *NULL* no exception has occurred. A
+second global variable stores the "associated value" of the exception (the
+second argument to :keyword:`raise`). A third variable contains the stack
+traceback in case the error originated in Python code. These three variables
+are the C equivalents of the result in Python of :meth:`sys.exc_info` (see the
+section on module :mod:`sys` in the Python Library Reference). It is important
+to know about them to understand how errors are passed around.
+
+The Python API defines a number of functions to set various types of exceptions.
+
+The most common one is :cfunc:`PyErr_SetString`. Its arguments are an exception
+object and a C string. The exception object is usually a predefined object like
+:cdata:`PyExc_ZeroDivisionError`. The C string indicates the cause of the error
+and is converted to a Python string object and stored as the "associated value"
+of the exception.
+
+Another useful function is :cfunc:`PyErr_SetFromErrno`, which only takes an
+exception argument and constructs the associated value by inspection of the
+global variable :cdata:`errno`. The most general function is
+:cfunc:`PyErr_SetObject`, which takes two object arguments, the exception and
+its associated value. You don't need to :cfunc:`Py_INCREF` the objects passed
+to any of these functions.
+
+You can test non-destructively whether an exception has been set with
+:cfunc:`PyErr_Occurred`. This returns the current exception object, or *NULL*
+if no exception has occurred. You normally don't need to call
+:cfunc:`PyErr_Occurred` to see whether an error occurred in a function call,
+since you should be able to tell from the return value.
+
+When a function *f* that calls another function *g* detects that the latter
+fails, *f* should itself return an error value (usually *NULL* or ``-1``). It
+should *not* call one of the :cfunc:`PyErr_\*` functions --- one has already
+been called by *g*. *f*'s caller is then supposed to also return an error
+indication to *its* caller, again *without* calling :cfunc:`PyErr_\*`, and so on
+--- the most detailed cause of the error was already reported by the function
+that first detected it. Once the error reaches the Python interpreter's main
+loop, this aborts the currently executing Python code and tries to find an
+exception handler specified by the Python programmer.
+
+(There are situations where a module can actually give a more detailed error
+message by calling another :cfunc:`PyErr_\*` function, and in such cases it is
+fine to do so. As a general rule, however, this is not necessary, and can cause
+information about the cause of the error to be lost: most operations can fail
+for a variety of reasons.)
+
+To ignore an exception set by a function call that failed, the exception
+condition must be cleared explicitly by calling :cfunc:`PyErr_Clear`. The only
+time C code should call :cfunc:`PyErr_Clear` is if it doesn't want to pass the
+error on to the interpreter but wants to handle it completely by itself
+(possibly by trying something else, or pretending nothing went wrong).
+
+Every failing :cfunc:`malloc` call must be turned into an exception --- the
+direct caller of :cfunc:`malloc` (or :cfunc:`realloc`) must call
+:cfunc:`PyErr_NoMemory` and return a failure indicator itself. All the
+object-creating functions (for example, :cfunc:`PyInt_FromLong`) already do
+this, so this note is only relevant to those who call :cfunc:`malloc` directly.
+
+Also note that, with the important exception of :cfunc:`PyArg_ParseTuple` and
+friends, functions that return an integer status usually return a positive value
+or zero for success and ``-1`` for failure, like Unix system calls.
+
+Finally, be careful to clean up garbage (by making :cfunc:`Py_XDECREF` or
+:cfunc:`Py_DECREF` calls for objects you have already created) when you return
+an error indicator!
+
+The choice of which exception to raise is entirely yours. There are predeclared
+C objects corresponding to all built-in Python exceptions, such as
+:cdata:`PyExc_ZeroDivisionError`, which you can use directly. Of course, you
+should choose exceptions wisely --- don't use :cdata:`PyExc_TypeError` to mean
+that a file couldn't be opened (that should probably be :cdata:`PyExc_IOError`).
+If something's wrong with the argument list, the :cfunc:`PyArg_ParseTuple`
+function usually raises :cdata:`PyExc_TypeError`. If you have an argument whose
+value must be in a particular range or must satisfy other conditions,
+:cdata:`PyExc_ValueError` is appropriate.
+
+You can also define a new exception that is unique to your module. For this, you
+usually declare a static object variable at the beginning of your file::
+
+ static PyObject *SpamError;
+
+and initialize it in your module's initialization function (:cfunc:`initspam`)
+with an exception object (leaving out the error checking for now)::
+
+ PyMODINIT_FUNC
+ initspam(void)
+ {
+ PyObject *m;
+
+ m = Py_InitModule("spam", SpamMethods);
+ if (m == NULL)
+ return;
+
+ SpamError = PyErr_NewException("spam.error", NULL, NULL);
+ Py_INCREF(SpamError);
+ PyModule_AddObject(m, "error", SpamError);
+ }
+
+Note that the Python name for the exception object is :exc:`spam.error`. The
+:cfunc:`PyErr_NewException` function may create a class with the base class
+being :exc:`Exception` (unless another class is passed in instead of *NULL*),
+described in :ref:`bltin-exceptions`.
+
+Note also that the :cdata:`SpamError` variable retains a reference to the newly
+created exception class; this is intentional! Since the exception could be
+removed from the module by external code, an owned reference to the class is
+needed to ensure that it will not be discarded, causing :cdata:`SpamError` to
+become a dangling pointer. Should it become a dangling pointer, C code which
+raises the exception could cause a core dump or other unintended side effects.
+
+We discuss the use of PyMODINIT_FUNC as a function return type later in this
+sample.
+
+
+.. _backtoexample:
+
+Back to the Example
+===================
+
+Going back to our example function, you should now be able to understand this
+statement::
+
+ if (!PyArg_ParseTuple(args, "s", &command))
+ return NULL;
+
+It returns *NULL* (the error indicator for functions returning object pointers)
+if an error is detected in the argument list, relying on the exception set by
+:cfunc:`PyArg_ParseTuple`. Otherwise the string value of the argument has been
+copied to the local variable :cdata:`command`. This is a pointer assignment and
+you are not supposed to modify the string to which it points (so in Standard C,
+the variable :cdata:`command` should properly be declared as ``const char
+*command``).
+
+The next statement is a call to the Unix function :cfunc:`system`, passing it
+the string we just got from :cfunc:`PyArg_ParseTuple`::
+
+ sts = system(command);
+
+Our :func:`spam.system` function must return the value of :cdata:`sts` as a
+Python object. This is done using the function :cfunc:`Py_BuildValue`, which is
+something like the inverse of :cfunc:`PyArg_ParseTuple`: it takes a format
+string and an arbitrary number of C values, and returns a new Python object.
+More info on :cfunc:`Py_BuildValue` is given later. ::
+
+ return Py_BuildValue("i", sts);
+
+In this case, it will return an integer object. (Yes, even integers are objects
+on the heap in Python!)
+
+If you have a C function that returns no useful argument (a function returning
+:ctype:`void`), the corresponding Python function must return ``None``. You
+need this idiom to do so (which is implemented by the :cmacro:`Py_RETURN_NONE`
+macro)::
+
+ Py_INCREF(Py_None);
+ return Py_None;
+
+:cdata:`Py_None` is the C name for the special Python object ``None``. It is a
+genuine Python object rather than a *NULL* pointer, which means "error" in most
+contexts, as we have seen.
+
+
+.. _methodtable:
+
+The Module's Method Table and Initialization Function
+=====================================================
+
+I promised to show how :cfunc:`spam_system` is called from Python programs.
+First, we need to list its name and address in a "method table"::
+
+ static PyMethodDef SpamMethods[] = {
+ ...
+ {"system", spam_system, METH_VARARGS,
+ "Execute a shell command."},
+ ...
+ {NULL, NULL, 0, NULL} /* Sentinel */
+ };
+
+Note the third entry (``METH_VARARGS``). This is a flag telling the interpreter
+the calling convention to be used for the C function. It should normally always
+be ``METH_VARARGS`` or ``METH_VARARGS | METH_KEYWORDS``; a value of ``0`` means
+that an obsolete variant of :cfunc:`PyArg_ParseTuple` is used.
+
+When using only ``METH_VARARGS``, the function should expect the Python-level
+parameters to be passed in as a tuple acceptable for parsing via
+:cfunc:`PyArg_ParseTuple`; more information on this function is provided below.
+
+The :const:`METH_KEYWORDS` bit may be set in the third field if keyword
+arguments should be passed to the function. In this case, the C function should
+accept a third ``PyObject *`` parameter which will be a dictionary of keywords.
+Use :cfunc:`PyArg_ParseTupleAndKeywords` to parse the arguments to such a
+function.
+
+The method table must be passed to the interpreter in the module's
+initialization function. The initialization function must be named
+:cfunc:`initname`, where *name* is the name of the module, and should be the
+only non-\ :keyword:`static` item defined in the module file::
+
+ PyMODINIT_FUNC
+ initspam(void)
+ {
+ (void) Py_InitModule("spam", SpamMethods);
+ }
+
+Note that PyMODINIT_FUNC declares the function as ``void`` return type,
+declares any special linkage declarations required by the platform, and for C++
+declares the function as ``extern "C"``.
+
+When the Python program imports module :mod:`spam` for the first time,
+:cfunc:`initspam` is called. (See below for comments about embedding Python.)
+It calls :cfunc:`Py_InitModule`, which creates a "module object" (which is
+inserted in the dictionary ``sys.modules`` under the key ``"spam"``), and
+inserts built-in function objects into the newly created module based upon the
+table (an array of :ctype:`PyMethodDef` structures) that was passed as its
+second argument. :cfunc:`Py_InitModule` returns a pointer to the module object
+that it creates (which is unused here). It may abort with a fatal error for
+certain errors, or return *NULL* if the module could not be initialized
+satisfactorily.
+
+When embedding Python, the :cfunc:`initspam` function is not called
+automatically unless there's an entry in the :cdata:`_PyImport_Inittab` table.
+The easiest way to handle this is to statically initialize your
+statically-linked modules by directly calling :cfunc:`initspam` after the call
+to :cfunc:`Py_Initialize`::
+
+ int
+ main(int argc, char *argv[])
+ {
+ /* Pass argv[0] to the Python interpreter */
+ Py_SetProgramName(argv[0]);
+
+ /* Initialize the Python interpreter. Required. */
+ Py_Initialize();
+
+ /* Add a static module */
+ initspam();
+
+An example may be found in the file :file:`Demo/embed/demo.c` in the Python
+source distribution.
+
+.. note::
+
+ Removing entries from ``sys.modules`` or importing compiled modules into
+ multiple interpreters within a process (or following a :cfunc:`fork` without an
+ intervening :cfunc:`exec`) can create problems for some extension modules.
+ Extension module authors should exercise caution when initializing internal data
+ structures.
+
+A more substantial example module is included in the Python source distribution
+as :file:`Modules/xxmodule.c`. This file may be used as a template or simply
+read as an example. The :program:`modulator.py` script included in the source
+distribution or Windows install provides a simple graphical user interface for
+declaring the functions and objects which a module should implement, and can
+generate a template which can be filled in. The script lives in the
+:file:`Tools/modulator/` directory; see the :file:`README` file there for more
+information.
+
+
+.. _compilation:
+
+Compilation and Linkage
+=======================
+
+There are two more things to do before you can use your new extension: compiling
+and linking it with the Python system. If you use dynamic loading, the details
+may depend on the style of dynamic loading your system uses; see the chapters
+about building extension modules (chapter :ref:`building`) and additional
+information that pertains only to building on Windows (chapter
+:ref:`building-on-windows`) for more information about this.
+
+If you can't use dynamic loading, or if you want to make your module a permanent
+part of the Python interpreter, you will have to change the configuration setup
+and rebuild the interpreter. Luckily, this is very simple on Unix: just place
+your file (:file:`spammodule.c` for example) in the :file:`Modules/` directory
+of an unpacked source distribution, add a line to the file
+:file:`Modules/Setup.local` describing your file::
+
+ spam spammodule.o
+
+and rebuild the interpreter by running :program:`make` in the toplevel
+directory. You can also run :program:`make` in the :file:`Modules/`
+subdirectory, but then you must first rebuild :file:`Makefile` there by running
+':program:`make` Makefile'. (This is necessary each time you change the
+:file:`Setup` file.)
+
+If your module requires additional libraries to link with, these can be listed
+on the line in the configuration file as well, for instance::
+
+ spam spammodule.o -lX11
+
+
+.. _callingpython:
+
+Calling Python Functions from C
+===============================
+
+So far we have concentrated on making C functions callable from Python. The
+reverse is also useful: calling Python functions from C. This is especially the
+case for libraries that support so-called "callback" functions. If a C
+interface makes use of callbacks, the equivalent Python often needs to provide a
+callback mechanism to the Python programmer; the implementation will require
+calling the Python callback functions from a C callback. Other uses are also
+imaginable.
+
+Fortunately, the Python interpreter is easily called recursively, and there is a
+standard interface to call a Python function. (I won't dwell on how to call the
+Python parser with a particular string as input --- if you're interested, have a
+look at the implementation of the :option:`-c` command line option in
+:file:`Python/pythonmain.c` from the Python source code.)
+
+Calling a Python function is easy. First, the Python program must somehow pass
+you the Python function object. You should provide a function (or some other
+interface) to do this. When this function is called, save a pointer to the
+Python function object (be careful to :cfunc:`Py_INCREF` it!) in a global
+variable --- or wherever you see fit. For example, the following function might
+be part of a module definition::
+
+ static PyObject *my_callback = NULL;
+
+ static PyObject *
+ my_set_callback(PyObject *dummy, PyObject *args)
+ {
+ PyObject *result = NULL;
+ PyObject *temp;
+
+ if (PyArg_ParseTuple(args, "O:set_callback", &temp)) {
+ if (!PyCallable_Check(temp)) {
+ PyErr_SetString(PyExc_TypeError, "parameter must be callable");
+ return NULL;
+ }
+ Py_XINCREF(temp); /* Add a reference to new callback */
+ Py_XDECREF(my_callback); /* Dispose of previous callback */
+ my_callback = temp; /* Remember new callback */
+ /* Boilerplate to return "None" */
+ Py_INCREF(Py_None);
+ result = Py_None;
+ }
+ return result;
+ }
+
+This function must be registered with the interpreter using the
+:const:`METH_VARARGS` flag; this is described in section :ref:`methodtable`. The
+:cfunc:`PyArg_ParseTuple` function and its arguments are documented in section
+:ref:`parsetuple`.
+
+The macros :cfunc:`Py_XINCREF` and :cfunc:`Py_XDECREF` increment/decrement the
+reference count of an object and are safe in the presence of *NULL* pointers
+(but note that *temp* will not be *NULL* in this context). More info on them
+in section :ref:`refcounts`.
+
+.. index:: single: PyEval_CallObject()
+
+Later, when it is time to call the function, you call the C function
+:cfunc:`PyEval_CallObject`. This function has two arguments, both pointers to
+arbitrary Python objects: the Python function, and the argument list. The
+argument list must always be a tuple object, whose length is the number of
+arguments. To call the Python function with no arguments, pass an empty tuple;
+to call it with one argument, pass a singleton tuple. :cfunc:`Py_BuildValue`
+returns a tuple when its format string consists of zero or more format codes
+between parentheses. For example::
+
+ int arg;
+ PyObject *arglist;
+ PyObject *result;
+ ...
+ arg = 123;
+ ...
+ /* Time to call the callback */
+ arglist = Py_BuildValue("(i)", arg);
+ result = PyEval_CallObject(my_callback, arglist);
+ Py_DECREF(arglist);
+
+:cfunc:`PyEval_CallObject` returns a Python object pointer: this is the return
+value of the Python function. :cfunc:`PyEval_CallObject` is
+"reference-count-neutral" with respect to its arguments. In the example a new
+tuple was created to serve as the argument list, which is :cfunc:`Py_DECREF`\
+-ed immediately after the call.
+
+The return value of :cfunc:`PyEval_CallObject` is "new": either it is a brand
+new object, or it is an existing object whose reference count has been
+incremented. So, unless you want to save it in a global variable, you should
+somehow :cfunc:`Py_DECREF` the result, even (especially!) if you are not
+interested in its value.
+
+Before you do this, however, it is important to check that the return value
+isn't *NULL*. If it is, the Python function terminated by raising an exception.
+If the C code that called :cfunc:`PyEval_CallObject` is called from Python, it
+should now return an error indication to its Python caller, so the interpreter
+can print a stack trace, or the calling Python code can handle the exception.
+If this is not possible or desirable, the exception should be cleared by calling
+:cfunc:`PyErr_Clear`. For example::
+
+ if (result == NULL)
+ return NULL; /* Pass error back */
+ ...use result...
+ Py_DECREF(result);
+
+Depending on the desired interface to the Python callback function, you may also
+have to provide an argument list to :cfunc:`PyEval_CallObject`. In some cases
+the argument list is also provided by the Python program, through the same
+interface that specified the callback function. It can then be saved and used
+in the same manner as the function object. In other cases, you may have to
+construct a new tuple to pass as the argument list. The simplest way to do this
+is to call :cfunc:`Py_BuildValue`. For example, if you want to pass an integral
+event code, you might use the following code::
+
+ PyObject *arglist;
+ ...
+ arglist = Py_BuildValue("(l)", eventcode);
+ result = PyEval_CallObject(my_callback, arglist);
+ Py_DECREF(arglist);
+ if (result == NULL)
+ return NULL; /* Pass error back */
+ /* Here maybe use the result */
+ Py_DECREF(result);
+
+Note the placement of ``Py_DECREF(arglist)`` immediately after the call, before
+the error check! Also note that strictly spoken this code is not complete:
+:cfunc:`Py_BuildValue` may run out of memory, and this should be checked.
+
+
+.. _parsetuple:
+
+Extracting Parameters in Extension Functions
+============================================
+
+.. index:: single: PyArg_ParseTuple()
+
+The :cfunc:`PyArg_ParseTuple` function is declared as follows::
+
+ int PyArg_ParseTuple(PyObject *arg, char *format, ...);
+
+The *arg* argument must be a tuple object containing an argument list passed
+from Python to a C function. The *format* argument must be a format string,
+whose syntax is explained in :ref:`arg-parsing` in the Python/C API Reference
+Manual. The remaining arguments must be addresses of variables whose type is
+determined by the format string.
+
+Note that while :cfunc:`PyArg_ParseTuple` checks that the Python arguments have
+the required types, it cannot check the validity of the addresses of C variables
+passed to the call: if you make mistakes there, your code will probably crash or
+at least overwrite random bits in memory. So be careful!
+
+Note that any Python object references which are provided to the caller are
+*borrowed* references; do not decrement their reference count!
+
+Some example calls::
+
+ int ok;
+ int i, j;
+ long k, l;
+ const char *s;
+ int size;
+
+ ok = PyArg_ParseTuple(args, ""); /* No arguments */
+ /* Python call: f() */
+
+::
+
+ ok = PyArg_ParseTuple(args, "s", &s); /* A string */
+ /* Possible Python call: f('whoops!') */
+
+::
+
+ ok = PyArg_ParseTuple(args, "lls", &k, &l, &s); /* Two longs and a string */
+ /* Possible Python call: f(1, 2, 'three') */
+
+::
+
+ ok = PyArg_ParseTuple(args, "(ii)s#", &i, &j, &s, &size);
+ /* A pair of ints and a string, whose size is also returned */
+ /* Possible Python call: f((1, 2), 'three') */
+
+::
+
+ {
+ const char *file;
+ const char *mode = "r";
+ int bufsize = 0;
+ ok = PyArg_ParseTuple(args, "s|si", &file, &mode, &bufsize);
+ /* A string, and optionally another string and an integer */
+ /* Possible Python calls:
+ f('spam')
+ f('spam', 'w')
+ f('spam', 'wb', 100000) */
+ }
+
+::
+
+ {
+ int left, top, right, bottom, h, v;
+ ok = PyArg_ParseTuple(args, "((ii)(ii))(ii)",
+ &left, &top, &right, &bottom, &h, &v);
+ /* A rectangle and a point */
+ /* Possible Python call:
+ f(((0, 0), (400, 300)), (10, 10)) */
+ }
+
+::
+
+ {
+ Py_complex c;
+ ok = PyArg_ParseTuple(args, "D:myfunction", &c);
+ /* a complex, also providing a function name for errors */
+ /* Possible Python call: myfunction(1+2j) */
+ }
+
+
+.. _parsetupleandkeywords:
+
+Keyword Parameters for Extension Functions
+==========================================
+
+.. index:: single: PyArg_ParseTupleAndKeywords()
+
+The :cfunc:`PyArg_ParseTupleAndKeywords` function is declared as follows::
+
+ int PyArg_ParseTupleAndKeywords(PyObject *arg, PyObject *kwdict,
+ char *format, char *kwlist[], ...);
+
+The *arg* and *format* parameters are identical to those of the
+:cfunc:`PyArg_ParseTuple` function. The *kwdict* parameter is the dictionary of
+keywords received as the third parameter from the Python runtime. The *kwlist*
+parameter is a *NULL*-terminated list of strings which identify the parameters;
+the names are matched with the type information from *format* from left to
+right. On success, :cfunc:`PyArg_ParseTupleAndKeywords` returns true, otherwise
+it returns false and raises an appropriate exception.
+
+.. note::
+
+ Nested tuples cannot be parsed when using keyword arguments! Keyword parameters
+ passed in which are not present in the *kwlist* will cause :exc:`TypeError` to
+ be raised.
+
+.. index:: single: Philbrick, Geoff
+
+Here is an example module which uses keywords, based on an example by Geoff
+Philbrick (philbrick@hks.com):
+
+.. %
+
+::
+
+ #include "Python.h"
+
+ static PyObject *
+ keywdarg_parrot(PyObject *self, PyObject *args, PyObject *keywds)
+ {
+ int voltage;
+ char *state = "a stiff";
+ char *action = "voom";
+ char *type = "Norwegian Blue";
+
+ static char *kwlist[] = {"voltage", "state", "action", "type", NULL};
+
+ if (!PyArg_ParseTupleAndKeywords(args, keywds, "i|sss", kwlist,
+ &voltage, &state, &action, &type))
+ return NULL;
+
+ printf("-- This parrot wouldn't %s if you put %i Volts through it.\n",
+ action, voltage);
+ printf("-- Lovely plumage, the %s -- It's %s!\n", type, state);
+
+ Py_INCREF(Py_None);
+
+ return Py_None;
+ }
+
+ static PyMethodDef keywdarg_methods[] = {
+ /* The cast of the function is necessary since PyCFunction values
+ * only take two PyObject* parameters, and keywdarg_parrot() takes
+ * three.
+ */
+ {"parrot", (PyCFunction)keywdarg_parrot, METH_VARARGS | METH_KEYWORDS,
+ "Print a lovely skit to standard output."},
+ {NULL, NULL, 0, NULL} /* sentinel */
+ };
+
+::
+
+ void
+ initkeywdarg(void)
+ {
+ /* Create the module and add the functions */
+ Py_InitModule("keywdarg", keywdarg_methods);
+ }
+
+
+.. _buildvalue:
+
+Building Arbitrary Values
+=========================
+
+This function is the counterpart to :cfunc:`PyArg_ParseTuple`. It is declared
+as follows::
+
+ PyObject *Py_BuildValue(char *format, ...);
+
+It recognizes a set of format units similar to the ones recognized by
+:cfunc:`PyArg_ParseTuple`, but the arguments (which are input to the function,
+not output) must not be pointers, just values. It returns a new Python object,
+suitable for returning from a C function called from Python.
+
+One difference with :cfunc:`PyArg_ParseTuple`: while the latter requires its
+first argument to be a tuple (since Python argument lists are always represented
+as tuples internally), :cfunc:`Py_BuildValue` does not always build a tuple. It
+builds a tuple only if its format string contains two or more format units. If
+the format string is empty, it returns ``None``; if it contains exactly one
+format unit, it returns whatever object is described by that format unit. To
+force it to return a tuple of size 0 or one, parenthesize the format string.
+
+Examples (to the left the call, to the right the resulting Python value)::
+
+ Py_BuildValue("") None
+ Py_BuildValue("i", 123) 123
+ Py_BuildValue("iii", 123, 456, 789) (123, 456, 789)
+ Py_BuildValue("s", "hello") 'hello'
+ Py_BuildValue("y", "hello") b'hello'
+ Py_BuildValue("ss", "hello", "world") ('hello', 'world')
+ Py_BuildValue("s#", "hello", 4) 'hell'
+ Py_BuildValue("y#", "hello", 4) b'hell'
+ Py_BuildValue("()") ()
+ Py_BuildValue("(i)", 123) (123,)
+ Py_BuildValue("(ii)", 123, 456) (123, 456)
+ Py_BuildValue("(i,i)", 123, 456) (123, 456)
+ Py_BuildValue("[i,i]", 123, 456) [123, 456]
+ Py_BuildValue("{s:i,s:i}",
+ "abc", 123, "def", 456) {'abc': 123, 'def': 456}
+ Py_BuildValue("((ii)(ii)) (ii)",
+ 1, 2, 3, 4, 5, 6) (((1, 2), (3, 4)), (5, 6))
+
+
+.. _refcounts:
+
+Reference Counts
+================
+
+In languages like C or C++, the programmer is responsible for dynamic allocation
+and deallocation of memory on the heap. In C, this is done using the functions
+:cfunc:`malloc` and :cfunc:`free`. In C++, the operators :keyword:`new` and
+:keyword:`delete` are used with essentially the same meaning and we'll restrict
+the following discussion to the C case.
+
+Every block of memory allocated with :cfunc:`malloc` should eventually be
+returned to the pool of available memory by exactly one call to :cfunc:`free`.
+It is important to call :cfunc:`free` at the right time. If a block's address
+is forgotten but :cfunc:`free` is not called for it, the memory it occupies
+cannot be reused until the program terminates. This is called a :dfn:`memory
+leak`. On the other hand, if a program calls :cfunc:`free` for a block and then
+continues to use the block, it creates a conflict with re-use of the block
+through another :cfunc:`malloc` call. This is called :dfn:`using freed memory`.
+It has the same bad consequences as referencing uninitialized data --- core
+dumps, wrong results, mysterious crashes.
+
+Common causes of memory leaks are unusual paths through the code. For instance,
+a function may allocate a block of memory, do some calculation, and then free
+the block again. Now a change in the requirements for the function may add a
+test to the calculation that detects an error condition and can return
+prematurely from the function. It's easy to forget to free the allocated memory
+block when taking this premature exit, especially when it is added later to the
+code. Such leaks, once introduced, often go undetected for a long time: the
+error exit is taken only in a small fraction of all calls, and most modern
+machines have plenty of virtual memory, so the leak only becomes apparent in a
+long-running process that uses the leaking function frequently. Therefore, it's
+important to prevent leaks from happening by having a coding convention or
+strategy that minimizes this kind of errors.
+
+Since Python makes heavy use of :cfunc:`malloc` and :cfunc:`free`, it needs a
+strategy to avoid memory leaks as well as the use of freed memory. The chosen
+method is called :dfn:`reference counting`. The principle is simple: every
+object contains a counter, which is incremented when a reference to the object
+is stored somewhere, and which is decremented when a reference to it is deleted.
+When the counter reaches zero, the last reference to the object has been deleted
+and the object is freed.
+
+An alternative strategy is called :dfn:`automatic garbage collection`.
+(Sometimes, reference counting is also referred to as a garbage collection
+strategy, hence my use of "automatic" to distinguish the two.) The big
+advantage of automatic garbage collection is that the user doesn't need to call
+:cfunc:`free` explicitly. (Another claimed advantage is an improvement in speed
+or memory usage --- this is no hard fact however.) The disadvantage is that for
+C, there is no truly portable automatic garbage collector, while reference
+counting can be implemented portably (as long as the functions :cfunc:`malloc`
+and :cfunc:`free` are available --- which the C Standard guarantees). Maybe some
+day a sufficiently portable automatic garbage collector will be available for C.
+Until then, we'll have to live with reference counts.
+
+While Python uses the traditional reference counting implementation, it also
+offers a cycle detector that works to detect reference cycles. This allows
+applications to not worry about creating direct or indirect circular references;
+these are the weakness of garbage collection implemented using only reference
+counting. Reference cycles consist of objects which contain (possibly indirect)
+references to themselves, so that each object in the cycle has a reference count
+which is non-zero. Typical reference counting implementations are not able to
+reclaim the memory belonging to any objects in a reference cycle, or referenced
+from the objects in the cycle, even though there are no further references to
+the cycle itself.
+
+The cycle detector is able to detect garbage cycles and can reclaim them so long
+as there are no finalizers implemented in Python (:meth:`__del__` methods).
+When there are such finalizers, the detector exposes the cycles through the
+:mod:`gc` module (specifically, the
+``garbage`` variable in that module). The :mod:`gc` module also exposes a way
+to run the detector (the :func:`collect` function), as well as configuration
+interfaces and the ability to disable the detector at runtime. The cycle
+detector is considered an optional component; though it is included by default,
+it can be disabled at build time using the :option:`--without-cycle-gc` option
+to the :program:`configure` script on Unix platforms (including Mac OS X) or by
+removing the definition of ``WITH_CYCLE_GC`` in the :file:`pyconfig.h` header on
+other platforms. If the cycle detector is disabled in this way, the :mod:`gc`
+module will not be available.
+
+
+.. _refcountsinpython:
+
+Reference Counting in Python
+----------------------------
+
+There are two macros, ``Py_INCREF(x)`` and ``Py_DECREF(x)``, which handle the
+incrementing and decrementing of the reference count. :cfunc:`Py_DECREF` also
+frees the object when the count reaches zero. For flexibility, it doesn't call
+:cfunc:`free` directly --- rather, it makes a call through a function pointer in
+the object's :dfn:`type object`. For this purpose (and others), every object
+also contains a pointer to its type object.
+
+The big question now remains: when to use ``Py_INCREF(x)`` and ``Py_DECREF(x)``?
+Let's first introduce some terms. Nobody "owns" an object; however, you can
+:dfn:`own a reference` to an object. An object's reference count is now defined
+as the number of owned references to it. The owner of a reference is
+responsible for calling :cfunc:`Py_DECREF` when the reference is no longer
+needed. Ownership of a reference can be transferred. There are three ways to
+dispose of an owned reference: pass it on, store it, or call :cfunc:`Py_DECREF`.
+Forgetting to dispose of an owned reference creates a memory leak.
+
+It is also possible to :dfn:`borrow` [#]_ a reference to an object. The
+borrower of a reference should not call :cfunc:`Py_DECREF`. The borrower must
+not hold on to the object longer than the owner from which it was borrowed.
+Using a borrowed reference after the owner has disposed of it risks using freed
+memory and should be avoided completely. [#]_
+
+The advantage of borrowing over owning a reference is that you don't need to
+take care of disposing of the reference on all possible paths through the code
+--- in other words, with a borrowed reference you don't run the risk of leaking
+when a premature exit is taken. The disadvantage of borrowing over leaking is
+that there are some subtle situations where in seemingly correct code a borrowed
+reference can be used after the owner from which it was borrowed has in fact
+disposed of it.
+
+A borrowed reference can be changed into an owned reference by calling
+:cfunc:`Py_INCREF`. This does not affect the status of the owner from which the
+reference was borrowed --- it creates a new owned reference, and gives full
+owner responsibilities (the new owner must dispose of the reference properly, as
+well as the previous owner).
+
+
+.. _ownershiprules:
+
+Ownership Rules
+---------------
+
+Whenever an object reference is passed into or out of a function, it is part of
+the function's interface specification whether ownership is transferred with the
+reference or not.
+
+Most functions that return a reference to an object pass on ownership with the
+reference. In particular, all functions whose function it is to create a new
+object, such as :cfunc:`PyInt_FromLong` and :cfunc:`Py_BuildValue`, pass
+ownership to the receiver. Even if the object is not actually new, you still
+receive ownership of a new reference to that object. For instance,
+:cfunc:`PyInt_FromLong` maintains a cache of popular values and can return a
+reference to a cached item.
+
+Many functions that extract objects from other objects also transfer ownership
+with the reference, for instance :cfunc:`PyObject_GetAttrString`. The picture
+is less clear, here, however, since a few common routines are exceptions:
+:cfunc:`PyTuple_GetItem`, :cfunc:`PyList_GetItem`, :cfunc:`PyDict_GetItem`, and
+:cfunc:`PyDict_GetItemString` all return references that you borrow from the
+tuple, list or dictionary.
+
+The function :cfunc:`PyImport_AddModule` also returns a borrowed reference, even
+though it may actually create the object it returns: this is possible because an
+owned reference to the object is stored in ``sys.modules``.
+
+When you pass an object reference into another function, in general, the
+function borrows the reference from you --- if it needs to store it, it will use
+:cfunc:`Py_INCREF` to become an independent owner. There are exactly two
+important exceptions to this rule: :cfunc:`PyTuple_SetItem` and
+:cfunc:`PyList_SetItem`. These functions take over ownership of the item passed
+to them --- even if they fail! (Note that :cfunc:`PyDict_SetItem` and friends
+don't take over ownership --- they are "normal.")
+
+When a C function is called from Python, it borrows references to its arguments
+from the caller. The caller owns a reference to the object, so the borrowed
+reference's lifetime is guaranteed until the function returns. Only when such a
+borrowed reference must be stored or passed on, it must be turned into an owned
+reference by calling :cfunc:`Py_INCREF`.
+
+The object reference returned from a C function that is called from Python must
+be an owned reference --- ownership is transferred from the function to its
+caller.
+
+
+.. _thinice:
+
+Thin Ice
+--------
+
+There are a few situations where seemingly harmless use of a borrowed reference
+can lead to problems. These all have to do with implicit invocations of the
+interpreter, which can cause the owner of a reference to dispose of it.
+
+The first and most important case to know about is using :cfunc:`Py_DECREF` on
+an unrelated object while borrowing a reference to a list item. For instance::
+
+ void
+ bug(PyObject *list)
+ {
+ PyObject *item = PyList_GetItem(list, 0);
+
+ PyList_SetItem(list, 1, PyInt_FromLong(0L));
+ PyObject_Print(item, stdout, 0); /* BUG! */
+ }
+
+This function first borrows a reference to ``list[0]``, then replaces
+``list[1]`` with the value ``0``, and finally prints the borrowed reference.
+Looks harmless, right? But it's not!
+
+Let's follow the control flow into :cfunc:`PyList_SetItem`. The list owns
+references to all its items, so when item 1 is replaced, it has to dispose of
+the original item 1. Now let's suppose the original item 1 was an instance of a
+user-defined class, and let's further suppose that the class defined a
+:meth:`__del__` method. If this class instance has a reference count of 1,
+disposing of it will call its :meth:`__del__` method.
+
+Since it is written in Python, the :meth:`__del__` method can execute arbitrary
+Python code. Could it perhaps do something to invalidate the reference to
+``item`` in :cfunc:`bug`? You bet! Assuming that the list passed into
+:cfunc:`bug` is accessible to the :meth:`__del__` method, it could execute a
+statement to the effect of ``del list[0]``, and assuming this was the last
+reference to that object, it would free the memory associated with it, thereby
+invalidating ``item``.
+
+The solution, once you know the source of the problem, is easy: temporarily
+increment the reference count. The correct version of the function reads::
+
+ void
+ no_bug(PyObject *list)
+ {
+ PyObject *item = PyList_GetItem(list, 0);
+
+ Py_INCREF(item);
+ PyList_SetItem(list, 1, PyInt_FromLong(0L));
+ PyObject_Print(item, stdout, 0);
+ Py_DECREF(item);
+ }
+
+This is a true story. An older version of Python contained variants of this bug
+and someone spent a considerable amount of time in a C debugger to figure out
+why his :meth:`__del__` methods would fail...
+
+The second case of problems with a borrowed reference is a variant involving
+threads. Normally, multiple threads in the Python interpreter can't get in each
+other's way, because there is a global lock protecting Python's entire object
+space. However, it is possible to temporarily release this lock using the macro
+:cmacro:`Py_BEGIN_ALLOW_THREADS`, and to re-acquire it using
+:cmacro:`Py_END_ALLOW_THREADS`. This is common around blocking I/O calls, to
+let other threads use the processor while waiting for the I/O to complete.
+Obviously, the following function has the same problem as the previous one::
+
+ void
+ bug(PyObject *list)
+ {
+ PyObject *item = PyList_GetItem(list, 0);
+ Py_BEGIN_ALLOW_THREADS
+ ...some blocking I/O call...
+ Py_END_ALLOW_THREADS
+ PyObject_Print(item, stdout, 0); /* BUG! */
+ }
+
+
+.. _nullpointers:
+
+NULL Pointers
+-------------
+
+In general, functions that take object references as arguments do not expect you
+to pass them *NULL* pointers, and will dump core (or cause later core dumps) if
+you do so. Functions that return object references generally return *NULL* only
+to indicate that an exception occurred. The reason for not testing for *NULL*
+arguments is that functions often pass the objects they receive on to other
+function --- if each function were to test for *NULL*, there would be a lot of
+redundant tests and the code would run more slowly.
+
+It is better to test for *NULL* only at the "source:" when a pointer that may be
+*NULL* is received, for example, from :cfunc:`malloc` or from a function that
+may raise an exception.
+
+The macros :cfunc:`Py_INCREF` and :cfunc:`Py_DECREF` do not check for *NULL*
+pointers --- however, their variants :cfunc:`Py_XINCREF` and :cfunc:`Py_XDECREF`
+do.
+
+The macros for checking for a particular object type (``Pytype_Check()``) don't
+check for *NULL* pointers --- again, there is much code that calls several of
+these in a row to test an object against various different expected types, and
+this would generate redundant tests. There are no variants with *NULL*
+checking.
+
+The C function calling mechanism guarantees that the argument list passed to C
+functions (``args`` in the examples) is never *NULL* --- in fact it guarantees
+that it is always a tuple. [#]_
+
+It is a severe error to ever let a *NULL* pointer "escape" to the Python user.
+
+.. % Frank Stajano:
+.. % A pedagogically buggy example, along the lines of the previous listing,
+.. % would be helpful here -- showing in more concrete terms what sort of
+.. % actions could cause the problem. I can't very well imagine it from the
+.. % description.
+
+
+.. _cplusplus:
+
+Writing Extensions in C++
+=========================
+
+It is possible to write extension modules in C++. Some restrictions apply. If
+the main program (the Python interpreter) is compiled and linked by the C
+compiler, global or static objects with constructors cannot be used. This is
+not a problem if the main program is linked by the C++ compiler. Functions that
+will be called by the Python interpreter (in particular, module initialization
+functions) have to be declared using ``extern "C"``. It is unnecessary to
+enclose the Python header files in ``extern "C" {...}`` --- they use this form
+already if the symbol ``__cplusplus`` is defined (all recent C++ compilers
+define this symbol).
+
+
+.. _using-cobjects:
+
+Providing a C API for an Extension Module
+=========================================
+
+.. sectionauthor:: Konrad Hinsen <hinsen@cnrs-orleans.fr>
+
+
+Many extension modules just provide new functions and types to be used from
+Python, but sometimes the code in an extension module can be useful for other
+extension modules. For example, an extension module could implement a type
+"collection" which works like lists without order. Just like the standard Python
+list type has a C API which permits extension modules to create and manipulate
+lists, this new collection type should have a set of C functions for direct
+manipulation from other extension modules.
+
+At first sight this seems easy: just write the functions (without declaring them
+:keyword:`static`, of course), provide an appropriate header file, and document
+the C API. And in fact this would work if all extension modules were always
+linked statically with the Python interpreter. When modules are used as shared
+libraries, however, the symbols defined in one module may not be visible to
+another module. The details of visibility depend on the operating system; some
+systems use one global namespace for the Python interpreter and all extension
+modules (Windows, for example), whereas others require an explicit list of
+imported symbols at module link time (AIX is one example), or offer a choice of
+different strategies (most Unices). And even if symbols are globally visible,
+the module whose functions one wishes to call might not have been loaded yet!
+
+Portability therefore requires not to make any assumptions about symbol
+visibility. This means that all symbols in extension modules should be declared
+:keyword:`static`, except for the module's initialization function, in order to
+avoid name clashes with other extension modules (as discussed in section
+:ref:`methodtable`). And it means that symbols that *should* be accessible from
+other extension modules must be exported in a different way.
+
+Python provides a special mechanism to pass C-level information (pointers) from
+one extension module to another one: CObjects. A CObject is a Python data type
+which stores a pointer (:ctype:`void \*`). CObjects can only be created and
+accessed via their C API, but they can be passed around like any other Python
+object. In particular, they can be assigned to a name in an extension module's
+namespace. Other extension modules can then import this module, retrieve the
+value of this name, and then retrieve the pointer from the CObject.
+
+There are many ways in which CObjects can be used to export the C API of an
+extension module. Each name could get its own CObject, or all C API pointers
+could be stored in an array whose address is published in a CObject. And the
+various tasks of storing and retrieving the pointers can be distributed in
+different ways between the module providing the code and the client modules.
+
+The following example demonstrates an approach that puts most of the burden on
+the writer of the exporting module, which is appropriate for commonly used
+library modules. It stores all C API pointers (just one in the example!) in an
+array of :ctype:`void` pointers which becomes the value of a CObject. The header
+file corresponding to the module provides a macro that takes care of importing
+the module and retrieving its C API pointers; client modules only have to call
+this macro before accessing the C API.
+
+The exporting module is a modification of the :mod:`spam` module from section
+:ref:`extending-simpleexample`. The function :func:`spam.system` does not call
+the C library function :cfunc:`system` directly, but a function
+:cfunc:`PySpam_System`, which would of course do something more complicated in
+reality (such as adding "spam" to every command). This function
+:cfunc:`PySpam_System` is also exported to other extension modules.
+
+The function :cfunc:`PySpam_System` is a plain C function, declared
+:keyword:`static` like everything else::
+
+ static int
+ PySpam_System(const char *command)
+ {
+ return system(command);
+ }
+
+The function :cfunc:`spam_system` is modified in a trivial way::
+
+ static PyObject *
+ spam_system(PyObject *self, PyObject *args)
+ {
+ const char *command;
+ int sts;
+
+ if (!PyArg_ParseTuple(args, "s", &command))
+ return NULL;
+ sts = PySpam_System(command);
+ return Py_BuildValue("i", sts);
+ }
+
+In the beginning of the module, right after the line ::
+
+ #include "Python.h"
+
+two more lines must be added::
+
+ #define SPAM_MODULE
+ #include "spammodule.h"
+
+The ``#define`` is used to tell the header file that it is being included in the
+exporting module, not a client module. Finally, the module's initialization
+function must take care of initializing the C API pointer array::
+
+ PyMODINIT_FUNC
+ initspam(void)
+ {
+ PyObject *m;
+ static void *PySpam_API[PySpam_API_pointers];
+ PyObject *c_api_object;
+
+ m = Py_InitModule("spam", SpamMethods);
+ if (m == NULL)
+ return;
+
+ /* Initialize the C API pointer array */
+ PySpam_API[PySpam_System_NUM] = (void *)PySpam_System;
+
+ /* Create a CObject containing the API pointer array's address */
+ c_api_object = PyCObject_FromVoidPtr((void *)PySpam_API, NULL);
+
+ if (c_api_object != NULL)
+ PyModule_AddObject(m, "_C_API", c_api_object);
+ }
+
+Note that ``PySpam_API`` is declared :keyword:`static`; otherwise the pointer
+array would disappear when :func:`initspam` terminates!
+
+The bulk of the work is in the header file :file:`spammodule.h`, which looks
+like this::
+
+ #ifndef Py_SPAMMODULE_H
+ #define Py_SPAMMODULE_H
+ #ifdef __cplusplus
+ extern "C" {
+ #endif
+
+ /* Header file for spammodule */
+
+ /* C API functions */
+ #define PySpam_System_NUM 0
+ #define PySpam_System_RETURN int
+ #define PySpam_System_PROTO (const char *command)
+
+ /* Total number of C API pointers */
+ #define PySpam_API_pointers 1
+
+
+ #ifdef SPAM_MODULE
+ /* This section is used when compiling spammodule.c */
+
+ static PySpam_System_RETURN PySpam_System PySpam_System_PROTO;
+
+ #else
+ /* This section is used in modules that use spammodule's API */
+
+ static void **PySpam_API;
+
+ #define PySpam_System \
+ (*(PySpam_System_RETURN (*)PySpam_System_PROTO) PySpam_API[PySpam_System_NUM])
+
+ /* Return -1 and set exception on error, 0 on success. */
+ static int
+ import_spam(void)
+ {
+ PyObject *module = PyImport_ImportModule("spam");
+
+ if (module != NULL) {
+ PyObject *c_api_object = PyObject_GetAttrString(module, "_C_API");
+ if (c_api_object == NULL)
+ return -1;
+ if (PyCObject_Check(c_api_object))
+ PySpam_API = (void **)PyCObject_AsVoidPtr(c_api_object);
+ Py_DECREF(c_api_object);
+ }
+ return 0;
+ }
+
+ #endif
+
+ #ifdef __cplusplus
+ }
+ #endif
+
+ #endif /* !defined(Py_SPAMMODULE_H) */
+
+All that a client module must do in order to have access to the function
+:cfunc:`PySpam_System` is to call the function (or rather macro)
+:cfunc:`import_spam` in its initialization function::
+
+ PyMODINIT_FUNC
+ initclient(void)
+ {
+ PyObject *m;
+
+ m = Py_InitModule("client", ClientMethods);
+ if (m == NULL)
+ return;
+ if (import_spam() < 0)
+ return;
+ /* additional initialization can happen here */
+ }
+
+The main disadvantage of this approach is that the file :file:`spammodule.h` is
+rather complicated. However, the basic structure is the same for each function
+that is exported, so it has to be learned only once.
+
+Finally it should be mentioned that CObjects offer additional functionality,
+which is especially useful for memory allocation and deallocation of the pointer
+stored in a CObject. The details are described in the Python/C API Reference
+Manual in the section :ref:`cobjects` and in the implementation of CObjects (files
+:file:`Include/cobject.h` and :file:`Objects/cobject.c` in the Python source
+code distribution).
+
+.. rubric:: Footnotes
+
+.. [#] An interface for this function already exists in the standard module :mod:`os`
+ --- it was chosen as a simple and straightforward example.
+
+.. [#] The metaphor of "borrowing" a reference is not completely correct: the owner
+ still has a copy of the reference.
+
+.. [#] Checking that the reference count is at least 1 **does not work** --- the
+ reference count itself could be in freed memory and may thus be reused for
+ another object!
+
+.. [#] These guarantees don't hold when you use the "old" style calling convention ---
+ this is still found in much existing code.
+
diff --git a/Doc/extending/index.rst b/Doc/extending/index.rst
new file mode 100644
index 0000000000..6e8cf7906f
--- /dev/null
+++ b/Doc/extending/index.rst
@@ -0,0 +1,34 @@
+.. _extending-index:
+
+##################################################
+ Extending and Embedding the Python Interpreter
+##################################################
+
+:Release: |version|
+:Date: |today|
+
+This document describes how to write modules in C or C++ to extend the Python
+interpreter with new modules. Those modules can define new functions but also
+new object types and their methods. The document also describes how to embed
+the Python interpreter in another application, for use as an extension language.
+Finally, it shows how to compile and link extension modules so that they can be
+loaded dynamically (at run time) into the interpreter, if the underlying
+operating system supports this feature.
+
+This document assumes basic knowledge about Python. For an informal
+introduction to the language, see :ref:`tutorial-index`. :ref:`reference-index`
+gives a more formal definition of the language. :ref:`library-index` documents
+the existing object types, functions and modules (both built-in and written in
+Python) that give the language its wide application range.
+
+For a detailed description of the whole Python/C API, see the separate
+:ref:`c-api-index`.
+
+.. toctree::
+ :maxdepth: 2
+
+ extending.rst
+ newtypes.rst
+ building.rst
+ windows.rst
+ embedding.rst
diff --git a/Doc/extending/newtypes.rst b/Doc/extending/newtypes.rst
new file mode 100644
index 0000000000..72aaf1b8b8
--- /dev/null
+++ b/Doc/extending/newtypes.rst
@@ -0,0 +1,1580 @@
+.. highlightlang:: c
+
+
+.. _defining-new-types:
+
+******************
+Defining New Types
+******************
+
+.. sectionauthor:: Michael Hudson <mwh@python.net>
+.. sectionauthor:: Dave Kuhlman <dkuhlman@rexx.com>
+.. sectionauthor:: Jim Fulton <jim@zope.com>
+
+
+As mentioned in the last chapter, Python allows the writer of an extension
+module to define new types that can be manipulated from Python code, much like
+strings and lists in core Python.
+
+This is not hard; the code for all extension types follows a pattern, but there
+are some details that you need to understand before you can get started.
+
+.. note::
+
+ The way new types are defined changed dramatically (and for the better) in
+ Python 2.2. This document documents how to define new types for Python 2.2 and
+ later. If you need to support older versions of Python, you will need to refer
+ to `older versions of this documentation
+ <http://www.python.org/doc/versions/>`_.
+
+
+.. _dnt-basics:
+
+The Basics
+==========
+
+The Python runtime sees all Python objects as variables of type
+:ctype:`PyObject\*`. A :ctype:`PyObject` is not a very magnificent object - it
+just contains the refcount and a pointer to the object's "type object". This is
+where the action is; the type object determines which (C) functions get called
+when, for instance, an attribute gets looked up on an object or it is multiplied
+by another object. These C functions are called "type methods" to distinguish
+them from things like ``[].append`` (which we call "object methods").
+
+So, if you want to define a new object type, you need to create a new type
+object.
+
+This sort of thing can only be explained by example, so here's a minimal, but
+complete, module that defines a new type:
+
+.. literalinclude:: ../includes/noddy.c
+
+
+Now that's quite a bit to take in at once, but hopefully bits will seem familiar
+from the last chapter.
+
+The first bit that will be new is::
+
+ typedef struct {
+ PyObject_HEAD
+ } noddy_NoddyObject;
+
+This is what a Noddy object will contain---in this case, nothing more than every
+Python object contains, namely a refcount and a pointer to a type object. These
+are the fields the ``PyObject_HEAD`` macro brings in. The reason for the macro
+is to standardize the layout and to enable special debugging fields in debug
+builds. Note that there is no semicolon after the ``PyObject_HEAD`` macro; one
+is included in the macro definition. Be wary of adding one by accident; it's
+easy to do from habit, and your compiler might not complain, but someone else's
+probably will! (On Windows, MSVC is known to call this an error and refuse to
+compile the code.)
+
+For contrast, let's take a look at the corresponding definition for standard
+Python integers::
+
+ typedef struct {
+ PyObject_HEAD
+ long ob_ival;
+ } PyIntObject;
+
+Moving on, we come to the crunch --- the type object. ::
+
+ static PyTypeObject noddy_NoddyType = {
+ PyObject_HEAD_INIT(NULL)
+ 0, /*ob_size*/
+ "noddy.Noddy", /*tp_name*/
+ sizeof(noddy_NoddyObject), /*tp_basicsize*/
+ 0, /*tp_itemsize*/
+ 0, /*tp_dealloc*/
+ 0, /*tp_print*/
+ 0, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+ 0, /*tp_as_number*/
+ 0, /*tp_as_sequence*/
+ 0, /*tp_as_mapping*/
+ 0, /*tp_hash */
+ 0, /*tp_call*/
+ 0, /*tp_str*/
+ 0, /*tp_getattro*/
+ 0, /*tp_setattro*/
+ 0, /*tp_as_buffer*/
+ Py_TPFLAGS_DEFAULT, /*tp_flags*/
+ "Noddy objects", /* tp_doc */
+ };
+
+Now if you go and look up the definition of :ctype:`PyTypeObject` in
+:file:`object.h` you'll see that it has many more fields that the definition
+above. The remaining fields will be filled with zeros by the C compiler, and
+it's common practice to not specify them explicitly unless you need them.
+
+This is so important that we're going to pick the top of it apart still
+further::
+
+ PyObject_HEAD_INIT(NULL)
+
+This line is a bit of a wart; what we'd like to write is::
+
+ PyObject_HEAD_INIT(&PyType_Type)
+
+as the type of a type object is "type", but this isn't strictly conforming C and
+some compilers complain. Fortunately, this member will be filled in for us by
+:cfunc:`PyType_Ready`. ::
+
+ 0, /* ob_size */
+
+The :attr:`ob_size` field of the header is not used; its presence in the type
+structure is a historical artifact that is maintained for binary compatibility
+with extension modules compiled for older versions of Python. Always set this
+field to zero. ::
+
+ "noddy.Noddy", /* tp_name */
+
+The name of our type. This will appear in the default textual representation of
+our objects and in some error messages, for example::
+
+ >>> "" + noddy.new_noddy()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: cannot add type "noddy.Noddy" to string
+
+Note that the name is a dotted name that includes both the module name and the
+name of the type within the module. The module in this case is :mod:`noddy` and
+the type is :class:`Noddy`, so we set the type name to :class:`noddy.Noddy`. ::
+
+ sizeof(noddy_NoddyObject), /* tp_basicsize */
+
+This is so that Python knows how much memory to allocate when you call
+:cfunc:`PyObject_New`.
+
+.. note::
+
+ If you want your type to be subclassable from Python, and your type has the same
+ :attr:`tp_basicsize` as its base type, you may have problems with multiple
+ inheritance. A Python subclass of your type will have to list your type first
+ in its :attr:`__bases__`, or else it will not be able to call your type's
+ :meth:`__new__` method without getting an error. You can avoid this problem by
+ ensuring that your type has a larger value for :attr:`tp_basicsize` than its
+ base type does. Most of the time, this will be true anyway, because either your
+ base type will be :class:`object`, or else you will be adding data members to
+ your base type, and therefore increasing its size.
+
+::
+
+ 0, /* tp_itemsize */
+
+This has to do with variable length objects like lists and strings. Ignore this
+for now.
+
+Skipping a number of type methods that we don't provide, we set the class flags
+to :const:`Py_TPFLAGS_DEFAULT`. ::
+
+ Py_TPFLAGS_DEFAULT, /*tp_flags*/
+
+All types should include this constant in their flags. It enables all of the
+members defined by the current version of Python.
+
+We provide a doc string for the type in :attr:`tp_doc`. ::
+
+ "Noddy objects", /* tp_doc */
+
+Now we get into the type methods, the things that make your objects different
+from the others. We aren't going to implement any of these in this version of
+the module. We'll expand this example later to have more interesting behavior.
+
+For now, all we want to be able to do is to create new :class:`Noddy` objects.
+To enable object creation, we have to provide a :attr:`tp_new` implementation.
+In this case, we can just use the default implementation provided by the API
+function :cfunc:`PyType_GenericNew`. We'd like to just assign this to the
+:attr:`tp_new` slot, but we can't, for portability sake, On some platforms or
+compilers, we can't statically initialize a structure member with a function
+defined in another C module, so, instead, we'll assign the :attr:`tp_new` slot
+in the module initialization function just before calling
+:cfunc:`PyType_Ready`::
+
+ noddy_NoddyType.tp_new = PyType_GenericNew;
+ if (PyType_Ready(&noddy_NoddyType) < 0)
+ return;
+
+All the other type methods are *NULL*, so we'll go over them later --- that's
+for a later section!
+
+Everything else in the file should be familiar, except for some code in
+:cfunc:`initnoddy`::
+
+ if (PyType_Ready(&noddy_NoddyType) < 0)
+ return;
+
+This initializes the :class:`Noddy` type, filing in a number of members,
+including :attr:`ob_type` that we initially set to *NULL*. ::
+
+ PyModule_AddObject(m, "Noddy", (PyObject *)&noddy_NoddyType);
+
+This adds the type to the module dictionary. This allows us to create
+:class:`Noddy` instances by calling the :class:`Noddy` class::
+
+ >>> import noddy
+ >>> mynoddy = noddy.Noddy()
+
+That's it! All that remains is to build it; put the above code in a file called
+:file:`noddy.c` and ::
+
+ from distutils.core import setup, Extension
+ setup(name="noddy", version="1.0",
+ ext_modules=[Extension("noddy", ["noddy.c"])])
+
+in a file called :file:`setup.py`; then typing ::
+
+ $ python setup.py build
+
+at a shell should produce a file :file:`noddy.so` in a subdirectory; move to
+that directory and fire up Python --- you should be able to ``import noddy`` and
+play around with Noddy objects.
+
+.. % $ <-- bow to font-lock ;-(
+
+That wasn't so hard, was it?
+
+Of course, the current Noddy type is pretty uninteresting. It has no data and
+doesn't do anything. It can't even be subclassed.
+
+
+Adding data and methods to the Basic example
+--------------------------------------------
+
+Let's expend the basic example to add some data and methods. Let's also make
+the type usable as a base class. We'll create a new module, :mod:`noddy2` that
+adds these capabilities:
+
+.. literalinclude:: ../includes/noddy2.c
+
+
+This version of the module has a number of changes.
+
+We've added an extra include::
+
+ #include "structmember.h"
+
+This include provides declarations that we use to handle attributes, as
+described a bit later.
+
+The name of the :class:`Noddy` object structure has been shortened to
+:class:`Noddy`. The type object name has been shortened to :class:`NoddyType`.
+
+The :class:`Noddy` type now has three data attributes, *first*, *last*, and
+*number*. The *first* and *last* variables are Python strings containing first
+and last names. The *number* attribute is an integer.
+
+The object structure is updated accordingly::
+
+ typedef struct {
+ PyObject_HEAD
+ PyObject *first;
+ PyObject *last;
+ int number;
+ } Noddy;
+
+Because we now have data to manage, we have to be more careful about object
+allocation and deallocation. At a minimum, we need a deallocation method::
+
+ static void
+ Noddy_dealloc(Noddy* self)
+ {
+ Py_XDECREF(self->first);
+ Py_XDECREF(self->last);
+ self->ob_type->tp_free((PyObject*)self);
+ }
+
+which is assigned to the :attr:`tp_dealloc` member::
+
+ (destructor)Noddy_dealloc, /*tp_dealloc*/
+
+This method decrements the reference counts of the two Python attributes. We use
+:cfunc:`Py_XDECREF` here because the :attr:`first` and :attr:`last` members
+could be *NULL*. It then calls the :attr:`tp_free` member of the object's type
+to free the object's memory. Note that the object's type might not be
+:class:`NoddyType`, because the object may be an instance of a subclass.
+
+We want to make sure that the first and last names are initialized to empty
+strings, so we provide a new method::
+
+ static PyObject *
+ Noddy_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+ {
+ Noddy *self;
+
+ self = (Noddy *)type->tp_alloc(type, 0);
+ if (self != NULL) {
+ self->first = PyString_FromString("");
+ if (self->first == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->last = PyString_FromString("");
+ if (self->last == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->number = 0;
+ }
+
+ return (PyObject *)self;
+ }
+
+and install it in the :attr:`tp_new` member::
+
+ Noddy_new, /* tp_new */
+
+The new member is responsible for creating (as opposed to initializing) objects
+of the type. It is exposed in Python as the :meth:`__new__` method. See the
+paper titled "Unifying types and classes in Python" for a detailed discussion of
+the :meth:`__new__` method. One reason to implement a new method is to assure
+the initial values of instance variables. In this case, we use the new method
+to make sure that the initial values of the members :attr:`first` and
+:attr:`last` are not *NULL*. If we didn't care whether the initial values were
+*NULL*, we could have used :cfunc:`PyType_GenericNew` as our new method, as we
+did before. :cfunc:`PyType_GenericNew` initializes all of the instance variable
+members to *NULL*.
+
+The new method is a static method that is passed the type being instantiated and
+any arguments passed when the type was called, and that returns the new object
+created. New methods always accept positional and keyword arguments, but they
+often ignore the arguments, leaving the argument handling to initializer
+methods. Note that if the type supports subclassing, the type passed may not be
+the type being defined. The new method calls the tp_alloc slot to allocate
+memory. We don't fill the :attr:`tp_alloc` slot ourselves. Rather
+:cfunc:`PyType_Ready` fills it for us by inheriting it from our base class,
+which is :class:`object` by default. Most types use the default allocation.
+
+.. note::
+
+ If you are creating a co-operative :attr:`tp_new` (one that calls a base type's
+ :attr:`tp_new` or :meth:`__new__`), you must *not* try to determine what method
+ to call using method resolution order at runtime. Always statically determine
+ what type you are going to call, and call its :attr:`tp_new` directly, or via
+ ``type->tp_base->tp_new``. If you do not do this, Python subclasses of your
+ type that also inherit from other Python-defined classes may not work correctly.
+ (Specifically, you may not be able to create instances of such subclasses
+ without getting a :exc:`TypeError`.)
+
+We provide an initialization function::
+
+ static int
+ Noddy_init(Noddy *self, PyObject *args, PyObject *kwds)
+ {
+ PyObject *first=NULL, *last=NULL, *tmp;
+
+ static char *kwlist[] = {"first", "last", "number", NULL};
+
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
+ &first, &last,
+ &self->number))
+ return -1;
+
+ if (first) {
+ tmp = self->first;
+ Py_INCREF(first);
+ self->first = first;
+ Py_XDECREF(tmp);
+ }
+
+ if (last) {
+ tmp = self->last;
+ Py_INCREF(last);
+ self->last = last;
+ Py_XDECREF(tmp);
+ }
+
+ return 0;
+ }
+
+by filling the :attr:`tp_init` slot. ::
+
+ (initproc)Noddy_init, /* tp_init */
+
+The :attr:`tp_init` slot is exposed in Python as the :meth:`__init__` method. It
+is used to initialize an object after it's created. Unlike the new method, we
+can't guarantee that the initializer is called. The initializer isn't called
+when unpickling objects and it can be overridden. Our initializer accepts
+arguments to provide initial values for our instance. Initializers always accept
+positional and keyword arguments.
+
+Initializers can be called multiple times. Anyone can call the :meth:`__init__`
+method on our objects. For this reason, we have to be extra careful when
+assigning the new values. We might be tempted, for example to assign the
+:attr:`first` member like this::
+
+ if (first) {
+ Py_XDECREF(self->first);
+ Py_INCREF(first);
+ self->first = first;
+ }
+
+But this would be risky. Our type doesn't restrict the type of the
+:attr:`first` member, so it could be any kind of object. It could have a
+destructor that causes code to be executed that tries to access the
+:attr:`first` member. To be paranoid and protect ourselves against this
+possibility, we almost always reassign members before decrementing their
+reference counts. When don't we have to do this?
+
+* when we absolutely know that the reference count is greater than 1
+
+* when we know that deallocation of the object [#]_ will not cause any calls
+ back into our type's code
+
+* when decrementing a reference count in a :attr:`tp_dealloc` handler when
+ garbage-collections is not supported [#]_
+
+We want to want to expose our instance variables as attributes. There are a
+number of ways to do that. The simplest way is to define member definitions::
+
+ static PyMemberDef Noddy_members[] = {
+ {"first", T_OBJECT_EX, offsetof(Noddy, first), 0,
+ "first name"},
+ {"last", T_OBJECT_EX, offsetof(Noddy, last), 0,
+ "last name"},
+ {"number", T_INT, offsetof(Noddy, number), 0,
+ "noddy number"},
+ {NULL} /* Sentinel */
+ };
+
+and put the definitions in the :attr:`tp_members` slot::
+
+ Noddy_members, /* tp_members */
+
+Each member definition has a member name, type, offset, access flags and
+documentation string. See the "Generic Attribute Management" section below for
+details.
+
+A disadvantage of this approach is that it doesn't provide a way to restrict the
+types of objects that can be assigned to the Python attributes. We expect the
+first and last names to be strings, but any Python objects can be assigned.
+Further, the attributes can be deleted, setting the C pointers to *NULL*. Even
+though we can make sure the members are initialized to non-*NULL* values, the
+members can be set to *NULL* if the attributes are deleted.
+
+We define a single method, :meth:`name`, that outputs the objects name as the
+concatenation of the first and last names. ::
+
+ static PyObject *
+ Noddy_name(Noddy* self)
+ {
+ static PyObject *format = NULL;
+ PyObject *args, *result;
+
+ if (format == NULL) {
+ format = PyString_FromString("%s %s");
+ if (format == NULL)
+ return NULL;
+ }
+
+ if (self->first == NULL) {
+ PyErr_SetString(PyExc_AttributeError, "first");
+ return NULL;
+ }
+
+ if (self->last == NULL) {
+ PyErr_SetString(PyExc_AttributeError, "last");
+ return NULL;
+ }
+
+ args = Py_BuildValue("OO", self->first, self->last);
+ if (args == NULL)
+ return NULL;
+
+ result = PyString_Format(format, args);
+ Py_DECREF(args);
+
+ return result;
+ }
+
+The method is implemented as a C function that takes a :class:`Noddy` (or
+:class:`Noddy` subclass) instance as the first argument. Methods always take an
+instance as the first argument. Methods often take positional and keyword
+arguments as well, but in this cased we don't take any and don't need to accept
+a positional argument tuple or keyword argument dictionary. This method is
+equivalent to the Python method::
+
+ def name(self):
+ return "%s %s" % (self.first, self.last)
+
+Note that we have to check for the possibility that our :attr:`first` and
+:attr:`last` members are *NULL*. This is because they can be deleted, in which
+case they are set to *NULL*. It would be better to prevent deletion of these
+attributes and to restrict the attribute values to be strings. We'll see how to
+do that in the next section.
+
+Now that we've defined the method, we need to create an array of method
+definitions::
+
+ static PyMethodDef Noddy_methods[] = {
+ {"name", (PyCFunction)Noddy_name, METH_NOARGS,
+ "Return the name, combining the first and last name"
+ },
+ {NULL} /* Sentinel */
+ };
+
+and assign them to the :attr:`tp_methods` slot::
+
+ Noddy_methods, /* tp_methods */
+
+Note that we used the :const:`METH_NOARGS` flag to indicate that the method is
+passed no arguments.
+
+Finally, we'll make our type usable as a base class. We've written our methods
+carefully so far so that they don't make any assumptions about the type of the
+object being created or used, so all we need to do is to add the
+:const:`Py_TPFLAGS_BASETYPE` to our class flag definition::
+
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+
+We rename :cfunc:`initnoddy` to :cfunc:`initnoddy2` and update the module name
+passed to :cfunc:`Py_InitModule3`.
+
+Finally, we update our :file:`setup.py` file to build the new module::
+
+ from distutils.core import setup, Extension
+ setup(name="noddy", version="1.0",
+ ext_modules=[
+ Extension("noddy", ["noddy.c"]),
+ Extension("noddy2", ["noddy2.c"]),
+ ])
+
+
+Providing finer control over data attributes
+--------------------------------------------
+
+In this section, we'll provide finer control over how the :attr:`first` and
+:attr:`last` attributes are set in the :class:`Noddy` example. In the previous
+version of our module, the instance variables :attr:`first` and :attr:`last`
+could be set to non-string values or even deleted. We want to make sure that
+these attributes always contain strings.
+
+.. literalinclude:: ../includes/noddy3.c
+
+
+To provide greater control, over the :attr:`first` and :attr:`last` attributes,
+we'll use custom getter and setter functions. Here are the functions for
+getting and setting the :attr:`first` attribute::
+
+ Noddy_getfirst(Noddy *self, void *closure)
+ {
+ Py_INCREF(self->first);
+ return self->first;
+ }
+
+ static int
+ Noddy_setfirst(Noddy *self, PyObject *value, void *closure)
+ {
+ if (value == NULL) {
+ PyErr_SetString(PyExc_TypeError, "Cannot delete the first attribute");
+ return -1;
+ }
+
+ if (! PyString_Check(value)) {
+ PyErr_SetString(PyExc_TypeError,
+ "The first attribute value must be a string");
+ return -1;
+ }
+
+ Py_DECREF(self->first);
+ Py_INCREF(value);
+ self->first = value;
+
+ return 0;
+ }
+
+The getter function is passed a :class:`Noddy` object and a "closure", which is
+void pointer. In this case, the closure is ignored. (The closure supports an
+advanced usage in which definition data is passed to the getter and setter. This
+could, for example, be used to allow a single set of getter and setter functions
+that decide the attribute to get or set based on data in the closure.)
+
+The setter function is passed the :class:`Noddy` object, the new value, and the
+closure. The new value may be *NULL*, in which case the attribute is being
+deleted. In our setter, we raise an error if the attribute is deleted or if the
+attribute value is not a string.
+
+We create an array of :ctype:`PyGetSetDef` structures::
+
+ static PyGetSetDef Noddy_getseters[] = {
+ {"first",
+ (getter)Noddy_getfirst, (setter)Noddy_setfirst,
+ "first name",
+ NULL},
+ {"last",
+ (getter)Noddy_getlast, (setter)Noddy_setlast,
+ "last name",
+ NULL},
+ {NULL} /* Sentinel */
+ };
+
+and register it in the :attr:`tp_getset` slot::
+
+ Noddy_getseters, /* tp_getset */
+
+to register out attribute getters and setters.
+
+The last item in a :ctype:`PyGetSetDef` structure is the closure mentioned
+above. In this case, we aren't using the closure, so we just pass *NULL*.
+
+We also remove the member definitions for these attributes::
+
+ static PyMemberDef Noddy_members[] = {
+ {"number", T_INT, offsetof(Noddy, number), 0,
+ "noddy number"},
+ {NULL} /* Sentinel */
+ };
+
+We also need to update the :attr:`tp_init` handler to only allow strings [#]_ to
+be passed::
+
+ static int
+ Noddy_init(Noddy *self, PyObject *args, PyObject *kwds)
+ {
+ PyObject *first=NULL, *last=NULL, *tmp;
+
+ static char *kwlist[] = {"first", "last", "number", NULL};
+
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|SSi", kwlist,
+ &first, &last,
+ &self->number))
+ return -1;
+
+ if (first) {
+ tmp = self->first;
+ Py_INCREF(first);
+ self->first = first;
+ Py_DECREF(tmp);
+ }
+
+ if (last) {
+ tmp = self->last;
+ Py_INCREF(last);
+ self->last = last;
+ Py_DECREF(tmp);
+ }
+
+ return 0;
+ }
+
+With these changes, we can assure that the :attr:`first` and :attr:`last`
+members are never *NULL* so we can remove checks for *NULL* values in almost all
+cases. This means that most of the :cfunc:`Py_XDECREF` calls can be converted to
+:cfunc:`Py_DECREF` calls. The only place we can't change these calls is in the
+deallocator, where there is the possibility that the initialization of these
+members failed in the constructor.
+
+We also rename the module initialization function and module name in the
+initialization function, as we did before, and we add an extra definition to the
+:file:`setup.py` file.
+
+
+Supporting cyclic garbage collection
+------------------------------------
+
+Python has a cyclic-garbage collector that can identify unneeded objects even
+when their reference counts are not zero. This can happen when objects are
+involved in cycles. For example, consider::
+
+ >>> l = []
+ >>> l.append(l)
+ >>> del l
+
+In this example, we create a list that contains itself. When we delete it, it
+still has a reference from itself. Its reference count doesn't drop to zero.
+Fortunately, Python's cyclic-garbage collector will eventually figure out that
+the list is garbage and free it.
+
+In the second version of the :class:`Noddy` example, we allowed any kind of
+object to be stored in the :attr:`first` or :attr:`last` attributes. [#]_ This
+means that :class:`Noddy` objects can participate in cycles::
+
+ >>> import noddy2
+ >>> n = noddy2.Noddy()
+ >>> l = [n]
+ >>> n.first = l
+
+This is pretty silly, but it gives us an excuse to add support for the
+cyclic-garbage collector to the :class:`Noddy` example. To support cyclic
+garbage collection, types need to fill two slots and set a class flag that
+enables these slots:
+
+.. literalinclude:: ../includes/noddy4.c
+
+
+The traversal method provides access to subobjects that could participate in
+cycles::
+
+ static int
+ Noddy_traverse(Noddy *self, visitproc visit, void *arg)
+ {
+ int vret;
+
+ if (self->first) {
+ vret = visit(self->first, arg);
+ if (vret != 0)
+ return vret;
+ }
+ if (self->last) {
+ vret = visit(self->last, arg);
+ if (vret != 0)
+ return vret;
+ }
+
+ return 0;
+ }
+
+For each subobject that can participate in cycles, we need to call the
+:cfunc:`visit` function, which is passed to the traversal method. The
+:cfunc:`visit` function takes as arguments the subobject and the extra argument
+*arg* passed to the traversal method. It returns an integer value that must be
+returned if it is non-zero.
+
+Python 2.4 and higher provide a :cfunc:`Py_VISIT` macro that automates calling
+visit functions. With :cfunc:`Py_VISIT`, :cfunc:`Noddy_traverse` can be
+simplified::
+
+ static int
+ Noddy_traverse(Noddy *self, visitproc visit, void *arg)
+ {
+ Py_VISIT(self->first);
+ Py_VISIT(self->last);
+ return 0;
+ }
+
+.. note::
+
+ Note that the :attr:`tp_traverse` implementation must name its arguments exactly
+ *visit* and *arg* in order to use :cfunc:`Py_VISIT`. This is to encourage
+ uniformity across these boring implementations.
+
+We also need to provide a method for clearing any subobjects that can
+participate in cycles. We implement the method and reimplement the deallocator
+to use it::
+
+ static int
+ Noddy_clear(Noddy *self)
+ {
+ PyObject *tmp;
+
+ tmp = self->first;
+ self->first = NULL;
+ Py_XDECREF(tmp);
+
+ tmp = self->last;
+ self->last = NULL;
+ Py_XDECREF(tmp);
+
+ return 0;
+ }
+
+ static void
+ Noddy_dealloc(Noddy* self)
+ {
+ Noddy_clear(self);
+ self->ob_type->tp_free((PyObject*)self);
+ }
+
+Notice the use of a temporary variable in :cfunc:`Noddy_clear`. We use the
+temporary variable so that we can set each member to *NULL* before decrementing
+its reference count. We do this because, as was discussed earlier, if the
+reference count drops to zero, we might cause code to run that calls back into
+the object. In addition, because we now support garbage collection, we also
+have to worry about code being run that triggers garbage collection. If garbage
+collection is run, our :attr:`tp_traverse` handler could get called. We can't
+take a chance of having :cfunc:`Noddy_traverse` called when a member's reference
+count has dropped to zero and its value hasn't been set to *NULL*.
+
+Python 2.4 and higher provide a :cfunc:`Py_CLEAR` that automates the careful
+decrementing of reference counts. With :cfunc:`Py_CLEAR`, the
+:cfunc:`Noddy_clear` function can be simplified::
+
+ static int
+ Noddy_clear(Noddy *self)
+ {
+ Py_CLEAR(self->first);
+ Py_CLEAR(self->last);
+ return 0;
+ }
+
+Finally, we add the :const:`Py_TPFLAGS_HAVE_GC` flag to the class flags::
+
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+
+That's pretty much it. If we had written custom :attr:`tp_alloc` or
+:attr:`tp_free` slots, we'd need to modify them for cyclic-garbage collection.
+Most extensions will use the versions automatically provided.
+
+
+Subclassing other types
+-----------------------
+
+It is possible to create new extension types that are derived from existing
+types. It is easiest to inherit from the built in types, since an extension can
+easily use the :class:`PyTypeObject` it needs. It can be difficult to share
+these :class:`PyTypeObject` structures between extension modules.
+
+In this example we will create a :class:`Shoddy` type that inherits from the
+builtin :class:`list` type. The new type will be completely compatible with
+regular lists, but will have an additional :meth:`increment` method that
+increases an internal counter. ::
+
+ >>> import shoddy
+ >>> s = shoddy.Shoddy(range(3))
+ >>> s.extend(s)
+ >>> print len(s)
+ 6
+ >>> print s.increment()
+ 1
+ >>> print s.increment()
+ 2
+
+.. literalinclude:: ../includes/shoddy.c
+
+
+As you can see, the source code closely resembles the :class:`Noddy` examples in
+previous sections. We will break down the main differences between them. ::
+
+ typedef struct {
+ PyListObject list;
+ int state;
+ } Shoddy;
+
+The primary difference for derived type objects is that the base type's object
+structure must be the first value. The base type will already include the
+:cfunc:`PyObject_HEAD` at the beginning of its structure.
+
+When a Python object is a :class:`Shoddy` instance, its *PyObject\** pointer can
+be safely cast to both *PyListObject\** and *Shoddy\**. ::
+
+ static int
+ Shoddy_init(Shoddy *self, PyObject *args, PyObject *kwds)
+ {
+ if (PyList_Type.tp_init((PyObject *)self, args, kwds) < 0)
+ return -1;
+ self->state = 0;
+ return 0;
+ }
+
+In the :attr:`__init__` method for our type, we can see how to call through to
+the :attr:`__init__` method of the base type.
+
+This pattern is important when writing a type with custom :attr:`new` and
+:attr:`dealloc` methods. The :attr:`new` method should not actually create the
+memory for the object with :attr:`tp_alloc`, that will be handled by the base
+class when calling its :attr:`tp_new`.
+
+When filling out the :cfunc:`PyTypeObject` for the :class:`Shoddy` type, you see
+a slot for :cfunc:`tp_base`. Due to cross platform compiler issues, you can't
+fill that field directly with the :cfunc:`PyList_Type`; it can be done later in
+the module's :cfunc:`init` function. ::
+
+ PyMODINIT_FUNC
+ initshoddy(void)
+ {
+ PyObject *m;
+
+ ShoddyType.tp_base = &PyList_Type;
+ if (PyType_Ready(&ShoddyType) < 0)
+ return;
+
+ m = Py_InitModule3("shoddy", NULL, "Shoddy module");
+ if (m == NULL)
+ return;
+
+ Py_INCREF(&ShoddyType);
+ PyModule_AddObject(m, "Shoddy", (PyObject *) &ShoddyType);
+ }
+
+Before calling :cfunc:`PyType_Ready`, the type structure must have the
+:attr:`tp_base` slot filled in. When we are deriving a new type, it is not
+necessary to fill out the :attr:`tp_alloc` slot with :cfunc:`PyType_GenericNew`
+-- the allocate function from the base type will be inherited.
+
+After that, calling :cfunc:`PyType_Ready` and adding the type object to the
+module is the same as with the basic :class:`Noddy` examples.
+
+
+.. _dnt-type-methods:
+
+Type Methods
+============
+
+This section aims to give a quick fly-by on the various type methods you can
+implement and what they do.
+
+Here is the definition of :ctype:`PyTypeObject`, with some fields only used in
+debug builds omitted:
+
+.. literalinclude:: ../includes/typestruct.h
+
+
+Now that's a *lot* of methods. Don't worry too much though - if you have a type
+you want to define, the chances are very good that you will only implement a
+handful of these.
+
+As you probably expect by now, we're going to go over this and give more
+information about the various handlers. We won't go in the order they are
+defined in the structure, because there is a lot of historical baggage that
+impacts the ordering of the fields; be sure your type initialization keeps the
+fields in the right order! It's often easiest to find an example that includes
+all the fields you need (even if they're initialized to ``0``) and then change
+the values to suit your new type. ::
+
+ char *tp_name; /* For printing */
+
+The name of the type - as mentioned in the last section, this will appear in
+various places, almost entirely for diagnostic purposes. Try to choose something
+that will be helpful in such a situation! ::
+
+ int tp_basicsize, tp_itemsize; /* For allocation */
+
+These fields tell the runtime how much memory to allocate when new objects of
+this type are created. Python has some built-in support for variable length
+structures (think: strings, lists) which is where the :attr:`tp_itemsize` field
+comes in. This will be dealt with later. ::
+
+ char *tp_doc;
+
+Here you can put a string (or its address) that you want returned when the
+Python script references ``obj.__doc__`` to retrieve the doc string.
+
+Now we come to the basic type methods---the ones most extension types will
+implement.
+
+
+Finalization and De-allocation
+------------------------------
+
+.. index::
+ single: object; deallocation
+ single: deallocation, object
+ single: object; finalization
+ single: finalization, of objects
+
+::
+
+ destructor tp_dealloc;
+
+This function is called when the reference count of the instance of your type is
+reduced to zero and the Python interpreter wants to reclaim it. If your type
+has memory to free or other clean-up to perform, put it here. The object itself
+needs to be freed here as well. Here is an example of this function::
+
+ static void
+ newdatatype_dealloc(newdatatypeobject * obj)
+ {
+ free(obj->obj_UnderlyingDatatypePtr);
+ obj->ob_type->tp_free(obj);
+ }
+
+.. index::
+ single: PyErr_Fetch()
+ single: PyErr_Restore()
+
+One important requirement of the deallocator function is that it leaves any
+pending exceptions alone. This is important since deallocators are frequently
+called as the interpreter unwinds the Python stack; when the stack is unwound
+due to an exception (rather than normal returns), nothing is done to protect the
+deallocators from seeing that an exception has already been set. Any actions
+which a deallocator performs which may cause additional Python code to be
+executed may detect that an exception has been set. This can lead to misleading
+errors from the interpreter. The proper way to protect against this is to save
+a pending exception before performing the unsafe action, and restoring it when
+done. This can be done using the :cfunc:`PyErr_Fetch` and
+:cfunc:`PyErr_Restore` functions::
+
+ static void
+ my_dealloc(PyObject *obj)
+ {
+ MyObject *self = (MyObject *) obj;
+ PyObject *cbresult;
+
+ if (self->my_callback != NULL) {
+ PyObject *err_type, *err_value, *err_traceback;
+ int have_error = PyErr_Occurred() ? 1 : 0;
+
+ if (have_error)
+ PyErr_Fetch(&err_type, &err_value, &err_traceback);
+
+ cbresult = PyObject_CallObject(self->my_callback, NULL);
+ if (cbresult == NULL)
+ PyErr_WriteUnraisable(self->my_callback);
+ else
+ Py_DECREF(cbresult);
+
+ if (have_error)
+ PyErr_Restore(err_type, err_value, err_traceback);
+
+ Py_DECREF(self->my_callback);
+ }
+ obj->ob_type->tp_free((PyObject*)self);
+ }
+
+
+Object Presentation
+-------------------
+
+.. index::
+ builtin: repr
+ builtin: str
+
+In Python, there are two ways to generate a textual representation of an object:
+the :func:`repr` function, and the :func:`str` function. (The :func:`print`
+function just calls :func:`str`.) These handlers are both optional.
+
+::
+
+ reprfunc tp_repr;
+ reprfunc tp_str;
+
+The :attr:`tp_repr` handler should return a string object containing a
+representation of the instance for which it is called. Here is a simple
+example::
+
+ static PyObject *
+ newdatatype_repr(newdatatypeobject * obj)
+ {
+ return PyString_FromFormat("Repr-ified_newdatatype{{size:\%d}}",
+ obj->obj_UnderlyingDatatypePtr->size);
+ }
+
+If no :attr:`tp_repr` handler is specified, the interpreter will supply a
+representation that uses the type's :attr:`tp_name` and a uniquely-identifying
+value for the object.
+
+The :attr:`tp_str` handler is to :func:`str` what the :attr:`tp_repr` handler
+described above is to :func:`repr`; that is, it is called when Python code calls
+:func:`str` on an instance of your object. Its implementation is very similar
+to the :attr:`tp_repr` function, but the resulting string is intended for human
+consumption. If :attr:`tp_str` is not specified, the :attr:`tp_repr` handler is
+used instead.
+
+Here is a simple example::
+
+ static PyObject *
+ newdatatype_str(newdatatypeobject * obj)
+ {
+ return PyString_FromFormat("Stringified_newdatatype{{size:\%d}}",
+ obj->obj_UnderlyingDatatypePtr->size);
+ }
+
+The print function will be called whenever Python needs to "print" an instance
+of the type. For example, if 'node' is an instance of type TreeNode, then the
+print function is called when Python code calls::
+
+ print node
+
+There is a flags argument and one flag, :const:`Py_PRINT_RAW`, and it suggests
+that you print without string quotes and possibly without interpreting escape
+sequences.
+
+The print function receives a file object as an argument. You will likely want
+to write to that file object.
+
+Here is a sample print function::
+
+ static int
+ newdatatype_print(newdatatypeobject *obj, FILE *fp, int flags)
+ {
+ if (flags & Py_PRINT_RAW) {
+ fprintf(fp, "<{newdatatype object--size: %d}>",
+ obj->obj_UnderlyingDatatypePtr->size);
+ }
+ else {
+ fprintf(fp, "\"<{newdatatype object--size: %d}>\"",
+ obj->obj_UnderlyingDatatypePtr->size);
+ }
+ return 0;
+ }
+
+
+Attribute Management
+--------------------
+
+For every object which can support attributes, the corresponding type must
+provide the functions that control how the attributes are resolved. There needs
+to be a function which can retrieve attributes (if any are defined), and another
+to set attributes (if setting attributes is allowed). Removing an attribute is
+a special case, for which the new value passed to the handler is *NULL*.
+
+Python supports two pairs of attribute handlers; a type that supports attributes
+only needs to implement the functions for one pair. The difference is that one
+pair takes the name of the attribute as a :ctype:`char\*`, while the other
+accepts a :ctype:`PyObject\*`. Each type can use whichever pair makes more
+sense for the implementation's convenience. ::
+
+ getattrfunc tp_getattr; /* char * version */
+ setattrfunc tp_setattr;
+ /* ... */
+ getattrofunc tp_getattrofunc; /* PyObject * version */
+ setattrofunc tp_setattrofunc;
+
+If accessing attributes of an object is always a simple operation (this will be
+explained shortly), there are generic implementations which can be used to
+provide the :ctype:`PyObject\*` version of the attribute management functions.
+The actual need for type-specific attribute handlers almost completely
+disappeared starting with Python 2.2, though there are many examples which have
+not been updated to use some of the new generic mechanism that is available.
+
+
+Generic Attribute Management
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. versionadded:: 2.2
+
+Most extension types only use *simple* attributes. So, what makes the
+attributes simple? There are only a couple of conditions that must be met:
+
+#. The name of the attributes must be known when :cfunc:`PyType_Ready` is
+ called.
+
+#. No special processing is needed to record that an attribute was looked up or
+ set, nor do actions need to be taken based on the value.
+
+Note that this list does not place any restrictions on the values of the
+attributes, when the values are computed, or how relevant data is stored.
+
+When :cfunc:`PyType_Ready` is called, it uses three tables referenced by the
+type object to create *descriptors* which are placed in the dictionary of the
+type object. Each descriptor controls access to one attribute of the instance
+object. Each of the tables is optional; if all three are *NULL*, instances of
+the type will only have attributes that are inherited from their base type, and
+should leave the :attr:`tp_getattro` and :attr:`tp_setattro` fields *NULL* as
+well, allowing the base type to handle attributes.
+
+The tables are declared as three fields of the type object::
+
+ struct PyMethodDef *tp_methods;
+ struct PyMemberDef *tp_members;
+ struct PyGetSetDef *tp_getset;
+
+If :attr:`tp_methods` is not *NULL*, it must refer to an array of
+:ctype:`PyMethodDef` structures. Each entry in the table is an instance of this
+structure::
+
+ typedef struct PyMethodDef {
+ char *ml_name; /* method name */
+ PyCFunction ml_meth; /* implementation function */
+ int ml_flags; /* flags */
+ char *ml_doc; /* docstring */
+ } PyMethodDef;
+
+One entry should be defined for each method provided by the type; no entries are
+needed for methods inherited from a base type. One additional entry is needed
+at the end; it is a sentinel that marks the end of the array. The
+:attr:`ml_name` field of the sentinel must be *NULL*.
+
+XXX Need to refer to some unified discussion of the structure fields, shared
+with the next section.
+
+The second table is used to define attributes which map directly to data stored
+in the instance. A variety of primitive C types are supported, and access may
+be read-only or read-write. The structures in the table are defined as::
+
+ typedef struct PyMemberDef {
+ char *name;
+ int type;
+ int offset;
+ int flags;
+ char *doc;
+ } PyMemberDef;
+
+For each entry in the table, a descriptor will be constructed and added to the
+type which will be able to extract a value from the instance structure. The
+:attr:`type` field should contain one of the type codes defined in the
+:file:`structmember.h` header; the value will be used to determine how to
+convert Python values to and from C values. The :attr:`flags` field is used to
+store flags which control how the attribute can be accessed.
+
+XXX Need to move some of this to a shared section!
+
+The following flag constants are defined in :file:`structmember.h`; they may be
+combined using bitwise-OR.
+
++---------------------------+----------------------------------------------+
+| Constant | Meaning |
++===========================+==============================================+
+| :const:`READONLY` | Never writable. |
++---------------------------+----------------------------------------------+
+| :const:`RO` | Shorthand for :const:`READONLY`. |
++---------------------------+----------------------------------------------+
+| :const:`READ_RESTRICTED` | Not readable in restricted mode. |
++---------------------------+----------------------------------------------+
+| :const:`WRITE_RESTRICTED` | Not writable in restricted mode. |
++---------------------------+----------------------------------------------+
+| :const:`RESTRICTED` | Not readable or writable in restricted mode. |
++---------------------------+----------------------------------------------+
+
+.. index::
+ single: READONLY
+ single: RO
+ single: READ_RESTRICTED
+ single: WRITE_RESTRICTED
+ single: RESTRICTED
+
+An interesting advantage of using the :attr:`tp_members` table to build
+descriptors that are used at runtime is that any attribute defined this way can
+have an associated doc string simply by providing the text in the table. An
+application can use the introspection API to retrieve the descriptor from the
+class object, and get the doc string using its :attr:`__doc__` attribute.
+
+As with the :attr:`tp_methods` table, a sentinel entry with a :attr:`name` value
+of *NULL* is required.
+
+.. % XXX Descriptors need to be explained in more detail somewhere, but
+.. % not here.
+.. %
+.. % Descriptor objects have two handler functions which correspond to
+.. % the \member{tp_getattro} and \member{tp_setattro} handlers. The
+.. % \method{__get__()} handler is a function which is passed the
+.. % descriptor, instance, and type objects, and returns the value of the
+.. % attribute, or it returns \NULL{} and sets an exception. The
+.. % \method{__set__()} handler is passed the descriptor, instance, type,
+.. % and new value;
+
+
+Type-specific Attribute Management
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+For simplicity, only the :ctype:`char\*` version will be demonstrated here; the
+type of the name parameter is the only difference between the :ctype:`char\*`
+and :ctype:`PyObject\*` flavors of the interface. This example effectively does
+the same thing as the generic example above, but does not use the generic
+support added in Python 2.2. The value in showing this is two-fold: it
+demonstrates how basic attribute management can be done in a way that is
+portable to older versions of Python, and explains how the handler functions are
+called, so that if you do need to extend their functionality, you'll understand
+what needs to be done.
+
+The :attr:`tp_getattr` handler is called when the object requires an attribute
+look-up. It is called in the same situations where the :meth:`__getattr__`
+method of a class would be called.
+
+A likely way to handle this is (1) to implement a set of functions (such as
+:cfunc:`newdatatype_getSize` and :cfunc:`newdatatype_setSize` in the example
+below), (2) provide a method table listing these functions, and (3) provide a
+getattr function that returns the result of a lookup in that table. The method
+table uses the same structure as the :attr:`tp_methods` field of the type
+object.
+
+Here is an example::
+
+ static PyMethodDef newdatatype_methods[] = {
+ {"getSize", (PyCFunction)newdatatype_getSize, METH_VARARGS,
+ "Return the current size."},
+ {"setSize", (PyCFunction)newdatatype_setSize, METH_VARARGS,
+ "Set the size."},
+ {NULL, NULL, 0, NULL} /* sentinel */
+ };
+
+ static PyObject *
+ newdatatype_getattr(newdatatypeobject *obj, char *name)
+ {
+ return Py_FindMethod(newdatatype_methods, (PyObject *)obj, name);
+ }
+
+The :attr:`tp_setattr` handler is called when the :meth:`__setattr__` or
+:meth:`__delattr__` method of a class instance would be called. When an
+attribute should be deleted, the third parameter will be *NULL*. Here is an
+example that simply raises an exception; if this were really all you wanted, the
+:attr:`tp_setattr` handler should be set to *NULL*. ::
+
+ static int
+ newdatatype_setattr(newdatatypeobject *obj, char *name, PyObject *v)
+ {
+ (void)PyErr_Format(PyExc_RuntimeError, "Read-only attribute: \%s", name);
+ return -1;
+ }
+
+
+Object Comparison
+-----------------
+
+::
+
+ cmpfunc tp_compare;
+
+The :attr:`tp_compare` handler is called when comparisons are needed and the
+object does not implement the specific rich comparison method which matches the
+requested comparison. (It is always used if defined and the
+:cfunc:`PyObject_Compare` or :cfunc:`PyObject_Cmp` functions are used, or if
+:func:`cmp` is used from Python.) It is analogous to the :meth:`__cmp__` method.
+This function should return ``-1`` if *obj1* is less than *obj2*, ``0`` if they
+are equal, and ``1`` if *obj1* is greater than *obj2*. (It was previously
+allowed to return arbitrary negative or positive integers for less than and
+greater than, respectively; as of Python 2.2, this is no longer allowed. In the
+future, other return values may be assigned a different meaning.)
+
+A :attr:`tp_compare` handler may raise an exception. In this case it should
+return a negative value. The caller has to test for the exception using
+:cfunc:`PyErr_Occurred`.
+
+Here is a sample implementation::
+
+ static int
+ newdatatype_compare(newdatatypeobject * obj1, newdatatypeobject * obj2)
+ {
+ long result;
+
+ if (obj1->obj_UnderlyingDatatypePtr->size <
+ obj2->obj_UnderlyingDatatypePtr->size) {
+ result = -1;
+ }
+ else if (obj1->obj_UnderlyingDatatypePtr->size >
+ obj2->obj_UnderlyingDatatypePtr->size) {
+ result = 1;
+ }
+ else {
+ result = 0;
+ }
+ return result;
+ }
+
+
+Abstract Protocol Support
+-------------------------
+
+Python supports a variety of *abstract* 'protocols;' the specific interfaces
+provided to use these interfaces are documented in :ref:`abstract`.
+
+
+A number of these abstract interfaces were defined early in the development of
+the Python implementation. In particular, the number, mapping, and sequence
+protocols have been part of Python since the beginning. Other protocols have
+been added over time. For protocols which depend on several handler routines
+from the type implementation, the older protocols have been defined as optional
+blocks of handlers referenced by the type object. For newer protocols there are
+additional slots in the main type object, with a flag bit being set to indicate
+that the slots are present and should be checked by the interpreter. (The flag
+bit does not indicate that the slot values are non-*NULL*. The flag may be set
+to indicate the presence of a slot, but a slot may still be unfilled.) ::
+
+ PyNumberMethods tp_as_number;
+ PySequenceMethods tp_as_sequence;
+ PyMappingMethods tp_as_mapping;
+
+If you wish your object to be able to act like a number, a sequence, or a
+mapping object, then you place the address of a structure that implements the C
+type :ctype:`PyNumberMethods`, :ctype:`PySequenceMethods`, or
+:ctype:`PyMappingMethods`, respectively. It is up to you to fill in this
+structure with appropriate values. You can find examples of the use of each of
+these in the :file:`Objects` directory of the Python source distribution. ::
+
+ hashfunc tp_hash;
+
+This function, if you choose to provide it, should return a hash number for an
+instance of your data type. Here is a moderately pointless example::
+
+ static long
+ newdatatype_hash(newdatatypeobject *obj)
+ {
+ long result;
+ result = obj->obj_UnderlyingDatatypePtr->size;
+ result = result * 3;
+ return result;
+ }
+
+::
+
+ ternaryfunc tp_call;
+
+This function is called when an instance of your data type is "called", for
+example, if ``obj1`` is an instance of your data type and the Python script
+contains ``obj1('hello')``, the :attr:`tp_call` handler is invoked.
+
+This function takes three arguments:
+
+#. *arg1* is the instance of the data type which is the subject of the call. If
+ the call is ``obj1('hello')``, then *arg1* is ``obj1``.
+
+#. *arg2* is a tuple containing the arguments to the call. You can use
+ :cfunc:`PyArg_ParseTuple` to extract the arguments.
+
+#. *arg3* is a dictionary of keyword arguments that were passed. If this is
+ non-*NULL* and you support keyword arguments, use
+ :cfunc:`PyArg_ParseTupleAndKeywords` to extract the arguments. If you do not
+ want to support keyword arguments and this is non-*NULL*, raise a
+ :exc:`TypeError` with a message saying that keyword arguments are not supported.
+
+Here is a desultory example of the implementation of the call function. ::
+
+ /* Implement the call function.
+ * obj1 is the instance receiving the call.
+ * obj2 is a tuple containing the arguments to the call, in this
+ * case 3 strings.
+ */
+ static PyObject *
+ newdatatype_call(newdatatypeobject *obj, PyObject *args, PyObject *other)
+ {
+ PyObject *result;
+ char *arg1;
+ char *arg2;
+ char *arg3;
+
+ if (!PyArg_ParseTuple(args, "sss:call", &arg1, &arg2, &arg3)) {
+ return NULL;
+ }
+ result = PyString_FromFormat(
+ "Returning -- value: [\%d] arg1: [\%s] arg2: [\%s] arg3: [\%s]\n",
+ obj->obj_UnderlyingDatatypePtr->size,
+ arg1, arg2, arg3);
+ printf("\%s", PyString_AS_STRING(result));
+ return result;
+ }
+
+XXX some fields need to be added here... ::
+
+ /* Added in release 2.2 */
+ /* Iterators */
+ getiterfunc tp_iter;
+ iternextfunc tp_iternext;
+
+These functions provide support for the iterator protocol. Any object which
+wishes to support iteration over its contents (which may be generated during
+iteration) must implement the ``tp_iter`` handler. Objects which are returned
+by a ``tp_iter`` handler must implement both the ``tp_iter`` and ``tp_iternext``
+handlers. Both handlers take exactly one parameter, the instance for which they
+are being called, and return a new reference. In the case of an error, they
+should set an exception and return *NULL*.
+
+For an object which represents an iterable collection, the ``tp_iter`` handler
+must return an iterator object. The iterator object is responsible for
+maintaining the state of the iteration. For collections which can support
+multiple iterators which do not interfere with each other (as lists and tuples
+do), a new iterator should be created and returned. Objects which can only be
+iterated over once (usually due to side effects of iteration) should implement
+this handler by returning a new reference to themselves, and should also
+implement the ``tp_iternext`` handler. File objects are an example of such an
+iterator.
+
+Iterator objects should implement both handlers. The ``tp_iter`` handler should
+return a new reference to the iterator (this is the same as the ``tp_iter``
+handler for objects which can only be iterated over destructively). The
+``tp_iternext`` handler should return a new reference to the next object in the
+iteration if there is one. If the iteration has reached the end, it may return
+*NULL* without setting an exception or it may set :exc:`StopIteration`; avoiding
+the exception can yield slightly better performance. If an actual error occurs,
+it should set an exception and return *NULL*.
+
+
+.. _weakref-support:
+
+Weak Reference Support
+----------------------
+
+One of the goals of Python's weak-reference implementation is to allow any type
+to participate in the weak reference mechanism without incurring the overhead on
+those objects which do not benefit by weak referencing (such as numbers).
+
+For an object to be weakly referencable, the extension must include a
+:ctype:`PyObject\*` field in the instance structure for the use of the weak
+reference mechanism; it must be initialized to *NULL* by the object's
+constructor. It must also set the :attr:`tp_weaklistoffset` field of the
+corresponding type object to the offset of the field. For example, the instance
+type is defined with the following structure::
+
+ typedef struct {
+ PyObject_HEAD
+ PyClassObject *in_class; /* The class object */
+ PyObject *in_dict; /* A dictionary */
+ PyObject *in_weakreflist; /* List of weak references */
+ } PyInstanceObject;
+
+The statically-declared type object for instances is defined this way::
+
+ PyTypeObject PyInstance_Type = {
+ PyObject_HEAD_INIT(&PyType_Type)
+ 0,
+ "module.instance",
+
+ /* Lots of stuff omitted for brevity... */
+
+ Py_TPFLAGS_DEFAULT, /* tp_flags */
+ 0, /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ offsetof(PyInstanceObject, in_weakreflist), /* tp_weaklistoffset */
+ };
+
+The type constructor is responsible for initializing the weak reference list to
+*NULL*::
+
+ static PyObject *
+ instance_new() {
+ /* Other initialization stuff omitted for brevity */
+
+ self->in_weakreflist = NULL;
+
+ return (PyObject *) self;
+ }
+
+The only further addition is that the destructor needs to call the weak
+reference manager to clear any weak references. This should be done before any
+other parts of the destruction have occurred, but is only required if the weak
+reference list is non-*NULL*::
+
+ static void
+ instance_dealloc(PyInstanceObject *inst)
+ {
+ /* Allocate temporaries if needed, but do not begin
+ destruction just yet.
+ */
+
+ if (inst->in_weakreflist != NULL)
+ PyObject_ClearWeakRefs((PyObject *) inst);
+
+ /* Proceed with object destruction normally. */
+ }
+
+
+More Suggestions
+----------------
+
+Remember that you can omit most of these functions, in which case you provide
+``0`` as a value. There are type definitions for each of the functions you must
+provide. They are in :file:`object.h` in the Python include directory that
+comes with the source distribution of Python.
+
+In order to learn how to implement any specific method for your new data type,
+do the following: Download and unpack the Python source distribution. Go the
+:file:`Objects` directory, then search the C source files for ``tp_`` plus the
+function you want (for example, ``tp_compare``). You will find examples of the
+function you want to implement.
+
+When you need to verify that an object is an instance of the type you are
+implementing, use the :cfunc:`PyObject_TypeCheck` function. A sample of its use
+might be something like the following::
+
+ if (! PyObject_TypeCheck(some_object, &MyType)) {
+ PyErr_SetString(PyExc_TypeError, "arg #1 not a mything");
+ return NULL;
+ }
+
+.. rubric:: Footnotes
+
+.. [#] This is true when we know that the object is a basic type, like a string or a
+ float.
+
+.. [#] We relied on this in the :attr:`tp_dealloc` handler in this example, because our
+ type doesn't support garbage collection. Even if a type supports garbage
+ collection, there are calls that can be made to "untrack" the object from
+ garbage collection, however, these calls are advanced and not covered here.
+
+.. [#] We now know that the first and last members are strings, so perhaps we could be
+ less careful about decrementing their reference counts, however, we accept
+ instances of string subclasses. Even though deallocating normal strings won't
+ call back into our objects, we can't guarantee that deallocating an instance of
+ a string subclass won't. call back into out objects.
+
+.. [#] Even in the third version, we aren't guaranteed to avoid cycles. Instances of
+ string subclasses are allowed and string subclasses could allow cycles even if
+ normal strings don't.
+
diff --git a/Doc/extending/windows.rst b/Doc/extending/windows.rst
new file mode 100644
index 0000000000..7a66afe645
--- /dev/null
+++ b/Doc/extending/windows.rst
@@ -0,0 +1,280 @@
+.. highlightlang:: c
+
+
+.. _building-on-windows:
+
+****************************************
+Building C and C++ Extensions on Windows
+****************************************
+
+.. %
+
+This chapter briefly explains how to create a Windows extension module for
+Python using Microsoft Visual C++, and follows with more detailed background
+information on how it works. The explanatory material is useful for both the
+Windows programmer learning to build Python extensions and the Unix programmer
+interested in producing software which can be successfully built on both Unix
+and Windows.
+
+Module authors are encouraged to use the distutils approach for building
+extension modules, instead of the one described in this section. You will still
+need the C compiler that was used to build Python; typically Microsoft Visual
+C++.
+
+.. note::
+
+ This chapter mentions a number of filenames that include an encoded Python
+ version number. These filenames are represented with the version number shown
+ as ``XY``; in practive, ``'X'`` will be the major version number and ``'Y'``
+ will be the minor version number of the Python release you're working with. For
+ example, if you are using Python 2.2.1, ``XY`` will actually be ``22``.
+
+
+.. _win-cookbook:
+
+A Cookbook Approach
+===================
+
+There are two approaches to building extension modules on Windows, just as there
+are on Unix: use the :mod:`distutils` package to control the build process, or
+do things manually. The distutils approach works well for most extensions;
+documentation on using :mod:`distutils` to build and package extension modules
+is available in :ref:`distutils-index`. This section describes the manual
+approach to building Python extensions written in C or C++.
+
+To build extensions using these instructions, you need to have a copy of the
+Python sources of the same version as your installed Python. You will need
+Microsoft Visual C++ "Developer Studio"; project files are supplied for VC++
+version 7.1, but you can use older versions of VC++. Notice that you should use
+the same version of VC++that was used to build Python itself. The example files
+described here are distributed with the Python sources in the
+:file:`PC\\example_nt\\` directory.
+
+#. **Copy the example files** --- The :file:`example_nt` directory is a
+ subdirectory of the :file:`PC` directory, in order to keep all the PC-specific
+ files under the same directory in the source distribution. However, the
+ :file:`example_nt` directory can't actually be used from this location. You
+ first need to copy or move it up one level, so that :file:`example_nt` is a
+ sibling of the :file:`PC` and :file:`Include` directories. Do all your work
+ from within this new location.
+
+#. **Open the project** --- From VC++, use the :menuselection:`File --> Open
+ Solution` dialog (not :menuselection:`File --> Open`!). Navigate to and select
+ the file :file:`example.sln`, in the *copy* of the :file:`example_nt` directory
+ you made above. Click Open.
+
+#. **Build the example DLL** --- In order to check that everything is set up
+ right, try building:
+
+#. Select a configuration. This step is optional. Choose
+ :menuselection:`Build --> Configuration Manager --> Active Solution Configuration`
+ and select either :guilabel:`Release` or :guilabel:`Debug`. If you skip this
+ step, VC++ will use the Debug configuration by default.
+
+#. Build the DLL. Choose :menuselection:`Build --> Build Solution`. This
+ creates all intermediate and result files in a subdirectory called either
+ :file:`Debug` or :file:`Release`, depending on which configuration you selected
+ in the preceding step.
+
+#. **Testing the debug-mode DLL** --- Once the Debug build has succeeded, bring
+ up a DOS box, and change to the :file:`example_nt\\Debug` directory. You should
+ now be able to repeat the following session (``C>`` is the DOS prompt, ``>>>``
+ is the Python prompt; note that build information and various debug output from
+ Python may not match this screen dump exactly)::
+
+ C>..\..\PCbuild\python_d
+ Adding parser accelerators ...
+ Done.
+ Python 2.2 (#28, Dec 19 2001, 23:26:37) [MSC 32 bit (Intel)] on win32
+ Type "copyright", "credits" or "license" for more information.
+ >>> import example
+ [4897 refs]
+ >>> example.foo()
+ Hello, world
+ [4903 refs]
+ >>>
+
+ Congratulations! You've successfully built your first Python extension module.
+
+#. **Creating your own project** --- Choose a name and create a directory for
+ it. Copy your C sources into it. Note that the module source file name does
+ not necessarily have to match the module name, but the name of the
+ initialization function should match the module name --- you can only import a
+ module :mod:`spam` if its initialization function is called :cfunc:`initspam`,
+ and it should call :cfunc:`Py_InitModule` with the string ``"spam"`` as its
+ first argument (use the minimal :file:`example.c` in this directory as a guide).
+ By convention, it lives in a file called :file:`spam.c` or :file:`spammodule.c`.
+ The output file should be called :file:`spam.dll` or :file:`spam.pyd` (the
+ latter is supported to avoid confusion with a system library :file:`spam.dll` to
+ which your module could be a Python interface) in Release mode, or
+ :file:`spam_d.dll` or :file:`spam_d.pyd` in Debug mode.
+
+ Now your options are:
+
+#. Copy :file:`example.sln` and :file:`example.vcproj`, rename them to
+ :file:`spam.\*`, and edit them by hand, or
+
+#. Create a brand new project; instructions are below.
+
+ In either case, copy :file:`example_nt\\example.def` to :file:`spam\\spam.def`,
+ and edit the new :file:`spam.def` so its second line contains the string
+ '``initspam``'. If you created a new project yourself, add the file
+ :file:`spam.def` to the project now. (This is an annoying little file with only
+ two lines. An alternative approach is to forget about the :file:`.def` file,
+ and add the option :option:`/export:initspam` somewhere to the Link settings, by
+ manually editing the setting in Project Properties dialog).
+
+#. **Creating a brand new project** --- Use the :menuselection:`File --> New
+ --> Project` dialog to create a new Project Workspace. Select :guilabel:`Visual
+ C++ Projects/Win32/ Win32 Project`, enter the name (``spam``), and make sure the
+ Location is set to parent of the :file:`spam` directory you have created (which
+ should be a direct subdirectory of the Python build tree, a sibling of
+ :file:`Include` and :file:`PC`). Select Win32 as the platform (in my version,
+ this is the only choice). Make sure the Create new workspace radio button is
+ selected. Click OK.
+
+ You should now create the file :file:`spam.def` as instructed in the previous
+ section. Add the source files to the project, using :menuselection:`Project -->
+ Add Existing Item`. Set the pattern to ``*.*`` and select both :file:`spam.c`
+ and :file:`spam.def` and click OK. (Inserting them one by one is fine too.)
+
+ Now open the :menuselection:`Project --> spam properties` dialog. You only need
+ to change a few settings. Make sure :guilabel:`All Configurations` is selected
+ from the :guilabel:`Settings for:` dropdown list. Select the C/C++ tab. Choose
+ the General category in the popup menu at the top. Type the following text in
+ the entry box labeled :guilabel:`Additional Include Directories`::
+
+ ..\Include,..\PC
+
+ Then, choose the General category in the Linker tab, and enter ::
+
+ ..\PCbuild
+
+ in the text box labelled :guilabel:`Additional library Directories`.
+
+ Now you need to add some mode-specific settings:
+
+ Select :guilabel:`Release` in the :guilabel:`Configuration` dropdown list.
+ Choose the :guilabel:`Link` tab, choose the :guilabel:`Input` category, and
+ append ``pythonXY.lib`` to the list in the :guilabel:`Additional Dependencies`
+ box.
+
+ Select :guilabel:`Debug` in the :guilabel:`Configuration` dropdown list, and
+ append ``pythonXY_d.lib`` to the list in the :guilabel:`Additional Dependencies`
+ box. Then click the C/C++ tab, select :guilabel:`Code Generation`, and select
+ :guilabel:`Multi-threaded Debug DLL` from the :guilabel:`Runtime library`
+ dropdown list.
+
+ Select :guilabel:`Release` again from the :guilabel:`Configuration` dropdown
+ list. Select :guilabel:`Multi-threaded DLL` from the :guilabel:`Runtime
+ library` dropdown list.
+
+If your module creates a new type, you may have trouble with this line::
+
+ PyObject_HEAD_INIT(&PyType_Type)
+
+Change it to::
+
+ PyObject_HEAD_INIT(NULL)
+
+and add the following to the module initialization function::
+
+ MyObject_Type.ob_type = &PyType_Type;
+
+Refer to section 3 of the `Python FAQ <http://www.python.org/doc/FAQ.html>`_ for
+details on why you must do this.
+
+
+.. _dynamic-linking:
+
+Differences Between Unix and Windows
+====================================
+
+.. sectionauthor:: Chris Phoenix <cphoenix@best.com>
+
+
+Unix and Windows use completely different paradigms for run-time loading of
+code. Before you try to build a module that can be dynamically loaded, be aware
+of how your system works.
+
+In Unix, a shared object (:file:`.so`) file contains code to be used by the
+program, and also the names of functions and data that it expects to find in the
+program. When the file is joined to the program, all references to those
+functions and data in the file's code are changed to point to the actual
+locations in the program where the functions and data are placed in memory.
+This is basically a link operation.
+
+In Windows, a dynamic-link library (:file:`.dll`) file has no dangling
+references. Instead, an access to functions or data goes through a lookup
+table. So the DLL code does not have to be fixed up at runtime to refer to the
+program's memory; instead, the code already uses the DLL's lookup table, and the
+lookup table is modified at runtime to point to the functions and data.
+
+In Unix, there is only one type of library file (:file:`.a`) which contains code
+from several object files (:file:`.o`). During the link step to create a shared
+object file (:file:`.so`), the linker may find that it doesn't know where an
+identifier is defined. The linker will look for it in the object files in the
+libraries; if it finds it, it will include all the code from that object file.
+
+In Windows, there are two types of library, a static library and an import
+library (both called :file:`.lib`). A static library is like a Unix :file:`.a`
+file; it contains code to be included as necessary. An import library is
+basically used only to reassure the linker that a certain identifier is legal,
+and will be present in the program when the DLL is loaded. So the linker uses
+the information from the import library to build the lookup table for using
+identifiers that are not included in the DLL. When an application or a DLL is
+linked, an import library may be generated, which will need to be used for all
+future DLLs that depend on the symbols in the application or DLL.
+
+Suppose you are building two dynamic-load modules, B and C, which should share
+another block of code A. On Unix, you would *not* pass :file:`A.a` to the
+linker for :file:`B.so` and :file:`C.so`; that would cause it to be included
+twice, so that B and C would each have their own copy. In Windows, building
+:file:`A.dll` will also build :file:`A.lib`. You *do* pass :file:`A.lib` to the
+linker for B and C. :file:`A.lib` does not contain code; it just contains
+information which will be used at runtime to access A's code.
+
+In Windows, using an import library is sort of like using ``import spam``; it
+gives you access to spam's names, but does not create a separate copy. On Unix,
+linking with a library is more like ``from spam import *``; it does create a
+separate copy.
+
+
+.. _win-dlls:
+
+Using DLLs in Practice
+======================
+
+.. sectionauthor:: Chris Phoenix <cphoenix@best.com>
+
+
+Windows Python is built in Microsoft Visual C++; using other compilers may or
+may not work (though Borland seems to). The rest of this section is MSVC++
+specific.
+
+When creating DLLs in Windows, you must pass :file:`pythonXY.lib` to the linker.
+To build two DLLs, spam and ni (which uses C functions found in spam), you could
+use these commands::
+
+ cl /LD /I/python/include spam.c ../libs/pythonXY.lib
+ cl /LD /I/python/include ni.c spam.lib ../libs/pythonXY.lib
+
+The first command created three files: :file:`spam.obj`, :file:`spam.dll` and
+:file:`spam.lib`. :file:`Spam.dll` does not contain any Python functions (such
+as :cfunc:`PyArg_ParseTuple`), but it does know how to find the Python code
+thanks to :file:`pythonXY.lib`.
+
+The second command created :file:`ni.dll` (and :file:`.obj` and :file:`.lib`),
+which knows how to find the necessary functions from spam, and also from the
+Python executable.
+
+Not every identifier is exported to the lookup table. If you want any other
+modules (including Python) to be able to see your identifiers, you have to say
+``_declspec(dllexport)``, as in ``void _declspec(dllexport) initspam(void)`` or
+``PyObject _declspec(dllexport) *NiGetSpamData(void)``.
+
+Developer Studio will throw in a lot of import libraries that you do not really
+need, adding about 100K to your executable. To get rid of them, use the Project
+Settings dialog, Link tab, to specify *ignore default libraries*. Add the
+correct :file:`msvcrtxx.lib` to the list of libraries.
+
diff --git a/Doc/howto/advocacy.rst b/Doc/howto/advocacy.rst
new file mode 100644
index 0000000000..1f1754abc3
--- /dev/null
+++ b/Doc/howto/advocacy.rst
@@ -0,0 +1,356 @@
+*************************
+ Python Advocacy HOWTO
+*************************
+
+:Author: A.M. Kuchling
+:Release: 0.03
+
+
+.. topic:: Abstract
+
+ It's usually difficult to get your management to accept open source software,
+ and Python is no exception to this rule. This document discusses reasons to use
+ Python, strategies for winning acceptance, facts and arguments you can use, and
+ cases where you *shouldn't* try to use Python.
+
+
+Reasons to Use Python
+=====================
+
+There are several reasons to incorporate a scripting language into your
+development process, and this section will discuss them, and why Python has some
+properties that make it a particularly good choice.
+
+
+Programmability
+---------------
+
+Programs are often organized in a modular fashion. Lower-level operations are
+grouped together, and called by higher-level functions, which may in turn be
+used as basic operations by still further upper levels.
+
+For example, the lowest level might define a very low-level set of functions for
+accessing a hash table. The next level might use hash tables to store the
+headers of a mail message, mapping a header name like ``Date`` to a value such
+as ``Tue, 13 May 1997 20:00:54 -0400``. A yet higher level may operate on
+message objects, without knowing or caring that message headers are stored in a
+hash table, and so forth.
+
+Often, the lowest levels do very simple things; they implement a data structure
+such as a binary tree or hash table, or they perform some simple computation,
+such as converting a date string to a number. The higher levels then contain
+logic connecting these primitive operations. Using the approach, the primitives
+can be seen as basic building blocks which are then glued together to produce
+the complete product.
+
+Why is this design approach relevant to Python? Because Python is well suited
+to functioning as such a glue language. A common approach is to write a Python
+module that implements the lower level operations; for the sake of speed, the
+implementation might be in C, Java, or even Fortran. Once the primitives are
+available to Python programs, the logic underlying higher level operations is
+written in the form of Python code. The high-level logic is then more
+understandable, and easier to modify.
+
+John Ousterhout wrote a paper that explains this idea at greater length,
+entitled "Scripting: Higher Level Programming for the 21st Century". I
+recommend that you read this paper; see the references for the URL. Ousterhout
+is the inventor of the Tcl language, and therefore argues that Tcl should be
+used for this purpose; he only briefly refers to other languages such as Python,
+Perl, and Lisp/Scheme, but in reality, Ousterhout's argument applies to
+scripting languages in general, since you could equally write extensions for any
+of the languages mentioned above.
+
+
+Prototyping
+-----------
+
+In *The Mythical Man-Month*, Fredrick Brooks suggests the following rule when
+planning software projects: "Plan to throw one away; you will anyway." Brooks
+is saying that the first attempt at a software design often turns out to be
+wrong; unless the problem is very simple or you're an extremely good designer,
+you'll find that new requirements and features become apparent once development
+has actually started. If these new requirements can't be cleanly incorporated
+into the program's structure, you're presented with two unpleasant choices:
+hammer the new features into the program somehow, or scrap everything and write
+a new version of the program, taking the new features into account from the
+beginning.
+
+Python provides you with a good environment for quickly developing an initial
+prototype. That lets you get the overall program structure and logic right, and
+you can fine-tune small details in the fast development cycle that Python
+provides. Once you're satisfied with the GUI interface or program output, you
+can translate the Python code into C++, Fortran, Java, or some other compiled
+language.
+
+Prototyping means you have to be careful not to use too many Python features
+that are hard to implement in your other language. Using ``eval()``, or regular
+expressions, or the :mod:`pickle` module, means that you're going to need C or
+Java libraries for formula evaluation, regular expressions, and serialization,
+for example. But it's not hard to avoid such tricky code, and in the end the
+translation usually isn't very difficult. The resulting code can be rapidly
+debugged, because any serious logical errors will have been removed from the
+prototype, leaving only more minor slip-ups in the translation to track down.
+
+This strategy builds on the earlier discussion of programmability. Using Python
+as glue to connect lower-level components has obvious relevance for constructing
+prototype systems. In this way Python can help you with development, even if
+end users never come in contact with Python code at all. If the performance of
+the Python version is adequate and corporate politics allow it, you may not need
+to do a translation into C or Java, but it can still be faster to develop a
+prototype and then translate it, instead of attempting to produce the final
+version immediately.
+
+One example of this development strategy is Microsoft Merchant Server. Version
+1.0 was written in pure Python, by a company that subsequently was purchased by
+Microsoft. Version 2.0 began to translate the code into C++, shipping with some
+C++code and some Python code. Version 3.0 didn't contain any Python at all; all
+the code had been translated into C++. Even though the product doesn't contain
+a Python interpreter, the Python language has still served a useful purpose by
+speeding up development.
+
+This is a very common use for Python. Past conference papers have also
+described this approach for developing high-level numerical algorithms; see
+David M. Beazley and Peter S. Lomdahl's paper "Feeding a Large-scale Physics
+Application to Python" in the references for a good example. If an algorithm's
+basic operations are things like "Take the inverse of this 4000x4000 matrix",
+and are implemented in some lower-level language, then Python has almost no
+additional performance cost; the extra time required for Python to evaluate an
+expression like ``m.invert()`` is dwarfed by the cost of the actual computation.
+It's particularly good for applications where seemingly endless tweaking is
+required to get things right. GUI interfaces and Web sites are prime examples.
+
+The Python code is also shorter and faster to write (once you're familiar with
+Python), so it's easier to throw it away if you decide your approach was wrong;
+if you'd spent two weeks working on it instead of just two hours, you might
+waste time trying to patch up what you've got out of a natural reluctance to
+admit that those two weeks were wasted. Truthfully, those two weeks haven't
+been wasted, since you've learnt something about the problem and the technology
+you're using to solve it, but it's human nature to view this as a failure of
+some sort.
+
+
+Simplicity and Ease of Understanding
+------------------------------------
+
+Python is definitely *not* a toy language that's only usable for small tasks.
+The language features are general and powerful enough to enable it to be used
+for many different purposes. It's useful at the small end, for 10- or 20-line
+scripts, but it also scales up to larger systems that contain thousands of lines
+of code.
+
+However, this expressiveness doesn't come at the cost of an obscure or tricky
+syntax. While Python has some dark corners that can lead to obscure code, there
+are relatively few such corners, and proper design can isolate their use to only
+a few classes or modules. It's certainly possible to write confusing code by
+using too many features with too little concern for clarity, but most Python
+code can look a lot like a slightly-formalized version of human-understandable
+pseudocode.
+
+In *The New Hacker's Dictionary*, Eric S. Raymond gives the following definition
+for "compact":
+
+.. epigraph::
+
+ Compact *adj.* Of a design, describes the valuable property that it can all be
+ apprehended at once in one's head. This generally means the thing created from
+ the design can be used with greater facility and fewer errors than an equivalent
+ tool that is not compact. Compactness does not imply triviality or lack of
+ power; for example, C is compact and FORTRAN is not, but C is more powerful than
+ FORTRAN. Designs become non-compact through accreting features and cruft that
+ don't merge cleanly into the overall design scheme (thus, some fans of Classic C
+ maintain that ANSI C is no longer compact).
+
+ (From http://www.catb.org/ esr/jargon/html/C/compact.html)
+
+In this sense of the word, Python is quite compact, because the language has
+just a few ideas, which are used in lots of places. Take namespaces, for
+example. Import a module with ``import math``, and you create a new namespace
+called ``math``. Classes are also namespaces that share many of the properties
+of modules, and have a few of their own; for example, you can create instances
+of a class. Instances? They're yet another namespace. Namespaces are currently
+implemented as Python dictionaries, so they have the same methods as the
+standard dictionary data type: .keys() returns all the keys, and so forth.
+
+This simplicity arises from Python's development history. The language syntax
+derives from different sources; ABC, a relatively obscure teaching language, is
+one primary influence, and Modula-3 is another. (For more information about ABC
+and Modula-3, consult their respective Web sites at http://www.cwi.nl/
+steven/abc/ and http://www.m3.org.) Other features have come from C, Icon,
+Algol-68, and even Perl. Python hasn't really innovated very much, but instead
+has tried to keep the language small and easy to learn, building on ideas that
+have been tried in other languages and found useful.
+
+Simplicity is a virtue that should not be underestimated. It lets you learn the
+language more quickly, and then rapidly write code, code that often works the
+first time you run it.
+
+
+Java Integration
+----------------
+
+If you're working with Java, Jython (http://www.jython.org/) is definitely worth
+your attention. Jython is a re-implementation of Python in Java that compiles
+Python code into Java bytecodes. The resulting environment has very tight,
+almost seamless, integration with Java. It's trivial to access Java classes
+from Python, and you can write Python classes that subclass Java classes.
+Jython can be used for prototyping Java applications in much the same way
+CPython is used, and it can also be used for test suites for Java code, or
+embedded in a Java application to add scripting capabilities.
+
+
+Arguments and Rebuttals
+=======================
+
+Let's say that you've decided upon Python as the best choice for your
+application. How can you convince your management, or your fellow developers,
+to use Python? This section lists some common arguments against using Python,
+and provides some possible rebuttals.
+
+**Python is freely available software that doesn't cost anything. How good can
+it be?**
+
+Very good, indeed. These days Linux and Apache, two other pieces of open source
+software, are becoming more respected as alternatives to commercial software,
+but Python hasn't had all the publicity.
+
+Python has been around for several years, with many users and developers.
+Accordingly, the interpreter has been used by many people, and has gotten most
+of the bugs shaken out of it. While bugs are still discovered at intervals,
+they're usually either quite obscure (they'd have to be, for no one to have run
+into them before) or they involve interfaces to external libraries. The
+internals of the language itself are quite stable.
+
+Having the source code should be viewed as making the software available for
+peer review; people can examine the code, suggest (and implement) improvements,
+and track down bugs. To find out more about the idea of open source code, along
+with arguments and case studies supporting it, go to http://www.opensource.org.
+
+**Who's going to support it?**
+
+Python has a sizable community of developers, and the number is still growing.
+The Internet community surrounding the language is an active one, and is worth
+being considered another one of Python's advantages. Most questions posted to
+the comp.lang.python newsgroup are quickly answered by someone.
+
+Should you need to dig into the source code, you'll find it's clear and
+well-organized, so it's not very difficult to write extensions and track down
+bugs yourself. If you'd prefer to pay for support, there are companies and
+individuals who offer commercial support for Python.
+
+**Who uses Python for serious work?**
+
+Lots of people; one interesting thing about Python is the surprising diversity
+of applications that it's been used for. People are using Python to:
+
+* Run Web sites
+
+* Write GUI interfaces
+
+* Control number-crunching code on supercomputers
+
+* Make a commercial application scriptable by embedding the Python interpreter
+ inside it
+
+* Process large XML data sets
+
+* Build test suites for C or Java code
+
+Whatever your application domain is, there's probably someone who's used Python
+for something similar. Yet, despite being useable for such high-end
+applications, Python's still simple enough to use for little jobs.
+
+See http://wiki.python.org/moin/OrganizationsUsingPython for a list of some of
+the organizations that use Python.
+
+**What are the restrictions on Python's use?**
+
+They're practically nonexistent. Consult the :file:`Misc/COPYRIGHT` file in the
+source distribution, or http://www.python.org/doc/Copyright.html for the full
+language, but it boils down to three conditions.
+
+* You have to leave the copyright notice on the software; if you don't include
+ the source code in a product, you have to put the copyright notice in the
+ supporting documentation.
+
+* Don't claim that the institutions that have developed Python endorse your
+ product in any way.
+
+* If something goes wrong, you can't sue for damages. Practically all software
+ licences contain this condition.
+
+Notice that you don't have to provide source code for anything that contains
+Python or is built with it. Also, the Python interpreter and accompanying
+documentation can be modified and redistributed in any way you like, and you
+don't have to pay anyone any licensing fees at all.
+
+**Why should we use an obscure language like Python instead of well-known
+language X?**
+
+I hope this HOWTO, and the documents listed in the final section, will help
+convince you that Python isn't obscure, and has a healthily growing user base.
+One word of advice: always present Python's positive advantages, instead of
+concentrating on language X's failings. People want to know why a solution is
+good, rather than why all the other solutions are bad. So instead of attacking
+a competing solution on various grounds, simply show how Python's virtues can
+help.
+
+
+Useful Resources
+================
+
+http://www.pythonology.com/success
+ The Python Success Stories are a collection of stories from successful users of
+ Python, with the emphasis on business and corporate users.
+
+.. % \term{\url{http://www.fsbassociates.com/books/pythonchpt1.htm}}
+.. % The first chapter of \emph{Internet Programming with Python} also
+.. % examines some of the reasons for using Python. The book is well worth
+.. % buying, but the publishers have made the first chapter available on
+.. % the Web.
+
+http://home.pacbell.net/ouster/scripting.html
+ John Ousterhout's white paper on scripting is a good argument for the utility of
+ scripting languages, though naturally enough, he emphasizes Tcl, the language he
+ developed. Most of the arguments would apply to any scripting language.
+
+http://www.python.org/workshops/1997-10/proceedings/beazley.html
+ The authors, David M. Beazley and Peter S. Lomdahl, describe their use of
+ Python at Los Alamos National Laboratory. It's another good example of how
+ Python can help get real work done. This quotation from the paper has been
+ echoed by many people:
+
+ .. epigraph::
+
+ Originally developed as a large monolithic application for massively parallel
+ processing systems, we have used Python to transform our application into a
+ flexible, highly modular, and extremely powerful system for performing
+ simulation, data analysis, and visualization. In addition, we describe how
+ Python has solved a number of important problems related to the development,
+ debugging, deployment, and maintenance of scientific software.
+
+http://pythonjournal.cognizor.com/pyj1/Everitt-Feit_interview98-V1.html
+ This interview with Andy Feit, discussing Infoseek's use of Python, can be used
+ to show that choosing Python didn't introduce any difficulties into a company's
+ development process, and provided some substantial benefits.
+
+.. % \term{\url{http://www.python.org/psa/Commercial.html}}
+.. % Robin Friedrich wrote this document on how to support Python's use in
+.. % commercial projects.
+
+http://www.python.org/workshops/1997-10/proceedings/stein.ps
+ For the 6th Python conference, Greg Stein presented a paper that traced Python's
+ adoption and usage at a startup called eShop, and later at Microsoft.
+
+http://www.opensource.org
+ Management may be doubtful of the reliability and usefulness of software that
+ wasn't written commercially. This site presents arguments that show how open
+ source software can have considerable advantages over closed-source software.
+
+http://sunsite.unc.edu/LDP/HOWTO/mini/Advocacy.html
+ The Linux Advocacy mini-HOWTO was the inspiration for this document, and is also
+ well worth reading for general suggestions on winning acceptance for a new
+ technology, such as Linux or Python. In general, you won't make much progress
+ by simply attacking existing systems and complaining about their inadequacies;
+ this often ends up looking like unfocused whining. It's much better to point
+ out some of the many areas where Python is an improvement over other systems.
+
diff --git a/Doc/howto/curses.rst b/Doc/howto/curses.rst
new file mode 100644
index 0000000000..e16d07af3a
--- /dev/null
+++ b/Doc/howto/curses.rst
@@ -0,0 +1,434 @@
+**********************************
+ Curses Programming with Python
+**********************************
+
+:Author: A.M. Kuchling, Eric S. Raymond
+:Release: 2.02
+
+
+.. topic:: Abstract
+
+ This document describes how to write text-mode programs with Python 2.x, using
+ the :mod:`curses` extension module to control the display.
+
+
+What is curses?
+===============
+
+The curses library supplies a terminal-independent screen-painting and
+keyboard-handling facility for text-based terminals; such terminals include
+VT100s, the Linux console, and the simulated terminal provided by X11 programs
+such as xterm and rxvt. Display terminals support various control codes to
+perform common operations such as moving the cursor, scrolling the screen, and
+erasing areas. Different terminals use widely differing codes, and often have
+their own minor quirks.
+
+In a world of X displays, one might ask "why bother"? It's true that
+character-cell display terminals are an obsolete technology, but there are
+niches in which being able to do fancy things with them are still valuable. One
+is on small-footprint or embedded Unixes that don't carry an X server. Another
+is for tools like OS installers and kernel configurators that may have to run
+before X is available.
+
+The curses library hides all the details of different terminals, and provides
+the programmer with an abstraction of a display, containing multiple
+non-overlapping windows. The contents of a window can be changed in various
+ways-- adding text, erasing it, changing its appearance--and the curses library
+will automagically figure out what control codes need to be sent to the terminal
+to produce the right output.
+
+The curses library was originally written for BSD Unix; the later System V
+versions of Unix from AT&T added many enhancements and new functions. BSD curses
+is no longer maintained, having been replaced by ncurses, which is an
+open-source implementation of the AT&T interface. If you're using an
+open-source Unix such as Linux or FreeBSD, your system almost certainly uses
+ncurses. Since most current commercial Unix versions are based on System V
+code, all the functions described here will probably be available. The older
+versions of curses carried by some proprietary Unixes may not support
+everything, though.
+
+No one has made a Windows port of the curses module. On a Windows platform, try
+the Console module written by Fredrik Lundh. The Console module provides
+cursor-addressable text output, plus full support for mouse and keyboard input,
+and is available from http://effbot.org/efflib/console.
+
+
+The Python curses module
+------------------------
+
+Thy Python module is a fairly simple wrapper over the C functions provided by
+curses; if you're already familiar with curses programming in C, it's really
+easy to transfer that knowledge to Python. The biggest difference is that the
+Python interface makes things simpler, by merging different C functions such as
+:func:`addstr`, :func:`mvaddstr`, :func:`mvwaddstr`, into a single
+:meth:`addstr` method. You'll see this covered in more detail later.
+
+This HOWTO is simply an introduction to writing text-mode programs with curses
+and Python. It doesn't attempt to be a complete guide to the curses API; for
+that, see the Python library guide's section on ncurses, and the C manual pages
+for ncurses. It will, however, give you the basic ideas.
+
+
+Starting and ending a curses application
+========================================
+
+Before doing anything, curses must be initialized. This is done by calling the
+:func:`initscr` function, which will determine the terminal type, send any
+required setup codes to the terminal, and create various internal data
+structures. If successful, :func:`initscr` returns a window object representing
+the entire screen; this is usually called ``stdscr``, after the name of the
+corresponding C variable. ::
+
+ import curses
+ stdscr = curses.initscr()
+
+Usually curses applications turn off automatic echoing of keys to the screen, in
+order to be able to read keys and only display them under certain circumstances.
+This requires calling the :func:`noecho` function. ::
+
+ curses.noecho()
+
+Applications will also commonly need to react to keys instantly, without
+requiring the Enter key to be pressed; this is called cbreak mode, as opposed to
+the usual buffered input mode. ::
+
+ curses.cbreak()
+
+Terminals usually return special keys, such as the cursor keys or navigation
+keys such as Page Up and Home, as a multibyte escape sequence. While you could
+write your application to expect such sequences and process them accordingly,
+curses can do it for you, returning a special value such as
+:const:`curses.KEY_LEFT`. To get curses to do the job, you'll have to enable
+keypad mode. ::
+
+ stdscr.keypad(1)
+
+Terminating a curses application is much easier than starting one. You'll need
+to call ::
+
+ curses.nocbreak(); stdscr.keypad(0); curses.echo()
+
+to reverse the curses-friendly terminal settings. Then call the :func:`endwin`
+function to restore the terminal to its original operating mode. ::
+
+ curses.endwin()
+
+A common problem when debugging a curses application is to get your terminal
+messed up when the application dies without restoring the terminal to its
+previous state. In Python this commonly happens when your code is buggy and
+raises an uncaught exception. Keys are no longer be echoed to the screen when
+you type them, for example, which makes using the shell difficult.
+
+In Python you can avoid these complications and make debugging much easier by
+importing the module :mod:`curses.wrapper`. It supplies a :func:`wrapper`
+function that takes a callable. It does the initializations described above,
+and also initializes colors if color support is present. It then runs your
+provided callable and finally deinitializes appropriately. The callable is
+called inside a try-catch clause which catches exceptions, performs curses
+deinitialization, and then passes the exception upwards. Thus, your terminal
+won't be left in a funny state on exception.
+
+
+Windows and Pads
+================
+
+Windows are the basic abstraction in curses. A window object represents a
+rectangular area of the screen, and supports various methods to display text,
+erase it, allow the user to input strings, and so forth.
+
+The ``stdscr`` object returned by the :func:`initscr` function is a window
+object that covers the entire screen. Many programs may need only this single
+window, but you might wish to divide the screen into smaller windows, in order
+to redraw or clear them separately. The :func:`newwin` function creates a new
+window of a given size, returning the new window object. ::
+
+ begin_x = 20 ; begin_y = 7
+ height = 5 ; width = 40
+ win = curses.newwin(height, width, begin_y, begin_x)
+
+A word about the coordinate system used in curses: coordinates are always passed
+in the order *y,x*, and the top-left corner of a window is coordinate (0,0).
+This breaks a common convention for handling coordinates, where the *x*
+coordinate usually comes first. This is an unfortunate difference from most
+other computer applications, but it's been part of curses since it was first
+written, and it's too late to change things now.
+
+When you call a method to display or erase text, the effect doesn't immediately
+show up on the display. This is because curses was originally written with slow
+300-baud terminal connections in mind; with these terminals, minimizing the time
+required to redraw the screen is very important. This lets curses accumulate
+changes to the screen, and display them in the most efficient manner. For
+example, if your program displays some characters in a window, and then clears
+the window, there's no need to send the original characters because they'd never
+be visible.
+
+Accordingly, curses requires that you explicitly tell it to redraw windows,
+using the :func:`refresh` method of window objects. In practice, this doesn't
+really complicate programming with curses much. Most programs go into a flurry
+of activity, and then pause waiting for a keypress or some other action on the
+part of the user. All you have to do is to be sure that the screen has been
+redrawn before pausing to wait for user input, by simply calling
+``stdscr.refresh()`` or the :func:`refresh` method of some other relevant
+window.
+
+A pad is a special case of a window; it can be larger than the actual display
+screen, and only a portion of it displayed at a time. Creating a pad simply
+requires the pad's height and width, while refreshing a pad requires giving the
+coordinates of the on-screen area where a subsection of the pad will be
+displayed. ::
+
+ pad = curses.newpad(100, 100)
+ # These loops fill the pad with letters; this is
+ # explained in the next section
+ for y in range(0, 100):
+ for x in range(0, 100):
+ try: pad.addch(y,x, ord('a') + (x*x+y*y) % 26 )
+ except curses.error: pass
+
+ # Displays a section of the pad in the middle of the screen
+ pad.refresh( 0,0, 5,5, 20,75)
+
+The :func:`refresh` call displays a section of the pad in the rectangle
+extending from coordinate (5,5) to coordinate (20,75) on the screen; the upper
+left corner of the displayed section is coordinate (0,0) on the pad. Beyond
+that difference, pads are exactly like ordinary windows and support the same
+methods.
+
+If you have multiple windows and pads on screen there is a more efficient way to
+go, which will prevent annoying screen flicker at refresh time. Use the
+:meth:`noutrefresh` method of each window to update the data structure
+representing the desired state of the screen; then change the physical screen to
+match the desired state in one go with the function :func:`doupdate`. The
+normal :meth:`refresh` method calls :func:`doupdate` as its last act.
+
+
+Displaying Text
+===============
+
+From a C programmer's point of view, curses may sometimes look like a twisty
+maze of functions, all subtly different. For example, :func:`addstr` displays a
+string at the current cursor location in the ``stdscr`` window, while
+:func:`mvaddstr` moves to a given y,x coordinate first before displaying the
+string. :func:`waddstr` is just like :func:`addstr`, but allows specifying a
+window to use, instead of using ``stdscr`` by default. :func:`mvwaddstr` follows
+similarly.
+
+Fortunately the Python interface hides all these details; ``stdscr`` is a window
+object like any other, and methods like :func:`addstr` accept multiple argument
+forms. Usually there are four different forms.
+
++---------------------------------+-----------------------------------------------+
+| Form | Description |
++=================================+===============================================+
+| *str* or *ch* | Display the string *str* or character *ch* at |
+| | the current position |
++---------------------------------+-----------------------------------------------+
+| *str* or *ch*, *attr* | Display the string *str* or character *ch*, |
+| | using attribute *attr* at the current |
+| | position |
++---------------------------------+-----------------------------------------------+
+| *y*, *x*, *str* or *ch* | Move to position *y,x* within the window, and |
+| | display *str* or *ch* |
++---------------------------------+-----------------------------------------------+
+| *y*, *x*, *str* or *ch*, *attr* | Move to position *y,x* within the window, and |
+| | display *str* or *ch*, using attribute *attr* |
++---------------------------------+-----------------------------------------------+
+
+Attributes allow displaying text in highlighted forms, such as in boldface,
+underline, reverse code, or in color. They'll be explained in more detail in
+the next subsection.
+
+The :func:`addstr` function takes a Python string as the value to be displayed,
+while the :func:`addch` functions take a character, which can be either a Python
+string of length 1 or an integer. If it's a string, you're limited to
+displaying characters between 0 and 255. SVr4 curses provides constants for
+extension characters; these constants are integers greater than 255. For
+example, :const:`ACS_PLMINUS` is a +/- symbol, and :const:`ACS_ULCORNER` is the
+upper left corner of a box (handy for drawing borders).
+
+Windows remember where the cursor was left after the last operation, so if you
+leave out the *y,x* coordinates, the string or character will be displayed
+wherever the last operation left off. You can also move the cursor with the
+``move(y,x)`` method. Because some terminals always display a flashing cursor,
+you may want to ensure that the cursor is positioned in some location where it
+won't be distracting; it can be confusing to have the cursor blinking at some
+apparently random location.
+
+If your application doesn't need a blinking cursor at all, you can call
+``curs_set(0)`` to make it invisible. Equivalently, and for compatibility with
+older curses versions, there's a ``leaveok(bool)`` function. When *bool* is
+true, the curses library will attempt to suppress the flashing cursor, and you
+won't need to worry about leaving it in odd locations.
+
+
+Attributes and Color
+--------------------
+
+Characters can be displayed in different ways. Status lines in a text-based
+application are commonly shown in reverse video; a text viewer may need to
+highlight certain words. curses supports this by allowing you to specify an
+attribute for each cell on the screen.
+
+An attribute is a integer, each bit representing a different attribute. You can
+try to display text with multiple attribute bits set, but curses doesn't
+guarantee that all the possible combinations are available, or that they're all
+visually distinct. That depends on the ability of the terminal being used, so
+it's safest to stick to the most commonly available attributes, listed here.
+
++----------------------+--------------------------------------+
+| Attribute | Description |
++======================+======================================+
+| :const:`A_BLINK` | Blinking text |
++----------------------+--------------------------------------+
+| :const:`A_BOLD` | Extra bright or bold text |
++----------------------+--------------------------------------+
+| :const:`A_DIM` | Half bright text |
++----------------------+--------------------------------------+
+| :const:`A_REVERSE` | Reverse-video text |
++----------------------+--------------------------------------+
+| :const:`A_STANDOUT` | The best highlighting mode available |
++----------------------+--------------------------------------+
+| :const:`A_UNDERLINE` | Underlined text |
++----------------------+--------------------------------------+
+
+So, to display a reverse-video status line on the top line of the screen, you
+could code::
+
+ stdscr.addstr(0, 0, "Current mode: Typing mode",
+ curses.A_REVERSE)
+ stdscr.refresh()
+
+The curses library also supports color on those terminals that provide it, The
+most common such terminal is probably the Linux console, followed by color
+xterms.
+
+To use color, you must call the :func:`start_color` function soon after calling
+:func:`initscr`, to initialize the default color set (the
+:func:`curses.wrapper.wrapper` function does this automatically). Once that's
+done, the :func:`has_colors` function returns TRUE if the terminal in use can
+actually display color. (Note: curses uses the American spelling 'color',
+instead of the Canadian/British spelling 'colour'. If you're used to the
+British spelling, you'll have to resign yourself to misspelling it for the sake
+of these functions.)
+
+The curses library maintains a finite number of color pairs, containing a
+foreground (or text) color and a background color. You can get the attribute
+value corresponding to a color pair with the :func:`color_pair` function; this
+can be bitwise-OR'ed with other attributes such as :const:`A_REVERSE`, but
+again, such combinations are not guaranteed to work on all terminals.
+
+An example, which displays a line of text using color pair 1::
+
+ stdscr.addstr( "Pretty text", curses.color_pair(1) )
+ stdscr.refresh()
+
+As I said before, a color pair consists of a foreground and background color.
+:func:`start_color` initializes 8 basic colors when it activates color mode.
+They are: 0:black, 1:red, 2:green, 3:yellow, 4:blue, 5:magenta, 6:cyan, and
+7:white. The curses module defines named constants for each of these colors:
+:const:`curses.COLOR_BLACK`, :const:`curses.COLOR_RED`, and so forth.
+
+The ``init_pair(n, f, b)`` function changes the definition of color pair *n*, to
+foreground color f and background color b. Color pair 0 is hard-wired to white
+on black, and cannot be changed.
+
+Let's put all this together. To change color 1 to red text on a white
+background, you would call::
+
+ curses.init_pair(1, curses.COLOR_RED, curses.COLOR_WHITE)
+
+When you change a color pair, any text already displayed using that color pair
+will change to the new colors. You can also display new text in this color
+with::
+
+ stdscr.addstr(0,0, "RED ALERT!", curses.color_pair(1) )
+
+Very fancy terminals can change the definitions of the actual colors to a given
+RGB value. This lets you change color 1, which is usually red, to purple or
+blue or any other color you like. Unfortunately, the Linux console doesn't
+support this, so I'm unable to try it out, and can't provide any examples. You
+can check if your terminal can do this by calling :func:`can_change_color`,
+which returns TRUE if the capability is there. If you're lucky enough to have
+such a talented terminal, consult your system's man pages for more information.
+
+
+User Input
+==========
+
+The curses library itself offers only very simple input mechanisms. Python's
+support adds a text-input widget that makes up some of the lack.
+
+The most common way to get input to a window is to use its :meth:`getch` method.
+:meth:`getch` pauses and waits for the user to hit a key, displaying it if
+:func:`echo` has been called earlier. You can optionally specify a coordinate
+to which the cursor should be moved before pausing.
+
+It's possible to change this behavior with the method :meth:`nodelay`. After
+``nodelay(1)``, :meth:`getch` for the window becomes non-blocking and returns
+``curses.ERR`` (a value of -1) when no input is ready. There's also a
+:func:`halfdelay` function, which can be used to (in effect) set a timer on each
+:meth:`getch`; if no input becomes available within the number of milliseconds
+specified as the argument to :func:`halfdelay`, curses raises an exception.
+
+The :meth:`getch` method returns an integer; if it's between 0 and 255, it
+represents the ASCII code of the key pressed. Values greater than 255 are
+special keys such as Page Up, Home, or the cursor keys. You can compare the
+value returned to constants such as :const:`curses.KEY_PPAGE`,
+:const:`curses.KEY_HOME`, or :const:`curses.KEY_LEFT`. Usually the main loop of
+your program will look something like this::
+
+ while 1:
+ c = stdscr.getch()
+ if c == ord('p'): PrintDocument()
+ elif c == ord('q'): break # Exit the while()
+ elif c == curses.KEY_HOME: x = y = 0
+
+The :mod:`curses.ascii` module supplies ASCII class membership functions that
+take either integer or 1-character-string arguments; these may be useful in
+writing more readable tests for your command interpreters. It also supplies
+conversion functions that take either integer or 1-character-string arguments
+and return the same type. For example, :func:`curses.ascii.ctrl` returns the
+control character corresponding to its argument.
+
+There's also a method to retrieve an entire string, :const:`getstr()`. It isn't
+used very often, because its functionality is quite limited; the only editing
+keys available are the backspace key and the Enter key, which terminates the
+string. It can optionally be limited to a fixed number of characters. ::
+
+ curses.echo() # Enable echoing of characters
+
+ # Get a 15-character string, with the cursor on the top line
+ s = stdscr.getstr(0,0, 15)
+
+The Python :mod:`curses.textpad` module supplies something better. With it, you
+can turn a window into a text box that supports an Emacs-like set of
+keybindings. Various methods of :class:`Textbox` class support editing with
+input validation and gathering the edit results either with or without trailing
+spaces. See the library documentation on :mod:`curses.textpad` for the
+details.
+
+
+For More Information
+====================
+
+This HOWTO didn't cover some advanced topics, such as screen-scraping or
+capturing mouse events from an xterm instance. But the Python library page for
+the curses modules is now pretty complete. You should browse it next.
+
+If you're in doubt about the detailed behavior of any of the ncurses entry
+points, consult the manual pages for your curses implementation, whether it's
+ncurses or a proprietary Unix vendor's. The manual pages will document any
+quirks, and provide complete lists of all the functions, attributes, and
+:const:`ACS_\*` characters available to you.
+
+Because the curses API is so large, some functions aren't supported in the
+Python interface, not because they're difficult to implement, but because no one
+has needed them yet. Feel free to add them and then submit a patch. Also, we
+don't yet have support for the menus or panels libraries associated with
+ncurses; feel free to add that.
+
+If you write an interesting little program, feel free to contribute it as
+another demo. We can always use more of them!
+
+The ncurses FAQ: http://dickey.his.com/ncurses/ncurses.faq.html
+
diff --git a/Doc/howto/doanddont.rst b/Doc/howto/doanddont.rst
new file mode 100644
index 0000000000..a322c53570
--- /dev/null
+++ b/Doc/howto/doanddont.rst
@@ -0,0 +1,308 @@
+************************************
+ Idioms and Anti-Idioms in Python
+************************************
+
+:Author: Moshe Zadka
+
+This document is placed in the public doman.
+
+
+.. topic:: Abstract
+
+ This document can be considered a companion to the tutorial. It shows how to use
+ Python, and even more importantly, how *not* to use Python.
+
+
+Language Constructs You Should Not Use
+======================================
+
+While Python has relatively few gotchas compared to other languages, it still
+has some constructs which are only useful in corner cases, or are plain
+dangerous.
+
+
+from module import \*
+---------------------
+
+
+Inside Function Definitions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+``from module import *`` is *invalid* inside function definitions. While many
+versions of Python do not check for the invalidity, it does not make it more
+valid, no more then having a smart lawyer makes a man innocent. Do not use it
+like that ever. Even in versions where it was accepted, it made the function
+execution slower, because the compiler could not be certain which names are
+local and which are global. In Python 2.1 this construct causes warnings, and
+sometimes even errors.
+
+
+At Module Level
+^^^^^^^^^^^^^^^
+
+While it is valid to use ``from module import *`` at module level it is usually
+a bad idea. For one, this loses an important property Python otherwise has ---
+you can know where each toplevel name is defined by a simple "search" function
+in your favourite editor. You also open yourself to trouble in the future, if
+some module grows additional functions or classes.
+
+One of the most awful question asked on the newsgroup is why this code::
+
+ f = open("www")
+ f.read()
+
+does not work. Of course, it works just fine (assuming you have a file called
+"www".) But it does not work if somewhere in the module, the statement ``from os
+import *`` is present. The :mod:`os` module has a function called :func:`open`
+which returns an integer. While it is very useful, shadowing builtins is one of
+its least useful properties.
+
+Remember, you can never know for sure what names a module exports, so either
+take what you need --- ``from module import name1, name2``, or keep them in the
+module and access on a per-need basis --- ``import module;print module.name``.
+
+
+When It Is Just Fine
+^^^^^^^^^^^^^^^^^^^^
+
+There are situations in which ``from module import *`` is just fine:
+
+* The interactive prompt. For example, ``from math import *`` makes Python an
+ amazing scientific calculator.
+
+* When extending a module in C with a module in Python.
+
+* When the module advertises itself as ``from import *`` safe.
+
+
+Unadorned :keyword:`exec` and friends
+-------------------------------------
+
+The word "unadorned" refers to the use without an explicit dictionary, in which
+case those constructs evaluate code in the *current* environment. This is
+dangerous for the same reasons ``from import *`` is dangerous --- it might step
+over variables you are counting on and mess up things for the rest of your code.
+Simply do not do that.
+
+Bad examples::
+
+ >>> for name in sys.argv[1:]:
+ >>> exec "%s=1" % name
+ >>> def func(s, **kw):
+ >>> for var, val in kw.items():
+ >>> exec "s.%s=val" % var # invalid!
+ >>> exec(open("handler.py").read())
+ >>> handle()
+
+Good examples::
+
+ >>> d = {}
+ >>> for name in sys.argv[1:]:
+ >>> d[name] = 1
+ >>> def func(s, **kw):
+ >>> for var, val in kw.items():
+ >>> setattr(s, var, val)
+ >>> d={}
+ >>> exec(open("handle.py").read(), d, d)
+ >>> handle = d['handle']
+ >>> handle()
+
+
+from module import name1, name2
+-------------------------------
+
+This is a "don't" which is much weaker then the previous "don't"s but is still
+something you should not do if you don't have good reasons to do that. The
+reason it is usually bad idea is because you suddenly have an object which lives
+in two seperate namespaces. When the binding in one namespace changes, the
+binding in the other will not, so there will be a discrepancy between them. This
+happens when, for example, one module is reloaded, or changes the definition of
+a function at runtime.
+
+Bad example::
+
+ # foo.py
+ a = 1
+
+ # bar.py
+ from foo import a
+ if something():
+ a = 2 # danger: foo.a != a
+
+Good example::
+
+ # foo.py
+ a = 1
+
+ # bar.py
+ import foo
+ if something():
+ foo.a = 2
+
+
+except:
+-------
+
+Python has the ``except:`` clause, which catches all exceptions. Since *every*
+error in Python raises an exception, this makes many programming errors look
+like runtime problems, and hinders the debugging process.
+
+The following code shows a great example::
+
+ try:
+ foo = opne("file") # misspelled "open"
+ except:
+ sys.exit("could not open file!")
+
+The second line triggers a :exc:`NameError` which is caught by the except
+clause. The program will exit, and you will have no idea that this has nothing
+to do with the readability of ``"file"``.
+
+The example above is better written ::
+
+ try:
+ foo = opne("file") # will be changed to "open" as soon as we run it
+ except IOError:
+ sys.exit("could not open file")
+
+There are some situations in which the ``except:`` clause is useful: for
+example, in a framework when running callbacks, it is good not to let any
+callback disturb the framework.
+
+
+Exceptions
+==========
+
+Exceptions are a useful feature of Python. You should learn to raise them
+whenever something unexpected occurs, and catch them only where you can do
+something about them.
+
+The following is a very popular anti-idiom ::
+
+ def get_status(file):
+ if not os.path.exists(file):
+ print "file not found"
+ sys.exit(1)
+ return open(file).readline()
+
+Consider the case the file gets deleted between the time the call to
+:func:`os.path.exists` is made and the time :func:`open` is called. That means
+the last line will throw an :exc:`IOError`. The same would happen if *file*
+exists but has no read permission. Since testing this on a normal machine on
+existing and non-existing files make it seem bugless, that means in testing the
+results will seem fine, and the code will get shipped. Then an unhandled
+:exc:`IOError` escapes to the user, who has to watch the ugly traceback.
+
+Here is a better way to do it. ::
+
+ def get_status(file):
+ try:
+ return open(file).readline()
+ except (IOError, OSError):
+ print "file not found"
+ sys.exit(1)
+
+In this version, \*either\* the file gets opened and the line is read (so it
+works even on flaky NFS or SMB connections), or the message is printed and the
+application aborted.
+
+Still, :func:`get_status` makes too many assumptions --- that it will only be
+used in a short running script, and not, say, in a long running server. Sure,
+the caller could do something like ::
+
+ try:
+ status = get_status(log)
+ except SystemExit:
+ status = None
+
+So, try to make as few ``except`` clauses in your code --- those will usually be
+a catch-all in the :func:`main`, or inside calls which should always succeed.
+
+So, the best version is probably ::
+
+ def get_status(file):
+ return open(file).readline()
+
+The caller can deal with the exception if it wants (for example, if it tries
+several files in a loop), or just let the exception filter upwards to *its*
+caller.
+
+The last version is not very good either --- due to implementation details, the
+file would not be closed when an exception is raised until the handler finishes,
+and perhaps not at all in non-C implementations (e.g., Jython). ::
+
+ def get_status(file):
+ fp = open(file)
+ try:
+ return fp.readline()
+ finally:
+ fp.close()
+
+
+Using the Batteries
+===================
+
+Every so often, people seem to be writing stuff in the Python library again,
+usually poorly. While the occasional module has a poor interface, it is usually
+much better to use the rich standard library and data types that come with
+Python then inventing your own.
+
+A useful module very few people know about is :mod:`os.path`. It always has the
+correct path arithmetic for your operating system, and will usually be much
+better then whatever you come up with yourself.
+
+Compare::
+
+ # ugh!
+ return dir+"/"+file
+ # better
+ return os.path.join(dir, file)
+
+More useful functions in :mod:`os.path`: :func:`basename`, :func:`dirname` and
+:func:`splitext`.
+
+There are also many useful builtin functions people seem not to be aware of for
+some reason: :func:`min` and :func:`max` can find the minimum/maximum of any
+sequence with comparable semantics, for example, yet many people write their own
+:func:`max`/:func:`min`. Another highly useful function is :func:`reduce`. A
+classical use of :func:`reduce` is something like ::
+
+ import sys, operator
+ nums = map(float, sys.argv[1:])
+ print reduce(operator.add, nums)/len(nums)
+
+This cute little script prints the average of all numbers given on the command
+line. The :func:`reduce` adds up all the numbers, and the rest is just some
+pre- and postprocessing.
+
+On the same note, note that :func:`float`, :func:`int` and :func:`long` all
+accept arguments of type string, and so are suited to parsing --- assuming you
+are ready to deal with the :exc:`ValueError` they raise.
+
+
+Using Backslash to Continue Statements
+======================================
+
+Since Python treats a newline as a statement terminator, and since statements
+are often more then is comfortable to put in one line, many people do::
+
+ if foo.bar()['first'][0] == baz.quux(1, 2)[5:9] and \
+ calculate_number(10, 20) != forbulate(500, 360):
+ pass
+
+You should realize that this is dangerous: a stray space after the ``XXX`` would
+make this line wrong, and stray spaces are notoriously hard to see in editors.
+In this case, at least it would be a syntax error, but if the code was::
+
+ value = foo.bar()['first'][0]*baz.quux(1, 2)[5:9] \
+ + calculate_number(10, 20)*forbulate(500, 360)
+
+then it would just be subtly wrong.
+
+It is usually much better to use the implicit continuation inside parenthesis:
+
+This version is bulletproof::
+
+ value = (foo.bar()['first'][0]*baz.quux(1, 2)[5:9]
+ + calculate_number(10, 20)*forbulate(500, 360))
+
diff --git a/Doc/howto/functional.rst b/Doc/howto/functional.rst
new file mode 100644
index 0000000000..bc1279366b
--- /dev/null
+++ b/Doc/howto/functional.rst
@@ -0,0 +1,1400 @@
+********************************
+ Functional Programming HOWTO
+********************************
+
+:Author: \A. M. Kuchling
+:Release: 0.30
+
+(This is a first draft. Please send comments/error reports/suggestions to
+amk@amk.ca. This URL is probably not going to be the final location of the
+document, so be careful about linking to it -- you may want to add a
+disclaimer.)
+
+In this document, we'll take a tour of Python's features suitable for
+implementing programs in a functional style. After an introduction to the
+concepts of functional programming, we'll look at language features such as
+iterators and generators and relevant library modules such as :mod:`itertools`
+and :mod:`functools`.
+
+
+Introduction
+============
+
+This section explains the basic concept of functional programming; if you're
+just interested in learning about Python language features, skip to the next
+section.
+
+Programming languages support decomposing problems in several different ways:
+
+* Most programming languages are **procedural**: programs are lists of
+ instructions that tell the computer what to do with the program's input. C,
+ Pascal, and even Unix shells are procedural languages.
+
+* In **declarative** languages, you write a specification that describes the
+ problem to be solved, and the language implementation figures out how to
+ perform the computation efficiently. SQL is the declarative language you're
+ most likely to be familiar with; a SQL query describes the data set you want
+ to retrieve, and the SQL engine decides whether to scan tables or use indexes,
+ which subclauses should be performed first, etc.
+
+* **Object-oriented** programs manipulate collections of objects. Objects have
+ internal state and support methods that query or modify this internal state in
+ some way. Smalltalk and Java are object-oriented languages. C++ and Python
+ are languages that support object-oriented programming, but don't force the
+ use of object-oriented features.
+
+* **Functional** programming decomposes a problem into a set of functions.
+ Ideally, functions only take inputs and produce outputs, and don't have any
+ internal state that affects the output produced for a given input. Well-known
+ functional languages include the ML family (Standard ML, OCaml, and other
+ variants) and Haskell.
+
+The designers of some computer languages have chosen one approach to programming
+that's emphasized. This often makes it difficult to write programs that use a
+different approach. Other languages are multi-paradigm languages that support
+several different approaches. Lisp, C++, and Python are multi-paradigm; you can
+write programs or libraries that are largely procedural, object-oriented, or
+functional in all of these languages. In a large program, different sections
+might be written using different approaches; the GUI might be object-oriented
+while the processing logic is procedural or functional, for example.
+
+In a functional program, input flows through a set of functions. Each function
+operates on its input and produces some output. Functional style frowns upon
+functions with side effects that modify internal state or make other changes
+that aren't visible in the function's return value. Functions that have no side
+effects at all are called **purely functional**. Avoiding side effects means
+not using data structures that get updated as a program runs; every function's
+output must only depend on its input.
+
+Some languages are very strict about purity and don't even have assignment
+statements such as ``a=3`` or ``c = a + b``, but it's difficult to avoid all
+side effects. Printing to the screen or writing to a disk file are side
+effects, for example. For example, in Python a ``print`` statement or a
+``time.sleep(1)`` both return no useful value; they're only called for their
+side effects of sending some text to the screen or pausing execution for a
+second.
+
+Python programs written in functional style usually won't go to the extreme of
+avoiding all I/O or all assignments; instead, they'll provide a
+functional-appearing interface but will use non-functional features internally.
+For example, the implementation of a function will still use assignments to
+local variables, but won't modify global variables or have other side effects.
+
+Functional programming can be considered the opposite of object-oriented
+programming. Objects are little capsules containing some internal state along
+with a collection of method calls that let you modify this state, and programs
+consist of making the right set of state changes. Functional programming wants
+to avoid state changes as much as possible and works with data flowing between
+functions. In Python you might combine the two approaches by writing functions
+that take and return instances representing objects in your application (e-mail
+messages, transactions, etc.).
+
+Functional design may seem like an odd constraint to work under. Why should you
+avoid objects and side effects? There are theoretical and practical advantages
+to the functional style:
+
+* Formal provability.
+* Modularity.
+* Composability.
+* Ease of debugging and testing.
+
+Formal provability
+------------------
+
+A theoretical benefit is that it's easier to construct a mathematical proof that
+a functional program is correct.
+
+For a long time researchers have been interested in finding ways to
+mathematically prove programs correct. This is different from testing a program
+on numerous inputs and concluding that its output is usually correct, or reading
+a program's source code and concluding that the code looks right; the goal is
+instead a rigorous proof that a program produces the right result for all
+possible inputs.
+
+The technique used to prove programs correct is to write down **invariants**,
+properties of the input data and of the program's variables that are always
+true. For each line of code, you then show that if invariants X and Y are true
+**before** the line is executed, the slightly different invariants X' and Y' are
+true **after** the line is executed. This continues until you reach the end of
+the program, at which point the invariants should match the desired conditions
+on the program's output.
+
+Functional programming's avoidance of assignments arose because assignments are
+difficult to handle with this technique; assignments can break invariants that
+were true before the assignment without producing any new invariants that can be
+propagated onward.
+
+Unfortunately, proving programs correct is largely impractical and not relevant
+to Python software. Even trivial programs require proofs that are several pages
+long; the proof of correctness for a moderately complicated program would be
+enormous, and few or none of the programs you use daily (the Python interpreter,
+your XML parser, your web browser) could be proven correct. Even if you wrote
+down or generated a proof, there would then be the question of verifying the
+proof; maybe there's an error in it, and you wrongly believe you've proved the
+program correct.
+
+Modularity
+----------
+
+A more practical benefit of functional programming is that it forces you to
+break apart your problem into small pieces. Programs are more modular as a
+result. It's easier to specify and write a small function that does one thing
+than a large function that performs a complicated transformation. Small
+functions are also easier to read and to check for errors.
+
+
+Ease of debugging and testing
+-----------------------------
+
+Testing and debugging a functional-style program is easier.
+
+Debugging is simplified because functions are generally small and clearly
+specified. When a program doesn't work, each function is an interface point
+where you can check that the data are correct. You can look at the intermediate
+inputs and outputs to quickly isolate the function that's responsible for a bug.
+
+Testing is easier because each function is a potential subject for a unit test.
+Functions don't depend on system state that needs to be replicated before
+running a test; instead you only have to synthesize the right input and then
+check that the output matches expectations.
+
+
+
+Composability
+-------------
+
+As you work on a functional-style program, you'll write a number of functions
+with varying inputs and outputs. Some of these functions will be unavoidably
+specialized to a particular application, but others will be useful in a wide
+variety of programs. For example, a function that takes a directory path and
+returns all the XML files in the directory, or a function that takes a filename
+and returns its contents, can be applied to many different situations.
+
+Over time you'll form a personal library of utilities. Often you'll assemble
+new programs by arranging existing functions in a new configuration and writing
+a few functions specialized for the current task.
+
+
+
+Iterators
+=========
+
+I'll start by looking at a Python language feature that's an important
+foundation for writing functional-style programs: iterators.
+
+An iterator is an object representing a stream of data; this object returns the
+data one element at a time. A Python iterator must support a method called
+``next()`` that takes no arguments and always returns the next element of the
+stream. If there are no more elements in the stream, ``next()`` must raise the
+``StopIteration`` exception. Iterators don't have to be finite, though; it's
+perfectly reasonable to write an iterator that produces an infinite stream of
+data.
+
+The built-in :func:`iter` function takes an arbitrary object and tries to return
+an iterator that will return the object's contents or elements, raising
+:exc:`TypeError` if the object doesn't support iteration. Several of Python's
+built-in data types support iteration, the most common being lists and
+dictionaries. An object is called an **iterable** object if you can get an
+iterator for it.
+
+You can experiment with the iteration interface manually::
+
+ >>> L = [1,2,3]
+ >>> it = iter(L)
+ >>> print it
+ <iterator object at 0x8116870>
+ >>> it.next()
+ 1
+ >>> it.next()
+ 2
+ >>> it.next()
+ 3
+ >>> it.next()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ StopIteration
+ >>>
+
+Python expects iterable objects in several different contexts, the most
+important being the ``for`` statement. In the statement ``for X in Y``, Y must
+be an iterator or some object for which ``iter()`` can create an iterator.
+These two statements are equivalent::
+
+ for i in iter(obj):
+ print i
+
+ for i in obj:
+ print i
+
+Iterators can be materialized as lists or tuples by using the :func:`list` or
+:func:`tuple` constructor functions::
+
+ >>> L = [1,2,3]
+ >>> iterator = iter(L)
+ >>> t = tuple(iterator)
+ >>> t
+ (1, 2, 3)
+
+Sequence unpacking also supports iterators: if you know an iterator will return
+N elements, you can unpack them into an N-tuple::
+
+ >>> L = [1,2,3]
+ >>> iterator = iter(L)
+ >>> a,b,c = iterator
+ >>> a,b,c
+ (1, 2, 3)
+
+Built-in functions such as :func:`max` and :func:`min` can take a single
+iterator argument and will return the largest or smallest element. The ``"in"``
+and ``"not in"`` operators also support iterators: ``X in iterator`` is true if
+X is found in the stream returned by the iterator. You'll run into obvious
+problems if the iterator is infinite; ``max()``, ``min()``, and ``"not in"``
+will never return, and if the element X never appears in the stream, the
+``"in"`` operator won't return either.
+
+Note that you can only go forward in an iterator; there's no way to get the
+previous element, reset the iterator, or make a copy of it. Iterator objects
+can optionally provide these additional capabilities, but the iterator protocol
+only specifies the ``next()`` method. Functions may therefore consume all of
+the iterator's output, and if you need to do something different with the same
+stream, you'll have to create a new iterator.
+
+
+
+Data Types That Support Iterators
+---------------------------------
+
+We've already seen how lists and tuples support iterators. In fact, any Python
+sequence type, such as strings, will automatically support creation of an
+iterator.
+
+Calling :func:`iter` on a dictionary returns an iterator that will loop over the
+dictionary's keys::
+
+ >>> m = {'Jan': 1, 'Feb': 2, 'Mar': 3, 'Apr': 4, 'May': 5, 'Jun': 6,
+ ... 'Jul': 7, 'Aug': 8, 'Sep': 9, 'Oct': 10, 'Nov': 11, 'Dec': 12}
+ >>> for key in m:
+ ... print key, m[key]
+ Mar 3
+ Feb 2
+ Aug 8
+ Sep 9
+ May 5
+ Jun 6
+ Jul 7
+ Jan 1
+ Apr 4
+ Nov 11
+ Dec 12
+ Oct 10
+
+Note that the order is essentially random, because it's based on the hash
+ordering of the objects in the dictionary.
+
+Applying ``iter()`` to a dictionary always loops over the keys, but dictionaries
+have methods that return other iterators. If you want to iterate over keys,
+values, or key/value pairs, you can explicitly call the ``iterkeys()``,
+``itervalues()``, or ``iteritems()`` methods to get an appropriate iterator.
+
+The :func:`dict` constructor can accept an iterator that returns a finite stream
+of ``(key, value)`` tuples::
+
+ >>> L = [('Italy', 'Rome'), ('France', 'Paris'), ('US', 'Washington DC')]
+ >>> dict(iter(L))
+ {'Italy': 'Rome', 'US': 'Washington DC', 'France': 'Paris'}
+
+Files also support iteration by calling the ``readline()`` method until there
+are no more lines in the file. This means you can read each line of a file like
+this::
+
+ for line in file:
+ # do something for each line
+ ...
+
+Sets can take their contents from an iterable and let you iterate over the set's
+elements::
+
+ S = set((2, 3, 5, 7, 11, 13))
+ for i in S:
+ print i
+
+
+
+Generator expressions and list comprehensions
+=============================================
+
+Two common operations on an iterator's output are 1) performing some operation
+for every element, 2) selecting a subset of elements that meet some condition.
+For example, given a list of strings, you might want to strip off trailing
+whitespace from each line or extract all the strings containing a given
+substring.
+
+List comprehensions and generator expressions (short form: "listcomps" and
+"genexps") are a concise notation for such operations, borrowed from the
+functional programming language Haskell (http://www.haskell.org). You can strip
+all the whitespace from a stream of strings with the following code::
+
+ line_list = [' line 1\n', 'line 2 \n', ...]
+
+ # Generator expression -- returns iterator
+ stripped_iter = (line.strip() for line in line_list)
+
+ # List comprehension -- returns list
+ stripped_list = [line.strip() for line in line_list]
+
+You can select only certain elements by adding an ``"if"`` condition::
+
+ stripped_list = [line.strip() for line in line_list
+ if line != ""]
+
+With a list comprehension, you get back a Python list; ``stripped_list`` is a
+list containing the resulting lines, not an iterator. Generator expressions
+return an iterator that computes the values as necessary, not needing to
+materialize all the values at once. This means that list comprehensions aren't
+useful if you're working with iterators that return an infinite stream or a very
+large amount of data. Generator expressions are preferable in these situations.
+
+Generator expressions are surrounded by parentheses ("()") and list
+comprehensions are surrounded by square brackets ("[]"). Generator expressions
+have the form::
+
+ ( expression for expr in sequence1
+ if condition1
+ for expr2 in sequence2
+ if condition2
+ for expr3 in sequence3 ...
+ if condition3
+ for exprN in sequenceN
+ if conditionN )
+
+Again, for a list comprehension only the outside brackets are different (square
+brackets instead of parentheses).
+
+The elements of the generated output will be the successive values of
+``expression``. The ``if`` clauses are all optional; if present, ``expression``
+is only evaluated and added to the result when ``condition`` is true.
+
+Generator expressions always have to be written inside parentheses, but the
+parentheses signalling a function call also count. If you want to create an
+iterator that will be immediately passed to a function you can write::
+
+ obj_total = sum(obj.count for obj in list_all_objects())
+
+The ``for...in`` clauses contain the sequences to be iterated over. The
+sequences do not have to be the same length, because they are iterated over from
+left to right, **not** in parallel. For each element in ``sequence1``,
+``sequence2`` is looped over from the beginning. ``sequence3`` is then looped
+over for each resulting pair of elements from ``sequence1`` and ``sequence2``.
+
+To put it another way, a list comprehension or generator expression is
+equivalent to the following Python code::
+
+ for expr1 in sequence1:
+ if not (condition1):
+ continue # Skip this element
+ for expr2 in sequence2:
+ if not (condition2):
+ continue # Skip this element
+ ...
+ for exprN in sequenceN:
+ if not (conditionN):
+ continue # Skip this element
+
+ # Output the value of
+ # the expression.
+
+This means that when there are multiple ``for...in`` clauses but no ``if``
+clauses, the length of the resulting output will be equal to the product of the
+lengths of all the sequences. If you have two lists of length 3, the output
+list is 9 elements long::
+
+ seq1 = 'abc'
+ seq2 = (1,2,3)
+ >>> [ (x,y) for x in seq1 for y in seq2]
+ [('a', 1), ('a', 2), ('a', 3),
+ ('b', 1), ('b', 2), ('b', 3),
+ ('c', 1), ('c', 2), ('c', 3)]
+
+To avoid introducing an ambiguity into Python's grammar, if ``expression`` is
+creating a tuple, it must be surrounded with parentheses. The first list
+comprehension below is a syntax error, while the second one is correct::
+
+ # Syntax error
+ [ x,y for x in seq1 for y in seq2]
+ # Correct
+ [ (x,y) for x in seq1 for y in seq2]
+
+
+Generators
+==========
+
+Generators are a special class of functions that simplify the task of writing
+iterators. Regular functions compute a value and return it, but generators
+return an iterator that returns a stream of values.
+
+You're doubtless familiar with how regular function calls work in Python or C.
+When you call a function, it gets a private namespace where its local variables
+are created. When the function reaches a ``return`` statement, the local
+variables are destroyed and the value is returned to the caller. A later call
+to the same function creates a new private namespace and a fresh set of local
+variables. But, what if the local variables weren't thrown away on exiting a
+function? What if you could later resume the function where it left off? This
+is what generators provide; they can be thought of as resumable functions.
+
+Here's the simplest example of a generator function::
+
+ def generate_ints(N):
+ for i in range(N):
+ yield i
+
+Any function containing a ``yield`` keyword is a generator function; this is
+detected by Python's bytecode compiler which compiles the function specially as
+a result.
+
+When you call a generator function, it doesn't return a single value; instead it
+returns a generator object that supports the iterator protocol. On executing
+the ``yield`` expression, the generator outputs the value of ``i``, similar to a
+``return`` statement. The big difference between ``yield`` and a ``return``
+statement is that on reaching a ``yield`` the generator's state of execution is
+suspended and local variables are preserved. On the next call to the
+generator's ``.next()`` method, the function will resume executing.
+
+Here's a sample usage of the ``generate_ints()`` generator::
+
+ >>> gen = generate_ints(3)
+ >>> gen
+ <generator object at 0x8117f90>
+ >>> gen.next()
+ 0
+ >>> gen.next()
+ 1
+ >>> gen.next()
+ 2
+ >>> gen.next()
+ Traceback (most recent call last):
+ File "stdin", line 1, in ?
+ File "stdin", line 2, in generate_ints
+ StopIteration
+
+You could equally write ``for i in generate_ints(5)``, or ``a,b,c =
+generate_ints(3)``.
+
+Inside a generator function, the ``return`` statement can only be used without a
+value, and signals the end of the procession of values; after executing a
+``return`` the generator cannot return any further values. ``return`` with a
+value, such as ``return 5``, is a syntax error inside a generator function. The
+end of the generator's results can also be indicated by raising
+``StopIteration`` manually, or by just letting the flow of execution fall off
+the bottom of the function.
+
+You could achieve the effect of generators manually by writing your own class
+and storing all the local variables of the generator as instance variables. For
+example, returning a list of integers could be done by setting ``self.count`` to
+0, and having the ``next()`` method increment ``self.count`` and return it.
+However, for a moderately complicated generator, writing a corresponding class
+can be much messier.
+
+The test suite included with Python's library, ``test_generators.py``, contains
+a number of more interesting examples. Here's one generator that implements an
+in-order traversal of a tree using generators recursively.
+
+::
+
+ # A recursive generator that generates Tree leaves in in-order.
+ def inorder(t):
+ if t:
+ for x in inorder(t.left):
+ yield x
+
+ yield t.label
+
+ for x in inorder(t.right):
+ yield x
+
+Two other examples in ``test_generators.py`` produce solutions for the N-Queens
+problem (placing N queens on an NxN chess board so that no queen threatens
+another) and the Knight's Tour (finding a route that takes a knight to every
+square of an NxN chessboard without visiting any square twice).
+
+
+
+Passing values into a generator
+-------------------------------
+
+In Python 2.4 and earlier, generators only produced output. Once a generator's
+code was invoked to create an iterator, there was no way to pass any new
+information into the function when its execution is resumed. You could hack
+together this ability by making the generator look at a global variable or by
+passing in some mutable object that callers then modify, but these approaches
+are messy.
+
+In Python 2.5 there's a simple way to pass values into a generator.
+:keyword:`yield` became an expression, returning a value that can be assigned to
+a variable or otherwise operated on::
+
+ val = (yield i)
+
+I recommend that you **always** put parentheses around a ``yield`` expression
+when you're doing something with the returned value, as in the above example.
+The parentheses aren't always necessary, but it's easier to always add them
+instead of having to remember when they're needed.
+
+(PEP 342 explains the exact rules, which are that a ``yield``-expression must
+always be parenthesized except when it occurs at the top-level expression on the
+right-hand side of an assignment. This means you can write ``val = yield i``
+but have to use parentheses when there's an operation, as in ``val = (yield i)
++ 12``.)
+
+Values are sent into a generator by calling its ``send(value)`` method. This
+method resumes the generator's code and the ``yield`` expression returns the
+specified value. If the regular ``next()`` method is called, the ``yield``
+returns ``None``.
+
+Here's a simple counter that increments by 1 and allows changing the value of
+the internal counter.
+
+::
+
+ def counter (maximum):
+ i = 0
+ while i < maximum:
+ val = (yield i)
+ # If value provided, change counter
+ if val is not None:
+ i = val
+ else:
+ i += 1
+
+And here's an example of changing the counter:
+
+ >>> it = counter(10)
+ >>> print it.next()
+ 0
+ >>> print it.next()
+ 1
+ >>> print it.send(8)
+ 8
+ >>> print it.next()
+ 9
+ >>> print it.next()
+ Traceback (most recent call last):
+ File ``t.py'', line 15, in ?
+ print it.next()
+ StopIteration
+
+Because ``yield`` will often be returning ``None``, you should always check for
+this case. Don't just use its value in expressions unless you're sure that the
+``send()`` method will be the only method used resume your generator function.
+
+In addition to ``send()``, there are two other new methods on generators:
+
+* ``throw(type, value=None, traceback=None)`` is used to raise an exception
+ inside the generator; the exception is raised by the ``yield`` expression
+ where the generator's execution is paused.
+
+* ``close()`` raises a :exc:`GeneratorExit` exception inside the generator to
+ terminate the iteration. On receiving this exception, the generator's code
+ must either raise :exc:`GeneratorExit` or :exc:`StopIteration`; catching the
+ exception and doing anything else is illegal and will trigger a
+ :exc:`RuntimeError`. ``close()`` will also be called by Python's garbage
+ collector when the generator is garbage-collected.
+
+ If you need to run cleanup code when a :exc:`GeneratorExit` occurs, I suggest
+ using a ``try: ... finally:`` suite instead of catching :exc:`GeneratorExit`.
+
+The cumulative effect of these changes is to turn generators from one-way
+producers of information into both producers and consumers.
+
+Generators also become **coroutines**, a more generalized form of subroutines.
+Subroutines are entered at one point and exited at another point (the top of the
+function, and a ``return`` statement), but coroutines can be entered, exited,
+and resumed at many different points (the ``yield`` statements).
+
+
+Built-in functions
+==================
+
+Let's look in more detail at built-in functions often used with iterators.
+
+Two Python's built-in functions, :func:`map` and :func:`filter`, are somewhat
+obsolete; they duplicate the features of list comprehensions but return actual
+lists instead of iterators.
+
+``map(f, iterA, iterB, ...)`` returns a list containing ``f(iterA[0], iterB[0]),
+f(iterA[1], iterB[1]), f(iterA[2], iterB[2]), ...``.
+
+::
+
+ def upper(s):
+ return s.upper()
+ map(upper, ['sentence', 'fragment']) =>
+ ['SENTENCE', 'FRAGMENT']
+
+ [upper(s) for s in ['sentence', 'fragment']] =>
+ ['SENTENCE', 'FRAGMENT']
+
+As shown above, you can achieve the same effect with a list comprehension. The
+:func:`itertools.imap` function does the same thing but can handle infinite
+iterators; it'll be discussed later, in the section on the :mod:`itertools` module.
+
+``filter(predicate, iter)`` returns a list that contains all the sequence
+elements that meet a certain condition, and is similarly duplicated by list
+comprehensions. A **predicate** is a function that returns the truth value of
+some condition; for use with :func:`filter`, the predicate must take a single
+value.
+
+::
+
+ def is_even(x):
+ return (x % 2) == 0
+
+ filter(is_even, range(10)) =>
+ [0, 2, 4, 6, 8]
+
+This can also be written as a list comprehension::
+
+ >>> [x for x in range(10) if is_even(x)]
+ [0, 2, 4, 6, 8]
+
+:func:`filter` also has a counterpart in the :mod:`itertools` module,
+:func:`itertools.ifilter`, that returns an iterator and can therefore handle
+infinite sequences just as :func:`itertools.imap` can.
+
+``reduce(func, iter, [initial_value])`` doesn't have a counterpart in the
+:mod:`itertools` module because it cumulatively performs an operation on all the
+iterable's elements and therefore can't be applied to infinite iterables.
+``func`` must be a function that takes two elements and returns a single value.
+:func:`reduce` takes the first two elements A and B returned by the iterator and
+calculates ``func(A, B)``. It then requests the third element, C, calculates
+``func(func(A, B), C)``, combines this result with the fourth element returned,
+and continues until the iterable is exhausted. If the iterable returns no
+values at all, a :exc:`TypeError` exception is raised. If the initial value is
+supplied, it's used as a starting point and ``func(initial_value, A)`` is the
+first calculation.
+
+::
+
+ import operator
+ reduce(operator.concat, ['A', 'BB', 'C']) =>
+ 'ABBC'
+ reduce(operator.concat, []) =>
+ TypeError: reduce() of empty sequence with no initial value
+ reduce(operator.mul, [1,2,3], 1) =>
+ 6
+ reduce(operator.mul, [], 1) =>
+ 1
+
+If you use :func:`operator.add` with :func:`reduce`, you'll add up all the
+elements of the iterable. This case is so common that there's a special
+built-in called :func:`sum` to compute it::
+
+ reduce(operator.add, [1,2,3,4], 0) =>
+ 10
+ sum([1,2,3,4]) =>
+ 10
+ sum([]) =>
+ 0
+
+For many uses of :func:`reduce`, though, it can be clearer to just write the
+obvious :keyword:`for` loop::
+
+ # Instead of:
+ product = reduce(operator.mul, [1,2,3], 1)
+
+ # You can write:
+ product = 1
+ for i in [1,2,3]:
+ product *= i
+
+
+``enumerate(iter)`` counts off the elements in the iterable, returning 2-tuples
+containing the count and each element.
+
+::
+
+ enumerate(['subject', 'verb', 'object']) =>
+ (0, 'subject'), (1, 'verb'), (2, 'object')
+
+:func:`enumerate` is often used when looping through a list and recording the
+indexes at which certain conditions are met::
+
+ f = open('data.txt', 'r')
+ for i, line in enumerate(f):
+ if line.strip() == '':
+ print 'Blank line at line #%i' % i
+
+``sorted(iterable, [cmp=None], [key=None], [reverse=False)`` collects all the
+elements of the iterable into a list, sorts the list, and returns the sorted
+result. The ``cmp``, ``key``, and ``reverse`` arguments are passed through to
+the constructed list's ``.sort()`` method.
+
+::
+
+ import random
+ # Generate 8 random numbers between [0, 10000)
+ rand_list = random.sample(range(10000), 8)
+ rand_list =>
+ [769, 7953, 9828, 6431, 8442, 9878, 6213, 2207]
+ sorted(rand_list) =>
+ [769, 2207, 6213, 6431, 7953, 8442, 9828, 9878]
+ sorted(rand_list, reverse=True) =>
+ [9878, 9828, 8442, 7953, 6431, 6213, 2207, 769]
+
+(For a more detailed discussion of sorting, see the Sorting mini-HOWTO in the
+Python wiki at http://wiki.python.org/moin/HowTo/Sorting.)
+
+The ``any(iter)`` and ``all(iter)`` built-ins look at the truth values of an
+iterable's contents. :func:`any` returns True if any element in the iterable is
+a true value, and :func:`all` returns True if all of the elements are true
+values::
+
+ any([0,1,0]) =>
+ True
+ any([0,0,0]) =>
+ False
+ any([1,1,1]) =>
+ True
+ all([0,1,0]) =>
+ False
+ all([0,0,0]) =>
+ False
+ all([1,1,1]) =>
+ True
+
+
+Small functions and the lambda expression
+=========================================
+
+When writing functional-style programs, you'll often need little functions that
+act as predicates or that combine elements in some way.
+
+If there's a Python built-in or a module function that's suitable, you don't
+need to define a new function at all::
+
+ stripped_lines = [line.strip() for line in lines]
+ existing_files = filter(os.path.exists, file_list)
+
+If the function you need doesn't exist, you need to write it. One way to write
+small functions is to use the ``lambda`` statement. ``lambda`` takes a number
+of parameters and an expression combining these parameters, and creates a small
+function that returns the value of the expression::
+
+ lowercase = lambda x: x.lower()
+
+ print_assign = lambda name, value: name + '=' + str(value)
+
+ adder = lambda x, y: x+y
+
+An alternative is to just use the ``def`` statement and define a function in the
+usual way::
+
+ def lowercase(x):
+ return x.lower()
+
+ def print_assign(name, value):
+ return name + '=' + str(value)
+
+ def adder(x,y):
+ return x + y
+
+Which alternative is preferable? That's a style question; my usual course is to
+avoid using ``lambda``.
+
+One reason for my preference is that ``lambda`` is quite limited in the
+functions it can define. The result has to be computable as a single
+expression, which means you can't have multiway ``if... elif... else``
+comparisons or ``try... except`` statements. If you try to do too much in a
+``lambda`` statement, you'll end up with an overly complicated expression that's
+hard to read. Quick, what's the following code doing?
+
+::
+
+ total = reduce(lambda a, b: (0, a[1] + b[1]), items)[1]
+
+You can figure it out, but it takes time to disentangle the expression to figure
+out what's going on. Using a short nested ``def`` statements makes things a
+little bit better::
+
+ def combine (a, b):
+ return 0, a[1] + b[1]
+
+ total = reduce(combine, items)[1]
+
+But it would be best of all if I had simply used a ``for`` loop::
+
+ total = 0
+ for a, b in items:
+ total += b
+
+Or the :func:`sum` built-in and a generator expression::
+
+ total = sum(b for a,b in items)
+
+Many uses of :func:`reduce` are clearer when written as ``for`` loops.
+
+Fredrik Lundh once suggested the following set of rules for refactoring uses of
+``lambda``:
+
+1) Write a lambda function.
+2) Write a comment explaining what the heck that lambda does.
+3) Study the comment for a while, and think of a name that captures the essence
+ of the comment.
+4) Convert the lambda to a def statement, using that name.
+5) Remove the comment.
+
+I really like these rules, but you're free to disagree that this lambda-free
+style is better.
+
+
+The itertools module
+====================
+
+The :mod:`itertools` module contains a number of commonly-used iterators as well
+as functions for combining several iterators. This section will introduce the
+module's contents by showing small examples.
+
+The module's functions fall into a few broad classes:
+
+* Functions that create a new iterator based on an existing iterator.
+* Functions for treating an iterator's elements as function arguments.
+* Functions for selecting portions of an iterator's output.
+* A function for grouping an iterator's output.
+
+Creating new iterators
+----------------------
+
+``itertools.count(n)`` returns an infinite stream of integers, increasing by 1
+each time. You can optionally supply the starting number, which defaults to 0::
+
+ itertools.count() =>
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, ...
+ itertools.count(10) =>
+ 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, ...
+
+``itertools.cycle(iter)`` saves a copy of the contents of a provided iterable
+and returns a new iterator that returns its elements from first to last. The
+new iterator will repeat these elements infinitely.
+
+::
+
+ itertools.cycle([1,2,3,4,5]) =>
+ 1, 2, 3, 4, 5, 1, 2, 3, 4, 5, ...
+
+``itertools.repeat(elem, [n])`` returns the provided element ``n`` times, or
+returns the element endlessly if ``n`` is not provided.
+
+::
+
+ itertools.repeat('abc') =>
+ abc, abc, abc, abc, abc, abc, abc, abc, abc, abc, ...
+ itertools.repeat('abc', 5) =>
+ abc, abc, abc, abc, abc
+
+``itertools.chain(iterA, iterB, ...)`` takes an arbitrary number of iterables as
+input, and returns all the elements of the first iterator, then all the elements
+of the second, and so on, until all of the iterables have been exhausted.
+
+::
+
+ itertools.chain(['a', 'b', 'c'], (1, 2, 3)) =>
+ a, b, c, 1, 2, 3
+
+``itertools.izip(iterA, iterB, ...)`` takes one element from each iterable and
+returns them in a tuple::
+
+ itertools.izip(['a', 'b', 'c'], (1, 2, 3)) =>
+ ('a', 1), ('b', 2), ('c', 3)
+
+It's similiar to the built-in :func:`zip` function, but doesn't construct an
+in-memory list and exhaust all the input iterators before returning; instead
+tuples are constructed and returned only if they're requested. (The technical
+term for this behaviour is `lazy evaluation
+<http://en.wikipedia.org/wiki/Lazy_evaluation>`__.)
+
+This iterator is intended to be used with iterables that are all of the same
+length. If the iterables are of different lengths, the resulting stream will be
+the same length as the shortest iterable.
+
+::
+
+ itertools.izip(['a', 'b'], (1, 2, 3)) =>
+ ('a', 1), ('b', 2)
+
+You should avoid doing this, though, because an element may be taken from the
+longer iterators and discarded. This means you can't go on to use the iterators
+further because you risk skipping a discarded element.
+
+``itertools.islice(iter, [start], stop, [step])`` returns a stream that's a
+slice of the iterator. With a single ``stop`` argument, it will return the
+first ``stop`` elements. If you supply a starting index, you'll get
+``stop-start`` elements, and if you supply a value for ``step``, elements will
+be skipped accordingly. Unlike Python's string and list slicing, you can't use
+negative values for ``start``, ``stop``, or ``step``.
+
+::
+
+ itertools.islice(range(10), 8) =>
+ 0, 1, 2, 3, 4, 5, 6, 7
+ itertools.islice(range(10), 2, 8) =>
+ 2, 3, 4, 5, 6, 7
+ itertools.islice(range(10), 2, 8, 2) =>
+ 2, 4, 6
+
+``itertools.tee(iter, [n])`` replicates an iterator; it returns ``n``
+independent iterators that will all return the contents of the source iterator.
+If you don't supply a value for ``n``, the default is 2. Replicating iterators
+requires saving some of the contents of the source iterator, so this can consume
+significant memory if the iterator is large and one of the new iterators is
+consumed more than the others.
+
+::
+
+ itertools.tee( itertools.count() ) =>
+ iterA, iterB
+
+ where iterA ->
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, ...
+
+ and iterB ->
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, ...
+
+
+Calling functions on elements
+-----------------------------
+
+Two functions are used for calling other functions on the contents of an
+iterable.
+
+``itertools.imap(f, iterA, iterB, ...)`` returns a stream containing
+``f(iterA[0], iterB[0]), f(iterA[1], iterB[1]), f(iterA[2], iterB[2]), ...``::
+
+ itertools.imap(operator.add, [5, 6, 5], [1, 2, 3]) =>
+ 6, 8, 8
+
+The ``operator`` module contains a set of functions corresponding to Python's
+operators. Some examples are ``operator.add(a, b)`` (adds two values),
+``operator.ne(a, b)`` (same as ``a!=b``), and ``operator.attrgetter('id')``
+(returns a callable that fetches the ``"id"`` attribute).
+
+``itertools.starmap(func, iter)`` assumes that the iterable will return a stream
+of tuples, and calls ``f()`` using these tuples as the arguments::
+
+ itertools.starmap(os.path.join,
+ [('/usr', 'bin', 'java'), ('/bin', 'python'),
+ ('/usr', 'bin', 'perl'),('/usr', 'bin', 'ruby')])
+ =>
+ /usr/bin/java, /bin/python, /usr/bin/perl, /usr/bin/ruby
+
+
+Selecting elements
+------------------
+
+Another group of functions chooses a subset of an iterator's elements based on a
+predicate.
+
+``itertools.ifilter(predicate, iter)`` returns all the elements for which the
+predicate returns true::
+
+ def is_even(x):
+ return (x % 2) == 0
+
+ itertools.ifilter(is_even, itertools.count()) =>
+ 0, 2, 4, 6, 8, 10, 12, 14, ...
+
+``itertools.ifilterfalse(predicate, iter)`` is the opposite, returning all
+elements for which the predicate returns false::
+
+ itertools.ifilterfalse(is_even, itertools.count()) =>
+ 1, 3, 5, 7, 9, 11, 13, 15, ...
+
+``itertools.takewhile(predicate, iter)`` returns elements for as long as the
+predicate returns true. Once the predicate returns false, the iterator will
+signal the end of its results.
+
+::
+
+ def less_than_10(x):
+ return (x < 10)
+
+ itertools.takewhile(less_than_10, itertools.count()) =>
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
+
+ itertools.takewhile(is_even, itertools.count()) =>
+ 0
+
+``itertools.dropwhile(predicate, iter)`` discards elements while the predicate
+returns true, and then returns the rest of the iterable's results.
+
+::
+
+ itertools.dropwhile(less_than_10, itertools.count()) =>
+ 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, ...
+
+ itertools.dropwhile(is_even, itertools.count()) =>
+ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...
+
+
+Grouping elements
+-----------------
+
+The last function I'll discuss, ``itertools.groupby(iter, key_func=None)``, is
+the most complicated. ``key_func(elem)`` is a function that can compute a key
+value for each element returned by the iterable. If you don't supply a key
+function, the key is simply each element itself.
+
+``groupby()`` collects all the consecutive elements from the underlying iterable
+that have the same key value, and returns a stream of 2-tuples containing a key
+value and an iterator for the elements with that key.
+
+::
+
+ city_list = [('Decatur', 'AL'), ('Huntsville', 'AL'), ('Selma', 'AL'),
+ ('Anchorage', 'AK'), ('Nome', 'AK'),
+ ('Flagstaff', 'AZ'), ('Phoenix', 'AZ'), ('Tucson', 'AZ'),
+ ...
+ ]
+
+ def get_state ((city, state)):
+ return state
+
+ itertools.groupby(city_list, get_state) =>
+ ('AL', iterator-1),
+ ('AK', iterator-2),
+ ('AZ', iterator-3), ...
+
+ where
+ iterator-1 =>
+ ('Decatur', 'AL'), ('Huntsville', 'AL'), ('Selma', 'AL')
+ iterator-2 =>
+ ('Anchorage', 'AK'), ('Nome', 'AK')
+ iterator-3 =>
+ ('Flagstaff', 'AZ'), ('Phoenix', 'AZ'), ('Tucson', 'AZ')
+
+``groupby()`` assumes that the underlying iterable's contents will already be
+sorted based on the key. Note that the returned iterators also use the
+underlying iterable, so you have to consume the results of iterator-1 before
+requesting iterator-2 and its corresponding key.
+
+
+The functools module
+====================
+
+The :mod:`functools` module in Python 2.5 contains some higher-order functions.
+A **higher-order function** takes one or more functions as input and returns a
+new function. The most useful tool in this module is the
+:func:`functools.partial` function.
+
+For programs written in a functional style, you'll sometimes want to construct
+variants of existing functions that have some of the parameters filled in.
+Consider a Python function ``f(a, b, c)``; you may wish to create a new function
+``g(b, c)`` that's equivalent to ``f(1, b, c)``; you're filling in a value for
+one of ``f()``'s parameters. This is called "partial function application".
+
+The constructor for ``partial`` takes the arguments ``(function, arg1, arg2,
+... kwarg1=value1, kwarg2=value2)``. The resulting object is callable, so you
+can just call it to invoke ``function`` with the filled-in arguments.
+
+Here's a small but realistic example::
+
+ import functools
+
+ def log (message, subsystem):
+ "Write the contents of 'message' to the specified subsystem."
+ print '%s: %s' % (subsystem, message)
+ ...
+
+ server_log = functools.partial(log, subsystem='server')
+ server_log('Unable to open socket')
+
+
+The operator module
+-------------------
+
+The :mod:`operator` module was mentioned earlier. It contains a set of
+functions corresponding to Python's operators. These functions are often useful
+in functional-style code because they save you from writing trivial functions
+that perform a single operation.
+
+Some of the functions in this module are:
+
+* Math operations: ``add()``, ``sub()``, ``mul()``, ``div()``, ``floordiv()``,
+ ``abs()``, ...
+* Logical operations: ``not_()``, ``truth()``.
+* Bitwise operations: ``and_()``, ``or_()``, ``invert()``.
+* Comparisons: ``eq()``, ``ne()``, ``lt()``, ``le()``, ``gt()``, and ``ge()``.
+* Object identity: ``is_()``, ``is_not()``.
+
+Consult the operator module's documentation for a complete list.
+
+
+
+The functional module
+---------------------
+
+Collin Winter's `functional module <http://oakwinter.com/code/functional/>`__
+provides a number of more advanced tools for functional programming. It also
+reimplements several Python built-ins, trying to make them more intuitive to
+those used to functional programming in other languages.
+
+This section contains an introduction to some of the most important functions in
+``functional``; full documentation can be found at `the project's website
+<http://oakwinter.com/code/functional/documentation/>`__.
+
+``compose(outer, inner, unpack=False)``
+
+The ``compose()`` function implements function composition. In other words, it
+returns a wrapper around the ``outer`` and ``inner`` callables, such that the
+return value from ``inner`` is fed directly to ``outer``. That is,
+
+::
+
+ >>> def add(a, b):
+ ... return a + b
+ ...
+ >>> def double(a):
+ ... return 2 * a
+ ...
+ >>> compose(double, add)(5, 6)
+ 22
+
+is equivalent to
+
+::
+
+ >>> double(add(5, 6))
+ 22
+
+The ``unpack`` keyword is provided to work around the fact that Python functions
+are not always `fully curried <http://en.wikipedia.org/wiki/Currying>`__. By
+default, it is expected that the ``inner`` function will return a single object
+and that the ``outer`` function will take a single argument. Setting the
+``unpack`` argument causes ``compose`` to expect a tuple from ``inner`` which
+will be expanded before being passed to ``outer``. Put simply,
+
+::
+
+ compose(f, g)(5, 6)
+
+is equivalent to::
+
+ f(g(5, 6))
+
+while
+
+::
+
+ compose(f, g, unpack=True)(5, 6)
+
+is equivalent to::
+
+ f(*g(5, 6))
+
+Even though ``compose()`` only accepts two functions, it's trivial to build up a
+version that will compose any number of functions. We'll use ``reduce()``,
+``compose()`` and ``partial()`` (the last of which is provided by both
+``functional`` and ``functools``).
+
+::
+
+ from functional import compose, partial
+
+ multi_compose = partial(reduce, compose)
+
+
+We can also use ``map()``, ``compose()`` and ``partial()`` to craft a version of
+``"".join(...)`` that converts its arguments to string::
+
+ from functional import compose, partial
+
+ join = compose("".join, partial(map, str))
+
+
+``flip(func)``
+
+``flip()`` wraps the callable in ``func`` and causes it to receive its
+non-keyword arguments in reverse order.
+
+::
+
+ >>> def triple(a, b, c):
+ ... return (a, b, c)
+ ...
+ >>> triple(5, 6, 7)
+ (5, 6, 7)
+ >>>
+ >>> flipped_triple = flip(triple)
+ >>> flipped_triple(5, 6, 7)
+ (7, 6, 5)
+
+``foldl(func, start, iterable)``
+
+``foldl()`` takes a binary function, a starting value (usually some kind of
+'zero'), and an iterable. The function is applied to the starting value and the
+first element of the list, then the result of that and the second element of the
+list, then the result of that and the third element of the list, and so on.
+
+This means that a call such as::
+
+ foldl(f, 0, [1, 2, 3])
+
+is equivalent to::
+
+ f(f(f(0, 1), 2), 3)
+
+
+``foldl()`` is roughly equivalent to the following recursive function::
+
+ def foldl(func, start, seq):
+ if len(seq) == 0:
+ return start
+
+ return foldl(func, func(start, seq[0]), seq[1:])
+
+Speaking of equivalence, the above ``foldl`` call can be expressed in terms of
+the built-in ``reduce`` like so::
+
+ reduce(f, [1, 2, 3], 0)
+
+
+We can use ``foldl()``, ``operator.concat()`` and ``partial()`` to write a
+cleaner, more aesthetically-pleasing version of Python's ``"".join(...)``
+idiom::
+
+ from functional import foldl, partial
+ from operator import concat
+
+ join = partial(foldl, concat, "")
+
+
+Revision History and Acknowledgements
+=====================================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: Ian Bicking,
+Nick Coghlan, Nick Efford, Raymond Hettinger, Jim Jewett, Mike Krell, Leandro
+Lameiro, Jussi Salmela, Collin Winter, Blake Winton.
+
+Version 0.1: posted June 30 2006.
+
+Version 0.11: posted July 1 2006. Typo fixes.
+
+Version 0.2: posted July 10 2006. Merged genexp and listcomp sections into one.
+Typo fixes.
+
+Version 0.21: Added more references suggested on the tutor mailing list.
+
+Version 0.30: Adds a section on the ``functional`` module written by Collin
+Winter; adds short section on the operator module; a few other edits.
+
+
+References
+==========
+
+General
+-------
+
+**Structure and Interpretation of Computer Programs**, by Harold Abelson and
+Gerald Jay Sussman with Julie Sussman. Full text at
+http://mitpress.mit.edu/sicp/. In this classic textbook of computer science,
+chapters 2 and 3 discuss the use of sequences and streams to organize the data
+flow inside a program. The book uses Scheme for its examples, but many of the
+design approaches described in these chapters are applicable to functional-style
+Python code.
+
+http://www.defmacro.org/ramblings/fp.html: A general introduction to functional
+programming that uses Java examples and has a lengthy historical introduction.
+
+http://en.wikipedia.org/wiki/Functional_programming: General Wikipedia entry
+describing functional programming.
+
+http://en.wikipedia.org/wiki/Coroutine: Entry for coroutines.
+
+http://en.wikipedia.org/wiki/Currying: Entry for the concept of currying.
+
+Python-specific
+---------------
+
+http://gnosis.cx/TPiP/: The first chapter of David Mertz's book
+:title-reference:`Text Processing in Python` discusses functional programming
+for text processing, in the section titled "Utilizing Higher-Order Functions in
+Text Processing".
+
+Mertz also wrote a 3-part series of articles on functional programming
+for IBM's DeveloperWorks site; see
+`part 1 <http://www-128.ibm.com/developerworks/library/l-prog.html>`__,
+`part 2 <http://www-128.ibm.com/developerworks/library/l-prog2.html>`__, and
+`part 3 <http://www-128.ibm.com/developerworks/linux/library/l-prog3.html>`__,
+
+
+Python documentation
+--------------------
+
+Documentation for the :mod:`itertools` module.
+
+Documentation for the :mod:`operator` module.
+
+:pep:`289`: "Generator Expressions"
+
+:pep:`342`: "Coroutines via Enhanced Generators" describes the new generator
+features in Python 2.5.
+
+.. comment
+
+ Topics to place
+ -----------------------------
+
+ XXX os.walk()
+
+ XXX Need a large example.
+
+ But will an example add much? I'll post a first draft and see
+ what the comments say.
+
+.. comment
+
+ Original outline:
+ Introduction
+ Idea of FP
+ Programs built out of functions
+ Functions are strictly input-output, no internal state
+ Opposed to OO programming, where objects have state
+
+ Why FP?
+ Formal provability
+ Assignment is difficult to reason about
+ Not very relevant to Python
+ Modularity
+ Small functions that do one thing
+ Debuggability:
+ Easy to test due to lack of state
+ Easy to verify output from intermediate steps
+ Composability
+ You assemble a toolbox of functions that can be mixed
+
+ Tackling a problem
+ Need a significant example
+
+ Iterators
+ Generators
+ The itertools module
+ List comprehensions
+ Small functions and the lambda statement
+ Built-in functions
+ map
+ filter
+ reduce
+
+.. comment
+
+ Handy little function for printing part of an iterator -- used
+ while writing this document.
+
+ import itertools
+ def print_iter(it):
+ slice = itertools.islice(it, 10)
+ for elem in slice[:-1]:
+ sys.stdout.write(str(elem))
+ sys.stdout.write(', ')
+ print elem[-1]
+
+
diff --git a/Doc/howto/index.rst b/Doc/howto/index.rst
new file mode 100644
index 0000000000..e668856fae
--- /dev/null
+++ b/Doc/howto/index.rst
@@ -0,0 +1,25 @@
+***************
+ Python HOWTOs
+***************
+
+Python HOWTOs are documents that cover a single, specific topic,
+and attempt to cover it fairly completely. Modelled on the Linux
+Documentation Project's HOWTO collection, this collection is an
+effort to foster documentation that's more detailed than the
+Python Library Reference.
+
+Currently, the HOWTOs are:
+
+.. toctree::
+ :maxdepth: 1
+
+ advocacy.rst
+ pythonmac.rst
+ curses.rst
+ doanddont.rst
+ functional.rst
+ regex.rst
+ sockets.rst
+ unicode.rst
+ urllib2.rst
+
diff --git a/Doc/howto/pythonmac.rst b/Doc/howto/pythonmac.rst
new file mode 100644
index 0000000000..7811f374da
--- /dev/null
+++ b/Doc/howto/pythonmac.rst
@@ -0,0 +1,202 @@
+
+.. _using-on-mac:
+
+***************************
+Using Python on a Macintosh
+***************************
+
+:Author: Bob Savage <bobsavage@mac.com>
+
+
+Python on a Macintosh running Mac OS X is in principle very similar to Python on
+any other Unix platform, but there are a number of additional features such as
+the IDE and the Package Manager that are worth pointing out.
+
+The Mac-specific modules are documented in :ref:`mac-specific-services`.
+
+Python on Mac OS 9 or earlier can be quite different from Python on Unix or
+Windows, but is beyond the scope of this manual, as that platform is no longer
+supported, starting with Python 2.4. See http://www.cwi.nl/~jack/macpython for
+installers for the latest 2.3 release for Mac OS 9 and related documentation.
+
+
+.. _getting-osx:
+
+Getting and Installing MacPython
+================================
+
+Mac OS X 10.4 comes with Python 2.3 pre-installed by Apple. However, you are
+encouraged to install the most recent version of Python from the Python website
+(http://www.python.org). A "universal binary" build of Python 2.5, which runs
+natively on the Mac's new Intel and legacy PPC CPU's, is available there.
+
+What you get after installing is a number of things:
+
+* A :file:`MacPython 2.5` folder in your :file:`Applications` folder. In here
+ you find IDLE, the development environment that is a standard part of official
+ Python distributions; PythonLauncher, which handles double-clicking Python
+ scripts from the Finder; and the "Build Applet" tool, which allows you to
+ package Python scripts as standalone applications on your system.
+
+* A framework :file:`/Library/Frameworks/Python.framework`, which includes the
+ Python executable and libraries. The installer adds this location to your shell
+ path. To uninstall MacPython, you can simply remove these three things. A
+ symlink to the Python executable is placed in /usr/local/bin/.
+
+The Apple-provided build of Python is installed in
+:file:`/System/Library/Frameworks/Python.framework` and :file:`/usr/bin/python`,
+respectively. You should never modify or delete these, as they are
+Apple-controlled and are used by Apple- or third-party software.
+
+IDLE includes a help menu that allows you to access Python documentation. If you
+are completely new to Python you should start reading the tutorial introduction
+in that document.
+
+If you are familiar with Python on other Unix platforms you should read the
+section on running Python scripts from the Unix shell.
+
+
+How to run a Python script
+--------------------------
+
+Your best way to get started with Python on Mac OS X is through the IDLE
+integrated development environment, see section :ref:`ide` and use the Help menu
+when the IDE is running.
+
+If you want to run Python scripts from the Terminal window command line or from
+the Finder you first need an editor to create your script. Mac OS X comes with a
+number of standard Unix command line editors, :program:`vim` and
+:program:`emacs` among them. If you want a more Mac-like editor,
+:program:`BBEdit` or :program:`TextWrangler` from Bare Bones Software (see
+http://www.barebones.com/products/bbedit/index.shtml) are good choices, as is
+:program:`TextMate` (see http://macromates.com/). Other editors include
+:program:`Gvim` (http://macvim.org) and :program:`Aquamacs`
+(http://aquamacs.org).
+
+To run your script from the Terminal window you must make sure that
+:file:`/usr/local/bin` is in your shell search path.
+
+To run your script from the Finder you have two options:
+
+* Drag it to :program:`PythonLauncher`
+
+* Select :program:`PythonLauncher` as the default application to open your
+ script (or any .py script) through the finder Info window and double-click it.
+ :program:`PythonLauncher` has various preferences to control how your script is
+ launched. Option-dragging allows you to change these for one invocation, or use
+ its Preferences menu to change things globally.
+
+
+.. _osx-gui-scripts:
+
+Running scripts with a GUI
+--------------------------
+
+With older versions of Python, there is one Mac OS X quirk that you need to be
+aware of: programs that talk to the Aqua window manager (in other words,
+anything that has a GUI) need to be run in a special way. Use :program:`pythonw`
+instead of :program:`python` to start such scripts.
+
+With Python 2.5, you can use either :program:`python` or :program:`pythonw`.
+
+
+Configuration
+-------------
+
+Python on OS X honors all standard Unix environment variables such as
+:envvar:`PYTHONPATH`, but setting these variables for programs started from the
+Finder is non-standard as the Finder does not read your :file:`.profile` or
+:file:`.cshrc` at startup. You need to create a file :file:`~
+/.MacOSX/environment.plist`. See Apple's Technical Document QA1067 for details.
+
+For more information on installation Python packages in MacPython, see section
+:ref:`mac-package-manager`.
+
+
+.. _ide:
+
+The IDE
+=======
+
+MacPython ships with the standard IDLE development environment. A good
+introduction to using IDLE can be found at http://hkn.eecs.berkeley.edu/
+dyoo/python/idle_intro/index.html.
+
+
+.. _mac-package-manager:
+
+Installing Additional Python Packages
+=====================================
+
+There are several methods to install additional Python packages:
+
+* http://pythonmac.org/packages/ contains selected compiled packages for Python
+ 2.5, 2.4, and 2.3.
+
+* Packages can be installed via the standard Python distutils mode (``python
+ setup.py install``).
+
+* Many packages can also be installed via the :program:`setuptools` extension.
+
+
+GUI Programming on the Mac
+==========================
+
+There are several options for building GUI applications on the Mac with Python.
+
+*PyObjC* is a Python binding to Apple's Objective-C/Cocoa framework, which is
+the foundation of most modern Mac development. Information on PyObjC is
+available from http://pyobjc.sourceforge.net.
+
+The standard Python GUI toolkit is :mod:`Tkinter`, based on the cross-platform
+Tk toolkit (http://www.tcl.tk). An Aqua-native version of Tk is bundled with OS
+X by Apple, and the latest version can be downloaded and installed from
+http://www.activestate.com; it can also be built from source.
+
+*wxPython* is another popular cross-platform GUI toolkit that runs natively on
+Mac OS X. Packages and documentation are available from http://www.wxpython.org.
+
+*PyQt* is another popular cross-platform GUI toolkit that runs natively on Mac
+OS X. More information can be found at
+http://www.riverbankcomputing.co.uk/pyqt/.
+
+
+Distributing Python Applications on the Mac
+===========================================
+
+The "Build Applet" tool that is placed in the MacPython 2.5 folder is fine for
+packaging small Python scripts on your own machine to run as a standard Mac
+application. This tool, however, is not robust enough to distribute Python
+applications to other users.
+
+The standard tool for deploying standalone Python applications on the Mac is
+:program:`py2app`. More information on installing and using py2app can be found
+at http://undefined.org/python/#py2app.
+
+
+Application Scripting
+=====================
+
+Python can also be used to script other Mac applications via Apple's Open
+Scripting Architecture (OSA); see http://appscript.sourceforge.net. Appscript is
+a high-level, user-friendly Apple event bridge that allows you to control
+scriptable Mac OS X applications using ordinary Python scripts. Appscript makes
+Python a serious alternative to Apple's own *AppleScript* language for
+automating your Mac. A related package, *PyOSA*, is an OSA language component
+for the Python scripting language, allowing Python code to be executed by any
+OSA-enabled application (Script Editor, Mail, iTunes, etc.). PyOSA makes Python
+a full peer to AppleScript.
+
+
+Other Resources
+===============
+
+The MacPython mailing list is an excellent support resource for Python users and
+developers on the Mac:
+
+http://www.python.org/community/sigs/current/pythonmac-sig/
+
+Another useful resource is the MacPython wiki:
+
+http://wiki.python.org/moin/MacPython
+
diff --git a/Doc/howto/regex.rst b/Doc/howto/regex.rst
new file mode 100644
index 0000000000..b200764968
--- /dev/null
+++ b/Doc/howto/regex.rst
@@ -0,0 +1,1377 @@
+****************************
+ Regular Expression HOWTO
+****************************
+
+:Author: A.M. Kuchling
+:Release: 0.05
+
+.. % TODO:
+.. % Document lookbehind assertions
+.. % Better way of displaying a RE, a string, and what it matches
+.. % Mention optional argument to match.groups()
+.. % Unicode (at least a reference)
+
+
+.. topic:: Abstract
+
+ This document is an introductory tutorial to using regular expressions in Python
+ with the :mod:`re` module. It provides a gentler introduction than the
+ corresponding section in the Library Reference.
+
+
+Introduction
+============
+
+The :mod:`re` module was added in Python 1.5, and provides Perl-style regular
+expression patterns. Earlier versions of Python came with the :mod:`regex`
+module, which provided Emacs-style patterns. The :mod:`regex` module was
+removed completely in Python 2.5.
+
+Regular expressions (called REs, or regexes, or regex patterns) are essentially
+a tiny, highly specialized programming language embedded inside Python and made
+available through the :mod:`re` module. Using this little language, you specify
+the rules for the set of possible strings that you want to match; this set might
+contain English sentences, or e-mail addresses, or TeX commands, or anything you
+like. You can then ask questions such as "Does this string match the pattern?",
+or "Is there a match for the pattern anywhere in this string?". You can also
+use REs to modify a string or to split it apart in various ways.
+
+Regular expression patterns are compiled into a series of bytecodes which are
+then executed by a matching engine written in C. For advanced use, it may be
+necessary to pay careful attention to how the engine will execute a given RE,
+and write the RE in a certain way in order to produce bytecode that runs faster.
+Optimization isn't covered in this document, because it requires that you have a
+good understanding of the matching engine's internals.
+
+The regular expression language is relatively small and restricted, so not all
+possible string processing tasks can be done using regular expressions. There
+are also tasks that *can* be done with regular expressions, but the expressions
+turn out to be very complicated. In these cases, you may be better off writing
+Python code to do the processing; while Python code will be slower than an
+elaborate regular expression, it will also probably be more understandable.
+
+
+Simple Patterns
+===============
+
+We'll start by learning about the simplest possible regular expressions. Since
+regular expressions are used to operate on strings, we'll begin with the most
+common task: matching characters.
+
+For a detailed explanation of the computer science underlying regular
+expressions (deterministic and non-deterministic finite automata), you can refer
+to almost any textbook on writing compilers.
+
+
+Matching Characters
+-------------------
+
+Most letters and characters will simply match themselves. For example, the
+regular expression ``test`` will match the string ``test`` exactly. (You can
+enable a case-insensitive mode that would let this RE match ``Test`` or ``TEST``
+as well; more about this later.)
+
+There are exceptions to this rule; some characters are special
+:dfn:`metacharacters`, and don't match themselves. Instead, they signal that
+some out-of-the-ordinary thing should be matched, or they affect other portions
+of the RE by repeating them or changing their meaning. Much of this document is
+devoted to discussing various metacharacters and what they do.
+
+Here's a complete list of the metacharacters; their meanings will be discussed
+in the rest of this HOWTO. ::
+
+ . ^ $ * + ? { [ ] \ | ( )
+
+The first metacharacters we'll look at are ``[`` and ``]``. They're used for
+specifying a character class, which is a set of characters that you wish to
+match. Characters can be listed individually, or a range of characters can be
+indicated by giving two characters and separating them by a ``'-'``. For
+example, ``[abc]`` will match any of the characters ``a``, ``b``, or ``c``; this
+is the same as ``[a-c]``, which uses a range to express the same set of
+characters. If you wanted to match only lowercase letters, your RE would be
+``[a-z]``.
+
+.. % $
+
+Metacharacters are not active inside classes. For example, ``[akm$]`` will
+match any of the characters ``'a'``, ``'k'``, ``'m'``, or ``'$'``; ``'$'`` is
+usually a metacharacter, but inside a character class it's stripped of its
+special nature.
+
+You can match the characters not listed within the class by :dfn:`complementing`
+the set. This is indicated by including a ``'^'`` as the first character of the
+class; ``'^'`` outside a character class will simply match the ``'^'``
+character. For example, ``[^5]`` will match any character except ``'5'``.
+
+Perhaps the most important metacharacter is the backslash, ``\``. As in Python
+string literals, the backslash can be followed by various characters to signal
+various special sequences. It's also used to escape all the metacharacters so
+you can still match them in patterns; for example, if you need to match a ``[``
+or ``\``, you can precede them with a backslash to remove their special
+meaning: ``\[`` or ``\\``.
+
+Some of the special sequences beginning with ``'\'`` represent predefined sets
+of characters that are often useful, such as the set of digits, the set of
+letters, or the set of anything that isn't whitespace. The following predefined
+special sequences are available:
+
+``\d``
+ Matches any decimal digit; this is equivalent to the class ``[0-9]``.
+
+``\D``
+ Matches any non-digit character; this is equivalent to the class ``[^0-9]``.
+
+``\s``
+ Matches any whitespace character; this is equivalent to the class ``[
+ \t\n\r\f\v]``.
+
+``\S``
+ Matches any non-whitespace character; this is equivalent to the class ``[^
+ \t\n\r\f\v]``.
+
+``\w``
+ Matches any alphanumeric character; this is equivalent to the class
+ ``[a-zA-Z0-9_]``.
+
+``\W``
+ Matches any non-alphanumeric character; this is equivalent to the class
+ ``[^a-zA-Z0-9_]``.
+
+These sequences can be included inside a character class. For example,
+``[\s,.]`` is a character class that will match any whitespace character, or
+``','`` or ``'.'``.
+
+The final metacharacter in this section is ``.``. It matches anything except a
+newline character, and there's an alternate mode (``re.DOTALL``) where it will
+match even a newline. ``'.'`` is often used where you want to match "any
+character".
+
+
+Repeating Things
+----------------
+
+Being able to match varying sets of characters is the first thing regular
+expressions can do that isn't already possible with the methods available on
+strings. However, if that was the only additional capability of regexes, they
+wouldn't be much of an advance. Another capability is that you can specify that
+portions of the RE must be repeated a certain number of times.
+
+The first metacharacter for repeating things that we'll look at is ``*``. ``*``
+doesn't match the literal character ``*``; instead, it specifies that the
+previous character can be matched zero or more times, instead of exactly once.
+
+For example, ``ca*t`` will match ``ct`` (0 ``a`` characters), ``cat`` (1 ``a``),
+``caaat`` (3 ``a`` characters), and so forth. The RE engine has various
+internal limitations stemming from the size of C's ``int`` type that will
+prevent it from matching over 2 billion ``a`` characters; you probably don't
+have enough memory to construct a string that large, so you shouldn't run into
+that limit.
+
+Repetitions such as ``*`` are :dfn:`greedy`; when repeating a RE, the matching
+engine will try to repeat it as many times as possible. If later portions of the
+pattern don't match, the matching engine will then back up and try again with
+few repetitions.
+
+A step-by-step example will make this more obvious. Let's consider the
+expression ``a[bcd]*b``. This matches the letter ``'a'``, zero or more letters
+from the class ``[bcd]``, and finally ends with a ``'b'``. Now imagine matching
+this RE against the string ``abcbd``.
+
++------+-----------+---------------------------------+
+| Step | Matched | Explanation |
++======+===========+=================================+
+| 1 | ``a`` | The ``a`` in the RE matches. |
++------+-----------+---------------------------------+
+| 2 | ``abcbd`` | The engine matches ``[bcd]*``, |
+| | | going as far as it can, which |
+| | | is to the end of the string. |
++------+-----------+---------------------------------+
+| 3 | *Failure* | The engine tries to match |
+| | | ``b``, but the current position |
+| | | is at the end of the string, so |
+| | | it fails. |
++------+-----------+---------------------------------+
+| 4 | ``abcb`` | Back up, so that ``[bcd]*`` |
+| | | matches one less character. |
++------+-----------+---------------------------------+
+| 5 | *Failure* | Try ``b`` again, but the |
+| | | current position is at the last |
+| | | character, which is a ``'d'``. |
++------+-----------+---------------------------------+
+| 6 | ``abc`` | Back up again, so that |
+| | | ``[bcd]*`` is only matching |
+| | | ``bc``. |
++------+-----------+---------------------------------+
+| 6 | ``abcb`` | Try ``b`` again. This time |
+| | | but the character at the |
+| | | current position is ``'b'``, so |
+| | | it succeeds. |
++------+-----------+---------------------------------+
+
+The end of the RE has now been reached, and it has matched ``abcb``. This
+demonstrates how the matching engine goes as far as it can at first, and if no
+match is found it will then progressively back up and retry the rest of the RE
+again and again. It will back up until it has tried zero matches for
+``[bcd]*``, and if that subsequently fails, the engine will conclude that the
+string doesn't match the RE at all.
+
+Another repeating metacharacter is ``+``, which matches one or more times. Pay
+careful attention to the difference between ``*`` and ``+``; ``*`` matches
+*zero* or more times, so whatever's being repeated may not be present at all,
+while ``+`` requires at least *one* occurrence. To use a similar example,
+``ca+t`` will match ``cat`` (1 ``a``), ``caaat`` (3 ``a``'s), but won't match
+``ct``.
+
+There are two more repeating qualifiers. The question mark character, ``?``,
+matches either once or zero times; you can think of it as marking something as
+being optional. For example, ``home-?brew`` matches either ``homebrew`` or
+``home-brew``.
+
+The most complicated repeated qualifier is ``{m,n}``, where *m* and *n* are
+decimal integers. This qualifier means there must be at least *m* repetitions,
+and at most *n*. For example, ``a/{1,3}b`` will match ``a/b``, ``a//b``, and
+``a///b``. It won't match ``ab``, which has no slashes, or ``a////b``, which
+has four.
+
+You can omit either *m* or *n*; in that case, a reasonable value is assumed for
+the missing value. Omitting *m* is interpreted as a lower limit of 0, while
+omitting *n* results in an upper bound of infinity --- actually, the upper bound
+is the 2-billion limit mentioned earlier, but that might as well be infinity.
+
+Readers of a reductionist bent may notice that the three other qualifiers can
+all be expressed using this notation. ``{0,}`` is the same as ``*``, ``{1,}``
+is equivalent to ``+``, and ``{0,1}`` is the same as ``?``. It's better to use
+``*``, ``+``, or ``?`` when you can, simply because they're shorter and easier
+to read.
+
+
+Using Regular Expressions
+=========================
+
+Now that we've looked at some simple regular expressions, how do we actually use
+them in Python? The :mod:`re` module provides an interface to the regular
+expression engine, allowing you to compile REs into objects and then perform
+matches with them.
+
+
+Compiling Regular Expressions
+-----------------------------
+
+Regular expressions are compiled into :class:`RegexObject` instances, which have
+methods for various operations such as searching for pattern matches or
+performing string substitutions. ::
+
+ >>> import re
+ >>> p = re.compile('ab*')
+ >>> print p
+ <re.RegexObject instance at 80b4150>
+
+:func:`re.compile` also accepts an optional *flags* argument, used to enable
+various special features and syntax variations. We'll go over the available
+settings later, but for now a single example will do::
+
+ >>> p = re.compile('ab*', re.IGNORECASE)
+
+The RE is passed to :func:`re.compile` as a string. REs are handled as strings
+because regular expressions aren't part of the core Python language, and no
+special syntax was created for expressing them. (There are applications that
+don't need REs at all, so there's no need to bloat the language specification by
+including them.) Instead, the :mod:`re` module is simply a C extension module
+included with Python, just like the :mod:`socket` or :mod:`zlib` modules.
+
+Putting REs in strings keeps the Python language simpler, but has one
+disadvantage which is the topic of the next section.
+
+
+The Backslash Plague
+--------------------
+
+As stated earlier, regular expressions use the backslash character (``'\'``) to
+indicate special forms or to allow special characters to be used without
+invoking their special meaning. This conflicts with Python's usage of the same
+character for the same purpose in string literals.
+
+Let's say you want to write a RE that matches the string ``\section``, which
+might be found in a LaTeX file. To figure out what to write in the program
+code, start with the desired string to be matched. Next, you must escape any
+backslashes and other metacharacters by preceding them with a backslash,
+resulting in the string ``\\section``. The resulting string that must be passed
+to :func:`re.compile` must be ``\\section``. However, to express this as a
+Python string literal, both backslashes must be escaped *again*.
+
++-------------------+------------------------------------------+
+| Characters | Stage |
++===================+==========================================+
+| ``\section`` | Text string to be matched |
++-------------------+------------------------------------------+
+| ``\\section`` | Escaped backslash for :func:`re.compile` |
++-------------------+------------------------------------------+
+| ``"\\\\section"`` | Escaped backslashes for a string literal |
++-------------------+------------------------------------------+
+
+In short, to match a literal backslash, one has to write ``'\\\\'`` as the RE
+string, because the regular expression must be ``\\``, and each backslash must
+be expressed as ``\\`` inside a regular Python string literal. In REs that
+feature backslashes repeatedly, this leads to lots of repeated backslashes and
+makes the resulting strings difficult to understand.
+
+The solution is to use Python's raw string notation for regular expressions;
+backslashes are not handled in any special way in a string literal prefixed with
+``'r'``, so ``r"\n"`` is a two-character string containing ``'\'`` and ``'n'``,
+while ``"\n"`` is a one-character string containing a newline. Regular
+expressions will often be written in Python code using this raw string notation.
+
++-------------------+------------------+
+| Regular String | Raw string |
++===================+==================+
+| ``"ab*"`` | ``r"ab*"`` |
++-------------------+------------------+
+| ``"\\\\section"`` | ``r"\\section"`` |
++-------------------+------------------+
+| ``"\\w+\\s+\\1"`` | ``r"\w+\s+\1"`` |
++-------------------+------------------+
+
+
+Performing Matches
+------------------
+
+Once you have an object representing a compiled regular expression, what do you
+do with it? :class:`RegexObject` instances have several methods and attributes.
+Only the most significant ones will be covered here; consult `the Library
+Reference <http://www.python.org/doc/lib/module-re.html>`_ for a complete
+listing.
+
++------------------+-----------------------------------------------+
+| Method/Attribute | Purpose |
++==================+===============================================+
+| ``match()`` | Determine if the RE matches at the beginning |
+| | of the string. |
++------------------+-----------------------------------------------+
+| ``search()`` | Scan through a string, looking for any |
+| | location where this RE matches. |
++------------------+-----------------------------------------------+
+| ``findall()`` | Find all substrings where the RE matches, and |
+| | returns them as a list. |
++------------------+-----------------------------------------------+
+| ``finditer()`` | Find all substrings where the RE matches, and |
+| | returns them as an iterator. |
++------------------+-----------------------------------------------+
+
+:meth:`match` and :meth:`search` return ``None`` if no match can be found. If
+they're successful, a ``MatchObject`` instance is returned, containing
+information about the match: where it starts and ends, the substring it matched,
+and more.
+
+You can learn about this by interactively experimenting with the :mod:`re`
+module. If you have Tkinter available, you may also want to look at
+:file:`Tools/scripts/redemo.py`, a demonstration program included with the
+Python distribution. It allows you to enter REs and strings, and displays
+whether the RE matches or fails. :file:`redemo.py` can be quite useful when
+trying to debug a complicated RE. Phil Schwartz's `Kodos
+<http://www.phil-schwartz.com/kodos.spy>`_ is also an interactive tool for
+developing and testing RE patterns.
+
+This HOWTO uses the standard Python interpreter for its examples. First, run the
+Python interpreter, import the :mod:`re` module, and compile a RE::
+
+ Python 2.2.2 (#1, Feb 10 2003, 12:57:01)
+ >>> import re
+ >>> p = re.compile('[a-z]+')
+ >>> p
+ <_sre.SRE_Pattern object at 80c3c28>
+
+Now, you can try matching various strings against the RE ``[a-z]+``. An empty
+string shouldn't match at all, since ``+`` means 'one or more repetitions'.
+:meth:`match` should return ``None`` in this case, which will cause the
+interpreter to print no output. You can explicitly print the result of
+:meth:`match` to make this clear. ::
+
+ >>> p.match("")
+ >>> print p.match("")
+ None
+
+Now, let's try it on a string that it should match, such as ``tempo``. In this
+case, :meth:`match` will return a :class:`MatchObject`, so you should store the
+result in a variable for later use. ::
+
+ >>> m = p.match('tempo')
+ >>> print m
+ <_sre.SRE_Match object at 80c4f68>
+
+Now you can query the :class:`MatchObject` for information about the matching
+string. :class:`MatchObject` instances also have several methods and
+attributes; the most important ones are:
+
++------------------+--------------------------------------------+
+| Method/Attribute | Purpose |
++==================+============================================+
+| ``group()`` | Return the string matched by the RE |
++------------------+--------------------------------------------+
+| ``start()`` | Return the starting position of the match |
++------------------+--------------------------------------------+
+| ``end()`` | Return the ending position of the match |
++------------------+--------------------------------------------+
+| ``span()`` | Return a tuple containing the (start, end) |
+| | positions of the match |
++------------------+--------------------------------------------+
+
+Trying these methods will soon clarify their meaning::
+
+ >>> m.group()
+ 'tempo'
+ >>> m.start(), m.end()
+ (0, 5)
+ >>> m.span()
+ (0, 5)
+
+:meth:`group` returns the substring that was matched by the RE. :meth:`start`
+and :meth:`end` return the starting and ending index of the match. :meth:`span`
+returns both start and end indexes in a single tuple. Since the :meth:`match`
+method only checks if the RE matches at the start of a string, :meth:`start`
+will always be zero. However, the :meth:`search` method of :class:`RegexObject`
+instances scans through the string, so the match may not start at zero in that
+case. ::
+
+ >>> print p.match('::: message')
+ None
+ >>> m = p.search('::: message') ; print m
+ <re.MatchObject instance at 80c9650>
+ >>> m.group()
+ 'message'
+ >>> m.span()
+ (4, 11)
+
+In actual programs, the most common style is to store the :class:`MatchObject`
+in a variable, and then check if it was ``None``. This usually looks like::
+
+ p = re.compile( ... )
+ m = p.match( 'string goes here' )
+ if m:
+ print 'Match found: ', m.group()
+ else:
+ print 'No match'
+
+Two :class:`RegexObject` methods return all of the matches for a pattern.
+:meth:`findall` returns a list of matching strings::
+
+ >>> p = re.compile('\d+')
+ >>> p.findall('12 drummers drumming, 11 pipers piping, 10 lords a-leaping')
+ ['12', '11', '10']
+
+:meth:`findall` has to create the entire list before it can be returned as the
+result. The :meth:`finditer` method returns a sequence of :class:`MatchObject`
+instances as an iterator. [#]_ ::
+
+ >>> iterator = p.finditer('12 drummers drumming, 11 ... 10 ...')
+ >>> iterator
+ <callable-iterator object at 0x401833ac>
+ >>> for match in iterator:
+ ... print match.span()
+ ...
+ (0, 2)
+ (22, 24)
+ (29, 31)
+
+
+Module-Level Functions
+----------------------
+
+You don't have to create a :class:`RegexObject` and call its methods; the
+:mod:`re` module also provides top-level functions called :func:`match`,
+:func:`search`, :func:`findall`, :func:`sub`, and so forth. These functions
+take the same arguments as the corresponding :class:`RegexObject` method, with
+the RE string added as the first argument, and still return either ``None`` or a
+:class:`MatchObject` instance. ::
+
+ >>> print re.match(r'From\s+', 'Fromage amk')
+ None
+ >>> re.match(r'From\s+', 'From amk Thu May 14 19:12:10 1998')
+ <re.MatchObject instance at 80c5978>
+
+Under the hood, these functions simply produce a :class:`RegexObject` for you
+and call the appropriate method on it. They also store the compiled object in a
+cache, so future calls using the same RE are faster.
+
+Should you use these module-level functions, or should you get the
+:class:`RegexObject` and call its methods yourself? That choice depends on how
+frequently the RE will be used, and on your personal coding style. If the RE is
+being used at only one point in the code, then the module functions are probably
+more convenient. If a program contains a lot of regular expressions, or re-uses
+the same ones in several locations, then it might be worthwhile to collect all
+the definitions in one place, in a section of code that compiles all the REs
+ahead of time. To take an example from the standard library, here's an extract
+from :file:`xmllib.py`::
+
+ ref = re.compile( ... )
+ entityref = re.compile( ... )
+ charref = re.compile( ... )
+ starttagopen = re.compile( ... )
+
+I generally prefer to work with the compiled object, even for one-time uses, but
+few people will be as much of a purist about this as I am.
+
+
+Compilation Flags
+-----------------
+
+Compilation flags let you modify some aspects of how regular expressions work.
+Flags are available in the :mod:`re` module under two names, a long name such as
+:const:`IGNORECASE` and a short, one-letter form such as :const:`I`. (If you're
+familiar with Perl's pattern modifiers, the one-letter forms use the same
+letters; the short form of :const:`re.VERBOSE` is :const:`re.X`, for example.)
+Multiple flags can be specified by bitwise OR-ing them; ``re.I | re.M`` sets
+both the :const:`I` and :const:`M` flags, for example.
+
+Here's a table of the available flags, followed by a more detailed explanation
+of each one.
+
++---------------------------------+--------------------------------------------+
+| Flag | Meaning |
++=================================+============================================+
+| :const:`DOTALL`, :const:`S` | Make ``.`` match any character, including |
+| | newlines |
++---------------------------------+--------------------------------------------+
+| :const:`IGNORECASE`, :const:`I` | Do case-insensitive matches |
++---------------------------------+--------------------------------------------+
+| :const:`LOCALE`, :const:`L` | Do a locale-aware match |
++---------------------------------+--------------------------------------------+
+| :const:`MULTILINE`, :const:`M` | Multi-line matching, affecting ``^`` and |
+| | ``$`` |
++---------------------------------+--------------------------------------------+
+| :const:`VERBOSE`, :const:`X` | Enable verbose REs, which can be organized |
+| | more cleanly and understandably. |
++---------------------------------+--------------------------------------------+
+
+
+.. data:: I
+ IGNORECASE
+ :noindex:
+
+ Perform case-insensitive matching; character class and literal strings will
+ match letters by ignoring case. For example, ``[A-Z]`` will match lowercase
+ letters, too, and ``Spam`` will match ``Spam``, ``spam``, or ``spAM``. This
+ lowercasing doesn't take the current locale into account; it will if you also
+ set the :const:`LOCALE` flag.
+
+
+.. data:: L
+ LOCALE
+ :noindex:
+
+ Make ``\w``, ``\W``, ``\b``, and ``\B``, dependent on the current locale.
+
+ Locales are a feature of the C library intended to help in writing programs that
+ take account of language differences. For example, if you're processing French
+ text, you'd want to be able to write ``\w+`` to match words, but ``\w`` only
+ matches the character class ``[A-Za-z]``; it won't match ``'é'`` or ``'ç'``. If
+ your system is configured properly and a French locale is selected, certain C
+ functions will tell the program that ``'é'`` should also be considered a letter.
+ Setting the :const:`LOCALE` flag when compiling a regular expression will cause
+ the resulting compiled object to use these C functions for ``\w``; this is
+ slower, but also enables ``\w+`` to match French words as you'd expect.
+
+
+.. data:: M
+ MULTILINE
+ :noindex:
+
+ (``^`` and ``$`` haven't been explained yet; they'll be introduced in section
+ :ref:`more-metacharacters`.)
+
+ Usually ``^`` matches only at the beginning of the string, and ``$`` matches
+ only at the end of the string and immediately before the newline (if any) at the
+ end of the string. When this flag is specified, ``^`` matches at the beginning
+ of the string and at the beginning of each line within the string, immediately
+ following each newline. Similarly, the ``$`` metacharacter matches either at
+ the end of the string and at the end of each line (immediately preceding each
+ newline).
+
+
+.. data:: S
+ DOTALL
+ :noindex:
+
+ Makes the ``'.'`` special character match any character at all, including a
+ newline; without this flag, ``'.'`` will match anything *except* a newline.
+
+
+.. data:: X
+ VERBOSE
+ :noindex:
+
+ This flag allows you to write regular expressions that are more readable by
+ granting you more flexibility in how you can format them. When this flag has
+ been specified, whitespace within the RE string is ignored, except when the
+ whitespace is in a character class or preceded by an unescaped backslash; this
+ lets you organize and indent the RE more clearly. This flag also lets you put
+ comments within a RE that will be ignored by the engine; comments are marked by
+ a ``'#'`` that's neither in a character class or preceded by an unescaped
+ backslash.
+
+ For example, here's a RE that uses :const:`re.VERBOSE`; see how much easier it
+ is to read? ::
+
+ charref = re.compile(r"""
+ &[#] # Start of a numeric entity reference
+ (
+ 0[0-7]+ # Octal form
+ | [0-9]+ # Decimal form
+ | x[0-9a-fA-F]+ # Hexadecimal form
+ )
+ ; # Trailing semicolon
+ """, re.VERBOSE)
+
+ Without the verbose setting, the RE would look like this::
+
+ charref = re.compile("&#(0[0-7]+"
+ "|[0-9]+"
+ "|x[0-9a-fA-F]+);")
+
+ In the above example, Python's automatic concatenation of string literals has
+ been used to break up the RE into smaller pieces, but it's still more difficult
+ to understand than the version using :const:`re.VERBOSE`.
+
+
+More Pattern Power
+==================
+
+So far we've only covered a part of the features of regular expressions. In
+this section, we'll cover some new metacharacters, and how to use groups to
+retrieve portions of the text that was matched.
+
+
+.. _more-metacharacters:
+
+More Metacharacters
+-------------------
+
+There are some metacharacters that we haven't covered yet. Most of them will be
+covered in this section.
+
+Some of the remaining metacharacters to be discussed are :dfn:`zero-width
+assertions`. They don't cause the engine to advance through the string;
+instead, they consume no characters at all, and simply succeed or fail. For
+example, ``\b`` is an assertion that the current position is located at a word
+boundary; the position isn't changed by the ``\b`` at all. This means that
+zero-width assertions should never be repeated, because if they match once at a
+given location, they can obviously be matched an infinite number of times.
+
+``|``
+ Alternation, or the "or" operator. If A and B are regular expressions,
+ ``A|B`` will match any string that matches either ``A`` or ``B``. ``|`` has very
+ low precedence in order to make it work reasonably when you're alternating
+ multi-character strings. ``Crow|Servo`` will match either ``Crow`` or ``Servo``,
+ not ``Cro``, a ``'w'`` or an ``'S'``, and ``ervo``.
+
+ To match a literal ``'|'``, use ``\|``, or enclose it inside a character class,
+ as in ``[|]``.
+
+``^``
+ Matches at the beginning of lines. Unless the :const:`MULTILINE` flag has been
+ set, this will only match at the beginning of the string. In :const:`MULTILINE`
+ mode, this also matches immediately after each newline within the string.
+
+ For example, if you wish to match the word ``From`` only at the beginning of a
+ line, the RE to use is ``^From``. ::
+
+ >>> print re.search('^From', 'From Here to Eternity')
+ <re.MatchObject instance at 80c1520>
+ >>> print re.search('^From', 'Reciting From Memory')
+ None
+
+ .. % To match a literal \character{\^}, use \regexp{\e\^} or enclose it
+ .. % inside a character class, as in \regexp{[{\e}\^]}.
+
+``$``
+ Matches at the end of a line, which is defined as either the end of the string,
+ or any location followed by a newline character. ::
+
+ >>> print re.search('}$', '{block}')
+ <re.MatchObject instance at 80adfa8>
+ >>> print re.search('}$', '{block} ')
+ None
+ >>> print re.search('}$', '{block}\n')
+ <re.MatchObject instance at 80adfa8>
+
+ To match a literal ``'$'``, use ``\$`` or enclose it inside a character class,
+ as in ``[$]``.
+
+ .. % $
+
+``\A``
+ Matches only at the start of the string. When not in :const:`MULTILINE` mode,
+ ``\A`` and ``^`` are effectively the same. In :const:`MULTILINE` mode, they're
+ different: ``\A`` still matches only at the beginning of the string, but ``^``
+ may match at any location inside the string that follows a newline character.
+
+``\Z``
+ Matches only at the end of the string.
+
+``\b``
+ Word boundary. This is a zero-width assertion that matches only at the
+ beginning or end of a word. A word is defined as a sequence of alphanumeric
+ characters, so the end of a word is indicated by whitespace or a
+ non-alphanumeric character.
+
+ The following example matches ``class`` only when it's a complete word; it won't
+ match when it's contained inside another word. ::
+
+ >>> p = re.compile(r'\bclass\b')
+ >>> print p.search('no class at all')
+ <re.MatchObject instance at 80c8f28>
+ >>> print p.search('the declassified algorithm')
+ None
+ >>> print p.search('one subclass is')
+ None
+
+ There are two subtleties you should remember when using this special sequence.
+ First, this is the worst collision between Python's string literals and regular
+ expression sequences. In Python's string literals, ``\b`` is the backspace
+ character, ASCII value 8. If you're not using raw strings, then Python will
+ convert the ``\b`` to a backspace, and your RE won't match as you expect it to.
+ The following example looks the same as our previous RE, but omits the ``'r'``
+ in front of the RE string. ::
+
+ >>> p = re.compile('\bclass\b')
+ >>> print p.search('no class at all')
+ None
+ >>> print p.search('\b' + 'class' + '\b')
+ <re.MatchObject instance at 80c3ee0>
+
+ Second, inside a character class, where there's no use for this assertion,
+ ``\b`` represents the backspace character, for compatibility with Python's
+ string literals.
+
+``\B``
+ Another zero-width assertion, this is the opposite of ``\b``, only matching when
+ the current position is not at a word boundary.
+
+
+Grouping
+--------
+
+Frequently you need to obtain more information than just whether the RE matched
+or not. Regular expressions are often used to dissect strings by writing a RE
+divided into several subgroups which match different components of interest.
+For example, an RFC-822 header line is divided into a header name and a value,
+separated by a ``':'``, like this::
+
+ From: author@example.com
+ User-Agent: Thunderbird 1.5.0.9 (X11/20061227)
+ MIME-Version: 1.0
+ To: editor@example.com
+
+This can be handled by writing a regular expression which matches an entire
+header line, and has one group which matches the header name, and another group
+which matches the header's value.
+
+Groups are marked by the ``'('``, ``')'`` metacharacters. ``'('`` and ``')'``
+have much the same meaning as they do in mathematical expressions; they group
+together the expressions contained inside them, and you can repeat the contents
+of a group with a repeating qualifier, such as ``*``, ``+``, ``?``, or
+``{m,n}``. For example, ``(ab)*`` will match zero or more repetitions of
+``ab``. ::
+
+ >>> p = re.compile('(ab)*')
+ >>> print p.match('ababababab').span()
+ (0, 10)
+
+Groups indicated with ``'('``, ``')'`` also capture the starting and ending
+index of the text that they match; this can be retrieved by passing an argument
+to :meth:`group`, :meth:`start`, :meth:`end`, and :meth:`span`. Groups are
+numbered starting with 0. Group 0 is always present; it's the whole RE, so
+:class:`MatchObject` methods all have group 0 as their default argument. Later
+we'll see how to express groups that don't capture the span of text that they
+match. ::
+
+ >>> p = re.compile('(a)b')
+ >>> m = p.match('ab')
+ >>> m.group()
+ 'ab'
+ >>> m.group(0)
+ 'ab'
+
+Subgroups are numbered from left to right, from 1 upward. Groups can be nested;
+to determine the number, just count the opening parenthesis characters, going
+from left to right. ::
+
+ >>> p = re.compile('(a(b)c)d')
+ >>> m = p.match('abcd')
+ >>> m.group(0)
+ 'abcd'
+ >>> m.group(1)
+ 'abc'
+ >>> m.group(2)
+ 'b'
+
+:meth:`group` can be passed multiple group numbers at a time, in which case it
+will return a tuple containing the corresponding values for those groups. ::
+
+ >>> m.group(2,1,2)
+ ('b', 'abc', 'b')
+
+The :meth:`groups` method returns a tuple containing the strings for all the
+subgroups, from 1 up to however many there are. ::
+
+ >>> m.groups()
+ ('abc', 'b')
+
+Backreferences in a pattern allow you to specify that the contents of an earlier
+capturing group must also be found at the current location in the string. For
+example, ``\1`` will succeed if the exact contents of group 1 can be found at
+the current position, and fails otherwise. Remember that Python's string
+literals also use a backslash followed by numbers to allow including arbitrary
+characters in a string, so be sure to use a raw string when incorporating
+backreferences in a RE.
+
+For example, the following RE detects doubled words in a string. ::
+
+ >>> p = re.compile(r'(\b\w+)\s+\1')
+ >>> p.search('Paris in the the spring').group()
+ 'the the'
+
+Backreferences like this aren't often useful for just searching through a string
+--- there are few text formats which repeat data in this way --- but you'll soon
+find out that they're *very* useful when performing string substitutions.
+
+
+Non-capturing and Named Groups
+------------------------------
+
+Elaborate REs may use many groups, both to capture substrings of interest, and
+to group and structure the RE itself. In complex REs, it becomes difficult to
+keep track of the group numbers. There are two features which help with this
+problem. Both of them use a common syntax for regular expression extensions, so
+we'll look at that first.
+
+Perl 5 added several additional features to standard regular expressions, and
+the Python :mod:`re` module supports most of them. It would have been
+difficult to choose new single-keystroke metacharacters or new special sequences
+beginning with ``\`` to represent the new features without making Perl's regular
+expressions confusingly different from standard REs. If you chose ``&`` as a
+new metacharacter, for example, old expressions would be assuming that ``&`` was
+a regular character and wouldn't have escaped it by writing ``\&`` or ``[&]``.
+
+The solution chosen by the Perl developers was to use ``(?...)`` as the
+extension syntax. ``?`` immediately after a parenthesis was a syntax error
+because the ``?`` would have nothing to repeat, so this didn't introduce any
+compatibility problems. The characters immediately after the ``?`` indicate
+what extension is being used, so ``(?=foo)`` is one thing (a positive lookahead
+assertion) and ``(?:foo)`` is something else (a non-capturing group containing
+the subexpression ``foo``).
+
+Python adds an extension syntax to Perl's extension syntax. If the first
+character after the question mark is a ``P``, you know that it's an extension
+that's specific to Python. Currently there are two such extensions:
+``(?P<name>...)`` defines a named group, and ``(?P=name)`` is a backreference to
+a named group. If future versions of Perl 5 add similar features using a
+different syntax, the :mod:`re` module will be changed to support the new
+syntax, while preserving the Python-specific syntax for compatibility's sake.
+
+Now that we've looked at the general extension syntax, we can return to the
+features that simplify working with groups in complex REs. Since groups are
+numbered from left to right and a complex expression may use many groups, it can
+become difficult to keep track of the correct numbering. Modifying such a
+complex RE is annoying, too: insert a new group near the beginning and you
+change the numbers of everything that follows it.
+
+Sometimes you'll want to use a group to collect a part of a regular expression,
+but aren't interested in retrieving the group's contents. You can make this fact
+explicit by using a non-capturing group: ``(?:...)``, where you can replace the
+``...`` with any other regular expression. ::
+
+ >>> m = re.match("([abc])+", "abc")
+ >>> m.groups()
+ ('c',)
+ >>> m = re.match("(?:[abc])+", "abc")
+ >>> m.groups()
+ ()
+
+Except for the fact that you can't retrieve the contents of what the group
+matched, a non-capturing group behaves exactly the same as a capturing group;
+you can put anything inside it, repeat it with a repetition metacharacter such
+as ``*``, and nest it within other groups (capturing or non-capturing).
+``(?:...)`` is particularly useful when modifying an existing pattern, since you
+can add new groups without changing how all the other groups are numbered. It
+should be mentioned that there's no performance difference in searching between
+capturing and non-capturing groups; neither form is any faster than the other.
+
+A more significant feature is named groups: instead of referring to them by
+numbers, groups can be referenced by a name.
+
+The syntax for a named group is one of the Python-specific extensions:
+``(?P<name>...)``. *name* is, obviously, the name of the group. Named groups
+also behave exactly like capturing groups, and additionally associate a name
+with a group. The :class:`MatchObject` methods that deal with capturing groups
+all accept either integers that refer to the group by number or strings that
+contain the desired group's name. Named groups are still given numbers, so you
+can retrieve information about a group in two ways::
+
+ >>> p = re.compile(r'(?P<word>\b\w+\b)')
+ >>> m = p.search( '(((( Lots of punctuation )))' )
+ >>> m.group('word')
+ 'Lots'
+ >>> m.group(1)
+ 'Lots'
+
+Named groups are handy because they let you use easily-remembered names, instead
+of having to remember numbers. Here's an example RE from the :mod:`imaplib`
+module::
+
+ InternalDate = re.compile(r'INTERNALDATE "'
+ r'(?P<day>[ 123][0-9])-(?P<mon>[A-Z][a-z][a-z])-'
+ r'(?P<year>[0-9][0-9][0-9][0-9])'
+ r' (?P<hour>[0-9][0-9]):(?P<min>[0-9][0-9]):(?P<sec>[0-9][0-9])'
+ r' (?P<zonen>[-+])(?P<zoneh>[0-9][0-9])(?P<zonem>[0-9][0-9])'
+ r'"')
+
+It's obviously much easier to retrieve ``m.group('zonem')``, instead of having
+to remember to retrieve group 9.
+
+The syntax for backreferences in an expression such as ``(...)\1`` refers to the
+number of the group. There's naturally a variant that uses the group name
+instead of the number. This is another Python extension: ``(?P=name)`` indicates
+that the contents of the group called *name* should again be matched at the
+current point. The regular expression for finding doubled words,
+``(\b\w+)\s+\1`` can also be written as ``(?P<word>\b\w+)\s+(?P=word)``::
+
+ >>> p = re.compile(r'(?P<word>\b\w+)\s+(?P=word)')
+ >>> p.search('Paris in the the spring').group()
+ 'the the'
+
+
+Lookahead Assertions
+--------------------
+
+Another zero-width assertion is the lookahead assertion. Lookahead assertions
+are available in both positive and negative form, and look like this:
+
+``(?=...)``
+ Positive lookahead assertion. This succeeds if the contained regular
+ expression, represented here by ``...``, successfully matches at the current
+ location, and fails otherwise. But, once the contained expression has been
+ tried, the matching engine doesn't advance at all; the rest of the pattern is
+ tried right where the assertion started.
+
+``(?!...)``
+ Negative lookahead assertion. This is the opposite of the positive assertion;
+ it succeeds if the contained expression *doesn't* match at the current position
+ in the string.
+
+To make this concrete, let's look at a case where a lookahead is useful.
+Consider a simple pattern to match a filename and split it apart into a base
+name and an extension, separated by a ``.``. For example, in ``news.rc``,
+``news`` is the base name, and ``rc`` is the filename's extension.
+
+The pattern to match this is quite simple:
+
+``.*[.].*$``
+
+Notice that the ``.`` needs to be treated specially because it's a
+metacharacter; I've put it inside a character class. Also notice the trailing
+``$``; this is added to ensure that all the rest of the string must be included
+in the extension. This regular expression matches ``foo.bar`` and
+``autoexec.bat`` and ``sendmail.cf`` and ``printers.conf``.
+
+Now, consider complicating the problem a bit; what if you want to match
+filenames where the extension is not ``bat``? Some incorrect attempts:
+
+``.*[.][^b].*$`` The first attempt above tries to exclude ``bat`` by requiring
+that the first character of the extension is not a ``b``. This is wrong,
+because the pattern also doesn't match ``foo.bar``.
+
+.. % $
+
+``.*[.]([^b]..|.[^a].|..[^t])$``
+
+.. % Messes up the HTML without the curly braces around \^
+
+The expression gets messier when you try to patch up the first solution by
+requiring one of the following cases to match: the first character of the
+extension isn't ``b``; the second character isn't ``a``; or the third character
+isn't ``t``. This accepts ``foo.bar`` and rejects ``autoexec.bat``, but it
+requires a three-letter extension and won't accept a filename with a two-letter
+extension such as ``sendmail.cf``. We'll complicate the pattern again in an
+effort to fix it.
+
+``.*[.]([^b].?.?|.[^a]?.?|..?[^t]?)$``
+
+In the third attempt, the second and third letters are all made optional in
+order to allow matching extensions shorter than three characters, such as
+``sendmail.cf``.
+
+The pattern's getting really complicated now, which makes it hard to read and
+understand. Worse, if the problem changes and you want to exclude both ``bat``
+and ``exe`` as extensions, the pattern would get even more complicated and
+confusing.
+
+A negative lookahead cuts through all this confusion:
+
+``.*[.](?!bat$).*$`` The negative lookahead means: if the expression ``bat``
+doesn't match at this point, try the rest of the pattern; if ``bat$`` does
+match, the whole pattern will fail. The trailing ``$`` is required to ensure
+that something like ``sample.batch``, where the extension only starts with
+``bat``, will be allowed.
+
+.. % $
+
+Excluding another filename extension is now easy; simply add it as an
+alternative inside the assertion. The following pattern excludes filenames that
+end in either ``bat`` or ``exe``:
+
+``.*[.](?!bat$|exe$).*$``
+
+.. % $
+
+
+Modifying Strings
+=================
+
+Up to this point, we've simply performed searches against a static string.
+Regular expressions are also commonly used to modify strings in various ways,
+using the following :class:`RegexObject` methods:
+
++------------------+-----------------------------------------------+
+| Method/Attribute | Purpose |
++==================+===============================================+
+| ``split()`` | Split the string into a list, splitting it |
+| | wherever the RE matches |
++------------------+-----------------------------------------------+
+| ``sub()`` | Find all substrings where the RE matches, and |
+| | replace them with a different string |
++------------------+-----------------------------------------------+
+| ``subn()`` | Does the same thing as :meth:`sub`, but |
+| | returns the new string and the number of |
+| | replacements |
++------------------+-----------------------------------------------+
+
+
+Splitting Strings
+-----------------
+
+The :meth:`split` method of a :class:`RegexObject` splits a string apart
+wherever the RE matches, returning a list of the pieces. It's similar to the
+:meth:`split` method of strings but provides much more generality in the
+delimiters that you can split by; :meth:`split` only supports splitting by
+whitespace or by a fixed string. As you'd expect, there's a module-level
+:func:`re.split` function, too.
+
+
+.. method:: .split(string [, maxsplit=0])
+ :noindex:
+
+ Split *string* by the matches of the regular expression. If capturing
+ parentheses are used in the RE, then their contents will also be returned as
+ part of the resulting list. If *maxsplit* is nonzero, at most *maxsplit* splits
+ are performed.
+
+You can limit the number of splits made, by passing a value for *maxsplit*.
+When *maxsplit* is nonzero, at most *maxsplit* splits will be made, and the
+remainder of the string is returned as the final element of the list. In the
+following example, the delimiter is any sequence of non-alphanumeric characters.
+::
+
+ >>> p = re.compile(r'\W+')
+ >>> p.split('This is a test, short and sweet, of split().')
+ ['This', 'is', 'a', 'test', 'short', 'and', 'sweet', 'of', 'split', '']
+ >>> p.split('This is a test, short and sweet, of split().', 3)
+ ['This', 'is', 'a', 'test, short and sweet, of split().']
+
+Sometimes you're not only interested in what the text between delimiters is, but
+also need to know what the delimiter was. If capturing parentheses are used in
+the RE, then their values are also returned as part of the list. Compare the
+following calls::
+
+ >>> p = re.compile(r'\W+')
+ >>> p2 = re.compile(r'(\W+)')
+ >>> p.split('This... is a test.')
+ ['This', 'is', 'a', 'test', '']
+ >>> p2.split('This... is a test.')
+ ['This', '... ', 'is', ' ', 'a', ' ', 'test', '.', '']
+
+The module-level function :func:`re.split` adds the RE to be used as the first
+argument, but is otherwise the same. ::
+
+ >>> re.split('[\W]+', 'Words, words, words.')
+ ['Words', 'words', 'words', '']
+ >>> re.split('([\W]+)', 'Words, words, words.')
+ ['Words', ', ', 'words', ', ', 'words', '.', '']
+ >>> re.split('[\W]+', 'Words, words, words.', 1)
+ ['Words', 'words, words.']
+
+
+Search and Replace
+------------------
+
+Another common task is to find all the matches for a pattern, and replace them
+with a different string. The :meth:`sub` method takes a replacement value,
+which can be either a string or a function, and the string to be processed.
+
+
+.. method:: .sub(replacement, string[, count=0])
+ :noindex:
+
+ Returns the string obtained by replacing the leftmost non-overlapping
+ occurrences of the RE in *string* by the replacement *replacement*. If the
+ pattern isn't found, *string* is returned unchanged.
+
+ The optional argument *count* is the maximum number of pattern occurrences to be
+ replaced; *count* must be a non-negative integer. The default value of 0 means
+ to replace all occurrences.
+
+Here's a simple example of using the :meth:`sub` method. It replaces colour
+names with the word ``colour``::
+
+ >>> p = re.compile( '(blue|white|red)')
+ >>> p.sub( 'colour', 'blue socks and red shoes')
+ 'colour socks and colour shoes'
+ >>> p.sub( 'colour', 'blue socks and red shoes', count=1)
+ 'colour socks and red shoes'
+
+The :meth:`subn` method does the same work, but returns a 2-tuple containing the
+new string value and the number of replacements that were performed::
+
+ >>> p = re.compile( '(blue|white|red)')
+ >>> p.subn( 'colour', 'blue socks and red shoes')
+ ('colour socks and colour shoes', 2)
+ >>> p.subn( 'colour', 'no colours at all')
+ ('no colours at all', 0)
+
+Empty matches are replaced only when they're not adjacent to a previous match.
+::
+
+ >>> p = re.compile('x*')
+ >>> p.sub('-', 'abxd')
+ '-a-b-d-'
+
+If *replacement* is a string, any backslash escapes in it are processed. That
+is, ``\n`` is converted to a single newline character, ``\r`` is converted to a
+carriage return, and so forth. Unknown escapes such as ``\j`` are left alone.
+Backreferences, such as ``\6``, are replaced with the substring matched by the
+corresponding group in the RE. This lets you incorporate portions of the
+original text in the resulting replacement string.
+
+This example matches the word ``section`` followed by a string enclosed in
+``{``, ``}``, and changes ``section`` to ``subsection``::
+
+ >>> p = re.compile('section{ ( [^}]* ) }', re.VERBOSE)
+ >>> p.sub(r'subsection{\1}','section{First} section{second}')
+ 'subsection{First} subsection{second}'
+
+There's also a syntax for referring to named groups as defined by the
+``(?P<name>...)`` syntax. ``\g<name>`` will use the substring matched by the
+group named ``name``, and ``\g<number>`` uses the corresponding group number.
+``\g<2>`` is therefore equivalent to ``\2``, but isn't ambiguous in a
+replacement string such as ``\g<2>0``. (``\20`` would be interpreted as a
+reference to group 20, not a reference to group 2 followed by the literal
+character ``'0'``.) The following substitutions are all equivalent, but use all
+three variations of the replacement string. ::
+
+ >>> p = re.compile('section{ (?P<name> [^}]* ) }', re.VERBOSE)
+ >>> p.sub(r'subsection{\1}','section{First}')
+ 'subsection{First}'
+ >>> p.sub(r'subsection{\g<1>}','section{First}')
+ 'subsection{First}'
+ >>> p.sub(r'subsection{\g<name>}','section{First}')
+ 'subsection{First}'
+
+*replacement* can also be a function, which gives you even more control. If
+*replacement* is a function, the function is called for every non-overlapping
+occurrence of *pattern*. On each call, the function is passed a
+:class:`MatchObject` argument for the match and can use this information to
+compute the desired replacement string and return it.
+
+In the following example, the replacement function translates decimals into
+hexadecimal::
+
+ >>> def hexrepl( match ):
+ ... "Return the hex string for a decimal number"
+ ... value = int( match.group() )
+ ... return hex(value)
+ ...
+ >>> p = re.compile(r'\d+')
+ >>> p.sub(hexrepl, 'Call 65490 for printing, 49152 for user code.')
+ 'Call 0xffd2 for printing, 0xc000 for user code.'
+
+When using the module-level :func:`re.sub` function, the pattern is passed as
+the first argument. The pattern may be a string or a :class:`RegexObject`; if
+you need to specify regular expression flags, you must either use a
+:class:`RegexObject` as the first parameter, or use embedded modifiers in the
+pattern, e.g. ``sub("(?i)b+", "x", "bbbb BBBB")`` returns ``'x x'``.
+
+
+Common Problems
+===============
+
+Regular expressions are a powerful tool for some applications, but in some ways
+their behaviour isn't intuitive and at times they don't behave the way you may
+expect them to. This section will point out some of the most common pitfalls.
+
+
+Use String Methods
+------------------
+
+Sometimes using the :mod:`re` module is a mistake. If you're matching a fixed
+string, or a single character class, and you're not using any :mod:`re` features
+such as the :const:`IGNORECASE` flag, then the full power of regular expressions
+may not be required. Strings have several methods for performing operations with
+fixed strings and they're usually much faster, because the implementation is a
+single small C loop that's been optimized for the purpose, instead of the large,
+more generalized regular expression engine.
+
+One example might be replacing a single fixed string with another one; for
+example, you might replace ``word`` with ``deed``. ``re.sub()`` seems like the
+function to use for this, but consider the :meth:`replace` method. Note that
+:func:`replace` will also replace ``word`` inside words, turning ``swordfish``
+into ``sdeedfish``, but the naive RE ``word`` would have done that, too. (To
+avoid performing the substitution on parts of words, the pattern would have to
+be ``\bword\b``, in order to require that ``word`` have a word boundary on
+either side. This takes the job beyond :meth:`replace`'s abilities.)
+
+Another common task is deleting every occurrence of a single character from a
+string or replacing it with another single character. You might do this with
+something like ``re.sub('\n', ' ', S)``, but :meth:`translate` is capable of
+doing both tasks and will be faster than any regular expression operation can
+be.
+
+In short, before turning to the :mod:`re` module, consider whether your problem
+can be solved with a faster and simpler string method.
+
+
+match() versus search()
+-----------------------
+
+The :func:`match` function only checks if the RE matches at the beginning of the
+string while :func:`search` will scan forward through the string for a match.
+It's important to keep this distinction in mind. Remember, :func:`match` will
+only report a successful match which will start at 0; if the match wouldn't
+start at zero, :func:`match` will *not* report it. ::
+
+ >>> print re.match('super', 'superstition').span()
+ (0, 5)
+ >>> print re.match('super', 'insuperable')
+ None
+
+On the other hand, :func:`search` will scan forward through the string,
+reporting the first match it finds. ::
+
+ >>> print re.search('super', 'superstition').span()
+ (0, 5)
+ >>> print re.search('super', 'insuperable').span()
+ (2, 7)
+
+Sometimes you'll be tempted to keep using :func:`re.match`, and just add ``.*``
+to the front of your RE. Resist this temptation and use :func:`re.search`
+instead. The regular expression compiler does some analysis of REs in order to
+speed up the process of looking for a match. One such analysis figures out what
+the first character of a match must be; for example, a pattern starting with
+``Crow`` must match starting with a ``'C'``. The analysis lets the engine
+quickly scan through the string looking for the starting character, only trying
+the full match if a ``'C'`` is found.
+
+Adding ``.*`` defeats this optimization, requiring scanning to the end of the
+string and then backtracking to find a match for the rest of the RE. Use
+:func:`re.search` instead.
+
+
+Greedy versus Non-Greedy
+------------------------
+
+When repeating a regular expression, as in ``a*``, the resulting action is to
+consume as much of the pattern as possible. This fact often bites you when
+you're trying to match a pair of balanced delimiters, such as the angle brackets
+surrounding an HTML tag. The naive pattern for matching a single HTML tag
+doesn't work because of the greedy nature of ``.*``. ::
+
+ >>> s = '<html><head><title>Title</title>'
+ >>> len(s)
+ 32
+ >>> print re.match('<.*>', s).span()
+ (0, 32)
+ >>> print re.match('<.*>', s).group()
+ <html><head><title>Title</title>
+
+The RE matches the ``'<'`` in ``<html>``, and the ``.*`` consumes the rest of
+the string. There's still more left in the RE, though, and the ``>`` can't
+match at the end of the string, so the regular expression engine has to
+backtrack character by character until it finds a match for the ``>``. The
+final match extends from the ``'<'`` in ``<html>`` to the ``'>'`` in
+``</title>``, which isn't what you want.
+
+In this case, the solution is to use the non-greedy qualifiers ``*?``, ``+?``,
+``??``, or ``{m,n}?``, which match as *little* text as possible. In the above
+example, the ``'>'`` is tried immediately after the first ``'<'`` matches, and
+when it fails, the engine advances a character at a time, retrying the ``'>'``
+at every step. This produces just the right result::
+
+ >>> print re.match('<.*?>', s).group()
+ <html>
+
+(Note that parsing HTML or XML with regular expressions is painful.
+Quick-and-dirty patterns will handle common cases, but HTML and XML have special
+cases that will break the obvious regular expression; by the time you've written
+a regular expression that handles all of the possible cases, the patterns will
+be *very* complicated. Use an HTML or XML parser module for such tasks.)
+
+
+Not Using re.VERBOSE
+--------------------
+
+By now you've probably noticed that regular expressions are a very compact
+notation, but they're not terribly readable. REs of moderate complexity can
+become lengthy collections of backslashes, parentheses, and metacharacters,
+making them difficult to read and understand.
+
+For such REs, specifying the ``re.VERBOSE`` flag when compiling the regular
+expression can be helpful, because it allows you to format the regular
+expression more clearly.
+
+The ``re.VERBOSE`` flag has several effects. Whitespace in the regular
+expression that *isn't* inside a character class is ignored. This means that an
+expression such as ``dog | cat`` is equivalent to the less readable ``dog|cat``,
+but ``[a b]`` will still match the characters ``'a'``, ``'b'``, or a space. In
+addition, you can also put comments inside a RE; comments extend from a ``#``
+character to the next newline. When used with triple-quoted strings, this
+enables REs to be formatted more neatly::
+
+ pat = re.compile(r"""
+ \s* # Skip leading whitespace
+ (?P<header>[^:]+) # Header name
+ \s* : # Whitespace, and a colon
+ (?P<value>.*?) # The header's value -- *? used to
+ # lose the following trailing whitespace
+ \s*$ # Trailing whitespace to end-of-line
+ """, re.VERBOSE)
+
+This is far more readable than:
+
+.. % $
+
+::
+
+ pat = re.compile(r"\s*(?P<header>[^:]+)\s*:(?P<value>.*?)\s*$")
+
+.. % $
+
+
+Feedback
+========
+
+Regular expressions are a complicated topic. Did this document help you
+understand them? Were there parts that were unclear, or Problems you
+encountered that weren't covered here? If so, please send suggestions for
+improvements to the author.
+
+The most complete book on regular expressions is almost certainly Jeffrey
+Friedl's Mastering Regular Expressions, published by O'Reilly. Unfortunately,
+it exclusively concentrates on Perl and Java's flavours of regular expressions,
+and doesn't contain any Python material at all, so it won't be useful as a
+reference for programming in Python. (The first edition covered Python's
+now-removed :mod:`regex` module, which won't help you much.) Consider checking
+it out from your library.
+
+
+.. rubric:: Footnotes
+
+.. [#] Introduced in Python 2.2.2.
+
diff --git a/Doc/howto/sockets.rst b/Doc/howto/sockets.rst
new file mode 100644
index 0000000000..dc05d3269a
--- /dev/null
+++ b/Doc/howto/sockets.rst
@@ -0,0 +1,421 @@
+****************************
+ Socket Programming HOWTO
+****************************
+
+:Author: Gordon McMillan
+
+
+.. topic:: Abstract
+
+ Sockets are used nearly everywhere, but are one of the most severely
+ misunderstood technologies around. This is a 10,000 foot overview of sockets.
+ It's not really a tutorial - you'll still have work to do in getting things
+ operational. It doesn't cover the fine points (and there are a lot of them), but
+ I hope it will give you enough background to begin using them decently.
+
+
+Sockets
+=======
+
+Sockets are used nearly everywhere, but are one of the most severely
+misunderstood technologies around. This is a 10,000 foot overview of sockets.
+It's not really a tutorial - you'll still have work to do in getting things
+working. It doesn't cover the fine points (and there are a lot of them), but I
+hope it will give you enough background to begin using them decently.
+
+I'm only going to talk about INET sockets, but they account for at least 99% of
+the sockets in use. And I'll only talk about STREAM sockets - unless you really
+know what you're doing (in which case this HOWTO isn't for you!), you'll get
+better behavior and performance from a STREAM socket than anything else. I will
+try to clear up the mystery of what a socket is, as well as some hints on how to
+work with blocking and non-blocking sockets. But I'll start by talking about
+blocking sockets. You'll need to know how they work before dealing with
+non-blocking sockets.
+
+Part of the trouble with understanding these things is that "socket" can mean a
+number of subtly different things, depending on context. So first, let's make a
+distinction between a "client" socket - an endpoint of a conversation, and a
+"server" socket, which is more like a switchboard operator. The client
+application (your browser, for example) uses "client" sockets exclusively; the
+web server it's talking to uses both "server" sockets and "client" sockets.
+
+
+History
+-------
+
+Of the various forms of IPC (*Inter Process Communication*), sockets are by far
+the most popular. On any given platform, there are likely to be other forms of
+IPC that are faster, but for cross-platform communication, sockets are about the
+only game in town.
+
+They were invented in Berkeley as part of the BSD flavor of Unix. They spread
+like wildfire with the Internet. With good reason --- the combination of sockets
+with INET makes talking to arbitrary machines around the world unbelievably easy
+(at least compared to other schemes).
+
+
+Creating a Socket
+=================
+
+Roughly speaking, when you clicked on the link that brought you to this page,
+your browser did something like the following::
+
+ #create an INET, STREAMing socket
+ s = socket.socket(
+ socket.AF_INET, socket.SOCK_STREAM)
+ #now connect to the web server on port 80
+ # - the normal http port
+ s.connect(("www.mcmillan-inc.com", 80))
+
+When the ``connect`` completes, the socket ``s`` can now be used to send in a
+request for the text of this page. The same socket will read the reply, and then
+be destroyed. That's right - destroyed. Client sockets are normally only used
+for one exchange (or a small set of sequential exchanges).
+
+What happens in the web server is a bit more complex. First, the web server
+creates a "server socket". ::
+
+ #create an INET, STREAMing socket
+ serversocket = socket.socket(
+ socket.AF_INET, socket.SOCK_STREAM)
+ #bind the socket to a public host,
+ # and a well-known port
+ serversocket.bind((socket.gethostname(), 80))
+ #become a server socket
+ serversocket.listen(5)
+
+A couple things to notice: we used ``socket.gethostname()`` so that the socket
+would be visible to the outside world. If we had used ``s.bind(('', 80))`` or
+``s.bind(('localhost', 80))`` or ``s.bind(('127.0.0.1', 80))`` we would still
+have a "server" socket, but one that was only visible within the same machine.
+
+A second thing to note: low number ports are usually reserved for "well known"
+services (HTTP, SNMP etc). If you're playing around, use a nice high number (4
+digits).
+
+Finally, the argument to ``listen`` tells the socket library that we want it to
+queue up as many as 5 connect requests (the normal max) before refusing outside
+connections. If the rest of the code is written properly, that should be plenty.
+
+OK, now we have a "server" socket, listening on port 80. Now we enter the
+mainloop of the web server::
+
+ while 1:
+ #accept connections from outside
+ (clientsocket, address) = serversocket.accept()
+ #now do something with the clientsocket
+ #in this case, we'll pretend this is a threaded server
+ ct = client_thread(clientsocket)
+ ct.run()
+
+There's actually 3 general ways in which this loop could work - dispatching a
+thread to handle ``clientsocket``, create a new process to handle
+``clientsocket``, or restructure this app to use non-blocking sockets, and
+mulitplex between our "server" socket and any active ``clientsocket``\ s using
+``select``. More about that later. The important thing to understand now is
+this: this is *all* a "server" socket does. It doesn't send any data. It doesn't
+receive any data. It just produces "client" sockets. Each ``clientsocket`` is
+created in response to some *other* "client" socket doing a ``connect()`` to the
+host and port we're bound to. As soon as we've created that ``clientsocket``, we
+go back to listening for more connections. The two "clients" are free to chat it
+up - they are using some dynamically allocated port which will be recycled when
+the conversation ends.
+
+
+IPC
+---
+
+If you need fast IPC between two processes on one machine, you should look into
+whatever form of shared memory the platform offers. A simple protocol based
+around shared memory and locks or semaphores is by far the fastest technique.
+
+If you do decide to use sockets, bind the "server" socket to ``'localhost'``. On
+most platforms, this will take a shortcut around a couple of layers of network
+code and be quite a bit faster.
+
+
+Using a Socket
+==============
+
+The first thing to note, is that the web browser's "client" socket and the web
+server's "client" socket are identical beasts. That is, this is a "peer to peer"
+conversation. Or to put it another way, *as the designer, you will have to
+decide what the rules of etiquette are for a conversation*. Normally, the
+``connect``\ ing socket starts the conversation, by sending in a request, or
+perhaps a signon. But that's a design decision - it's not a rule of sockets.
+
+Now there are two sets of verbs to use for communication. You can use ``send``
+and ``recv``, or you can transform your client socket into a file-like beast and
+use ``read`` and ``write``. The latter is the way Java presents their sockets.
+I'm not going to talk about it here, except to warn you that you need to use
+``flush`` on sockets. These are buffered "files", and a common mistake is to
+``write`` something, and then ``read`` for a reply. Without a ``flush`` in
+there, you may wait forever for the reply, because the request may still be in
+your output buffer.
+
+Now we come the major stumbling block of sockets - ``send`` and ``recv`` operate
+on the network buffers. They do not necessarily handle all the bytes you hand
+them (or expect from them), because their major focus is handling the network
+buffers. In general, they return when the associated network buffers have been
+filled (``send``) or emptied (``recv``). They then tell you how many bytes they
+handled. It is *your* responsibility to call them again until your message has
+been completely dealt with.
+
+When a ``recv`` returns 0 bytes, it means the other side has closed (or is in
+the process of closing) the connection. You will not receive any more data on
+this connection. Ever. You may be able to send data successfully; I'll talk
+about that some on the next page.
+
+A protocol like HTTP uses a socket for only one transfer. The client sends a
+request, the reads a reply. That's it. The socket is discarded. This means that
+a client can detect the end of the reply by receiving 0 bytes.
+
+But if you plan to reuse your socket for further transfers, you need to realize
+that *there is no "EOT" (End of Transfer) on a socket.* I repeat: if a socket
+``send`` or ``recv`` returns after handling 0 bytes, the connection has been
+broken. If the connection has *not* been broken, you may wait on a ``recv``
+forever, because the socket will *not* tell you that there's nothing more to
+read (for now). Now if you think about that a bit, you'll come to realize a
+fundamental truth of sockets: *messages must either be fixed length* (yuck), *or
+be delimited* (shrug), *or indicate how long they are* (much better), *or end by
+shutting down the connection*. The choice is entirely yours, (but some ways are
+righter than others).
+
+Assuming you don't want to end the connection, the simplest solution is a fixed
+length message::
+
+ class mysocket:
+ '''demonstration class only
+ - coded for clarity, not efficiency
+ '''
+
+ def __init__(self, sock=None):
+ if sock is None:
+ self.sock = socket.socket(
+ socket.AF_INET, socket.SOCK_STREAM)
+ else:
+ self.sock = sock
+
+ def connect(self, host, port):
+ self.sock.connect((host, port))
+
+ def mysend(self, msg):
+ totalsent = 0
+ while totalsent < MSGLEN:
+ sent = self.sock.send(msg[totalsent:])
+ if sent == 0:
+ raise RuntimeError, \
+ "socket connection broken"
+ totalsent = totalsent + sent
+
+ def myreceive(self):
+ msg = ''
+ while len(msg) < MSGLEN:
+ chunk = self.sock.recv(MSGLEN-len(msg))
+ if chunk == '':
+ raise RuntimeError, \
+ "socket connection broken"
+ msg = msg + chunk
+ return msg
+
+The sending code here is usable for almost any messaging scheme - in Python you
+send strings, and you can use ``len()`` to determine its length (even if it has
+embedded ``\0`` characters). It's mostly the receiving code that gets more
+complex. (And in C, it's not much worse, except you can't use ``strlen`` if the
+message has embedded ``\0``\ s.)
+
+The easiest enhancement is to make the first character of the message an
+indicator of message type, and have the type determine the length. Now you have
+two ``recv``\ s - the first to get (at least) that first character so you can
+look up the length, and the second in a loop to get the rest. If you decide to
+go the delimited route, you'll be receiving in some arbitrary chunk size, (4096
+or 8192 is frequently a good match for network buffer sizes), and scanning what
+you've received for a delimiter.
+
+One complication to be aware of: if your conversational protocol allows multiple
+messages to be sent back to back (without some kind of reply), and you pass
+``recv`` an arbitrary chunk size, you may end up reading the start of a
+following message. You'll need to put that aside and hold onto it, until it's
+needed.
+
+Prefixing the message with it's length (say, as 5 numeric characters) gets more
+complex, because (believe it or not), you may not get all 5 characters in one
+``recv``. In playing around, you'll get away with it; but in high network loads,
+your code will very quickly break unless you use two ``recv`` loops - the first
+to determine the length, the second to get the data part of the message. Nasty.
+This is also when you'll discover that ``send`` does not always manage to get
+rid of everything in one pass. And despite having read this, you will eventually
+get bit by it!
+
+In the interests of space, building your character, (and preserving my
+competitive position), these enhancements are left as an exercise for the
+reader. Lets move on to cleaning up.
+
+
+Binary Data
+-----------
+
+It is perfectly possible to send binary data over a socket. The major problem is
+that not all machines use the same formats for binary data. For example, a
+Motorola chip will represent a 16 bit integer with the value 1 as the two hex
+bytes 00 01. Intel and DEC, however, are byte-reversed - that same 1 is 01 00.
+Socket libraries have calls for converting 16 and 32 bit integers - ``ntohl,
+htonl, ntohs, htons`` where "n" means *network* and "h" means *host*, "s" means
+*short* and "l" means *long*. Where network order is host order, these do
+nothing, but where the machine is byte-reversed, these swap the bytes around
+appropriately.
+
+In these days of 32 bit machines, the ascii representation of binary data is
+frequently smaller than the binary representation. That's because a surprising
+amount of the time, all those longs have the value 0, or maybe 1. The string "0"
+would be two bytes, while binary is four. Of course, this doesn't fit well with
+fixed-length messages. Decisions, decisions.
+
+
+Disconnecting
+=============
+
+Strictly speaking, you're supposed to use ``shutdown`` on a socket before you
+``close`` it. The ``shutdown`` is an advisory to the socket at the other end.
+Depending on the argument you pass it, it can mean "I'm not going to send
+anymore, but I'll still listen", or "I'm not listening, good riddance!". Most
+socket libraries, however, are so used to programmers neglecting to use this
+piece of etiquette that normally a ``close`` is the same as ``shutdown();
+close()``. So in most situations, an explicit ``shutdown`` is not needed.
+
+One way to use ``shutdown`` effectively is in an HTTP-like exchange. The client
+sends a request and then does a ``shutdown(1)``. This tells the server "This
+client is done sending, but can still receive." The server can detect "EOF" by
+a receive of 0 bytes. It can assume it has the complete request. The server
+sends a reply. If the ``send`` completes successfully then, indeed, the client
+was still receiving.
+
+Python takes the automatic shutdown a step further, and says that when a socket
+is garbage collected, it will automatically do a ``close`` if it's needed. But
+relying on this is a very bad habit. If your socket just disappears without
+doing a ``close``, the socket at the other end may hang indefinitely, thinking
+you're just being slow. *Please* ``close`` your sockets when you're done.
+
+
+When Sockets Die
+----------------
+
+Probably the worst thing about using blocking sockets is what happens when the
+other side comes down hard (without doing a ``close``). Your socket is likely to
+hang. SOCKSTREAM is a reliable protocol, and it will wait a long, long time
+before giving up on a connection. If you're using threads, the entire thread is
+essentially dead. There's not much you can do about it. As long as you aren't
+doing something dumb, like holding a lock while doing a blocking read, the
+thread isn't really consuming much in the way of resources. Do *not* try to kill
+the thread - part of the reason that threads are more efficient than processes
+is that they avoid the overhead associated with the automatic recycling of
+resources. In other words, if you do manage to kill the thread, your whole
+process is likely to be screwed up.
+
+
+Non-blocking Sockets
+====================
+
+If you've understood the preceeding, you already know most of what you need to
+know about the mechanics of using sockets. You'll still use the same calls, in
+much the same ways. It's just that, if you do it right, your app will be almost
+inside-out.
+
+In Python, you use ``socket.setblocking(0)`` to make it non-blocking. In C, it's
+more complex, (for one thing, you'll need to choose between the BSD flavor
+``O_NONBLOCK`` and the almost indistinguishable Posix flavor ``O_NDELAY``, which
+is completely different from ``TCP_NODELAY``), but it's the exact same idea. You
+do this after creating the socket, but before using it. (Actually, if you're
+nuts, you can switch back and forth.)
+
+The major mechanical difference is that ``send``, ``recv``, ``connect`` and
+``accept`` can return without having done anything. You have (of course) a
+number of choices. You can check return code and error codes and generally drive
+yourself crazy. If you don't believe me, try it sometime. Your app will grow
+large, buggy and suck CPU. So let's skip the brain-dead solutions and do it
+right.
+
+Use ``select``.
+
+In C, coding ``select`` is fairly complex. In Python, it's a piece of cake, but
+it's close enough to the C version that if you understand ``select`` in Python,
+you'll have little trouble with it in C. ::
+
+ ready_to_read, ready_to_write, in_error = \
+ select.select(
+ potential_readers,
+ potential_writers,
+ potential_errs,
+ timeout)
+
+You pass ``select`` three lists: the first contains all sockets that you might
+want to try reading; the second all the sockets you might want to try writing
+to, and the last (normally left empty) those that you want to check for errors.
+You should note that a socket can go into more than one list. The ``select``
+call is blocking, but you can give it a timeout. This is generally a sensible
+thing to do - give it a nice long timeout (say a minute) unless you have good
+reason to do otherwise.
+
+In return, you will get three lists. They have the sockets that are actually
+readable, writable and in error. Each of these lists is a subset (possbily
+empty) of the corresponding list you passed in. And if you put a socket in more
+than one input list, it will only be (at most) in one output list.
+
+If a socket is in the output readable list, you can be
+as-close-to-certain-as-we-ever-get-in-this-business that a ``recv`` on that
+socket will return *something*. Same idea for the writable list. You'll be able
+to send *something*. Maybe not all you want to, but *something* is better than
+nothing. (Actually, any reasonably healthy socket will return as writable - it
+just means outbound network buffer space is available.)
+
+If you have a "server" socket, put it in the potential_readers list. If it comes
+out in the readable list, your ``accept`` will (almost certainly) work. If you
+have created a new socket to ``connect`` to someone else, put it in the
+ptoential_writers list. If it shows up in the writable list, you have a decent
+chance that it has connected.
+
+One very nasty problem with ``select``: if somewhere in those input lists of
+sockets is one which has died a nasty death, the ``select`` will fail. You then
+need to loop through every single damn socket in all those lists and do a
+``select([sock],[],[],0)`` until you find the bad one. That timeout of 0 means
+it won't take long, but it's ugly.
+
+Actually, ``select`` can be handy even with blocking sockets. It's one way of
+determining whether you will block - the socket returns as readable when there's
+something in the buffers. However, this still doesn't help with the problem of
+determining whether the other end is done, or just busy with something else.
+
+**Portability alert**: On Unix, ``select`` works both with the sockets and
+files. Don't try this on Windows. On Windows, ``select`` works with sockets
+only. Also note that in C, many of the more advanced socket options are done
+differently on Windows. In fact, on Windows I usually use threads (which work
+very, very well) with my sockets. Face it, if you want any kind of performance,
+your code will look very different on Windows than on Unix. (I haven't the
+foggiest how you do this stuff on a Mac.)
+
+
+Performance
+-----------
+
+There's no question that the fastest sockets code uses non-blocking sockets and
+select to multiplex them. You can put together something that will saturate a
+LAN connection without putting any strain on the CPU. The trouble is that an app
+written this way can't do much of anything else - it needs to be ready to
+shuffle bytes around at all times.
+
+Assuming that your app is actually supposed to do something more than that,
+threading is the optimal solution, (and using non-blocking sockets will be
+faster than using blocking sockets). Unfortunately, threading support in Unixes
+varies both in API and quality. So the normal Unix solution is to fork a
+subprocess to deal with each connection. The overhead for this is significant
+(and don't do this on Windows - the overhead of process creation is enormous
+there). It also means that unless each subprocess is completely independent,
+you'll need to use another form of IPC, say a pipe, or shared memory and
+semaphores, to communicate between the parent and child processes.
+
+Finally, remember that even though blocking sockets are somewhat slower than
+non-blocking, in many cases they are the "right" solution. After all, if your
+app is driven by the data it receives over a socket, there's not much sense in
+complicating the logic just so your app can wait on ``select`` instead of
+``recv``.
+
diff --git a/Doc/howto/unicode.rst b/Doc/howto/unicode.rst
new file mode 100644
index 0000000000..16bd5a8a2f
--- /dev/null
+++ b/Doc/howto/unicode.rst
@@ -0,0 +1,732 @@
+*****************
+ Unicode HOWTO
+*****************
+
+:Release: 1.02
+
+This HOWTO discusses Python's support for Unicode, and explains various problems
+that people commonly encounter when trying to work with Unicode.
+
+Introduction to Unicode
+=======================
+
+History of Character Codes
+--------------------------
+
+In 1968, the American Standard Code for Information Interchange, better known by
+its acronym ASCII, was standardized. ASCII defined numeric codes for various
+characters, with the numeric values running from 0 to
+127. For example, the lowercase letter 'a' is assigned 97 as its code
+value.
+
+ASCII was an American-developed standard, so it only defined unaccented
+characters. There was an 'e', but no 'é' or 'Í'. This meant that languages
+which required accented characters couldn't be faithfully represented in ASCII.
+(Actually the missing accents matter for English, too, which contains words such
+as 'naïve' and 'café', and some publications have house styles which require
+spellings such as 'coöperate'.)
+
+For a while people just wrote programs that didn't display accents. I remember
+looking at Apple ][ BASIC programs, published in French-language publications in
+the mid-1980s, that had lines like these::
+
+ PRINT "FICHER EST COMPLETE."
+ PRINT "CARACTERE NON ACCEPTE."
+
+Those messages should contain accents, and they just look wrong to someone who
+can read French.
+
+In the 1980s, almost all personal computers were 8-bit, meaning that bytes could
+hold values ranging from 0 to 255. ASCII codes only went up to 127, so some
+machines assigned values between 128 and 255 to accented characters. Different
+machines had different codes, however, which led to problems exchanging files.
+Eventually various commonly used sets of values for the 128-255 range emerged.
+Some were true standards, defined by the International Standards Organization,
+and some were **de facto** conventions that were invented by one company or
+another and managed to catch on.
+
+255 characters aren't very many. For example, you can't fit both the accented
+characters used in Western Europe and the Cyrillic alphabet used for Russian
+into the 128-255 range because there are more than 127 such characters.
+
+You could write files using different codes (all your Russian files in a coding
+system called KOI8, all your French files in a different coding system called
+Latin1), but what if you wanted to write a French document that quotes some
+Russian text? In the 1980s people began to want to solve this problem, and the
+Unicode standardization effort began.
+
+Unicode started out using 16-bit characters instead of 8-bit characters. 16
+bits means you have 2^16 = 65,536 distinct values available, making it possible
+to represent many different characters from many different alphabets; an initial
+goal was to have Unicode contain the alphabets for every single human language.
+It turns out that even 16 bits isn't enough to meet that goal, and the modern
+Unicode specification uses a wider range of codes, 0-1,114,111 (0x10ffff in
+base-16).
+
+There's a related ISO standard, ISO 10646. Unicode and ISO 10646 were
+originally separate efforts, but the specifications were merged with the 1.1
+revision of Unicode.
+
+(This discussion of Unicode's history is highly simplified. I don't think the
+average Python programmer needs to worry about the historical details; consult
+the Unicode consortium site listed in the References for more information.)
+
+
+Definitions
+-----------
+
+A **character** is the smallest possible component of a text. 'A', 'B', 'C',
+etc., are all different characters. So are 'È' and 'Í'. Characters are
+abstractions, and vary depending on the language or context you're talking
+about. For example, the symbol for ohms (Ω) is usually drawn much like the
+capital letter omega (Ω) in the Greek alphabet (they may even be the same in
+some fonts), but these are two different characters that have different
+meanings.
+
+The Unicode standard describes how characters are represented by **code
+points**. A code point is an integer value, usually denoted in base 16. In the
+standard, a code point is written using the notation U+12ca to mean the
+character with value 0x12ca (4810 decimal). The Unicode standard contains a lot
+of tables listing characters and their corresponding code points::
+
+ 0061 'a'; LATIN SMALL LETTER A
+ 0062 'b'; LATIN SMALL LETTER B
+ 0063 'c'; LATIN SMALL LETTER C
+ ...
+ 007B '{'; LEFT CURLY BRACKET
+
+Strictly, these definitions imply that it's meaningless to say 'this is
+character U+12ca'. U+12ca is a code point, which represents some particular
+character; in this case, it represents the character 'ETHIOPIC SYLLABLE WI'. In
+informal contexts, this distinction between code points and characters will
+sometimes be forgotten.
+
+A character is represented on a screen or on paper by a set of graphical
+elements that's called a **glyph**. The glyph for an uppercase A, for example,
+is two diagonal strokes and a horizontal stroke, though the exact details will
+depend on the font being used. Most Python code doesn't need to worry about
+glyphs; figuring out the correct glyph to display is generally the job of a GUI
+toolkit or a terminal's font renderer.
+
+
+Encodings
+---------
+
+To summarize the previous section: a Unicode string is a sequence of code
+points, which are numbers from 0 to 0x10ffff. This sequence needs to be
+represented as a set of bytes (meaning, values from 0-255) in memory. The rules
+for translating a Unicode string into a sequence of bytes are called an
+**encoding**.
+
+The first encoding you might think of is an array of 32-bit integers. In this
+representation, the string "Python" would look like this::
+
+ P y t h o n
+ 0x50 00 00 00 79 00 00 00 74 00 00 00 68 00 00 00 6f 00 00 00 6e 00 00 00
+ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
+
+This representation is straightforward but using it presents a number of
+problems.
+
+1. It's not portable; different processors order the bytes differently.
+
+2. It's very wasteful of space. In most texts, the majority of the code points
+ are less than 127, or less than 255, so a lot of space is occupied by zero
+ bytes. The above string takes 24 bytes compared to the 6 bytes needed for an
+ ASCII representation. Increased RAM usage doesn't matter too much (desktop
+ computers have megabytes of RAM, and strings aren't usually that large), but
+ expanding our usage of disk and network bandwidth by a factor of 4 is
+ intolerable.
+
+3. It's not compatible with existing C functions such as ``strlen()``, so a new
+ family of wide string functions would need to be used.
+
+4. Many Internet standards are defined in terms of textual data, and can't
+ handle content with embedded zero bytes.
+
+Generally people don't use this encoding, instead choosing other encodings that
+are more efficient and convenient.
+
+Encodings don't have to handle every possible Unicode character, and most
+encodings don't. For example, Python's default encoding is the 'ascii'
+encoding. The rules for converting a Unicode string into the ASCII encoding are
+simple; for each code point:
+
+1. If the code point is < 128, each byte is the same as the value of the code
+ point.
+
+2. If the code point is 128 or greater, the Unicode string can't be represented
+ in this encoding. (Python raises a :exc:`UnicodeEncodeError` exception in this
+ case.)
+
+Latin-1, also known as ISO-8859-1, is a similar encoding. Unicode code points
+0-255 are identical to the Latin-1 values, so converting to this encoding simply
+requires converting code points to byte values; if a code point larger than 255
+is encountered, the string can't be encoded into Latin-1.
+
+Encodings don't have to be simple one-to-one mappings like Latin-1. Consider
+IBM's EBCDIC, which was used on IBM mainframes. Letter values weren't in one
+block: 'a' through 'i' had values from 129 to 137, but 'j' through 'r' were 145
+through 153. If you wanted to use EBCDIC as an encoding, you'd probably use
+some sort of lookup table to perform the conversion, but this is largely an
+internal detail.
+
+UTF-8 is one of the most commonly used encodings. UTF stands for "Unicode
+Transformation Format", and the '8' means that 8-bit numbers are used in the
+encoding. (There's also a UTF-16 encoding, but it's less frequently used than
+UTF-8.) UTF-8 uses the following rules:
+
+1. If the code point is <128, it's represented by the corresponding byte value.
+2. If the code point is between 128 and 0x7ff, it's turned into two byte values
+ between 128 and 255.
+3. Code points >0x7ff are turned into three- or four-byte sequences, where each
+ byte of the sequence is between 128 and 255.
+
+UTF-8 has several convenient properties:
+
+1. It can handle any Unicode code point.
+2. A Unicode string is turned into a string of bytes containing no embedded zero
+ bytes. This avoids byte-ordering issues, and means UTF-8 strings can be
+ processed by C functions such as ``strcpy()`` and sent through protocols that
+ can't handle zero bytes.
+3. A string of ASCII text is also valid UTF-8 text.
+4. UTF-8 is fairly compact; the majority of code points are turned into two
+ bytes, and values less than 128 occupy only a single byte.
+5. If bytes are corrupted or lost, it's possible to determine the start of the
+ next UTF-8-encoded code point and resynchronize. It's also unlikely that
+ random 8-bit data will look like valid UTF-8.
+
+
+
+References
+----------
+
+The Unicode Consortium site at <http://www.unicode.org> has character charts, a
+glossary, and PDF versions of the Unicode specification. Be prepared for some
+difficult reading. <http://www.unicode.org/history/> is a chronology of the
+origin and development of Unicode.
+
+To help understand the standard, Jukka Korpela has written an introductory guide
+to reading the Unicode character tables, available at
+<http://www.cs.tut.fi/~jkorpela/unicode/guide.html>.
+
+Roman Czyborra wrote another explanation of Unicode's basic principles; it's at
+<http://czyborra.com/unicode/characters.html>. Czyborra has written a number of
+other Unicode-related documentation, available from <http://www.cyzborra.com>.
+
+Two other good introductory articles were written by Joel Spolsky
+<http://www.joelonsoftware.com/articles/Unicode.html> and Jason Orendorff
+<http://www.jorendorff.com/articles/unicode/>. If this introduction didn't make
+things clear to you, you should try reading one of these alternate articles
+before continuing.
+
+Wikipedia entries are often helpful; see the entries for "character encoding"
+<http://en.wikipedia.org/wiki/Character_encoding> and UTF-8
+<http://en.wikipedia.org/wiki/UTF-8>, for example.
+
+
+Python's Unicode Support
+========================
+
+Now that you've learned the rudiments of Unicode, we can look at Python's
+Unicode features.
+
+
+The Unicode Type
+----------------
+
+Unicode strings are expressed as instances of the :class:`unicode` type, one of
+Python's repertoire of built-in types. It derives from an abstract type called
+:class:`basestring`, which is also an ancestor of the :class:`str` type; you can
+therefore check if a value is a string type with ``isinstance(value,
+basestring)``. Under the hood, Python represents Unicode strings as either 16-
+or 32-bit integers, depending on how the Python interpreter was compiled.
+
+The :func:`unicode` constructor has the signature ``unicode(string[, encoding,
+errors])``. All of its arguments should be 8-bit strings. The first argument
+is converted to Unicode using the specified encoding; if you leave off the
+``encoding`` argument, the ASCII encoding is used for the conversion, so
+characters greater than 127 will be treated as errors::
+
+ >>> unicode('abcdef')
+ u'abcdef'
+ >>> s = unicode('abcdef')
+ >>> type(s)
+ <type 'unicode'>
+ >>> unicode('abcdef' + chr(255))
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ UnicodeDecodeError: 'ascii' codec can't decode byte 0xff in position 6:
+ ordinal not in range(128)
+
+The ``errors`` argument specifies the response when the input string can't be
+converted according to the encoding's rules. Legal values for this argument are
+'strict' (raise a ``UnicodeDecodeError`` exception), 'replace' (add U+FFFD,
+'REPLACEMENT CHARACTER'), or 'ignore' (just leave the character out of the
+Unicode result). The following examples show the differences::
+
+ >>> unicode('\x80abc', errors='strict')
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ UnicodeDecodeError: 'ascii' codec can't decode byte 0x80 in position 0:
+ ordinal not in range(128)
+ >>> unicode('\x80abc', errors='replace')
+ u'\ufffdabc'
+ >>> unicode('\x80abc', errors='ignore')
+ u'abc'
+
+Encodings are specified as strings containing the encoding's name. Python 2.4
+comes with roughly 100 different encodings; see the Python Library Reference at
+<http://docs.python.org/lib/standard-encodings.html> for a list. Some encodings
+have multiple names; for example, 'latin-1', 'iso_8859_1' and '8859' are all
+synonyms for the same encoding.
+
+One-character Unicode strings can also be created with the :func:`unichr`
+built-in function, which takes integers and returns a Unicode string of length 1
+that contains the corresponding code point. The reverse operation is the
+built-in :func:`ord` function that takes a one-character Unicode string and
+returns the code point value::
+
+ >>> unichr(40960)
+ u'\ua000'
+ >>> ord(u'\ua000')
+ 40960
+
+Instances of the :class:`unicode` type have many of the same methods as the
+8-bit string type for operations such as searching and formatting::
+
+ >>> s = u'Was ever feather so lightly blown to and fro as this multitude?'
+ >>> s.count('e')
+ 5
+ >>> s.find('feather')
+ 9
+ >>> s.find('bird')
+ -1
+ >>> s.replace('feather', 'sand')
+ u'Was ever sand so lightly blown to and fro as this multitude?'
+ >>> s.upper()
+ u'WAS EVER FEATHER SO LIGHTLY BLOWN TO AND FRO AS THIS MULTITUDE?'
+
+Note that the arguments to these methods can be Unicode strings or 8-bit
+strings. 8-bit strings will be converted to Unicode before carrying out the
+operation; Python's default ASCII encoding will be used, so characters greater
+than 127 will cause an exception::
+
+ >>> s.find('Was\x9f')
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ UnicodeDecodeError: 'ascii' codec can't decode byte 0x9f in position 3: ordinal not in range(128)
+ >>> s.find(u'Was\x9f')
+ -1
+
+Much Python code that operates on strings will therefore work with Unicode
+strings without requiring any changes to the code. (Input and output code needs
+more updating for Unicode; more on this later.)
+
+Another important method is ``.encode([encoding], [errors='strict'])``, which
+returns an 8-bit string version of the Unicode string, encoded in the requested
+encoding. The ``errors`` parameter is the same as the parameter of the
+``unicode()`` constructor, with one additional possibility; as well as 'strict',
+'ignore', and 'replace', you can also pass 'xmlcharrefreplace' which uses XML's
+character references. The following example shows the different results::
+
+ >>> u = unichr(40960) + u'abcd' + unichr(1972)
+ >>> u.encode('utf-8')
+ '\xea\x80\x80abcd\xde\xb4'
+ >>> u.encode('ascii')
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ UnicodeEncodeError: 'ascii' codec can't encode character '\ua000' in position 0: ordinal not in range(128)
+ >>> u.encode('ascii', 'ignore')
+ 'abcd'
+ >>> u.encode('ascii', 'replace')
+ '?abcd?'
+ >>> u.encode('ascii', 'xmlcharrefreplace')
+ '&#40960;abcd&#1972;'
+
+Python's 8-bit strings have a ``.decode([encoding], [errors])`` method that
+interprets the string using the given encoding::
+
+ >>> u = unichr(40960) + u'abcd' + unichr(1972) # Assemble a string
+ >>> utf8_version = u.encode('utf-8') # Encode as UTF-8
+ >>> type(utf8_version), utf8_version
+ (<type 'str'>, '\xea\x80\x80abcd\xde\xb4')
+ >>> u2 = utf8_version.decode('utf-8') # Decode using UTF-8
+ >>> u == u2 # The two strings match
+ True
+
+The low-level routines for registering and accessing the available encodings are
+found in the :mod:`codecs` module. However, the encoding and decoding functions
+returned by this module are usually more low-level than is comfortable, so I'm
+not going to describe the :mod:`codecs` module here. If you need to implement a
+completely new encoding, you'll need to learn about the :mod:`codecs` module
+interfaces, but implementing encodings is a specialized task that also won't be
+covered here. Consult the Python documentation to learn more about this module.
+
+The most commonly used part of the :mod:`codecs` module is the
+:func:`codecs.open` function which will be discussed in the section on input and
+output.
+
+
+Unicode Literals in Python Source Code
+--------------------------------------
+
+In Python source code, Unicode literals are written as strings prefixed with the
+'u' or 'U' character: ``u'abcdefghijk'``. Specific code points can be written
+using the ``\u`` escape sequence, which is followed by four hex digits giving
+the code point. The ``\U`` escape sequence is similar, but expects 8 hex
+digits, not 4.
+
+Unicode literals can also use the same escape sequences as 8-bit strings,
+including ``\x``, but ``\x`` only takes two hex digits so it can't express an
+arbitrary code point. Octal escapes can go up to U+01ff, which is octal 777.
+
+::
+
+ >>> s = u"a\xac\u1234\u20ac\U00008000"
+ ^^^^ two-digit hex escape
+ ^^^^^^ four-digit Unicode escape
+ ^^^^^^^^^^ eight-digit Unicode escape
+ >>> for c in s: print ord(c),
+ ...
+ 97 172 4660 8364 32768
+
+Using escape sequences for code points greater than 127 is fine in small doses,
+but becomes an annoyance if you're using many accented characters, as you would
+in a program with messages in French or some other accent-using language. You
+can also assemble strings using the :func:`unichr` built-in function, but this is
+even more tedious.
+
+Ideally, you'd want to be able to write literals in your language's natural
+encoding. You could then edit Python source code with your favorite editor
+which would display the accented characters naturally, and have the right
+characters used at runtime.
+
+Python supports writing Unicode literals in any encoding, but you have to
+declare the encoding being used. This is done by including a special comment as
+either the first or second line of the source file::
+
+ #!/usr/bin/env python
+ # -*- coding: latin-1 -*-
+
+ u = u'abcdé'
+ print ord(u[-1])
+
+The syntax is inspired by Emacs's notation for specifying variables local to a
+file. Emacs supports many different variables, but Python only supports
+'coding'. The ``-*-`` symbols indicate that the comment is special; within
+them, you must supply the name ``coding`` and the name of your chosen encoding,
+separated by ``':'``.
+
+If you don't include such a comment, the default encoding used will be ASCII.
+Versions of Python before 2.4 were Euro-centric and assumed Latin-1 as a default
+encoding for string literals; in Python 2.4, characters greater than 127 still
+work but result in a warning. For example, the following program has no
+encoding declaration::
+
+ #!/usr/bin/env python
+ u = u'abcdé'
+ print ord(u[-1])
+
+When you run it with Python 2.4, it will output the following warning::
+
+ amk:~$ python p263.py
+ sys:1: DeprecationWarning: Non-ASCII character '\xe9'
+ in file p263.py on line 2, but no encoding declared;
+ see http://www.python.org/peps/pep-0263.html for details
+
+
+Unicode Properties
+------------------
+
+The Unicode specification includes a database of information about code points.
+For each code point that's defined, the information includes the character's
+name, its category, the numeric value if applicable (Unicode has characters
+representing the Roman numerals and fractions such as one-third and
+four-fifths). There are also properties related to the code point's use in
+bidirectional text and other display-related properties.
+
+The following program displays some information about several characters, and
+prints the numeric value of one particular character::
+
+ import unicodedata
+
+ u = unichr(233) + unichr(0x0bf2) + unichr(3972) + unichr(6000) + unichr(13231)
+
+ for i, c in enumerate(u):
+ print i, '%04x' % ord(c), unicodedata.category(c),
+ print unicodedata.name(c)
+
+ # Get numeric value of second character
+ print unicodedata.numeric(u[1])
+
+When run, this prints::
+
+ 0 00e9 Ll LATIN SMALL LETTER E WITH ACUTE
+ 1 0bf2 No TAMIL NUMBER ONE THOUSAND
+ 2 0f84 Mn TIBETAN MARK HALANTA
+ 3 1770 Lo TAGBANWA LETTER SA
+ 4 33af So SQUARE RAD OVER S SQUARED
+ 1000.0
+
+The category codes are abbreviations describing the nature of the character.
+These are grouped into categories such as "Letter", "Number", "Punctuation", or
+"Symbol", which in turn are broken up into subcategories. To take the codes
+from the above output, ``'Ll'`` means 'Letter, lowercase', ``'No'`` means
+"Number, other", ``'Mn'`` is "Mark, nonspacing", and ``'So'`` is "Symbol,
+other". See
+<http://www.unicode.org/Public/UNIDATA/UCD.html#General_Category_Values> for a
+list of category codes.
+
+References
+----------
+
+The Unicode and 8-bit string types are described in the Python library reference
+at :ref:`typesseq`.
+
+The documentation for the :mod:`unicodedata` module.
+
+The documentation for the :mod:`codecs` module.
+
+Marc-André Lemburg gave a presentation at EuroPython 2002 titled "Python and
+Unicode". A PDF version of his slides is available at
+<http://www.egenix.com/files/python/Unicode-EPC2002-Talk.pdf>, and is an
+excellent overview of the design of Python's Unicode features.
+
+
+Reading and Writing Unicode Data
+================================
+
+Once you've written some code that works with Unicode data, the next problem is
+input/output. How do you get Unicode strings into your program, and how do you
+convert Unicode into a form suitable for storage or transmission?
+
+It's possible that you may not need to do anything depending on your input
+sources and output destinations; you should check whether the libraries used in
+your application support Unicode natively. XML parsers often return Unicode
+data, for example. Many relational databases also support Unicode-valued
+columns and can return Unicode values from an SQL query.
+
+Unicode data is usually converted to a particular encoding before it gets
+written to disk or sent over a socket. It's possible to do all the work
+yourself: open a file, read an 8-bit string from it, and convert the string with
+``unicode(str, encoding)``. However, the manual approach is not recommended.
+
+One problem is the multi-byte nature of encodings; one Unicode character can be
+represented by several bytes. If you want to read the file in arbitrary-sized
+chunks (say, 1K or 4K), you need to write error-handling code to catch the case
+where only part of the bytes encoding a single Unicode character are read at the
+end of a chunk. One solution would be to read the entire file into memory and
+then perform the decoding, but that prevents you from working with files that
+are extremely large; if you need to read a 2Gb file, you need 2Gb of RAM.
+(More, really, since for at least a moment you'd need to have both the encoded
+string and its Unicode version in memory.)
+
+The solution would be to use the low-level decoding interface to catch the case
+of partial coding sequences. The work of implementing this has already been
+done for you: the :mod:`codecs` module includes a version of the :func:`open`
+function that returns a file-like object that assumes the file's contents are in
+a specified encoding and accepts Unicode parameters for methods such as
+``.read()`` and ``.write()``.
+
+The function's parameters are ``open(filename, mode='rb', encoding=None,
+errors='strict', buffering=1)``. ``mode`` can be ``'r'``, ``'w'``, or ``'a'``,
+just like the corresponding parameter to the regular built-in ``open()``
+function; add a ``'+'`` to update the file. ``buffering`` is similarly parallel
+to the standard function's parameter. ``encoding`` is a string giving the
+encoding to use; if it's left as ``None``, a regular Python file object that
+accepts 8-bit strings is returned. Otherwise, a wrapper object is returned, and
+data written to or read from the wrapper object will be converted as needed.
+``errors`` specifies the action for encoding errors and can be one of the usual
+values of 'strict', 'ignore', and 'replace'.
+
+Reading Unicode from a file is therefore simple::
+
+ import codecs
+ f = codecs.open('unicode.rst', encoding='utf-8')
+ for line in f:
+ print repr(line)
+
+It's also possible to open files in update mode, allowing both reading and
+writing::
+
+ f = codecs.open('test', encoding='utf-8', mode='w+')
+ f.write(u'\u4500 blah blah blah\n')
+ f.seek(0)
+ print repr(f.readline()[:1])
+ f.close()
+
+Unicode character U+FEFF is used as a byte-order mark (BOM), and is often
+written as the first character of a file in order to assist with autodetection
+of the file's byte ordering. Some encodings, such as UTF-16, expect a BOM to be
+present at the start of a file; when such an encoding is used, the BOM will be
+automatically written as the first character and will be silently dropped when
+the file is read. There are variants of these encodings, such as 'utf-16-le'
+and 'utf-16-be' for little-endian and big-endian encodings, that specify one
+particular byte ordering and don't skip the BOM.
+
+
+Unicode filenames
+-----------------
+
+Most of the operating systems in common use today support filenames that contain
+arbitrary Unicode characters. Usually this is implemented by converting the
+Unicode string into some encoding that varies depending on the system. For
+example, MacOS X uses UTF-8 while Windows uses a configurable encoding; on
+Windows, Python uses the name "mbcs" to refer to whatever the currently
+configured encoding is. On Unix systems, there will only be a filesystem
+encoding if you've set the ``LANG`` or ``LC_CTYPE`` environment variables; if
+you haven't, the default encoding is ASCII.
+
+The :func:`sys.getfilesystemencoding` function returns the encoding to use on
+your current system, in case you want to do the encoding manually, but there's
+not much reason to bother. When opening a file for reading or writing, you can
+usually just provide the Unicode string as the filename, and it will be
+automatically converted to the right encoding for you::
+
+ filename = u'filename\u4500abc'
+ f = open(filename, 'w')
+ f.write('blah\n')
+ f.close()
+
+Functions in the :mod:`os` module such as :func:`os.stat` will also accept Unicode
+filenames.
+
+:func:`os.listdir`, which returns filenames, raises an issue: should it return
+the Unicode version of filenames, or should it return 8-bit strings containing
+the encoded versions? :func:`os.listdir` will do both, depending on whether you
+provided the directory path as an 8-bit string or a Unicode string. If you pass
+a Unicode string as the path, filenames will be decoded using the filesystem's
+encoding and a list of Unicode strings will be returned, while passing an 8-bit
+path will return the 8-bit versions of the filenames. For example, assuming the
+default filesystem encoding is UTF-8, running the following program::
+
+ fn = u'filename\u4500abc'
+ f = open(fn, 'w')
+ f.close()
+
+ import os
+ print os.listdir('.')
+ print os.listdir(u'.')
+
+will produce the following output::
+
+ amk:~$ python t.py
+ ['.svn', 'filename\xe4\x94\x80abc', ...]
+ [u'.svn', u'filename\u4500abc', ...]
+
+The first list contains UTF-8-encoded filenames, and the second list contains
+the Unicode versions.
+
+
+
+Tips for Writing Unicode-aware Programs
+---------------------------------------
+
+This section provides some suggestions on writing software that deals with
+Unicode.
+
+The most important tip is:
+
+ Software should only work with Unicode strings internally, converting to a
+ particular encoding on output.
+
+If you attempt to write processing functions that accept both Unicode and 8-bit
+strings, you will find your program vulnerable to bugs wherever you combine the
+two different kinds of strings. Python's default encoding is ASCII, so whenever
+a character with an ASCII value > 127 is in the input data, you'll get a
+:exc:`UnicodeDecodeError` because that character can't be handled by the ASCII
+encoding.
+
+It's easy to miss such problems if you only test your software with data that
+doesn't contain any accents; everything will seem to work, but there's actually
+a bug in your program waiting for the first user who attempts to use characters
+> 127. A second tip, therefore, is:
+
+ Include characters > 127 and, even better, characters > 255 in your test
+ data.
+
+When using data coming from a web browser or some other untrusted source, a
+common technique is to check for illegal characters in a string before using the
+string in a generated command line or storing it in a database. If you're doing
+this, be careful to check the string once it's in the form that will be used or
+stored; it's possible for encodings to be used to disguise characters. This is
+especially true if the input data also specifies the encoding; many encodings
+leave the commonly checked-for characters alone, but Python includes some
+encodings such as ``'base64'`` that modify every single character.
+
+For example, let's say you have a content management system that takes a Unicode
+filename, and you want to disallow paths with a '/' character. You might write
+this code::
+
+ def read_file (filename, encoding):
+ if '/' in filename:
+ raise ValueError("'/' not allowed in filenames")
+ unicode_name = filename.decode(encoding)
+ f = open(unicode_name, 'r')
+ # ... return contents of file ...
+
+However, if an attacker could specify the ``'base64'`` encoding, they could pass
+``'L2V0Yy9wYXNzd2Q='``, which is the base-64 encoded form of the string
+``'/etc/passwd'``, to read a system file. The above code looks for ``'/'``
+characters in the encoded form and misses the dangerous character in the
+resulting decoded form.
+
+References
+----------
+
+The PDF slides for Marc-André Lemburg's presentation "Writing Unicode-aware
+Applications in Python" are available at
+<http://www.egenix.com/files/python/LSM2005-Developing-Unicode-aware-applications-in-Python.pdf>
+and discuss questions of character encodings as well as how to internationalize
+and localize an application.
+
+
+Revision History and Acknowledgements
+=====================================
+
+Thanks to the following people who have noted errors or offered suggestions on
+this article: Nicholas Bastin, Marius Gedminas, Kent Johnson, Ken Krugler,
+Marc-André Lemburg, Martin von Löwis, Chad Whitacre.
+
+Version 1.0: posted August 5 2005.
+
+Version 1.01: posted August 7 2005. Corrects factual and markup errors; adds
+several links.
+
+Version 1.02: posted August 16 2005. Corrects factual errors.
+
+
+.. comment Additional topic: building Python w/ UCS2 or UCS4 support
+.. comment Describe obscure -U switch somewhere?
+.. comment Describe use of codecs.StreamRecoder and StreamReaderWriter
+
+.. comment
+ Original outline:
+
+ - [ ] Unicode introduction
+ - [ ] ASCII
+ - [ ] Terms
+ - [ ] Character
+ - [ ] Code point
+ - [ ] Encodings
+ - [ ] Common encodings: ASCII, Latin-1, UTF-8
+ - [ ] Unicode Python type
+ - [ ] Writing unicode literals
+ - [ ] Obscurity: -U switch
+ - [ ] Built-ins
+ - [ ] unichr()
+ - [ ] ord()
+ - [ ] unicode() constructor
+ - [ ] Unicode type
+ - [ ] encode(), decode() methods
+ - [ ] Unicodedata module for character properties
+ - [ ] I/O
+ - [ ] Reading/writing Unicode data into files
+ - [ ] Byte-order marks
+ - [ ] Unicode filenames
+ - [ ] Writing Unicode programs
+ - [ ] Do everything in Unicode
+ - [ ] Declaring source code encodings (PEP 263)
+ - [ ] Other issues
+ - [ ] Building Python (UCS2, UCS4)
diff --git a/Doc/howto/urllib2.rst b/Doc/howto/urllib2.rst
new file mode 100644
index 0000000000..dc20b02d20
--- /dev/null
+++ b/Doc/howto/urllib2.rst
@@ -0,0 +1,578 @@
+************************************************
+ HOWTO Fetch Internet Resources Using urllib2
+************************************************
+
+:Author: `Michael Foord <http://www.voidspace.org.uk/python/index.shtml>`_
+
+.. note::
+
+ There is an French translation of an earlier revision of this
+ HOWTO, available at `urllib2 - Le Manuel manquant
+ <http://www.voidspace/python/articles/urllib2_francais.shtml>`_.
+
+
+
+Introduction
+============
+
+.. sidebar:: Related Articles
+
+ You may also find useful the following article on fetching web resources
+ with Python :
+
+ * `Basic Authentication <http://www.voidspace.org.uk/python/articles/authentication.shtml>`_
+
+ A tutorial on *Basic Authentication*, with examples in Python.
+
+**urllib2** is a `Python <http://www.python.org>`_ module for fetching URLs
+(Uniform Resource Locators). It offers a very simple interface, in the form of
+the *urlopen* function. This is capable of fetching URLs using a variety of
+different protocols. It also offers a slightly more complex interface for
+handling common situations - like basic authentication, cookies, proxies and so
+on. These are provided by objects called handlers and openers.
+
+urllib2 supports fetching URLs for many "URL schemes" (identified by the string
+before the ":" in URL - for example "ftp" is the URL scheme of
+"ftp://python.org/") using their associated network protocols (e.g. FTP, HTTP).
+This tutorial focuses on the most common case, HTTP.
+
+For straightforward situations *urlopen* is very easy to use. But as soon as you
+encounter errors or non-trivial cases when opening HTTP URLs, you will need some
+understanding of the HyperText Transfer Protocol. The most comprehensive and
+authoritative reference to HTTP is :rfc:`2616`. This is a technical document and
+not intended to be easy to read. This HOWTO aims to illustrate using *urllib2*,
+with enough detail about HTTP to help you through. It is not intended to replace
+the :mod:`urllib2` docs, but is supplementary to them.
+
+
+Fetching URLs
+=============
+
+The simplest way to use urllib2 is as follows::
+
+ import urllib2
+ response = urllib2.urlopen('http://python.org/')
+ html = response.read()
+
+Many uses of urllib2 will be that simple (note that instead of an 'http:' URL we
+could have used an URL starting with 'ftp:', 'file:', etc.). However, it's the
+purpose of this tutorial to explain the more complicated cases, concentrating on
+HTTP.
+
+HTTP is based on requests and responses - the client makes requests and servers
+send responses. urllib2 mirrors this with a ``Request`` object which represents
+the HTTP request you are making. In its simplest form you create a Request
+object that specifies the URL you want to fetch. Calling ``urlopen`` with this
+Request object returns a response object for the URL requested. This response is
+a file-like object, which means you can for example call ``.read()`` on the
+response::
+
+ import urllib2
+
+ req = urllib2.Request('http://www.voidspace.org.uk')
+ response = urllib2.urlopen(req)
+ the_page = response.read()
+
+Note that urllib2 makes use of the same Request interface to handle all URL
+schemes. For example, you can make an FTP request like so::
+
+ req = urllib2.Request('ftp://example.com/')
+
+In the case of HTTP, there are two extra things that Request objects allow you
+to do: First, you can pass data to be sent to the server. Second, you can pass
+extra information ("metadata") *about* the data or the about request itself, to
+the server - this information is sent as HTTP "headers". Let's look at each of
+these in turn.
+
+Data
+----
+
+Sometimes you want to send data to a URL (often the URL will refer to a CGI
+(Common Gateway Interface) script [#]_ or other web application). With HTTP,
+this is often done using what's known as a **POST** request. This is often what
+your browser does when you submit a HTML form that you filled in on the web. Not
+all POSTs have to come from forms: you can use a POST to transmit arbitrary data
+to your own application. In the common case of HTML forms, the data needs to be
+encoded in a standard way, and then passed to the Request object as the ``data``
+argument. The encoding is done using a function from the ``urllib`` library
+*not* from ``urllib2``. ::
+
+ import urllib
+ import urllib2
+
+ url = 'http://www.someserver.com/cgi-bin/register.cgi'
+ values = {'name' : 'Michael Foord',
+ 'location' : 'Northampton',
+ 'language' : 'Python' }
+
+ data = urllib.urlencode(values)
+ req = urllib2.Request(url, data)
+ response = urllib2.urlopen(req)
+ the_page = response.read()
+
+Note that other encodings are sometimes required (e.g. for file upload from HTML
+forms - see `HTML Specification, Form Submission
+<http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13>`_ for more
+details).
+
+If you do not pass the ``data`` argument, urllib2 uses a **GET** request. One
+way in which GET and POST requests differ is that POST requests often have
+"side-effects": they change the state of the system in some way (for example by
+placing an order with the website for a hundredweight of tinned spam to be
+delivered to your door). Though the HTTP standard makes it clear that POSTs are
+intended to *always* cause side-effects, and GET requests *never* to cause
+side-effects, nothing prevents a GET request from having side-effects, nor a
+POST requests from having no side-effects. Data can also be passed in an HTTP
+GET request by encoding it in the URL itself.
+
+This is done as follows::
+
+ >>> import urllib2
+ >>> import urllib
+ >>> data = {}
+ >>> data['name'] = 'Somebody Here'
+ >>> data['location'] = 'Northampton'
+ >>> data['language'] = 'Python'
+ >>> url_values = urllib.urlencode(data)
+ >>> print url_values
+ name=Somebody+Here&language=Python&location=Northampton
+ >>> url = 'http://www.example.com/example.cgi'
+ >>> full_url = url + '?' + url_values
+ >>> data = urllib2.open(full_url)
+
+Notice that the full URL is created by adding a ``?`` to the URL, followed by
+the encoded values.
+
+Headers
+-------
+
+We'll discuss here one particular HTTP header, to illustrate how to add headers
+to your HTTP request.
+
+Some websites [#]_ dislike being browsed by programs, or send different versions
+to different browsers [#]_ . By default urllib2 identifies itself as
+``Python-urllib/x.y`` (where ``x`` and ``y`` are the major and minor version
+numbers of the Python release,
+e.g. ``Python-urllib/2.5``), which may confuse the site, or just plain
+not work. The way a browser identifies itself is through the
+``User-Agent`` header [#]_. When you create a Request object you can
+pass a dictionary of headers in. The following example makes the same
+request as above, but identifies itself as a version of Internet
+Explorer [#]_. ::
+
+ import urllib
+ import urllib2
+
+ url = 'http://www.someserver.com/cgi-bin/register.cgi'
+ user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
+ values = {'name' : 'Michael Foord',
+ 'location' : 'Northampton',
+ 'language' : 'Python' }
+ headers = { 'User-Agent' : user_agent }
+
+ data = urllib.urlencode(values)
+ req = urllib2.Request(url, data, headers)
+ response = urllib2.urlopen(req)
+ the_page = response.read()
+
+The response also has two useful methods. See the section on `info and geturl`_
+which comes after we have a look at what happens when things go wrong.
+
+
+Handling Exceptions
+===================
+
+*urlopen* raises ``URLError`` when it cannot handle a response (though as usual
+with Python APIs, builtin exceptions such as ValueError, TypeError etc. may also
+be raised).
+
+``HTTPError`` is the subclass of ``URLError`` raised in the specific case of
+HTTP URLs.
+
+URLError
+--------
+
+Often, URLError is raised because there is no network connection (no route to
+the specified server), or the specified server doesn't exist. In this case, the
+exception raised will have a 'reason' attribute, which is a tuple containing an
+error code and a text error message.
+
+e.g. ::
+
+ >>> req = urllib2.Request('http://www.pretend_server.org')
+ >>> try: urllib2.urlopen(req)
+ >>> except URLError, e:
+ >>> print e.reason
+ >>>
+ (4, 'getaddrinfo failed')
+
+
+HTTPError
+---------
+
+Every HTTP response from the server contains a numeric "status code". Sometimes
+the status code indicates that the server is unable to fulfil the request. The
+default handlers will handle some of these responses for you (for example, if
+the response is a "redirection" that requests the client fetch the document from
+a different URL, urllib2 will handle that for you). For those it can't handle,
+urlopen will raise an ``HTTPError``. Typical errors include '404' (page not
+found), '403' (request forbidden), and '401' (authentication required).
+
+See section 10 of RFC 2616 for a reference on all the HTTP error codes.
+
+The ``HTTPError`` instance raised will have an integer 'code' attribute, which
+corresponds to the error sent by the server.
+
+Error Codes
+~~~~~~~~~~~
+
+Because the default handlers handle redirects (codes in the 300 range), and
+codes in the 100-299 range indicate success, you will usually only see error
+codes in the 400-599 range.
+
+``BaseHTTPServer.BaseHTTPRequestHandler.responses`` is a useful dictionary of
+response codes in that shows all the response codes used by RFC 2616. The
+dictionary is reproduced here for convenience ::
+
+ # Table mapping response codes to messages; entries have the
+ # form {code: (shortmessage, longmessage)}.
+ responses = {
+ 100: ('Continue', 'Request received, please continue'),
+ 101: ('Switching Protocols',
+ 'Switching to new protocol; obey Upgrade header'),
+
+ 200: ('OK', 'Request fulfilled, document follows'),
+ 201: ('Created', 'Document created, URL follows'),
+ 202: ('Accepted',
+ 'Request accepted, processing continues off-line'),
+ 203: ('Non-Authoritative Information', 'Request fulfilled from cache'),
+ 204: ('No Content', 'Request fulfilled, nothing follows'),
+ 205: ('Reset Content', 'Clear input form for further input.'),
+ 206: ('Partial Content', 'Partial content follows.'),
+
+ 300: ('Multiple Choices',
+ 'Object has several resources -- see URI list'),
+ 301: ('Moved Permanently', 'Object moved permanently -- see URI list'),
+ 302: ('Found', 'Object moved temporarily -- see URI list'),
+ 303: ('See Other', 'Object moved -- see Method and URL list'),
+ 304: ('Not Modified',
+ 'Document has not changed since given time'),
+ 305: ('Use Proxy',
+ 'You must use proxy specified in Location to access this '
+ 'resource.'),
+ 307: ('Temporary Redirect',
+ 'Object moved temporarily -- see URI list'),
+
+ 400: ('Bad Request',
+ 'Bad request syntax or unsupported method'),
+ 401: ('Unauthorized',
+ 'No permission -- see authorization schemes'),
+ 402: ('Payment Required',
+ 'No payment -- see charging schemes'),
+ 403: ('Forbidden',
+ 'Request forbidden -- authorization will not help'),
+ 404: ('Not Found', 'Nothing matches the given URI'),
+ 405: ('Method Not Allowed',
+ 'Specified method is invalid for this server.'),
+ 406: ('Not Acceptable', 'URI not available in preferred format.'),
+ 407: ('Proxy Authentication Required', 'You must authenticate with '
+ 'this proxy before proceeding.'),
+ 408: ('Request Timeout', 'Request timed out; try again later.'),
+ 409: ('Conflict', 'Request conflict.'),
+ 410: ('Gone',
+ 'URI no longer exists and has been permanently removed.'),
+ 411: ('Length Required', 'Client must specify Content-Length.'),
+ 412: ('Precondition Failed', 'Precondition in headers is false.'),
+ 413: ('Request Entity Too Large', 'Entity is too large.'),
+ 414: ('Request-URI Too Long', 'URI is too long.'),
+ 415: ('Unsupported Media Type', 'Entity body in unsupported format.'),
+ 416: ('Requested Range Not Satisfiable',
+ 'Cannot satisfy request range.'),
+ 417: ('Expectation Failed',
+ 'Expect condition could not be satisfied.'),
+
+ 500: ('Internal Server Error', 'Server got itself in trouble'),
+ 501: ('Not Implemented',
+ 'Server does not support this operation'),
+ 502: ('Bad Gateway', 'Invalid responses from another server/proxy.'),
+ 503: ('Service Unavailable',
+ 'The server cannot process the request due to a high load'),
+ 504: ('Gateway Timeout',
+ 'The gateway server did not receive a timely response'),
+ 505: ('HTTP Version Not Supported', 'Cannot fulfill request.'),
+ }
+
+When an error is raised the server responds by returning an HTTP error code
+*and* an error page. You can use the ``HTTPError`` instance as a response on the
+page returned. This means that as well as the code attribute, it also has read,
+geturl, and info, methods. ::
+
+ >>> req = urllib2.Request('http://www.python.org/fish.html')
+ >>> try:
+ >>> urllib2.urlopen(req)
+ >>> except URLError, e:
+ >>> print e.code
+ >>> print e.read()
+ >>>
+ 404
+ <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
+ "http://www.w3.org/TR/html4/loose.dtd">
+ <?xml-stylesheet href="./css/ht2html.css"
+ type="text/css"?>
+ <html><head><title>Error 404: File Not Found</title>
+ ...... etc...
+
+Wrapping it Up
+--------------
+
+So if you want to be prepared for ``HTTPError`` *or* ``URLError`` there are two
+basic approaches. I prefer the second approach.
+
+Number 1
+~~~~~~~~
+
+::
+
+
+ from urllib2 import Request, urlopen, URLError, HTTPError
+ req = Request(someurl)
+ try:
+ response = urlopen(req)
+ except HTTPError, e:
+ print 'The server couldn\'t fulfill the request.'
+ print 'Error code: ', e.code
+ except URLError, e:
+ print 'We failed to reach a server.'
+ print 'Reason: ', e.reason
+ else:
+ # everything is fine
+
+
+.. note::
+
+ The ``except HTTPError`` *must* come first, otherwise ``except URLError``
+ will *also* catch an ``HTTPError``.
+
+Number 2
+~~~~~~~~
+
+::
+
+ from urllib2 import Request, urlopen, URLError
+ req = Request(someurl)
+ try:
+ response = urlopen(req)
+ except URLError, e:
+ if hasattr(e, 'reason'):
+ print 'We failed to reach a server.'
+ print 'Reason: ', e.reason
+ elif hasattr(e, 'code'):
+ print 'The server couldn\'t fulfill the request.'
+ print 'Error code: ', e.code
+ else:
+ # everything is fine
+
+
+info and geturl
+===============
+
+The response returned by urlopen (or the ``HTTPError`` instance) has two useful
+methods ``info`` and ``geturl``.
+
+**geturl** - this returns the real URL of the page fetched. This is useful
+because ``urlopen`` (or the opener object used) may have followed a
+redirect. The URL of the page fetched may not be the same as the URL requested.
+
+**info** - this returns a dictionary-like object that describes the page
+fetched, particularly the headers sent by the server. It is currently an
+``httplib.HTTPMessage`` instance.
+
+Typical headers include 'Content-length', 'Content-type', and so on. See the
+`Quick Reference to HTTP Headers <http://www.cs.tut.fi/~jkorpela/http.html>`_
+for a useful listing of HTTP headers with brief explanations of their meaning
+and use.
+
+
+Openers and Handlers
+====================
+
+When you fetch a URL you use an opener (an instance of the perhaps
+confusingly-named :class:`urllib2.OpenerDirector`). Normally we have been using
+the default opener - via ``urlopen`` - but you can create custom
+openers. Openers use handlers. All the "heavy lifting" is done by the
+handlers. Each handler knows how to open URLs for a particular URL scheme (http,
+ftp, etc.), or how to handle an aspect of URL opening, for example HTTP
+redirections or HTTP cookies.
+
+You will want to create openers if you want to fetch URLs with specific handlers
+installed, for example to get an opener that handles cookies, or to get an
+opener that does not handle redirections.
+
+To create an opener, instantiate an ``OpenerDirector``, and then call
+``.add_handler(some_handler_instance)`` repeatedly.
+
+Alternatively, you can use ``build_opener``, which is a convenience function for
+creating opener objects with a single function call. ``build_opener`` adds
+several handlers by default, but provides a quick way to add more and/or
+override the default handlers.
+
+Other sorts of handlers you might want to can handle proxies, authentication,
+and other common but slightly specialised situations.
+
+``install_opener`` can be used to make an ``opener`` object the (global) default
+opener. This means that calls to ``urlopen`` will use the opener you have
+installed.
+
+Opener objects have an ``open`` method, which can be called directly to fetch
+urls in the same way as the ``urlopen`` function: there's no need to call
+``install_opener``, except as a convenience.
+
+
+Basic Authentication
+====================
+
+To illustrate creating and installing a handler we will use the
+``HTTPBasicAuthHandler``. For a more detailed discussion of this subject --
+including an explanation of how Basic Authentication works - see the `Basic
+Authentication Tutorial
+<http://www.voidspace.org.uk/python/articles/authentication.shtml>`_.
+
+When authentication is required, the server sends a header (as well as the 401
+error code) requesting authentication. This specifies the authentication scheme
+and a 'realm'. The header looks like : ``Www-authenticate: SCHEME
+realm="REALM"``.
+
+e.g. ::
+
+ Www-authenticate: Basic realm="cPanel Users"
+
+
+The client should then retry the request with the appropriate name and password
+for the realm included as a header in the request. This is 'basic
+authentication'. In order to simplify this process we can create an instance of
+``HTTPBasicAuthHandler`` and an opener to use this handler.
+
+The ``HTTPBasicAuthHandler`` uses an object called a password manager to handle
+the mapping of URLs and realms to passwords and usernames. If you know what the
+realm is (from the authentication header sent by the server), then you can use a
+``HTTPPasswordMgr``. Frequently one doesn't care what the realm is. In that
+case, it is convenient to use ``HTTPPasswordMgrWithDefaultRealm``. This allows
+you to specify a default username and password for a URL. This will be supplied
+in the absence of you providing an alternative combination for a specific
+realm. We indicate this by providing ``None`` as the realm argument to the
+``add_password`` method.
+
+The top-level URL is the first URL that requires authentication. URLs "deeper"
+than the URL you pass to .add_password() will also match. ::
+
+ # create a password manager
+ password_mgr = urllib2.HTTPPasswordMgrWithDefaultRealm()
+
+ # Add the username and password.
+ # If we knew the realm, we could use it instead of ``None``.
+ top_level_url = "http://example.com/foo/"
+ password_mgr.add_password(None, top_level_url, username, password)
+
+ handler = urllib2.HTTPBasicAuthHandler(password_mgr)
+
+ # create "opener" (OpenerDirector instance)
+ opener = urllib2.build_opener(handler)
+
+ # use the opener to fetch a URL
+ opener.open(a_url)
+
+ # Install the opener.
+ # Now all calls to urllib2.urlopen use our opener.
+ urllib2.install_opener(opener)
+
+.. note::
+
+ In the above example we only supplied our ``HHTPBasicAuthHandler`` to
+ ``build_opener``. By default openers have the handlers for normal situations
+ -- ``ProxyHandler``, ``UnknownHandler``, ``HTTPHandler``,
+ ``HTTPDefaultErrorHandler``, ``HTTPRedirectHandler``, ``FTPHandler``,
+ ``FileHandler``, ``HTTPErrorProcessor``.
+
+``top_level_url`` is in fact *either* a full URL (including the 'http:' scheme
+component and the hostname and optionally the port number)
+e.g. "http://example.com/" *or* an "authority" (i.e. the hostname,
+optionally including the port number) e.g. "example.com" or "example.com:8080"
+(the latter example includes a port number). The authority, if present, must
+NOT contain the "userinfo" component - for example "joe@password:example.com" is
+not correct.
+
+
+Proxies
+=======
+
+**urllib2** will auto-detect your proxy settings and use those. This is through
+the ``ProxyHandler`` which is part of the normal handler chain. Normally that's
+a good thing, but there are occasions when it may not be helpful [#]_. One way
+to do this is to setup our own ``ProxyHandler``, with no proxies defined. This
+is done using similar steps to setting up a `Basic Authentication`_ handler : ::
+
+ >>> proxy_support = urllib2.ProxyHandler({})
+ >>> opener = urllib2.build_opener(proxy_support)
+ >>> urllib2.install_opener(opener)
+
+.. note::
+
+ Currently ``urllib2`` *does not* support fetching of ``https`` locations
+ through a proxy. However, this can be enabled by extending urllib2 as
+ shown in the recipe [#]_.
+
+
+Sockets and Layers
+==================
+
+The Python support for fetching resources from the web is layered. urllib2 uses
+the httplib library, which in turn uses the socket library.
+
+As of Python 2.3 you can specify how long a socket should wait for a response
+before timing out. This can be useful in applications which have to fetch web
+pages. By default the socket module has *no timeout* and can hang. Currently,
+the socket timeout is not exposed at the httplib or urllib2 levels. However,
+you can set the default timeout globally for all sockets using ::
+
+ import socket
+ import urllib2
+
+ # timeout in seconds
+ timeout = 10
+ socket.setdefaulttimeout(timeout)
+
+ # this call to urllib2.urlopen now uses the default timeout
+ # we have set in the socket module
+ req = urllib2.Request('http://www.voidspace.org.uk')
+ response = urllib2.urlopen(req)
+
+
+-------
+
+
+Footnotes
+=========
+
+This document was reviewed and revised by John Lee.
+
+.. [#] For an introduction to the CGI protocol see
+ `Writing Web Applications in Python <http://www.pyzine.com/Issue008/Section_Articles/article_CGIOne.html>`_.
+.. [#] Like Google for example. The *proper* way to use google from a program
+ is to use `PyGoogle <http://pygoogle.sourceforge.net>`_ of course. See
+ `Voidspace Google <http://www.voidspace.org.uk/python/recipebook.shtml#google>`_
+ for some examples of using the Google API.
+.. [#] Browser sniffing is a very bad practise for website design - building
+ sites using web standards is much more sensible. Unfortunately a lot of
+ sites still send different versions to different browsers.
+.. [#] The user agent for MSIE 6 is
+ *'Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322)'*
+.. [#] For details of more HTTP request headers, see
+ `Quick Reference to HTTP Headers`_.
+.. [#] In my case I have to use a proxy to access the internet at work. If you
+ attempt to fetch *localhost* URLs through this proxy it blocks them. IE
+ is set to use the proxy, which urllib2 picks up on. In order to test
+ scripts with a localhost server, I have to prevent urllib2 from using
+ the proxy.
+.. [#] urllib2 opener for SSL proxy (CONNECT method): `ASPN Cookbook Recipe
+ <http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/456195>`_.
+
diff --git a/Doc/includes/email-dir.py b/Doc/includes/email-dir.py
new file mode 100644
index 0000000000..c04f57d641
--- /dev/null
+++ b/Doc/includes/email-dir.py
@@ -0,0 +1,115 @@
+#!/usr/bin/env python
+
+"""Send the contents of a directory as a MIME message."""
+
+import os
+import sys
+import smtplib
+# For guessing MIME type based on file name extension
+import mimetypes
+
+from optparse import OptionParser
+
+from email import encoders
+from email.message import Message
+from email.mime.audio import MIMEAudio
+from email.mime.base import MIMEBase
+from email.mime.image import MIMEImage
+from email.mime.multipart import MIMEMultipart
+from email.mime.text import MIMEText
+
+COMMASPACE = ', '
+
+
+def main():
+ parser = OptionParser(usage="""\
+Send the contents of a directory as a MIME message.
+
+Usage: %prog [options]
+
+Unless the -o option is given, the email is sent by forwarding to your local
+SMTP server, which then does the normal delivery process. Your local machine
+must be running an SMTP server.
+""")
+ parser.add_option('-d', '--directory',
+ type='string', action='store',
+ help="""Mail the contents of the specified directory,
+ otherwise use the current directory. Only the regular
+ files in the directory are sent, and we don't recurse to
+ subdirectories.""")
+ parser.add_option('-o', '--output',
+ type='string', action='store', metavar='FILE',
+ help="""Print the composed message to FILE instead of
+ sending the message to the SMTP server.""")
+ parser.add_option('-s', '--sender',
+ type='string', action='store', metavar='SENDER',
+ help='The value of the From: header (required)')
+ parser.add_option('-r', '--recipient',
+ type='string', action='append', metavar='RECIPIENT',
+ default=[], dest='recipients',
+ help='A To: header value (at least one required)')
+ opts, args = parser.parse_args()
+ if not opts.sender or not opts.recipients:
+ parser.print_help()
+ sys.exit(1)
+ directory = opts.directory
+ if not directory:
+ directory = '.'
+ # Create the enclosing (outer) message
+ outer = MIMEMultipart()
+ outer['Subject'] = 'Contents of directory %s' % os.path.abspath(directory)
+ outer['To'] = COMMASPACE.join(opts.recipients)
+ outer['From'] = opts.sender
+ outer.preamble = 'You will not see this in a MIME-aware mail reader.\n'
+
+ for filename in os.listdir(directory):
+ path = os.path.join(directory, filename)
+ if not os.path.isfile(path):
+ continue
+ # Guess the content type based on the file's extension. Encoding
+ # will be ignored, although we should check for simple things like
+ # gzip'd or compressed files.
+ ctype, encoding = mimetypes.guess_type(path)
+ if ctype is None or encoding is not None:
+ # No guess could be made, or the file is encoded (compressed), so
+ # use a generic bag-of-bits type.
+ ctype = 'application/octet-stream'
+ maintype, subtype = ctype.split('/', 1)
+ if maintype == 'text':
+ fp = open(path)
+ # Note: we should handle calculating the charset
+ msg = MIMEText(fp.read(), _subtype=subtype)
+ fp.close()
+ elif maintype == 'image':
+ fp = open(path, 'rb')
+ msg = MIMEImage(fp.read(), _subtype=subtype)
+ fp.close()
+ elif maintype == 'audio':
+ fp = open(path, 'rb')
+ msg = MIMEAudio(fp.read(), _subtype=subtype)
+ fp.close()
+ else:
+ fp = open(path, 'rb')
+ msg = MIMEBase(maintype, subtype)
+ msg.set_payload(fp.read())
+ fp.close()
+ # Encode the payload using Base64
+ encoders.encode_base64(msg)
+ # Set the filename parameter
+ msg.add_header('Content-Disposition', 'attachment', filename=filename)
+ outer.attach(msg)
+ # Now send or store the message
+ composed = outer.as_string()
+ if opts.output:
+ fp = open(opts.output, 'w')
+ fp.write(composed)
+ fp.close()
+ else:
+ s = smtplib.SMTP()
+ s.connect()
+ s.sendmail(opts.sender, opts.recipients, composed)
+ s.close()
+
+
+if __name__ == '__main__':
+ main()
diff --git a/Doc/includes/email-mime.py b/Doc/includes/email-mime.py
new file mode 100644
index 0000000000..5097253749
--- /dev/null
+++ b/Doc/includes/email-mime.py
@@ -0,0 +1,32 @@
+# Import smtplib for the actual sending function
+import smtplib
+
+# Here are the email package modules we'll need
+from email.mime.image import MIMEImage
+from email.mime.multipart import MIMEMultipart
+
+COMMASPACE = ', '
+
+# Create the container (outer) email message.
+msg = MIMEMultipart()
+msg['Subject'] = 'Our family reunion'
+# me == the sender's email address
+# family = the list of all recipients' email addresses
+msg['From'] = me
+msg['To'] = COMMASPACE.join(family)
+msg.preamble = 'Our family reunion'
+
+# Assume we know that the image files are all in PNG format
+for file in pngfiles:
+ # Open the files in binary mode. Let the MIMEImage class automatically
+ # guess the specific image type.
+ fp = open(file, 'rb')
+ img = MIMEImage(fp.read())
+ fp.close()
+ msg.attach(img)
+
+# Send the email via our own SMTP server.
+s = smtplib.SMTP()
+s.connect()
+s.sendmail(me, family, msg.as_string())
+s.close()
diff --git a/Doc/includes/email-simple.py b/Doc/includes/email-simple.py
new file mode 100644
index 0000000000..44152a4839
--- /dev/null
+++ b/Doc/includes/email-simple.py
@@ -0,0 +1,25 @@
+# Import smtplib for the actual sending function
+import smtplib
+
+# Import the email modules we'll need
+from email.mime.text import MIMEText
+
+# Open a plain text file for reading. For this example, assume that
+# the text file contains only ASCII characters.
+fp = open(textfile, 'rb')
+# Create a text/plain message
+msg = MIMEText(fp.read())
+fp.close()
+
+# me == the sender's email address
+# you == the recipient's email address
+msg['Subject'] = 'The contents of %s' % textfile
+msg['From'] = me
+msg['To'] = you
+
+# Send the message via our own SMTP server, but don't include the
+# envelope header.
+s = smtplib.SMTP()
+s.connect()
+s.sendmail(me, [you], msg.as_string())
+s.close()
diff --git a/Doc/includes/email-unpack.py b/Doc/includes/email-unpack.py
new file mode 100644
index 0000000000..e596b98176
--- /dev/null
+++ b/Doc/includes/email-unpack.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+
+"""Unpack a MIME message into a directory of files."""
+
+import os
+import sys
+import email
+import errno
+import mimetypes
+
+from optparse import OptionParser
+
+
+def main():
+ parser = OptionParser(usage="""\
+Unpack a MIME message into a directory of files.
+
+Usage: %prog [options] msgfile
+""")
+ parser.add_option('-d', '--directory',
+ type='string', action='store',
+ help="""Unpack the MIME message into the named
+ directory, which will be created if it doesn't already
+ exist.""")
+ opts, args = parser.parse_args()
+ if not opts.directory:
+ parser.print_help()
+ sys.exit(1)
+
+ try:
+ msgfile = args[0]
+ except IndexError:
+ parser.print_help()
+ sys.exit(1)
+
+ try:
+ os.mkdir(opts.directory)
+ except OSError as e:
+ # Ignore directory exists error
+ if e.errno != errno.EEXIST:
+ raise
+
+ fp = open(msgfile)
+ msg = email.message_from_file(fp)
+ fp.close()
+
+ counter = 1
+ for part in msg.walk():
+ # multipart/* are just containers
+ if part.get_content_maintype() == 'multipart':
+ continue
+ # Applications should really sanitize the given filename so that an
+ # email message can't be used to overwrite important files
+ filename = part.get_filename()
+ if not filename:
+ ext = mimetypes.guess_extension(part.get_type())
+ if not ext:
+ # Use a generic bag-of-bits extension
+ ext = '.bin'
+ filename = 'part-%03d%s' % (counter, ext)
+ counter += 1
+ fp = open(os.path.join(opts.directory, filename), 'wb')
+ fp.write(part.get_payload(decode=True))
+ fp.close()
+
+
+if __name__ == '__main__':
+ main()
diff --git a/Doc/includes/minidom-example.py b/Doc/includes/minidom-example.py
new file mode 100644
index 0000000000..c30c4e08a9
--- /dev/null
+++ b/Doc/includes/minidom-example.py
@@ -0,0 +1,64 @@
+import xml.dom.minidom
+
+document = """\
+<slideshow>
+<title>Demo slideshow</title>
+<slide><title>Slide title</title>
+<point>This is a demo</point>
+<point>Of a program for processing slides</point>
+</slide>
+
+<slide><title>Another demo slide</title>
+<point>It is important</point>
+<point>To have more than</point>
+<point>one slide</point>
+</slide>
+</slideshow>
+"""
+
+dom = xml.dom.minidom.parseString(document)
+
+def getText(nodelist):
+ rc = ""
+ for node in nodelist:
+ if node.nodeType == node.TEXT_NODE:
+ rc = rc + node.data
+ return rc
+
+def handleSlideshow(slideshow):
+ print "<html>"
+ handleSlideshowTitle(slideshow.getElementsByTagName("title")[0])
+ slides = slideshow.getElementsByTagName("slide")
+ handleToc(slides)
+ handleSlides(slides)
+ print "</html>"
+
+def handleSlides(slides):
+ for slide in slides:
+ handleSlide(slide)
+
+def handleSlide(slide):
+ handleSlideTitle(slide.getElementsByTagName("title")[0])
+ handlePoints(slide.getElementsByTagName("point"))
+
+def handleSlideshowTitle(title):
+ print "<title>%s</title>" % getText(title.childNodes)
+
+def handleSlideTitle(title):
+ print "<h2>%s</h2>" % getText(title.childNodes)
+
+def handlePoints(points):
+ print "<ul>"
+ for point in points:
+ handlePoint(point)
+ print "</ul>"
+
+def handlePoint(point):
+ print "<li>%s</li>" % getText(point.childNodes)
+
+def handleToc(slides):
+ for slide in slides:
+ title = slide.getElementsByTagName("title")[0]
+ print "<p>%s</p>" % getText(title.childNodes)
+
+handleSlideshow(dom)
diff --git a/Doc/includes/noddy.c b/Doc/includes/noddy.c
new file mode 100644
index 0000000000..ec2d669dd1
--- /dev/null
+++ b/Doc/includes/noddy.c
@@ -0,0 +1,54 @@
+#include <Python.h>
+
+typedef struct {
+ PyObject_HEAD
+ /* Type-specific fields go here. */
+} noddy_NoddyObject;
+
+static PyTypeObject noddy_NoddyType = {
+ PyObject_HEAD_INIT(NULL)
+ 0, /*ob_size*/
+ "noddy.Noddy", /*tp_name*/
+ sizeof(noddy_NoddyObject), /*tp_basicsize*/
+ 0, /*tp_itemsize*/
+ 0, /*tp_dealloc*/
+ 0, /*tp_print*/
+ 0, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+ 0, /*tp_as_number*/
+ 0, /*tp_as_sequence*/
+ 0, /*tp_as_mapping*/
+ 0, /*tp_hash */
+ 0, /*tp_call*/
+ 0, /*tp_str*/
+ 0, /*tp_getattro*/
+ 0, /*tp_setattro*/
+ 0, /*tp_as_buffer*/
+ Py_TPFLAGS_DEFAULT, /*tp_flags*/
+ "Noddy objects", /* tp_doc */
+};
+
+static PyMethodDef noddy_methods[] = {
+ {NULL} /* Sentinel */
+};
+
+#ifndef PyMODINIT_FUNC /* declarations for DLL import/export */
+#define PyMODINIT_FUNC void
+#endif
+PyMODINIT_FUNC
+initnoddy(void)
+{
+ PyObject* m;
+
+ noddy_NoddyType.tp_new = PyType_GenericNew;
+ if (PyType_Ready(&noddy_NoddyType) < 0)
+ return;
+
+ m = Py_InitModule3("noddy", noddy_methods,
+ "Example module that creates an extension type.");
+
+ Py_INCREF(&noddy_NoddyType);
+ PyModule_AddObject(m, "Noddy", (PyObject *)&noddy_NoddyType);
+}
diff --git a/Doc/includes/noddy2.c b/Doc/includes/noddy2.c
new file mode 100644
index 0000000000..2caf9855c6
--- /dev/null
+++ b/Doc/includes/noddy2.c
@@ -0,0 +1,190 @@
+#include <Python.h>
+#include "structmember.h"
+
+typedef struct {
+ PyObject_HEAD
+ PyObject *first; /* first name */
+ PyObject *last; /* last name */
+ int number;
+} Noddy;
+
+static void
+Noddy_dealloc(Noddy* self)
+{
+ Py_XDECREF(self->first);
+ Py_XDECREF(self->last);
+ self->ob_type->tp_free((PyObject*)self);
+}
+
+static PyObject *
+Noddy_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+ Noddy *self;
+
+ self = (Noddy *)type->tp_alloc(type, 0);
+ if (self != NULL) {
+ self->first = PyString_FromString("");
+ if (self->first == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->last = PyString_FromString("");
+ if (self->last == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->number = 0;
+ }
+
+ return (PyObject *)self;
+}
+
+static int
+Noddy_init(Noddy *self, PyObject *args, PyObject *kwds)
+{
+ PyObject *first=NULL, *last=NULL, *tmp;
+
+ static char *kwlist[] = {"first", "last", "number", NULL};
+
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
+ &first, &last,
+ &self->number))
+ return -1;
+
+ if (first) {
+ tmp = self->first;
+ Py_INCREF(first);
+ self->first = first;
+ Py_XDECREF(tmp);
+ }
+
+ if (last) {
+ tmp = self->last;
+ Py_INCREF(last);
+ self->last = last;
+ Py_XDECREF(tmp);
+ }
+
+ return 0;
+}
+
+
+static PyMemberDef Noddy_members[] = {
+ {"first", T_OBJECT_EX, offsetof(Noddy, first), 0,
+ "first name"},
+ {"last", T_OBJECT_EX, offsetof(Noddy, last), 0,
+ "last name"},
+ {"number", T_INT, offsetof(Noddy, number), 0,
+ "noddy number"},
+ {NULL} /* Sentinel */
+};
+
+static PyObject *
+Noddy_name(Noddy* self)
+{
+ static PyObject *format = NULL;
+ PyObject *args, *result;
+
+ if (format == NULL) {
+ format = PyString_FromString("%s %s");
+ if (format == NULL)
+ return NULL;
+ }
+
+ if (self->first == NULL) {
+ PyErr_SetString(PyExc_AttributeError, "first");
+ return NULL;
+ }
+
+ if (self->last == NULL) {
+ PyErr_SetString(PyExc_AttributeError, "last");
+ return NULL;
+ }
+
+ args = Py_BuildValue("OO", self->first, self->last);
+ if (args == NULL)
+ return NULL;
+
+ result = PyString_Format(format, args);
+ Py_DECREF(args);
+
+ return result;
+}
+
+static PyMethodDef Noddy_methods[] = {
+ {"name", (PyCFunction)Noddy_name, METH_NOARGS,
+ "Return the name, combining the first and last name"
+ },
+ {NULL} /* Sentinel */
+};
+
+static PyTypeObject NoddyType = {
+ PyObject_HEAD_INIT(NULL)
+ 0, /*ob_size*/
+ "noddy.Noddy", /*tp_name*/
+ sizeof(Noddy), /*tp_basicsize*/
+ 0, /*tp_itemsize*/
+ (destructor)Noddy_dealloc, /*tp_dealloc*/
+ 0, /*tp_print*/
+ 0, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+ 0, /*tp_as_number*/
+ 0, /*tp_as_sequence*/
+ 0, /*tp_as_mapping*/
+ 0, /*tp_hash */
+ 0, /*tp_call*/
+ 0, /*tp_str*/
+ 0, /*tp_getattro*/
+ 0, /*tp_setattro*/
+ 0, /*tp_as_buffer*/
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+ "Noddy objects", /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
+ Noddy_methods, /* tp_methods */
+ Noddy_members, /* tp_members */
+ 0, /* tp_getset */
+ 0, /* tp_base */
+ 0, /* tp_dict */
+ 0, /* tp_descr_get */
+ 0, /* tp_descr_set */
+ 0, /* tp_dictoffset */
+ (initproc)Noddy_init, /* tp_init */
+ 0, /* tp_alloc */
+ Noddy_new, /* tp_new */
+};
+
+static PyMethodDef module_methods[] = {
+ {NULL} /* Sentinel */
+};
+
+#ifndef PyMODINIT_FUNC /* declarations for DLL import/export */
+#define PyMODINIT_FUNC void
+#endif
+PyMODINIT_FUNC
+initnoddy2(void)
+{
+ PyObject* m;
+
+ if (PyType_Ready(&NoddyType) < 0)
+ return;
+
+ m = Py_InitModule3("noddy2", module_methods,
+ "Example module that creates an extension type.");
+
+ if (m == NULL)
+ return;
+
+ Py_INCREF(&NoddyType);
+ PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
+}
diff --git a/Doc/includes/noddy3.c b/Doc/includes/noddy3.c
new file mode 100644
index 0000000000..60260ada52
--- /dev/null
+++ b/Doc/includes/noddy3.c
@@ -0,0 +1,243 @@
+#include <Python.h>
+#include "structmember.h"
+
+typedef struct {
+ PyObject_HEAD
+ PyObject *first;
+ PyObject *last;
+ int number;
+} Noddy;
+
+static void
+Noddy_dealloc(Noddy* self)
+{
+ Py_XDECREF(self->first);
+ Py_XDECREF(self->last);
+ self->ob_type->tp_free((PyObject*)self);
+}
+
+static PyObject *
+Noddy_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+ Noddy *self;
+
+ self = (Noddy *)type->tp_alloc(type, 0);
+ if (self != NULL) {
+ self->first = PyString_FromString("");
+ if (self->first == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->last = PyString_FromString("");
+ if (self->last == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->number = 0;
+ }
+
+ return (PyObject *)self;
+}
+
+static int
+Noddy_init(Noddy *self, PyObject *args, PyObject *kwds)
+{
+ PyObject *first=NULL, *last=NULL, *tmp;
+
+ static char *kwlist[] = {"first", "last", "number", NULL};
+
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|SSi", kwlist,
+ &first, &last,
+ &self->number))
+ return -1;
+
+ if (first) {
+ tmp = self->first;
+ Py_INCREF(first);
+ self->first = first;
+ Py_DECREF(tmp);
+ }
+
+ if (last) {
+ tmp = self->last;
+ Py_INCREF(last);
+ self->last = last;
+ Py_DECREF(tmp);
+ }
+
+ return 0;
+}
+
+static PyMemberDef Noddy_members[] = {
+ {"number", T_INT, offsetof(Noddy, number), 0,
+ "noddy number"},
+ {NULL} /* Sentinel */
+};
+
+static PyObject *
+Noddy_getfirst(Noddy *self, void *closure)
+{
+ Py_INCREF(self->first);
+ return self->first;
+}
+
+static int
+Noddy_setfirst(Noddy *self, PyObject *value, void *closure)
+{
+ if (value == NULL) {
+ PyErr_SetString(PyExc_TypeError, "Cannot delete the first attribute");
+ return -1;
+ }
+
+ if (! PyString_Check(value)) {
+ PyErr_SetString(PyExc_TypeError,
+ "The first attribute value must be a string");
+ return -1;
+ }
+
+ Py_DECREF(self->first);
+ Py_INCREF(value);
+ self->first = value;
+
+ return 0;
+}
+
+static PyObject *
+Noddy_getlast(Noddy *self, void *closure)
+{
+ Py_INCREF(self->last);
+ return self->last;
+}
+
+static int
+Noddy_setlast(Noddy *self, PyObject *value, void *closure)
+{
+ if (value == NULL) {
+ PyErr_SetString(PyExc_TypeError, "Cannot delete the last attribute");
+ return -1;
+ }
+
+ if (! PyString_Check(value)) {
+ PyErr_SetString(PyExc_TypeError,
+ "The last attribute value must be a string");
+ return -1;
+ }
+
+ Py_DECREF(self->last);
+ Py_INCREF(value);
+ self->last = value;
+
+ return 0;
+}
+
+static PyGetSetDef Noddy_getseters[] = {
+ {"first",
+ (getter)Noddy_getfirst, (setter)Noddy_setfirst,
+ "first name",
+ NULL},
+ {"last",
+ (getter)Noddy_getlast, (setter)Noddy_setlast,
+ "last name",
+ NULL},
+ {NULL} /* Sentinel */
+};
+
+static PyObject *
+Noddy_name(Noddy* self)
+{
+ static PyObject *format = NULL;
+ PyObject *args, *result;
+
+ if (format == NULL) {
+ format = PyString_FromString("%s %s");
+ if (format == NULL)
+ return NULL;
+ }
+
+ args = Py_BuildValue("OO", self->first, self->last);
+ if (args == NULL)
+ return NULL;
+
+ result = PyString_Format(format, args);
+ Py_DECREF(args);
+
+ return result;
+}
+
+static PyMethodDef Noddy_methods[] = {
+ {"name", (PyCFunction)Noddy_name, METH_NOARGS,
+ "Return the name, combining the first and last name"
+ },
+ {NULL} /* Sentinel */
+};
+
+static PyTypeObject NoddyType = {
+ PyObject_HEAD_INIT(NULL)
+ 0, /*ob_size*/
+ "noddy.Noddy", /*tp_name*/
+ sizeof(Noddy), /*tp_basicsize*/
+ 0, /*tp_itemsize*/
+ (destructor)Noddy_dealloc, /*tp_dealloc*/
+ 0, /*tp_print*/
+ 0, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+ 0, /*tp_as_number*/
+ 0, /*tp_as_sequence*/
+ 0, /*tp_as_mapping*/
+ 0, /*tp_hash */
+ 0, /*tp_call*/
+ 0, /*tp_str*/
+ 0, /*tp_getattro*/
+ 0, /*tp_setattro*/
+ 0, /*tp_as_buffer*/
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+ "Noddy objects", /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
+ Noddy_methods, /* tp_methods */
+ Noddy_members, /* tp_members */
+ Noddy_getseters, /* tp_getset */
+ 0, /* tp_base */
+ 0, /* tp_dict */
+ 0, /* tp_descr_get */
+ 0, /* tp_descr_set */
+ 0, /* tp_dictoffset */
+ (initproc)Noddy_init, /* tp_init */
+ 0, /* tp_alloc */
+ Noddy_new, /* tp_new */
+};
+
+static PyMethodDef module_methods[] = {
+ {NULL} /* Sentinel */
+};
+
+#ifndef PyMODINIT_FUNC /* declarations for DLL import/export */
+#define PyMODINIT_FUNC void
+#endif
+PyMODINIT_FUNC
+initnoddy3(void)
+{
+ PyObject* m;
+
+ if (PyType_Ready(&NoddyType) < 0)
+ return;
+
+ m = Py_InitModule3("noddy3", module_methods,
+ "Example module that creates an extension type.");
+
+ if (m == NULL)
+ return;
+
+ Py_INCREF(&NoddyType);
+ PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
+}
diff --git a/Doc/includes/noddy4.c b/Doc/includes/noddy4.c
new file mode 100644
index 0000000000..878e0861d8
--- /dev/null
+++ b/Doc/includes/noddy4.c
@@ -0,0 +1,224 @@
+#include <Python.h>
+#include "structmember.h"
+
+typedef struct {
+ PyObject_HEAD
+ PyObject *first;
+ PyObject *last;
+ int number;
+} Noddy;
+
+static int
+Noddy_traverse(Noddy *self, visitproc visit, void *arg)
+{
+ int vret;
+
+ if (self->first) {
+ vret = visit(self->first, arg);
+ if (vret != 0)
+ return vret;
+ }
+ if (self->last) {
+ vret = visit(self->last, arg);
+ if (vret != 0)
+ return vret;
+ }
+
+ return 0;
+}
+
+static int
+Noddy_clear(Noddy *self)
+{
+ PyObject *tmp;
+
+ tmp = self->first;
+ self->first = NULL;
+ Py_XDECREF(tmp);
+
+ tmp = self->last;
+ self->last = NULL;
+ Py_XDECREF(tmp);
+
+ return 0;
+}
+
+static void
+Noddy_dealloc(Noddy* self)
+{
+ Noddy_clear(self);
+ self->ob_type->tp_free((PyObject*)self);
+}
+
+static PyObject *
+Noddy_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+ Noddy *self;
+
+ self = (Noddy *)type->tp_alloc(type, 0);
+ if (self != NULL) {
+ self->first = PyString_FromString("");
+ if (self->first == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->last = PyString_FromString("");
+ if (self->last == NULL)
+ {
+ Py_DECREF(self);
+ return NULL;
+ }
+
+ self->number = 0;
+ }
+
+ return (PyObject *)self;
+}
+
+static int
+Noddy_init(Noddy *self, PyObject *args, PyObject *kwds)
+{
+ PyObject *first=NULL, *last=NULL, *tmp;
+
+ static char *kwlist[] = {"first", "last", "number", NULL};
+
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
+ &first, &last,
+ &self->number))
+ return -1;
+
+ if (first) {
+ tmp = self->first;
+ Py_INCREF(first);
+ self->first = first;
+ Py_XDECREF(tmp);
+ }
+
+ if (last) {
+ tmp = self->last;
+ Py_INCREF(last);
+ self->last = last;
+ Py_XDECREF(tmp);
+ }
+
+ return 0;
+}
+
+
+static PyMemberDef Noddy_members[] = {
+ {"first", T_OBJECT_EX, offsetof(Noddy, first), 0,
+ "first name"},
+ {"last", T_OBJECT_EX, offsetof(Noddy, last), 0,
+ "last name"},
+ {"number", T_INT, offsetof(Noddy, number), 0,
+ "noddy number"},
+ {NULL} /* Sentinel */
+};
+
+static PyObject *
+Noddy_name(Noddy* self)
+{
+ static PyObject *format = NULL;
+ PyObject *args, *result;
+
+ if (format == NULL) {
+ format = PyString_FromString("%s %s");
+ if (format == NULL)
+ return NULL;
+ }
+
+ if (self->first == NULL) {
+ PyErr_SetString(PyExc_AttributeError, "first");
+ return NULL;
+ }
+
+ if (self->last == NULL) {
+ PyErr_SetString(PyExc_AttributeError, "last");
+ return NULL;
+ }
+
+ args = Py_BuildValue("OO", self->first, self->last);
+ if (args == NULL)
+ return NULL;
+
+ result = PyString_Format(format, args);
+ Py_DECREF(args);
+
+ return result;
+}
+
+static PyMethodDef Noddy_methods[] = {
+ {"name", (PyCFunction)Noddy_name, METH_NOARGS,
+ "Return the name, combining the first and last name"
+ },
+ {NULL} /* Sentinel */
+};
+
+static PyTypeObject NoddyType = {
+ PyObject_HEAD_INIT(NULL)
+ 0, /*ob_size*/
+ "noddy.Noddy", /*tp_name*/
+ sizeof(Noddy), /*tp_basicsize*/
+ 0, /*tp_itemsize*/
+ (destructor)Noddy_dealloc, /*tp_dealloc*/
+ 0, /*tp_print*/
+ 0, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+ 0, /*tp_as_number*/
+ 0, /*tp_as_sequence*/
+ 0, /*tp_as_mapping*/
+ 0, /*tp_hash */
+ 0, /*tp_call*/
+ 0, /*tp_str*/
+ 0, /*tp_getattro*/
+ 0, /*tp_setattro*/
+ 0, /*tp_as_buffer*/
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+ "Noddy objects", /* tp_doc */
+ (traverseproc)Noddy_traverse, /* tp_traverse */
+ (inquiry)Noddy_clear, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
+ Noddy_methods, /* tp_methods */
+ Noddy_members, /* tp_members */
+ 0, /* tp_getset */
+ 0, /* tp_base */
+ 0, /* tp_dict */
+ 0, /* tp_descr_get */
+ 0, /* tp_descr_set */
+ 0, /* tp_dictoffset */
+ (initproc)Noddy_init, /* tp_init */
+ 0, /* tp_alloc */
+ Noddy_new, /* tp_new */
+};
+
+static PyMethodDef module_methods[] = {
+ {NULL} /* Sentinel */
+};
+
+#ifndef PyMODINIT_FUNC /* declarations for DLL import/export */
+#define PyMODINIT_FUNC void
+#endif
+PyMODINIT_FUNC
+initnoddy4(void)
+{
+ PyObject* m;
+
+ if (PyType_Ready(&NoddyType) < 0)
+ return;
+
+ m = Py_InitModule3("noddy4", module_methods,
+ "Example module that creates an extension type.");
+
+ if (m == NULL)
+ return;
+
+ Py_INCREF(&NoddyType);
+ PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
+}
diff --git a/Doc/includes/run-func.c b/Doc/includes/run-func.c
new file mode 100644
index 0000000000..5a7df0d980
--- /dev/null
+++ b/Doc/includes/run-func.c
@@ -0,0 +1,68 @@
+#include <Python.h>
+
+int
+main(int argc, char *argv[])
+{
+ PyObject *pName, *pModule, *pDict, *pFunc;
+ PyObject *pArgs, *pValue;
+ int i;
+
+ if (argc < 3) {
+ fprintf(stderr,"Usage: call pythonfile funcname [args]\n");
+ return 1;
+ }
+
+ Py_Initialize();
+ pName = PyString_FromString(argv[1]);
+ /* Error checking of pName left out */
+
+ pModule = PyImport_Import(pName);
+ Py_DECREF(pName);
+
+ if (pModule != NULL) {
+ pFunc = PyObject_GetAttrString(pModule, argv[2]);
+ /* pFunc is a new reference */
+
+ if (pFunc && PyCallable_Check(pFunc)) {
+ pArgs = PyTuple_New(argc - 3);
+ for (i = 0; i < argc - 3; ++i) {
+ pValue = PyInt_FromLong(atoi(argv[i + 3]));
+ if (!pValue) {
+ Py_DECREF(pArgs);
+ Py_DECREF(pModule);
+ fprintf(stderr, "Cannot convert argument\n");
+ return 1;
+ }
+ /* pValue reference stolen here: */
+ PyTuple_SetItem(pArgs, i, pValue);
+ }
+ pValue = PyObject_CallObject(pFunc, pArgs);
+ Py_DECREF(pArgs);
+ if (pValue != NULL) {
+ printf("Result of call: %ld\n", PyInt_AsLong(pValue));
+ Py_DECREF(pValue);
+ }
+ else {
+ Py_DECREF(pFunc);
+ Py_DECREF(pModule);
+ PyErr_Print();
+ fprintf(stderr,"Call failed\n");
+ return 1;
+ }
+ }
+ else {
+ if (PyErr_Occurred())
+ PyErr_Print();
+ fprintf(stderr, "Cannot find function \"%s\"\n", argv[2]);
+ }
+ Py_XDECREF(pFunc);
+ Py_DECREF(pModule);
+ }
+ else {
+ PyErr_Print();
+ fprintf(stderr, "Failed to load \"%s\"\n", argv[1]);
+ return 1;
+ }
+ Py_Finalize();
+ return 0;
+}
diff --git a/Doc/includes/setup.py b/Doc/includes/setup.py
new file mode 100644
index 0000000000..b853d23b17
--- /dev/null
+++ b/Doc/includes/setup.py
@@ -0,0 +1,8 @@
+from distutils.core import setup, Extension
+setup(name="noddy", version="1.0",
+ ext_modules=[
+ Extension("noddy", ["noddy.c"]),
+ Extension("noddy2", ["noddy2.c"]),
+ Extension("noddy3", ["noddy3.c"]),
+ Extension("noddy4", ["noddy4.c"]),
+ ])
diff --git a/Doc/includes/shoddy.c b/Doc/includes/shoddy.c
new file mode 100644
index 0000000000..07a4177548
--- /dev/null
+++ b/Doc/includes/shoddy.c
@@ -0,0 +1,91 @@
+#include <Python.h>
+
+typedef struct {
+ PyListObject list;
+ int state;
+} Shoddy;
+
+
+static PyObject *
+Shoddy_increment(Shoddy *self, PyObject *unused)
+{
+ self->state++;
+ return PyInt_FromLong(self->state);
+}
+
+
+static PyMethodDef Shoddy_methods[] = {
+ {"increment", (PyCFunction)Shoddy_increment, METH_NOARGS,
+ PyDoc_STR("increment state counter")},
+ {NULL, NULL},
+};
+
+static int
+Shoddy_init(Shoddy *self, PyObject *args, PyObject *kwds)
+{
+ if (PyList_Type.tp_init((PyObject *)self, args, kwds) < 0)
+ return -1;
+ self->state = 0;
+ return 0;
+}
+
+
+static PyTypeObject ShoddyType = {
+ PyObject_HEAD_INIT(NULL)
+ 0, /* ob_size */
+ "shoddy.Shoddy", /* tp_name */
+ sizeof(Shoddy), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ 0, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT |
+ Py_TPFLAGS_BASETYPE, /* tp_flags */
+ 0, /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
+ Shoddy_methods, /* tp_methods */
+ 0, /* tp_members */
+ 0, /* tp_getset */
+ 0, /* tp_base */
+ 0, /* tp_dict */
+ 0, /* tp_descr_get */
+ 0, /* tp_descr_set */
+ 0, /* tp_dictoffset */
+ (initproc)Shoddy_init, /* tp_init */
+ 0, /* tp_alloc */
+ 0, /* tp_new */
+};
+
+PyMODINIT_FUNC
+initshoddy(void)
+{
+ PyObject *m;
+
+ ShoddyType.tp_base = &PyList_Type;
+ if (PyType_Ready(&ShoddyType) < 0)
+ return;
+
+ m = Py_InitModule3("shoddy", NULL, "Shoddy module");
+ if (m == NULL)
+ return;
+
+ Py_INCREF(&ShoddyType);
+ PyModule_AddObject(m, "Shoddy", (PyObject *) &ShoddyType);
+}
diff --git a/Doc/includes/sqlite3/adapter_datetime.py b/Doc/includes/sqlite3/adapter_datetime.py
new file mode 100644
index 0000000000..5869e22b32
--- /dev/null
+++ b/Doc/includes/sqlite3/adapter_datetime.py
@@ -0,0 +1,14 @@
+import sqlite3
+import datetime, time
+
+def adapt_datetime(ts):
+ return time.mktime(ts.timetuple())
+
+sqlite3.register_adapter(datetime.datetime, adapt_datetime)
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+
+now = datetime.datetime.now()
+cur.execute("select ?", (now,))
+print(cur.fetchone()[0])
diff --git a/Doc/includes/sqlite3/adapter_point_1.py b/Doc/includes/sqlite3/adapter_point_1.py
new file mode 100644
index 0000000000..1343acde3c
--- /dev/null
+++ b/Doc/includes/sqlite3/adapter_point_1.py
@@ -0,0 +1,16 @@
+import sqlite3
+
+class Point(object):
+ def __init__(self, x, y):
+ self.x, self.y = x, y
+
+ def __conform__(self, protocol):
+ if protocol is sqlite3.PrepareProtocol:
+ return "%f;%f" % (self.x, self.y)
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+
+p = Point(4.0, -3.2)
+cur.execute("select ?", (p,))
+print(cur.fetchone()[0])
diff --git a/Doc/includes/sqlite3/adapter_point_2.py b/Doc/includes/sqlite3/adapter_point_2.py
new file mode 100644
index 0000000000..1e1719a3cc
--- /dev/null
+++ b/Doc/includes/sqlite3/adapter_point_2.py
@@ -0,0 +1,17 @@
+import sqlite3
+
+class Point(object):
+ def __init__(self, x, y):
+ self.x, self.y = x, y
+
+def adapt_point(point):
+ return "%f;%f" % (point.x, point.y)
+
+sqlite3.register_adapter(Point, adapt_point)
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+
+p = Point(4.0, -3.2)
+cur.execute("select ?", (p,))
+print(cur.fetchone()[0])
diff --git a/Doc/includes/sqlite3/collation_reverse.py b/Doc/includes/sqlite3/collation_reverse.py
new file mode 100644
index 0000000000..bfd7f5bd9f
--- /dev/null
+++ b/Doc/includes/sqlite3/collation_reverse.py
@@ -0,0 +1,15 @@
+import sqlite3
+
+def collate_reverse(string1, string2):
+ return -cmp(string1, string2)
+
+con = sqlite3.connect(":memory:")
+con.create_collation("reverse", collate_reverse)
+
+cur = con.cursor()
+cur.execute("create table test(x)")
+cur.executemany("insert into test(x) values (?)", [("a",), ("b",)])
+cur.execute("select x from test order by x collate reverse")
+for row in cur:
+ print(row)
+con.close()
diff --git a/Doc/includes/sqlite3/complete_statement.py b/Doc/includes/sqlite3/complete_statement.py
new file mode 100644
index 0000000000..cd38d7305b
--- /dev/null
+++ b/Doc/includes/sqlite3/complete_statement.py
@@ -0,0 +1,30 @@
+# A minimal SQLite shell for experiments
+
+import sqlite3
+
+con = sqlite3.connect(":memory:")
+con.isolation_level = None
+cur = con.cursor()
+
+buffer = ""
+
+print("Enter your SQL commands to execute in sqlite3.")
+print("Enter a blank line to exit.")
+
+while True:
+ line = input()
+ if line == "":
+ break
+ buffer += line
+ if sqlite3.complete_statement(buffer):
+ try:
+ buffer = buffer.strip()
+ cur.execute(buffer)
+
+ if buffer.lstrip().upper().startswith("SELECT"):
+ print(cur.fetchall())
+ except sqlite3.Error as e:
+ print("An error occurred:", e.args[0])
+ buffer = ""
+
+con.close()
diff --git a/Doc/includes/sqlite3/connect_db_1.py b/Doc/includes/sqlite3/connect_db_1.py
new file mode 100644
index 0000000000..1b97523286
--- /dev/null
+++ b/Doc/includes/sqlite3/connect_db_1.py
@@ -0,0 +1,3 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
diff --git a/Doc/includes/sqlite3/connect_db_2.py b/Doc/includes/sqlite3/connect_db_2.py
new file mode 100644
index 0000000000..f9728b3613
--- /dev/null
+++ b/Doc/includes/sqlite3/connect_db_2.py
@@ -0,0 +1,3 @@
+import sqlite3
+
+con = sqlite3.connect(":memory:")
diff --git a/Doc/includes/sqlite3/converter_point.py b/Doc/includes/sqlite3/converter_point.py
new file mode 100644
index 0000000000..d0707abd2e
--- /dev/null
+++ b/Doc/includes/sqlite3/converter_point.py
@@ -0,0 +1,47 @@
+import sqlite3
+
+class Point(object):
+ def __init__(self, x, y):
+ self.x, self.y = x, y
+
+ def __repr__(self):
+ return "(%f;%f)" % (self.x, self.y)
+
+def adapt_point(point):
+ return "%f;%f" % (point.x, point.y)
+
+def convert_point(s):
+ x, y = list(map(float, s.split(";")))
+ return Point(x, y)
+
+# Register the adapter
+sqlite3.register_adapter(Point, adapt_point)
+
+# Register the converter
+sqlite3.register_converter("point", convert_point)
+
+p = Point(4.0, -3.2)
+
+#########################
+# 1) Using declared types
+con = sqlite3.connect(":memory:", detect_types=sqlite3.PARSE_DECLTYPES)
+cur = con.cursor()
+cur.execute("create table test(p point)")
+
+cur.execute("insert into test(p) values (?)", (p,))
+cur.execute("select p from test")
+print("with declared types:", cur.fetchone()[0])
+cur.close()
+con.close()
+
+#######################
+# 1) Using column names
+con = sqlite3.connect(":memory:", detect_types=sqlite3.PARSE_COLNAMES)
+cur = con.cursor()
+cur.execute("create table test(p)")
+
+cur.execute("insert into test(p) values (?)", (p,))
+cur.execute('select p as "p [point]" from test')
+print("with column names:", cur.fetchone()[0])
+cur.close()
+con.close()
diff --git a/Doc/includes/sqlite3/countcursors.py b/Doc/includes/sqlite3/countcursors.py
new file mode 100644
index 0000000000..ef3e70a2a9
--- /dev/null
+++ b/Doc/includes/sqlite3/countcursors.py
@@ -0,0 +1,15 @@
+import sqlite3
+
+class CountCursorsConnection(sqlite3.Connection):
+ def __init__(self, *args, **kwargs):
+ sqlite3.Connection.__init__(self, *args, **kwargs)
+ self.numcursors = 0
+
+ def cursor(self, *args, **kwargs):
+ self.numcursors += 1
+ return sqlite3.Connection.cursor(self, *args, **kwargs)
+
+con = sqlite3.connect(":memory:", factory=CountCursorsConnection)
+cur1 = con.cursor()
+cur2 = con.cursor()
+print(con.numcursors)
diff --git a/Doc/includes/sqlite3/createdb.py b/Doc/includes/sqlite3/createdb.py
new file mode 100644
index 0000000000..ee2950bdf8
--- /dev/null
+++ b/Doc/includes/sqlite3/createdb.py
@@ -0,0 +1,28 @@
+# Not referenced from the documentation, but builds the database file the other
+# code snippets expect.
+
+import sqlite3
+import os
+
+DB_FILE = "mydb"
+
+if os.path.exists(DB_FILE):
+ os.remove(DB_FILE)
+
+con = sqlite3.connect(DB_FILE)
+cur = con.cursor()
+cur.execute("""
+ create table people
+ (
+ name_last varchar(20),
+ age integer
+ )
+ """)
+
+cur.execute("insert into people (name_last, age) values ('Yeltsin', 72)")
+cur.execute("insert into people (name_last, age) values ('Putin', 51)")
+
+con.commit()
+
+cur.close()
+con.close()
diff --git a/Doc/includes/sqlite3/execsql_fetchonerow.py b/Doc/includes/sqlite3/execsql_fetchonerow.py
new file mode 100644
index 0000000000..078873bfc9
--- /dev/null
+++ b/Doc/includes/sqlite3/execsql_fetchonerow.py
@@ -0,0 +1,17 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
+
+cur = con.cursor()
+SELECT = "select name_last, age from people order by age, name_last"
+
+# 1. Iterate over the rows available from the cursor, unpacking the
+# resulting sequences to yield their elements (name_last, age):
+cur.execute(SELECT)
+for (name_last, age) in cur:
+ print('%s is %d years old.' % (name_last, age))
+
+# 2. Equivalently:
+cur.execute(SELECT)
+for row in cur:
+ print('%s is %d years old.' % (row[0], row[1]))
diff --git a/Doc/includes/sqlite3/execsql_printall_1.py b/Doc/includes/sqlite3/execsql_printall_1.py
new file mode 100644
index 0000000000..a4ce5c5281
--- /dev/null
+++ b/Doc/includes/sqlite3/execsql_printall_1.py
@@ -0,0 +1,13 @@
+import sqlite3
+
+# Create a connection to the database file "mydb":
+con = sqlite3.connect("mydb")
+
+# Get a Cursor object that operates in the context of Connection con:
+cur = con.cursor()
+
+# Execute the SELECT statement:
+cur.execute("select * from people order by age")
+
+# Retrieve all rows as a sequence and print that sequence:
+print(cur.fetchall())
diff --git a/Doc/includes/sqlite3/execute_1.py b/Doc/includes/sqlite3/execute_1.py
new file mode 100644
index 0000000000..3d08840b86
--- /dev/null
+++ b/Doc/includes/sqlite3/execute_1.py
@@ -0,0 +1,11 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
+
+cur = con.cursor()
+
+who = "Yeltsin"
+age = 72
+
+cur.execute("select name_last, age from people where name_last=? and age=?", (who, age))
+print(cur.fetchone())
diff --git a/Doc/includes/sqlite3/execute_2.py b/Doc/includes/sqlite3/execute_2.py
new file mode 100644
index 0000000000..84734f967f
--- /dev/null
+++ b/Doc/includes/sqlite3/execute_2.py
@@ -0,0 +1,12 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
+
+cur = con.cursor()
+
+who = "Yeltsin"
+age = 72
+
+cur.execute("select name_last, age from people where name_last=:who and age=:age",
+ {"who": who, "age": age})
+print(cur.fetchone())
diff --git a/Doc/includes/sqlite3/execute_3.py b/Doc/includes/sqlite3/execute_3.py
new file mode 100644
index 0000000000..0353683fc7
--- /dev/null
+++ b/Doc/includes/sqlite3/execute_3.py
@@ -0,0 +1,12 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
+
+cur = con.cursor()
+
+who = "Yeltsin"
+age = 72
+
+cur.execute("select name_last, age from people where name_last=:who and age=:age",
+ locals())
+print(cur.fetchone())
diff --git a/Doc/includes/sqlite3/executemany_1.py b/Doc/includes/sqlite3/executemany_1.py
new file mode 100644
index 0000000000..efae10637c
--- /dev/null
+++ b/Doc/includes/sqlite3/executemany_1.py
@@ -0,0 +1,24 @@
+import sqlite3
+
+class IterChars:
+ def __init__(self):
+ self.count = ord('a')
+
+ def __iter__(self):
+ return self
+
+ def __next__(self):
+ if self.count > ord('z'):
+ raise StopIteration
+ self.count += 1
+ return (chr(self.count - 1),) # this is a 1-tuple
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+cur.execute("create table characters(c)")
+
+theIter = IterChars()
+cur.executemany("insert into characters(c) values (?)", theIter)
+
+cur.execute("select c from characters")
+print(cur.fetchall())
diff --git a/Doc/includes/sqlite3/executemany_2.py b/Doc/includes/sqlite3/executemany_2.py
new file mode 100644
index 0000000000..518cd9430d
--- /dev/null
+++ b/Doc/includes/sqlite3/executemany_2.py
@@ -0,0 +1,15 @@
+import sqlite3
+
+def char_generator():
+ import string
+ for c in string.letters[:26]:
+ yield (c,)
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+cur.execute("create table characters(c)")
+
+cur.executemany("insert into characters(c) values (?)", char_generator())
+
+cur.execute("select c from characters")
+print(cur.fetchall())
diff --git a/Doc/includes/sqlite3/executescript.py b/Doc/includes/sqlite3/executescript.py
new file mode 100644
index 0000000000..7e5358178d
--- /dev/null
+++ b/Doc/includes/sqlite3/executescript.py
@@ -0,0 +1,24 @@
+import sqlite3
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+cur.executescript("""
+ create table person(
+ firstname,
+ lastname,
+ age
+ );
+
+ create table book(
+ title,
+ author,
+ published
+ );
+
+ insert into book(title, author, published)
+ values (
+ 'Dirk Gently''s Holistic Detective Agency',
+ 'Douglas Adams',
+ 1987
+ );
+ """)
diff --git a/Doc/includes/sqlite3/insert_more_people.py b/Doc/includes/sqlite3/insert_more_people.py
new file mode 100644
index 0000000000..edbc79e7e5
--- /dev/null
+++ b/Doc/includes/sqlite3/insert_more_people.py
@@ -0,0 +1,16 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
+
+cur = con.cursor()
+
+newPeople = (
+ ('Lebed' , 53),
+ ('Zhirinovsky' , 57),
+ )
+
+for person in newPeople:
+ cur.execute("insert into people (name_last, age) values (?, ?)", person)
+
+# The changes will not be saved unless the transaction is committed explicitly:
+con.commit()
diff --git a/Doc/includes/sqlite3/md5func.py b/Doc/includes/sqlite3/md5func.py
new file mode 100644
index 0000000000..b7bc05b379
--- /dev/null
+++ b/Doc/includes/sqlite3/md5func.py
@@ -0,0 +1,11 @@
+import sqlite3
+import hashlib
+
+def md5sum(t):
+ return hashlib.md5(t).hexdigest()
+
+con = sqlite3.connect(":memory:")
+con.create_function("md5", 1, md5sum)
+cur = con.cursor()
+cur.execute("select md5(?)", ("foo",))
+print(cur.fetchone()[0])
diff --git a/Doc/includes/sqlite3/mysumaggr.py b/Doc/includes/sqlite3/mysumaggr.py
new file mode 100644
index 0000000000..d2dfd2c0b9
--- /dev/null
+++ b/Doc/includes/sqlite3/mysumaggr.py
@@ -0,0 +1,20 @@
+import sqlite3
+
+class MySum:
+ def __init__(self):
+ self.count = 0
+
+ def step(self, value):
+ self.count += value
+
+ def finalize(self):
+ return self.count
+
+con = sqlite3.connect(":memory:")
+con.create_aggregate("mysum", 1, MySum)
+cur = con.cursor()
+cur.execute("create table test(i)")
+cur.execute("insert into test(i) values (1)")
+cur.execute("insert into test(i) values (2)")
+cur.execute("select mysum(i) from test")
+print(cur.fetchone()[0])
diff --git a/Doc/includes/sqlite3/parse_colnames.py b/Doc/includes/sqlite3/parse_colnames.py
new file mode 100644
index 0000000000..cc68c76459
--- /dev/null
+++ b/Doc/includes/sqlite3/parse_colnames.py
@@ -0,0 +1,8 @@
+import sqlite3
+import datetime
+
+con = sqlite3.connect(":memory:", detect_types=sqlite3.PARSE_COLNAMES)
+cur = con.cursor()
+cur.execute('select ? as "x [timestamp]"', (datetime.datetime.now(),))
+dt = cur.fetchone()[0]
+print(dt, type(dt))
diff --git a/Doc/includes/sqlite3/pysqlite_datetime.py b/Doc/includes/sqlite3/pysqlite_datetime.py
new file mode 100644
index 0000000000..68d49358a5
--- /dev/null
+++ b/Doc/includes/sqlite3/pysqlite_datetime.py
@@ -0,0 +1,20 @@
+import sqlite3
+import datetime
+
+con = sqlite3.connect(":memory:", detect_types=sqlite3.PARSE_DECLTYPES|sqlite3.PARSE_COLNAMES)
+cur = con.cursor()
+cur.execute("create table test(d date, ts timestamp)")
+
+today = datetime.date.today()
+now = datetime.datetime.now()
+
+cur.execute("insert into test(d, ts) values (?, ?)", (today, now))
+cur.execute("select d, ts from test")
+row = cur.fetchone()
+print(today, "=>", row[0], type(row[0]))
+print(now, "=>", row[1], type(row[1]))
+
+cur.execute('select current_date as "d [date]", current_timestamp as "ts [timestamp]"')
+row = cur.fetchone()
+print("current_date", row[0], type(row[0]))
+print("current_timestamp", row[1], type(row[1]))
diff --git a/Doc/includes/sqlite3/row_factory.py b/Doc/includes/sqlite3/row_factory.py
new file mode 100644
index 0000000000..e436ffc6c8
--- /dev/null
+++ b/Doc/includes/sqlite3/row_factory.py
@@ -0,0 +1,13 @@
+import sqlite3
+
+def dict_factory(cursor, row):
+ d = {}
+ for idx, col in enumerate(cursor.description):
+ d[col[0]] = row[idx]
+ return d
+
+con = sqlite3.connect(":memory:")
+con.row_factory = dict_factory
+cur = con.cursor()
+cur.execute("select 1 as a")
+print(cur.fetchone()["a"])
diff --git a/Doc/includes/sqlite3/rowclass.py b/Doc/includes/sqlite3/rowclass.py
new file mode 100644
index 0000000000..3fa0b87389
--- /dev/null
+++ b/Doc/includes/sqlite3/rowclass.py
@@ -0,0 +1,12 @@
+import sqlite3
+
+con = sqlite3.connect("mydb")
+con.row_factory = sqlite3.Row
+
+cur = con.cursor()
+cur.execute("select name_last, age from people")
+for row in cur:
+ assert row[0] == row["name_last"]
+ assert row["name_last"] == row["nAmE_lAsT"]
+ assert row[1] == row["age"]
+ assert row[1] == row["AgE"]
diff --git a/Doc/includes/sqlite3/shared_cache.py b/Doc/includes/sqlite3/shared_cache.py
new file mode 100644
index 0000000000..bf1d7b4a21
--- /dev/null
+++ b/Doc/includes/sqlite3/shared_cache.py
@@ -0,0 +1,6 @@
+import sqlite3
+
+# The shared cache is only available in SQLite versions 3.3.3 or later
+# See the SQLite documentaton for details.
+
+sqlite3.enable_shared_cache(True)
diff --git a/Doc/includes/sqlite3/shortcut_methods.py b/Doc/includes/sqlite3/shortcut_methods.py
new file mode 100644
index 0000000000..596d87c18e
--- /dev/null
+++ b/Doc/includes/sqlite3/shortcut_methods.py
@@ -0,0 +1,21 @@
+import sqlite3
+
+persons = [
+ ("Hugo", "Boss"),
+ ("Calvin", "Klein")
+ ]
+
+con = sqlite3.connect(":memory:")
+
+# Create the table
+con.execute("create table person(firstname, lastname)")
+
+# Fill the table
+con.executemany("insert into person(firstname, lastname) values (?, ?)", persons)
+
+# Print the table contents
+for row in con.execute("select firstname, lastname from person"):
+ print(row)
+
+# Using a dummy WHERE clause to not let SQLite take the shortcut table deletes.
+print("I just deleted", con.execute("delete from person where 1=1").rowcount, "rows")
diff --git a/Doc/includes/sqlite3/simple_tableprinter.py b/Doc/includes/sqlite3/simple_tableprinter.py
new file mode 100644
index 0000000000..231d8726cd
--- /dev/null
+++ b/Doc/includes/sqlite3/simple_tableprinter.py
@@ -0,0 +1,26 @@
+import sqlite3
+
+FIELD_MAX_WIDTH = 20
+TABLE_NAME = 'people'
+SELECT = 'select * from %s order by age, name_last' % TABLE_NAME
+
+con = sqlite3.connect("mydb")
+
+cur = con.cursor()
+cur.execute(SELECT)
+
+# Print a header.
+for fieldDesc in cur.description:
+ print(fieldDesc[0].ljust(FIELD_MAX_WIDTH), end=' ')
+print() # Finish the header with a newline.
+print('-' * 78)
+
+# For each row, print the value of each field left-justified within
+# the maximum possible width of that field.
+fieldIndices = range(len(cur.description))
+for row in cur:
+ for fieldIndex in fieldIndices:
+ fieldValue = str(row[fieldIndex])
+ print(fieldValue.ljust(FIELD_MAX_WIDTH), end=' ')
+
+ print() # Finish the row with a newline.
diff --git a/Doc/includes/sqlite3/text_factory.py b/Doc/includes/sqlite3/text_factory.py
new file mode 100644
index 0000000000..2dab8e453f
--- /dev/null
+++ b/Doc/includes/sqlite3/text_factory.py
@@ -0,0 +1,42 @@
+import sqlite3
+
+con = sqlite3.connect(":memory:")
+cur = con.cursor()
+
+# Create the table
+con.execute("create table person(lastname, firstname)")
+
+AUSTRIA = "\xd6sterreich"
+
+# by default, rows are returned as Unicode
+cur.execute("select ?", (AUSTRIA,))
+row = cur.fetchone()
+assert row[0] == AUSTRIA
+
+# but we can make pysqlite always return bytestrings ...
+con.text_factory = str
+cur.execute("select ?", (AUSTRIA,))
+row = cur.fetchone()
+assert type(row[0]) == str
+# the bytestrings will be encoded in UTF-8, unless you stored garbage in the
+# database ...
+assert row[0] == AUSTRIA.encode("utf-8")
+
+# we can also implement a custom text_factory ...
+# here we implement one that will ignore Unicode characters that cannot be
+# decoded from UTF-8
+con.text_factory = lambda x: str(x, "utf-8", "ignore")
+cur.execute("select ?", ("this is latin1 and would normally create errors" + "\xe4\xf6\xfc".encode("latin1"),))
+row = cur.fetchone()
+assert type(row[0]) == str
+
+# pysqlite offers a builtin optimized text_factory that will return bytestring
+# objects, if the data is in ASCII only, and otherwise return unicode objects
+con.text_factory = sqlite3.OptimizedUnicode
+cur.execute("select ?", (AUSTRIA,))
+row = cur.fetchone()
+assert type(row[0]) == str
+
+cur.execute("select ?", ("Germany",))
+row = cur.fetchone()
+assert type(row[0]) == str
diff --git a/Doc/includes/test.py b/Doc/includes/test.py
new file mode 100644
index 0000000000..7ebf46afd1
--- /dev/null
+++ b/Doc/includes/test.py
@@ -0,0 +1,213 @@
+"""Test module for the noddy examples
+
+Noddy 1:
+
+>>> import noddy
+>>> n1 = noddy.Noddy()
+>>> n2 = noddy.Noddy()
+>>> del n1
+>>> del n2
+
+
+Noddy 2
+
+>>> import noddy2
+>>> n1 = noddy2.Noddy('jim', 'fulton', 42)
+>>> n1.first
+'jim'
+>>> n1.last
+'fulton'
+>>> n1.number
+42
+>>> n1.name()
+'jim fulton'
+>>> n1.first = 'will'
+>>> n1.name()
+'will fulton'
+>>> n1.last = 'tell'
+>>> n1.name()
+'will tell'
+>>> del n1.first
+>>> n1.name()
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n1.first
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n1.first = 'drew'
+>>> n1.first
+'drew'
+>>> del n1.number
+Traceback (most recent call last):
+...
+TypeError: can't delete numeric/char attribute
+>>> n1.number=2
+>>> n1.number
+2
+>>> n1.first = 42
+>>> n1.name()
+'42 tell'
+>>> n2 = noddy2.Noddy()
+>>> n2.name()
+' '
+>>> n2.first
+''
+>>> n2.last
+''
+>>> del n2.first
+>>> n2.first
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n2.first
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n2.name()
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+AttributeError: first
+>>> n2.number
+0
+>>> n3 = noddy2.Noddy('jim', 'fulton', 'waaa')
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+TypeError: an integer is required
+>>> del n1
+>>> del n2
+
+
+Noddy 3
+
+>>> import noddy3
+>>> n1 = noddy3.Noddy('jim', 'fulton', 42)
+>>> n1 = noddy3.Noddy('jim', 'fulton', 42)
+>>> n1.name()
+'jim fulton'
+>>> del n1.first
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+TypeError: Cannot delete the first attribute
+>>> n1.first = 42
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+TypeError: The first attribute value must be a string
+>>> n1.first = 'will'
+>>> n1.name()
+'will fulton'
+>>> n2 = noddy3.Noddy()
+>>> n2 = noddy3.Noddy()
+>>> n2 = noddy3.Noddy()
+>>> n3 = noddy3.Noddy('jim', 'fulton', 'waaa')
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+TypeError: an integer is required
+>>> del n1
+>>> del n2
+
+Noddy 4
+
+>>> import noddy4
+>>> n1 = noddy4.Noddy('jim', 'fulton', 42)
+>>> n1.first
+'jim'
+>>> n1.last
+'fulton'
+>>> n1.number
+42
+>>> n1.name()
+'jim fulton'
+>>> n1.first = 'will'
+>>> n1.name()
+'will fulton'
+>>> n1.last = 'tell'
+>>> n1.name()
+'will tell'
+>>> del n1.first
+>>> n1.name()
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n1.first
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n1.first = 'drew'
+>>> n1.first
+'drew'
+>>> del n1.number
+Traceback (most recent call last):
+...
+TypeError: can't delete numeric/char attribute
+>>> n1.number=2
+>>> n1.number
+2
+>>> n1.first = 42
+>>> n1.name()
+'42 tell'
+>>> n2 = noddy4.Noddy()
+>>> n2 = noddy4.Noddy()
+>>> n2 = noddy4.Noddy()
+>>> n2 = noddy4.Noddy()
+>>> n2.name()
+' '
+>>> n2.first
+''
+>>> n2.last
+''
+>>> del n2.first
+>>> n2.first
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n2.first
+Traceback (most recent call last):
+...
+AttributeError: first
+>>> n2.name()
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+AttributeError: first
+>>> n2.number
+0
+>>> n3 = noddy4.Noddy('jim', 'fulton', 'waaa')
+Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+TypeError: an integer is required
+
+
+Test cyclic gc(?)
+
+>>> import gc
+>>> gc.disable()
+
+>>> x = []
+>>> l = [x]
+>>> n2.first = l
+>>> n2.first
+[[]]
+>>> l.append(n2)
+>>> del l
+>>> del n1
+>>> del n2
+>>> sys.getrefcount(x)
+3
+>>> ignore = gc.collect()
+>>> sys.getrefcount(x)
+2
+
+>>> gc.enable()
+"""
+
+import os
+import sys
+from distutils.util import get_platform
+PLAT_SPEC = "%s-%s" % (get_platform(), sys.version[0:3])
+src = os.path.join("build", "lib.%s" % PLAT_SPEC)
+sys.path.append(src)
+
+if __name__ == "__main__":
+ import doctest, __main__
+ doctest.testmod(__main__)
diff --git a/Doc/includes/typestruct.h b/Doc/includes/typestruct.h
new file mode 100644
index 0000000000..0afe375d4f
--- /dev/null
+++ b/Doc/includes/typestruct.h
@@ -0,0 +1,76 @@
+typedef struct _typeobject {
+ PyObject_VAR_HEAD
+ char *tp_name; /* For printing, in format "<module>.<name>" */
+ int tp_basicsize, tp_itemsize; /* For allocation */
+
+ /* Methods to implement standard operations */
+
+ destructor tp_dealloc;
+ printfunc tp_print;
+ getattrfunc tp_getattr;
+ setattrfunc tp_setattr;
+ cmpfunc tp_compare;
+ reprfunc tp_repr;
+
+ /* Method suites for standard classes */
+
+ PyNumberMethods *tp_as_number;
+ PySequenceMethods *tp_as_sequence;
+ PyMappingMethods *tp_as_mapping;
+
+ /* More standard operations (here for binary compatibility) */
+
+ hashfunc tp_hash;
+ ternaryfunc tp_call;
+ reprfunc tp_str;
+ getattrofunc tp_getattro;
+ setattrofunc tp_setattro;
+
+ /* Functions to access object as input/output buffer */
+ PyBufferProcs *tp_as_buffer;
+
+ /* Flags to define presence of optional/expanded features */
+ long tp_flags;
+
+ char *tp_doc; /* Documentation string */
+
+ /* Assigned meaning in release 2.0 */
+ /* call function for all accessible objects */
+ traverseproc tp_traverse;
+
+ /* delete references to contained objects */
+ inquiry tp_clear;
+
+ /* Assigned meaning in release 2.1 */
+ /* rich comparisons */
+ richcmpfunc tp_richcompare;
+
+ /* weak reference enabler */
+ long tp_weaklistoffset;
+
+ /* Added in release 2.2 */
+ /* Iterators */
+ getiterfunc tp_iter;
+ iternextfunc tp_iternext;
+
+ /* Attribute descriptor and subclassing stuff */
+ struct PyMethodDef *tp_methods;
+ struct PyMemberDef *tp_members;
+ struct PyGetSetDef *tp_getset;
+ struct _typeobject *tp_base;
+ PyObject *tp_dict;
+ descrgetfunc tp_descr_get;
+ descrsetfunc tp_descr_set;
+ long tp_dictoffset;
+ initproc tp_init;
+ allocfunc tp_alloc;
+ newfunc tp_new;
+ freefunc tp_free; /* Low-level free-memory routine */
+ inquiry tp_is_gc; /* For PyObject_IS_GC */
+ PyObject *tp_bases;
+ PyObject *tp_mro; /* method resolution order */
+ PyObject *tp_cache;
+ PyObject *tp_subclasses;
+ PyObject *tp_weaklist;
+
+} PyTypeObject;
diff --git a/Doc/includes/tzinfo-examples.py b/Doc/includes/tzinfo-examples.py
new file mode 100644
index 0000000000..5a2b8ad1a7
--- /dev/null
+++ b/Doc/includes/tzinfo-examples.py
@@ -0,0 +1,139 @@
+from datetime import tzinfo, timedelta, datetime
+
+ZERO = timedelta(0)
+HOUR = timedelta(hours=1)
+
+# A UTC class.
+
+class UTC(tzinfo):
+ """UTC"""
+
+ def utcoffset(self, dt):
+ return ZERO
+
+ def tzname(self, dt):
+ return "UTC"
+
+ def dst(self, dt):
+ return ZERO
+
+utc = UTC()
+
+# A class building tzinfo objects for fixed-offset time zones.
+# Note that FixedOffset(0, "UTC") is a different way to build a
+# UTC tzinfo object.
+
+class FixedOffset(tzinfo):
+ """Fixed offset in minutes east from UTC."""
+
+ def __init__(self, offset, name):
+ self.__offset = timedelta(minutes = offset)
+ self.__name = name
+
+ def utcoffset(self, dt):
+ return self.__offset
+
+ def tzname(self, dt):
+ return self.__name
+
+ def dst(self, dt):
+ return ZERO
+
+# A class capturing the platform's idea of local time.
+
+import time as _time
+
+STDOFFSET = timedelta(seconds = -_time.timezone)
+if _time.daylight:
+ DSTOFFSET = timedelta(seconds = -_time.altzone)
+else:
+ DSTOFFSET = STDOFFSET
+
+DSTDIFF = DSTOFFSET - STDOFFSET
+
+class LocalTimezone(tzinfo):
+
+ def utcoffset(self, dt):
+ if self._isdst(dt):
+ return DSTOFFSET
+ else:
+ return STDOFFSET
+
+ def dst(self, dt):
+ if self._isdst(dt):
+ return DSTDIFF
+ else:
+ return ZERO
+
+ def tzname(self, dt):
+ return _time.tzname[self._isdst(dt)]
+
+ def _isdst(self, dt):
+ tt = (dt.year, dt.month, dt.day,
+ dt.hour, dt.minute, dt.second,
+ dt.weekday(), 0, -1)
+ stamp = _time.mktime(tt)
+ tt = _time.localtime(stamp)
+ return tt.tm_isdst > 0
+
+Local = LocalTimezone()
+
+
+# A complete implementation of current DST rules for major US time zones.
+
+def first_sunday_on_or_after(dt):
+ days_to_go = 6 - dt.weekday()
+ if days_to_go:
+ dt += timedelta(days_to_go)
+ return dt
+
+# In the US, DST starts at 2am (standard time) on the first Sunday in April.
+DSTSTART = datetime(1, 4, 1, 2)
+# and ends at 2am (DST time; 1am standard time) on the last Sunday of Oct.
+# which is the first Sunday on or after Oct 25.
+DSTEND = datetime(1, 10, 25, 1)
+
+class USTimeZone(tzinfo):
+
+ def __init__(self, hours, reprname, stdname, dstname):
+ self.stdoffset = timedelta(hours=hours)
+ self.reprname = reprname
+ self.stdname = stdname
+ self.dstname = dstname
+
+ def __repr__(self):
+ return self.reprname
+
+ def tzname(self, dt):
+ if self.dst(dt):
+ return self.dstname
+ else:
+ return self.stdname
+
+ def utcoffset(self, dt):
+ return self.stdoffset + self.dst(dt)
+
+ def dst(self, dt):
+ if dt is None or dt.tzinfo is None:
+ # An exception may be sensible here, in one or both cases.
+ # It depends on how you want to treat them. The default
+ # fromutc() implementation (called by the default astimezone()
+ # implementation) passes a datetime with dt.tzinfo is self.
+ return ZERO
+ assert dt.tzinfo is self
+
+ # Find first Sunday in April & the last in October.
+ start = first_sunday_on_or_after(DSTSTART.replace(year=dt.year))
+ end = first_sunday_on_or_after(DSTEND.replace(year=dt.year))
+
+ # Can't compare naive to aware objects, so strip the timezone from
+ # dt first.
+ if start <= dt.replace(tzinfo=None) < end:
+ return HOUR
+ else:
+ return ZERO
+
+Eastern = USTimeZone(-5, "Eastern", "EST", "EDT")
+Central = USTimeZone(-6, "Central", "CST", "CDT")
+Mountain = USTimeZone(-7, "Mountain", "MST", "MDT")
+Pacific = USTimeZone(-8, "Pacific", "PST", "PDT")
diff --git a/Doc/install/index.rst b/Doc/install/index.rst
new file mode 100644
index 0000000000..01f17f8fad
--- /dev/null
+++ b/Doc/install/index.rst
@@ -0,0 +1,1011 @@
+.. highlightlang:: none
+
+.. _install-index:
+
+*****************************
+ Installing Python Modules
+*****************************
+
+:Author: Greg Ward
+:Release: |version|
+:Date: |today|
+
+.. % TODO:
+.. % Fill in XXX comments
+
+.. % The audience for this document includes people who don't know anything
+.. % about Python and aren't about to learn the language just in order to
+.. % install and maintain it for their users, i.e. system administrators.
+.. % Thus, I have to be sure to explain the basics at some point:
+.. % sys.path and PYTHONPATH at least. Should probably give pointers to
+.. % other docs on "import site", PYTHONSTARTUP, PYTHONHOME, etc.
+.. %
+.. % Finally, it might be useful to include all the material from my "Care
+.. % and Feeding of a Python Installation" talk in here somewhere. Yow!
+
+.. topic:: Abstract
+
+ This document describes the Python Distribution Utilities ("Distutils") from the
+ end-user's point-of-view, describing how to extend the capabilities of a
+ standard Python installation by building and installing third-party Python
+ modules and extensions.
+
+
+.. _inst-intro:
+
+Introduction
+============
+
+Although Python's extensive standard library covers many programming needs,
+there often comes a time when you need to add some new functionality to your
+Python installation in the form of third-party modules. This might be necessary
+to support your own programming, or to support an application that you want to
+use and that happens to be written in Python.
+
+In the past, there has been little support for adding third-party modules to an
+existing Python installation. With the introduction of the Python Distribution
+Utilities (Distutils for short) in Python 2.0, this changed.
+
+This document is aimed primarily at the people who need to install third-party
+Python modules: end-users and system administrators who just need to get some
+Python application running, and existing Python programmers who want to add some
+new goodies to their toolbox. You don't need to know Python to read this
+document; there will be some brief forays into using Python's interactive mode
+to explore your installation, but that's it. If you're looking for information
+on how to distribute your own Python modules so that others may use them, see
+the :ref:`distutils-index` manual.
+
+
+.. _inst-trivial-install:
+
+Best case: trivial installation
+-------------------------------
+
+In the best case, someone will have prepared a special version of the module
+distribution you want to install that is targeted specifically at your platform
+and is installed just like any other software on your platform. For example,
+the module developer might make an executable installer available for Windows
+users, an RPM package for users of RPM-based Linux systems (Red Hat, SuSE,
+Mandrake, and many others), a Debian package for users of Debian-based Linux
+systems, and so forth.
+
+In that case, you would download the installer appropriate to your platform and
+do the obvious thing with it: run it if it's an executable installer, ``rpm
+--install`` it if it's an RPM, etc. You don't need to run Python or a setup
+script, you don't need to compile anything---you might not even need to read any
+instructions (although it's always a good idea to do so anyways).
+
+Of course, things will not always be that easy. You might be interested in a
+module distribution that doesn't have an easy-to-use installer for your
+platform. In that case, you'll have to start with the source distribution
+released by the module's author/maintainer. Installing from a source
+distribution is not too hard, as long as the modules are packaged in the
+standard way. The bulk of this document is about building and installing
+modules from standard source distributions.
+
+
+.. _inst-new-standard:
+
+The new standard: Distutils
+---------------------------
+
+If you download a module source distribution, you can tell pretty quickly if it
+was packaged and distributed in the standard way, i.e. using the Distutils.
+First, the distribution's name and version number will be featured prominently
+in the name of the downloaded archive, e.g. :file:`foo-1.0.tar.gz` or
+:file:`widget-0.9.7.zip`. Next, the archive will unpack into a similarly-named
+directory: :file:`foo-1.0` or :file:`widget-0.9.7`. Additionally, the
+distribution will contain a setup script :file:`setup.py`, and a file named
+:file:`README.txt` or possibly just :file:`README`, which should explain that
+building and installing the module distribution is a simple matter of running ::
+
+ python setup.py install
+
+If all these things are true, then you already know how to build and install the
+modules you've just downloaded: Run the command above. Unless you need to
+install things in a non-standard way or customize the build process, you don't
+really need this manual. Or rather, the above command is everything you need to
+get out of this manual.
+
+
+.. _inst-standard-install:
+
+Standard Build and Install
+==========================
+
+As described in section :ref:`inst-new-standard`, building and installing a module
+distribution using the Distutils is usually one simple command::
+
+ python setup.py install
+
+On Unix, you'd run this command from a shell prompt; on Windows, you have to
+open a command prompt window ("DOS box") and do it there; on Mac OS X, you open
+a :command:`Terminal` window to get a shell prompt.
+
+
+.. _inst-platform-variations:
+
+Platform variations
+-------------------
+
+You should always run the setup command from the distribution root directory,
+i.e. the top-level subdirectory that the module source distribution unpacks
+into. For example, if you've just downloaded a module source distribution
+:file:`foo-1.0.tar.gz` onto a Unix system, the normal thing to do is::
+
+ gunzip -c foo-1.0.tar.gz | tar xf - # unpacks into directory foo-1.0
+ cd foo-1.0
+ python setup.py install
+
+On Windows, you'd probably download :file:`foo-1.0.zip`. If you downloaded the
+archive file to :file:`C:\\Temp`, then it would unpack into
+:file:`C:\\Temp\\foo-1.0`; you can use either a archive manipulator with a
+graphical user interface (such as WinZip) or a command-line tool (such as
+:program:`unzip` or :program:`pkunzip`) to unpack the archive. Then, open a
+command prompt window ("DOS box"), and run::
+
+ cd c:\Temp\foo-1.0
+ python setup.py install
+
+
+.. _inst-splitting-up:
+
+Splitting the job up
+--------------------
+
+Running ``setup.py install`` builds and installs all modules in one run. If you
+prefer to work incrementally---especially useful if you want to customize the
+build process, or if things are going wrong---you can use the setup script to do
+one thing at a time. This is particularly helpful when the build and install
+will be done by different users---for example, you might want to build a module
+distribution and hand it off to a system administrator for installation (or do
+it yourself, with super-user privileges).
+
+For example, you can build everything in one step, and then install everything
+in a second step, by invoking the setup script twice::
+
+ python setup.py build
+ python setup.py install
+
+If you do this, you will notice that running the :command:`install` command
+first runs the :command:`build` command, which---in this case---quickly notices
+that it has nothing to do, since everything in the :file:`build` directory is
+up-to-date.
+
+You may not need this ability to break things down often if all you do is
+install modules downloaded off the 'net, but it's very handy for more advanced
+tasks. If you get into distributing your own Python modules and extensions,
+you'll run lots of individual Distutils commands on their own.
+
+
+.. _inst-how-build-works:
+
+How building works
+------------------
+
+As implied above, the :command:`build` command is responsible for putting the
+files to install into a *build directory*. By default, this is :file:`build`
+under the distribution root; if you're excessively concerned with speed, or want
+to keep the source tree pristine, you can change the build directory with the
+:option:`--build-base` option. For example::
+
+ python setup.py build --build-base=/tmp/pybuild/foo-1.0
+
+(Or you could do this permanently with a directive in your system or personal
+Distutils configuration file; see section :ref:`inst-config-files`.) Normally, this
+isn't necessary.
+
+The default layout for the build tree is as follows::
+
+ --- build/ --- lib/
+ or
+ --- build/ --- lib.<plat>/
+ temp.<plat>/
+
+where ``<plat>`` expands to a brief description of the current OS/hardware
+platform and Python version. The first form, with just a :file:`lib` directory,
+is used for "pure module distributions"---that is, module distributions that
+include only pure Python modules. If a module distribution contains any
+extensions (modules written in C/C++), then the second form, with two ``<plat>``
+directories, is used. In that case, the :file:`temp.{plat}` directory holds
+temporary files generated by the compile/link process that don't actually get
+installed. In either case, the :file:`lib` (or :file:`lib.{plat}`) directory
+contains all Python modules (pure Python and extensions) that will be installed.
+
+In the future, more directories will be added to handle Python scripts,
+documentation, binary executables, and whatever else is needed to handle the job
+of installing Python modules and applications.
+
+
+.. _inst-how-install-works:
+
+How installation works
+----------------------
+
+After the :command:`build` command runs (whether you run it explicitly, or the
+:command:`install` command does it for you), the work of the :command:`install`
+command is relatively simple: all it has to do is copy everything under
+:file:`build/lib` (or :file:`build/lib.{plat}`) to your chosen installation
+directory.
+
+If you don't choose an installation directory---i.e., if you just run ``setup.py
+install``\ ---then the :command:`install` command installs to the standard
+location for third-party Python modules. This location varies by platform and
+by how you built/installed Python itself. On Unix (and Mac OS X, which is also
+Unix-based), it also depends on whether the module distribution being installed
+is pure Python or contains extensions ("non-pure"):
+
++-----------------+-----------------------------------------------------+--------------------------------------------------+-------+
+| Platform | Standard installation location | Default value | Notes |
++=================+=====================================================+==================================================+=======+
+| Unix (pure) | :file:`{prefix}/lib/python{X.Y}/site-packages` | :file:`/usr/local/lib/python{X.Y}/site-packages` | \(1) |
++-----------------+-----------------------------------------------------+--------------------------------------------------+-------+
+| Unix (non-pure) | :file:`{exec-prefix}/lib/python{X.Y}/site-packages` | :file:`/usr/local/lib/python{X.Y}/site-packages` | \(1) |
++-----------------+-----------------------------------------------------+--------------------------------------------------+-------+
+| Windows | :file:`{prefix}` | :file:`C:\\Python` | \(2) |
++-----------------+-----------------------------------------------------+--------------------------------------------------+-------+
+
+Notes:
+
+(1)
+ Most Linux distributions include Python as a standard part of the system, so
+ :file:`{prefix}` and :file:`{exec-prefix}` are usually both :file:`/usr` on
+ Linux. If you build Python yourself on Linux (or any Unix-like system), the
+ default :file:`{prefix}` and :file:`{exec-prefix}` are :file:`/usr/local`.
+
+(2)
+ The default installation directory on Windows was :file:`C:\\Program
+ Files\\Python` under Python 1.6a1, 1.5.2, and earlier.
+
+:file:`{prefix}` and :file:`{exec-prefix}` stand for the directories that Python
+is installed to, and where it finds its libraries at run-time. They are always
+the same under Windows, and very often the same under Unix and Mac OS X. You
+can find out what your Python installation uses for :file:`{prefix}` and
+:file:`{exec-prefix}` by running Python in interactive mode and typing a few
+simple commands. Under Unix, just type ``python`` at the shell prompt. Under
+Windows, choose :menuselection:`Start --> Programs --> Python X.Y -->
+Python (command line)`. Once the interpreter is started, you type Python code
+at the prompt. For example, on my Linux system, I type the three Python
+statements shown below, and get the output as shown, to find out my
+:file:`{prefix}` and :file:`{exec-prefix}`::
+
+ Python 2.4 (#26, Aug 7 2004, 17:19:02)
+ Type "help", "copyright", "credits" or "license" for more information.
+ >>> import sys
+ >>> sys.prefix
+ '/usr'
+ >>> sys.exec_prefix
+ '/usr'
+
+If you don't want to install modules to the standard location, or if you don't
+have permission to write there, then you need to read about alternate
+installations in section :ref:`inst-alt-install`. If you want to customize your
+installation directories more heavily, see section :ref:`inst-custom-install` on
+custom installations.
+
+
+.. _inst-alt-install:
+
+Alternate Installation
+======================
+
+Often, it is necessary or desirable to install modules to a location other than
+the standard location for third-party Python modules. For example, on a Unix
+system you might not have permission to write to the standard third-party module
+directory. Or you might wish to try out a module before making it a standard
+part of your local Python installation. This is especially true when upgrading
+a distribution already present: you want to make sure your existing base of
+scripts still works with the new version before actually upgrading.
+
+The Distutils :command:`install` command is designed to make installing module
+distributions to an alternate location simple and painless. The basic idea is
+that you supply a base directory for the installation, and the
+:command:`install` command picks a set of directories (called an *installation
+scheme*) under this base directory in which to install files. The details
+differ across platforms, so read whichever of the following sections applies to
+you.
+
+
+.. _inst-alt-install-prefix:
+
+Alternate installation: the home scheme
+---------------------------------------
+
+The idea behind the "home scheme" is that you build and maintain a personal
+stash of Python modules. This scheme's name is derived from the idea of a
+"home" directory on Unix, since it's not unusual for a Unix user to make their
+home directory have a layout similar to :file:`/usr/` or :file:`/usr/local/`.
+This scheme can be used by anyone, regardless of the operating system their
+installing for.
+
+Installing a new module distribution is as simple as ::
+
+ python setup.py install --home=<dir>
+
+where you can supply any directory you like for the :option:`--home` option. On
+Unix, lazy typists can just type a tilde (``~``); the :command:`install` command
+will expand this to your home directory::
+
+ python setup.py install --home=~
+
+The :option:`--home` option defines the installation base directory. Files are
+installed to the following directories under the installation base as follows:
+
++------------------------------+---------------------------+-----------------------------+
+| Type of file | Installation Directory | Override option |
++==============================+===========================+=============================+
+| pure module distribution | :file:`{home}/lib/python` | :option:`--install-purelib` |
++------------------------------+---------------------------+-----------------------------+
+| non-pure module distribution | :file:`{home}/lib/python` | :option:`--install-platlib` |
++------------------------------+---------------------------+-----------------------------+
+| scripts | :file:`{home}/bin` | :option:`--install-scripts` |
++------------------------------+---------------------------+-----------------------------+
+| data | :file:`{home}/share` | :option:`--install-data` |
++------------------------------+---------------------------+-----------------------------+
+
+.. versionchanged:: 2.4
+ The :option:`--home` option used to be supported only on Unix.
+
+
+.. _inst-alt-install-home:
+
+Alternate installation: Unix (the prefix scheme)
+------------------------------------------------
+
+The "prefix scheme" is useful when you wish to use one Python installation to
+perform the build/install (i.e., to run the setup script), but install modules
+into the third-party module directory of a different Python installation (or
+something that looks like a different Python installation). If this sounds a
+trifle unusual, it is---that's why the "home scheme" comes first. However,
+there are at least two known cases where the prefix scheme will be useful.
+
+First, consider that many Linux distributions put Python in :file:`/usr`, rather
+than the more traditional :file:`/usr/local`. This is entirely appropriate,
+since in those cases Python is part of "the system" rather than a local add-on.
+However, if you are installing Python modules from source, you probably want
+them to go in :file:`/usr/local/lib/python2.{X}` rather than
+:file:`/usr/lib/python2.{X}`. This can be done with ::
+
+ /usr/bin/python setup.py install --prefix=/usr/local
+
+Another possibility is a network filesystem where the name used to write to a
+remote directory is different from the name used to read it: for example, the
+Python interpreter accessed as :file:`/usr/local/bin/python` might search for
+modules in :file:`/usr/local/lib/python2.{X}`, but those modules would have to
+be installed to, say, :file:`/mnt/{@server}/export/lib/python2.{X}`. This could
+be done with ::
+
+ /usr/local/bin/python setup.py install --prefix=/mnt/@server/export
+
+In either case, the :option:`--prefix` option defines the installation base, and
+the :option:`--exec-prefix` option defines the platform-specific installation
+base, which is used for platform-specific files. (Currently, this just means
+non-pure module distributions, but could be expanded to C libraries, binary
+executables, etc.) If :option:`--exec-prefix` is not supplied, it defaults to
+:option:`--prefix`. Files are installed as follows:
+
++------------------------------+-----------------------------------------------------+-----------------------------+
+| Type of file | Installation Directory | Override option |
++==============================+=====================================================+=============================+
+| pure module distribution | :file:`{prefix}/lib/python{X.Y}/site-packages` | :option:`--install-purelib` |
++------------------------------+-----------------------------------------------------+-----------------------------+
+| non-pure module distribution | :file:`{exec-prefix}/lib/python{X.Y}/site-packages` | :option:`--install-platlib` |
++------------------------------+-----------------------------------------------------+-----------------------------+
+| scripts | :file:`{prefix}/bin` | :option:`--install-scripts` |
++------------------------------+-----------------------------------------------------+-----------------------------+
+| data | :file:`{prefix}/share` | :option:`--install-data` |
++------------------------------+-----------------------------------------------------+-----------------------------+
+
+There is no requirement that :option:`--prefix` or :option:`--exec-prefix`
+actually point to an alternate Python installation; if the directories listed
+above do not already exist, they are created at installation time.
+
+Incidentally, the real reason the prefix scheme is important is simply that a
+standard Unix installation uses the prefix scheme, but with :option:`--prefix`
+and :option:`--exec-prefix` supplied by Python itself as ``sys.prefix`` and
+``sys.exec_prefix``. Thus, you might think you'll never use the prefix scheme,
+but every time you run ``python setup.py install`` without any other options,
+you're using it.
+
+Note that installing extensions to an alternate Python installation has no
+effect on how those extensions are built: in particular, the Python header files
+(:file:`Python.h` and friends) installed with the Python interpreter used to run
+the setup script will be used in compiling extensions. It is your
+responsibility to ensure that the interpreter used to run extensions installed
+in this way is compatible with the interpreter used to build them. The best way
+to do this is to ensure that the two interpreters are the same version of Python
+(possibly different builds, or possibly copies of the same build). (Of course,
+if your :option:`--prefix` and :option:`--exec-prefix` don't even point to an
+alternate Python installation, this is immaterial.)
+
+
+.. _inst-alt-install-windows:
+
+Alternate installation: Windows (the prefix scheme)
+---------------------------------------------------
+
+Windows has no concept of a user's home directory, and since the standard Python
+installation under Windows is simpler than under Unix, the :option:`--prefix`
+option has traditionally been used to install additional packages in separate
+locations on Windows. ::
+
+ python setup.py install --prefix="\Temp\Python"
+
+to install modules to the :file:`\\Temp\\Python` directory on the current drive.
+
+The installation base is defined by the :option:`--prefix` option; the
+:option:`--exec-prefix` option is not supported under Windows. Files are
+installed as follows:
+
++------------------------------+---------------------------+-----------------------------+
+| Type of file | Installation Directory | Override option |
++==============================+===========================+=============================+
+| pure module distribution | :file:`{prefix}` | :option:`--install-purelib` |
++------------------------------+---------------------------+-----------------------------+
+| non-pure module distribution | :file:`{prefix}` | :option:`--install-platlib` |
++------------------------------+---------------------------+-----------------------------+
+| scripts | :file:`{prefix}\\Scripts` | :option:`--install-scripts` |
++------------------------------+---------------------------+-----------------------------+
+| data | :file:`{prefix}\\Data` | :option:`--install-data` |
++------------------------------+---------------------------+-----------------------------+
+
+
+.. _inst-custom-install:
+
+Custom Installation
+===================
+
+Sometimes, the alternate installation schemes described in section
+:ref:`inst-alt-install` just don't do what you want. You might want to tweak just
+one or two directories while keeping everything under the same base directory,
+or you might want to completely redefine the installation scheme. In either
+case, you're creating a *custom installation scheme*.
+
+You probably noticed the column of "override options" in the tables describing
+the alternate installation schemes above. Those options are how you define a
+custom installation scheme. These override options can be relative, absolute,
+or explicitly defined in terms of one of the installation base directories.
+(There are two installation base directories, and they are normally the same---
+they only differ when you use the Unix "prefix scheme" and supply different
+:option:`--prefix` and :option:`--exec-prefix` options.)
+
+For example, say you're installing a module distribution to your home directory
+under Unix---but you want scripts to go in :file:`~/scripts` rather than
+:file:`~/bin`. As you might expect, you can override this directory with the
+:option:`--install-scripts` option; in this case, it makes most sense to supply
+a relative path, which will be interpreted relative to the installation base
+directory (your home directory, in this case)::
+
+ python setup.py install --home=~ --install-scripts=scripts
+
+Another Unix example: suppose your Python installation was built and installed
+with a prefix of :file:`/usr/local/python`, so under a standard installation
+scripts will wind up in :file:`/usr/local/python/bin`. If you want them in
+:file:`/usr/local/bin` instead, you would supply this absolute directory for the
+:option:`--install-scripts` option::
+
+ python setup.py install --install-scripts=/usr/local/bin
+
+(This performs an installation using the "prefix scheme," where the prefix is
+whatever your Python interpreter was installed with--- :file:`/usr/local/python`
+in this case.)
+
+If you maintain Python on Windows, you might want third-party modules to live in
+a subdirectory of :file:`{prefix}`, rather than right in :file:`{prefix}`
+itself. This is almost as easy as customizing the script installation directory
+---you just have to remember that there are two types of modules to worry about,
+pure modules and non-pure modules (i.e., modules from a non-pure distribution).
+For example::
+
+ python setup.py install --install-purelib=Site --install-platlib=Site
+
+The specified installation directories are relative to :file:`{prefix}`. Of
+course, you also have to ensure that these directories are in Python's module
+search path, such as by putting a :file:`.pth` file in :file:`{prefix}`. See
+section :ref:`inst-search-path` to find out how to modify Python's search path.
+
+If you want to define an entire installation scheme, you just have to supply all
+of the installation directory options. The recommended way to do this is to
+supply relative paths; for example, if you want to maintain all Python
+module-related files under :file:`python` in your home directory, and you want a
+separate directory for each platform that you use your home directory from, you
+might define the following installation scheme::
+
+ python setup.py install --home=~ \
+ --install-purelib=python/lib \
+ --install-platlib=python/lib.$PLAT \
+ --install-scripts=python/scripts
+ --install-data=python/data
+
+or, equivalently,
+
+.. % $ % -- bow to font-lock
+
+::
+
+ python setup.py install --home=~/python \
+ --install-purelib=lib \
+ --install-platlib='lib.$PLAT' \
+ --install-scripts=scripts
+ --install-data=data
+
+``$PLAT`` is not (necessarily) an environment variable---it will be expanded by
+the Distutils as it parses your command line options, just as it does when
+parsing your configuration file(s).
+
+.. % $ % -- bow to font-lock
+
+Obviously, specifying the entire installation scheme every time you install a
+new module distribution would be very tedious. Thus, you can put these options
+into your Distutils config file (see section :ref:`inst-config-files`)::
+
+ [install]
+ install-base=$HOME
+ install-purelib=python/lib
+ install-platlib=python/lib.$PLAT
+ install-scripts=python/scripts
+ install-data=python/data
+
+or, equivalently, ::
+
+ [install]
+ install-base=$HOME/python
+ install-purelib=lib
+ install-platlib=lib.$PLAT
+ install-scripts=scripts
+ install-data=data
+
+Note that these two are *not* equivalent if you supply a different installation
+base directory when you run the setup script. For example, ::
+
+ python setup.py install --install-base=/tmp
+
+would install pure modules to :file:`{/tmp/python/lib}` in the first case, and
+to :file:`{/tmp/lib}` in the second case. (For the second case, you probably
+want to supply an installation base of :file:`/tmp/python`.)
+
+You probably noticed the use of ``$HOME`` and ``$PLAT`` in the sample
+configuration file input. These are Distutils configuration variables, which
+bear a strong resemblance to environment variables. In fact, you can use
+environment variables in config files on platforms that have such a notion but
+the Distutils additionally define a few extra variables that may not be in your
+environment, such as ``$PLAT``. (And of course, on systems that don't have
+environment variables, such as Mac OS 9, the configuration variables supplied by
+the Distutils are the only ones you can use.) See section :ref:`inst-config-files`
+for details.
+
+.. % XXX need some Windows examples---when would custom
+.. % installation schemes be needed on those platforms?
+
+.. % XXX I'm not sure where this section should go.
+
+
+.. _inst-search-path:
+
+Modifying Python's Search Path
+------------------------------
+
+When the Python interpreter executes an :keyword:`import` statement, it searches
+for both Python code and extension modules along a search path. A default value
+for the path is configured into the Python binary when the interpreter is built.
+You can determine the path by importing the :mod:`sys` module and printing the
+value of ``sys.path``. ::
+
+ $ python
+ Python 2.2 (#11, Oct 3 2002, 13:31:27)
+ [GCC 2.96 20000731 (Red Hat Linux 7.3 2.96-112)] on linux2
+ Type ``help'', ``copyright'', ``credits'' or ``license'' for more information.
+ >>> import sys
+ >>> sys.path
+ ['', '/usr/local/lib/python2.3', '/usr/local/lib/python2.3/plat-linux2',
+ '/usr/local/lib/python2.3/lib-tk', '/usr/local/lib/python2.3/lib-dynload',
+ '/usr/local/lib/python2.3/site-packages']
+ >>>
+
+The null string in ``sys.path`` represents the current working directory.
+
+.. % $ <-- bow to font-lock
+
+The expected convention for locally installed packages is to put them in the
+:file:`{...}/site-packages/` directory, but you may want to install Python
+modules into some arbitrary directory. For example, your site may have a
+convention of keeping all software related to the web server under :file:`/www`.
+Add-on Python modules might then belong in :file:`/www/python`, and in order to
+import them, this directory must be added to ``sys.path``. There are several
+different ways to add the directory.
+
+The most convenient way is to add a path configuration file to a directory
+that's already on Python's path, usually to the :file:`.../site-packages/`
+directory. Path configuration files have an extension of :file:`.pth`, and each
+line must contain a single path that will be appended to ``sys.path``. (Because
+the new paths are appended to ``sys.path``, modules in the added directories
+will not override standard modules. This means you can't use this mechanism for
+installing fixed versions of standard modules.)
+
+Paths can be absolute or relative, in which case they're relative to the
+directory containing the :file:`.pth` file. Any directories added to the search
+path will be scanned in turn for :file:`.pth` files. See `site module
+documentation <http://www.python.org/dev/doc/devel/lib/module-site.html>`_ for
+more information.
+
+A slightly less convenient way is to edit the :file:`site.py` file in Python's
+standard library, and modify ``sys.path``. :file:`site.py` is automatically
+imported when the Python interpreter is executed, unless the :option:`-S` switch
+is supplied to suppress this behaviour. So you could simply edit
+:file:`site.py` and add two lines to it::
+
+ import sys
+ sys.path.append('/www/python/')
+
+However, if you reinstall the same major version of Python (perhaps when
+upgrading from 2.2 to 2.2.2, for example) :file:`site.py` will be overwritten by
+the stock version. You'd have to remember that it was modified and save a copy
+before doing the installation.
+
+There are two environment variables that can modify ``sys.path``.
+:envvar:`PYTHONHOME` sets an alternate value for the prefix of the Python
+installation. For example, if :envvar:`PYTHONHOME` is set to ``/www/python``,
+the search path will be set to ``['', '/www/python/lib/pythonX.Y/',
+'/www/python/lib/pythonX.Y/plat-linux2', ...]``.
+
+The :envvar:`PYTHONPATH` variable can be set to a list of paths that will be
+added to the beginning of ``sys.path``. For example, if :envvar:`PYTHONPATH` is
+set to ``/www/python:/opt/py``, the search path will begin with
+``['/www/python', '/opt/py']``. (Note that directories must exist in order to
+be added to ``sys.path``; the :mod:`site` module removes paths that don't
+exist.)
+
+Finally, ``sys.path`` is just a regular Python list, so any Python application
+can modify it by adding or removing entries.
+
+
+.. _inst-config-files:
+
+Distutils Configuration Files
+=============================
+
+As mentioned above, you can use Distutils configuration files to record personal
+or site preferences for any Distutils options. That is, any option to any
+command can be stored in one of two or three (depending on your platform)
+configuration files, which will be consulted before the command-line is parsed.
+This means that configuration files will override default values, and the
+command-line will in turn override configuration files. Furthermore, if
+multiple configuration files apply, values from "earlier" files are overridden
+by "later" files.
+
+
+.. _inst-config-filenames:
+
+Location and names of config files
+----------------------------------
+
+The names and locations of the configuration files vary slightly across
+platforms. On Unix and Mac OS X, the three configuration files (in the order
+they are processed) are:
+
++--------------+----------------------------------------------------------+-------+
+| Type of file | Location and filename | Notes |
++==============+==========================================================+=======+
+| system | :file:`{prefix}/lib/python{ver}/distutils/distutils.cfg` | \(1) |
++--------------+----------------------------------------------------------+-------+
+| personal | :file:`$HOME/.pydistutils.cfg` | \(2) |
++--------------+----------------------------------------------------------+-------+
+| local | :file:`setup.cfg` | \(3) |
++--------------+----------------------------------------------------------+-------+
+
+And on Windows, the configuration files are:
+
++--------------+-------------------------------------------------+-------+
+| Type of file | Location and filename | Notes |
++==============+=================================================+=======+
+| system | :file:`{prefix}\\Lib\\distutils\\distutils.cfg` | \(4) |
++--------------+-------------------------------------------------+-------+
+| personal | :file:`%HOME%\\pydistutils.cfg` | \(5) |
++--------------+-------------------------------------------------+-------+
+| local | :file:`setup.cfg` | \(3) |
++--------------+-------------------------------------------------+-------+
+
+Notes:
+
+(1)
+ Strictly speaking, the system-wide configuration file lives in the directory
+ where the Distutils are installed; under Python 1.6 and later on Unix, this is
+ as shown. For Python 1.5.2, the Distutils will normally be installed to
+ :file:`{prefix}/lib/python1.5/site-packages/distutils`, so the system
+ configuration file should be put there under Python 1.5.2.
+
+(2)
+ On Unix, if the :envvar:`HOME` environment variable is not defined, the user's
+ home directory will be determined with the :func:`getpwuid` function from the
+ standard :mod:`pwd` module.
+
+(3)
+ I.e., in the current directory (usually the location of the setup script).
+
+(4)
+ (See also note (1).) Under Python 1.6 and later, Python's default "installation
+ prefix" is :file:`C:\\Python`, so the system configuration file is normally
+ :file:`C:\\Python\\Lib\\distutils\\distutils.cfg`. Under Python 1.5.2, the
+ default prefix was :file:`C:\\Program Files\\Python`, and the Distutils were not
+ part of the standard library---so the system configuration file would be
+ :file:`C:\\Program Files\\Python\\distutils\\distutils.cfg` in a standard Python
+ 1.5.2 installation under Windows.
+
+(5)
+ On Windows, if the :envvar:`HOME` environment variable is not defined, no
+ personal configuration file will be found or used. (In other words, the
+ Distutils make no attempt to guess your home directory on Windows.)
+
+
+.. _inst-config-syntax:
+
+Syntax of config files
+----------------------
+
+The Distutils configuration files all have the same syntax. The config files
+are grouped into sections. There is one section for each Distutils command,
+plus a ``global`` section for global options that affect every command. Each
+section consists of one option per line, specified as ``option=value``.
+
+For example, the following is a complete config file that just forces all
+commands to run quietly by default::
+
+ [global]
+ verbose=0
+
+If this is installed as the system config file, it will affect all processing of
+any Python module distribution by any user on the current system. If it is
+installed as your personal config file (on systems that support them), it will
+affect only module distributions processed by you. And if it is used as the
+:file:`setup.cfg` for a particular module distribution, it affects only that
+distribution.
+
+You could override the default "build base" directory and make the
+:command:`build\*` commands always forcibly rebuild all files with the
+following::
+
+ [build]
+ build-base=blib
+ force=1
+
+which corresponds to the command-line arguments ::
+
+ python setup.py build --build-base=blib --force
+
+except that including the :command:`build` command on the command-line means
+that command will be run. Including a particular command in config files has no
+such implication; it only means that if the command is run, the options in the
+config file will apply. (Or if other commands that derive values from it are
+run, they will use the values in the config file.)
+
+You can find out the complete list of options for any command using the
+:option:`--help` option, e.g.::
+
+ python setup.py build --help
+
+and you can find out the complete list of global options by using
+:option:`--help` without a command::
+
+ python setup.py --help
+
+See also the "Reference" section of the "Distributing Python Modules" manual.
+
+
+.. _inst-building-ext:
+
+Building Extensions: Tips and Tricks
+====================================
+
+Whenever possible, the Distutils try to use the configuration information made
+available by the Python interpreter used to run the :file:`setup.py` script.
+For example, the same compiler and linker flags used to compile Python will also
+be used for compiling extensions. Usually this will work well, but in
+complicated situations this might be inappropriate. This section discusses how
+to override the usual Distutils behaviour.
+
+
+.. _inst-tweak-flags:
+
+Tweaking compiler/linker flags
+------------------------------
+
+Compiling a Python extension written in C or C++ will sometimes require
+specifying custom flags for the compiler and linker in order to use a particular
+library or produce a special kind of object code. This is especially true if the
+extension hasn't been tested on your platform, or if you're trying to
+cross-compile Python.
+
+In the most general case, the extension author might have foreseen that
+compiling the extensions would be complicated, and provided a :file:`Setup` file
+for you to edit. This will likely only be done if the module distribution
+contains many separate extension modules, or if they often require elaborate
+sets of compiler flags in order to work.
+
+A :file:`Setup` file, if present, is parsed in order to get a list of extensions
+to build. Each line in a :file:`Setup` describes a single module. Lines have
+the following structure::
+
+ module ... [sourcefile ...] [cpparg ...] [library ...]
+
+
+Let's examine each of the fields in turn.
+
+* *module* is the name of the extension module to be built, and should be a
+ valid Python identifier. You can't just change this in order to rename a module
+ (edits to the source code would also be needed), so this should be left alone.
+
+* *sourcefile* is anything that's likely to be a source code file, at least
+ judging by the filename. Filenames ending in :file:`.c` are assumed to be
+ written in C, filenames ending in :file:`.C`, :file:`.cc`, and :file:`.c++` are
+ assumed to be C++, and filenames ending in :file:`.m` or :file:`.mm` are assumed
+ to be in Objective C.
+
+* *cpparg* is an argument for the C preprocessor, and is anything starting with
+ :option:`-I`, :option:`-D`, :option:`-U` or :option:`-C`.
+
+* *library* is anything ending in :file:`.a` or beginning with :option:`-l` or
+ :option:`-L`.
+
+If a particular platform requires a special library on your platform, you can
+add it by editing the :file:`Setup` file and running ``python setup.py build``.
+For example, if the module defined by the line ::
+
+ foo foomodule.c
+
+must be linked with the math library :file:`libm.a` on your platform, simply add
+:option:`-lm` to the line::
+
+ foo foomodule.c -lm
+
+Arbitrary switches intended for the compiler or the linker can be supplied with
+the :option:`-Xcompiler` *arg* and :option:`-Xlinker` *arg* options::
+
+ foo foomodule.c -Xcompiler -o32 -Xlinker -shared -lm
+
+The next option after :option:`-Xcompiler` and :option:`-Xlinker` will be
+appended to the proper command line, so in the above example the compiler will
+be passed the :option:`-o32` option, and the linker will be passed
+:option:`-shared`. If a compiler option requires an argument, you'll have to
+supply multiple :option:`-Xcompiler` options; for example, to pass ``-x c++``
+the :file:`Setup` file would have to contain ``-Xcompiler -x -Xcompiler c++``.
+
+Compiler flags can also be supplied through setting the :envvar:`CFLAGS`
+environment variable. If set, the contents of :envvar:`CFLAGS` will be added to
+the compiler flags specified in the :file:`Setup` file.
+
+
+.. _inst-non-ms-compilers:
+
+Using non-Microsoft compilers on Windows
+----------------------------------------
+
+.. sectionauthor:: Rene Liebscher <R.Liebscher@gmx.de>
+
+
+
+Borland C++
+^^^^^^^^^^^
+
+This subsection describes the necessary steps to use Distutils with the Borland
+C++ compiler version 5.5. First you have to know that Borland's object file
+format (OMF) is different from the format used by the Python version you can
+download from the Python or ActiveState Web site. (Python is built with
+Microsoft Visual C++, which uses COFF as the object file format.) For this
+reason you have to convert Python's library :file:`python25.lib` into the
+Borland format. You can do this as follows:
+
+.. % Should we mention that users have to create cfg-files for the compiler?
+.. % see also http://community.borland.com/article/0,1410,21205,00.html
+
+::
+
+ coff2omf python25.lib python25_bcpp.lib
+
+The :file:`coff2omf` program comes with the Borland compiler. The file
+:file:`python25.lib` is in the :file:`Libs` directory of your Python
+installation. If your extension uses other libraries (zlib, ...) you have to
+convert them too.
+
+The converted files have to reside in the same directories as the normal
+libraries.
+
+How does Distutils manage to use these libraries with their changed names? If
+the extension needs a library (eg. :file:`foo`) Distutils checks first if it
+finds a library with suffix :file:`_bcpp` (eg. :file:`foo_bcpp.lib`) and then
+uses this library. In the case it doesn't find such a special library it uses
+the default name (:file:`foo.lib`.) [#]_
+
+To let Distutils compile your extension with Borland C++ you now have to type::
+
+ python setup.py build --compiler=bcpp
+
+If you want to use the Borland C++ compiler as the default, you could specify
+this in your personal or system-wide configuration file for Distutils (see
+section :ref:`inst-config-files`.)
+
+
+.. seealso::
+
+ `C++Builder Compiler <http://www.borland.com/bcppbuilder/freecompiler/>`_
+ Information about the free C++ compiler from Borland, including links to the
+ download pages.
+
+ `Creating Python Extensions Using Borland's Free Compiler <http://www.cyberus.ca/~g_will/pyExtenDL.shtml>`_
+ Document describing how to use Borland's free command-line C++ compiler to build
+ Python.
+
+
+GNU C / Cygwin / MinGW
+^^^^^^^^^^^^^^^^^^^^^^
+
+These instructions only apply if you're using a version of Python prior to
+2.4.1 with a MinGW prior to 3.0.0 (with binutils-2.13.90-20030111-1).
+
+This section describes the necessary steps to use Distutils with the GNU C/C++
+compilers in their Cygwin and MinGW distributions. [#]_ For a Python interpreter
+that was built with Cygwin, everything should work without any of these
+following steps.
+
+These compilers require some special libraries. This task is more complex than
+for Borland's C++, because there is no program to convert the library. First
+you have to create a list of symbols which the Python DLL exports. (You can find
+a good program for this task at
+http://starship.python.net/crew/kernr/mingw32/Notes.html, see at PExports 0.42h
+there.)
+
+.. % I don't understand what the next line means. --amk
+.. % (inclusive the references on data structures.)
+
+::
+
+ pexports python25.dll >python25.def
+
+The location of an installed :file:`python25.dll` will depend on the
+installation options and the version and language of Windows. In a "just for
+me" installation, it will appear in the root of the installation directory. In
+a shared installation, it will be located in the system directory.
+
+Then you can create from these information an import library for gcc. ::
+
+ /cygwin/bin/dlltool --dllname python25.dll --def python25.def --output-lib libpython25.a
+
+The resulting library has to be placed in the same directory as
+:file:`python25.lib`. (Should be the :file:`libs` directory under your Python
+installation directory.)
+
+If your extension uses other libraries (zlib,...) you might have to convert
+them too. The converted files have to reside in the same directories as the
+normal libraries do.
+
+To let Distutils compile your extension with Cygwin you now have to type ::
+
+ python setup.py build --compiler=cygwin
+
+and for Cygwin in no-cygwin mode [#]_ or for MinGW type::
+
+ python setup.py build --compiler=mingw32
+
+If you want to use any of these options/compilers as default, you should
+consider to write it in your personal or system-wide configuration file for
+Distutils (see section :ref:`inst-config-files`.)
+
+
+.. seealso::
+
+ `Building Python modules on MS Windows platform with MinGW <http://www.zope.org/Members/als/tips/win32_mingw_modules>`_
+ Information about building the required libraries for the MinGW environment.
+
+ http://pyopengl.sourceforge.net/ftp/win32-stuff/
+ Converted import libraries in Cygwin/MinGW and Borland format, and a script to
+ create the registry entries needed for Distutils to locate the built Python.
+
+.. rubric:: Footnotes
+
+.. [#] This also means you could replace all existing COFF-libraries with OMF-libraries
+ of the same name.
+
+.. [#] Check http://sources.redhat.com/cygwin/ and http://www.mingw.org/ for more
+ information
+
+.. [#] Then you have no POSIX emulation available, but you also don't need
+ :file:`cygwin1.dll`.
diff --git a/Doc/library/__builtin__.rst b/Doc/library/__builtin__.rst
new file mode 100644
index 0000000000..b3e1e1188d
--- /dev/null
+++ b/Doc/library/__builtin__.rst
@@ -0,0 +1,41 @@
+
+:mod:`__builtin__` --- Built-in objects
+=======================================
+
+.. module:: __builtin__
+ :synopsis: The module that provides the built-in namespace.
+
+
+This module provides direct access to all 'built-in' identifiers of Python; for
+example, ``__builtin__.open`` is the full name for the built-in function
+:func:`open`. See chapter :ref:`builtin`.
+
+This module is not normally accessed explicitly by most applications, but can be
+useful in modules that provide objects with the same name as a built-in value,
+but in which the built-in of that name is also needed. For example, in a module
+that wants to implement an :func:`open` function that wraps the built-in
+:func:`open`, this module can be used directly::
+
+ import __builtin__
+
+ def open(path):
+ f = __builtin__.open(path, 'r')
+ return UpperCaser(f)
+
+ class UpperCaser:
+ '''Wrapper around a file that converts output to upper-case.'''
+
+ def __init__(self, f):
+ self._f = f
+
+ def read(self, count=-1):
+ return self._f.read(count).upper()
+
+ # ...
+
+As an implementation detail, most modules have the name ``__builtins__`` (note
+the ``'s'``) made available as part of their globals. The value of
+``__builtins__`` is normally either this module or the value of this modules's
+:attr:`__dict__` attribute. Since this is an implementation detail, it may not
+be used by alternate implementations of Python.
+
diff --git a/Doc/library/__future__.rst b/Doc/library/__future__.rst
new file mode 100644
index 0000000000..6bf2830c29
--- /dev/null
+++ b/Doc/library/__future__.rst
@@ -0,0 +1,61 @@
+
+:mod:`__future__` --- Future statement definitions
+==================================================
+
+.. module:: __future__
+ :synopsis: Future statement definitions
+
+
+:mod:`__future__` is a real module, and serves three purposes:
+
+* To avoid confusing existing tools that analyze import statements and expect to
+ find the modules they're importing.
+
+* To ensure that future_statements run under releases prior to 2.1 at least
+ yield runtime exceptions (the import of :mod:`__future__` will fail, because
+ there was no module of that name prior to 2.1).
+
+* To document when incompatible changes were introduced, and when they will be
+ --- or were --- made mandatory. This is a form of executable documentation, and
+ can be inspected programatically via importing :mod:`__future__` and examining
+ its contents.
+
+Each statement in :file:`__future__.py` is of the form::
+
+ FeatureName = "_Feature(" OptionalRelease "," MandatoryRelease ","
+ CompilerFlag ")"
+
+
+where, normally, *OptionalRelease* is less than *MandatoryRelease*, and both are
+5-tuples of the same form as ``sys.version_info``::
+
+ (PY_MAJOR_VERSION, # the 2 in 2.1.0a3; an int
+ PY_MINOR_VERSION, # the 1; an int
+ PY_MICRO_VERSION, # the 0; an int
+ PY_RELEASE_LEVEL, # "alpha", "beta", "candidate" or "final"; string
+ PY_RELEASE_SERIAL # the 3; an int
+ )
+
+*OptionalRelease* records the first release in which the feature was accepted.
+
+In the case of a *MandatoryRelease* that has not yet occurred,
+*MandatoryRelease* predicts the release in which the feature will become part of
+the language.
+
+Else *MandatoryRelease* records when the feature became part of the language; in
+releases at or after that, modules no longer need a future statement to use the
+feature in question, but may continue to use such imports.
+
+*MandatoryRelease* may also be ``None``, meaning that a planned feature got
+dropped.
+
+Instances of class :class:`_Feature` have two corresponding methods,
+:meth:`getOptionalRelease` and :meth:`getMandatoryRelease`.
+
+*CompilerFlag* is the (bitfield) flag that should be passed in the fourth
+argument to the builtin function :func:`compile` to enable the feature in
+dynamically compiled code. This flag is stored in the :attr:`compiler_flag`
+attribute on :class:`_Feature` instances.
+
+No feature description will ever be deleted from :mod:`__future__`.
+
diff --git a/Doc/library/__main__.rst b/Doc/library/__main__.rst
new file mode 100644
index 0000000000..a1d3c24bea
--- /dev/null
+++ b/Doc/library/__main__.rst
@@ -0,0 +1,17 @@
+
+:mod:`__main__` --- Top-level script environment
+================================================
+
+.. module:: __main__
+ :synopsis: The environment where the top-level script is run.
+
+
+This module represents the (otherwise anonymous) scope in which the
+interpreter's main program executes --- commands read either from standard
+input, from a script file, or from an interactive prompt. It is this
+environment in which the idiomatic "conditional script" stanza causes a script
+to run::
+
+ if __name__ == "__main__":
+ main()
+
diff --git a/Doc/library/_ast.rst b/Doc/library/_ast.rst
new file mode 100644
index 0000000000..9b195be467
--- /dev/null
+++ b/Doc/library/_ast.rst
@@ -0,0 +1,59 @@
+.. _ast:
+
+Abstract Syntax Trees
+=====================
+
+.. module:: _ast
+ :synopsis: Abstract Syntax Tree classes.
+
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.5
+
+The ``_ast`` module helps Python applications to process trees of the Python
+abstract syntax grammar. The Python compiler currently provides read-only access
+to such trees, meaning that applications can only create a tree for a given
+piece of Python source code; generating byte code from a (potentially modified)
+tree is not supported. The abstract syntax itself might change with each Python
+release; this module helps to find out programmatically what the current grammar
+looks like.
+
+An abstract syntax tree can be generated by passing ``_ast.PyCF_ONLY_AST`` as a
+flag to the :func:`compile` builtin function. The result will be a tree of
+objects whose classes all inherit from ``_ast.AST``.
+
+The actual classes are derived from the ``Parser/Python.asdl`` file, which is
+reproduced below. There is one class defined for each left-hand side symbol in
+the abstract grammar (for example, ``_ast.stmt`` or ``_ast.expr``). In addition,
+there is one class defined for each constructor on the right-hand side; these
+classes inherit from the classes for the left-hand side trees. For example,
+``_ast.BinOp`` inherits from ``_ast.expr``. For production rules with
+alternatives (aka "sums"), the left-hand side class is abstract: only instances
+of specific constructor nodes are ever created.
+
+Each concrete class has an attribute ``_fields`` which gives the names of all
+child nodes.
+
+Each instance of a concrete class has one attribute for each child node, of the
+type as defined in the grammar. For example, ``_ast.BinOp`` instances have an
+attribute ``left`` of type ``_ast.expr``. Instances of ``_ast.expr`` and
+``_ast.stmt`` subclasses also have lineno and col_offset attributes. The lineno
+is the line number of source text (1 indexed so the first line is line 1) and
+the col_offset is the utf8 byte offset of the first token that generated the
+node. The utf8 offset is recorded because the parser uses utf8 internally.
+
+If these attributes are marked as optional in the grammar (using a question
+mark), the value might be ``None``. If the attributes can have zero-or-more
+values (marked with an asterisk), the values are represented as Python lists.
+
+
+Abstract Grammar
+----------------
+
+The module defines a string constant ``__version__`` which is the decimal
+subversion revision number of the file shown below.
+
+The abstract grammar is currently defined as follows:
+
+.. literalinclude:: ../../Parser/Python.asdl
diff --git a/Doc/library/_winreg.rst b/Doc/library/_winreg.rst
new file mode 100644
index 0000000000..fddbfd12a8
--- /dev/null
+++ b/Doc/library/_winreg.rst
@@ -0,0 +1,420 @@
+
+:mod:`_winreg` -- Windows registry access
+=========================================
+
+.. module:: _winreg
+ :platform: Windows
+ :synopsis: Routines and objects for manipulating the Windows registry.
+.. sectionauthor:: Mark Hammond <MarkH@ActiveState.com>
+
+
+.. versionadded:: 2.0
+
+These functions expose the Windows registry API to Python. Instead of using an
+integer as the registry handle, a handle object is used to ensure that the
+handles are closed correctly, even if the programmer neglects to explicitly
+close them.
+
+This module exposes a very low-level interface to the Windows registry; it is
+expected that in the future a new ``winreg`` module will be created offering a
+higher-level interface to the registry API.
+
+This module offers the following functions:
+
+
+.. function:: CloseKey(hkey)
+
+ Closes a previously opened registry key. The hkey argument specifies a
+ previously opened key.
+
+ Note that if *hkey* is not closed using this method (or via
+ :meth:`handle.Close`), it is closed when the *hkey* object is destroyed by
+ Python.
+
+
+.. function:: ConnectRegistry(computer_name, key)
+
+ Establishes a connection to a predefined registry handle on another computer,
+ and returns a :dfn:`handle object`
+
+ *computer_name* is the name of the remote computer, of the form
+ ``r"\\computername"``. If ``None``, the local computer is used.
+
+ *key* is the predefined handle to connect to.
+
+ The return value is the handle of the opened key. If the function fails, an
+ :exc:`EnvironmentError` exception is raised.
+
+
+.. function:: CreateKey(key, sub_key)
+
+ Creates or opens the specified key, returning a :dfn:`handle object`
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *sub_key* is a string that names the key this method opens or creates.
+
+ If *key* is one of the predefined keys, *sub_key* may be ``None``. In that
+ case, the handle returned is the same key handle passed in to the function.
+
+ If the key already exists, this function opens the existing key.
+
+ The return value is the handle of the opened key. If the function fails, an
+ :exc:`EnvironmentError` exception is raised.
+
+
+.. function:: DeleteKey(key, sub_key)
+
+ Deletes the specified key.
+
+ *key* is an already open key, or any one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *sub_key* is a string that must be a subkey of the key identified by the *key*
+ parameter. This value must not be ``None``, and the key may not have subkeys.
+
+ *This method can not delete keys with subkeys.*
+
+ If the method succeeds, the entire key, including all of its values, is removed.
+ If the method fails, an :exc:`EnvironmentError` exception is raised.
+
+
+.. function:: DeleteValue(key, value)
+
+ Removes a named value from a registry key.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *value* is a string that identifies the value to remove.
+
+
+.. function:: EnumKey(key, index)
+
+ Enumerates subkeys of an open registry key, returning a string.
+
+ *key* is an already open key, or any one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *index* is an integer that identifies the index of the key to retrieve.
+
+ The function retrieves the name of one subkey each time it is called. It is
+ typically called repeatedly until an :exc:`EnvironmentError` exception is
+ raised, indicating, no more values are available.
+
+
+.. function:: EnumValue(key, index)
+
+ Enumerates values of an open registry key, returning a tuple.
+
+ *key* is an already open key, or any one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *index* is an integer that identifies the index of the value to retrieve.
+
+ The function retrieves the name of one subkey each time it is called. It is
+ typically called repeatedly, until an :exc:`EnvironmentError` exception is
+ raised, indicating no more values.
+
+ The result is a tuple of 3 items:
+
+ +-------+--------------------------------------------+
+ | Index | Meaning |
+ +=======+============================================+
+ | ``0`` | A string that identifies the value name |
+ +-------+--------------------------------------------+
+ | ``1`` | An object that holds the value data, and |
+ | | whose type depends on the underlying |
+ | | registry type |
+ +-------+--------------------------------------------+
+ | ``2`` | An integer that identifies the type of the |
+ | | value data |
+ +-------+--------------------------------------------+
+
+
+.. function:: FlushKey(key)
+
+ Writes all the attributes of a key to the registry.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ It is not necessary to call RegFlushKey to change a key. Registry changes are
+ flushed to disk by the registry using its lazy flusher. Registry changes are
+ also flushed to disk at system shutdown. Unlike :func:`CloseKey`, the
+ :func:`FlushKey` method returns only when all the data has been written to the
+ registry. An application should only call :func:`FlushKey` if it requires
+ absolute certainty that registry changes are on disk.
+
+ .. note::
+
+ If you don't know whether a :func:`FlushKey` call is required, it probably
+ isn't.
+
+
+.. function:: RegLoadKey(key, sub_key, file_name)
+
+ Creates a subkey under the specified key and stores registration information
+ from a specified file into that subkey.
+
+ *key* is an already open key, or any of the predefined :const:`HKEY_\*`
+ constants.
+
+ *sub_key* is a string that identifies the sub_key to load.
+
+ *file_name* is the name of the file to load registry data from. This file must
+ have been created with the :func:`SaveKey` function. Under the file allocation
+ table (FAT) file system, the filename may not have an extension.
+
+ A call to LoadKey() fails if the calling process does not have the
+ :const:`SE_RESTORE_PRIVILEGE` privilege. Note that privileges are different than
+ permissions - see the Win32 documentation for more details.
+
+ If *key* is a handle returned by :func:`ConnectRegistry`, then the path
+ specified in *fileName* is relative to the remote computer.
+
+ The Win32 documentation implies *key* must be in the :const:`HKEY_USER` or
+ :const:`HKEY_LOCAL_MACHINE` tree. This may or may not be true.
+
+
+.. function:: OpenKey(key, sub_key[, res=0][, sam=KEY_READ])
+
+ Opens the specified key, returning a :dfn:`handle object`
+
+ *key* is an already open key, or any one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *sub_key* is a string that identifies the sub_key to open.
+
+ *res* is a reserved integer, and must be zero. The default is zero.
+
+ *sam* is an integer that specifies an access mask that describes the desired
+ security access for the key. Default is :const:`KEY_READ`
+
+ The result is a new handle to the specified key.
+
+ If the function fails, :exc:`EnvironmentError` is raised.
+
+
+.. function:: OpenKeyEx()
+
+ The functionality of :func:`OpenKeyEx` is provided via :func:`OpenKey`, by the
+ use of default arguments.
+
+
+.. function:: QueryInfoKey(key)
+
+ Returns information about a key, as a tuple.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ The result is a tuple of 3 items:
+
+ +-------+---------------------------------------------+
+ | Index | Meaning |
+ +=======+=============================================+
+ | ``0`` | An integer giving the number of sub keys |
+ | | this key has. |
+ +-------+---------------------------------------------+
+ | ``1`` | An integer giving the number of values this |
+ | | key has. |
+ +-------+---------------------------------------------+
+ | ``2`` | A long integer giving when the key was last |
+ | | modified (if available) as 100's of |
+ | | nanoseconds since Jan 1, 1600. |
+ +-------+---------------------------------------------+
+
+
+.. function:: QueryValue(key, sub_key)
+
+ Retrieves the unnamed value for a key, as a string
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *sub_key* is a string that holds the name of the subkey with which the value is
+ associated. If this parameter is ``None`` or empty, the function retrieves the
+ value set by the :func:`SetValue` method for the key identified by *key*.
+
+ Values in the registry have name, type, and data components. This method
+ retrieves the data for a key's first value that has a NULL name. But the
+ underlying API call doesn't return the type, Lame Lame Lame, DO NOT USE THIS!!!
+
+
+.. function:: QueryValueEx(key, value_name)
+
+ Retrieves the type and data for a specified value name associated with an open
+ registry key.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *value_name* is a string indicating the value to query.
+
+ The result is a tuple of 2 items:
+
+ +-------+-----------------------------------------+
+ | Index | Meaning |
+ +=======+=========================================+
+ | ``0`` | The value of the registry item. |
+ +-------+-----------------------------------------+
+ | ``1`` | An integer giving the registry type for |
+ | | this value. |
+ +-------+-----------------------------------------+
+
+
+.. function:: SaveKey(key, file_name)
+
+ Saves the specified key, and all its subkeys to the specified file.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *file_name* is the name of the file to save registry data to. This file cannot
+ already exist. If this filename includes an extension, it cannot be used on file
+ allocation table (FAT) file systems by the :meth:`LoadKey`, :meth:`ReplaceKey`
+ or :meth:`RestoreKey` methods.
+
+ If *key* represents a key on a remote computer, the path described by
+ *file_name* is relative to the remote computer. The caller of this method must
+ possess the :const:`SeBackupPrivilege` security privilege. Note that
+ privileges are different than permissions - see the Win32 documentation for
+ more details.
+
+ This function passes NULL for *security_attributes* to the API.
+
+
+.. function:: SetValue(key, sub_key, type, value)
+
+ Associates a value with a specified key.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *sub_key* is a string that names the subkey with which the value is associated.
+
+ *type* is an integer that specifies the type of the data. Currently this must be
+ :const:`REG_SZ`, meaning only strings are supported. Use the :func:`SetValueEx`
+ function for support for other data types.
+
+ *value* is a string that specifies the new value.
+
+ If the key specified by the *sub_key* parameter does not exist, the SetValue
+ function creates it.
+
+ Value lengths are limited by available memory. Long values (more than 2048
+ bytes) should be stored as files with the filenames stored in the configuration
+ registry. This helps the registry perform efficiently.
+
+ The key identified by the *key* parameter must have been opened with
+ :const:`KEY_SET_VALUE` access.
+
+
+.. function:: SetValueEx(key, value_name, reserved, type, value)
+
+ Stores data in the value field of an open registry key.
+
+ *key* is an already open key, or one of the predefined :const:`HKEY_\*`
+ constants.
+
+ *value_name* is a string that names the subkey with which the value is
+ associated.
+
+ *type* is an integer that specifies the type of the data. This should be one
+ of the following constants defined in this module:
+
+ +----------------------------------+---------------------------------------------+
+ | Constant | Meaning |
+ +==================================+=============================================+
+ | :const:`REG_BINARY` | Binary data in any form. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_DWORD` | A 32-bit number. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_DWORD_LITTLE_ENDIAN` | A 32-bit number in little-endian format. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_DWORD_BIG_ENDIAN` | A 32-bit number in big-endian format. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_EXPAND_SZ` | Null-terminated string containing |
+ | | references to environment variables |
+ | | (``%PATH%``). |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_LINK` | A Unicode symbolic link. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_MULTI_SZ` | A sequence of null-terminated strings, |
+ | | terminated by two null characters. (Python |
+ | | handles this termination automatically.) |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_NONE` | No defined value type. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_RESOURCE_LIST` | A device-driver resource list. |
+ +----------------------------------+---------------------------------------------+
+ | :const:`REG_SZ` | A null-terminated string. |
+ +----------------------------------+---------------------------------------------+
+
+ *reserved* can be anything - zero is always passed to the API.
+
+ *value* is a string that specifies the new value.
+
+ This method can also set additional value and type information for the specified
+ key. The key identified by the key parameter must have been opened with
+ :const:`KEY_SET_VALUE` access.
+
+ To open the key, use the :func:`CreateKeyEx` or :func:`OpenKey` methods.
+
+ Value lengths are limited by available memory. Long values (more than 2048
+ bytes) should be stored as files with the filenames stored in the configuration
+ registry. This helps the registry perform efficiently.
+
+
+.. _handle-object:
+
+Registry Handle Objects
+-----------------------
+
+This object wraps a Windows HKEY object, automatically closing it when the
+object is destroyed. To guarantee cleanup, you can call either the
+:meth:`Close` method on the object, or the :func:`CloseKey` function.
+
+All registry functions in this module return one of these objects.
+
+All registry functions in this module which accept a handle object also accept
+an integer, however, use of the handle object is encouraged.
+
+Handle objects provide semantics for :meth:`__bool__` - thus ::
+
+ if handle:
+ print "Yes"
+
+will print ``Yes`` if the handle is currently valid (has not been closed or
+detached).
+
+The object also support comparison semantics, so handle objects will compare
+true if they both reference the same underlying Windows handle value.
+
+Handle objects can be converted to an integer (e.g., using the builtin
+:func:`int` function), in which case the underlying Windows handle value is
+returned. You can also use the :meth:`Detach` method to return the integer
+handle, and also disconnect the Windows handle from the handle object.
+
+
+.. method:: PyHKEY.Close()
+
+ Closes the underlying Windows handle.
+
+ If the handle is already closed, no error is raised.
+
+
+.. method:: PyHKEY.Detach()
+
+ Detaches the Windows handle from the handle object.
+
+ The result is an integer (or long on 64 bit Windows) that holds the value of the
+ handle before it is detached. If the handle is already detached or closed, this
+ will return zero.
+
+ After calling this function, the handle is effectively invalidated, but the
+ handle is not closed. You would call this function when you need the
+ underlying Win32 handle to exist beyond the lifetime of the handle object.
+
diff --git a/Doc/library/aepack.rst b/Doc/library/aepack.rst
new file mode 100644
index 0000000000..7eaffd8413
--- /dev/null
+++ b/Doc/library/aepack.rst
@@ -0,0 +1,92 @@
+
+:mod:`aepack` --- Conversion between Python variables and AppleEvent data containers
+====================================================================================
+
+.. module:: aepack
+ :platform: Mac
+ :synopsis: Conversion between Python variables and AppleEvent data containers.
+.. sectionauthor:: Vincent Marchetti <vincem@en.com>
+
+
+.. % \moduleauthor{Jack Jansen?}{email}
+
+The :mod:`aepack` module defines functions for converting (packing) Python
+variables to AppleEvent descriptors and back (unpacking). Within Python the
+AppleEvent descriptor is handled by Python objects of built-in type
+:class:`AEDesc`, defined in module :mod:`Carbon.AE`.
+
+The :mod:`aepack` module defines the following functions:
+
+
+.. function:: pack(x[, forcetype])
+
+ Returns an :class:`AEDesc` object containing a conversion of Python value x. If
+ *forcetype* is provided it specifies the descriptor type of the result.
+ Otherwise, a default mapping of Python types to Apple Event descriptor types is
+ used, as follows:
+
+ +-----------------+-----------------------------------+
+ | Python type | descriptor type |
+ +=================+===================================+
+ | :class:`FSSpec` | typeFSS |
+ +-----------------+-----------------------------------+
+ | :class:`FSRef` | typeFSRef |
+ +-----------------+-----------------------------------+
+ | :class:`Alias` | typeAlias |
+ +-----------------+-----------------------------------+
+ | integer | typeLong (32 bit integer) |
+ +-----------------+-----------------------------------+
+ | float | typeFloat (64 bit floating point) |
+ +-----------------+-----------------------------------+
+ | string | typeText |
+ +-----------------+-----------------------------------+
+ | unicode | typeUnicodeText |
+ +-----------------+-----------------------------------+
+ | list | typeAEList |
+ +-----------------+-----------------------------------+
+ | dictionary | typeAERecord |
+ +-----------------+-----------------------------------+
+ | instance | *see below* |
+ +-----------------+-----------------------------------+
+
+ If *x* is a Python instance then this function attempts to call an
+ :meth:`__aepack__` method. This method should return an :class:`AEDesc` object.
+
+ If the conversion *x* is not defined above, this function returns the Python
+ string representation of a value (the repr() function) encoded as a text
+ descriptor.
+
+
+.. function:: unpack(x[, formodulename])
+
+ *x* must be an object of type :class:`AEDesc`. This function returns a Python
+ object representation of the data in the Apple Event descriptor *x*. Simple
+ AppleEvent data types (integer, text, float) are returned as their obvious
+ Python counterparts. Apple Event lists are returned as Python lists, and the
+ list elements are recursively unpacked. Object references (ex. ``line 3 of
+ document 1``) are returned as instances of :class:`aetypes.ObjectSpecifier`,
+ unless ``formodulename`` is specified. AppleEvent descriptors with descriptor
+ type typeFSS are returned as :class:`FSSpec` objects. AppleEvent record
+ descriptors are returned as Python dictionaries, with 4-character string keys
+ and elements recursively unpacked.
+
+ The optional ``formodulename`` argument is used by the stub packages generated
+ by :mod:`gensuitemodule`, and ensures that the OSA classes for object specifiers
+ are looked up in the correct module. This ensures that if, say, the Finder
+ returns an object specifier for a window you get an instance of
+ ``Finder.Window`` and not a generic ``aetypes.Window``. The former knows about
+ all the properties and elements a window has in the Finder, while the latter
+ knows no such things.
+
+
+.. seealso::
+
+ Module :mod:`Carbon.AE`
+ Built-in access to Apple Event Manager routines.
+
+ Module :mod:`aetypes`
+ Python definitions of codes for Apple Event descriptor types.
+
+ ` Inside Macintosh: Interapplication Communication <http://developer.apple.com/techpubs/mac/IAC/IAC-2.html>`_
+ Information about inter-process communications on the Macintosh.
+
diff --git a/Doc/library/aetools.rst b/Doc/library/aetools.rst
new file mode 100644
index 0000000000..b5fd4add04
--- /dev/null
+++ b/Doc/library/aetools.rst
@@ -0,0 +1,86 @@
+
+:mod:`aetools` --- OSA client support
+=====================================
+
+.. module:: aetools
+ :platform: Mac
+ :synopsis: Basic support for sending Apple Events
+.. sectionauthor:: Jack Jansen <Jack.Jansen@cwi.nl>
+
+
+.. % \moduleauthor{Jack Jansen?}{email}
+
+The :mod:`aetools` module contains the basic functionality on which Python
+AppleScript client support is built. It also imports and re-exports the core
+functionality of the :mod:`aetypes` and :mod:`aepack` modules. The stub packages
+generated by :mod:`gensuitemodule` import the relevant portions of
+:mod:`aetools`, so usually you do not need to import it yourself. The exception
+to this is when you cannot use a generated suite package and need lower-level
+access to scripting.
+
+The :mod:`aetools` module itself uses the AppleEvent support provided by the
+:mod:`Carbon.AE` module. This has one drawback: you need access to the window
+manager, see section :ref:`osx-gui-scripts` for details. This restriction may be
+lifted in future releases.
+
+The :mod:`aetools` module defines the following functions:
+
+
+.. function:: packevent(ae, parameters, attributes)
+
+ Stores parameters and attributes in a pre-created ``Carbon.AE.AEDesc`` object.
+ ``parameters`` and ``attributes`` are dictionaries mapping 4-character OSA
+ parameter keys to Python objects. The objects are packed using
+ ``aepack.pack()``.
+
+
+.. function:: unpackevent(ae[, formodulename])
+
+ Recursively unpacks a ``Carbon.AE.AEDesc`` event to Python objects. The function
+ returns the parameter dictionary and the attribute dictionary. The
+ ``formodulename`` argument is used by generated stub packages to control where
+ AppleScript classes are looked up.
+
+
+.. function:: keysubst(arguments, keydict)
+
+ Converts a Python keyword argument dictionary ``arguments`` to the format
+ required by ``packevent`` by replacing the keys, which are Python identifiers,
+ by the four-character OSA keys according to the mapping specified in
+ ``keydict``. Used by the generated suite packages.
+
+
+.. function:: enumsubst(arguments, key, edict)
+
+ If the ``arguments`` dictionary contains an entry for ``key`` convert the value
+ for that entry according to dictionary ``edict``. This converts human-readable
+ Python enumeration names to the OSA 4-character codes. Used by the generated
+ suite packages.
+
+The :mod:`aetools` module defines the following class:
+
+
+.. class:: TalkTo([signature=None, start=0, timeout=0])
+
+ Base class for the proxy used to talk to an application. ``signature`` overrides
+ the class attribute ``_signature`` (which is usually set by subclasses) and is
+ the 4-char creator code defining the application to talk to. ``start`` can be
+ set to true to enable running the application on class instantiation.
+ ``timeout`` can be specified to change the default timeout used while waiting
+ for an AppleEvent reply.
+
+
+.. method:: TalkTo._start()
+
+ Test whether the application is running, and attempt to start it if not.
+
+
+.. method:: TalkTo.send(code, subcode[, parameters, attributes])
+
+ Create the AppleEvent ``Carbon.AE.AEDesc`` for the verb with the OSA designation
+ ``code, subcode`` (which are the usual 4-character strings), pack the
+ ``parameters`` and ``attributes`` into it, send it to the target application,
+ wait for the reply, unpack the reply with ``unpackevent`` and return the reply
+ appleevent, the unpacked return values as a dictionary and the return
+ attributes.
+
diff --git a/Doc/library/aetypes.rst b/Doc/library/aetypes.rst
new file mode 100644
index 0000000000..0dd0a88c85
--- /dev/null
+++ b/Doc/library/aetypes.rst
@@ -0,0 +1,150 @@
+
+:mod:`aetypes` --- AppleEvent objects
+=====================================
+
+.. module:: aetypes
+ :platform: Mac
+ :synopsis: Python representation of the Apple Event Object Model.
+.. sectionauthor:: Vincent Marchetti <vincem@en.com>
+
+
+.. % \moduleauthor{Jack Jansen?}{email}
+
+The :mod:`aetypes` defines classes used to represent Apple Event data
+descriptors and Apple Event object specifiers.
+
+Apple Event data is contained in descriptors, and these descriptors are typed.
+For many descriptors the Python representation is simply the corresponding
+Python type: ``typeText`` in OSA is a Python string, ``typeFloat`` is a float,
+etc. For OSA types that have no direct Python counterpart this module declares
+classes. Packing and unpacking instances of these classes is handled
+automatically by :mod:`aepack`.
+
+An object specifier is essentially an address of an object implemented in a
+Apple Event server. An Apple Event specifier is used as the direct object for an
+Apple Event or as the argument of an optional parameter. The :mod:`aetypes`
+module contains the base classes for OSA classes and properties, which are used
+by the packages generated by :mod:`gensuitemodule` to populate the classes and
+properties in a given suite.
+
+For reasons of backward compatibility, and for cases where you need to script an
+application for which you have not generated the stub package this module also
+contains object specifiers for a number of common OSA classes such as
+``Document``, ``Window``, ``Character``, etc.
+
+The :mod:`AEObjects` module defines the following classes to represent Apple
+Event descriptor data:
+
+
+.. class:: Unknown(type, data)
+
+ The representation of OSA descriptor data for which the :mod:`aepack` and
+ :mod:`aetypes` modules have no support, i.e. anything that is not represented by
+ the other classes here and that is not equivalent to a simple Python value.
+
+
+.. class:: Enum(enum)
+
+ An enumeration value with the given 4-character string value.
+
+
+.. class:: InsertionLoc(of, pos)
+
+ Position ``pos`` in object ``of``.
+
+
+.. class:: Boolean(bool)
+
+ A boolean.
+
+
+.. class:: StyledText(style, text)
+
+ Text with style information (font, face, etc) included.
+
+
+.. class:: AEText(script, style, text)
+
+ Text with script system and style information included.
+
+
+.. class:: IntlText(script, language, text)
+
+ Text with script system and language information included.
+
+
+.. class:: IntlWritingCode(script, language)
+
+ Script system and language information.
+
+
+.. class:: QDPoint(v, h)
+
+ A quickdraw point.
+
+
+.. class:: QDRectangle(v0, h0, v1, h1)
+
+ A quickdraw rectangle.
+
+
+.. class:: RGBColor(r, g, b)
+
+ A color.
+
+
+.. class:: Type(type)
+
+ An OSA type value with the given 4-character name.
+
+
+.. class:: Keyword(name)
+
+ An OSA keyword with the given 4-character name.
+
+
+.. class:: Range(start, stop)
+
+ A range.
+
+
+.. class:: Ordinal(abso)
+
+ Non-numeric absolute positions, such as ``"firs"``, first, or ``"midd"``,
+ middle.
+
+
+.. class:: Logical(logc, term)
+
+ The logical expression of applying operator ``logc`` to ``term``.
+
+
+.. class:: Comparison(obj1, relo, obj2)
+
+ The comparison ``relo`` of ``obj1`` to ``obj2``.
+
+The following classes are used as base classes by the generated stub packages to
+represent AppleScript classes and properties in Python:
+
+
+.. class:: ComponentItem(which[, fr])
+
+ Abstract baseclass for an OSA class. The subclass should set the class attribute
+ ``want`` to the 4-character OSA class code. Instances of subclasses of this
+ class are equivalent to AppleScript Object Specifiers. Upon instantiation you
+ should pass a selector in ``which``, and optionally a parent object in ``fr``.
+
+
+.. class:: NProperty(fr)
+
+ Abstract baseclass for an OSA property. The subclass should set the class
+ attributes ``want`` and ``which`` to designate which property we are talking
+ about. Instances of subclasses of this class are Object Specifiers.
+
+
+.. class:: ObjectSpecifier(want, form, seld[, fr])
+
+ Base class of ``ComponentItem`` and ``NProperty``, a general OSA Object
+ Specifier. See the Apple Open Scripting Architecture documentation for the
+ parameters. Note that this class is not abstract.
+
diff --git a/Doc/library/aifc.rst b/Doc/library/aifc.rst
new file mode 100644
index 0000000000..0cfcb52cec
--- /dev/null
+++ b/Doc/library/aifc.rst
@@ -0,0 +1,225 @@
+
+:mod:`aifc` --- Read and write AIFF and AIFC files
+==================================================
+
+.. module:: aifc
+ :synopsis: Read and write audio files in AIFF or AIFC format.
+
+
+.. index::
+ single: Audio Interchange File Format
+ single: AIFF
+ single: AIFF-C
+
+This module provides support for reading and writing AIFF and AIFF-C files.
+AIFF is Audio Interchange File Format, a format for storing digital audio
+samples in a file. AIFF-C is a newer version of the format that includes the
+ability to compress the audio data.
+
+**Caveat:** Some operations may only work under IRIX; these will raise
+:exc:`ImportError` when attempting to import the :mod:`cl` module, which is only
+available on IRIX.
+
+Audio files have a number of parameters that describe the audio data. The
+sampling rate or frame rate is the number of times per second the sound is
+sampled. The number of channels indicate if the audio is mono, stereo, or
+quadro. Each frame consists of one sample per channel. The sample size is the
+size in bytes of each sample. Thus a frame consists of
+*nchannels*\**samplesize* bytes, and a second's worth of audio consists of
+*nchannels*\**samplesize*\**framerate* bytes.
+
+For example, CD quality audio has a sample size of two bytes (16 bits), uses two
+channels (stereo) and has a frame rate of 44,100 frames/second. This gives a
+frame size of 4 bytes (2\*2), and a second's worth occupies 2\*2\*44100 bytes
+(176,400 bytes).
+
+Module :mod:`aifc` defines the following function:
+
+
+.. function:: open(file[, mode])
+
+ Open an AIFF or AIFF-C file and return an object instance with methods that are
+ described below. The argument *file* is either a string naming a file or a file
+ object. *mode* must be ``'r'`` or ``'rb'`` when the file must be opened for
+ reading, or ``'w'`` or ``'wb'`` when the file must be opened for writing. If
+ omitted, ``file.mode`` is used if it exists, otherwise ``'rb'`` is used. When
+ used for writing, the file object should be seekable, unless you know ahead of
+ time how many samples you are going to write in total and use
+ :meth:`writeframesraw` and :meth:`setnframes`.
+
+Objects returned by :func:`open` when a file is opened for reading have the
+following methods:
+
+
+.. method:: aifc.getnchannels()
+
+ Return the number of audio channels (1 for mono, 2 for stereo).
+
+
+.. method:: aifc.getsampwidth()
+
+ Return the size in bytes of individual samples.
+
+
+.. method:: aifc.getframerate()
+
+ Return the sampling rate (number of audio frames per second).
+
+
+.. method:: aifc.getnframes()
+
+ Return the number of audio frames in the file.
+
+
+.. method:: aifc.getcomptype()
+
+ Return a four-character string describing the type of compression used in the
+ audio file. For AIFF files, the returned value is ``'NONE'``.
+
+
+.. method:: aifc.getcompname()
+
+ Return a human-readable description of the type of compression used in the audio
+ file. For AIFF files, the returned value is ``'not compressed'``.
+
+
+.. method:: aifc.getparams()
+
+ Return a tuple consisting of all of the above values in the above order.
+
+
+.. method:: aifc.getmarkers()
+
+ Return a list of markers in the audio file. A marker consists of a tuple of
+ three elements. The first is the mark ID (an integer), the second is the mark
+ position in frames from the beginning of the data (an integer), the third is the
+ name of the mark (a string).
+
+
+.. method:: aifc.getmark(id)
+
+ Return the tuple as described in :meth:`getmarkers` for the mark with the given
+ *id*.
+
+
+.. method:: aifc.readframes(nframes)
+
+ Read and return the next *nframes* frames from the audio file. The returned
+ data is a string containing for each frame the uncompressed samples of all
+ channels.
+
+
+.. method:: aifc.rewind()
+
+ Rewind the read pointer. The next :meth:`readframes` will start from the
+ beginning.
+
+
+.. method:: aifc.setpos(pos)
+
+ Seek to the specified frame number.
+
+
+.. method:: aifc.tell()
+
+ Return the current frame number.
+
+
+.. method:: aifc.close()
+
+ Close the AIFF file. After calling this method, the object can no longer be
+ used.
+
+Objects returned by :func:`open` when a file is opened for writing have all the
+above methods, except for :meth:`readframes` and :meth:`setpos`. In addition
+the following methods exist. The :meth:`get\*` methods can only be called after
+the corresponding :meth:`set\*` methods have been called. Before the first
+:meth:`writeframes` or :meth:`writeframesraw`, all parameters except for the
+number of frames must be filled in.
+
+
+.. method:: aifc.aiff()
+
+ Create an AIFF file. The default is that an AIFF-C file is created, unless the
+ name of the file ends in ``'.aiff'`` in which case the default is an AIFF file.
+
+
+.. method:: aifc.aifc()
+
+ Create an AIFF-C file. The default is that an AIFF-C file is created, unless
+ the name of the file ends in ``'.aiff'`` in which case the default is an AIFF
+ file.
+
+
+.. method:: aifc.setnchannels(nchannels)
+
+ Specify the number of channels in the audio file.
+
+
+.. method:: aifc.setsampwidth(width)
+
+ Specify the size in bytes of audio samples.
+
+
+.. method:: aifc.setframerate(rate)
+
+ Specify the sampling frequency in frames per second.
+
+
+.. method:: aifc.setnframes(nframes)
+
+ Specify the number of frames that are to be written to the audio file. If this
+ parameter is not set, or not set correctly, the file needs to support seeking.
+
+
+.. method:: aifc.setcomptype(type, name)
+
+ .. index::
+ single: u-LAW
+ single: A-LAW
+ single: G.722
+
+ Specify the compression type. If not specified, the audio data will not be
+ compressed. In AIFF files, compression is not possible. The name parameter
+ should be a human-readable description of the compression type, the type
+ parameter should be a four-character string. Currently the following
+ compression types are supported: NONE, ULAW, ALAW, G722.
+
+
+.. method:: aifc.setparams(nchannels, sampwidth, framerate, comptype, compname)
+
+ Set all the above parameters at once. The argument is a tuple consisting of the
+ various parameters. This means that it is possible to use the result of a
+ :meth:`getparams` call as argument to :meth:`setparams`.
+
+
+.. method:: aifc.setmark(id, pos, name)
+
+ Add a mark with the given id (larger than 0), and the given name at the given
+ position. This method can be called at any time before :meth:`close`.
+
+
+.. method:: aifc.tell()
+
+ Return the current write position in the output file. Useful in combination
+ with :meth:`setmark`.
+
+
+.. method:: aifc.writeframes(data)
+
+ Write data to the output file. This method can only be called after the audio
+ file parameters have been set.
+
+
+.. method:: aifc.writeframesraw(data)
+
+ Like :meth:`writeframes`, except that the header of the audio file is not
+ updated.
+
+
+.. method:: aifc.close()
+
+ Close the AIFF file. The header of the file is updated to reflect the actual
+ size of the audio data. After calling this method, the object can no longer be
+ used.
+
diff --git a/Doc/library/allos.rst b/Doc/library/allos.rst
new file mode 100644
index 0000000000..900d6d3cec
--- /dev/null
+++ b/Doc/library/allos.rst
@@ -0,0 +1,27 @@
+
+.. _allos:
+
+*********************************
+Generic Operating System Services
+*********************************
+
+The modules described in this chapter provide interfaces to operating system
+features that are available on (almost) all operating systems, such as files and
+a clock. The interfaces are generally modeled after the Unix or C interfaces,
+but they are available on most other systems as well. Here's an overview:
+
+
+.. toctree::
+
+ os.rst
+ time.rst
+ optparse.rst
+ getopt.rst
+ logging.rst
+ getpass.rst
+ curses.rst
+ curses.ascii.rst
+ curses.panel.rst
+ platform.rst
+ errno.rst
+ ctypes.rst
diff --git a/Doc/library/anydbm.rst b/Doc/library/anydbm.rst
new file mode 100644
index 0000000000..413b7de9a7
--- /dev/null
+++ b/Doc/library/anydbm.rst
@@ -0,0 +1,96 @@
+
+:mod:`anydbm` --- Generic access to DBM-style databases
+=======================================================
+
+.. module:: anydbm
+ :synopsis: Generic interface to DBM-style database modules.
+
+
+.. index::
+ module: dbhash
+ module: bsddb
+ module: gdbm
+ module: dbm
+ module: dumbdbm
+
+:mod:`anydbm` is a generic interface to variants of the DBM database ---
+:mod:`dbhash` (requires :mod:`bsddb`), :mod:`gdbm`, or :mod:`dbm`. If none of
+these modules is installed, the slow-but-simple implementation in module
+:mod:`dumbdbm` will be used.
+
+
+.. function:: open(filename[, flag[, mode]])
+
+ Open the database file *filename* and return a corresponding object.
+
+ If the database file already exists, the :mod:`whichdb` module is used to
+ determine its type and the appropriate module is used; if it does not exist, the
+ first module listed above that can be imported is used.
+
+ The optional *flag* argument can be ``'r'`` to open an existing database for
+ reading only, ``'w'`` to open an existing database for reading and writing,
+ ``'c'`` to create the database if it doesn't exist, or ``'n'``, which will
+ always create a new empty database. If not specified, the default value is
+ ``'r'``.
+
+ The optional *mode* argument is the Unix mode of the file, used only when the
+ database has to be created. It defaults to octal ``0666`` (and will be modified
+ by the prevailing umask).
+
+
+.. exception:: error
+
+ A tuple containing the exceptions that can be raised by each of the supported
+ modules, with a unique exception also named :exc:`anydbm.error` as the first
+ item --- the latter is used when :exc:`anydbm.error` is raised.
+
+The object returned by :func:`open` supports most of the same functionality as
+dictionaries; keys and their corresponding values can be stored, retrieved, and
+deleted, and the :meth:`has_key` and :meth:`keys` methods are available. Keys
+and values must always be strings.
+
+The following example records some hostnames and a corresponding title, and
+then prints out the contents of the database::
+
+ import anydbm
+
+ # Open database, creating it if necessary.
+ db = anydbm.open('cache', 'c')
+
+ # Record some values
+ db['www.python.org'] = 'Python Website'
+ db['www.cnn.com'] = 'Cable News Network'
+
+ # Loop through contents. Other dictionary methods
+ # such as .keys(), .values() also work.
+ for k, v in db.iteritems():
+ print k, '\t', v
+
+ # Storing a non-string key or value will raise an exception (most
+ # likely a TypeError).
+ db['www.yahoo.com'] = 4
+
+ # Close when done.
+ db.close()
+
+
+.. seealso::
+
+ Module :mod:`dbhash`
+ BSD ``db`` database interface.
+
+ Module :mod:`dbm`
+ Standard Unix database interface.
+
+ Module :mod:`dumbdbm`
+ Portable implementation of the ``dbm`` interface.
+
+ Module :mod:`gdbm`
+ GNU database interface, based on the ``dbm`` interface.
+
+ Module :mod:`shelve`
+ General object persistence built on top of the Python ``dbm`` interface.
+
+ Module :mod:`whichdb`
+ Utility module used to determine the type of an existing database.
+
diff --git a/Doc/library/archiving.rst b/Doc/library/archiving.rst
new file mode 100644
index 0000000000..7d0df5f575
--- /dev/null
+++ b/Doc/library/archiving.rst
@@ -0,0 +1,18 @@
+
+.. _archiving:
+
+******************************
+Data Compression and Archiving
+******************************
+
+The modules described in this chapter support data compression with the zlib,
+gzip, and bzip2 algorithms, and the creation of ZIP- and tar-format archives.
+
+
+.. toctree::
+
+ zlib.rst
+ gzip.rst
+ bz2.rst
+ zipfile.rst
+ tarfile.rst
diff --git a/Doc/library/array.rst b/Doc/library/array.rst
new file mode 100644
index 0000000000..5194edc4e0
--- /dev/null
+++ b/Doc/library/array.rst
@@ -0,0 +1,272 @@
+
+:mod:`array` --- Efficient arrays of numeric values
+===================================================
+
+.. module:: array
+ :synopsis: Efficient arrays of uniformly typed numeric values.
+
+
+.. index:: single: arrays
+
+This module defines an object type which can efficiently represent an array of
+basic values: characters, integers, floating point numbers. Arrays are sequence
+types and behave very much like lists, except that the type of objects stored in
+them is constrained. The type is specified at object creation time by using a
+:dfn:`type code`, which is a single character. The following type codes are
+defined:
+
++-----------+----------------+-------------------+-----------------------+
+| Type code | C Type | Python Type | Minimum size in bytes |
++===========+================+===================+=======================+
+| ``'c'`` | char | character | 1 |
++-----------+----------------+-------------------+-----------------------+
+| ``'b'`` | signed char | int | 1 |
++-----------+----------------+-------------------+-----------------------+
+| ``'B'`` | unsigned char | int | 1 |
++-----------+----------------+-------------------+-----------------------+
+| ``'u'`` | Py_UNICODE | Unicode character | 2 |
++-----------+----------------+-------------------+-----------------------+
+| ``'h'`` | signed short | int | 2 |
++-----------+----------------+-------------------+-----------------------+
+| ``'H'`` | unsigned short | int | 2 |
++-----------+----------------+-------------------+-----------------------+
+| ``'i'`` | signed int | int | 2 |
++-----------+----------------+-------------------+-----------------------+
+| ``'I'`` | unsigned int | long | 2 |
++-----------+----------------+-------------------+-----------------------+
+| ``'l'`` | signed long | int | 4 |
++-----------+----------------+-------------------+-----------------------+
+| ``'L'`` | unsigned long | long | 4 |
++-----------+----------------+-------------------+-----------------------+
+| ``'f'`` | float | float | 4 |
++-----------+----------------+-------------------+-----------------------+
+| ``'d'`` | double | float | 8 |
++-----------+----------------+-------------------+-----------------------+
+
+The actual representation of values is determined by the machine architecture
+(strictly speaking, by the C implementation). The actual size can be accessed
+through the :attr:`itemsize` attribute. The values stored for ``'L'`` and
+``'I'`` items will be represented as Python long integers when retrieved,
+because Python's plain integer type cannot represent the full range of C's
+unsigned (long) integers.
+
+The module defines the following type:
+
+
+.. function:: array(typecode[, initializer])
+
+ Return a new array whose items are restricted by *typecode*, and initialized
+ from the optional *initializer* value, which must be a list, string, or iterable
+ over elements of the appropriate type.
+
+ .. versionchanged:: 2.4
+ Formerly, only lists or strings were accepted.
+
+ If given a list or string, the initializer is passed to the new array's
+ :meth:`fromlist`, :meth:`fromstring`, or :meth:`fromunicode` method (see below)
+ to add initial items to the array. Otherwise, the iterable initializer is
+ passed to the :meth:`extend` method.
+
+
+.. data:: ArrayType
+
+ Obsolete alias for :func:`array`.
+
+Array objects support the ordinary sequence operations of indexing, slicing,
+concatenation, and multiplication. When using slice assignment, the assigned
+value must be an array object with the same type code; in all other cases,
+:exc:`TypeError` is raised. Array objects also implement the buffer interface,
+and may be used wherever buffer objects are supported.
+
+The following data items and methods are also supported:
+
+
+.. attribute:: array.typecode
+
+ The typecode character used to create the array.
+
+
+.. attribute:: array.itemsize
+
+ The length in bytes of one array item in the internal representation.
+
+
+.. method:: array.append(x)
+
+ Append a new item with value *x* to the end of the array.
+
+
+.. method:: array.buffer_info()
+
+ Return a tuple ``(address, length)`` giving the current memory address and the
+ length in elements of the buffer used to hold array's contents. The size of the
+ memory buffer in bytes can be computed as ``array.buffer_info()[1] *
+ array.itemsize``. This is occasionally useful when working with low-level (and
+ inherently unsafe) I/O interfaces that require memory addresses, such as certain
+ :cfunc:`ioctl` operations. The returned numbers are valid as long as the array
+ exists and no length-changing operations are applied to it.
+
+ .. note::
+
+ When using array objects from code written in C or C++ (the only way to
+ effectively make use of this information), it makes more sense to use the buffer
+ interface supported by array objects. This method is maintained for backward
+ compatibility and should be avoided in new code. The buffer interface is
+ documented in :ref:`bufferobjects`.
+
+
+.. method:: array.byteswap()
+
+ "Byteswap" all items of the array. This is only supported for values which are
+ 1, 2, 4, or 8 bytes in size; for other types of values, :exc:`RuntimeError` is
+ raised. It is useful when reading data from a file written on a machine with a
+ different byte order.
+
+
+.. method:: array.count(x)
+
+ Return the number of occurrences of *x* in the array.
+
+
+.. method:: array.extend(iterable)
+
+ Append items from *iterable* to the end of the array. If *iterable* is another
+ array, it must have *exactly* the same type code; if not, :exc:`TypeError` will
+ be raised. If *iterable* is not an array, it must be iterable and its elements
+ must be the right type to be appended to the array.
+
+ .. versionchanged:: 2.4
+ Formerly, the argument could only be another array.
+
+
+.. method:: array.fromfile(f, n)
+
+ Read *n* items (as machine values) from the file object *f* and append them to
+ the end of the array. If less than *n* items are available, :exc:`EOFError` is
+ raised, but the items that were available are still inserted into the array.
+ *f* must be a real built-in file object; something else with a :meth:`read`
+ method won't do.
+
+
+.. method:: array.fromlist(list)
+
+ Append items from the list. This is equivalent to ``for x in list:
+ a.append(x)`` except that if there is a type error, the array is unchanged.
+
+
+.. method:: array.fromstring(s)
+
+ Appends items from the string, interpreting the string as an array of machine
+ values (as if it had been read from a file using the :meth:`fromfile` method).
+
+
+.. method:: array.fromunicode(s)
+
+ Extends this array with data from the given unicode string. The array must
+ be a type ``'u'`` array; otherwise a :exc:`ValueError` is raised. Use
+ ``array.fromstring(unicodestring.encode(enc))`` to append Unicode data to an
+ array of some other type.
+
+
+.. method:: array.index(x)
+
+ Return the smallest *i* such that *i* is the index of the first occurrence of
+ *x* in the array.
+
+
+.. method:: array.insert(i, x)
+
+ Insert a new item with value *x* in the array before position *i*. Negative
+ values are treated as being relative to the end of the array.
+
+
+.. method:: array.pop([i])
+
+ Removes the item with the index *i* from the array and returns it. The optional
+ argument defaults to ``-1``, so that by default the last item is removed and
+ returned.
+
+
+.. method:: array.read(f, n)
+
+ .. deprecated:: 1.5.1
+ Use the :meth:`fromfile` method.
+
+ Read *n* items (as machine values) from the file object *f* and append them to
+ the end of the array. If less than *n* items are available, :exc:`EOFError` is
+ raised, but the items that were available are still inserted into the array.
+ *f* must be a real built-in file object; something else with a :meth:`read`
+ method won't do.
+
+
+.. method:: array.remove(x)
+
+ Remove the first occurrence of *x* from the array.
+
+
+.. method:: array.reverse()
+
+ Reverse the order of the items in the array.
+
+
+.. method:: array.tofile(f)
+
+ Write all items (as machine values) to the file object *f*.
+
+
+.. method:: array.tolist()
+
+ Convert the array to an ordinary list with the same items.
+
+
+.. method:: array.tostring()
+
+ Convert the array to an array of machine values and return the string
+ representation (the same sequence of bytes that would be written to a file by
+ the :meth:`tofile` method.)
+
+
+.. method:: array.tounicode()
+
+ Convert the array to a unicode string. The array must be a type ``'u'`` array;
+ otherwise a :exc:`ValueError` is raised. Use ``array.tostring().decode(enc)`` to
+ obtain a unicode string from an array of some other type.
+
+
+.. method:: array.write(f)
+
+ .. deprecated:: 1.5.1
+ Use the :meth:`tofile` method.
+
+ Write all items (as machine values) to the file object *f*.
+
+When an array object is printed or converted to a string, it is represented as
+``array(typecode, initializer)``. The *initializer* is omitted if the array is
+empty, otherwise it is a string if the *typecode* is ``'c'``, otherwise it is a
+list of numbers. The string is guaranteed to be able to be converted back to an
+array with the same type and value using :func:`eval`, so long as the
+:func:`array` function has been imported using ``from array import array``.
+Examples::
+
+ array('l')
+ array('c', 'hello world')
+ array('u', u'hello \u2641')
+ array('l', [1, 2, 3, 4, 5])
+ array('d', [1.0, 2.0, 3.14])
+
+
+.. seealso::
+
+ Module :mod:`struct`
+ Packing and unpacking of heterogeneous binary data.
+
+ Module :mod:`xdrlib`
+ Packing and unpacking of External Data Representation (XDR) data as used in some
+ remote procedure call systems.
+
+ `The Numerical Python Manual <http://numpy.sourceforge.net/numdoc/HTML/numdoc.htm>`_
+ The Numeric Python extension (NumPy) defines another array type; see
+ http://numpy.sourceforge.net/ for further information about Numerical Python.
+ (A PDF version of the NumPy manual is available at
+ http://numpy.sourceforge.net/numdoc/numdoc.pdf).
+
diff --git a/Doc/library/asynchat.rst b/Doc/library/asynchat.rst
new file mode 100644
index 0000000000..b651c40399
--- /dev/null
+++ b/Doc/library/asynchat.rst
@@ -0,0 +1,284 @@
+
+:mod:`asynchat` --- Asynchronous socket command/response handler
+================================================================
+
+.. module:: asynchat
+ :synopsis: Support for asynchronous command/response protocols.
+.. moduleauthor:: Sam Rushing <rushing@nightmare.com>
+.. sectionauthor:: Steve Holden <sholden@holdenweb.com>
+
+
+This module builds on the :mod:`asyncore` infrastructure, simplifying
+asynchronous clients and servers and making it easier to handle protocols whose
+elements are terminated by arbitrary strings, or are of variable length.
+:mod:`asynchat` defines the abstract class :class:`async_chat` that you
+subclass, providing implementations of the :meth:`collect_incoming_data` and
+:meth:`found_terminator` methods. It uses the same asynchronous loop as
+:mod:`asyncore`, and the two types of channel, :class:`asyncore.dispatcher` and
+:class:`asynchat.async_chat`, can freely be mixed in the channel map. Typically
+an :class:`asyncore.dispatcher` server channel generates new
+:class:`asynchat.async_chat` channel objects as it receives incoming connection
+requests.
+
+
+.. class:: async_chat()
+
+ This class is an abstract subclass of :class:`asyncore.dispatcher`. To make
+ practical use of the code you must subclass :class:`async_chat`, providing
+ meaningful :meth:`collect_incoming_data` and :meth:`found_terminator` methods.
+ The :class:`asyncore.dispatcher` methods can be used, although not all make
+ sense in a message/response context.
+
+ Like :class:`asyncore.dispatcher`, :class:`async_chat` defines a set of events
+ that are generated by an analysis of socket conditions after a :cfunc:`select`
+ call. Once the polling loop has been started the :class:`async_chat` object's
+ methods are called by the event-processing framework with no action on the part
+ of the programmer.
+
+ Unlike :class:`asyncore.dispatcher`, :class:`async_chat` allows you to define a
+ first-in-first-out queue (fifo) of *producers*. A producer need have only one
+ method, :meth:`more`, which should return data to be transmitted on the channel.
+ The producer indicates exhaustion (*i.e.* that it contains no more data) by
+ having its :meth:`more` method return the empty string. At this point the
+ :class:`async_chat` object removes the producer from the fifo and starts using
+ the next producer, if any. When the producer fifo is empty the
+ :meth:`handle_write` method does nothing. You use the channel object's
+ :meth:`set_terminator` method to describe how to recognize the end of, or an
+ important breakpoint in, an incoming transmission from the remote endpoint.
+
+ To build a functioning :class:`async_chat` subclass your input methods
+ :meth:`collect_incoming_data` and :meth:`found_terminator` must handle the data
+ that the channel receives asynchronously. The methods are described below.
+
+
+.. method:: async_chat.close_when_done()
+
+ Pushes a ``None`` on to the producer fifo. When this producer is popped off the
+ fifo it causes the channel to be closed.
+
+
+.. method:: async_chat.collect_incoming_data(data)
+
+ Called with *data* holding an arbitrary amount of received data. The default
+ method, which must be overridden, raises a :exc:`NotImplementedError` exception.
+
+
+.. method:: async_chat.discard_buffers()
+
+ In emergencies this method will discard any data held in the input and/or output
+ buffers and the producer fifo.
+
+
+.. method:: async_chat.found_terminator()
+
+ Called when the incoming data stream matches the termination condition set by
+ :meth:`set_terminator`. The default method, which must be overridden, raises a
+ :exc:`NotImplementedError` exception. The buffered input data should be
+ available via an instance attribute.
+
+
+.. method:: async_chat.get_terminator()
+
+ Returns the current terminator for the channel.
+
+
+.. method:: async_chat.handle_close()
+
+ Called when the channel is closed. The default method silently closes the
+ channel's socket.
+
+
+.. method:: async_chat.handle_read()
+
+ Called when a read event fires on the channel's socket in the asynchronous loop.
+ The default method checks for the termination condition established by
+ :meth:`set_terminator`, which can be either the appearance of a particular
+ string in the input stream or the receipt of a particular number of characters.
+ When the terminator is found, :meth:`handle_read` calls the
+ :meth:`found_terminator` method after calling :meth:`collect_incoming_data` with
+ any data preceding the terminating condition.
+
+
+.. method:: async_chat.handle_write()
+
+ Called when the application may write data to the channel. The default method
+ calls the :meth:`initiate_send` method, which in turn will call
+ :meth:`refill_buffer` to collect data from the producer fifo associated with the
+ channel.
+
+
+.. method:: async_chat.push(data)
+
+ Creates a :class:`simple_producer` object (*see below*) containing the data and
+ pushes it on to the channel's ``producer_fifo`` to ensure its transmission. This
+ is all you need to do to have the channel write the data out to the network,
+ although it is possible to use your own producers in more complex schemes to
+ implement encryption and chunking, for example.
+
+
+.. method:: async_chat.push_with_producer(producer)
+
+ Takes a producer object and adds it to the producer fifo associated with the
+ channel. When all currently-pushed producers have been exhausted the channel
+ will consume this producer's data by calling its :meth:`more` method and send
+ the data to the remote endpoint.
+
+
+.. method:: async_chat.readable()
+
+ Should return ``True`` for the channel to be included in the set of channels
+ tested by the :cfunc:`select` loop for readability.
+
+
+.. method:: async_chat.refill_buffer()
+
+ Refills the output buffer by calling the :meth:`more` method of the producer at
+ the head of the fifo. If it is exhausted then the producer is popped off the
+ fifo and the next producer is activated. If the current producer is, or becomes,
+ ``None`` then the channel is closed.
+
+
+.. method:: async_chat.set_terminator(term)
+
+ Sets the terminating condition to be recognised on the channel. ``term`` may be
+ any of three types of value, corresponding to three different ways to handle
+ incoming protocol data.
+
+ +-----------+---------------------------------------------+
+ | term | Description |
+ +===========+=============================================+
+ | *string* | Will call :meth:`found_terminator` when the |
+ | | string is found in the input stream |
+ +-----------+---------------------------------------------+
+ | *integer* | Will call :meth:`found_terminator` when the |
+ | | indicated number of characters have been |
+ | | received |
+ +-----------+---------------------------------------------+
+ | ``None`` | The channel continues to collect data |
+ | | forever |
+ +-----------+---------------------------------------------+
+
+ Note that any data following the terminator will be available for reading by the
+ channel after :meth:`found_terminator` is called.
+
+
+.. method:: async_chat.writable()
+
+ Should return ``True`` as long as items remain on the producer fifo, or the
+ channel is connected and the channel's output buffer is non-empty.
+
+
+asynchat - Auxiliary Classes and Functions
+------------------------------------------
+
+
+.. class:: simple_producer(data[, buffer_size=512])
+
+ A :class:`simple_producer` takes a chunk of data and an optional buffer size.
+ Repeated calls to its :meth:`more` method yield successive chunks of the data no
+ larger than *buffer_size*.
+
+
+.. method:: simple_producer.more()
+
+ Produces the next chunk of information from the producer, or returns the empty
+ string.
+
+
+.. class:: fifo([list=None])
+
+ Each channel maintains a :class:`fifo` holding data which has been pushed by the
+ application but not yet popped for writing to the channel. A :class:`fifo` is a
+ list used to hold data and/or producers until they are required. If the *list*
+ argument is provided then it should contain producers or data items to be
+ written to the channel.
+
+
+.. method:: fifo.is_empty()
+
+ Returns ``True`` iff the fifo is empty.
+
+
+.. method:: fifo.first()
+
+ Returns the least-recently :meth:`push`\ ed item from the fifo.
+
+
+.. method:: fifo.push(data)
+
+ Adds the given data (which may be a string or a producer object) to the producer
+ fifo.
+
+
+.. method:: fifo.pop()
+
+ If the fifo is not empty, returns ``True, first()``, deleting the popped item.
+ Returns ``False, None`` for an empty fifo.
+
+The :mod:`asynchat` module also defines one utility function, which may be of
+use in network and textual analysis operations.
+
+
+.. function:: find_prefix_at_end(haystack, needle)
+
+ Returns ``True`` if string *haystack* ends with any non-empty prefix of string
+ *needle*.
+
+
+.. _asynchat-example:
+
+asynchat Example
+----------------
+
+The following partial example shows how HTTP requests can be read with
+:class:`async_chat`. A web server might create an :class:`http_request_handler`
+object for each incoming client connection. Notice that initially the channel
+terminator is set to match the blank line at the end of the HTTP headers, and a
+flag indicates that the headers are being read.
+
+Once the headers have been read, if the request is of type POST (indicating that
+further data are present in the input stream) then the ``Content-Length:``
+header is used to set a numeric terminator to read the right amount of data from
+the channel.
+
+The :meth:`handle_request` method is called once all relevant input has been
+marshalled, after setting the channel terminator to ``None`` to ensure that any
+extraneous data sent by the web client are ignored. ::
+
+ class http_request_handler(asynchat.async_chat):
+
+ def __init__(self, conn, addr, sessions, log):
+ asynchat.async_chat.__init__(self, conn=conn)
+ self.addr = addr
+ self.sessions = sessions
+ self.ibuffer = []
+ self.obuffer = ""
+ self.set_terminator("\r\n\r\n")
+ self.reading_headers = True
+ self.handling = False
+ self.cgi_data = None
+ self.log = log
+
+ def collect_incoming_data(self, data):
+ """Buffer the data"""
+ self.ibuffer.append(data)
+
+ def found_terminator(self):
+ if self.reading_headers:
+ self.reading_headers = False
+ self.parse_headers("".join(self.ibuffer))
+ self.ibuffer = []
+ if self.op.upper() == "POST":
+ clen = self.headers.getheader("content-length")
+ self.set_terminator(int(clen))
+ else:
+ self.handling = True
+ self.set_terminator(None)
+ self.handle_request()
+ elif not self.handling:
+ self.set_terminator(None) # browsers sometimes over-send
+ self.cgi_data = parse(self.headers, "".join(self.ibuffer))
+ self.handling = True
+ self.ibuffer = []
+ self.handle_request()
+
diff --git a/Doc/library/asyncore.rst b/Doc/library/asyncore.rst
new file mode 100644
index 0000000000..7f80dd3b4b
--- /dev/null
+++ b/Doc/library/asyncore.rst
@@ -0,0 +1,269 @@
+
+:mod:`asyncore` --- Asynchronous socket handler
+===============================================
+
+.. module:: asyncore
+ :synopsis: A base class for developing asynchronous socket handling services.
+.. moduleauthor:: Sam Rushing <rushing@nightmare.com>
+.. sectionauthor:: Christopher Petrilli <petrilli@amber.org>
+.. sectionauthor:: Steve Holden <sholden@holdenweb.com>
+
+
+This module provides the basic infrastructure for writing asynchronous socket
+service clients and servers.
+
+.. % Heavily adapted from original documentation by Sam Rushing.
+
+There are only two ways to have a program on a single processor do "more than
+one thing at a time." Multi-threaded programming is the simplest and most
+popular way to do it, but there is another very different technique, that lets
+you have nearly all the advantages of multi-threading, without actually using
+multiple threads. It's really only practical if your program is largely I/O
+bound. If your program is processor bound, then pre-emptive scheduled threads
+are probably what you really need. Network servers are rarely processor bound,
+however.
+
+If your operating system supports the :cfunc:`select` system call in its I/O
+library (and nearly all do), then you can use it to juggle multiple
+communication channels at once; doing other work while your I/O is taking place
+in the "background." Although this strategy can seem strange and complex,
+especially at first, it is in many ways easier to understand and control than
+multi-threaded programming. The :mod:`asyncore` module solves many of the
+difficult problems for you, making the task of building sophisticated
+high-performance network servers and clients a snap. For "conversational"
+applications and protocols the companion :mod:`asynchat` module is invaluable.
+
+The basic idea behind both modules is to create one or more network *channels*,
+instances of class :class:`asyncore.dispatcher` and
+:class:`asynchat.async_chat`. Creating the channels adds them to a global map,
+used by the :func:`loop` function if you do not provide it with your own *map*.
+
+Once the initial channel(s) is(are) created, calling the :func:`loop` function
+activates channel service, which continues until the last channel (including any
+that have been added to the map during asynchronous service) is closed.
+
+
+.. function:: loop([timeout[, use_poll[, map[,count]]]])
+
+ Enter a polling loop that terminates after count passes or all open channels
+ have been closed. All arguments are optional. The *count* parameter defaults
+ to None, resulting in the loop terminating only when all channels have been
+ closed. The *timeout* argument sets the timeout parameter for the appropriate
+ :func:`select` or :func:`poll` call, measured in seconds; the default is 30
+ seconds. The *use_poll* parameter, if true, indicates that :func:`poll` should
+ be used in preference to :func:`select` (the default is ``False``).
+
+ The *map* parameter is a dictionary whose items are the channels to watch. As
+ channels are closed they are deleted from their map. If *map* is omitted, a
+ global map is used. Channels (instances of :class:`asyncore.dispatcher`,
+ :class:`asynchat.async_chat` and subclasses thereof) can freely be mixed in the
+ map.
+
+
+.. class:: dispatcher()
+
+ The :class:`dispatcher` class is a thin wrapper around a low-level socket
+ object. To make it more useful, it has a few methods for event-handling which
+ are called from the asynchronous loop. Otherwise, it can be treated as a
+ normal non-blocking socket object.
+
+ Two class attributes can be modified, to improve performance, or possibly even
+ to conserve memory.
+
+
+ .. data:: ac_in_buffer_size
+
+ The asynchronous input buffer size (default ``4096``).
+
+
+ .. data:: ac_out_buffer_size
+
+ The asynchronous output buffer size (default ``4096``).
+
+ The firing of low-level events at certain times or in certain connection states
+ tells the asynchronous loop that certain higher-level events have taken place.
+ For example, if we have asked for a socket to connect to another host, we know
+ that the connection has been made when the socket becomes writable for the first
+ time (at this point you know that you may write to it with the expectation of
+ success). The implied higher-level events are:
+
+ +----------------------+----------------------------------------+
+ | Event | Description |
+ +======================+========================================+
+ | ``handle_connect()`` | Implied by the first write event |
+ +----------------------+----------------------------------------+
+ | ``handle_close()`` | Implied by a read event with no data |
+ | | available |
+ +----------------------+----------------------------------------+
+ | ``handle_accept()`` | Implied by a read event on a listening |
+ | | socket |
+ +----------------------+----------------------------------------+
+
+ During asynchronous processing, each mapped channel's :meth:`readable` and
+ :meth:`writable` methods are used to determine whether the channel's socket
+ should be added to the list of channels :cfunc:`select`\ ed or :cfunc:`poll`\ ed
+ for read and write events.
+
+Thus, the set of channel events is larger than the basic socket events. The full
+set of methods that can be overridden in your subclass follows:
+
+
+.. method:: dispatcher.handle_read()
+
+ Called when the asynchronous loop detects that a :meth:`read` call on the
+ channel's socket will succeed.
+
+
+.. method:: dispatcher.handle_write()
+
+ Called when the asynchronous loop detects that a writable socket can be written.
+ Often this method will implement the necessary buffering for performance. For
+ example::
+
+ def handle_write(self):
+ sent = self.send(self.buffer)
+ self.buffer = self.buffer[sent:]
+
+
+.. method:: dispatcher.handle_expt()
+
+ Called when there is out of band (OOB) data for a socket connection. This will
+ almost never happen, as OOB is tenuously supported and rarely used.
+
+
+.. method:: dispatcher.handle_connect()
+
+ Called when the active opener's socket actually makes a connection. Might send a
+ "welcome" banner, or initiate a protocol negotiation with the remote endpoint,
+ for example.
+
+
+.. method:: dispatcher.handle_close()
+
+ Called when the socket is closed.
+
+
+.. method:: dispatcher.handle_error()
+
+ Called when an exception is raised and not otherwise handled. The default
+ version prints a condensed traceback.
+
+
+.. method:: dispatcher.handle_accept()
+
+ Called on listening channels (passive openers) when a connection can be
+ established with a new remote endpoint that has issued a :meth:`connect` call
+ for the local endpoint.
+
+
+.. method:: dispatcher.readable()
+
+ Called each time around the asynchronous loop to determine whether a channel's
+ socket should be added to the list on which read events can occur. The default
+ method simply returns ``True``, indicating that by default, all channels will
+ be interested in read events.
+
+
+.. method:: dispatcher.writable()
+
+ Called each time around the asynchronous loop to determine whether a channel's
+ socket should be added to the list on which write events can occur. The default
+ method simply returns ``True``, indicating that by default, all channels will
+ be interested in write events.
+
+In addition, each channel delegates or extends many of the socket methods. Most
+of these are nearly identical to their socket partners.
+
+
+.. method:: dispatcher.create_socket(family, type)
+
+ This is identical to the creation of a normal socket, and will use the same
+ options for creation. Refer to the :mod:`socket` documentation for information
+ on creating sockets.
+
+
+.. method:: dispatcher.connect(address)
+
+ As with the normal socket object, *address* is a tuple with the first element
+ the host to connect to, and the second the port number.
+
+
+.. method:: dispatcher.send(data)
+
+ Send *data* to the remote end-point of the socket.
+
+
+.. method:: dispatcher.recv(buffer_size)
+
+ Read at most *buffer_size* bytes from the socket's remote end-point. An empty
+ string implies that the channel has been closed from the other end.
+
+
+.. method:: dispatcher.listen(backlog)
+
+ Listen for connections made to the socket. The *backlog* argument specifies the
+ maximum number of queued connections and should be at least 1; the maximum value
+ is system-dependent (usually 5).
+
+
+.. method:: dispatcher.bind(address)
+
+ Bind the socket to *address*. The socket must not already be bound. (The
+ format of *address* depends on the address family --- see above.) To mark the
+ socket as re-usable (setting the :const:`SO_REUSEADDR` option), call the
+ :class:`dispatcher` object's :meth:`set_reuse_addr` method.
+
+
+.. method:: dispatcher.accept()
+
+ Accept a connection. The socket must be bound to an address and listening for
+ connections. The return value is a pair ``(conn, address)`` where *conn* is a
+ *new* socket object usable to send and receive data on the connection, and
+ *address* is the address bound to the socket on the other end of the connection.
+
+
+.. method:: dispatcher.close()
+
+ Close the socket. All future operations on the socket object will fail. The
+ remote end-point will receive no more data (after queued data is flushed).
+ Sockets are automatically closed when they are garbage-collected.
+
+
+.. _asyncore-example:
+
+asyncore Example basic HTTP client
+----------------------------------
+
+Here is a very basic HTTP client that uses the :class:`dispatcher` class to
+implement its socket handling::
+
+ import asyncore, socket
+
+ class http_client(asyncore.dispatcher):
+
+ def __init__(self, host, path):
+ asyncore.dispatcher.__init__(self)
+ self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
+ self.connect( (host, 80) )
+ self.buffer = 'GET %s HTTP/1.0\r\n\r\n' % path
+
+ def handle_connect(self):
+ pass
+
+ def handle_close(self):
+ self.close()
+
+ def handle_read(self):
+ print self.recv(8192)
+
+ def writable(self):
+ return (len(self.buffer) > 0)
+
+ def handle_write(self):
+ sent = self.send(self.buffer)
+ self.buffer = self.buffer[sent:]
+
+ c = http_client('www.python.org', '/')
+
+ asyncore.loop()
+
diff --git a/Doc/library/atexit.rst b/Doc/library/atexit.rst
new file mode 100644
index 0000000000..94d750b7c9
--- /dev/null
+++ b/Doc/library/atexit.rst
@@ -0,0 +1,105 @@
+
+:mod:`atexit` --- Exit handlers
+===============================
+
+.. module:: atexit
+ :synopsis: Register and execute cleanup functions.
+.. moduleauthor:: Skip Montanaro <skip@mojam.com>
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+.. versionadded:: 2.0
+
+The :mod:`atexit` module defines functions to register and unregister cleanup
+functions. Functions thus registered are automatically executed upon normal
+interpreter termination.
+
+Note: the functions registered via this module are not called when the program
+is killed by a signal, when a Python fatal internal error is detected, or when
+:func:`os._exit` is called.
+
+
+.. function:: register(func[, *args[, **kargs]])
+
+ Register *func* as a function to be executed at termination. Any optional
+ arguments that are to be passed to *func* must be passed as arguments to
+ :func:`register`.
+
+ At normal program termination (for instance, if :func:`sys.exit` is called or
+ the main module's execution completes), all functions registered are called in
+ last in, first out order. The assumption is that lower level modules will
+ normally be imported before higher level modules and thus must be cleaned up
+ later.
+
+ If an exception is raised during execution of the exit handlers, a traceback is
+ printed (unless :exc:`SystemExit` is raised) and the exception information is
+ saved. After all exit handlers have had a chance to run the last exception to
+ be raised is re-raised.
+
+ .. versionchanged:: 2.6
+ This function now returns *func* which makes it possible to use it as a
+ decorator without binding the original name to ``None``.
+
+
+.. function:: unregister(func)
+
+ Remove a function *func* from the list of functions to be run at interpreter-
+ shutdown. After calling :func:`unregister`, *func* is guaranteed not to be
+ called when the interpreter shuts down.
+
+ .. versionadded:: 3.0
+
+
+.. seealso::
+
+ Module :mod:`readline`
+ Useful example of :mod:`atexit` to read and write :mod:`readline` history files.
+
+
+.. _atexit-example:
+
+:mod:`atexit` Example
+---------------------
+
+The following simple example demonstrates how a module can initialize a counter
+from a file when it is imported and save the counter's updated value
+automatically when the program terminates without relying on the application
+making an explicit call into this module at termination. ::
+
+ try:
+ _count = int(open("/tmp/counter").read())
+ except IOError:
+ _count = 0
+
+ def incrcounter(n):
+ global _count
+ _count = _count + n
+
+ def savecounter():
+ open("/tmp/counter", "w").write("%d" % _count)
+
+ import atexit
+ atexit.register(savecounter)
+
+Positional and keyword arguments may also be passed to :func:`register` to be
+passed along to the registered function when it is called::
+
+ def goodbye(name, adjective):
+ print 'Goodbye, %s, it was %s to meet you.' % (name, adjective)
+
+ import atexit
+ atexit.register(goodbye, 'Donny', 'nice')
+
+ # or:
+ atexit.register(goodbye, adjective='nice', name='Donny')
+
+Usage as a decorator::
+
+ import atexit
+
+ @atexit.register
+ def goodbye():
+ print "You are now leaving the Python sector."
+
+This obviously only works with functions that don't take arguments.
+
diff --git a/Doc/library/audioop.rst b/Doc/library/audioop.rst
new file mode 100644
index 0000000000..84a2690c6c
--- /dev/null
+++ b/Doc/library/audioop.rst
@@ -0,0 +1,261 @@
+
+:mod:`audioop` --- Manipulate raw audio data
+============================================
+
+.. module:: audioop
+ :synopsis: Manipulate raw audio data.
+
+
+The :mod:`audioop` module contains some useful operations on sound fragments.
+It operates on sound fragments consisting of signed integer samples 8, 16 or 32
+bits wide, stored in Python strings. All scalar items are integers, unless
+specified otherwise.
+
+.. index::
+ single: Intel/DVI ADPCM
+ single: ADPCM, Intel/DVI
+ single: a-LAW
+ single: u-LAW
+
+This module provides support for a-LAW, u-LAW and Intel/DVI ADPCM encodings.
+
+.. % This para is mostly here to provide an excuse for the index entries...
+
+A few of the more complicated operations only take 16-bit samples, otherwise the
+sample size (in bytes) is always a parameter of the operation.
+
+The module defines the following variables and functions:
+
+
+.. exception:: error
+
+ This exception is raised on all errors, such as unknown number of bytes per
+ sample, etc.
+
+
+.. function:: add(fragment1, fragment2, width)
+
+ Return a fragment which is the addition of the two samples passed as parameters.
+ *width* is the sample width in bytes, either ``1``, ``2`` or ``4``. Both
+ fragments should have the same length.
+
+
+.. function:: adpcm2lin(adpcmfragment, width, state)
+
+ Decode an Intel/DVI ADPCM coded fragment to a linear fragment. See the
+ description of :func:`lin2adpcm` for details on ADPCM coding. Return a tuple
+ ``(sample, newstate)`` where the sample has the width specified in *width*.
+
+
+.. function:: alaw2lin(fragment, width)
+
+ Convert sound fragments in a-LAW encoding to linearly encoded sound fragments.
+ a-LAW encoding always uses 8 bits samples, so *width* refers only to the sample
+ width of the output fragment here.
+
+ .. versionadded:: 2.5
+
+
+.. function:: avg(fragment, width)
+
+ Return the average over all samples in the fragment.
+
+
+.. function:: avgpp(fragment, width)
+
+ Return the average peak-peak value over all samples in the fragment. No
+ filtering is done, so the usefulness of this routine is questionable.
+
+
+.. function:: bias(fragment, width, bias)
+
+ Return a fragment that is the original fragment with a bias added to each
+ sample.
+
+
+.. function:: cross(fragment, width)
+
+ Return the number of zero crossings in the fragment passed as an argument.
+
+
+.. function:: findfactor(fragment, reference)
+
+ Return a factor *F* such that ``rms(add(fragment, mul(reference, -F)))`` is
+ minimal, i.e., return the factor with which you should multiply *reference* to
+ make it match as well as possible to *fragment*. The fragments should both
+ contain 2-byte samples.
+
+ The time taken by this routine is proportional to ``len(fragment)``.
+
+
+.. function:: findfit(fragment, reference)
+
+ Try to match *reference* as well as possible to a portion of *fragment* (which
+ should be the longer fragment). This is (conceptually) done by taking slices
+ out of *fragment*, using :func:`findfactor` to compute the best match, and
+ minimizing the result. The fragments should both contain 2-byte samples.
+ Return a tuple ``(offset, factor)`` where *offset* is the (integer) offset into
+ *fragment* where the optimal match started and *factor* is the (floating-point)
+ factor as per :func:`findfactor`.
+
+
+.. function:: findmax(fragment, length)
+
+ Search *fragment* for a slice of length *length* samples (not bytes!) with
+ maximum energy, i.e., return *i* for which ``rms(fragment[i*2:(i+length)*2])``
+ is maximal. The fragments should both contain 2-byte samples.
+
+ The routine takes time proportional to ``len(fragment)``.
+
+
+.. function:: getsample(fragment, width, index)
+
+ Return the value of sample *index* from the fragment.
+
+
+.. function:: lin2adpcm(fragment, width, state)
+
+ Convert samples to 4 bit Intel/DVI ADPCM encoding. ADPCM coding is an adaptive
+ coding scheme, whereby each 4 bit number is the difference between one sample
+ and the next, divided by a (varying) step. The Intel/DVI ADPCM algorithm has
+ been selected for use by the IMA, so it may well become a standard.
+
+ *state* is a tuple containing the state of the coder. The coder returns a tuple
+ ``(adpcmfrag, newstate)``, and the *newstate* should be passed to the next call
+ of :func:`lin2adpcm`. In the initial call, ``None`` can be passed as the state.
+ *adpcmfrag* is the ADPCM coded fragment packed 2 4-bit values per byte.
+
+
+.. function:: lin2alaw(fragment, width)
+
+ Convert samples in the audio fragment to a-LAW encoding and return this as a
+ Python string. a-LAW is an audio encoding format whereby you get a dynamic
+ range of about 13 bits using only 8 bit samples. It is used by the Sun audio
+ hardware, among others.
+
+ .. versionadded:: 2.5
+
+
+.. function:: lin2lin(fragment, width, newwidth)
+
+ Convert samples between 1-, 2- and 4-byte formats.
+
+
+.. function:: lin2ulaw(fragment, width)
+
+ Convert samples in the audio fragment to u-LAW encoding and return this as a
+ Python string. u-LAW is an audio encoding format whereby you get a dynamic
+ range of about 14 bits using only 8 bit samples. It is used by the Sun audio
+ hardware, among others.
+
+
+.. function:: minmax(fragment, width)
+
+ Return a tuple consisting of the minimum and maximum values of all samples in
+ the sound fragment.
+
+
+.. function:: max(fragment, width)
+
+ Return the maximum of the *absolute value* of all samples in a fragment.
+
+
+.. function:: maxpp(fragment, width)
+
+ Return the maximum peak-peak value in the sound fragment.
+
+
+.. function:: mul(fragment, width, factor)
+
+ Return a fragment that has all samples in the original fragment multiplied by
+ the floating-point value *factor*. Overflow is silently ignored.
+
+
+.. function:: ratecv(fragment, width, nchannels, inrate, outrate, state[, weightA[, weightB]])
+
+ Convert the frame rate of the input fragment.
+
+ *state* is a tuple containing the state of the converter. The converter returns
+ a tuple ``(newfragment, newstate)``, and *newstate* should be passed to the next
+ call of :func:`ratecv`. The initial call should pass ``None`` as the state.
+
+ The *weightA* and *weightB* arguments are parameters for a simple digital filter
+ and default to ``1`` and ``0`` respectively.
+
+
+.. function:: reverse(fragment, width)
+
+ Reverse the samples in a fragment and returns the modified fragment.
+
+
+.. function:: rms(fragment, width)
+
+ Return the root-mean-square of the fragment, i.e. ``sqrt(sum(S_i^2)/n)``.
+
+ This is a measure of the power in an audio signal.
+
+
+.. function:: tomono(fragment, width, lfactor, rfactor)
+
+ Convert a stereo fragment to a mono fragment. The left channel is multiplied by
+ *lfactor* and the right channel by *rfactor* before adding the two channels to
+ give a mono signal.
+
+
+.. function:: tostereo(fragment, width, lfactor, rfactor)
+
+ Generate a stereo fragment from a mono fragment. Each pair of samples in the
+ stereo fragment are computed from the mono sample, whereby left channel samples
+ are multiplied by *lfactor* and right channel samples by *rfactor*.
+
+
+.. function:: ulaw2lin(fragment, width)
+
+ Convert sound fragments in u-LAW encoding to linearly encoded sound fragments.
+ u-LAW encoding always uses 8 bits samples, so *width* refers only to the sample
+ width of the output fragment here.
+
+Note that operations such as :func:`mul` or :func:`max` make no distinction
+between mono and stereo fragments, i.e. all samples are treated equal. If this
+is a problem the stereo fragment should be split into two mono fragments first
+and recombined later. Here is an example of how to do that::
+
+ def mul_stereo(sample, width, lfactor, rfactor):
+ lsample = audioop.tomono(sample, width, 1, 0)
+ rsample = audioop.tomono(sample, width, 0, 1)
+ lsample = audioop.mul(sample, width, lfactor)
+ rsample = audioop.mul(sample, width, rfactor)
+ lsample = audioop.tostereo(lsample, width, 1, 0)
+ rsample = audioop.tostereo(rsample, width, 0, 1)
+ return audioop.add(lsample, rsample, width)
+
+If you use the ADPCM coder to build network packets and you want your protocol
+to be stateless (i.e. to be able to tolerate packet loss) you should not only
+transmit the data but also the state. Note that you should send the *initial*
+state (the one you passed to :func:`lin2adpcm`) along to the decoder, not the
+final state (as returned by the coder). If you want to use
+:func:`struct.struct` to store the state in binary you can code the first
+element (the predicted value) in 16 bits and the second (the delta index) in 8.
+
+The ADPCM coders have never been tried against other ADPCM coders, only against
+themselves. It could well be that I misinterpreted the standards in which case
+they will not be interoperable with the respective standards.
+
+The :func:`find\*` routines might look a bit funny at first sight. They are
+primarily meant to do echo cancellation. A reasonably fast way to do this is to
+pick the most energetic piece of the output sample, locate that in the input
+sample and subtract the whole output sample from the input sample::
+
+ def echocancel(outputdata, inputdata):
+ pos = audioop.findmax(outputdata, 800) # one tenth second
+ out_test = outputdata[pos*2:]
+ in_test = inputdata[pos*2:]
+ ipos, factor = audioop.findfit(in_test, out_test)
+ # Optional (for better cancellation):
+ # factor = audioop.findfactor(in_test[ipos*2:ipos*2+len(out_test)],
+ # out_test)
+ prefill = '\0'*(pos+ipos)*2
+ postfill = '\0'*(len(inputdata)-len(prefill)-len(outputdata))
+ outputdata = prefill + audioop.mul(outputdata,2,-factor) + postfill
+ return audioop.add(inputdata, outputdata, 2)
+
diff --git a/Doc/library/autogil.rst b/Doc/library/autogil.rst
new file mode 100644
index 0000000000..93f0d0460b
--- /dev/null
+++ b/Doc/library/autogil.rst
@@ -0,0 +1,30 @@
+
+:mod:`autoGIL` --- Global Interpreter Lock handling in event loops
+==================================================================
+
+.. module:: autoGIL
+ :platform: Mac
+ :synopsis: Global Interpreter Lock handling in event loops.
+.. moduleauthor:: Just van Rossum <just@letterror.com>
+
+
+The :mod:`autoGIL` module provides a function :func:`installAutoGIL` that
+automatically locks and unlocks Python's Global Interpreter Lock when running an
+event loop.
+
+
+.. exception:: AutoGILError
+
+ Raised if the observer callback cannot be installed, for example because the
+ current thread does not have a run loop.
+
+
+.. function:: installAutoGIL()
+
+ Install an observer callback in the event loop (CFRunLoop) for the current
+ thread, that will lock and unlock the Global Interpreter Lock (GIL) at
+ appropriate times, allowing other Python threads to run while the event loop is
+ idle.
+
+ Availability: OSX 10.1 or later.
+
diff --git a/Doc/library/base64.rst b/Doc/library/base64.rst
new file mode 100644
index 0000000000..daa8fd5610
--- /dev/null
+++ b/Doc/library/base64.rst
@@ -0,0 +1,172 @@
+
+:mod:`base64` --- RFC 3548: Base16, Base32, Base64 Data Encodings
+=================================================================
+
+.. module:: base64
+ :synopsis: RFC 3548: Base16, Base32, Base64 Data Encodings
+
+
+.. index::
+ pair: base64; encoding
+ single: MIME; base64 encoding
+
+This module provides data encoding and decoding as specified in :rfc:`3548`.
+This standard defines the Base16, Base32, and Base64 algorithms for encoding and
+decoding arbitrary binary strings into text strings that can be safely sent by
+email, used as parts of URLs, or included as part of an HTTP POST request. The
+encoding algorithm is not the same as the :program:`uuencode` program.
+
+There are two interfaces provided by this module. The modern interface supports
+encoding and decoding string objects using all three alphabets. The legacy
+interface provides for encoding and decoding to and from file-like objects as
+well as strings, but only using the Base64 standard alphabet.
+
+The modern interface, which was introduced in Python 2.4, provides:
+
+
+.. function:: b64encode(s[, altchars])
+
+ Encode a string use Base64.
+
+ *s* is the string to encode. Optional *altchars* must be a string of at least
+ length 2 (additional characters are ignored) which specifies an alternative
+ alphabet for the ``+`` and ``/`` characters. This allows an application to e.g.
+ generate URL or filesystem safe Base64 strings. The default is ``None``, for
+ which the standard Base64 alphabet is used.
+
+ The encoded string is returned.
+
+
+.. function:: b64decode(s[, altchars])
+
+ Decode a Base64 encoded string.
+
+ *s* is the string to decode. Optional *altchars* must be a string of at least
+ length 2 (additional characters are ignored) which specifies the alternative
+ alphabet used instead of the ``+`` and ``/`` characters.
+
+ The decoded string is returned. A :exc:`TypeError` is raised if *s* were
+ incorrectly padded or if there are non-alphabet characters present in the
+ string.
+
+
+.. function:: standard_b64encode(s)
+
+ Encode string *s* using the standard Base64 alphabet.
+
+
+.. function:: standard_b64decode(s)
+
+ Decode string *s* using the standard Base64 alphabet.
+
+
+.. function:: urlsafe_b64encode(s)
+
+ Encode string *s* using a URL-safe alphabet, which substitutes ``-`` instead of
+ ``+`` and ``_`` instead of ``/`` in the standard Base64 alphabet.
+
+
+.. function:: urlsafe_b64decode(s)
+
+ Decode string *s* using a URL-safe alphabet, which substitutes ``-`` instead of
+ ``+`` and ``_`` instead of ``/`` in the standard Base64 alphabet.
+
+
+.. function:: b32encode(s)
+
+ Encode a string using Base32. *s* is the string to encode. The encoded string
+ is returned.
+
+
+.. function:: b32decode(s[, casefold[, map01]])
+
+ Decode a Base32 encoded string.
+
+ *s* is the string to decode. Optional *casefold* is a flag specifying whether a
+ lowercase alphabet is acceptable as input. For security purposes, the default
+ is ``False``.
+
+ :rfc:`3548` allows for optional mapping of the digit 0 (zero) to the letter O
+ (oh), and for optional mapping of the digit 1 (one) to either the letter I (eye)
+ or letter L (el). The optional argument *map01* when not ``None``, specifies
+ which letter the digit 1 should be mapped to (when *map01* is not ``None``, the
+ digit 0 is always mapped to the letter O). For security purposes the default is
+ ``None``, so that 0 and 1 are not allowed in the input.
+
+ The decoded string is returned. A :exc:`TypeError` is raised if *s* were
+ incorrectly padded or if there are non-alphabet characters present in the
+ string.
+
+
+.. function:: b16encode(s)
+
+ Encode a string using Base16.
+
+ *s* is the string to encode. The encoded string is returned.
+
+
+.. function:: b16decode(s[, casefold])
+
+ Decode a Base16 encoded string.
+
+ *s* is the string to decode. Optional *casefold* is a flag specifying whether a
+ lowercase alphabet is acceptable as input. For security purposes, the default
+ is ``False``.
+
+ The decoded string is returned. A :exc:`TypeError` is raised if *s* were
+ incorrectly padded or if there are non-alphabet characters present in the
+ string.
+
+The legacy interface:
+
+
+.. function:: decode(input, output)
+
+ Decode the contents of the *input* file and write the resulting binary data to
+ the *output* file. *input* and *output* must either be file objects or objects
+ that mimic the file object interface. *input* will be read until
+ ``input.read()`` returns an empty string.
+
+
+.. function:: decodestring(s)
+
+ Decode the string *s*, which must contain one or more lines of base64 encoded
+ data, and return a string containing the resulting binary data.
+
+
+.. function:: encode(input, output)
+
+ Encode the contents of the *input* file and write the resulting base64 encoded
+ data to the *output* file. *input* and *output* must either be file objects or
+ objects that mimic the file object interface. *input* will be read until
+ ``input.read()`` returns an empty string. :func:`encode` returns the encoded
+ data plus a trailing newline character (``'\n'``).
+
+
+.. function:: encodestring(s)
+
+ Encode the string *s*, which can contain arbitrary binary data, and return a
+ string containing one or more lines of base64-encoded data.
+ :func:`encodestring` returns a string containing one or more lines of
+ base64-encoded data always including an extra trailing newline (``'\n'``).
+
+An example usage of the module::
+
+ >>> import base64
+ >>> encoded = base64.b64encode('data to be encoded')
+ >>> encoded
+ 'ZGF0YSB0byBiZSBlbmNvZGVk'
+ >>> data = base64.b64decode(encoded)
+ >>> data
+ 'data to be encoded'
+
+
+.. seealso::
+
+ Module :mod:`binascii`
+ Support module containing ASCII-to-binary and binary-to-ASCII conversions.
+
+ :rfc:`1521` - MIME (Multipurpose Internet Mail Extensions) Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies
+ Section 5.2, "Base64 Content-Transfer-Encoding," provides the definition of the
+ base64 encoding.
+
diff --git a/Doc/library/basehttpserver.rst b/Doc/library/basehttpserver.rst
new file mode 100644
index 0000000000..2e8d6a3806
--- /dev/null
+++ b/Doc/library/basehttpserver.rst
@@ -0,0 +1,254 @@
+
+:mod:`BaseHTTPServer` --- Basic HTTP server
+===========================================
+
+.. module:: BaseHTTPServer
+ :synopsis: Basic HTTP server (base class for SimpleHTTPServer and CGIHTTPServer).
+
+
+.. index::
+ pair: WWW; server
+ pair: HTTP; protocol
+ single: URL
+ single: httpd
+
+.. index::
+ module: SimpleHTTPServer
+ module: CGIHTTPServer
+
+This module defines two classes for implementing HTTP servers (Web servers).
+Usually, this module isn't used directly, but is used as a basis for building
+functioning Web servers. See the :mod:`SimpleHTTPServer` and
+:mod:`CGIHTTPServer` modules.
+
+The first class, :class:`HTTPServer`, is a :class:`SocketServer.TCPServer`
+subclass. It creates and listens at the HTTP socket, dispatching the requests
+to a handler. Code to create and run the server looks like this::
+
+ def run(server_class=BaseHTTPServer.HTTPServer,
+ handler_class=BaseHTTPServer.BaseHTTPRequestHandler):
+ server_address = ('', 8000)
+ httpd = server_class(server_address, handler_class)
+ httpd.serve_forever()
+
+
+.. class:: HTTPServer(server_address, RequestHandlerClass)
+
+ This class builds on the :class:`TCPServer` class by storing the server address
+ as instance variables named :attr:`server_name` and :attr:`server_port`. The
+ server is accessible by the handler, typically through the handler's
+ :attr:`server` instance variable.
+
+
+.. class:: BaseHTTPRequestHandler(request, client_address, server)
+
+ This class is used to handle the HTTP requests that arrive at the server. By
+ itself, it cannot respond to any actual HTTP requests; it must be subclassed to
+ handle each request method (e.g. GET or POST). :class:`BaseHTTPRequestHandler`
+ provides a number of class and instance variables, and methods for use by
+ subclasses.
+
+ The handler will parse the request and the headers, then call a method specific
+ to the request type. The method name is constructed from the request. For
+ example, for the request method ``SPAM``, the :meth:`do_SPAM` method will be
+ called with no arguments. All of the relevant information is stored in instance
+ variables of the handler. Subclasses should not need to override or extend the
+ :meth:`__init__` method.
+
+:class:`BaseHTTPRequestHandler` has the following instance variables:
+
+
+.. attribute:: BaseHTTPRequestHandler.client_address
+
+ Contains a tuple of the form ``(host, port)`` referring to the client's address.
+
+
+.. attribute:: BaseHTTPRequestHandler.command
+
+ Contains the command (request type). For example, ``'GET'``.
+
+
+.. attribute:: BaseHTTPRequestHandler.path
+
+ Contains the request path.
+
+
+.. attribute:: BaseHTTPRequestHandler.request_version
+
+ Contains the version string from the request. For example, ``'HTTP/1.0'``.
+
+
+.. attribute:: BaseHTTPRequestHandler.headers
+
+ Holds an instance of the class specified by the :attr:`MessageClass` class
+ variable. This instance parses and manages the headers in the HTTP request.
+
+
+.. attribute:: BaseHTTPRequestHandler.rfile
+
+ Contains an input stream, positioned at the start of the optional input data.
+
+
+.. attribute:: BaseHTTPRequestHandler.wfile
+
+ Contains the output stream for writing a response back to the client. Proper
+ adherence to the HTTP protocol must be used when writing to this stream.
+
+:class:`BaseHTTPRequestHandler` has the following class variables:
+
+
+.. attribute:: BaseHTTPRequestHandler.server_version
+
+ Specifies the server software version. You may want to override this. The
+ format is multiple whitespace-separated strings, where each string is of the
+ form name[/version]. For example, ``'BaseHTTP/0.2'``.
+
+
+.. attribute:: BaseHTTPRequestHandler.sys_version
+
+ Contains the Python system version, in a form usable by the
+ :attr:`version_string` method and the :attr:`server_version` class variable. For
+ example, ``'Python/1.4'``.
+
+
+.. attribute:: BaseHTTPRequestHandler.error_message_format
+
+ Specifies a format string for building an error response to the client. It uses
+ parenthesized, keyed format specifiers, so the format operand must be a
+ dictionary. The *code* key should be an integer, specifying the numeric HTTP
+ error code value. *message* should be a string containing a (detailed) error
+ message of what occurred, and *explain* should be an explanation of the error
+ code number. Default *message* and *explain* values can found in the *responses*
+ class variable.
+
+
+.. attribute:: BaseHTTPRequestHandler.protocol_version
+
+ This specifies the HTTP protocol version used in responses. If set to
+ ``'HTTP/1.1'``, the server will permit HTTP persistent connections; however,
+ your server *must* then include an accurate ``Content-Length`` header (using
+ :meth:`send_header`) in all of its responses to clients. For backwards
+ compatibility, the setting defaults to ``'HTTP/1.0'``.
+
+
+.. attribute:: BaseHTTPRequestHandler.MessageClass
+
+ .. index:: single: Message (in module mimetools)
+
+ Specifies a :class:`rfc822.Message`\ -like class to parse HTTP headers.
+ Typically, this is not overridden, and it defaults to
+ :class:`mimetools.Message`.
+
+
+.. attribute:: BaseHTTPRequestHandler.responses
+
+ This variable contains a mapping of error code integers to two-element tuples
+ containing a short and long message. For example, ``{code: (shortmessage,
+ longmessage)}``. The *shortmessage* is usually used as the *message* key in an
+ error response, and *longmessage* as the *explain* key (see the
+ :attr:`error_message_format` class variable).
+
+A :class:`BaseHTTPRequestHandler` instance has the following methods:
+
+
+.. method:: BaseHTTPRequestHandler.handle()
+
+ Calls :meth:`handle_one_request` once (or, if persistent connections are
+ enabled, multiple times) to handle incoming HTTP requests. You should never need
+ to override it; instead, implement appropriate :meth:`do_\*` methods.
+
+
+.. method:: BaseHTTPRequestHandler.handle_one_request()
+
+ This method will parse and dispatch the request to the appropriate :meth:`do_\*`
+ method. You should never need to override it.
+
+
+.. method:: BaseHTTPRequestHandler.send_error(code[, message])
+
+ Sends and logs a complete error reply to the client. The numeric *code*
+ specifies the HTTP error code, with *message* as optional, more specific text. A
+ complete set of headers is sent, followed by text composed using the
+ :attr:`error_message_format` class variable.
+
+
+.. method:: BaseHTTPRequestHandler.send_response(code[, message])
+
+ Sends a response header and logs the accepted request. The HTTP response line is
+ sent, followed by *Server* and *Date* headers. The values for these two headers
+ are picked up from the :meth:`version_string` and :meth:`date_time_string`
+ methods, respectively.
+
+
+.. method:: BaseHTTPRequestHandler.send_header(keyword, value)
+
+ Writes a specific HTTP header to the output stream. *keyword* should specify the
+ header keyword, with *value* specifying its value.
+
+
+.. method:: BaseHTTPRequestHandler.end_headers()
+
+ Sends a blank line, indicating the end of the HTTP headers in the response.
+
+
+.. method:: BaseHTTPRequestHandler.log_request([code[, size]])
+
+ Logs an accepted (successful) request. *code* should specify the numeric HTTP
+ code associated with the response. If a size of the response is available, then
+ it should be passed as the *size* parameter.
+
+
+.. method:: BaseHTTPRequestHandler.log_error(...)
+
+ Logs an error when a request cannot be fulfilled. By default, it passes the
+ message to :meth:`log_message`, so it takes the same arguments (*format* and
+ additional values).
+
+
+.. method:: BaseHTTPRequestHandler.log_message(format, ...)
+
+ Logs an arbitrary message to ``sys.stderr``. This is typically overridden to
+ create custom error logging mechanisms. The *format* argument is a standard
+ printf-style format string, where the additional arguments to
+ :meth:`log_message` are applied as inputs to the formatting. The client address
+ and current date and time are prefixed to every message logged.
+
+
+.. method:: BaseHTTPRequestHandler.version_string()
+
+ Returns the server software's version string. This is a combination of the
+ :attr:`server_version` and :attr:`sys_version` class variables.
+
+
+.. method:: BaseHTTPRequestHandler.date_time_string([timestamp])
+
+ Returns the date and time given by *timestamp* (which must be in the format
+ returned by :func:`time.time`), formatted for a message header. If *timestamp*
+ is omitted, it uses the current date and time.
+
+ The result looks like ``'Sun, 06 Nov 1994 08:49:37 GMT'``.
+
+ .. versionadded:: 2.5
+ The *timestamp* parameter.
+
+
+.. method:: BaseHTTPRequestHandler.log_date_time_string()
+
+ Returns the current date and time, formatted for logging.
+
+
+.. method:: BaseHTTPRequestHandler.address_string()
+
+ Returns the client address, formatted for logging. A name lookup is performed on
+ the client's IP address.
+
+
+.. seealso::
+
+ Module :mod:`CGIHTTPServer`
+ Extended request handler that supports CGI scripts.
+
+ Module :mod:`SimpleHTTPServer`
+ Basic request handler that limits response to files actually under the document
+ root.
+
diff --git a/Doc/library/binascii.rst b/Doc/library/binascii.rst
new file mode 100644
index 0000000000..ffea2324a6
--- /dev/null
+++ b/Doc/library/binascii.rst
@@ -0,0 +1,161 @@
+
+:mod:`binascii` --- Convert between binary and ASCII
+====================================================
+
+.. module:: binascii
+ :synopsis: Tools for converting between binary and various ASCII-encoded binary
+ representations.
+
+
+.. index::
+ module: uu
+ module: base64
+ module: binhex
+
+The :mod:`binascii` module contains a number of methods to convert between
+binary and various ASCII-encoded binary representations. Normally, you will not
+use these functions directly but use wrapper modules like :mod:`uu`,
+:mod:`base64`, or :mod:`binhex` instead. The :mod:`binascii` module contains
+low-level functions written in C for greater speed that are used by the
+higher-level modules.
+
+The :mod:`binascii` module defines the following functions:
+
+
+.. function:: a2b_uu(string)
+
+ Convert a single line of uuencoded data back to binary and return the binary
+ data. Lines normally contain 45 (binary) bytes, except for the last line. Line
+ data may be followed by whitespace.
+
+
+.. function:: b2a_uu(data)
+
+ Convert binary data to a line of ASCII characters, the return value is the
+ converted line, including a newline char. The length of *data* should be at most
+ 45.
+
+
+.. function:: a2b_base64(string)
+
+ Convert a block of base64 data back to binary and return the binary data. More
+ than one line may be passed at a time.
+
+
+.. function:: b2a_base64(data)
+
+ Convert binary data to a line of ASCII characters in base64 coding. The return
+ value is the converted line, including a newline char. The length of *data*
+ should be at most 57 to adhere to the base64 standard.
+
+
+.. function:: a2b_qp(string[, header])
+
+ Convert a block of quoted-printable data back to binary and return the binary
+ data. More than one line may be passed at a time. If the optional argument
+ *header* is present and true, underscores will be decoded as spaces.
+
+
+.. function:: b2a_qp(data[, quotetabs, istext, header])
+
+ Convert binary data to a line(s) of ASCII characters in quoted-printable
+ encoding. The return value is the converted line(s). If the optional argument
+ *quotetabs* is present and true, all tabs and spaces will be encoded. If the
+ optional argument *istext* is present and true, newlines are not encoded but
+ trailing whitespace will be encoded. If the optional argument *header* is
+ present and true, spaces will be encoded as underscores per RFC1522. If the
+ optional argument *header* is present and false, newline characters will be
+ encoded as well; otherwise linefeed conversion might corrupt the binary data
+ stream.
+
+
+.. function:: a2b_hqx(string)
+
+ Convert binhex4 formatted ASCII data to binary, without doing RLE-decompression.
+ The string should contain a complete number of binary bytes, or (in case of the
+ last portion of the binhex4 data) have the remaining bits zero.
+
+
+.. function:: rledecode_hqx(data)
+
+ Perform RLE-decompression on the data, as per the binhex4 standard. The
+ algorithm uses ``0x90`` after a byte as a repeat indicator, followed by a count.
+ A count of ``0`` specifies a byte value of ``0x90``. The routine returns the
+ decompressed data, unless data input data ends in an orphaned repeat indicator,
+ in which case the :exc:`Incomplete` exception is raised.
+
+
+.. function:: rlecode_hqx(data)
+
+ Perform binhex4 style RLE-compression on *data* and return the result.
+
+
+.. function:: b2a_hqx(data)
+
+ Perform hexbin4 binary-to-ASCII translation and return the resulting string. The
+ argument should already be RLE-coded, and have a length divisible by 3 (except
+ possibly the last fragment).
+
+
+.. function:: crc_hqx(data, crc)
+
+ Compute the binhex4 crc value of *data*, starting with an initial *crc* and
+ returning the result.
+
+
+.. function:: crc32(data[, crc])
+
+ Compute CRC-32, the 32-bit checksum of data, starting with an initial crc. This
+ is consistent with the ZIP file checksum. Since the algorithm is designed for
+ use as a checksum algorithm, it is not suitable for use as a general hash
+ algorithm. Use as follows::
+
+ print binascii.crc32("hello world")
+ # Or, in two pieces:
+ crc = binascii.crc32("hello")
+ crc = binascii.crc32(" world", crc)
+ print crc
+
+
+.. function:: b2a_hex(data)
+ hexlify(data)
+
+ Return the hexadecimal representation of the binary *data*. Every byte of
+ *data* is converted into the corresponding 2-digit hex representation. The
+ resulting string is therefore twice as long as the length of *data*.
+
+
+.. function:: a2b_hex(hexstr)
+ unhexlify(hexstr)
+
+ Return the binary data represented by the hexadecimal string *hexstr*. This
+ function is the inverse of :func:`b2a_hex`. *hexstr* must contain an even number
+ of hexadecimal digits (which can be upper or lower case), otherwise a
+ :exc:`TypeError` is raised.
+
+
+.. exception:: Error
+
+ Exception raised on errors. These are usually programming errors.
+
+
+.. exception:: Incomplete
+
+ Exception raised on incomplete data. These are usually not programming errors,
+ but may be handled by reading a little more data and trying again.
+
+
+.. seealso::
+
+ Module :mod:`base64`
+ Support for base64 encoding used in MIME email messages.
+
+ Module :mod:`binhex`
+ Support for the binhex format used on the Macintosh.
+
+ Module :mod:`uu`
+ Support for UU encoding used on Unix.
+
+ Module :mod:`quopri`
+ Support for quoted-printable encoding used in MIME email messages.
+
diff --git a/Doc/library/binhex.rst b/Doc/library/binhex.rst
new file mode 100644
index 0000000000..3b0485c175
--- /dev/null
+++ b/Doc/library/binhex.rst
@@ -0,0 +1,59 @@
+
+:mod:`binhex` --- Encode and decode binhex4 files
+=================================================
+
+.. module:: binhex
+ :synopsis: Encode and decode files in binhex4 format.
+
+
+This module encodes and decodes files in binhex4 format, a format allowing
+representation of Macintosh files in ASCII. On the Macintosh, both forks of a
+file and the finder information are encoded (or decoded), on other platforms
+only the data fork is handled.
+
+The :mod:`binhex` module defines the following functions:
+
+
+.. function:: binhex(input, output)
+
+ Convert a binary file with filename *input* to binhex file *output*. The
+ *output* parameter can either be a filename or a file-like object (any object
+ supporting a :meth:`write` and :meth:`close` method).
+
+
+.. function:: hexbin(input[, output])
+
+ Decode a binhex file *input*. *input* may be a filename or a file-like object
+ supporting :meth:`read` and :meth:`close` methods. The resulting file is written
+ to a file named *output*, unless the argument is omitted in which case the
+ output filename is read from the binhex file.
+
+The following exception is also defined:
+
+
+.. exception:: Error
+
+ Exception raised when something can't be encoded using the binhex format (for
+ example, a filename is too long to fit in the filename field), or when input is
+ not properly encoded binhex data.
+
+
+.. seealso::
+
+ Module :mod:`binascii`
+ Support module containing ASCII-to-binary and binary-to-ASCII conversions.
+
+
+.. _binhex-notes:
+
+Notes
+-----
+
+There is an alternative, more powerful interface to the coder and decoder, see
+the source for details.
+
+If you code or decode textfiles on non-Macintosh platforms they will still use
+the Macintosh newline convention (carriage-return as end of line).
+
+As of this writing, :func:`hexbin` appears to not work in all cases.
+
diff --git a/Doc/library/bisect.rst b/Doc/library/bisect.rst
new file mode 100644
index 0000000000..b8eb348cd3
--- /dev/null
+++ b/Doc/library/bisect.rst
@@ -0,0 +1,92 @@
+
+:mod:`bisect` --- Array bisection algorithm
+===========================================
+
+.. module:: bisect
+ :synopsis: Array bisection algorithms for binary searching.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. % LaTeX produced by Fred L. Drake, Jr. <fdrake@acm.org>, with an
+.. % example based on the PyModules FAQ entry by Aaron Watters
+.. % <arw@pythonpros.com>.
+
+This module provides support for maintaining a list in sorted order without
+having to sort the list after each insertion. For long lists of items with
+expensive comparison operations, this can be an improvement over the more common
+approach. The module is called :mod:`bisect` because it uses a basic bisection
+algorithm to do its work. The source code may be most useful as a working
+example of the algorithm (the boundary conditions are already right!).
+
+The following functions are provided:
+
+
+.. function:: bisect_left(list, item[, lo[, hi]])
+
+ Locate the proper insertion point for *item* in *list* to maintain sorted order.
+ The parameters *lo* and *hi* may be used to specify a subset of the list which
+ should be considered; by default the entire list is used. If *item* is already
+ present in *list*, the insertion point will be before (to the left of) any
+ existing entries. The return value is suitable for use as the first parameter
+ to ``list.insert()``. This assumes that *list* is already sorted.
+
+ .. versionadded:: 2.1
+
+
+.. function:: bisect_right(list, item[, lo[, hi]])
+
+ Similar to :func:`bisect_left`, but returns an insertion point which comes after
+ (to the right of) any existing entries of *item* in *list*.
+
+ .. versionadded:: 2.1
+
+
+.. function:: bisect(...)
+
+ Alias for :func:`bisect_right`.
+
+
+.. function:: insort_left(list, item[, lo[, hi]])
+
+ Insert *item* in *list* in sorted order. This is equivalent to
+ ``list.insert(bisect.bisect_left(list, item, lo, hi), item)``. This assumes
+ that *list* is already sorted.
+
+ .. versionadded:: 2.1
+
+
+.. function:: insort_right(list, item[, lo[, hi]])
+
+ Similar to :func:`insort_left`, but inserting *item* in *list* after any
+ existing entries of *item*.
+
+ .. versionadded:: 2.1
+
+
+.. function:: insort(...)
+
+ Alias for :func:`insort_right`.
+
+
+Examples
+--------
+
+.. _bisect-example:
+
+The :func:`bisect` function is generally useful for categorizing numeric data.
+This example uses :func:`bisect` to look up a letter grade for an exam total
+(say) based on a set of ordered numeric breakpoints: 85 and up is an 'A', 75..84
+is a 'B', etc. ::
+
+ >>> grades = "FEDCBA"
+ >>> breakpoints = [30, 44, 66, 75, 85]
+ >>> from bisect import bisect
+ >>> def grade(total):
+ ... return grades[bisect(breakpoints, total)]
+ ...
+ >>> grade(66)
+ 'C'
+ >>> map(grade, [33, 99, 77, 44, 12, 88])
+ ['E', 'A', 'B', 'D', 'F', 'A']
+
+
diff --git a/Doc/library/bsddb.rst b/Doc/library/bsddb.rst
new file mode 100644
index 0000000000..55b7c7d842
--- /dev/null
+++ b/Doc/library/bsddb.rst
@@ -0,0 +1,211 @@
+
+:mod:`bsddb` --- Interface to Berkeley DB library
+=================================================
+
+.. module:: bsddb
+ :synopsis: Interface to Berkeley DB database library
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+The :mod:`bsddb` module provides an interface to the Berkeley DB library. Users
+can create hash, btree or record based library files using the appropriate open
+call. Bsddb objects behave generally like dictionaries. Keys and values must be
+strings, however, so to use other objects as keys or to store other kinds of
+objects the user must serialize them somehow, typically using
+:func:`marshal.dumps` or :func:`pickle.dumps`.
+
+The :mod:`bsddb` module requires a Berkeley DB library version from 3.3 thru
+4.5.
+
+
+.. seealso::
+
+ http://pybsddb.sourceforge.net/
+ The website with documentation for the :mod:`bsddb.db` Python Berkeley DB
+ interface that closely mirrors the object oriented interface provided in
+ Berkeley DB 3 and 4.
+
+ http://www.oracle.com/database/berkeley-db/
+ The Berkeley DB library.
+
+A more modern DB, DBEnv and DBSequence object interface is available in the
+:mod:`bsddb.db` module which closely matches the Berkeley DB C API documented at
+the above URLs. Additional features provided by the :mod:`bsddb.db` API include
+fine tuning, transactions, logging, and multiprocess concurrent database access.
+
+The following is a description of the legacy :mod:`bsddb` interface compatible
+with the old Python bsddb module. Starting in Python 2.5 this interface should
+be safe for multithreaded access. The :mod:`bsddb.db` API is recommended for
+threading users as it provides better control.
+
+The :mod:`bsddb` module defines the following functions that create objects that
+access the appropriate type of Berkeley DB file. The first two arguments of
+each function are the same. For ease of portability, only the first two
+arguments should be used in most instances.
+
+
+.. function:: hashopen(filename[, flag[, mode[, pgsize[, ffactor[, nelem[, cachesize[, lorder[, hflags]]]]]]]])
+
+ Open the hash format file named *filename*. Files never intended to be
+ preserved on disk may be created by passing ``None`` as the *filename*. The
+ optional *flag* identifies the mode used to open the file. It may be ``'r'``
+ (read only), ``'w'`` (read-write) , ``'c'`` (read-write - create if necessary;
+ the default) or ``'n'`` (read-write - truncate to zero length). The other
+ arguments are rarely used and are just passed to the low-level :cfunc:`dbopen`
+ function. Consult the Berkeley DB documentation for their use and
+ interpretation.
+
+
+.. function:: btopen(filename[, flag[, mode[, btflags[, cachesize[, maxkeypage[, minkeypage[, pgsize[, lorder]]]]]]]])
+
+ Open the btree format file named *filename*. Files never intended to be
+ preserved on disk may be created by passing ``None`` as the *filename*. The
+ optional *flag* identifies the mode used to open the file. It may be ``'r'``
+ (read only), ``'w'`` (read-write), ``'c'`` (read-write - create if necessary;
+ the default) or ``'n'`` (read-write - truncate to zero length). The other
+ arguments are rarely used and are just passed to the low-level dbopen function.
+ Consult the Berkeley DB documentation for their use and interpretation.
+
+
+.. function:: rnopen(filename[, flag[, mode[, rnflags[, cachesize[, pgsize[, lorder[, rlen[, delim[, source[, pad]]]]]]]]]])
+
+ Open a DB record format file named *filename*. Files never intended to be
+ preserved on disk may be created by passing ``None`` as the *filename*. The
+ optional *flag* identifies the mode used to open the file. It may be ``'r'``
+ (read only), ``'w'`` (read-write), ``'c'`` (read-write - create if necessary;
+ the default) or ``'n'`` (read-write - truncate to zero length). The other
+ arguments are rarely used and are just passed to the low-level dbopen function.
+ Consult the Berkeley DB documentation for their use and interpretation.
+
+
+.. class:: StringKeys(db)
+
+ Wrapper class around a DB object that supports string keys (rather than bytes).
+ All keys are encoded as UTF-8, then passed to the underlying object.
+
+ .. versionadded:: 3.0
+
+
+.. class:: StringValues(db)
+
+ Wrapper class around a DB object that supports string values (rather than bytes).
+ All values are encoded as UTF-8, then passed to the underlying object.
+
+ .. versionadded:: 3.0
+
+
+.. seealso::
+
+ Module :mod:`dbhash`
+ DBM-style interface to the :mod:`bsddb`
+
+
+.. _bsddb-objects:
+
+Hash, BTree and Record Objects
+------------------------------
+
+Once instantiated, hash, btree and record objects support the same methods as
+dictionaries. In addition, they support the methods listed below.
+
+.. versionchanged:: 2.3.1
+ Added dictionary methods.
+
+
+.. method:: bsddbobject.close()
+
+ Close the underlying file. The object can no longer be accessed. Since there
+ is no open :meth:`open` method for these objects, to open the file again a new
+ :mod:`bsddb` module open function must be called.
+
+
+.. method:: bsddbobject.keys()
+
+ Return the list of keys contained in the DB file. The order of the list is
+ unspecified and should not be relied on. In particular, the order of the list
+ returned is different for different file formats.
+
+
+.. method:: bsddbobject.has_key(key)
+
+ Return ``1`` if the DB file contains the argument as a key.
+
+
+.. method:: bsddbobject.set_location(key)
+
+ Set the cursor to the item indicated by *key* and return a tuple containing the
+ key and its value. For binary tree databases (opened using :func:`btopen`), if
+ *key* does not actually exist in the database, the cursor will point to the next
+ item in sorted order and return that key and value. For other databases,
+ :exc:`KeyError` will be raised if *key* is not found in the database.
+
+
+.. method:: bsddbobject.first()
+
+ Set the cursor to the first item in the DB file and return it. The order of
+ keys in the file is unspecified, except in the case of B-Tree databases. This
+ method raises :exc:`bsddb.error` if the database is empty.
+
+
+.. method:: bsddbobject.next()
+
+ Set the cursor to the next item in the DB file and return it. The order of
+ keys in the file is unspecified, except in the case of B-Tree databases.
+
+
+.. method:: bsddbobject.previous()
+
+ Set the cursor to the previous item in the DB file and return it. The order of
+ keys in the file is unspecified, except in the case of B-Tree databases. This
+ is not supported on hashtable databases (those opened with :func:`hashopen`).
+
+
+.. method:: bsddbobject.last()
+
+ Set the cursor to the last item in the DB file and return it. The order of keys
+ in the file is unspecified. This is not supported on hashtable databases (those
+ opened with :func:`hashopen`). This method raises :exc:`bsddb.error` if the
+ database is empty.
+
+
+.. method:: bsddbobject.sync()
+
+ Synchronize the database on disk.
+
+Example::
+
+ >>> import bsddb
+ >>> db = bsddb.btopen('/tmp/spam.db', 'c')
+ >>> for i in range(10): db['%d'%i] = '%d'% (i*i)
+ ...
+ >>> db['3']
+ '9'
+ >>> db.keys()
+ ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']
+ >>> db.first()
+ ('0', '0')
+ >>> db.next()
+ ('1', '1')
+ >>> db.last()
+ ('9', '81')
+ >>> db.set_location('2')
+ ('2', '4')
+ >>> db.previous()
+ ('1', '1')
+ >>> for k, v in db.iteritems():
+ ... print k, v
+ 0 0
+ 1 1
+ 2 4
+ 3 9
+ 4 16
+ 5 25
+ 6 36
+ 7 49
+ 8 64
+ 9 81
+ >>> '8' in db
+ True
+ >>> db.sync()
+ 0
+
diff --git a/Doc/library/bz2.rst b/Doc/library/bz2.rst
new file mode 100644
index 0000000000..a8c0911294
--- /dev/null
+++ b/Doc/library/bz2.rst
@@ -0,0 +1,181 @@
+
+:mod:`bz2` --- Compression compatible with :program:`bzip2`
+===========================================================
+
+.. module:: bz2
+ :synopsis: Interface to compression and decompression routines compatible with bzip2.
+.. moduleauthor:: Gustavo Niemeyer <niemeyer@conectiva.com>
+.. sectionauthor:: Gustavo Niemeyer <niemeyer@conectiva.com>
+
+
+.. versionadded:: 2.3
+
+This module provides a comprehensive interface for the bz2 compression library.
+It implements a complete file interface, one-shot (de)compression functions, and
+types for sequential (de)compression.
+
+Here is a resume of the features offered by the bz2 module:
+
+* :class:`BZ2File` class implements a complete file interface, including
+ :meth:`readline`, :meth:`readlines`, :meth:`writelines`, :meth:`seek`, etc;
+
+* :class:`BZ2File` class implements emulated :meth:`seek` support;
+
+* :class:`BZ2File` class implements universal newline support;
+
+* :class:`BZ2File` class offers an optimized line iteration using the readahead
+ algorithm borrowed from file objects;
+
+* Sequential (de)compression supported by :class:`BZ2Compressor` and
+ :class:`BZ2Decompressor` classes;
+
+* One-shot (de)compression supported by :func:`compress` and :func:`decompress`
+ functions;
+
+* Thread safety uses individual locking mechanism;
+
+* Complete inline documentation;
+
+
+(De)compression of files
+------------------------
+
+Handling of compressed files is offered by the :class:`BZ2File` class.
+
+
+.. class:: BZ2File(filename[, mode[, buffering[, compresslevel]]])
+
+ Open a bz2 file. Mode can be either ``'r'`` or ``'w'``, for reading (default)
+ or writing. When opened for writing, the file will be created if it doesn't
+ exist, and truncated otherwise. If *buffering* is given, ``0`` means unbuffered,
+ and larger numbers specify the buffer size; the default is ``0``. If
+ *compresslevel* is given, it must be a number between ``1`` and ``9``; the
+ default is ``9``. Add a ``'U'`` to mode to open the file for input with
+ universal newline support. Any line ending in the input file will be seen as a
+ ``'\n'`` in Python. Also, a file so opened gains the attribute
+ :attr:`newlines`; the value for this attribute is one of ``None`` (no newline
+ read yet), ``'\r'``, ``'\n'``, ``'\r\n'`` or a tuple containing all the newline
+ types seen. Universal newlines are available only when reading. Instances
+ support iteration in the same way as normal :class:`file` instances.
+
+
+.. method:: BZ2File.close()
+
+ Close the file. Sets data attribute :attr:`closed` to true. A closed file cannot
+ be used for further I/O operations. :meth:`close` may be called more than once
+ without error.
+
+
+.. method:: BZ2File.read([size])
+
+ Read at most *size* uncompressed bytes, returned as a string. If the *size*
+ argument is negative or omitted, read until EOF is reached.
+
+
+.. method:: BZ2File.readline([size])
+
+ Return the next line from the file, as a string, retaining newline. A
+ non-negative *size* argument limits the maximum number of bytes to return (an
+ incomplete line may be returned then). Return an empty string at EOF.
+
+
+.. method:: BZ2File.readlines([size])
+
+ Return a list of lines read. The optional *size* argument, if given, is an
+ approximate bound on the total number of bytes in the lines returned.
+
+
+.. method:: BZ2File.seek(offset[, whence])
+
+ Move to new file position. Argument *offset* is a byte count. Optional argument
+ *whence* defaults to ``os.SEEK_SET`` or ``0`` (offset from start of file; offset
+ should be ``>= 0``); other values are ``os.SEEK_CUR`` or ``1`` (move relative to
+ current position; offset can be positive or negative), and ``os.SEEK_END`` or
+ ``2`` (move relative to end of file; offset is usually negative, although many
+ platforms allow seeking beyond the end of a file).
+
+ Note that seeking of bz2 files is emulated, and depending on the parameters the
+ operation may be extremely slow.
+
+
+.. method:: BZ2File.tell()
+
+ Return the current file position, an integer (may be a long integer).
+
+
+.. method:: BZ2File.write(data)
+
+ Write string *data* to file. Note that due to buffering, :meth:`close` may be
+ needed before the file on disk reflects the data written.
+
+
+.. method:: BZ2File.writelines(sequence_of_strings)
+
+ Write the sequence of strings to the file. Note that newlines are not added. The
+ sequence can be any iterable object producing strings. This is equivalent to
+ calling write() for each string.
+
+
+Sequential (de)compression
+--------------------------
+
+Sequential compression and decompression is done using the classes
+:class:`BZ2Compressor` and :class:`BZ2Decompressor`.
+
+
+.. class:: BZ2Compressor([compresslevel])
+
+ Create a new compressor object. This object may be used to compress data
+ sequentially. If you want to compress data in one shot, use the :func:`compress`
+ function instead. The *compresslevel* parameter, if given, must be a number
+ between ``1`` and ``9``; the default is ``9``.
+
+
+.. method:: BZ2Compressor.compress(data)
+
+ Provide more data to the compressor object. It will return chunks of compressed
+ data whenever possible. When you've finished providing data to compress, call
+ the :meth:`flush` method to finish the compression process, and return what is
+ left in internal buffers.
+
+
+.. method:: BZ2Compressor.flush()
+
+ Finish the compression process and return what is left in internal buffers. You
+ must not use the compressor object after calling this method.
+
+
+.. class:: BZ2Decompressor()
+
+ Create a new decompressor object. This object may be used to decompress data
+ sequentially. If you want to decompress data in one shot, use the
+ :func:`decompress` function instead.
+
+
+.. method:: BZ2Decompressor.decompress(data)
+
+ Provide more data to the decompressor object. It will return chunks of
+ decompressed data whenever possible. If you try to decompress data after the end
+ of stream is found, :exc:`EOFError` will be raised. If any data was found after
+ the end of stream, it'll be ignored and saved in :attr:`unused_data` attribute.
+
+
+One-shot (de)compression
+------------------------
+
+One-shot compression and decompression is provided through the :func:`compress`
+and :func:`decompress` functions.
+
+
+.. function:: compress(data[, compresslevel])
+
+ Compress *data* in one shot. If you want to compress data sequentially, use an
+ instance of :class:`BZ2Compressor` instead. The *compresslevel* parameter, if
+ given, must be a number between ``1`` and ``9``; the default is ``9``.
+
+
+.. function:: decompress(data)
+
+ Decompress *data* in one shot. If you want to decompress data sequentially, use
+ an instance of :class:`BZ2Decompressor` instead.
+
diff --git a/Doc/library/calendar.rst b/Doc/library/calendar.rst
new file mode 100644
index 0000000000..68cbeb67e7
--- /dev/null
+++ b/Doc/library/calendar.rst
@@ -0,0 +1,326 @@
+
+:mod:`calendar` --- General calendar-related functions
+======================================================
+
+.. module:: calendar
+ :synopsis: Functions for working with calendars, including some emulation of the Unix cal
+ program.
+.. sectionauthor:: Drew Csillag <drew_csillag@geocities.com>
+
+
+This module allows you to output calendars like the Unix :program:`cal` program,
+and provides additional useful functions related to the calendar. By default,
+these calendars have Monday as the first day of the week, and Sunday as the last
+(the European convention). Use :func:`setfirstweekday` to set the first day of
+the week to Sunday (6) or to any other weekday. Parameters that specify dates
+are given as integers. For related
+functionality, see also the :mod:`datetime` and :mod:`time` modules.
+
+Most of these functions and classses rely on the :mod:`datetime` module which
+uses an idealized calendar, the current Gregorian calendar indefinitely extended
+in both directions. This matches the definition of the "proleptic Gregorian"
+calendar in Dershowitz and Reingold's book "Calendrical Calculations", where
+it's the base calendar for all computations.
+
+
+.. class:: Calendar([firstweekday])
+
+ Creates a :class:`Calendar` object. *firstweekday* is an integer specifying the
+ first day of the week. ``0`` is Monday (the default), ``6`` is Sunday.
+
+ A :class:`Calendar` object provides several methods that can be used for
+ preparing the calendar data for formatting. This class doesn't do any formatting
+ itself. This is the job of subclasses.
+
+ .. versionadded:: 2.5
+
+:class:`Calendar` instances have the following methods:
+
+
+.. method:: Calendar.iterweekdays(weekday)
+
+ Return an iterator for the week day numbers that will be used for one week. The
+ first number from the iterator will be the same as the number returned by
+ :meth:`firstweekday`.
+
+
+.. method:: Calendar.itermonthdates(year, month)
+
+ Return an iterator for the month *month* (1-12) in the year *year*. This
+ iterator will return all days (as :class:`datetime.date` objects) for the month
+ and all days before the start of the month or after the end of the month that
+ are required to get a complete week.
+
+
+.. method:: Calendar.itermonthdays2(year, month)
+
+ Return an iterator for the month *month* in the year *year* similar to
+ :meth:`itermonthdates`. Days returned will be tuples consisting of a day number
+ and a week day number.
+
+
+.. method:: Calendar.itermonthdays(year, month)
+
+ Return an iterator for the month *month* in the year *year* similar to
+ :meth:`itermonthdates`. Days returned will simply be day numbers.
+
+
+.. method:: Calendar.monthdatescalendar(year, month)
+
+ Return a list of the weeks in the month *month* of the *year* as full weeks.
+ Weeks are lists of seven :class:`datetime.date` objects.
+
+
+.. method:: Calendar.monthdays2calendar(year, month)
+
+ Return a list of the weeks in the month *month* of the *year* as full weeks.
+ Weeks are lists of seven tuples of day numbers and weekday numbers.
+
+
+.. method:: Calendar.monthdayscalendar(year, month)
+
+ Return a list of the weeks in the month *month* of the *year* as full weeks.
+ Weeks are lists of seven day numbers.
+
+
+.. method:: Calendar.yeardatescalendar(year, month[, width])
+
+ Return the data for the specified year ready for formatting. The return value is
+ a list of month rows. Each month row contains up to *width* months (defaulting
+ to 3). Each month contains between 4 and 6 weeks and each week contains 1--7
+ days. Days are :class:`datetime.date` objects.
+
+
+.. method:: Calendar.yeardays2calendar(year, month[, width])
+
+ Return the data for the specified year ready for formatting (similar to
+ :meth:`yeardatescalendar`). Entries in the week lists are tuples of day numbers
+ and weekday numbers. Day numbers outside this month are zero.
+
+
+.. method:: Calendar.yeardayscalendar(year, month[, width])
+
+ Return the data for the specified year ready for formatting (similar to
+ :meth:`yeardatescalendar`). Entries in the week lists are day numbers. Day
+ numbers outside this month are zero.
+
+
+.. class:: TextCalendar([firstweekday])
+
+ This class can be used to generate plain text calendars.
+
+ .. versionadded:: 2.5
+
+:class:`TextCalendar` instances have the following methods:
+
+
+.. method:: TextCalendar.formatmonth(theyear, themonth[, w[, l]])
+
+ Return a month's calendar in a multi-line string. If *w* is provided, it
+ specifies the width of the date columns, which are centered. If *l* is given, it
+ specifies the number of lines that each week will use. Depends on the first
+ weekday as set by :func:`setfirstweekday`.
+
+
+.. method:: TextCalendar.prmonth(theyear, themonth[, w[, l]])
+
+ Print a month's calendar as returned by :meth:`formatmonth`.
+
+
+.. method:: TextCalendar.formatyear(theyear, themonth[, w[, l[, c[, m]]]])
+
+ Return a *m*-column calendar for an entire year as a multi-line string. Optional
+ parameters *w*, *l*, and *c* are for date column width, lines per week, and
+ number of spaces between month columns, respectively. Depends on the first
+ weekday as set by :meth:`setfirstweekday`. The earliest year for which a
+ calendar can be generated is platform-dependent.
+
+
+.. method:: TextCalendar.pryear(theyear[, w[, l[, c[, m]]]])
+
+ Print the calendar for an entire year as returned by :meth:`formatyear`.
+
+
+.. class:: HTMLCalendar([firstweekday])
+
+ This class can be used to generate HTML calendars.
+
+ .. versionadded:: 2.5
+
+:class:`HTMLCalendar` instances have the following methods:
+
+
+.. method:: HTMLCalendar.formatmonth(theyear, themonth[, withyear])
+
+ Return a month's calendar as an HTML table. If *withyear* is true the year will
+ be included in the header, otherwise just the month name will be used.
+
+
+.. method:: HTMLCalendar.formatyear(theyear, themonth[, width])
+
+ Return a year's calendar as an HTML table. *width* (defaulting to 3) specifies
+ the number of months per row.
+
+
+.. method:: HTMLCalendar.formatyearpage(theyear, themonth[, width[, css[, encoding]]])
+
+ Return a year's calendar as a complete HTML page. *width* (defaulting to 3)
+ specifies the number of months per row. *css* is the name for the cascading
+ style sheet to be used. :const:`None` can be passed if no style sheet should be
+ used. *encoding* specifies the encoding to be used for the output (defaulting to
+ the system default encoding).
+
+
+.. class:: LocaleTextCalendar([firstweekday[, locale]])
+
+ This subclass of :class:`TextCalendar` can be passed a locale name in the
+ constructor and will return month and weekday names in the specified locale. If
+ this locale includes an encoding all strings containing month and weekday names
+ will be returned as unicode.
+
+ .. versionadded:: 2.5
+
+
+.. class:: LocaleHTMLCalendar([firstweekday[, locale]])
+
+ This subclass of :class:`HTMLCalendar` can be passed a locale name in the
+ constructor and will return month and weekday names in the specified locale. If
+ this locale includes an encoding all strings containing month and weekday names
+ will be returned as unicode.
+
+ .. versionadded:: 2.5
+
+For simple text calendars this module provides the following functions.
+
+
+.. function:: setfirstweekday(weekday)
+
+ Sets the weekday (``0`` is Monday, ``6`` is Sunday) to start each week. The
+ values :const:`MONDAY`, :const:`TUESDAY`, :const:`WEDNESDAY`, :const:`THURSDAY`,
+ :const:`FRIDAY`, :const:`SATURDAY`, and :const:`SUNDAY` are provided for
+ convenience. For example, to set the first weekday to Sunday::
+
+ import calendar
+ calendar.setfirstweekday(calendar.SUNDAY)
+
+ .. versionadded:: 2.0
+
+
+.. function:: firstweekday()
+
+ Returns the current setting for the weekday to start each week.
+
+ .. versionadded:: 2.0
+
+
+.. function:: isleap(year)
+
+ Returns :const:`True` if *year* is a leap year, otherwise :const:`False`.
+
+
+.. function:: leapdays(y1, y2)
+
+ Returns the number of leap years in the range from *y1* to *y2* (exclusive),
+ where *y1* and *y2* are years.
+
+ .. versionchanged:: 2.0
+ This function didn't work for ranges spanning a century change in Python
+ 1.5.2.
+
+
+.. function:: weekday(year, month, day)
+
+ Returns the day of the week (``0`` is Monday) for *year* (``1970``--...),
+ *month* (``1``--``12``), *day* (``1``--``31``).
+
+
+.. function:: weekheader(n)
+
+ Return a header containing abbreviated weekday names. *n* specifies the width in
+ characters for one weekday.
+
+
+.. function:: monthrange(year, month)
+
+ Returns weekday of first day of the month and number of days in month, for the
+ specified *year* and *month*.
+
+
+.. function:: monthcalendar(year, month)
+
+ Returns a matrix representing a month's calendar. Each row represents a week;
+ days outside of the month a represented by zeros. Each week begins with Monday
+ unless set by :func:`setfirstweekday`.
+
+
+.. function:: prmonth(theyear, themonth[, w[, l]])
+
+ Prints a month's calendar as returned by :func:`month`.
+
+
+.. function:: month(theyear, themonth[, w[, l]])
+
+ Returns a month's calendar in a multi-line string using the :meth:`formatmonth`
+ of the :class:`TextCalendar` class.
+
+ .. versionadded:: 2.0
+
+
+.. function:: prcal(year[, w[, l[c]]])
+
+ Prints the calendar for an entire year as returned by :func:`calendar`.
+
+
+.. function:: calendar(year[, w[, l[c]]])
+
+ Returns a 3-column calendar for an entire year as a multi-line string using the
+ :meth:`formatyear` of the :class:`TextCalendar` class.
+
+ .. versionadded:: 2.0
+
+
+.. function:: timegm(tuple)
+
+ An unrelated but handy function that takes a time tuple such as returned by the
+ :func:`gmtime` function in the :mod:`time` module, and returns the corresponding
+ Unix timestamp value, assuming an epoch of 1970, and the POSIX encoding. In
+ fact, :func:`time.gmtime` and :func:`timegm` are each others' inverse.
+
+ .. versionadded:: 2.0
+
+The :mod:`calendar` module exports the following data attributes:
+
+
+.. data:: day_name
+
+ An array that represents the days of the week in the current locale.
+
+
+.. data:: day_abbr
+
+ An array that represents the abbreviated days of the week in the current locale.
+
+
+.. data:: month_name
+
+ An array that represents the months of the year in the current locale. This
+ follows normal convention of January being month number 1, so it has a length of
+ 13 and ``month_name[0]`` is the empty string.
+
+
+.. data:: month_abbr
+
+ An array that represents the abbreviated months of the year in the current
+ locale. This follows normal convention of January being month number 1, so it
+ has a length of 13 and ``month_abbr[0]`` is the empty string.
+
+
+.. seealso::
+
+ Module :mod:`datetime`
+ Object-oriented interface to dates and times with similar functionality to the
+ :mod:`time` module.
+
+ Module :mod:`time`
+ Low-level time related functions.
+
diff --git a/Doc/library/carbon.rst b/Doc/library/carbon.rst
new file mode 100644
index 0000000000..ecaf3bb477
--- /dev/null
+++ b/Doc/library/carbon.rst
@@ -0,0 +1,288 @@
+
+.. _toolbox:
+
+*********************
+MacOS Toolbox Modules
+*********************
+
+There are a set of modules that provide interfaces to various MacOS toolboxes.
+If applicable the module will define a number of Python objects for the various
+structures declared by the toolbox, and operations will be implemented as
+methods of the object. Other operations will be implemented as functions in the
+module. Not all operations possible in C will also be possible in Python
+(callbacks are often a problem), and parameters will occasionally be different
+in Python (input and output buffers, especially). All methods and functions
+have a :attr:`__doc__` string describing their arguments and return values, and
+for additional description you are referred to `Inside Macintosh
+<http://developer.apple.com/documentation/macos8/mac8.html>`_ or similar works.
+
+These modules all live in a package called :mod:`Carbon`. Despite that name they
+are not all part of the Carbon framework: CF is really in the CoreFoundation
+framework and Qt is in the QuickTime framework. The normal use pattern is ::
+
+ from Carbon import AE
+
+**Warning!** These modules are not yet documented. If you wish to contribute
+documentation of any of these modules, please get in touch with docs@python.org.
+
+
+:mod:`Carbon.AE` --- Apple Events
+=================================
+
+.. module:: Carbon.AE
+ :platform: Mac
+ :synopsis: Interface to the Apple Events toolbox.
+
+
+
+:mod:`Carbon.AH` --- Apple Help
+===============================
+
+.. module:: Carbon.AH
+ :platform: Mac
+ :synopsis: Interface to the Apple Help manager.
+
+
+
+:mod:`Carbon.App` --- Appearance Manager
+========================================
+
+.. module:: Carbon.App
+ :platform: Mac
+ :synopsis: Interface to the Appearance Manager.
+
+
+
+:mod:`Carbon.CF` --- Core Foundation
+====================================
+
+.. module:: Carbon.CF
+ :platform: Mac
+ :synopsis: Interface to the Core Foundation.
+
+
+The ``CFBase``, ``CFArray``, ``CFData``, ``CFDictionary``, ``CFString`` and
+``CFURL`` objects are supported, some only partially.
+
+
+:mod:`Carbon.CG` --- Core Graphics
+==================================
+
+.. module:: Carbon.CG
+ :platform: Mac
+ :synopsis: Interface to the Component Manager.
+
+
+
+:mod:`Carbon.CarbonEvt` --- Carbon Event Manager
+================================================
+
+.. module:: Carbon.CarbonEvt
+ :platform: Mac
+ :synopsis: Interface to the Carbon Event Manager.
+
+
+
+:mod:`Carbon.Cm` --- Component Manager
+======================================
+
+.. module:: Carbon.Cm
+ :platform: Mac
+ :synopsis: Interface to the Component Manager.
+
+
+
+:mod:`Carbon.Ctl` --- Control Manager
+=====================================
+
+.. module:: Carbon.Ctl
+ :platform: Mac
+ :synopsis: Interface to the Control Manager.
+
+
+
+:mod:`Carbon.Dlg` --- Dialog Manager
+====================================
+
+.. module:: Carbon.Dlg
+ :platform: Mac
+ :synopsis: Interface to the Dialog Manager.
+
+
+
+:mod:`Carbon.Evt` --- Event Manager
+===================================
+
+.. module:: Carbon.Evt
+ :platform: Mac
+ :synopsis: Interface to the classic Event Manager.
+
+
+
+:mod:`Carbon.Fm` --- Font Manager
+=================================
+
+.. module:: Carbon.Fm
+ :platform: Mac
+ :synopsis: Interface to the Font Manager.
+
+
+
+:mod:`Carbon.Folder` --- Folder Manager
+=======================================
+
+.. module:: Carbon.Folder
+ :platform: Mac
+ :synopsis: Interface to the Folder Manager.
+
+
+
+:mod:`Carbon.Help` --- Help Manager
+===================================
+
+.. module:: Carbon.Help
+ :platform: Mac
+ :synopsis: Interface to the Carbon Help Manager.
+
+
+
+:mod:`Carbon.List` --- List Manager
+===================================
+
+.. module:: Carbon.List
+ :platform: Mac
+ :synopsis: Interface to the List Manager.
+
+
+
+:mod:`Carbon.Menu` --- Menu Manager
+===================================
+
+.. module:: Carbon.Menu
+ :platform: Mac
+ :synopsis: Interface to the Menu Manager.
+
+
+
+:mod:`Carbon.Mlte` --- MultiLingual Text Editor
+===============================================
+
+.. module:: Carbon.Mlte
+ :platform: Mac
+ :synopsis: Interface to the MultiLingual Text Editor.
+
+
+
+:mod:`Carbon.Qd` --- QuickDraw
+==============================
+
+.. module:: Carbon.Qd
+ :platform: Mac
+ :synopsis: Interface to the QuickDraw toolbox.
+
+
+
+:mod:`Carbon.Qdoffs` --- QuickDraw Offscreen
+============================================
+
+.. module:: Carbon.Qdoffs
+ :platform: Mac
+ :synopsis: Interface to the QuickDraw Offscreen APIs.
+
+
+
+:mod:`Carbon.Qt` --- QuickTime
+==============================
+
+.. module:: Carbon.Qt
+ :platform: Mac
+ :synopsis: Interface to the QuickTime toolbox.
+
+
+
+:mod:`Carbon.Res` --- Resource Manager and Handles
+==================================================
+
+.. module:: Carbon.Res
+ :platform: Mac
+ :synopsis: Interface to the Resource Manager and Handles.
+
+
+
+:mod:`Carbon.Scrap` --- Scrap Manager
+=====================================
+
+.. module:: Carbon.Scrap
+ :platform: Mac
+ :synopsis: The Scrap Manager provides basic services for implementing cut & paste and
+ clipboard operations.
+
+
+This module is only fully available on MacOS9 and earlier under classic PPC
+MacPython. Very limited functionality is available under Carbon MacPython.
+
+.. index:: single: Scrap Manager
+
+The Scrap Manager supports the simplest form of cut & paste operations on the
+Macintosh. It can be use for both inter- and intra-application clipboard
+operations.
+
+The :mod:`Scrap` module provides low-level access to the functions of the Scrap
+Manager. It contains the following functions:
+
+
+.. function:: InfoScrap()
+
+ Return current information about the scrap. The information is encoded as a
+ tuple containing the fields ``(size, handle, count, state, path)``.
+
+ +----------+---------------------------------------------+
+ | Field | Meaning |
+ +==========+=============================================+
+ | *size* | Size of the scrap in bytes. |
+ +----------+---------------------------------------------+
+ | *handle* | Resource object representing the scrap. |
+ +----------+---------------------------------------------+
+ | *count* | Serial number of the scrap contents. |
+ +----------+---------------------------------------------+
+ | *state* | Integer; positive if in memory, ``0`` if on |
+ | | disk, negative if uninitialized. |
+ +----------+---------------------------------------------+
+ | *path* | Filename of the scrap when stored on disk. |
+ +----------+---------------------------------------------+
+
+
+.. seealso::
+
+ `Scrap Manager <http://developer.apple.com/documentation/mac/MoreToolbox/MoreToolbox-109.html>`_
+ Apple's documentation for the Scrap Manager gives a lot of useful information
+ about using the Scrap Manager in applications.
+
+
+
+:mod:`Carbon.Snd` --- Sound Manager
+===================================
+
+.. module:: Carbon.Snd
+ :platform: Mac
+ :synopsis: Interface to the Sound Manager.
+
+
+
+:mod:`Carbon.TE` --- TextEdit
+=============================
+
+.. module:: Carbon.TE
+ :platform: Mac
+ :synopsis: Interface to TextEdit.
+
+
+
+:mod:`Carbon.Win` --- Window Manager
+====================================
+
+.. module:: Carbon.Win
+ :platform: Mac
+ :synopsis: Interface to the Window Manager.
+
+
diff --git a/Doc/library/cgi.rst b/Doc/library/cgi.rst
new file mode 100644
index 0000000000..29ed5459e3
--- /dev/null
+++ b/Doc/library/cgi.rst
@@ -0,0 +1,558 @@
+
+:mod:`cgi` --- Common Gateway Interface support.
+================================================
+
+.. module:: cgi
+ :synopsis: Helpers for running Python scripts via the Common Gateway Interface.
+
+
+.. index::
+ pair: WWW; server
+ pair: CGI; protocol
+ pair: HTTP; protocol
+ pair: MIME; headers
+ single: URL
+ single: Common Gateway Interface
+
+Support module for Common Gateway Interface (CGI) scripts.
+
+This module defines a number of utilities for use by CGI scripts written in
+Python.
+
+
+Introduction
+------------
+
+.. _cgi-intro:
+
+A CGI script is invoked by an HTTP server, usually to process user input
+submitted through an HTML ``<FORM>`` or ``<ISINDEX>`` element.
+
+Most often, CGI scripts live in the server's special :file:`cgi-bin` directory.
+The HTTP server places all sorts of information about the request (such as the
+client's hostname, the requested URL, the query string, and lots of other
+goodies) in the script's shell environment, executes the script, and sends the
+script's output back to the client.
+
+The script's input is connected to the client too, and sometimes the form data
+is read this way; at other times the form data is passed via the "query string"
+part of the URL. This module is intended to take care of the different cases
+and provide a simpler interface to the Python script. It also provides a number
+of utilities that help in debugging scripts, and the latest addition is support
+for file uploads from a form (if your browser supports it).
+
+The output of a CGI script should consist of two sections, separated by a blank
+line. The first section contains a number of headers, telling the client what
+kind of data is following. Python code to generate a minimal header section
+looks like this::
+
+ print "Content-Type: text/html" # HTML is following
+ print # blank line, end of headers
+
+The second section is usually HTML, which allows the client software to display
+nicely formatted text with header, in-line images, etc. Here's Python code that
+prints a simple piece of HTML::
+
+ print "<TITLE>CGI script output</TITLE>"
+ print "<H1>This is my first CGI script</H1>"
+ print "Hello, world!"
+
+
+.. _using-the-cgi-module:
+
+Using the cgi module
+--------------------
+
+Begin by writing ``import cgi``. Do not use ``from cgi import *`` --- the
+module defines all sorts of names for its own use or for backward compatibility
+that you don't want in your namespace.
+
+When you write a new script, consider adding the line::
+
+ import cgitb; cgitb.enable()
+
+This activates a special exception handler that will display detailed reports in
+the Web browser if any errors occur. If you'd rather not show the guts of your
+program to users of your script, you can have the reports saved to files
+instead, with a line like this::
+
+ import cgitb; cgitb.enable(display=0, logdir="/tmp")
+
+It's very helpful to use this feature during script development. The reports
+produced by :mod:`cgitb` provide information that can save you a lot of time in
+tracking down bugs. You can always remove the ``cgitb`` line later when you
+have tested your script and are confident that it works correctly.
+
+To get at submitted form data, it's best to use the :class:`FieldStorage` class.
+The other classes defined in this module are provided mostly for backward
+compatibility. Instantiate it exactly once, without arguments. This reads the
+form contents from standard input or the environment (depending on the value of
+various environment variables set according to the CGI standard). Since it may
+consume standard input, it should be instantiated only once.
+
+The :class:`FieldStorage` instance can be indexed like a Python dictionary, and
+also supports the standard dictionary methods :meth:`has_key` and :meth:`keys`.
+The built-in :func:`len` is also supported. Form fields containing empty
+strings are ignored and do not appear in the dictionary; to keep such values,
+provide a true value for the optional *keep_blank_values* keyword parameter when
+creating the :class:`FieldStorage` instance.
+
+For instance, the following code (which assumes that the
+:mailheader:`Content-Type` header and blank line have already been printed)
+checks that the fields ``name`` and ``addr`` are both set to a non-empty
+string::
+
+ form = cgi.FieldStorage()
+ if not (form.has_key("name") and form.has_key("addr")):
+ print "<H1>Error</H1>"
+ print "Please fill in the name and addr fields."
+ return
+ print "<p>name:", form["name"].value
+ print "<p>addr:", form["addr"].value
+ ...further form processing here...
+
+Here the fields, accessed through ``form[key]``, are themselves instances of
+:class:`FieldStorage` (or :class:`MiniFieldStorage`, depending on the form
+encoding). The :attr:`value` attribute of the instance yields the string value
+of the field. The :meth:`getvalue` method returns this string value directly;
+it also accepts an optional second argument as a default to return if the
+requested key is not present.
+
+If the submitted form data contains more than one field with the same name, the
+object retrieved by ``form[key]`` is not a :class:`FieldStorage` or
+:class:`MiniFieldStorage` instance but a list of such instances. Similarly, in
+this situation, ``form.getvalue(key)`` would return a list of strings. If you
+expect this possibility (when your HTML form contains multiple fields with the
+same name), use the :func:`getlist` function, which always returns a list of
+values (so that you do not need to special-case the single item case). For
+example, this code concatenates any number of username fields, separated by
+commas::
+
+ value = form.getlist("username")
+ usernames = ",".join(value)
+
+If a field represents an uploaded file, accessing the value via the
+:attr:`value` attribute or the :func:`getvalue` method reads the entire file in
+memory as a string. This may not be what you want. You can test for an uploaded
+file by testing either the :attr:`filename` attribute or the :attr:`file`
+attribute. You can then read the data at leisure from the :attr:`file`
+attribute::
+
+ fileitem = form["userfile"]
+ if fileitem.file:
+ # It's an uploaded file; count lines
+ linecount = 0
+ while 1:
+ line = fileitem.file.readline()
+ if not line: break
+ linecount = linecount + 1
+
+The file upload draft standard entertains the possibility of uploading multiple
+files from one field (using a recursive :mimetype:`multipart/\*` encoding).
+When this occurs, the item will be a dictionary-like :class:`FieldStorage` item.
+This can be determined by testing its :attr:`type` attribute, which should be
+:mimetype:`multipart/form-data` (or perhaps another MIME type matching
+:mimetype:`multipart/\*`). In this case, it can be iterated over recursively
+just like the top-level form object.
+
+When a form is submitted in the "old" format (as the query string or as a single
+data part of type :mimetype:`application/x-www-form-urlencoded`), the items will
+actually be instances of the class :class:`MiniFieldStorage`. In this case, the
+:attr:`list`, :attr:`file`, and :attr:`filename` attributes are always ``None``.
+
+
+Higher Level Interface
+----------------------
+
+.. versionadded:: 2.2
+
+The previous section explains how to read CGI form data using the
+:class:`FieldStorage` class. This section describes a higher level interface
+which was added to this class to allow one to do it in a more readable and
+intuitive way. The interface doesn't make the techniques described in previous
+sections obsolete --- they are still useful to process file uploads efficiently,
+for example.
+
+.. % XXX: Is this true ?
+
+The interface consists of two simple methods. Using the methods you can process
+form data in a generic way, without the need to worry whether only one or more
+values were posted under one name.
+
+In the previous section, you learned to write following code anytime you
+expected a user to post more than one value under one name::
+
+ item = form.getvalue("item")
+ if isinstance(item, list):
+ # The user is requesting more than one item.
+ else:
+ # The user is requesting only one item.
+
+This situation is common for example when a form contains a group of multiple
+checkboxes with the same name::
+
+ <input type="checkbox" name="item" value="1" />
+ <input type="checkbox" name="item" value="2" />
+
+In most situations, however, there's only one form control with a particular
+name in a form and then you expect and need only one value associated with this
+name. So you write a script containing for example this code::
+
+ user = form.getvalue("user").upper()
+
+The problem with the code is that you should never expect that a client will
+provide valid input to your scripts. For example, if a curious user appends
+another ``user=foo`` pair to the query string, then the script would crash,
+because in this situation the ``getvalue("user")`` method call returns a list
+instead of a string. Calling the :meth:`toupper` method on a list is not valid
+(since lists do not have a method of this name) and results in an
+:exc:`AttributeError` exception.
+
+Therefore, the appropriate way to read form data values was to always use the
+code which checks whether the obtained value is a single value or a list of
+values. That's annoying and leads to less readable scripts.
+
+A more convenient approach is to use the methods :meth:`getfirst` and
+:meth:`getlist` provided by this higher level interface.
+
+
+.. method:: FieldStorage.getfirst(name[, default])
+
+ This method always returns only one value associated with form field *name*.
+ The method returns only the first value in case that more values were posted
+ under such name. Please note that the order in which the values are received
+ may vary from browser to browser and should not be counted on. [#]_ If no such
+ form field or value exists then the method returns the value specified by the
+ optional parameter *default*. This parameter defaults to ``None`` if not
+ specified.
+
+
+.. method:: FieldStorage.getlist(name)
+
+ This method always returns a list of values associated with form field *name*.
+ The method returns an empty list if no such form field or value exists for
+ *name*. It returns a list consisting of one item if only one such value exists.
+
+Using these methods you can write nice compact code::
+
+ import cgi
+ form = cgi.FieldStorage()
+ user = form.getfirst("user", "").upper() # This way it's safe.
+ for item in form.getlist("item"):
+ do_something(item)
+
+
+Old classes
+-----------
+
+These classes, present in earlier versions of the :mod:`cgi` module, are still
+supported for backward compatibility. New applications should use the
+:class:`FieldStorage` class.
+
+:class:`SvFormContentDict` stores single value form content as dictionary; it
+assumes each field name occurs in the form only once.
+
+:class:`FormContentDict` stores multiple value form content as a dictionary (the
+form items are lists of values). Useful if your form contains multiple fields
+with the same name.
+
+Other classes (:class:`FormContent`, :class:`InterpFormContentDict`) are present
+for backwards compatibility with really old applications only. If you still use
+these and would be inconvenienced when they disappeared from a next version of
+this module, drop me a note.
+
+
+.. _functions-in-cgi-module:
+
+Functions
+---------
+
+These are useful if you want more control, or if you want to employ some of the
+algorithms implemented in this module in other circumstances.
+
+
+.. function:: parse(fp[, keep_blank_values[, strict_parsing]])
+
+ Parse a query in the environment or from a file (the file defaults to
+ ``sys.stdin``). The *keep_blank_values* and *strict_parsing* parameters are
+ passed to :func:`parse_qs` unchanged.
+
+
+.. function:: parse_qs(qs[, keep_blank_values[, strict_parsing]])
+
+ Parse a query string given as a string argument (data of type
+ :mimetype:`application/x-www-form-urlencoded`). Data are returned as a
+ dictionary. The dictionary keys are the unique query variable names and the
+ values are lists of values for each name.
+
+ The optional argument *keep_blank_values* is a flag indicating whether blank
+ values in URL encoded queries should be treated as blank strings. A true value
+ indicates that blanks should be retained as blank strings. The default false
+ value indicates that blank values are to be ignored and treated as if they were
+ not included.
+
+ The optional argument *strict_parsing* is a flag indicating what to do with
+ parsing errors. If false (the default), errors are silently ignored. If true,
+ errors raise a :exc:`ValueError` exception.
+
+ Use the :func:`urllib.urlencode` function to convert such dictionaries into
+ query strings.
+
+
+.. function:: parse_qsl(qs[, keep_blank_values[, strict_parsing]])
+
+ Parse a query string given as a string argument (data of type
+ :mimetype:`application/x-www-form-urlencoded`). Data are returned as a list of
+ name, value pairs.
+
+ The optional argument *keep_blank_values* is a flag indicating whether blank
+ values in URL encoded queries should be treated as blank strings. A true value
+ indicates that blanks should be retained as blank strings. The default false
+ value indicates that blank values are to be ignored and treated as if they were
+ not included.
+
+ The optional argument *strict_parsing* is a flag indicating what to do with
+ parsing errors. If false (the default), errors are silently ignored. If true,
+ errors raise a :exc:`ValueError` exception.
+
+ Use the :func:`urllib.urlencode` function to convert such lists of pairs into
+ query strings.
+
+
+.. function:: parse_multipart(fp, pdict)
+
+ Parse input of type :mimetype:`multipart/form-data` (for file uploads).
+ Arguments are *fp* for the input file and *pdict* for a dictionary containing
+ other parameters in the :mailheader:`Content-Type` header.
+
+ Returns a dictionary just like :func:`parse_qs` keys are the field names, each
+ value is a list of values for that field. This is easy to use but not much good
+ if you are expecting megabytes to be uploaded --- in that case, use the
+ :class:`FieldStorage` class instead which is much more flexible.
+
+ Note that this does not parse nested multipart parts --- use
+ :class:`FieldStorage` for that.
+
+
+.. function:: parse_header(string)
+
+ Parse a MIME header (such as :mailheader:`Content-Type`) into a main value and a
+ dictionary of parameters.
+
+
+.. function:: test()
+
+ Robust test CGI script, usable as main program. Writes minimal HTTP headers and
+ formats all information provided to the script in HTML form.
+
+
+.. function:: print_environ()
+
+ Format the shell environment in HTML.
+
+
+.. function:: print_form(form)
+
+ Format a form in HTML.
+
+
+.. function:: print_directory()
+
+ Format the current directory in HTML.
+
+
+.. function:: print_environ_usage()
+
+ Print a list of useful (used by CGI) environment variables in HTML.
+
+
+.. function:: escape(s[, quote])
+
+ Convert the characters ``'&'``, ``'<'`` and ``'>'`` in string *s* to HTML-safe
+ sequences. Use this if you need to display text that might contain such
+ characters in HTML. If the optional flag *quote* is true, the quotation mark
+ character (``'"'``) is also translated; this helps for inclusion in an HTML
+ attribute value, as in ``<A HREF="...">``. If the value to be quoted might
+ include single- or double-quote characters, or both, consider using the
+ :func:`quoteattr` function in the :mod:`xml.sax.saxutils` module instead.
+
+
+.. _cgi-security:
+
+Caring about security
+---------------------
+
+.. index:: pair: CGI; security
+
+There's one important rule: if you invoke an external program (via the
+:func:`os.system` or :func:`os.popen` functions. or others with similar
+functionality), make very sure you don't pass arbitrary strings received from
+the client to the shell. This is a well-known security hole whereby clever
+hackers anywhere on the Web can exploit a gullible CGI script to invoke
+arbitrary shell commands. Even parts of the URL or field names cannot be
+trusted, since the request doesn't have to come from your form!
+
+To be on the safe side, if you must pass a string gotten from a form to a shell
+command, you should make sure the string contains only alphanumeric characters,
+dashes, underscores, and periods.
+
+
+Installing your CGI script on a Unix system
+-------------------------------------------
+
+Read the documentation for your HTTP server and check with your local system
+administrator to find the directory where CGI scripts should be installed;
+usually this is in a directory :file:`cgi-bin` in the server tree.
+
+Make sure that your script is readable and executable by "others"; the Unix file
+mode should be ``0755`` octal (use ``chmod 0755 filename``). Make sure that the
+first line of the script contains ``#!`` starting in column 1 followed by the
+pathname of the Python interpreter, for instance::
+
+ #!/usr/local/bin/python
+
+Make sure the Python interpreter exists and is executable by "others".
+
+Make sure that any files your script needs to read or write are readable or
+writable, respectively, by "others" --- their mode should be ``0644`` for
+readable and ``0666`` for writable. This is because, for security reasons, the
+HTTP server executes your script as user "nobody", without any special
+privileges. It can only read (write, execute) files that everybody can read
+(write, execute). The current directory at execution time is also different (it
+is usually the server's cgi-bin directory) and the set of environment variables
+is also different from what you get when you log in. In particular, don't count
+on the shell's search path for executables (:envvar:`PATH`) or the Python module
+search path (:envvar:`PYTHONPATH`) to be set to anything interesting.
+
+If you need to load modules from a directory which is not on Python's default
+module search path, you can change the path in your script, before importing
+other modules. For example::
+
+ import sys
+ sys.path.insert(0, "/usr/home/joe/lib/python")
+ sys.path.insert(0, "/usr/local/lib/python")
+
+(This way, the directory inserted last will be searched first!)
+
+Instructions for non-Unix systems will vary; check your HTTP server's
+documentation (it will usually have a section on CGI scripts).
+
+
+Testing your CGI script
+-----------------------
+
+Unfortunately, a CGI script will generally not run when you try it from the
+command line, and a script that works perfectly from the command line may fail
+mysteriously when run from the server. There's one reason why you should still
+test your script from the command line: if it contains a syntax error, the
+Python interpreter won't execute it at all, and the HTTP server will most likely
+send a cryptic error to the client.
+
+Assuming your script has no syntax errors, yet it does not work, you have no
+choice but to read the next section.
+
+
+Debugging CGI scripts
+---------------------
+
+.. index:: pair: CGI; debugging
+
+First of all, check for trivial installation errors --- reading the section
+above on installing your CGI script carefully can save you a lot of time. If
+you wonder whether you have understood the installation procedure correctly, try
+installing a copy of this module file (:file:`cgi.py`) as a CGI script. When
+invoked as a script, the file will dump its environment and the contents of the
+form in HTML form. Give it the right mode etc, and send it a request. If it's
+installed in the standard :file:`cgi-bin` directory, it should be possible to
+send it a request by entering a URL into your browser of the form::
+
+ http://yourhostname/cgi-bin/cgi.py?name=Joe+Blow&addr=At+Home
+
+If this gives an error of type 404, the server cannot find the script -- perhaps
+you need to install it in a different directory. If it gives another error,
+there's an installation problem that you should fix before trying to go any
+further. If you get a nicely formatted listing of the environment and form
+content (in this example, the fields should be listed as "addr" with value "At
+Home" and "name" with value "Joe Blow"), the :file:`cgi.py` script has been
+installed correctly. If you follow the same procedure for your own script, you
+should now be able to debug it.
+
+The next step could be to call the :mod:`cgi` module's :func:`test` function
+from your script: replace its main code with the single statement ::
+
+ cgi.test()
+
+This should produce the same results as those gotten from installing the
+:file:`cgi.py` file itself.
+
+When an ordinary Python script raises an unhandled exception (for whatever
+reason: of a typo in a module name, a file that can't be opened, etc.), the
+Python interpreter prints a nice traceback and exits. While the Python
+interpreter will still do this when your CGI script raises an exception, most
+likely the traceback will end up in one of the HTTP server's log files, or be
+discarded altogether.
+
+Fortunately, once you have managed to get your script to execute *some* code,
+you can easily send tracebacks to the Web browser using the :mod:`cgitb` module.
+If you haven't done so already, just add the line::
+
+ import cgitb; cgitb.enable()
+
+to the top of your script. Then try running it again; when a problem occurs,
+you should see a detailed report that will likely make apparent the cause of the
+crash.
+
+If you suspect that there may be a problem in importing the :mod:`cgitb` module,
+you can use an even more robust approach (which only uses built-in modules)::
+
+ import sys
+ sys.stderr = sys.stdout
+ print "Content-Type: text/plain"
+ print
+ ...your code here...
+
+This relies on the Python interpreter to print the traceback. The content type
+of the output is set to plain text, which disables all HTML processing. If your
+script works, the raw HTML will be displayed by your client. If it raises an
+exception, most likely after the first two lines have been printed, a traceback
+will be displayed. Because no HTML interpretation is going on, the traceback
+will be readable.
+
+
+Common problems and solutions
+-----------------------------
+
+* Most HTTP servers buffer the output from CGI scripts until the script is
+ completed. This means that it is not possible to display a progress report on
+ the client's display while the script is running.
+
+* Check the installation instructions above.
+
+* Check the HTTP server's log files. (``tail -f logfile`` in a separate window
+ may be useful!)
+
+* Always check a script for syntax errors first, by doing something like
+ ``python script.py``.
+
+* If your script does not have any syntax errors, try adding ``import cgitb;
+ cgitb.enable()`` to the top of the script.
+
+* When invoking external programs, make sure they can be found. Usually, this
+ means using absolute path names --- :envvar:`PATH` is usually not set to a very
+ useful value in a CGI script.
+
+* When reading or writing external files, make sure they can be read or written
+ by the userid under which your CGI script will be running: this is typically the
+ userid under which the web server is running, or some explicitly specified
+ userid for a web server's ``suexec`` feature.
+
+* Don't try to give a CGI script a set-uid mode. This doesn't work on most
+ systems, and is a security liability as well.
+
+.. rubric:: Footnotes
+
+.. [#] Note that some recent versions of the HTML specification do state what order the
+ field values should be supplied in, but knowing whether a request was
+ received from a conforming browser, or even from a browser at all, is tedious
+ and error-prone.
+
diff --git a/Doc/library/cgihttpserver.rst b/Doc/library/cgihttpserver.rst
new file mode 100644
index 0000000000..4f27627e23
--- /dev/null
+++ b/Doc/library/cgihttpserver.rst
@@ -0,0 +1,73 @@
+
+:mod:`CGIHTTPServer` --- CGI-capable HTTP request handler
+=========================================================
+
+.. module:: CGIHTTPServer
+ :synopsis: This module provides a request handler for HTTP servers which can run CGI
+ scripts.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`CGIHTTPServer` module defines a request-handler class, interface
+compatible with :class:`BaseHTTPServer.BaseHTTPRequestHandler` and inherits
+behavior from :class:`SimpleHTTPServer.SimpleHTTPRequestHandler` but can also
+run CGI scripts.
+
+.. note::
+
+ This module can run CGI scripts on Unix and Windows systems; on Mac OS it will
+ only be able to run Python scripts within the same process as itself.
+
+.. note::
+
+ CGI scripts run by the :class:`CGIHTTPRequestHandler` class cannot execute
+ redirects (HTTP code 302), because code 200 (script output follows) is sent
+ prior to execution of the CGI script. This pre-empts the status code.
+
+The :mod:`CGIHTTPServer` module defines the following class:
+
+
+.. class:: CGIHTTPRequestHandler(request, client_address, server)
+
+ This class is used to serve either files or output of CGI scripts from the
+ current directory and below. Note that mapping HTTP hierarchic structure to
+ local directory structure is exactly as in
+ :class:`SimpleHTTPServer.SimpleHTTPRequestHandler`.
+
+ The class will however, run the CGI script, instead of serving it as a file, if
+ it guesses it to be a CGI script. Only directory-based CGI are used --- the
+ other common server configuration is to treat special extensions as denoting CGI
+ scripts.
+
+ The :func:`do_GET` and :func:`do_HEAD` functions are modified to run CGI scripts
+ and serve the output, instead of serving files, if the request leads to
+ somewhere below the ``cgi_directories`` path.
+
+The :class:`CGIHTTPRequestHandler` defines the following data member:
+
+
+.. attribute:: CGIHTTPRequestHandler.cgi_directories
+
+ This defaults to ``['/cgi-bin', '/htbin']`` and describes directories to treat
+ as containing CGI scripts.
+
+The :class:`CGIHTTPRequestHandler` defines the following methods:
+
+
+.. method:: CGIHTTPRequestHandler.do_POST()
+
+ This method serves the ``'POST'`` request type, only allowed for CGI scripts.
+ Error 501, "Can only POST to CGI scripts", is output when trying to POST to a
+ non-CGI url.
+
+Note that CGI scripts will be run with UID of user nobody, for security reasons.
+Problems with the CGI script will be translated to error 403.
+
+For example usage, see the implementation of the :func:`test` function.
+
+
+.. seealso::
+
+ Module :mod:`BaseHTTPServer`
+ Base class implementation for Web server and request handler.
+
diff --git a/Doc/library/cgitb.rst b/Doc/library/cgitb.rst
new file mode 100644
index 0000000000..327cd17a25
--- /dev/null
+++ b/Doc/library/cgitb.rst
@@ -0,0 +1,64 @@
+
+:mod:`cgitb` --- Traceback manager for CGI scripts
+==================================================
+
+.. module:: cgitb
+ :synopsis: Configurable traceback handler for CGI scripts.
+.. moduleauthor:: Ka-Ping Yee <ping@lfw.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. versionadded:: 2.2
+
+.. index::
+ single: CGI; exceptions
+ single: CGI; tracebacks
+ single: exceptions; in CGI scripts
+ single: tracebacks; in CGI scripts
+
+The :mod:`cgitb` module provides a special exception handler for Python scripts.
+(Its name is a bit misleading. It was originally designed to display extensive
+traceback information in HTML for CGI scripts. It was later generalized to also
+display this information in plain text.) After this module is activated, if an
+uncaught exception occurs, a detailed, formatted report will be displayed. The
+report includes a traceback showing excerpts of the source code for each level,
+as well as the values of the arguments and local variables to currently running
+functions, to help you debug the problem. Optionally, you can save this
+information to a file instead of sending it to the browser.
+
+To enable this feature, simply add one line to the top of your CGI script::
+
+ import cgitb; cgitb.enable()
+
+The options to the :func:`enable` function control whether the report is
+displayed in the browser and whether the report is logged to a file for later
+analysis.
+
+
+.. function:: enable([display[, logdir[, context[, format]]]])
+
+ .. index:: single: excepthook() (in module sys)
+
+ This function causes the :mod:`cgitb` module to take over the interpreter's
+ default handling for exceptions by setting the value of :attr:`sys.excepthook`.
+
+ The optional argument *display* defaults to ``1`` and can be set to ``0`` to
+ suppress sending the traceback to the browser. If the argument *logdir* is
+ present, the traceback reports are written to files. The value of *logdir*
+ should be a directory where these files will be placed. The optional argument
+ *context* is the number of lines of context to display around the current line
+ of source code in the traceback; this defaults to ``5``. If the optional
+ argument *format* is ``"html"``, the output is formatted as HTML. Any other
+ value forces plain text output. The default value is ``"html"``.
+
+
+.. function:: handler([info])
+
+ This function handles an exception using the default settings (that is, show a
+ report in the browser, but don't log to a file). This can be used when you've
+ caught an exception and want to report it using :mod:`cgitb`. The optional
+ *info* argument should be a 3-tuple containing an exception type, exception
+ value, and traceback object, exactly like the tuple returned by
+ :func:`sys.exc_info`. If the *info* argument is not supplied, the current
+ exception is obtained from :func:`sys.exc_info`.
+
diff --git a/Doc/library/chunk.rst b/Doc/library/chunk.rst
new file mode 100644
index 0000000000..2e1798d429
--- /dev/null
+++ b/Doc/library/chunk.rst
@@ -0,0 +1,130 @@
+
+:mod:`chunk` --- Read IFF chunked data
+======================================
+
+.. module:: chunk
+ :synopsis: Module to read IFF chunks.
+.. moduleauthor:: Sjoerd Mullender <sjoerd@acm.org>
+.. sectionauthor:: Sjoerd Mullender <sjoerd@acm.org>
+
+
+.. index::
+ single: Audio Interchange File Format
+ single: AIFF
+ single: AIFF-C
+ single: Real Media File Format
+ single: RMFF
+
+This module provides an interface for reading files that use EA IFF 85 chunks.
+[#]_ This format is used in at least the Audio Interchange File Format
+(AIFF/AIFF-C) and the Real Media File Format (RMFF). The WAVE audio file format
+is closely related and can also be read using this module.
+
+A chunk has the following structure:
+
++---------+--------+-------------------------------+
+| Offset | Length | Contents |
++=========+========+===============================+
+| 0 | 4 | Chunk ID |
++---------+--------+-------------------------------+
+| 4 | 4 | Size of chunk in big-endian |
+| | | byte order, not including the |
+| | | header |
++---------+--------+-------------------------------+
+| 8 | *n* | Data bytes, where *n* is the |
+| | | size given in the preceding |
+| | | field |
++---------+--------+-------------------------------+
+| 8 + *n* | 0 or 1 | Pad byte needed if *n* is odd |
+| | | and chunk alignment is used |
++---------+--------+-------------------------------+
+
+The ID is a 4-byte string which identifies the type of chunk.
+
+The size field (a 32-bit value, encoded using big-endian byte order) gives the
+size of the chunk data, not including the 8-byte header.
+
+Usually an IFF-type file consists of one or more chunks. The proposed usage of
+the :class:`Chunk` class defined here is to instantiate an instance at the start
+of each chunk and read from the instance until it reaches the end, after which a
+new instance can be instantiated. At the end of the file, creating a new
+instance will fail with a :exc:`EOFError` exception.
+
+
+.. class:: Chunk(file[, align, bigendian, inclheader])
+
+ Class which represents a chunk. The *file* argument is expected to be a
+ file-like object. An instance of this class is specifically allowed. The
+ only method that is needed is :meth:`read`. If the methods :meth:`seek` and
+ :meth:`tell` are present and don't raise an exception, they are also used.
+ If these methods are present and raise an exception, they are expected to not
+ have altered the object. If the optional argument *align* is true, chunks
+ are assumed to be aligned on 2-byte boundaries. If *align* is false, no
+ alignment is assumed. The default value is true. If the optional argument
+ *bigendian* is false, the chunk size is assumed to be in little-endian order.
+ This is needed for WAVE audio files. The default value is true. If the
+ optional argument *inclheader* is true, the size given in the chunk header
+ includes the size of the header. The default value is false.
+
+A :class:`Chunk` object supports the following methods:
+
+
+.. method:: Chunk.getname()
+
+ Returns the name (ID) of the chunk. This is the first 4 bytes of the chunk.
+
+
+.. method:: Chunk.getsize()
+
+ Returns the size of the chunk.
+
+
+.. method:: Chunk.close()
+
+ Close and skip to the end of the chunk. This does not close the underlying
+ file.
+
+The remaining methods will raise :exc:`IOError` if called after the
+:meth:`close` method has been called.
+
+
+.. method:: Chunk.isatty()
+
+ Returns ``False``.
+
+
+.. method:: Chunk.seek(pos[, whence])
+
+ Set the chunk's current position. The *whence* argument is optional and
+ defaults to ``0`` (absolute file positioning); other values are ``1`` (seek
+ relative to the current position) and ``2`` (seek relative to the file's end).
+ There is no return value. If the underlying file does not allow seek, only
+ forward seeks are allowed.
+
+
+.. method:: Chunk.tell()
+
+ Return the current position into the chunk.
+
+
+.. method:: Chunk.read([size])
+
+ Read at most *size* bytes from the chunk (less if the read hits the end of the
+ chunk before obtaining *size* bytes). If the *size* argument is negative or
+ omitted, read all data until the end of the chunk. The bytes are returned as a
+ string object. An empty string is returned when the end of the chunk is
+ encountered immediately.
+
+
+.. method:: Chunk.skip()
+
+ Skip to the end of the chunk. All further calls to :meth:`read` for the chunk
+ will return ``''``. If you are not interested in the contents of the chunk,
+ this method should be called so that the file points to the start of the next
+ chunk.
+
+.. rubric:: Footnotes
+
+.. [#] "EA IFF 85" Standard for Interchange Format Files, Jerry Morrison, Electronic
+ Arts, January 1985.
+
diff --git a/Doc/library/cmath.rst b/Doc/library/cmath.rst
new file mode 100644
index 0000000000..2bc162c3f4
--- /dev/null
+++ b/Doc/library/cmath.rst
@@ -0,0 +1,156 @@
+
+:mod:`cmath` --- Mathematical functions for complex numbers
+===========================================================
+
+.. module:: cmath
+ :synopsis: Mathematical functions for complex numbers.
+
+
+This module is always available. It provides access to mathematical functions
+for complex numbers. The functions in this module accept integers,
+floating-point numbers or complex numbers as arguments. They will also accept
+any Python object that has either a :meth:`__complex__` or a :meth:`__float__`
+method: these methods are used to convert the object to a complex or
+floating-point number, respectively, and the function is then applied to the
+result of the conversion.
+
+The functions are:
+
+
+.. function:: acos(x)
+
+ Return the arc cosine of *x*. There are two branch cuts: One extends right from
+ 1 along the real axis to ∞, continuous from below. The other extends left from
+ -1 along the real axis to -∞, continuous from above.
+
+
+.. function:: acosh(x)
+
+ Return the hyperbolic arc cosine of *x*. There is one branch cut, extending left
+ from 1 along the real axis to -∞, continuous from above.
+
+
+.. function:: asin(x)
+
+ Return the arc sine of *x*. This has the same branch cuts as :func:`acos`.
+
+
+.. function:: asinh(x)
+
+ Return the hyperbolic arc sine of *x*. There are two branch cuts, extending
+ left from ``±1j`` to ``±∞j``, both continuous from above. These branch cuts
+ should be considered a bug to be corrected in a future release. The correct
+ branch cuts should extend along the imaginary axis, one from ``1j`` up to
+ ``∞j`` and continuous from the right, and one from ``-1j`` down to ``-∞j``
+ and continuous from the left.
+
+
+.. function:: atan(x)
+
+ Return the arc tangent of *x*. There are two branch cuts: One extends from
+ ``1j`` along the imaginary axis to ``∞j``, continuous from the left. The
+ other extends from ``-1j`` along the imaginary axis to ``-∞j``, continuous
+ from the left. (This should probably be changed so the upper cut becomes
+ continuous from the other side.)
+
+
+.. function:: atanh(x)
+
+ Return the hyperbolic arc tangent of *x*. There are two branch cuts: One
+ extends from ``1`` along the real axis to ``∞``, continuous from above. The
+ other extends from ``-1`` along the real axis to ``-∞``, continuous from
+ above. (This should probably be changed so the right cut becomes continuous
+ from the other side.)
+
+
+.. function:: cos(x)
+
+ Return the cosine of *x*.
+
+
+.. function:: cosh(x)
+
+ Return the hyperbolic cosine of *x*.
+
+
+.. function:: exp(x)
+
+ Return the exponential value ``e**x``.
+
+
+.. function:: log(x[, base])
+
+ Returns the logarithm of *x* to the given *base*. If the *base* is not
+ specified, returns the natural logarithm of *x*. There is one branch cut, from 0
+ along the negative real axis to -∞, continuous from above.
+
+ .. versionchanged:: 2.4
+ *base* argument added.
+
+
+.. function:: log10(x)
+
+ Return the base-10 logarithm of *x*. This has the same branch cut as
+ :func:`log`.
+
+
+.. function:: sin(x)
+
+ Return the sine of *x*.
+
+
+.. function:: sinh(x)
+
+ Return the hyperbolic sine of *x*.
+
+
+.. function:: sqrt(x)
+
+ Return the square root of *x*. This has the same branch cut as :func:`log`.
+
+
+.. function:: tan(x)
+
+ Return the tangent of *x*.
+
+
+.. function:: tanh(x)
+
+ Return the hyperbolic tangent of *x*.
+
+The module also defines two mathematical constants:
+
+
+.. data:: pi
+
+ The mathematical constant *pi*, as a float.
+
+
+.. data:: e
+
+ The mathematical constant *e*, as a float.
+
+.. index:: module: math
+
+Note that the selection of functions is similar, but not identical, to that in
+module :mod:`math`. The reason for having two modules is that some users aren't
+interested in complex numbers, and perhaps don't even know what they are. They
+would rather have ``math.sqrt(-1)`` raise an exception than return a complex
+number. Also note that the functions defined in :mod:`cmath` always return a
+complex number, even if the answer can be expressed as a real number (in which
+case the complex number has an imaginary part of zero).
+
+A note on branch cuts: They are curves along which the given function fails to
+be continuous. They are a necessary feature of many complex functions. It is
+assumed that if you need to compute with complex functions, you will understand
+about branch cuts. Consult almost any (not too elementary) book on complex
+variables for enlightenment. For information of the proper choice of branch
+cuts for numerical purposes, a good reference should be the following:
+
+
+.. seealso::
+
+ Kahan, W: Branch cuts for complex elementary functions; or, Much ado about
+ nothing's sign bit. In Iserles, A., and Powell, M. (eds.), The state of the art
+ in numerical analysis. Clarendon Press (1987) pp165-211.
+
diff --git a/Doc/library/cmd.rst b/Doc/library/cmd.rst
new file mode 100644
index 0000000000..9af08e2708
--- /dev/null
+++ b/Doc/library/cmd.rst
@@ -0,0 +1,202 @@
+
+:mod:`cmd` --- Support for line-oriented command interpreters
+=============================================================
+
+.. module:: cmd
+ :synopsis: Build line-oriented command interpreters.
+.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+
+
+The :class:`Cmd` class provides a simple framework for writing line-oriented
+command interpreters. These are often useful for test harnesses, administrative
+tools, and prototypes that will later be wrapped in a more sophisticated
+interface.
+
+
+.. class:: Cmd([completekey[, stdin[, stdout]]])
+
+ A :class:`Cmd` instance or subclass instance is a line-oriented interpreter
+ framework. There is no good reason to instantiate :class:`Cmd` itself; rather,
+ it's useful as a superclass of an interpreter class you define yourself in order
+ to inherit :class:`Cmd`'s methods and encapsulate action methods.
+
+ The optional argument *completekey* is the :mod:`readline` name of a completion
+ key; it defaults to :kbd:`Tab`. If *completekey* is not :const:`None` and
+ :mod:`readline` is available, command completion is done automatically.
+
+ The optional arguments *stdin* and *stdout* specify the input and output file
+ objects that the Cmd instance or subclass instance will use for input and
+ output. If not specified, they will default to *sys.stdin* and *sys.stdout*.
+
+ .. versionchanged:: 2.3
+ The *stdin* and *stdout* parameters were added.
+
+
+.. _cmd-objects:
+
+Cmd Objects
+-----------
+
+A :class:`Cmd` instance has the following methods:
+
+
+.. method:: Cmd.cmdloop([intro])
+
+ Repeatedly issue a prompt, accept input, parse an initial prefix off the
+ received input, and dispatch to action methods, passing them the remainder of
+ the line as argument.
+
+ The optional argument is a banner or intro string to be issued before the first
+ prompt (this overrides the :attr:`intro` class member).
+
+ If the :mod:`readline` module is loaded, input will automatically inherit
+ :program:`bash`\ -like history-list editing (e.g. :kbd:`Control-P` scrolls back
+ to the last command, :kbd:`Control-N` forward to the next one, :kbd:`Control-F`
+ moves the cursor to the right non-destructively, :kbd:`Control-B` moves the
+ cursor to the left non-destructively, etc.).
+
+ An end-of-file on input is passed back as the string ``'EOF'``.
+
+ An interpreter instance will recognize a command name ``foo`` if and only if it
+ has a method :meth:`do_foo`. As a special case, a line beginning with the
+ character ``'?'`` is dispatched to the method :meth:`do_help`. As another
+ special case, a line beginning with the character ``'!'`` is dispatched to the
+ method :meth:`do_shell` (if such a method is defined).
+
+ This method will return when the :meth:`postcmd` method returns a true value.
+ The *stop* argument to :meth:`postcmd` is the return value from the command's
+ corresponding :meth:`do_\*` method.
+
+ If completion is enabled, completing commands will be done automatically, and
+ completing of commands args is done by calling :meth:`complete_foo` with
+ arguments *text*, *line*, *begidx*, and *endidx*. *text* is the string prefix
+ we are attempting to match: all returned matches must begin with it. *line* is
+ the current input line with leading whitespace removed, *begidx* and *endidx*
+ are the beginning and ending indexes of the prefix text, which could be used to
+ provide different completion depending upon which position the argument is in.
+
+ All subclasses of :class:`Cmd` inherit a predefined :meth:`do_help`. This
+ method, called with an argument ``'bar'``, invokes the corresponding method
+ :meth:`help_bar`. With no argument, :meth:`do_help` lists all available help
+ topics (that is, all commands with corresponding :meth:`help_\*` methods), and
+ also lists any undocumented commands.
+
+
+.. method:: Cmd.onecmd(str)
+
+ Interpret the argument as though it had been typed in response to the prompt.
+ This may be overridden, but should not normally need to be; see the
+ :meth:`precmd` and :meth:`postcmd` methods for useful execution hooks. The
+ return value is a flag indicating whether interpretation of commands by the
+ interpreter should stop. If there is a :meth:`do_\*` method for the command
+ *str*, the return value of that method is returned, otherwise the return value
+ from the :meth:`default` method is returned.
+
+
+.. method:: Cmd.emptyline()
+
+ Method called when an empty line is entered in response to the prompt. If this
+ method is not overridden, it repeats the last nonempty command entered.
+
+
+.. method:: Cmd.default(line)
+
+ Method called on an input line when the command prefix is not recognized. If
+ this method is not overridden, it prints an error message and returns.
+
+
+.. method:: Cmd.completedefault(text, line, begidx, endidx)
+
+ Method called to complete an input line when no command-specific
+ :meth:`complete_\*` method is available. By default, it returns an empty list.
+
+
+.. method:: Cmd.precmd(line)
+
+ Hook method executed just before the command line *line* is interpreted, but
+ after the input prompt is generated and issued. This method is a stub in
+ :class:`Cmd`; it exists to be overridden by subclasses. The return value is
+ used as the command which will be executed by the :meth:`onecmd` method; the
+ :meth:`precmd` implementation may re-write the command or simply return *line*
+ unchanged.
+
+
+.. method:: Cmd.postcmd(stop, line)
+
+ Hook method executed just after a command dispatch is finished. This method is
+ a stub in :class:`Cmd`; it exists to be overridden by subclasses. *line* is the
+ command line which was executed, and *stop* is a flag which indicates whether
+ execution will be terminated after the call to :meth:`postcmd`; this will be the
+ return value of the :meth:`onecmd` method. The return value of this method will
+ be used as the new value for the internal flag which corresponds to *stop*;
+ returning false will cause interpretation to continue.
+
+
+.. method:: Cmd.preloop()
+
+ Hook method executed once when :meth:`cmdloop` is called. This method is a stub
+ in :class:`Cmd`; it exists to be overridden by subclasses.
+
+
+.. method:: Cmd.postloop()
+
+ Hook method executed once when :meth:`cmdloop` is about to return. This method
+ is a stub in :class:`Cmd`; it exists to be overridden by subclasses.
+
+Instances of :class:`Cmd` subclasses have some public instance variables:
+
+
+.. attribute:: Cmd.prompt
+
+ The prompt issued to solicit input.
+
+
+.. attribute:: Cmd.identchars
+
+ The string of characters accepted for the command prefix.
+
+
+.. attribute:: Cmd.lastcmd
+
+ The last nonempty command prefix seen.
+
+
+.. attribute:: Cmd.intro
+
+ A string to issue as an intro or banner. May be overridden by giving the
+ :meth:`cmdloop` method an argument.
+
+
+.. attribute:: Cmd.doc_header
+
+ The header to issue if the help output has a section for documented commands.
+
+
+.. attribute:: Cmd.misc_header
+
+ The header to issue if the help output has a section for miscellaneous help
+ topics (that is, there are :meth:`help_\*` methods without corresponding
+ :meth:`do_\*` methods).
+
+
+.. attribute:: Cmd.undoc_header
+
+ The header to issue if the help output has a section for undocumented commands
+ (that is, there are :meth:`do_\*` methods without corresponding :meth:`help_\*`
+ methods).
+
+
+.. attribute:: Cmd.ruler
+
+ The character used to draw separator lines under the help-message headers. If
+ empty, no ruler line is drawn. It defaults to ``'='``.
+
+
+.. attribute:: Cmd.use_rawinput
+
+ A flag, defaulting to true. If true, :meth:`cmdloop` uses :func:`input` to
+ display a prompt and read the next command; if false, :meth:`sys.stdout.write`
+ and :meth:`sys.stdin.readline` are used. (This means that by importing
+ :mod:`readline`, on systems that support it, the interpreter will automatically
+ support :program:`Emacs`\ -like line editing and command-history keystrokes.)
+
diff --git a/Doc/library/code.rst b/Doc/library/code.rst
new file mode 100644
index 0000000000..4e00639027
--- /dev/null
+++ b/Doc/library/code.rst
@@ -0,0 +1,167 @@
+
+:mod:`code` --- Interpreter base classes
+========================================
+
+.. module:: code
+ :synopsis: Facilities to implement read-eval-print loops.
+
+
+
+The ``code`` module provides facilities to implement read-eval-print loops in
+Python. Two classes and convenience functions are included which can be used to
+build applications which provide an interactive interpreter prompt.
+
+
+.. class:: InteractiveInterpreter([locals])
+
+ This class deals with parsing and interpreter state (the user's namespace); it
+ does not deal with input buffering or prompting or input file naming (the
+ filename is always passed in explicitly). The optional *locals* argument
+ specifies the dictionary in which code will be executed; it defaults to a newly
+ created dictionary with key ``'__name__'`` set to ``'__console__'`` and key
+ ``'__doc__'`` set to ``None``.
+
+
+.. class:: InteractiveConsole([locals[, filename]])
+
+ Closely emulate the behavior of the interactive Python interpreter. This class
+ builds on :class:`InteractiveInterpreter` and adds prompting using the familiar
+ ``sys.ps1`` and ``sys.ps2``, and input buffering.
+
+
+.. function:: interact([banner[, readfunc[, local]]])
+
+ Convenience function to run a read-eval-print loop. This creates a new instance
+ of :class:`InteractiveConsole` and sets *readfunc* to be used as the
+ :meth:`raw_input` method, if provided. If *local* is provided, it is passed to
+ the :class:`InteractiveConsole` constructor for use as the default namespace for
+ the interpreter loop. The :meth:`interact` method of the instance is then run
+ with *banner* passed as the banner to use, if provided. The console object is
+ discarded after use.
+
+
+.. function:: compile_command(source[, filename[, symbol]])
+
+ This function is useful for programs that want to emulate Python's interpreter
+ main loop (a.k.a. the read-eval-print loop). The tricky part is to determine
+ when the user has entered an incomplete command that can be completed by
+ entering more text (as opposed to a complete command or a syntax error). This
+ function *almost* always makes the same decision as the real interpreter main
+ loop.
+
+ *source* is the source string; *filename* is the optional filename from which
+ source was read, defaulting to ``'<input>'``; and *symbol* is the optional
+ grammar start symbol, which should be either ``'single'`` (the default) or
+ ``'eval'``.
+
+ Returns a code object (the same as ``compile(source, filename, symbol)``) if the
+ command is complete and valid; ``None`` if the command is incomplete; raises
+ :exc:`SyntaxError` if the command is complete and contains a syntax error, or
+ raises :exc:`OverflowError` or :exc:`ValueError` if the command contains an
+ invalid literal.
+
+
+.. _interpreter-objects:
+
+Interactive Interpreter Objects
+-------------------------------
+
+
+.. method:: InteractiveInterpreter.runsource(source[, filename[, symbol]])
+
+ Compile and run some source in the interpreter. Arguments are the same as for
+ :func:`compile_command`; the default for *filename* is ``'<input>'``, and for
+ *symbol* is ``'single'``. One several things can happen:
+
+ * The input is incorrect; :func:`compile_command` raised an exception
+ (:exc:`SyntaxError` or :exc:`OverflowError`). A syntax traceback will be
+ printed by calling the :meth:`showsyntaxerror` method. :meth:`runsource`
+ returns ``False``.
+
+ * The input is incomplete, and more input is required; :func:`compile_command`
+ returned ``None``. :meth:`runsource` returns ``True``.
+
+ * The input is complete; :func:`compile_command` returned a code object. The
+ code is executed by calling the :meth:`runcode` (which also handles run-time
+ exceptions, except for :exc:`SystemExit`). :meth:`runsource` returns ``False``.
+
+ The return value can be used to decide whether to use ``sys.ps1`` or ``sys.ps2``
+ to prompt the next line.
+
+
+.. method:: InteractiveInterpreter.runcode(code)
+
+ Execute a code object. When an exception occurs, :meth:`showtraceback` is called
+ to display a traceback. All exceptions are caught except :exc:`SystemExit`,
+ which is allowed to propagate.
+
+ A note about :exc:`KeyboardInterrupt`: this exception may occur elsewhere in
+ this code, and may not always be caught. The caller should be prepared to deal
+ with it.
+
+
+.. method:: InteractiveInterpreter.showsyntaxerror([filename])
+
+ Display the syntax error that just occurred. This does not display a stack
+ trace because there isn't one for syntax errors. If *filename* is given, it is
+ stuffed into the exception instead of the default filename provided by Python's
+ parser, because it always uses ``'<string>'`` when reading from a string. The
+ output is written by the :meth:`write` method.
+
+
+.. method:: InteractiveInterpreter.showtraceback()
+
+ Display the exception that just occurred. We remove the first stack item
+ because it is within the interpreter object implementation. The output is
+ written by the :meth:`write` method.
+
+
+.. method:: InteractiveInterpreter.write(data)
+
+ Write a string to the standard error stream (``sys.stderr``). Derived classes
+ should override this to provide the appropriate output handling as needed.
+
+
+.. _console-objects:
+
+Interactive Console Objects
+---------------------------
+
+The :class:`InteractiveConsole` class is a subclass of
+:class:`InteractiveInterpreter`, and so offers all the methods of the
+interpreter objects as well as the following additions.
+
+
+.. method:: InteractiveConsole.interact([banner])
+
+ Closely emulate the interactive Python console. The optional banner argument
+ specify the banner to print before the first interaction; by default it prints a
+ banner similar to the one printed by the standard Python interpreter, followed
+ by the class name of the console object in parentheses (so as not to confuse
+ this with the real interpreter -- since it's so close!).
+
+
+.. method:: InteractiveConsole.push(line)
+
+ Push a line of source text to the interpreter. The line should not have a
+ trailing newline; it may have internal newlines. The line is appended to a
+ buffer and the interpreter's :meth:`runsource` method is called with the
+ concatenated contents of the buffer as source. If this indicates that the
+ command was executed or invalid, the buffer is reset; otherwise, the command is
+ incomplete, and the buffer is left as it was after the line was appended. The
+ return value is ``True`` if more input is required, ``False`` if the line was
+ dealt with in some way (this is the same as :meth:`runsource`).
+
+
+.. method:: InteractiveConsole.resetbuffer()
+
+ Remove any unhandled source text from the input buffer.
+
+
+.. method:: InteractiveConsole.raw_input([prompt])
+
+ Write a prompt and read a line. The returned line does not include the trailing
+ newline. When the user enters the EOF key sequence, :exc:`EOFError` is raised.
+ The base implementation reads from ``sys.stdin``; a subclass may replace this
+ with a different implementation.
+
diff --git a/Doc/library/codecs.rst b/Doc/library/codecs.rst
new file mode 100644
index 0000000000..38264dfdf9
--- /dev/null
+++ b/Doc/library/codecs.rst
@@ -0,0 +1,1230 @@
+
+:mod:`codecs` --- Codec registry and base classes
+=================================================
+
+.. module:: codecs
+ :synopsis: Encode and decode data and streams.
+.. moduleauthor:: Marc-Andre Lemburg <mal@lemburg.com>
+.. sectionauthor:: Marc-Andre Lemburg <mal@lemburg.com>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. index::
+ single: Unicode
+ single: Codecs
+ pair: Codecs; encode
+ pair: Codecs; decode
+ single: streams
+ pair: stackable; streams
+
+This module defines base classes for standard Python codecs (encoders and
+decoders) and provides access to the internal Python codec registry which
+manages the codec and error handling lookup process.
+
+It defines the following functions:
+
+
+.. function:: register(search_function)
+
+ Register a codec search function. Search functions are expected to take one
+ argument, the encoding name in all lower case letters, and return a
+ :class:`CodecInfo` object having the following attributes:
+
+ * ``name`` The name of the encoding;
+
+ * ``encoder`` The stateless encoding function;
+
+ * ``decoder`` The stateless decoding function;
+
+ * ``incrementalencoder`` An incremental encoder class or factory function;
+
+ * ``incrementaldecoder`` An incremental decoder class or factory function;
+
+ * ``streamwriter`` A stream writer class or factory function;
+
+ * ``streamreader`` A stream reader class or factory function.
+
+ The various functions or classes take the following arguments:
+
+ *encoder* and *decoder*: These must be functions or methods which have the same
+ interface as the :meth:`encode`/:meth:`decode` methods of Codec instances (see
+ Codec Interface). The functions/methods are expected to work in a stateless
+ mode.
+
+ *incrementalencoder* and *incrementalencoder*: These have to be factory
+ functions providing the following interface:
+
+ ``factory(errors='strict')``
+
+ The factory functions must return objects providing the interfaces defined by
+ the base classes :class:`IncrementalEncoder` and :class:`IncrementalEncoder`,
+ respectively. Incremental codecs can maintain state.
+
+ *streamreader* and *streamwriter*: These have to be factory functions providing
+ the following interface:
+
+ ``factory(stream, errors='strict')``
+
+ The factory functions must return objects providing the interfaces defined by
+ the base classes :class:`StreamWriter` and :class:`StreamReader`, respectively.
+ Stream codecs can maintain state.
+
+ Possible values for errors are ``'strict'`` (raise an exception in case of an
+ encoding error), ``'replace'`` (replace malformed data with a suitable
+ replacement marker, such as ``'?'``), ``'ignore'`` (ignore malformed data and
+ continue without further notice), ``'xmlcharrefreplace'`` (replace with the
+ appropriate XML character reference (for encoding only)) and
+ ``'backslashreplace'`` (replace with backslashed escape sequences (for encoding
+ only)) as well as any other error handling name defined via
+ :func:`register_error`.
+
+ In case a search function cannot find a given encoding, it should return
+ ``None``.
+
+
+.. function:: lookup(encoding)
+
+ Looks up the codec info in the Python codec registry and returns a
+ :class:`CodecInfo` object as defined above.
+
+ Encodings are first looked up in the registry's cache. If not found, the list of
+ registered search functions is scanned. If no :class:`CodecInfo` object is
+ found, a :exc:`LookupError` is raised. Otherwise, the :class:`CodecInfo` object
+ is stored in the cache and returned to the caller.
+
+To simplify access to the various codecs, the module provides these additional
+functions which use :func:`lookup` for the codec lookup:
+
+
+.. function:: getencoder(encoding)
+
+ Look up the codec for the given encoding and return its encoder function.
+
+ Raises a :exc:`LookupError` in case the encoding cannot be found.
+
+
+.. function:: getdecoder(encoding)
+
+ Look up the codec for the given encoding and return its decoder function.
+
+ Raises a :exc:`LookupError` in case the encoding cannot be found.
+
+
+.. function:: getincrementalencoder(encoding)
+
+ Look up the codec for the given encoding and return its incremental encoder
+ class or factory function.
+
+ Raises a :exc:`LookupError` in case the encoding cannot be found or the codec
+ doesn't support an incremental encoder.
+
+ .. versionadded:: 2.5
+
+
+.. function:: getincrementaldecoder(encoding)
+
+ Look up the codec for the given encoding and return its incremental decoder
+ class or factory function.
+
+ Raises a :exc:`LookupError` in case the encoding cannot be found or the codec
+ doesn't support an incremental decoder.
+
+ .. versionadded:: 2.5
+
+
+.. function:: getreader(encoding)
+
+ Look up the codec for the given encoding and return its StreamReader class or
+ factory function.
+
+ Raises a :exc:`LookupError` in case the encoding cannot be found.
+
+
+.. function:: getwriter(encoding)
+
+ Look up the codec for the given encoding and return its StreamWriter class or
+ factory function.
+
+ Raises a :exc:`LookupError` in case the encoding cannot be found.
+
+
+.. function:: register_error(name, error_handler)
+
+ Register the error handling function *error_handler* under the name *name*.
+ *error_handler* will be called during encoding and decoding in case of an error,
+ when *name* is specified as the errors parameter.
+
+ For encoding *error_handler* will be called with a :exc:`UnicodeEncodeError`
+ instance, which contains information about the location of the error. The error
+ handler must either raise this or a different exception or return a tuple with a
+ replacement for the unencodable part of the input and a position where encoding
+ should continue. The encoder will encode the replacement and continue encoding
+ the original input at the specified position. Negative position values will be
+ treated as being relative to the end of the input string. If the resulting
+ position is out of bound an :exc:`IndexError` will be raised.
+
+ Decoding and translating works similar, except :exc:`UnicodeDecodeError` or
+ :exc:`UnicodeTranslateError` will be passed to the handler and that the
+ replacement from the error handler will be put into the output directly.
+
+
+.. function:: lookup_error(name)
+
+ Return the error handler previously registered under the name *name*.
+
+ Raises a :exc:`LookupError` in case the handler cannot be found.
+
+
+.. function:: strict_errors(exception)
+
+ Implements the ``strict`` error handling.
+
+
+.. function:: replace_errors(exception)
+
+ Implements the ``replace`` error handling.
+
+
+.. function:: ignore_errors(exception)
+
+ Implements the ``ignore`` error handling.
+
+
+.. function:: xmlcharrefreplace_errors_errors(exception)
+
+ Implements the ``xmlcharrefreplace`` error handling.
+
+
+.. function:: backslashreplace_errors_errors(exception)
+
+ Implements the ``backslashreplace`` error handling.
+
+To simplify working with encoded files or stream, the module also defines these
+utility functions:
+
+
+.. function:: open(filename, mode[, encoding[, errors[, buffering]]])
+
+ Open an encoded file using the given *mode* and return a wrapped version
+ providing transparent encoding/decoding.
+
+ .. note::
+
+ The wrapped version will only accept the object format defined by the codecs,
+ i.e. Unicode objects for most built-in codecs. Output is also codec-dependent
+ and will usually be Unicode as well.
+
+ *encoding* specifies the encoding which is to be used for the file.
+
+ *errors* may be given to define the error handling. It defaults to ``'strict'``
+ which causes a :exc:`ValueError` to be raised in case an encoding error occurs.
+
+ *buffering* has the same meaning as for the built-in :func:`open` function. It
+ defaults to line buffered.
+
+
+.. function:: EncodedFile(file, input[, output[, errors]])
+
+ Return a wrapped version of file which provides transparent encoding
+ translation.
+
+ Strings written to the wrapped file are interpreted according to the given
+ *input* encoding and then written to the original file as strings using the
+ *output* encoding. The intermediate encoding will usually be Unicode but depends
+ on the specified codecs.
+
+ If *output* is not given, it defaults to *input*.
+
+ *errors* may be given to define the error handling. It defaults to ``'strict'``,
+ which causes :exc:`ValueError` to be raised in case an encoding error occurs.
+
+
+.. function:: iterencode(iterable, encoding[, errors])
+
+ Uses an incremental encoder to iteratively encode the input provided by
+ *iterable*. This function is a generator. *errors* (as well as any other keyword
+ argument) is passed through to the incremental encoder.
+
+ .. versionadded:: 2.5
+
+
+.. function:: iterdecode(iterable, encoding[, errors])
+
+ Uses an incremental decoder to iteratively decode the input provided by
+ *iterable*. This function is a generator. *errors* (as well as any other keyword
+ argument) is passed through to the incremental decoder.
+
+ .. versionadded:: 2.5
+
+The module also provides the following constants which are useful for reading
+and writing to platform dependent files:
+
+
+.. data:: BOM
+ BOM_BE
+ BOM_LE
+ BOM_UTF8
+ BOM_UTF16
+ BOM_UTF16_BE
+ BOM_UTF16_LE
+ BOM_UTF32
+ BOM_UTF32_BE
+ BOM_UTF32_LE
+
+ These constants define various encodings of the Unicode byte order mark (BOM)
+ used in UTF-16 and UTF-32 data streams to indicate the byte order used in the
+ stream or file and in UTF-8 as a Unicode signature. :const:`BOM_UTF16` is either
+ :const:`BOM_UTF16_BE` or :const:`BOM_UTF16_LE` depending on the platform's
+ native byte order, :const:`BOM` is an alias for :const:`BOM_UTF16`,
+ :const:`BOM_LE` for :const:`BOM_UTF16_LE` and :const:`BOM_BE` for
+ :const:`BOM_UTF16_BE`. The others represent the BOM in UTF-8 and UTF-32
+ encodings.
+
+
+.. _codec-base-classes:
+
+Codec Base Classes
+------------------
+
+The :mod:`codecs` module defines a set of base classes which define the
+interface and can also be used to easily write you own codecs for use in Python.
+
+Each codec has to define four interfaces to make it usable as codec in Python:
+stateless encoder, stateless decoder, stream reader and stream writer. The
+stream reader and writers typically reuse the stateless encoder/decoder to
+implement the file protocols.
+
+The :class:`Codec` class defines the interface for stateless encoders/decoders.
+
+To simplify and standardize error handling, the :meth:`encode` and
+:meth:`decode` methods may implement different error handling schemes by
+providing the *errors* string argument. The following string values are defined
+and implemented by all standard Python codecs:
+
++-------------------------+-----------------------------------------------+
+| Value | Meaning |
++=========================+===============================================+
+| ``'strict'`` | Raise :exc:`UnicodeError` (or a subclass); |
+| | this is the default. |
++-------------------------+-----------------------------------------------+
+| ``'ignore'`` | Ignore the character and continue with the |
+| | next. |
++-------------------------+-----------------------------------------------+
+| ``'replace'`` | Replace with a suitable replacement |
+| | character; Python will use the official |
+| | U+FFFD REPLACEMENT CHARACTER for the built-in |
+| | Unicode codecs on decoding and '?' on |
+| | encoding. |
++-------------------------+-----------------------------------------------+
+| ``'xmlcharrefreplace'`` | Replace with the appropriate XML character |
+| | reference (only for encoding). |
++-------------------------+-----------------------------------------------+
+| ``'backslashreplace'`` | Replace with backslashed escape sequences |
+| | (only for encoding). |
++-------------------------+-----------------------------------------------+
+
+The set of allowed values can be extended via :meth:`register_error`.
+
+
+.. _codec-objects:
+
+Codec Objects
+^^^^^^^^^^^^^
+
+The :class:`Codec` class defines these methods which also define the function
+interfaces of the stateless encoder and decoder:
+
+
+.. method:: Codec.encode(input[, errors])
+
+ Encodes the object *input* and returns a tuple (output object, length consumed).
+ While codecs are not restricted to use with Unicode, in a Unicode context,
+ encoding converts a Unicode object to a plain string using a particular
+ character set encoding (e.g., ``cp1252`` or ``iso-8859-1``).
+
+ *errors* defines the error handling to apply. It defaults to ``'strict'``
+ handling.
+
+ The method may not store state in the :class:`Codec` instance. Use
+ :class:`StreamCodec` for codecs which have to keep state in order to make
+ encoding/decoding efficient.
+
+ The encoder must be able to handle zero length input and return an empty object
+ of the output object type in this situation.
+
+
+.. method:: Codec.decode(input[, errors])
+
+ Decodes the object *input* and returns a tuple (output object, length consumed).
+ In a Unicode context, decoding converts a plain string encoded using a
+ particular character set encoding to a Unicode object.
+
+ *input* must be an object which provides the ``bf_getreadbuf`` buffer slot.
+ Python strings, buffer objects and memory mapped files are examples of objects
+ providing this slot.
+
+ *errors* defines the error handling to apply. It defaults to ``'strict'``
+ handling.
+
+ The method may not store state in the :class:`Codec` instance. Use
+ :class:`StreamCodec` for codecs which have to keep state in order to make
+ encoding/decoding efficient.
+
+ The decoder must be able to handle zero length input and return an empty object
+ of the output object type in this situation.
+
+The :class:`IncrementalEncoder` and :class:`IncrementalDecoder` classes provide
+the basic interface for incremental encoding and decoding. Encoding/decoding the
+input isn't done with one call to the stateless encoder/decoder function, but
+with multiple calls to the :meth:`encode`/:meth:`decode` method of the
+incremental encoder/decoder. The incremental encoder/decoder keeps track of the
+encoding/decoding process during method calls.
+
+The joined output of calls to the :meth:`encode`/:meth:`decode` method is the
+same as if all the single inputs were joined into one, and this input was
+encoded/decoded with the stateless encoder/decoder.
+
+
+.. _incremental-encoder-objects:
+
+IncrementalEncoder Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. versionadded:: 2.5
+
+The :class:`IncrementalEncoder` class is used for encoding an input in multiple
+steps. It defines the following methods which every incremental encoder must
+define in order to be compatible with the Python codec registry.
+
+
+.. class:: IncrementalEncoder([errors])
+
+ Constructor for an :class:`IncrementalEncoder` instance.
+
+ All incremental encoders must provide this constructor interface. They are free
+ to add additional keyword arguments, but only the ones defined here are used by
+ the Python codec registry.
+
+ The :class:`IncrementalEncoder` may implement different error handling schemes
+ by providing the *errors* keyword argument. These parameters are predefined:
+
+ * ``'strict'`` Raise :exc:`ValueError` (or a subclass); this is the default.
+
+ * ``'ignore'`` Ignore the character and continue with the next.
+
+ * ``'replace'`` Replace with a suitable replacement character
+
+ * ``'xmlcharrefreplace'`` Replace with the appropriate XML character reference
+
+ * ``'backslashreplace'`` Replace with backslashed escape sequences.
+
+ The *errors* argument will be assigned to an attribute of the same name.
+ Assigning to this attribute makes it possible to switch between different error
+ handling strategies during the lifetime of the :class:`IncrementalEncoder`
+ object.
+
+ The set of allowed values for the *errors* argument can be extended with
+ :func:`register_error`.
+
+
+.. method:: IncrementalEncoder.encode(object[, final])
+
+ Encodes *object* (taking the current state of the encoder into account) and
+ returns the resulting encoded object. If this is the last call to :meth:`encode`
+ *final* must be true (the default is false).
+
+
+.. method:: IncrementalEncoder.reset()
+
+ Reset the encoder to the initial state.
+
+
+.. method:: IncrementalEncoder.getstate()
+
+ Return the current state of the encoder which must be an integer. The
+ implementation should make sure that ``0`` is the most common state. (States
+ that are more complicated than integers can be converted into an integer by
+ marshaling/pickling the state and encoding the bytes of the resulting string
+ into an integer).
+
+ .. versionadded:: 3.0
+
+
+.. method:: IncrementalEncoder.setstate(state)
+
+ Set the state of the encoder to *state*. *state* must be an encoder state
+ returned by :meth:`getstate`.
+
+ .. versionadded:: 3.0
+
+
+.. _incremental-decoder-objects:
+
+IncrementalDecoder Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The :class:`IncrementalDecoder` class is used for decoding an input in multiple
+steps. It defines the following methods which every incremental decoder must
+define in order to be compatible with the Python codec registry.
+
+
+.. class:: IncrementalDecoder([errors])
+
+ Constructor for an :class:`IncrementalDecoder` instance.
+
+ All incremental decoders must provide this constructor interface. They are free
+ to add additional keyword arguments, but only the ones defined here are used by
+ the Python codec registry.
+
+ The :class:`IncrementalDecoder` may implement different error handling schemes
+ by providing the *errors* keyword argument. These parameters are predefined:
+
+ * ``'strict'`` Raise :exc:`ValueError` (or a subclass); this is the default.
+
+ * ``'ignore'`` Ignore the character and continue with the next.
+
+ * ``'replace'`` Replace with a suitable replacement character.
+
+ The *errors* argument will be assigned to an attribute of the same name.
+ Assigning to this attribute makes it possible to switch between different error
+ handling strategies during the lifetime of the :class:`IncrementalEncoder`
+ object.
+
+ The set of allowed values for the *errors* argument can be extended with
+ :func:`register_error`.
+
+
+.. method:: IncrementalDecoder.decode(object[, final])
+
+ Decodes *object* (taking the current state of the decoder into account) and
+ returns the resulting decoded object. If this is the last call to :meth:`decode`
+ *final* must be true (the default is false). If *final* is true the decoder must
+ decode the input completely and must flush all buffers. If this isn't possible
+ (e.g. because of incomplete byte sequences at the end of the input) it must
+ initiate error handling just like in the stateless case (which might raise an
+ exception).
+
+
+.. method:: IncrementalDecoder.reset()
+
+ Reset the decoder to the initial state.
+
+
+.. method:: IncrementalDecoder.getstate()
+
+ Return the current state of the decoder. This must be a tuple with two items,
+ the first must be the buffer containing the still undecoded input. The second
+ must be an integer and can be additional state info. (The implementation should
+ make sure that ``0`` is the most common additional state info.) If this
+ additional state info is ``0`` it must be possible to set the decoder to the
+ state which has no input buffered and ``0`` as the additional state info, so
+ that feeding the previously buffered input to the decoder returns it to the
+ previous state without producing any output. (Additional state info that is more
+ complicated than integers can be converted into an integer by
+ marshaling/pickling the info and encoding the bytes of the resulting string into
+ an integer.)
+
+ .. versionadded:: 3.0
+
+
+.. method:: IncrementalDecoder.setstate(state)
+
+ Set the state of the encoder to *state*. *state* must be a decoder state
+ returned by :meth:`getstate`.
+
+ .. versionadded:: 3.0
+
+The :class:`StreamWriter` and :class:`StreamReader` classes provide generic
+working interfaces which can be used to implement new encoding submodules very
+easily. See :mod:`encodings.utf_8` for an example of how this is done.
+
+
+.. _stream-writer-objects:
+
+StreamWriter Objects
+^^^^^^^^^^^^^^^^^^^^
+
+The :class:`StreamWriter` class is a subclass of :class:`Codec` and defines the
+following methods which every stream writer must define in order to be
+compatible with the Python codec registry.
+
+
+.. class:: StreamWriter(stream[, errors])
+
+ Constructor for a :class:`StreamWriter` instance.
+
+ All stream writers must provide this constructor interface. They are free to add
+ additional keyword arguments, but only the ones defined here are used by the
+ Python codec registry.
+
+ *stream* must be a file-like object open for writing binary data.
+
+ The :class:`StreamWriter` may implement different error handling schemes by
+ providing the *errors* keyword argument. These parameters are predefined:
+
+ * ``'strict'`` Raise :exc:`ValueError` (or a subclass); this is the default.
+
+ * ``'ignore'`` Ignore the character and continue with the next.
+
+ * ``'replace'`` Replace with a suitable replacement character
+
+ * ``'xmlcharrefreplace'`` Replace with the appropriate XML character reference
+
+ * ``'backslashreplace'`` Replace with backslashed escape sequences.
+
+ The *errors* argument will be assigned to an attribute of the same name.
+ Assigning to this attribute makes it possible to switch between different error
+ handling strategies during the lifetime of the :class:`StreamWriter` object.
+
+ The set of allowed values for the *errors* argument can be extended with
+ :func:`register_error`.
+
+
+.. method:: StreamWriter.write(object)
+
+ Writes the object's contents encoded to the stream.
+
+
+.. method:: StreamWriter.writelines(list)
+
+ Writes the concatenated list of strings to the stream (possibly by reusing the
+ :meth:`write` method).
+
+
+.. method:: StreamWriter.reset()
+
+ Flushes and resets the codec buffers used for keeping state.
+
+ Calling this method should ensure that the data on the output is put into a
+ clean state that allows appending of new fresh data without having to rescan the
+ whole stream to recover state.
+
+In addition to the above methods, the :class:`StreamWriter` must also inherit
+all other methods and attributes from the underlying stream.
+
+
+.. _stream-reader-objects:
+
+StreamReader Objects
+^^^^^^^^^^^^^^^^^^^^
+
+The :class:`StreamReader` class is a subclass of :class:`Codec` and defines the
+following methods which every stream reader must define in order to be
+compatible with the Python codec registry.
+
+
+.. class:: StreamReader(stream[, errors])
+
+ Constructor for a :class:`StreamReader` instance.
+
+ All stream readers must provide this constructor interface. They are free to add
+ additional keyword arguments, but only the ones defined here are used by the
+ Python codec registry.
+
+ *stream* must be a file-like object open for reading (binary) data.
+
+ The :class:`StreamReader` may implement different error handling schemes by
+ providing the *errors* keyword argument. These parameters are defined:
+
+ * ``'strict'`` Raise :exc:`ValueError` (or a subclass); this is the default.
+
+ * ``'ignore'`` Ignore the character and continue with the next.
+
+ * ``'replace'`` Replace with a suitable replacement character.
+
+ The *errors* argument will be assigned to an attribute of the same name.
+ Assigning to this attribute makes it possible to switch between different error
+ handling strategies during the lifetime of the :class:`StreamReader` object.
+
+ The set of allowed values for the *errors* argument can be extended with
+ :func:`register_error`.
+
+
+.. method:: StreamReader.read([size[, chars, [firstline]]])
+
+ Decodes data from the stream and returns the resulting object.
+
+ *chars* indicates the number of characters to read from the stream. :func:`read`
+ will never return more than *chars* characters, but it might return less, if
+ there are not enough characters available.
+
+ *size* indicates the approximate maximum number of bytes to read from the stream
+ for decoding purposes. The decoder can modify this setting as appropriate. The
+ default value -1 indicates to read and decode as much as possible. *size* is
+ intended to prevent having to decode huge files in one step.
+
+ *firstline* indicates that it would be sufficient to only return the first line,
+ if there are decoding errors on later lines.
+
+ The method should use a greedy read strategy meaning that it should read as much
+ data as is allowed within the definition of the encoding and the given size,
+ e.g. if optional encoding endings or state markers are available on the stream,
+ these should be read too.
+
+ .. versionchanged:: 2.4
+ *chars* argument added.
+
+ .. versionchanged:: 2.4.2
+ *firstline* argument added.
+
+
+.. method:: StreamReader.readline([size[, keepends]])
+
+ Read one line from the input stream and return the decoded data.
+
+ *size*, if given, is passed as size argument to the stream's :meth:`readline`
+ method.
+
+ If *keepends* is false line-endings will be stripped from the lines returned.
+
+ .. versionchanged:: 2.4
+ *keepends* argument added.
+
+
+.. method:: StreamReader.readlines([sizehint[, keepends]])
+
+ Read all lines available on the input stream and return them as a list of lines.
+
+ Line-endings are implemented using the codec's decoder method and are included
+ in the list entries if *keepends* is true.
+
+ *sizehint*, if given, is passed as the *size* argument to the stream's
+ :meth:`read` method.
+
+
+.. method:: StreamReader.reset()
+
+ Resets the codec buffers used for keeping state.
+
+ Note that no stream repositioning should take place. This method is primarily
+ intended to be able to recover from decoding errors.
+
+In addition to the above methods, the :class:`StreamReader` must also inherit
+all other methods and attributes from the underlying stream.
+
+The next two base classes are included for convenience. They are not needed by
+the codec registry, but may provide useful in practice.
+
+
+.. _stream-reader-writer:
+
+StreamReaderWriter Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The :class:`StreamReaderWriter` allows wrapping streams which work in both read
+and write modes.
+
+The design is such that one can use the factory functions returned by the
+:func:`lookup` function to construct the instance.
+
+
+.. class:: StreamReaderWriter(stream, Reader, Writer, errors)
+
+ Creates a :class:`StreamReaderWriter` instance. *stream* must be a file-like
+ object. *Reader* and *Writer* must be factory functions or classes providing the
+ :class:`StreamReader` and :class:`StreamWriter` interface resp. Error handling
+ is done in the same way as defined for the stream readers and writers.
+
+:class:`StreamReaderWriter` instances define the combined interfaces of
+:class:`StreamReader` and :class:`StreamWriter` classes. They inherit all other
+methods and attributes from the underlying stream.
+
+
+.. _stream-recoder-objects:
+
+StreamRecoder Objects
+^^^^^^^^^^^^^^^^^^^^^
+
+The :class:`StreamRecoder` provide a frontend - backend view of encoding data
+which is sometimes useful when dealing with different encoding environments.
+
+The design is such that one can use the factory functions returned by the
+:func:`lookup` function to construct the instance.
+
+
+.. class:: StreamRecoder(stream, encode, decode, Reader, Writer, errors)
+
+ Creates a :class:`StreamRecoder` instance which implements a two-way conversion:
+ *encode* and *decode* work on the frontend (the input to :meth:`read` and output
+ of :meth:`write`) while *Reader* and *Writer* work on the backend (reading and
+ writing to the stream).
+
+ You can use these objects to do transparent direct recodings from e.g. Latin-1
+ to UTF-8 and back.
+
+ *stream* must be a file-like object.
+
+ *encode*, *decode* must adhere to the :class:`Codec` interface. *Reader*,
+ *Writer* must be factory functions or classes providing objects of the
+ :class:`StreamReader` and :class:`StreamWriter` interface respectively.
+
+ *encode* and *decode* are needed for the frontend translation, *Reader* and
+ *Writer* for the backend translation. The intermediate format used is
+ determined by the two sets of codecs, e.g. the Unicode codecs will use Unicode
+ as the intermediate encoding.
+
+ Error handling is done in the same way as defined for the stream readers and
+ writers.
+
+:class:`StreamRecoder` instances define the combined interfaces of
+:class:`StreamReader` and :class:`StreamWriter` classes. They inherit all other
+methods and attributes from the underlying stream.
+
+
+.. _encodings-overview:
+
+Encodings and Unicode
+---------------------
+
+Unicode strings are stored internally as sequences of codepoints (to be precise
+as :ctype:`Py_UNICODE` arrays). Depending on the way Python is compiled (either
+via :option:`--enable-unicode=ucs2` or :option:`--enable-unicode=ucs4`, with the
+former being the default) :ctype:`Py_UNICODE` is either a 16-bit or 32-bit data
+type. Once a Unicode object is used outside of CPU and memory, CPU endianness
+and how these arrays are stored as bytes become an issue. Transforming a
+unicode object into a sequence of bytes is called encoding and recreating the
+unicode object from the sequence of bytes is known as decoding. There are many
+different methods for how this transformation can be done (these methods are
+also called encodings). The simplest method is to map the codepoints 0-255 to
+the bytes ``0x0``-``0xff``. This means that a unicode object that contains
+codepoints above ``U+00FF`` can't be encoded with this method (which is called
+``'latin-1'`` or ``'iso-8859-1'``). :func:`unicode.encode` will raise a
+:exc:`UnicodeEncodeError` that looks like this: ``UnicodeEncodeError: 'latin-1'
+codec can't encode character u'\u1234' in position 3: ordinal not in
+range(256)``.
+
+There's another group of encodings (the so called charmap encodings) that choose
+a different subset of all unicode code points and how these codepoints are
+mapped to the bytes ``0x0``-``0xff``. To see how this is done simply open
+e.g. :file:`encodings/cp1252.py` (which is an encoding that is used primarily on
+Windows). There's a string constant with 256 characters that shows you which
+character is mapped to which byte value.
+
+All of these encodings can only encode 256 of the 65536 (or 1114111) codepoints
+defined in unicode. A simple and straightforward way that can store each Unicode
+code point, is to store each codepoint as two consecutive bytes. There are two
+possibilities: Store the bytes in big endian or in little endian order. These
+two encodings are called UTF-16-BE and UTF-16-LE respectively. Their
+disadvantage is that if e.g. you use UTF-16-BE on a little endian machine you
+will always have to swap bytes on encoding and decoding. UTF-16 avoids this
+problem: Bytes will always be in natural endianness. When these bytes are read
+by a CPU with a different endianness, then bytes have to be swapped though. To
+be able to detect the endianness of a UTF-16 byte sequence, there's the so
+called BOM (the "Byte Order Mark"). This is the Unicode character ``U+FEFF``.
+This character will be prepended to every UTF-16 byte sequence. The byte swapped
+version of this character (``0xFFFE``) is an illegal character that may not
+appear in a Unicode text. So when the first character in an UTF-16 byte sequence
+appears to be a ``U+FFFE`` the bytes have to be swapped on decoding.
+Unfortunately upto Unicode 4.0 the character ``U+FEFF`` had a second purpose as
+a ``ZERO WIDTH NO-BREAK SPACE``: A character that has no width and doesn't allow
+a word to be split. It can e.g. be used to give hints to a ligature algorithm.
+With Unicode 4.0 using ``U+FEFF`` as a ``ZERO WIDTH NO-BREAK SPACE`` has been
+deprecated (with ``U+2060`` (``WORD JOINER``) assuming this role). Nevertheless
+Unicode software still must be able to handle ``U+FEFF`` in both roles: As a BOM
+it's a device to determine the storage layout of the encoded bytes, and vanishes
+once the byte sequence has been decoded into a Unicode string; as a ``ZERO WIDTH
+NO-BREAK SPACE`` it's a normal character that will be decoded like any other.
+
+There's another encoding that is able to encoding the full range of Unicode
+characters: UTF-8. UTF-8 is an 8-bit encoding, which means there are no issues
+with byte order in UTF-8. Each byte in a UTF-8 byte sequence consists of two
+parts: Marker bits (the most significant bits) and payload bits. The marker bits
+are a sequence of zero to six 1 bits followed by a 0 bit. Unicode characters are
+encoded like this (with x being payload bits, which when concatenated give the
+Unicode character):
+
++-----------------------------------+----------------------------------------------+
+| Range | Encoding |
++===================================+==============================================+
+| ``U-00000000`` ... ``U-0000007F`` | 0xxxxxxx |
++-----------------------------------+----------------------------------------------+
+| ``U-00000080`` ... ``U-000007FF`` | 110xxxxx 10xxxxxx |
++-----------------------------------+----------------------------------------------+
+| ``U-00000800`` ... ``U-0000FFFF`` | 1110xxxx 10xxxxxx 10xxxxxx |
++-----------------------------------+----------------------------------------------+
+| ``U-00010000`` ... ``U-001FFFFF`` | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx |
++-----------------------------------+----------------------------------------------+
+| ``U-00200000`` ... ``U-03FFFFFF`` | 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx |
++-----------------------------------+----------------------------------------------+
+| ``U-04000000`` ... ``U-7FFFFFFF`` | 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx |
+| | 10xxxxxx |
++-----------------------------------+----------------------------------------------+
+
+The least significant bit of the Unicode character is the rightmost x bit.
+
+As UTF-8 is an 8-bit encoding no BOM is required and any ``U+FEFF`` character in
+the decoded Unicode string (even if it's the first character) is treated as a
+``ZERO WIDTH NO-BREAK SPACE``.
+
+Without external information it's impossible to reliably determine which
+encoding was used for encoding a Unicode string. Each charmap encoding can
+decode any random byte sequence. However that's not possible with UTF-8, as
+UTF-8 byte sequences have a structure that doesn't allow arbitrary byte
+sequence. To increase the reliability with which a UTF-8 encoding can be
+detected, Microsoft invented a variant of UTF-8 (that Python 2.5 calls
+``"utf-8-sig"``) for its Notepad program: Before any of the Unicode characters
+is written to the file, a UTF-8 encoded BOM (which looks like this as a byte
+sequence: ``0xef``, ``0xbb``, ``0xbf``) is written. As it's rather improbable
+that any charmap encoded file starts with these byte values (which would e.g.
+map to
+
+ | LATIN SMALL LETTER I WITH DIAERESIS
+ | RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK
+ | INVERTED QUESTION MARK
+
+in iso-8859-1), this increases the probability that a utf-8-sig encoding can be
+correctly guessed from the byte sequence. So here the BOM is not used to be able
+to determine the byte order used for generating the byte sequence, but as a
+signature that helps in guessing the encoding. On encoding the utf-8-sig codec
+will write ``0xef``, ``0xbb``, ``0xbf`` as the first three bytes to the file. On
+decoding utf-8-sig will skip those three bytes if they appear as the first three
+bytes in the file.
+
+
+.. _standard-encodings:
+
+Standard Encodings
+------------------
+
+Python comes with a number of codecs built-in, either implemented as C functions
+or with dictionaries as mapping tables. The following table lists the codecs by
+name, together with a few common aliases, and the languages for which the
+encoding is likely used. Neither the list of aliases nor the list of languages
+is meant to be exhaustive. Notice that spelling alternatives that only differ in
+case or use a hyphen instead of an underscore are also valid aliases.
+
+Many of the character sets support the same languages. They vary in individual
+characters (e.g. whether the EURO SIGN is supported or not), and in the
+assignment of characters to code positions. For the European languages in
+particular, the following variants typically exist:
+
+* an ISO 8859 codeset
+
+* a Microsoft Windows code page, which is typically derived from a 8859 codeset,
+ but replaces control characters with additional graphic characters
+
+* an IBM EBCDIC code page
+
+* an IBM PC code page, which is ASCII compatible
+
++-----------------+--------------------------------+--------------------------------+
+| Codec | Aliases | Languages |
++=================+================================+================================+
+| ascii | 646, us-ascii | English |
++-----------------+--------------------------------+--------------------------------+
+| big5 | big5-tw, csbig5 | Traditional Chinese |
++-----------------+--------------------------------+--------------------------------+
+| big5hkscs | big5-hkscs, hkscs | Traditional Chinese |
++-----------------+--------------------------------+--------------------------------+
+| cp037 | IBM037, IBM039 | English |
++-----------------+--------------------------------+--------------------------------+
+| cp424 | EBCDIC-CP-HE, IBM424 | Hebrew |
++-----------------+--------------------------------+--------------------------------+
+| cp437 | 437, IBM437 | English |
++-----------------+--------------------------------+--------------------------------+
+| cp500 | EBCDIC-CP-BE, EBCDIC-CP-CH, | Western Europe |
+| | IBM500 | |
++-----------------+--------------------------------+--------------------------------+
+| cp737 | | Greek |
++-----------------+--------------------------------+--------------------------------+
+| cp775 | IBM775 | Baltic languages |
++-----------------+--------------------------------+--------------------------------+
+| cp850 | 850, IBM850 | Western Europe |
++-----------------+--------------------------------+--------------------------------+
+| cp852 | 852, IBM852 | Central and Eastern Europe |
++-----------------+--------------------------------+--------------------------------+
+| cp855 | 855, IBM855 | Bulgarian, Byelorussian, |
+| | | Macedonian, Russian, Serbian |
++-----------------+--------------------------------+--------------------------------+
+| cp856 | | Hebrew |
++-----------------+--------------------------------+--------------------------------+
+| cp857 | 857, IBM857 | Turkish |
++-----------------+--------------------------------+--------------------------------+
+| cp860 | 860, IBM860 | Portuguese |
++-----------------+--------------------------------+--------------------------------+
+| cp861 | 861, CP-IS, IBM861 | Icelandic |
++-----------------+--------------------------------+--------------------------------+
+| cp862 | 862, IBM862 | Hebrew |
++-----------------+--------------------------------+--------------------------------+
+| cp863 | 863, IBM863 | Canadian |
++-----------------+--------------------------------+--------------------------------+
+| cp864 | IBM864 | Arabic |
++-----------------+--------------------------------+--------------------------------+
+| cp865 | 865, IBM865 | Danish, Norwegian |
++-----------------+--------------------------------+--------------------------------+
+| cp866 | 866, IBM866 | Russian |
++-----------------+--------------------------------+--------------------------------+
+| cp869 | 869, CP-GR, IBM869 | Greek |
++-----------------+--------------------------------+--------------------------------+
+| cp874 | | Thai |
++-----------------+--------------------------------+--------------------------------+
+| cp875 | | Greek |
++-----------------+--------------------------------+--------------------------------+
+| cp932 | 932, ms932, mskanji, ms-kanji | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| cp949 | 949, ms949, uhc | Korean |
++-----------------+--------------------------------+--------------------------------+
+| cp950 | 950, ms950 | Traditional Chinese |
++-----------------+--------------------------------+--------------------------------+
+| cp1006 | | Urdu |
++-----------------+--------------------------------+--------------------------------+
+| cp1026 | ibm1026 | Turkish |
++-----------------+--------------------------------+--------------------------------+
+| cp1140 | ibm1140 | Western Europe |
++-----------------+--------------------------------+--------------------------------+
+| cp1250 | windows-1250 | Central and Eastern Europe |
++-----------------+--------------------------------+--------------------------------+
+| cp1251 | windows-1251 | Bulgarian, Byelorussian, |
+| | | Macedonian, Russian, Serbian |
++-----------------+--------------------------------+--------------------------------+
+| cp1252 | windows-1252 | Western Europe |
++-----------------+--------------------------------+--------------------------------+
+| cp1253 | windows-1253 | Greek |
++-----------------+--------------------------------+--------------------------------+
+| cp1254 | windows-1254 | Turkish |
++-----------------+--------------------------------+--------------------------------+
+| cp1255 | windows-1255 | Hebrew |
++-----------------+--------------------------------+--------------------------------+
+| cp1256 | windows1256 | Arabic |
++-----------------+--------------------------------+--------------------------------+
+| cp1257 | windows-1257 | Baltic languages |
++-----------------+--------------------------------+--------------------------------+
+| cp1258 | windows-1258 | Vietnamese |
++-----------------+--------------------------------+--------------------------------+
+| euc_jp | eucjp, ujis, u-jis | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| euc_jis_2004 | jisx0213, eucjis2004 | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| euc_jisx0213 | eucjisx0213 | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| euc_kr | euckr, korean, ksc5601, | Korean |
+| | ks_c-5601, ks_c-5601-1987, | |
+| | ksx1001, ks_x-1001 | |
++-----------------+--------------------------------+--------------------------------+
+| gb2312 | chinese, csiso58gb231280, euc- | Simplified Chinese |
+| | cn, euccn, eucgb2312-cn, | |
+| | gb2312-1980, gb2312-80, iso- | |
+| | ir-58 | |
++-----------------+--------------------------------+--------------------------------+
+| gbk | 936, cp936, ms936 | Unified Chinese |
++-----------------+--------------------------------+--------------------------------+
+| gb18030 | gb18030-2000 | Unified Chinese |
++-----------------+--------------------------------+--------------------------------+
+| hz | hzgb, hz-gb, hz-gb-2312 | Simplified Chinese |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_jp | csiso2022jp, iso2022jp, | Japanese |
+| | iso-2022-jp | |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_jp_1 | iso2022jp-1, iso-2022-jp-1 | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_jp_2 | iso2022jp-2, iso-2022-jp-2 | Japanese, Korean, Simplified |
+| | | Chinese, Western Europe, Greek |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_jp_2004 | iso2022jp-2004, | Japanese |
+| | iso-2022-jp-2004 | |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_jp_3 | iso2022jp-3, iso-2022-jp-3 | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_jp_ext | iso2022jp-ext, iso-2022-jp-ext | Japanese |
++-----------------+--------------------------------+--------------------------------+
+| iso2022_kr | csiso2022kr, iso2022kr, | Korean |
+| | iso-2022-kr | |
++-----------------+--------------------------------+--------------------------------+
+| latin_1 | iso-8859-1, iso8859-1, 8859, | West Europe |
+| | cp819, latin, latin1, L1 | |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_2 | iso-8859-2, latin2, L2 | Central and Eastern Europe |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_3 | iso-8859-3, latin3, L3 | Esperanto, Maltese |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_4 | iso-8859-4, latin4, L4 | Baltic languagues |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_5 | iso-8859-5, cyrillic | Bulgarian, Byelorussian, |
+| | | Macedonian, Russian, Serbian |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_6 | iso-8859-6, arabic | Arabic |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_7 | iso-8859-7, greek, greek8 | Greek |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_8 | iso-8859-8, hebrew | Hebrew |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_9 | iso-8859-9, latin5, L5 | Turkish |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_10 | iso-8859-10, latin6, L6 | Nordic languages |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_13 | iso-8859-13 | Baltic languages |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_14 | iso-8859-14, latin8, L8 | Celtic languages |
++-----------------+--------------------------------+--------------------------------+
+| iso8859_15 | iso-8859-15 | Western Europe |
++-----------------+--------------------------------+--------------------------------+
+| johab | cp1361, ms1361 | Korean |
++-----------------+--------------------------------+--------------------------------+
+| koi8_r | | Russian |
++-----------------+--------------------------------+--------------------------------+
+| koi8_u | | Ukrainian |
++-----------------+--------------------------------+--------------------------------+
+| mac_cyrillic | maccyrillic | Bulgarian, Byelorussian, |
+| | | Macedonian, Russian, Serbian |
++-----------------+--------------------------------+--------------------------------+
+| mac_greek | macgreek | Greek |
++-----------------+--------------------------------+--------------------------------+
+| mac_iceland | maciceland | Icelandic |
++-----------------+--------------------------------+--------------------------------+
+| mac_latin2 | maclatin2, maccentraleurope | Central and Eastern Europe |
++-----------------+--------------------------------+--------------------------------+
+| mac_roman | macroman | Western Europe |
++-----------------+--------------------------------+--------------------------------+
+| mac_turkish | macturkish | Turkish |
++-----------------+--------------------------------+--------------------------------+
+| ptcp154 | csptcp154, pt154, cp154, | Kazakh |
+| | cyrillic-asian | |
++-----------------+--------------------------------+--------------------------------+
+| shift_jis | csshiftjis, shiftjis, sjis, | Japanese |
+| | s_jis | |
++-----------------+--------------------------------+--------------------------------+
+| shift_jis_2004 | shiftjis2004, sjis_2004, | Japanese |
+| | sjis2004 | |
++-----------------+--------------------------------+--------------------------------+
+| shift_jisx0213 | shiftjisx0213, sjisx0213, | Japanese |
+| | s_jisx0213 | |
++-----------------+--------------------------------+--------------------------------+
+| utf_16 | U16, utf16 | all languages |
++-----------------+--------------------------------+--------------------------------+
+| utf_16_be | UTF-16BE | all languages (BMP only) |
++-----------------+--------------------------------+--------------------------------+
+| utf_16_le | UTF-16LE | all languages (BMP only) |
++-----------------+--------------------------------+--------------------------------+
+| utf_7 | U7, unicode-1-1-utf-7 | all languages |
++-----------------+--------------------------------+--------------------------------+
+| utf_8 | U8, UTF, utf8 | all languages |
++-----------------+--------------------------------+--------------------------------+
+| utf_8_sig | | all languages |
++-----------------+--------------------------------+--------------------------------+
+
+A number of codecs are specific to Python, so their codec names have no meaning
+outside Python. Some of them don't convert from Unicode strings to byte strings,
+but instead use the property of the Python codecs machinery that any bijective
+function with one argument can be considered as an encoding.
+
+For the codecs listed below, the result in the "encoding" direction is always a
+byte string. The result of the "decoding" direction is listed as operand type in
+the table.
+
++--------------------+---------+----------------+---------------------------+
+| Codec | Aliases | Operand type | Purpose |
++====================+=========+================+===========================+
+| idna | | Unicode string | Implements :rfc:`3490`, |
+| | | | see also |
+| | | | :mod:`encodings.idna` |
++--------------------+---------+----------------+---------------------------+
+| mbcs | dbcs | Unicode string | Windows only: Encode |
+| | | | operand according to the |
+| | | | ANSI codepage (CP_ACP) |
++--------------------+---------+----------------+---------------------------+
+| palmos | | Unicode string | Encoding of PalmOS 3.5 |
++--------------------+---------+----------------+---------------------------+
+| punycode | | Unicode string | Implements :rfc:`3492` |
++--------------------+---------+----------------+---------------------------+
+| raw_unicode_escape | | Unicode string | Produce a string that is |
+| | | | suitable as raw Unicode |
+| | | | literal in Python source |
+| | | | code |
++--------------------+---------+----------------+---------------------------+
+| undefined | | any | Raise an exception for |
+| | | | all conversions. Can be |
+| | | | used as the system |
+| | | | encoding if no automatic |
+| | | | coercion between byte and |
+| | | | Unicode strings is |
+| | | | desired. |
++--------------------+---------+----------------+---------------------------+
+| unicode_escape | | Unicode string | Produce a string that is |
+| | | | suitable as Unicode |
+| | | | literal in Python source |
+| | | | code |
++--------------------+---------+----------------+---------------------------+
+| unicode_internal | | Unicode string | Return the internal |
+| | | | representation of the |
+| | | | operand |
++--------------------+---------+----------------+---------------------------+
+
+.. versionadded:: 2.3
+ The ``idna`` and ``punycode`` encodings.
+
+
+:mod:`encodings.idna` --- Internationalized Domain Names in Applications
+------------------------------------------------------------------------
+
+.. module:: encodings.idna
+ :synopsis: Internationalized Domain Names implementation
+.. moduleauthor:: Martin v. Löwis
+
+.. versionadded:: 2.3
+
+This module implements :rfc:`3490` (Internationalized Domain Names in
+Applications) and :rfc:`3492` (Nameprep: A Stringprep Profile for
+Internationalized Domain Names (IDN)). It builds upon the ``punycode`` encoding
+and :mod:`stringprep`.
+
+These RFCs together define a protocol to support non-ASCII characters in domain
+names. A domain name containing non-ASCII characters (such as
+``www.Alliancefrançaise.nu``) is converted into an ASCII-compatible encoding
+(ACE, such as ``www.xn--alliancefranaise-npb.nu``). The ACE form of the domain
+name is then used in all places where arbitrary characters are not allowed by
+the protocol, such as DNS queries, HTTP :mailheader:`Host` fields, and so
+on. This conversion is carried out in the application; if possible invisible to
+the user: The application should transparently convert Unicode domain labels to
+IDNA on the wire, and convert back ACE labels to Unicode before presenting them
+to the user.
+
+Python supports this conversion in several ways: The ``idna`` codec allows to
+convert between Unicode and the ACE. Furthermore, the :mod:`socket` module
+transparently converts Unicode host names to ACE, so that applications need not
+be concerned about converting host names themselves when they pass them to the
+socket module. On top of that, modules that have host names as function
+parameters, such as :mod:`httplib` and :mod:`ftplib`, accept Unicode host names
+(:mod:`httplib` then also transparently sends an IDNA hostname in the
+:mailheader:`Host` field if it sends that field at all).
+
+When receiving host names from the wire (such as in reverse name lookup), no
+automatic conversion to Unicode is performed: Applications wishing to present
+such host names to the user should decode them to Unicode.
+
+The module :mod:`encodings.idna` also implements the nameprep procedure, which
+performs certain normalizations on host names, to achieve case-insensitivity of
+international domain names, and to unify similar characters. The nameprep
+functions can be used directly if desired.
+
+
+.. function:: nameprep(label)
+
+ Return the nameprepped version of *label*. The implementation currently assumes
+ query strings, so ``AllowUnassigned`` is true.
+
+
+.. function:: ToASCII(label)
+
+ Convert a label to ASCII, as specified in :rfc:`3490`. ``UseSTD3ASCIIRules`` is
+ assumed to be false.
+
+
+.. function:: ToUnicode(label)
+
+ Convert a label to Unicode, as specified in :rfc:`3490`.
+
+
+:mod:`encodings.utf_8_sig` --- UTF-8 codec with BOM signature
+-------------------------------------------------------------
+
+.. module:: encodings.utf_8_sig
+ :synopsis: UTF-8 codec with BOM signature
+.. moduleauthor:: Walter Dörwald
+
+.. versionadded:: 2.5
+
+This module implements a variant of the UTF-8 codec: On encoding a UTF-8 encoded
+BOM will be prepended to the UTF-8 encoded bytes. For the stateful encoder this
+is only done once (on the first write to the byte stream). For decoding an
+optional UTF-8 encoded BOM at the start of the data will be skipped.
+
diff --git a/Doc/library/codeop.rst b/Doc/library/codeop.rst
new file mode 100644
index 0000000000..8a730ec027
--- /dev/null
+++ b/Doc/library/codeop.rst
@@ -0,0 +1,95 @@
+
+:mod:`codeop` --- Compile Python code
+=====================================
+
+.. module:: codeop
+ :synopsis: Compile (possibly incomplete) Python code.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+.. sectionauthor:: Michael Hudson <mwh@python.net>
+
+
+.. % LaTeXed from excellent doc-string.
+
+The :mod:`codeop` module provides utilities upon which the Python
+read-eval-print loop can be emulated, as is done in the :mod:`code` module. As
+a result, you probably don't want to use the module directly; if you want to
+include such a loop in your program you probably want to use the :mod:`code`
+module instead.
+
+There are two parts to this job:
+
+#. Being able to tell if a line of input completes a Python statement: in
+ short, telling whether to print '``>>>``' or '``...``' next.
+
+#. Remembering which future statements the user has entered, so subsequent
+ input can be compiled with these in effect.
+
+The :mod:`codeop` module provides a way of doing each of these things, and a way
+of doing them both.
+
+To do just the former:
+
+
+.. function:: compile_command(source[, filename[, symbol]])
+
+ Tries to compile *source*, which should be a string of Python code and return a
+ code object if *source* is valid Python code. In that case, the filename
+ attribute of the code object will be *filename*, which defaults to
+ ``'<input>'``. Returns ``None`` if *source* is *not* valid Python code, but is a
+ prefix of valid Python code.
+
+ If there is a problem with *source*, an exception will be raised.
+ :exc:`SyntaxError` is raised if there is invalid Python syntax, and
+ :exc:`OverflowError` or :exc:`ValueError` if there is an invalid literal.
+
+ The *symbol* argument determines whether *source* is compiled as a statement
+ (``'single'``, the default) or as an expression (``'eval'``). Any other value
+ will cause :exc:`ValueError` to be raised.
+
+ **Caveat:** It is possible (but not likely) that the parser stops parsing with a
+ successful outcome before reaching the end of the source; in this case, trailing
+ symbols may be ignored instead of causing an error. For example, a backslash
+ followed by two newlines may be followed by arbitrary garbage. This will be
+ fixed once the API for the parser is better.
+
+
+.. class:: Compile()
+
+ Instances of this class have :meth:`__call__` methods identical in signature to
+ the built-in function :func:`compile`, but with the difference that if the
+ instance compiles program text containing a :mod:`__future__` statement, the
+ instance 'remembers' and compiles all subsequent program texts with the
+ statement in force.
+
+
+.. class:: CommandCompiler()
+
+ Instances of this class have :meth:`__call__` methods identical in signature to
+ :func:`compile_command`; the difference is that if the instance compiles program
+ text containing a ``__future__`` statement, the instance 'remembers' and
+ compiles all subsequent program texts with the statement in force.
+
+A note on version compatibility: the :class:`Compile` and
+:class:`CommandCompiler` are new in Python 2.2. If you want to enable the
+future-tracking features of 2.2 but also retain compatibility with 2.1 and
+earlier versions of Python you can either write ::
+
+ try:
+ from codeop import CommandCompiler
+ compile_command = CommandCompiler()
+ del CommandCompiler
+ except ImportError:
+ from codeop import compile_command
+
+which is a low-impact change, but introduces possibly unwanted global state into
+your program, or you can write::
+
+ try:
+ from codeop import CommandCompiler
+ except ImportError:
+ def CommandCompiler():
+ from codeop import compile_command
+ return compile_command
+
+and then call ``CommandCompiler`` every time you need a fresh compiler object.
+
diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
new file mode 100644
index 0000000000..c2c9262160
--- /dev/null
+++ b/Doc/library/collections.rst
@@ -0,0 +1,414 @@
+
+:mod:`collections` --- High-performance container datatypes
+===========================================================
+
+.. module:: collections
+ :synopsis: High-performance datatypes
+.. moduleauthor:: Raymond Hettinger <python@rcn.com>
+.. sectionauthor:: Raymond Hettinger <python@rcn.com>
+
+
+.. versionadded:: 2.4
+
+This module implements high-performance container datatypes. Currently,
+there are two datatypes, :class:`deque` and :class:`defaultdict`, and
+one datatype factory function, :func:`NamedTuple`. Python already
+includes built-in containers, :class:`dict`, :class:`list`,
+:class:`set`, and :class:`tuple`. In addition, the optional :mod:`bsddb`
+module has a :meth:`bsddb.btopen` method that can be used to create in-memory
+or file based ordered dictionaries with string keys.
+
+Future editions of the standard library may include balanced trees and
+ordered dictionaries.
+
+.. versionchanged:: 2.5
+ Added :class:`defaultdict`.
+
+.. versionchanged:: 2.6
+ Added :class:`NamedTuple`.
+
+
+.. _deque-objects:
+
+:class:`deque` objects
+----------------------
+
+
+.. class:: deque([iterable])
+
+ Returns a new deque object initialized left-to-right (using :meth:`append`) with
+ data from *iterable*. If *iterable* is not specified, the new deque is empty.
+
+ Deques are a generalization of stacks and queues (the name is pronounced "deck"
+ and is short for "double-ended queue"). Deques support thread-safe, memory
+ efficient appends and pops from either side of the deque with approximately the
+ same O(1) performance in either direction.
+
+ Though :class:`list` objects support similar operations, they are optimized for
+ fast fixed-length operations and incur O(n) memory movement costs for
+ ``pop(0)`` and ``insert(0, v)`` operations which change both the size and
+ position of the underlying data representation.
+
+ .. versionadded:: 2.4
+
+Deque objects support the following methods:
+
+
+.. method:: deque.append(x)
+
+ Add *x* to the right side of the deque.
+
+
+.. method:: deque.appendleft(x)
+
+ Add *x* to the left side of the deque.
+
+
+.. method:: deque.clear()
+
+ Remove all elements from the deque leaving it with length 0.
+
+
+.. method:: deque.extend(iterable)
+
+ Extend the right side of the deque by appending elements from the iterable
+ argument.
+
+
+.. method:: deque.extendleft(iterable)
+
+ Extend the left side of the deque by appending elements from *iterable*. Note,
+ the series of left appends results in reversing the order of elements in the
+ iterable argument.
+
+
+.. method:: deque.pop()
+
+ Remove and return an element from the right side of the deque. If no elements
+ are present, raises an :exc:`IndexError`.
+
+
+.. method:: deque.popleft()
+
+ Remove and return an element from the left side of the deque. If no elements are
+ present, raises an :exc:`IndexError`.
+
+
+.. method:: deque.remove(value)
+
+ Removed the first occurrence of *value*. If not found, raises a
+ :exc:`ValueError`.
+
+ .. versionadded:: 2.5
+
+
+.. method:: deque.rotate(n)
+
+ Rotate the deque *n* steps to the right. If *n* is negative, rotate to the
+ left. Rotating one step to the right is equivalent to:
+ ``d.appendleft(d.pop())``.
+
+In addition to the above, deques support iteration, pickling, ``len(d)``,
+``reversed(d)``, ``copy.copy(d)``, ``copy.deepcopy(d)``, membership testing with
+the :keyword:`in` operator, and subscript references such as ``d[-1]``.
+
+Example::
+
+ >>> from collections import deque
+ >>> d = deque('ghi') # make a new deque with three items
+ >>> for elem in d: # iterate over the deque's elements
+ ... print elem.upper()
+ G
+ H
+ I
+
+ >>> d.append('j') # add a new entry to the right side
+ >>> d.appendleft('f') # add a new entry to the left side
+ >>> d # show the representation of the deque
+ deque(['f', 'g', 'h', 'i', 'j'])
+
+ >>> d.pop() # return and remove the rightmost item
+ 'j'
+ >>> d.popleft() # return and remove the leftmost item
+ 'f'
+ >>> list(d) # list the contents of the deque
+ ['g', 'h', 'i']
+ >>> d[0] # peek at leftmost item
+ 'g'
+ >>> d[-1] # peek at rightmost item
+ 'i'
+
+ >>> list(reversed(d)) # list the contents of a deque in reverse
+ ['i', 'h', 'g']
+ >>> 'h' in d # search the deque
+ True
+ >>> d.extend('jkl') # add multiple elements at once
+ >>> d
+ deque(['g', 'h', 'i', 'j', 'k', 'l'])
+ >>> d.rotate(1) # right rotation
+ >>> d
+ deque(['l', 'g', 'h', 'i', 'j', 'k'])
+ >>> d.rotate(-1) # left rotation
+ >>> d
+ deque(['g', 'h', 'i', 'j', 'k', 'l'])
+
+ >>> deque(reversed(d)) # make a new deque in reverse order
+ deque(['l', 'k', 'j', 'i', 'h', 'g'])
+ >>> d.clear() # empty the deque
+ >>> d.pop() # cannot pop from an empty deque
+ Traceback (most recent call last):
+ File "<pyshell#6>", line 1, in -toplevel-
+ d.pop()
+ IndexError: pop from an empty deque
+
+ >>> d.extendleft('abc') # extendleft() reverses the input order
+ >>> d
+ deque(['c', 'b', 'a'])
+
+
+.. _deque-recipes:
+
+Recipes
+^^^^^^^
+
+This section shows various approaches to working with deques.
+
+The :meth:`rotate` method provides a way to implement :class:`deque` slicing and
+deletion. For example, a pure python implementation of ``del d[n]`` relies on
+the :meth:`rotate` method to position elements to be popped::
+
+ def delete_nth(d, n):
+ d.rotate(-n)
+ d.popleft()
+ d.rotate(n)
+
+To implement :class:`deque` slicing, use a similar approach applying
+:meth:`rotate` to bring a target element to the left side of the deque. Remove
+old entries with :meth:`popleft`, add new entries with :meth:`extend`, and then
+reverse the rotation.
+
+With minor variations on that approach, it is easy to implement Forth style
+stack manipulations such as ``dup``, ``drop``, ``swap``, ``over``, ``pick``,
+``rot``, and ``roll``.
+
+A roundrobin task server can be built from a :class:`deque` using
+:meth:`popleft` to select the current task and :meth:`append` to add it back to
+the tasklist if the input stream is not exhausted::
+
+ >>> def roundrobin(*iterables):
+ ... pending = deque(iter(i) for i in iterables)
+ ... while pending:
+ ... task = pending.popleft()
+ ... try:
+ ... yield next(task)
+ ... except StopIteration:
+ ... continue
+ ... pending.append(task)
+ ...
+ >>> for value in roundrobin('abc', 'd', 'efgh'):
+ ... print value
+
+ a
+ d
+ e
+ b
+ f
+ c
+ g
+ h
+
+
+Multi-pass data reduction algorithms can be succinctly expressed and efficiently
+coded by extracting elements with multiple calls to :meth:`popleft`, applying
+the reduction function, and calling :meth:`append` to add the result back to the
+queue.
+
+For example, building a balanced binary tree of nested lists entails reducing
+two adjacent nodes into one by grouping them in a list::
+
+ >>> def maketree(iterable):
+ ... d = deque(iterable)
+ ... while len(d) > 1:
+ ... pair = [d.popleft(), d.popleft()]
+ ... d.append(pair)
+ ... return list(d)
+ ...
+ >>> print maketree('abcdefgh')
+ [[[['a', 'b'], ['c', 'd']], [['e', 'f'], ['g', 'h']]]]
+
+
+
+.. _defaultdict-objects:
+
+:class:`defaultdict` objects
+----------------------------
+
+
+.. class:: defaultdict([default_factory[, ...]])
+
+ Returns a new dictionary-like object. :class:`defaultdict` is a subclass of the
+ builtin :class:`dict` class. It overrides one method and adds one writable
+ instance variable. The remaining functionality is the same as for the
+ :class:`dict` class and is not documented here.
+
+ The first argument provides the initial value for the :attr:`default_factory`
+ attribute; it defaults to ``None``. All remaining arguments are treated the same
+ as if they were passed to the :class:`dict` constructor, including keyword
+ arguments.
+
+ .. versionadded:: 2.5
+
+:class:`defaultdict` objects support the following method in addition to the
+standard :class:`dict` operations:
+
+
+.. method:: defaultdict.__missing__(key)
+
+ If the :attr:`default_factory` attribute is ``None``, this raises an
+ :exc:`KeyError` exception with the *key* as argument.
+
+ If :attr:`default_factory` is not ``None``, it is called without arguments to
+ provide a default value for the given *key*, this value is inserted in the
+ dictionary for the *key*, and returned.
+
+ If calling :attr:`default_factory` raises an exception this exception is
+ propagated unchanged.
+
+ This method is called by the :meth:`__getitem__` method of the :class:`dict`
+ class when the requested key is not found; whatever it returns or raises is then
+ returned or raised by :meth:`__getitem__`.
+
+:class:`defaultdict` objects support the following instance variable:
+
+
+.. attribute:: defaultdict.default_factory
+
+ This attribute is used by the :meth:`__missing__` method; it is initialized from
+ the first argument to the constructor, if present, or to ``None``, if absent.
+
+
+.. _defaultdict-examples:
+
+:class:`defaultdict` Examples
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Using :class:`list` as the :attr:`default_factory`, it is easy to group a
+sequence of key-value pairs into a dictionary of lists::
+
+ >>> s = [('yellow', 1), ('blue', 2), ('yellow', 3), ('blue', 4), ('red', 1)]
+ >>> d = defaultdict(list)
+ >>> for k, v in s:
+ ... d[k].append(v)
+ ...
+ >>> d.items()
+ [('blue', [2, 4]), ('red', [1]), ('yellow', [1, 3])]
+
+When each key is encountered for the first time, it is not already in the
+mapping; so an entry is automatically created using the :attr:`default_factory`
+function which returns an empty :class:`list`. The :meth:`list.append`
+operation then attaches the value to the new list. When keys are encountered
+again, the look-up proceeds normally (returning the list for that key) and the
+:meth:`list.append` operation adds another value to the list. This technique is
+simpler and faster than an equivalent technique using :meth:`dict.setdefault`::
+
+ >>> d = {}
+ >>> for k, v in s:
+ ... d.setdefault(k, []).append(v)
+ ...
+ >>> d.items()
+ [('blue', [2, 4]), ('red', [1]), ('yellow', [1, 3])]
+
+Setting the :attr:`default_factory` to :class:`int` makes the
+:class:`defaultdict` useful for counting (like a bag or multiset in other
+languages)::
+
+ >>> s = 'mississippi'
+ >>> d = defaultdict(int)
+ >>> for k in s:
+ ... d[k] += 1
+ ...
+ >>> d.items()
+ [('i', 4), ('p', 2), ('s', 4), ('m', 1)]
+
+When a letter is first encountered, it is missing from the mapping, so the
+:attr:`default_factory` function calls :func:`int` to supply a default count of
+zero. The increment operation then builds up the count for each letter.
+
+The function :func:`int` which always returns zero is just a special case of
+constant functions. A faster and more flexible way to create constant functions
+is to use a lambda function which can supply any constant value (not just
+zero)::
+
+ >>> def constant_factory(value):
+ ... return lambda: value
+ >>> d = defaultdict(constant_factory('<missing>'))
+ >>> d.update(name='John', action='ran')
+ >>> '%(name)s %(action)s to %(object)s' % d
+ 'John ran to <missing>'
+
+Setting the :attr:`default_factory` to :class:`set` makes the
+:class:`defaultdict` useful for building a dictionary of sets::
+
+ >>> s = [('red', 1), ('blue', 2), ('red', 3), ('blue', 4), ('red', 1), ('blue', 4)]
+ >>> d = defaultdict(set)
+ >>> for k, v in s:
+ ... d[k].add(v)
+ ...
+ >>> d.items()
+ [('blue', set([2, 4])), ('red', set([1, 3]))]
+
+
+.. _named-tuple-factory:
+
+:func:`NamedTuple` datatype factory function
+--------------------------------------------
+
+
+.. function:: NamedTuple(typename, fieldnames)
+
+ Returns a new tuple subclass named *typename*. The new subclass is used to
+ create tuple-like objects that have fields accessable by attribute lookup as
+ well as being indexable and iterable. Instances of the subclass also have a
+ helpful docstring (with typename and fieldnames) and a helpful :meth:`__repr__`
+ method which lists the tuple contents in a ``name=value`` format.
+
+ .. versionadded:: 2.6
+
+ The *fieldnames* are specified in a single string and are separated by spaces.
+ Any valid Python identifier may be used for a field name.
+
+ Example::
+
+ >>> Point = NamedTuple('Point', 'x y')
+ >>> Point.__doc__ # docstring for the new datatype
+ 'Point(x, y)'
+ >>> p = Point(11, y=22) # instantiate with positional or keyword arguments
+ >>> p[0] + p[1] # works just like the tuple (11, 22)
+ 33
+ >>> x, y = p # unpacks just like a tuple
+ >>> x, y
+ (11, 22)
+ >>> p.x + p.y # fields also accessable by name
+ 33
+ >>> p # readable __repr__ with name=value style
+ Point(x=11, y=22)
+
+ The use cases are the same as those for tuples. The named factories assign
+ meaning to each tuple position and allow for more readable, self-documenting
+ code. Named tuples can also be used to assign field names to tuples returned
+ by the :mod:`csv` or :mod:`sqlite3` modules. For example::
+
+ from itertools import starmap
+ import csv
+ EmployeeRecord = NamedTuple('EmployeeRecord', 'name age title department paygrade')
+ for record in starmap(EmployeeRecord, csv.reader(open("employees.csv", "rb"))):
+ print record
+
+ To cast an individual record stored as :class:`list`, :class:`tuple`, or some
+ other iterable type, use the star-operator to unpack the values::
+
+ >>> Color = NamedTuple('Color', 'name code')
+ >>> m = dict(red=1, green=2, blue=3)
+ >>> print Color(*m.popitem())
+ Color(name='blue', code=3)
+
diff --git a/Doc/library/colorpicker.rst b/Doc/library/colorpicker.rst
new file mode 100644
index 0000000000..4244104c1b
--- /dev/null
+++ b/Doc/library/colorpicker.rst
@@ -0,0 +1,23 @@
+
+:mod:`ColorPicker` --- Color selection dialog
+=============================================
+
+.. module:: ColorPicker
+ :platform: Mac
+ :synopsis: Interface to the standard color selection dialog.
+.. moduleauthor:: Just van Rossum <just@letterror.com>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`ColorPicker` module provides access to the standard color picker
+dialog.
+
+
+.. function:: GetColor(prompt, rgb)
+
+ Show a standard color selection dialog and allow the user to select a color.
+ The user is given instruction by the *prompt* string, and the default color is
+ set to *rgb*. *rgb* must be a tuple giving the red, green, and blue components
+ of the color. :func:`GetColor` returns a tuple giving the user's selected color
+ and a flag indicating whether they accepted the selection of cancelled.
+
diff --git a/Doc/library/colorsys.rst b/Doc/library/colorsys.rst
new file mode 100644
index 0000000000..2e7f3b73b1
--- /dev/null
+++ b/Doc/library/colorsys.rst
@@ -0,0 +1,60 @@
+
+:mod:`colorsys` --- Conversions between color systems
+=====================================================
+
+.. module:: colorsys
+ :synopsis: Conversion functions between RGB and other color systems.
+.. sectionauthor:: David Ascher <da@python.net>
+
+
+The :mod:`colorsys` module defines bidirectional conversions of color values
+between colors expressed in the RGB (Red Green Blue) color space used in
+computer monitors and three other coordinate systems: YIQ, HLS (Hue Lightness
+Saturation) and HSV (Hue Saturation Value). Coordinates in all of these color
+spaces are floating point values. In the YIQ space, the Y coordinate is between
+0 and 1, but the I and Q coordinates can be positive or negative. In all other
+spaces, the coordinates are all between 0 and 1.
+
+More information about color spaces can be found at
+http://www.poynton.com/ColorFAQ.html.
+
+The :mod:`colorsys` module defines the following functions:
+
+
+.. function:: rgb_to_yiq(r, g, b)
+
+ Convert the color from RGB coordinates to YIQ coordinates.
+
+
+.. function:: yiq_to_rgb(y, i, q)
+
+ Convert the color from YIQ coordinates to RGB coordinates.
+
+
+.. function:: rgb_to_hls(r, g, b)
+
+ Convert the color from RGB coordinates to HLS coordinates.
+
+
+.. function:: hls_to_rgb(h, l, s)
+
+ Convert the color from HLS coordinates to RGB coordinates.
+
+
+.. function:: rgb_to_hsv(r, g, b)
+
+ Convert the color from RGB coordinates to HSV coordinates.
+
+
+.. function:: hsv_to_rgb(h, s, v)
+
+ Convert the color from HSV coordinates to RGB coordinates.
+
+Example::
+
+ >>> import colorsys
+ >>> colorsys.rgb_to_hsv(.3, .4, .2)
+ (0.25, 0.5, 0.4)
+ >>> colorsys.hsv_to_rgb(0.25, 0.5, 0.4)
+ (0.3, 0.4, 0.2)
+
diff --git a/Doc/library/commands.rst b/Doc/library/commands.rst
new file mode 100644
index 0000000000..79e3d73da7
--- /dev/null
+++ b/Doc/library/commands.rst
@@ -0,0 +1,53 @@
+
+:mod:`commands` --- Utilities for running commands
+==================================================
+
+.. module:: commands
+ :platform: Unix
+ :synopsis: Utility functions for running external commands.
+.. sectionauthor:: Sue Williams <sbw@provis.com>
+
+
+The :mod:`commands` module contains wrapper functions for :func:`os.popen` which
+take a system command as a string and return any output generated by the command
+and, optionally, the exit status.
+
+The :mod:`subprocess` module provides more powerful facilities for spawning new
+processes and retrieving their results. Using the :mod:`subprocess` module is
+preferable to using the :mod:`commands` module.
+
+The :mod:`commands` module defines the following functions:
+
+
+.. function:: getstatusoutput(cmd)
+
+ Execute the string *cmd* in a shell with :func:`os.popen` and return a 2-tuple
+ ``(status, output)``. *cmd* is actually run as ``{ cmd ; } 2>&1``, so that the
+ returned output will contain output or error messages. A trailing newline is
+ stripped from the output. The exit status for the command can be interpreted
+ according to the rules for the C function :cfunc:`wait`.
+
+
+.. function:: getoutput(cmd)
+
+ Like :func:`getstatusoutput`, except the exit status is ignored and the return
+ value is a string containing the command's output.
+
+Example::
+
+ >>> import commands
+ >>> commands.getstatusoutput('ls /bin/ls')
+ (0, '/bin/ls')
+ >>> commands.getstatusoutput('cat /bin/junk')
+ (256, 'cat: /bin/junk: No such file or directory')
+ >>> commands.getstatusoutput('/bin/junk')
+ (256, 'sh: /bin/junk: not found')
+ >>> commands.getoutput('ls /bin/ls')
+ '/bin/ls'
+
+
+.. seealso::
+
+ Module :mod:`subprocess`
+ Module for spawning and managing subprocesses.
+
diff --git a/Doc/library/compileall.rst b/Doc/library/compileall.rst
new file mode 100644
index 0000000000..d62b785dc9
--- /dev/null
+++ b/Doc/library/compileall.rst
@@ -0,0 +1,57 @@
+
+:mod:`compileall` --- Byte-compile Python libraries
+===================================================
+
+.. module:: compileall
+ :synopsis: Tools for byte-compiling all Python source files in a directory tree.
+
+
+This module provides some utility functions to support installing Python
+libraries. These functions compile Python source files in a directory tree,
+allowing users without permission to write to the libraries to take advantage of
+cached byte-code files.
+
+The source file for this module may also be used as a script to compile Python
+sources in directories named on the command line or in ``sys.path``.
+
+
+.. function:: compile_dir(dir[, maxlevels[, ddir[, force[, rx[, quiet]]]]])
+
+ Recursively descend the directory tree named by *dir*, compiling all :file:`.py`
+ files along the way. The *maxlevels* parameter is used to limit the depth of
+ the recursion; it defaults to ``10``. If *ddir* is given, it is used as the
+ base path from which the filenames used in error messages will be generated.
+ If *force* is true, modules are re-compiled even if the timestamps are up to
+ date.
+
+ If *rx* is given, it specifies a regular expression of file names to exclude
+ from the search; that expression is searched for in the full path.
+
+ If *quiet* is true, nothing is printed to the standard output in normal
+ operation.
+
+
+.. function:: compile_path([skip_curdir[, maxlevels[, force]]])
+
+ Byte-compile all the :file:`.py` files found along ``sys.path``. If
+ *skip_curdir* is true (the default), the current directory is not included in
+ the search. The *maxlevels* and *force* parameters default to ``0`` and are
+ passed to the :func:`compile_dir` function.
+
+To force a recompile of all the :file:`.py` files in the :file:`Lib/`
+subdirectory and all its subdirectories::
+
+ import compileall
+
+ compileall.compile_dir('Lib/', force=True)
+
+ # Perform same compilation, excluding files in .svn directories.
+ import re
+ compileall.compile_dir('Lib/', rx=re.compile('/[.]svn'), force=True)
+
+
+.. seealso::
+
+ Module :mod:`py_compile`
+ Byte-compile a single source file.
+
diff --git a/Doc/library/configparser.rst b/Doc/library/configparser.rst
new file mode 100644
index 0000000000..dd91d594b4
--- /dev/null
+++ b/Doc/library/configparser.rst
@@ -0,0 +1,361 @@
+
+:mod:`ConfigParser` --- Configuration file parser
+=================================================
+
+.. module:: ConfigParser
+ :synopsis: Configuration file parser.
+.. moduleauthor:: Ken Manheimer <klm@zope.com>
+.. moduleauthor:: Barry Warsaw <bwarsaw@python.org>
+.. moduleauthor:: Eric S. Raymond <esr@thyrsus.com>
+.. sectionauthor:: Christopher G. Petrilli <petrilli@amber.org>
+
+
+.. index::
+ pair: .ini; file
+ pair: configuration; file
+ single: ini file
+ single: Windows ini file
+
+This module defines the class :class:`ConfigParser`. The :class:`ConfigParser`
+class implements a basic configuration file parser language which provides a
+structure similar to what you would find on Microsoft Windows INI files. You
+can use this to write Python programs which can be customized by end users
+easily.
+
+.. warning::
+
+ This library does *not* interpret or write the value-type prefixes used in the
+ Windows Registry extended version of INI syntax.
+
+The configuration file consists of sections, led by a ``[section]`` header and
+followed by ``name: value`` entries, with continuations in the style of
+:rfc:`822`; ``name=value`` is also accepted. Note that leading whitespace is
+removed from values. The optional values can contain format strings which refer
+to other values in the same section, or values in a special ``DEFAULT`` section.
+Additional defaults can be provided on initialization and retrieval. Lines
+beginning with ``'#'`` or ``';'`` are ignored and may be used to provide
+comments.
+
+For example::
+
+ [My Section]
+ foodir: %(dir)s/whatever
+ dir=frob
+
+would resolve the ``%(dir)s`` to the value of ``dir`` (``frob`` in this case).
+All reference expansions are done on demand.
+
+Default values can be specified by passing them into the :class:`ConfigParser`
+constructor as a dictionary. Additional defaults may be passed into the
+:meth:`get` method which will override all others.
+
+Sections are normally stored in a builtin dictionary. An alternative dictionary
+type can be passed to the :class:`ConfigParser` constructor. For example, if a
+dictionary type is passed that sorts its keys, the sections will be sorted on
+write-back, as will be the keys within each section.
+
+
+.. class:: RawConfigParser([defaults[, dict_type]])
+
+ The basic configuration object. When *defaults* is given, it is initialized
+ into the dictionary of intrinsic defaults. When *dict_type* is given, it will
+ be used to create the dictionary objects for the list of sections, for the
+ options within a section, and for the default values. This class does not
+ support the magical interpolation behavior.
+
+ .. versionadded:: 2.3
+
+ .. versionchanged:: 2.6
+ *dict_type* was added.
+
+
+.. class:: ConfigParser([defaults])
+
+ Derived class of :class:`RawConfigParser` that implements the magical
+ interpolation feature and adds optional arguments to the :meth:`get` and
+ :meth:`items` methods. The values in *defaults* must be appropriate for the
+ ``%()s`` string interpolation. Note that *__name__* is an intrinsic default;
+ its value is the section name, and will override any value provided in
+ *defaults*.
+
+ All option names used in interpolation will be passed through the
+ :meth:`optionxform` method just like any other option name reference. For
+ example, using the default implementation of :meth:`optionxform` (which converts
+ option names to lower case), the values ``foo %(bar)s`` and ``foo %(BAR)s`` are
+ equivalent.
+
+
+.. class:: SafeConfigParser([defaults])
+
+ Derived class of :class:`ConfigParser` that implements a more-sane variant of
+ the magical interpolation feature. This implementation is more predictable as
+ well. New applications should prefer this version if they don't need to be
+ compatible with older versions of Python.
+
+ .. % XXX Need to explain what's safer/more predictable about it.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: NoSectionError
+
+ Exception raised when a specified section is not found.
+
+
+.. exception:: DuplicateSectionError
+
+ Exception raised if :meth:`add_section` is called with the name of a section
+ that is already present.
+
+
+.. exception:: NoOptionError
+
+ Exception raised when a specified option is not found in the specified section.
+
+
+.. exception:: InterpolationError
+
+ Base class for exceptions raised when problems occur performing string
+ interpolation.
+
+
+.. exception:: InterpolationDepthError
+
+ Exception raised when string interpolation cannot be completed because the
+ number of iterations exceeds :const:`MAX_INTERPOLATION_DEPTH`. Subclass of
+ :exc:`InterpolationError`.
+
+
+.. exception:: InterpolationMissingOptionError
+
+ Exception raised when an option referenced from a value does not exist. Subclass
+ of :exc:`InterpolationError`.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: InterpolationSyntaxError
+
+ Exception raised when the source text into which substitutions are made does not
+ conform to the required syntax. Subclass of :exc:`InterpolationError`.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: MissingSectionHeaderError
+
+ Exception raised when attempting to parse a file which has no section headers.
+
+
+.. exception:: ParsingError
+
+ Exception raised when errors occur attempting to parse a file.
+
+
+.. data:: MAX_INTERPOLATION_DEPTH
+
+ The maximum depth for recursive interpolation for :meth:`get` when the *raw*
+ parameter is false. This is relevant only for the :class:`ConfigParser` class.
+
+
+.. seealso::
+
+ Module :mod:`shlex`
+ Support for a creating Unix shell-like mini-languages which can be used as an
+ alternate format for application configuration files.
+
+
+.. _rawconfigparser-objects:
+
+RawConfigParser Objects
+-----------------------
+
+:class:`RawConfigParser` instances have the following methods:
+
+
+.. method:: RawConfigParser.defaults()
+
+ Return a dictionary containing the instance-wide defaults.
+
+
+.. method:: RawConfigParser.sections()
+
+ Return a list of the sections available; ``DEFAULT`` is not included in the
+ list.
+
+
+.. method:: RawConfigParser.add_section(section)
+
+ Add a section named *section* to the instance. If a section by the given name
+ already exists, :exc:`DuplicateSectionError` is raised.
+
+
+.. method:: RawConfigParser.has_section(section)
+
+ Indicates whether the named section is present in the configuration. The
+ ``DEFAULT`` section is not acknowledged.
+
+
+.. method:: RawConfigParser.options(section)
+
+ Returns a list of options available in the specified *section*.
+
+
+.. method:: RawConfigParser.has_option(section, option)
+
+ If the given section exists, and contains the given option, return
+ :const:`True`; otherwise return :const:`False`.
+
+ .. versionadded:: 1.6
+
+
+.. method:: RawConfigParser.read(filenames)
+
+ Attempt to read and parse a list of filenames, returning a list of filenames
+ which were successfully parsed. If *filenames* is a string or Unicode string,
+ it is treated as a single filename. If a file named in *filenames* cannot be
+ opened, that file will be ignored. This is designed so that you can specify a
+ list of potential configuration file locations (for example, the current
+ directory, the user's home directory, and some system-wide directory), and all
+ existing configuration files in the list will be read. If none of the named
+ files exist, the :class:`ConfigParser` instance will contain an empty dataset.
+ An application which requires initial values to be loaded from a file should
+ load the required file or files using :meth:`readfp` before calling :meth:`read`
+ for any optional files::
+
+ import ConfigParser, os
+
+ config = ConfigParser.ConfigParser()
+ config.readfp(open('defaults.cfg'))
+ config.read(['site.cfg', os.path.expanduser('~/.myapp.cfg')])
+
+ .. versionchanged:: 2.4
+ Returns list of successfully parsed filenames.
+
+
+.. method:: RawConfigParser.readfp(fp[, filename])
+
+ Read and parse configuration data from the file or file-like object in *fp*
+ (only the :meth:`readline` method is used). If *filename* is omitted and *fp*
+ has a :attr:`name` attribute, that is used for *filename*; the default is
+ ``<???>``.
+
+
+.. method:: RawConfigParser.get(section, option)
+
+ Get an *option* value for the named *section*.
+
+
+.. method:: RawConfigParser.getint(section, option)
+
+ A convenience method which coerces the *option* in the specified *section* to an
+ integer.
+
+
+.. method:: RawConfigParser.getfloat(section, option)
+
+ A convenience method which coerces the *option* in the specified *section* to a
+ floating point number.
+
+
+.. method:: RawConfigParser.getboolean(section, option)
+
+ A convenience method which coerces the *option* in the specified *section* to a
+ Boolean value. Note that the accepted values for the option are ``"1"``,
+ ``"yes"``, ``"true"``, and ``"on"``, which cause this method to return ``True``,
+ and ``"0"``, ``"no"``, ``"false"``, and ``"off"``, which cause it to return
+ ``False``. These string values are checked in a case-insensitive manner. Any
+ other value will cause it to raise :exc:`ValueError`.
+
+
+.. method:: RawConfigParser.items(section)
+
+ Return a list of ``(name, value)`` pairs for each option in the given *section*.
+
+
+.. method:: RawConfigParser.set(section, option, value)
+
+ If the given section exists, set the given option to the specified value;
+ otherwise raise :exc:`NoSectionError`. While it is possible to use
+ :class:`RawConfigParser` (or :class:`ConfigParser` with *raw* parameters set to
+ true) for *internal* storage of non-string values, full functionality (including
+ interpolation and output to files) can only be achieved using string values.
+
+ .. versionadded:: 1.6
+
+
+.. method:: RawConfigParser.write(fileobject)
+
+ Write a representation of the configuration to the specified file object. This
+ representation can be parsed by a future :meth:`read` call.
+
+ .. versionadded:: 1.6
+
+
+.. method:: RawConfigParser.remove_option(section, option)
+
+ Remove the specified *option* from the specified *section*. If the section does
+ not exist, raise :exc:`NoSectionError`. If the option existed to be removed,
+ return :const:`True`; otherwise return :const:`False`.
+
+ .. versionadded:: 1.6
+
+
+.. method:: RawConfigParser.remove_section(section)
+
+ Remove the specified *section* from the configuration. If the section in fact
+ existed, return ``True``. Otherwise return ``False``.
+
+
+.. method:: RawConfigParser.optionxform(option)
+
+ Transforms the option name *option* as found in an input file or as passed in by
+ client code to the form that should be used in the internal structures. The
+ default implementation returns a lower-case version of *option*; subclasses may
+ override this or client code can set an attribute of this name on instances to
+ affect this behavior. Setting this to :func:`str`, for example, would make
+ option names case sensitive.
+
+
+.. _configparser-objects:
+
+ConfigParser Objects
+--------------------
+
+The :class:`ConfigParser` class extends some methods of the
+:class:`RawConfigParser` interface, adding some optional arguments.
+
+
+.. method:: ConfigParser.get(section, option[, raw[, vars]])
+
+ Get an *option* value for the named *section*. All the ``'%'`` interpolations
+ are expanded in the return values, based on the defaults passed into the
+ constructor, as well as the options *vars* provided, unless the *raw* argument
+ is true.
+
+
+.. method:: ConfigParser.items(section[, raw[, vars]])
+
+ Return a list of ``(name, value)`` pairs for each option in the given *section*.
+ Optional arguments have the same meaning as for the :meth:`get` method.
+
+ .. versionadded:: 2.3
+
+
+.. _safeconfigparser-objects:
+
+SafeConfigParser Objects
+------------------------
+
+The :class:`SafeConfigParser` class implements the same extended interface as
+:class:`ConfigParser`, with the following addition:
+
+
+.. method:: SafeConfigParser.set(section, option, value)
+
+ If the given section exists, set the given option to the specified value;
+ otherwise raise :exc:`NoSectionError`. *value* must be a string (:class:`str`
+ or :class:`unicode`); if not, :exc:`TypeError` is raised.
+
+ .. versionadded:: 2.4
+
diff --git a/Doc/library/constants.rst b/Doc/library/constants.rst
new file mode 100644
index 0000000000..fecd8368f6
--- /dev/null
+++ b/Doc/library/constants.rst
@@ -0,0 +1,42 @@
+
+Built-in Constants
+==================
+
+A small number of constants live in the built-in namespace. They are:
+
+
+.. data:: False
+
+ The false value of the :class:`bool` type.
+
+ .. versionadded:: 2.3
+
+
+.. data:: True
+
+ The true value of the :class:`bool` type.
+
+ .. versionadded:: 2.3
+
+
+.. data:: None
+
+ The sole value of :attr:`types.NoneType`. ``None`` is frequently used to
+ represent the absence of a value, as when default arguments are not passed to a
+ function.
+
+
+.. data:: NotImplemented
+
+ Special value which can be returned by the "rich comparison" special methods
+ (:meth:`__eq__`, :meth:`__lt__`, and friends), to indicate that the comparison
+ is not implemented with respect to the other type.
+
+
+.. data:: Ellipsis
+
+ The same as ``...``. Special value used mostly in conjunction with extended
+ slicing syntax for user-defined container data types.
+
+ .. % XXX Someone who understands extended slicing should fill in here.
+
diff --git a/Doc/library/contextlib.rst b/Doc/library/contextlib.rst
new file mode 100644
index 0000000000..fffb99c86c
--- /dev/null
+++ b/Doc/library/contextlib.rst
@@ -0,0 +1,120 @@
+
+:mod:`contextlib` --- Utilities for :keyword:`with`\ -statement contexts.
+=========================================================================
+
+.. module:: contextlib
+ :synopsis: Utilities for with-statement contexts.
+
+
+.. versionadded:: 2.5
+
+This module provides utilities for common tasks involving the :keyword:`with`
+statement. For more information see also :ref:`typecontextmanager` and
+:ref:`context-managers`.
+
+Functions provided:
+
+
+.. function:: contextmanager(func)
+
+ This function is a decorator that can be used to define a factory function for
+ :keyword:`with` statement context managers, without needing to create a class or
+ separate :meth:`__enter__` and :meth:`__exit__` methods.
+
+ A simple example (this is not recommended as a real way of generating HTML!)::
+
+ from __future__ import with_statement
+ from contextlib import contextmanager
+
+ @contextmanager
+ def tag(name):
+ print "<%s>" % name
+ yield
+ print "</%s>" % name
+
+ >>> with tag("h1"):
+ ... print "foo"
+ ...
+ <h1>
+ foo
+ </h1>
+
+ The function being decorated must return a generator-iterator when called. This
+ iterator must yield exactly one value, which will be bound to the targets in the
+ :keyword:`with` statement's :keyword:`as` clause, if any.
+
+ At the point where the generator yields, the block nested in the :keyword:`with`
+ statement is executed. The generator is then resumed after the block is exited.
+ If an unhandled exception occurs in the block, it is reraised inside the
+ generator at the point where the yield occurred. Thus, you can use a
+ :keyword:`try`...\ :keyword:`except`...\ :keyword:`finally` statement to trap
+ the error (if any), or ensure that some cleanup takes place. If an exception is
+ trapped merely in order to log it or to perform some action (rather than to
+ suppress it entirely), the generator must reraise that exception. Otherwise the
+ generator context manager will indicate to the :keyword:`with` statement that
+ the exception has been handled, and execution will resume with the statement
+ immediately following the :keyword:`with` statement.
+
+
+.. function:: nested(mgr1[, mgr2[, ...]])
+
+ Combine multiple context managers into a single nested context manager.
+
+ Code like this::
+
+ from contextlib import nested
+
+ with nested(A, B, C) as (X, Y, Z):
+ do_something()
+
+ is equivalent to this::
+
+ with A as X:
+ with B as Y:
+ with C as Z:
+ do_something()
+
+ Note that if the :meth:`__exit__` method of one of the nested context managers
+ indicates an exception should be suppressed, no exception information will be
+ passed to any remaining outer context managers. Similarly, if the
+ :meth:`__exit__` method of one of the nested managers raises an exception, any
+ previous exception state will be lost; the new exception will be passed to the
+ :meth:`__exit__` methods of any remaining outer context managers. In general,
+ :meth:`__exit__` methods should avoid raising exceptions, and in particular they
+ should not re-raise a passed-in exception.
+
+
+.. function:: closing(thing)
+
+ Return a context manager that closes *thing* upon completion of the block. This
+ is basically equivalent to::
+
+ from contextlib import contextmanager
+
+ @contextmanager
+ def closing(thing):
+ try:
+ yield thing
+ finally:
+ thing.close()
+
+ And lets you write code like this::
+
+ from __future__ import with_statement
+ from contextlib import closing
+ import urllib
+
+ with closing(urllib.urlopen('http://www.python.org')) as page:
+ for line in page:
+ print line
+
+ without needing to explicitly close ``page``. Even if an error occurs,
+ ``page.close()`` will be called when the :keyword:`with` block is exited.
+
+
+.. seealso::
+
+ :pep:`0343` - The "with" statement
+ The specification, background, and examples for the Python :keyword:`with`
+ statement.
+
diff --git a/Doc/library/cookie.rst b/Doc/library/cookie.rst
new file mode 100644
index 0000000000..5a5808f1ec
--- /dev/null
+++ b/Doc/library/cookie.rst
@@ -0,0 +1,282 @@
+
+:mod:`Cookie` --- HTTP state management
+=======================================
+
+.. module:: Cookie
+ :synopsis: Support for HTTP state management (cookies).
+.. moduleauthor:: Timothy O'Malley <timo@alum.mit.edu>
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`Cookie` module defines classes for abstracting the concept of
+cookies, an HTTP state management mechanism. It supports both simple string-only
+cookies, and provides an abstraction for having any serializable data-type as
+cookie value.
+
+The module formerly strictly applied the parsing rules described in the
+:rfc:`2109` and :rfc:`2068` specifications. It has since been discovered that
+MSIE 3.0x doesn't follow the character rules outlined in those specs. As a
+result, the parsing rules used are a bit less strict.
+
+
+.. exception:: CookieError
+
+ Exception failing because of :rfc:`2109` invalidity: incorrect attributes,
+ incorrect :mailheader:`Set-Cookie` header, etc.
+
+
+.. class:: BaseCookie([input])
+
+ This class is a dictionary-like object whose keys are strings and whose values
+ are :class:`Morsel` instances. Note that upon setting a key to a value, the
+ value is first converted to a :class:`Morsel` containing the key and the value.
+
+ If *input* is given, it is passed to the :meth:`load` method.
+
+
+.. class:: SimpleCookie([input])
+
+ This class derives from :class:`BaseCookie` and overrides :meth:`value_decode`
+ and :meth:`value_encode` to be the identity and :func:`str` respectively.
+
+
+.. class:: SerialCookie([input])
+
+ This class derives from :class:`BaseCookie` and overrides :meth:`value_decode`
+ and :meth:`value_encode` to be the :func:`pickle.loads` and
+ :func:`pickle.dumps`.
+
+ .. deprecated:: 2.3
+ Reading pickled values from untrusted cookie data is a huge security hole, as
+ pickle strings can be crafted to cause arbitrary code to execute on your server.
+ It is supported for backwards compatibility only, and may eventually go away.
+
+
+.. class:: SmartCookie([input])
+
+ This class derives from :class:`BaseCookie`. It overrides :meth:`value_decode`
+ to be :func:`pickle.loads` if it is a valid pickle, and otherwise the value
+ itself. It overrides :meth:`value_encode` to be :func:`pickle.dumps` unless it
+ is a string, in which case it returns the value itself.
+
+ .. deprecated:: 2.3
+ The same security warning from :class:`SerialCookie` applies here.
+
+A further security note is warranted. For backwards compatibility, the
+:mod:`Cookie` module exports a class named :class:`Cookie` which is just an
+alias for :class:`SmartCookie`. This is probably a mistake and will likely be
+removed in a future version. You should not use the :class:`Cookie` class in
+your applications, for the same reason why you should not use the
+:class:`SerialCookie` class.
+
+
+.. seealso::
+
+ Module :mod:`cookielib`
+ HTTP cookie handling for web *clients*. The :mod:`cookielib` and :mod:`Cookie`
+ modules do not depend on each other.
+
+ :rfc:`2109` - HTTP State Management Mechanism
+ This is the state management specification implemented by this module.
+
+
+.. _cookie-objects:
+
+Cookie Objects
+--------------
+
+
+.. method:: BaseCookie.value_decode(val)
+
+ Return a decoded value from a string representation. Return value can be any
+ type. This method does nothing in :class:`BaseCookie` --- it exists so it can be
+ overridden.
+
+
+.. method:: BaseCookie.value_encode(val)
+
+ Return an encoded value. *val* can be any type, but return value must be a
+ string. This method does nothing in :class:`BaseCookie` --- it exists so it can
+ be overridden
+
+ In general, it should be the case that :meth:`value_encode` and
+ :meth:`value_decode` are inverses on the range of *value_decode*.
+
+
+.. method:: BaseCookie.output([attrs[, header[, sep]]])
+
+ Return a string representation suitable to be sent as HTTP headers. *attrs* and
+ *header* are sent to each :class:`Morsel`'s :meth:`output` method. *sep* is used
+ to join the headers together, and is by default the combination ``'\r\n'``
+ (CRLF).
+
+ .. versionchanged:: 2.5
+ The default separator has been changed from ``'\n'`` to match the cookie
+ specification.
+
+
+.. method:: BaseCookie.js_output([attrs])
+
+ Return an embeddable JavaScript snippet, which, if run on a browser which
+ supports JavaScript, will act the same as if the HTTP headers was sent.
+
+ The meaning for *attrs* is the same as in :meth:`output`.
+
+
+.. method:: BaseCookie.load(rawdata)
+
+ If *rawdata* is a string, parse it as an ``HTTP_COOKIE`` and add the values
+ found there as :class:`Morsel`\ s. If it is a dictionary, it is equivalent to::
+
+ for k, v in rawdata.items():
+ cookie[k] = v
+
+
+.. _morsel-objects:
+
+Morsel Objects
+--------------
+
+
+.. class:: Morsel()
+
+ Abstract a key/value pair, which has some :rfc:`2109` attributes.
+
+ Morsels are dictionary-like objects, whose set of keys is constant --- the valid
+ :rfc:`2109` attributes, which are
+
+ * ``expires``
+ * ``path``
+ * ``comment``
+ * ``domain``
+ * ``max-age``
+ * ``secure``
+ * ``version``
+
+ The keys are case-insensitive.
+
+
+.. attribute:: Morsel.value
+
+ The value of the cookie.
+
+
+.. attribute:: Morsel.coded_value
+
+ The encoded value of the cookie --- this is what should be sent.
+
+
+.. attribute:: Morsel.key
+
+ The name of the cookie.
+
+
+.. method:: Morsel.set(key, value, coded_value)
+
+ Set the *key*, *value* and *coded_value* members.
+
+
+.. method:: Morsel.isReservedKey(K)
+
+ Whether *K* is a member of the set of keys of a :class:`Morsel`.
+
+
+.. method:: Morsel.output([attrs[, header]])
+
+ Return a string representation of the Morsel, suitable to be sent as an HTTP
+ header. By default, all the attributes are included, unless *attrs* is given, in
+ which case it should be a list of attributes to use. *header* is by default
+ ``"Set-Cookie:"``.
+
+
+.. method:: Morsel.js_output([attrs])
+
+ Return an embeddable JavaScript snippet, which, if run on a browser which
+ supports JavaScript, will act the same as if the HTTP header was sent.
+
+ The meaning for *attrs* is the same as in :meth:`output`.
+
+
+.. method:: Morsel.OutputString([attrs])
+
+ Return a string representing the Morsel, without any surrounding HTTP or
+ JavaScript.
+
+ The meaning for *attrs* is the same as in :meth:`output`.
+
+
+.. _cookie-example:
+
+Example
+-------
+
+The following example demonstrates how to use the :mod:`Cookie` module. ::
+
+ >>> import Cookie
+ >>> C = Cookie.SimpleCookie()
+ >>> C = Cookie.SerialCookie()
+ >>> C = Cookie.SmartCookie()
+ >>> C["fig"] = "newton"
+ >>> C["sugar"] = "wafer"
+ >>> print C # generate HTTP headers
+ Set-Cookie: sugar=wafer
+ Set-Cookie: fig=newton
+ >>> print C.output() # same thing
+ Set-Cookie: sugar=wafer
+ Set-Cookie: fig=newton
+ >>> C = Cookie.SmartCookie()
+ >>> C["rocky"] = "road"
+ >>> C["rocky"]["path"] = "/cookie"
+ >>> print C.output(header="Cookie:")
+ Cookie: rocky=road; Path=/cookie
+ >>> print C.output(attrs=[], header="Cookie:")
+ Cookie: rocky=road
+ >>> C = Cookie.SmartCookie()
+ >>> C.load("chips=ahoy; vienna=finger") # load from a string (HTTP header)
+ >>> print C
+ Set-Cookie: vienna=finger
+ Set-Cookie: chips=ahoy
+ >>> C = Cookie.SmartCookie()
+ >>> C.load('keebler="E=everybody; L=\\"Loves\\"; fudge=\\012;";')
+ >>> print C
+ Set-Cookie: keebler="E=everybody; L=\"Loves\"; fudge=\012;"
+ >>> C = Cookie.SmartCookie()
+ >>> C["oreo"] = "doublestuff"
+ >>> C["oreo"]["path"] = "/"
+ >>> print C
+ Set-Cookie: oreo=doublestuff; Path=/
+ >>> C = Cookie.SmartCookie()
+ >>> C["twix"] = "none for you"
+ >>> C["twix"].value
+ 'none for you'
+ >>> C = Cookie.SimpleCookie()
+ >>> C["number"] = 7 # equivalent to C["number"] = str(7)
+ >>> C["string"] = "seven"
+ >>> C["number"].value
+ '7'
+ >>> C["string"].value
+ 'seven'
+ >>> print C
+ Set-Cookie: number=7
+ Set-Cookie: string=seven
+ >>> C = Cookie.SerialCookie()
+ >>> C["number"] = 7
+ >>> C["string"] = "seven"
+ >>> C["number"].value
+ 7
+ >>> C["string"].value
+ 'seven'
+ >>> print C
+ Set-Cookie: number="I7\012."
+ Set-Cookie: string="S'seven'\012p1\012."
+ >>> C = Cookie.SmartCookie()
+ >>> C["number"] = 7
+ >>> C["string"] = "seven"
+ >>> C["number"].value
+ 7
+ >>> C["string"].value
+ 'seven'
+ >>> print C
+ Set-Cookie: number="I7\012."
+ Set-Cookie: string=seven
+
diff --git a/Doc/library/cookielib.rst b/Doc/library/cookielib.rst
new file mode 100644
index 0000000000..44045d3d0e
--- /dev/null
+++ b/Doc/library/cookielib.rst
@@ -0,0 +1,768 @@
+
+:mod:`cookielib` --- Cookie handling for HTTP clients
+=====================================================
+
+.. module:: cookielib
+ :synopsis: Classes for automatic handling of HTTP cookies.
+.. moduleauthor:: John J. Lee <jjl@pobox.com>
+.. sectionauthor:: John J. Lee <jjl@pobox.com>
+
+
+.. versionadded:: 2.4
+
+
+
+The :mod:`cookielib` module defines classes for automatic handling of HTTP
+cookies. It is useful for accessing web sites that require small pieces of data
+-- :dfn:`cookies` -- to be set on the client machine by an HTTP response from a
+web server, and then returned to the server in later HTTP requests.
+
+Both the regular Netscape cookie protocol and the protocol defined by
+:rfc:`2965` are handled. RFC 2965 handling is switched off by default.
+:rfc:`2109` cookies are parsed as Netscape cookies and subsequently treated
+either as Netscape or RFC 2965 cookies according to the 'policy' in effect.
+Note that the great majority of cookies on the Internet are Netscape cookies.
+:mod:`cookielib` attempts to follow the de-facto Netscape cookie protocol (which
+differs substantially from that set out in the original Netscape specification),
+including taking note of the ``max-age`` and ``port`` cookie-attributes
+introduced with RFC 2965.
+
+.. note::
+
+ The various named parameters found in :mailheader:`Set-Cookie` and
+ :mailheader:`Set-Cookie2` headers (eg. ``domain`` and ``expires``) are
+ conventionally referred to as :dfn:`attributes`. To distinguish them from
+ Python attributes, the documentation for this module uses the term
+ :dfn:`cookie-attribute` instead.
+
+
+The module defines the following exception:
+
+
+.. exception:: LoadError
+
+ Instances of :class:`FileCookieJar` raise this exception on failure to load
+ cookies from a file.
+
+ .. note::
+
+ For backwards-compatibility with Python 2.4 (which raised an :exc:`IOError`),
+ :exc:`LoadError` is a subclass of :exc:`IOError`.
+
+
+The following classes are provided:
+
+
+.. class:: CookieJar(policy=None)
+
+ *policy* is an object implementing the :class:`CookiePolicy` interface.
+
+ The :class:`CookieJar` class stores HTTP cookies. It extracts cookies from HTTP
+ requests, and returns them in HTTP responses. :class:`CookieJar` instances
+ automatically expire contained cookies when necessary. Subclasses are also
+ responsible for storing and retrieving cookies from a file or database.
+
+
+.. class:: FileCookieJar(filename, delayload=None, policy=None)
+
+ *policy* is an object implementing the :class:`CookiePolicy` interface. For the
+ other arguments, see the documentation for the corresponding attributes.
+
+ A :class:`CookieJar` which can load cookies from, and perhaps save cookies to, a
+ file on disk. Cookies are **NOT** loaded from the named file until either the
+ :meth:`load` or :meth:`revert` method is called. Subclasses of this class are
+ documented in section :ref:`file-cookie-jar-classes`.
+
+
+.. class:: CookiePolicy()
+
+ This class is responsible for deciding whether each cookie should be accepted
+ from / returned to the server.
+
+
+.. class:: DefaultCookiePolicy( blocked_domains=None, allowed_domains=None, netscape=True, rfc2965=False, rfc2109_as_netscape=None, hide_cookie2=False, strict_domain=False, strict_rfc2965_unverifiable=True, strict_ns_unverifiable=False, strict_ns_domain=DefaultCookiePolicy.DomainLiberal, strict_ns_set_initial_dollar=False, strict_ns_set_path=False )
+
+ Constructor arguments should be passed as keyword arguments only.
+ *blocked_domains* is a sequence of domain names that we never accept cookies
+ from, nor return cookies to. *allowed_domains* if not :const:`None`, this is a
+ sequence of the only domains for which we accept and return cookies. For all
+ other arguments, see the documentation for :class:`CookiePolicy` and
+ :class:`DefaultCookiePolicy` objects.
+
+ :class:`DefaultCookiePolicy` implements the standard accept / reject rules for
+ Netscape and RFC 2965 cookies. By default, RFC 2109 cookies (ie. cookies
+ received in a :mailheader:`Set-Cookie` header with a version cookie-attribute of
+ 1) are treated according to the RFC 2965 rules. However, if RFC 2965 handling
+ is turned off or :attr:`rfc2109_as_netscape` is True, RFC 2109 cookies are
+ 'downgraded' by the :class:`CookieJar` instance to Netscape cookies, by
+ setting the :attr:`version` attribute of the :class:`Cookie` instance to 0.
+ :class:`DefaultCookiePolicy` also provides some parameters to allow some
+ fine-tuning of policy.
+
+
+.. class:: Cookie()
+
+ This class represents Netscape, RFC 2109 and RFC 2965 cookies. It is not
+ expected that users of :mod:`cookielib` construct their own :class:`Cookie`
+ instances. Instead, if necessary, call :meth:`make_cookies` on a
+ :class:`CookieJar` instance.
+
+
+.. seealso::
+
+ Module :mod:`urllib2`
+ URL opening with automatic cookie handling.
+
+ Module :mod:`Cookie`
+ HTTP cookie classes, principally useful for server-side code. The
+ :mod:`cookielib` and :mod:`Cookie` modules do not depend on each other.
+
+ http://wwwsearch.sf.net/ClientCookie/
+ Extensions to this module, including a class for reading Microsoft Internet
+ Explorer cookies on Windows.
+
+ http://www.netscape.com/newsref/std/cookie_spec.html
+ The specification of the original Netscape cookie protocol. Though this is
+ still the dominant protocol, the 'Netscape cookie protocol' implemented by all
+ the major browsers (and :mod:`cookielib`) only bears a passing resemblance to
+ the one sketched out in ``cookie_spec.html``.
+
+ :rfc:`2109` - HTTP State Management Mechanism
+ Obsoleted by RFC 2965. Uses :mailheader:`Set-Cookie` with version=1.
+
+ :rfc:`2965` - HTTP State Management Mechanism
+ The Netscape protocol with the bugs fixed. Uses :mailheader:`Set-Cookie2` in
+ place of :mailheader:`Set-Cookie`. Not widely used.
+
+ http://kristol.org/cookie/errata.html
+ Unfinished errata to RFC 2965.
+
+ :rfc:`2964` - Use of HTTP State Management
+
+.. _cookie-jar-objects:
+
+CookieJar and FileCookieJar Objects
+-----------------------------------
+
+:class:`CookieJar` objects support the iterator protocol for iterating over
+contained :class:`Cookie` objects.
+
+:class:`CookieJar` has the following methods:
+
+
+.. method:: CookieJar.add_cookie_header(request)
+
+ Add correct :mailheader:`Cookie` header to *request*.
+
+ If policy allows (ie. the :attr:`rfc2965` and :attr:`hide_cookie2` attributes of
+ the :class:`CookieJar`'s :class:`CookiePolicy` instance are true and false
+ respectively), the :mailheader:`Cookie2` header is also added when appropriate.
+
+ The *request* object (usually a :class:`urllib2.Request` instance) must support
+ the methods :meth:`get_full_url`, :meth:`get_host`, :meth:`get_type`,
+ :meth:`unverifiable`, :meth:`get_origin_req_host`, :meth:`has_header`,
+ :meth:`get_header`, :meth:`header_items`, and :meth:`add_unredirected_header`,as
+ documented by :mod:`urllib2`.
+
+
+.. method:: CookieJar.extract_cookies(response, request)
+
+ Extract cookies from HTTP *response* and store them in the :class:`CookieJar`,
+ where allowed by policy.
+
+ The :class:`CookieJar` will look for allowable :mailheader:`Set-Cookie` and
+ :mailheader:`Set-Cookie2` headers in the *response* argument, and store cookies
+ as appropriate (subject to the :meth:`CookiePolicy.set_ok` method's approval).
+
+ The *response* object (usually the result of a call to :meth:`urllib2.urlopen`,
+ or similar) should support an :meth:`info` method, which returns an object with
+ a :meth:`getallmatchingheaders` method (usually a :class:`mimetools.Message`
+ instance).
+
+ The *request* object (usually a :class:`urllib2.Request` instance) must support
+ the methods :meth:`get_full_url`, :meth:`get_host`, :meth:`unverifiable`, and
+ :meth:`get_origin_req_host`, as documented by :mod:`urllib2`. The request is
+ used to set default values for cookie-attributes as well as for checking that
+ the cookie is allowed to be set.
+
+
+.. method:: CookieJar.set_policy(policy)
+
+ Set the :class:`CookiePolicy` instance to be used.
+
+
+.. method:: CookieJar.make_cookies(response, request)
+
+ Return sequence of :class:`Cookie` objects extracted from *response* object.
+
+ See the documentation for :meth:`extract_cookies` for the interfaces required of
+ the *response* and *request* arguments.
+
+
+.. method:: CookieJar.set_cookie_if_ok(cookie, request)
+
+ Set a :class:`Cookie` if policy says it's OK to do so.
+
+
+.. method:: CookieJar.set_cookie(cookie)
+
+ Set a :class:`Cookie`, without checking with policy to see whether or not it
+ should be set.
+
+
+.. method:: CookieJar.clear([domain[, path[, name]]])
+
+ Clear some cookies.
+
+ If invoked without arguments, clear all cookies. If given a single argument,
+ only cookies belonging to that *domain* will be removed. If given two arguments,
+ cookies belonging to the specified *domain* and URL *path* are removed. If
+ given three arguments, then the cookie with the specified *domain*, *path* and
+ *name* is removed.
+
+ Raises :exc:`KeyError` if no matching cookie exists.
+
+
+.. method:: CookieJar.clear_session_cookies()
+
+ Discard all session cookies.
+
+ Discards all contained cookies that have a true :attr:`discard` attribute
+ (usually because they had either no ``max-age`` or ``expires`` cookie-attribute,
+ or an explicit ``discard`` cookie-attribute). For interactive browsers, the end
+ of a session usually corresponds to closing the browser window.
+
+ Note that the :meth:`save` method won't save session cookies anyway, unless you
+ ask otherwise by passing a true *ignore_discard* argument.
+
+:class:`FileCookieJar` implements the following additional methods:
+
+
+.. method:: FileCookieJar.save(filename=None, ignore_discard=False, ignore_expires=False)
+
+ Save cookies to a file.
+
+ This base class raises :exc:`NotImplementedError`. Subclasses may leave this
+ method unimplemented.
+
+ *filename* is the name of file in which to save cookies. If *filename* is not
+ specified, :attr:`self.filename` is used (whose default is the value passed to
+ the constructor, if any); if :attr:`self.filename` is :const:`None`,
+ :exc:`ValueError` is raised.
+
+ *ignore_discard*: save even cookies set to be discarded. *ignore_expires*: save
+ even cookies that have expired
+
+ The file is overwritten if it already exists, thus wiping all the cookies it
+ contains. Saved cookies can be restored later using the :meth:`load` or
+ :meth:`revert` methods.
+
+
+.. method:: FileCookieJar.load(filename=None, ignore_discard=False, ignore_expires=False)
+
+ Load cookies from a file.
+
+ Old cookies are kept unless overwritten by newly loaded ones.
+
+ Arguments are as for :meth:`save`.
+
+ The named file must be in the format understood by the class, or
+ :exc:`LoadError` will be raised. Also, :exc:`IOError` may be raised, for
+ example if the file does not exist.
+
+ .. note::
+
+ For backwards-compatibility with Python 2.4 (which raised an :exc:`IOError`),
+ :exc:`LoadError` is a subclass of :exc:`IOError`.
+
+
+.. method:: FileCookieJar.revert(filename=None, ignore_discard=False, ignore_expires=False)
+
+ Clear all cookies and reload cookies from a saved file.
+
+ :meth:`revert` can raise the same exceptions as :meth:`load`. If there is a
+ failure, the object's state will not be altered.
+
+:class:`FileCookieJar` instances have the following public attributes:
+
+
+.. attribute:: FileCookieJar.filename
+
+ Filename of default file in which to keep cookies. This attribute may be
+ assigned to.
+
+
+.. attribute:: FileCookieJar.delayload
+
+ If true, load cookies lazily from disk. This attribute should not be assigned
+ to. This is only a hint, since this only affects performance, not behaviour
+ (unless the cookies on disk are changing). A :class:`CookieJar` object may
+ ignore it. None of the :class:`FileCookieJar` classes included in the standard
+ library lazily loads cookies.
+
+
+.. _file-cookie-jar-classes:
+
+FileCookieJar subclasses and co-operation with web browsers
+-----------------------------------------------------------
+
+The following :class:`CookieJar` subclasses are provided for reading and writing
+. Further :class:`CookieJar` subclasses, including one that reads Microsoft
+Internet Explorer cookies, are available at
+http://wwwsearch.sf.net/ClientCookie/.
+
+
+.. class:: MozillaCookieJar(filename, delayload=None, policy=None)
+
+ A :class:`FileCookieJar` that can load from and save cookies to disk in the
+ Mozilla ``cookies.txt`` file format (which is also used by the Lynx and Netscape
+ browsers).
+
+ .. note::
+
+ This loses information about RFC 2965 cookies, and also about newer or
+ non-standard cookie-attributes such as ``port``.
+
+ .. warning::
+
+ Back up your cookies before saving if you have cookies whose loss / corruption
+ would be inconvenient (there are some subtleties which may lead to slight
+ changes in the file over a load / save round-trip).
+
+ Also note that cookies saved while Mozilla is running will get clobbered by
+ Mozilla.
+
+
+.. class:: LWPCookieJar(filename, delayload=None, policy=None)
+
+ A :class:`FileCookieJar` that can load from and save cookies to disk in format
+ compatible with the libwww-perl library's ``Set-Cookie3`` file format. This is
+ convenient if you want to store cookies in a human-readable file.
+
+
+.. _cookie-policy-objects:
+
+CookiePolicy Objects
+--------------------
+
+Objects implementing the :class:`CookiePolicy` interface have the following
+methods:
+
+
+.. method:: CookiePolicy.set_ok(cookie, request)
+
+ Return boolean value indicating whether cookie should be accepted from server.
+
+ *cookie* is a :class:`cookielib.Cookie` instance. *request* is an object
+ implementing the interface defined by the documentation for
+ :meth:`CookieJar.extract_cookies`.
+
+
+.. method:: CookiePolicy.return_ok(cookie, request)
+
+ Return boolean value indicating whether cookie should be returned to server.
+
+ *cookie* is a :class:`cookielib.Cookie` instance. *request* is an object
+ implementing the interface defined by the documentation for
+ :meth:`CookieJar.add_cookie_header`.
+
+
+.. method:: CookiePolicy.domain_return_ok(domain, request)
+
+ Return false if cookies should not be returned, given cookie domain.
+
+ This method is an optimization. It removes the need for checking every cookie
+ with a particular domain (which might involve reading many files). Returning
+ true from :meth:`domain_return_ok` and :meth:`path_return_ok` leaves all the
+ work to :meth:`return_ok`.
+
+ If :meth:`domain_return_ok` returns true for the cookie domain,
+ :meth:`path_return_ok` is called for the cookie path. Otherwise,
+ :meth:`path_return_ok` and :meth:`return_ok` are never called for that cookie
+ domain. If :meth:`path_return_ok` returns true, :meth:`return_ok` is called
+ with the :class:`Cookie` object itself for a full check. Otherwise,
+ :meth:`return_ok` is never called for that cookie path.
+
+ Note that :meth:`domain_return_ok` is called for every *cookie* domain, not just
+ for the *request* domain. For example, the function might be called with both
+ ``".example.com"`` and ``"www.example.com"`` if the request domain is
+ ``"www.example.com"``. The same goes for :meth:`path_return_ok`.
+
+ The *request* argument is as documented for :meth:`return_ok`.
+
+
+.. method:: CookiePolicy.path_return_ok(path, request)
+
+ Return false if cookies should not be returned, given cookie path.
+
+ See the documentation for :meth:`domain_return_ok`.
+
+In addition to implementing the methods above, implementations of the
+:class:`CookiePolicy` interface must also supply the following attributes,
+indicating which protocols should be used, and how. All of these attributes may
+be assigned to.
+
+
+.. attribute:: CookiePolicy.netscape
+
+ Implement Netscape protocol.
+
+
+.. attribute:: CookiePolicy.rfc2965
+
+ Implement RFC 2965 protocol.
+
+
+.. attribute:: CookiePolicy.hide_cookie2
+
+ Don't add :mailheader:`Cookie2` header to requests (the presence of this header
+ indicates to the server that we understand RFC 2965 cookies).
+
+The most useful way to define a :class:`CookiePolicy` class is by subclassing
+from :class:`DefaultCookiePolicy` and overriding some or all of the methods
+above. :class:`CookiePolicy` itself may be used as a 'null policy' to allow
+setting and receiving any and all cookies (this is unlikely to be useful).
+
+
+.. _default-cookie-policy-objects:
+
+DefaultCookiePolicy Objects
+---------------------------
+
+Implements the standard rules for accepting and returning cookies.
+
+Both RFC 2965 and Netscape cookies are covered. RFC 2965 handling is switched
+off by default.
+
+The easiest way to provide your own policy is to override this class and call
+its methods in your overridden implementations before adding your own additional
+checks::
+
+ import cookielib
+ class MyCookiePolicy(cookielib.DefaultCookiePolicy):
+ def set_ok(self, cookie, request):
+ if not cookielib.DefaultCookiePolicy.set_ok(self, cookie, request):
+ return False
+ if i_dont_want_to_store_this_cookie(cookie):
+ return False
+ return True
+
+In addition to the features required to implement the :class:`CookiePolicy`
+interface, this class allows you to block and allow domains from setting and
+receiving cookies. There are also some strictness switches that allow you to
+tighten up the rather loose Netscape protocol rules a little bit (at the cost of
+blocking some benign cookies).
+
+A domain blacklist and whitelist is provided (both off by default). Only domains
+not in the blacklist and present in the whitelist (if the whitelist is active)
+participate in cookie setting and returning. Use the *blocked_domains*
+constructor argument, and :meth:`blocked_domains` and
+:meth:`set_blocked_domains` methods (and the corresponding argument and methods
+for *allowed_domains*). If you set a whitelist, you can turn it off again by
+setting it to :const:`None`.
+
+Domains in block or allow lists that do not start with a dot must equal the
+cookie domain to be matched. For example, ``"example.com"`` matches a blacklist
+entry of ``"example.com"``, but ``"www.example.com"`` does not. Domains that do
+start with a dot are matched by more specific domains too. For example, both
+``"www.example.com"`` and ``"www.coyote.example.com"`` match ``".example.com"``
+(but ``"example.com"`` itself does not). IP addresses are an exception, and
+must match exactly. For example, if blocked_domains contains ``"192.168.1.2"``
+and ``".168.1.2"``, 192.168.1.2 is blocked, but 193.168.1.2 is not.
+
+:class:`DefaultCookiePolicy` implements the following additional methods:
+
+
+.. method:: DefaultCookiePolicy.blocked_domains()
+
+ Return the sequence of blocked domains (as a tuple).
+
+
+.. method:: DefaultCookiePolicy.set_blocked_domains(blocked_domains)
+
+ Set the sequence of blocked domains.
+
+
+.. method:: DefaultCookiePolicy.is_blocked(domain)
+
+ Return whether *domain* is on the blacklist for setting or receiving cookies.
+
+
+.. method:: DefaultCookiePolicy.allowed_domains()
+
+ Return :const:`None`, or the sequence of allowed domains (as a tuple).
+
+
+.. method:: DefaultCookiePolicy.set_allowed_domains(allowed_domains)
+
+ Set the sequence of allowed domains, or :const:`None`.
+
+
+.. method:: DefaultCookiePolicy.is_not_allowed(domain)
+
+ Return whether *domain* is not on the whitelist for setting or receiving
+ cookies.
+
+:class:`DefaultCookiePolicy` instances have the following attributes, which are
+all initialised from the constructor arguments of the same name, and which may
+all be assigned to.
+
+
+.. attribute:: DefaultCookiePolicy.rfc2109_as_netscape
+
+ If true, request that the :class:`CookieJar` instance downgrade RFC 2109 cookies
+ (ie. cookies received in a :mailheader:`Set-Cookie` header with a version
+ cookie-attribute of 1) to Netscape cookies by setting the version attribute of
+ the :class:`Cookie` instance to 0. The default value is :const:`None`, in which
+ case RFC 2109 cookies are downgraded if and only if RFC 2965 handling is turned
+ off. Therefore, RFC 2109 cookies are downgraded by default.
+
+ .. versionadded:: 2.5
+
+General strictness switches:
+
+
+.. attribute:: DefaultCookiePolicy.strict_domain
+
+ Don't allow sites to set two-component domains with country-code top-level
+ domains like ``.co.uk``, ``.gov.uk``, ``.co.nz``.etc. This is far from perfect
+ and isn't guaranteed to work!
+
+RFC 2965 protocol strictness switches:
+
+
+.. attribute:: DefaultCookiePolicy.strict_rfc2965_unverifiable
+
+ Follow RFC 2965 rules on unverifiable transactions (usually, an unverifiable
+ transaction is one resulting from a redirect or a request for an image hosted on
+ another site). If this is false, cookies are *never* blocked on the basis of
+ verifiability
+
+Netscape protocol strictness switches:
+
+
+.. attribute:: DefaultCookiePolicy.strict_ns_unverifiable
+
+ apply RFC 2965 rules on unverifiable transactions even to Netscape cookies
+
+
+.. attribute:: DefaultCookiePolicy.strict_ns_domain
+
+ Flags indicating how strict to be with domain-matching rules for Netscape
+ cookies. See below for acceptable values.
+
+
+.. attribute:: DefaultCookiePolicy.strict_ns_set_initial_dollar
+
+ Ignore cookies in Set-Cookie: headers that have names starting with ``'$'``.
+
+
+.. attribute:: DefaultCookiePolicy.strict_ns_set_path
+
+ Don't allow setting cookies whose path doesn't path-match request URI.
+
+:attr:`strict_ns_domain` is a collection of flags. Its value is constructed by
+or-ing together (for example, ``DomainStrictNoDots|DomainStrictNonDomain`` means
+both flags are set).
+
+
+.. attribute:: DefaultCookiePolicy.DomainStrictNoDots
+
+ When setting cookies, the 'host prefix' must not contain a dot (eg.
+ ``www.foo.bar.com`` can't set a cookie for ``.bar.com``, because ``www.foo``
+ contains a dot).
+
+
+.. attribute:: DefaultCookiePolicy.DomainStrictNonDomain
+
+ Cookies that did not explicitly specify a ``domain`` cookie-attribute can only
+ be returned to a domain equal to the domain that set the cookie (eg.
+ ``spam.example.com`` won't be returned cookies from ``example.com`` that had no
+ ``domain`` cookie-attribute).
+
+
+.. attribute:: DefaultCookiePolicy.DomainRFC2965Match
+
+ When setting cookies, require a full RFC 2965 domain-match.
+
+The following attributes are provided for convenience, and are the most useful
+combinations of the above flags:
+
+
+.. attribute:: DefaultCookiePolicy.DomainLiberal
+
+ Equivalent to 0 (ie. all of the above Netscape domain strictness flags switched
+ off).
+
+
+.. attribute:: DefaultCookiePolicy.DomainStrict
+
+ Equivalent to ``DomainStrictNoDots|DomainStrictNonDomain``.
+
+
+.. _cookielib-cookie-objects:
+
+Cookie Objects
+--------------
+
+:class:`Cookie` instances have Python attributes roughly corresponding to the
+standard cookie-attributes specified in the various cookie standards. The
+correspondence is not one-to-one, because there are complicated rules for
+assigning default values, because the ``max-age`` and ``expires``
+cookie-attributes contain equivalent information, and because RFC 2109 cookies
+may be 'downgraded' by :mod:`cookielib` from version 1 to version 0 (Netscape)
+cookies.
+
+Assignment to these attributes should not be necessary other than in rare
+circumstances in a :class:`CookiePolicy` method. The class does not enforce
+internal consistency, so you should know what you're doing if you do that.
+
+
+.. attribute:: Cookie.version
+
+ Integer or :const:`None`. Netscape cookies have :attr:`version` 0. RFC 2965 and
+ RFC 2109 cookies have a ``version`` cookie-attribute of 1. However, note that
+ :mod:`cookielib` may 'downgrade' RFC 2109 cookies to Netscape cookies, in which
+ case :attr:`version` is 0.
+
+
+.. attribute:: Cookie.name
+
+ Cookie name (a string).
+
+
+.. attribute:: Cookie.value
+
+ Cookie value (a string), or :const:`None`.
+
+
+.. attribute:: Cookie.port
+
+ String representing a port or a set of ports (eg. '80', or '80,8080'), or
+ :const:`None`.
+
+
+.. attribute:: Cookie.path
+
+ Cookie path (a string, eg. ``'/acme/rocket_launchers'``).
+
+
+.. attribute:: Cookie.secure
+
+ True if cookie should only be returned over a secure connection.
+
+
+.. attribute:: Cookie.expires
+
+ Integer expiry date in seconds since epoch, or :const:`None`. See also the
+ :meth:`is_expired` method.
+
+
+.. attribute:: Cookie.discard
+
+ True if this is a session cookie.
+
+
+.. attribute:: Cookie.comment
+
+ String comment from the server explaining the function of this cookie, or
+ :const:`None`.
+
+
+.. attribute:: Cookie.comment_url
+
+ URL linking to a comment from the server explaining the function of this cookie,
+ or :const:`None`.
+
+
+.. attribute:: Cookie.rfc2109
+
+ True if this cookie was received as an RFC 2109 cookie (ie. the cookie
+ arrived in a :mailheader:`Set-Cookie` header, and the value of the Version
+ cookie-attribute in that header was 1). This attribute is provided because
+ :mod:`cookielib` may 'downgrade' RFC 2109 cookies to Netscape cookies, in
+ which case :attr:`version` is 0.
+
+ .. versionadded:: 2.5
+
+
+.. attribute:: Cookie.port_specified
+
+ True if a port or set of ports was explicitly specified by the server (in the
+ :mailheader:`Set-Cookie` / :mailheader:`Set-Cookie2` header).
+
+
+.. attribute:: Cookie.domain_specified
+
+ True if a domain was explicitly specified by the server.
+
+
+.. attribute:: Cookie.domain_initial_dot
+
+ True if the domain explicitly specified by the server began with a dot
+ (``'.'``).
+
+Cookies may have additional non-standard cookie-attributes. These may be
+accessed using the following methods:
+
+
+.. method:: Cookie.has_nonstandard_attr(name)
+
+ Return true if cookie has the named cookie-attribute.
+
+
+.. method:: Cookie.get_nonstandard_attr(name, default=None)
+
+ If cookie has the named cookie-attribute, return its value. Otherwise, return
+ *default*.
+
+
+.. method:: Cookie.set_nonstandard_attr(name, value)
+
+ Set the value of the named cookie-attribute.
+
+The :class:`Cookie` class also defines the following method:
+
+
+.. method:: Cookie.is_expired([now=:const:`None`])
+
+ True if cookie has passed the time at which the server requested it should
+ expire. If *now* is given (in seconds since the epoch), return whether the
+ cookie has expired at the specified time.
+
+
+.. _cookielib-examples:
+
+Examples
+--------
+
+The first example shows the most common usage of :mod:`cookielib`::
+
+ import cookielib, urllib2
+ cj = cookielib.CookieJar()
+ opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
+ r = opener.open("http://example.com/")
+
+This example illustrates how to open a URL using your Netscape, Mozilla, or Lynx
+cookies (assumes Unix/Netscape convention for location of the cookies file)::
+
+ import os, cookielib, urllib2
+ cj = cookielib.MozillaCookieJar()
+ cj.load(os.path.join(os.environ["HOME"], ".netscape/cookies.txt"))
+ opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
+ r = opener.open("http://example.com/")
+
+The next example illustrates the use of :class:`DefaultCookiePolicy`. Turn on
+RFC 2965 cookies, be more strict about domains when setting and returning
+Netscape cookies, and block some domains from setting cookies or having them
+returned::
+
+ import urllib2
+ from cookielib import CookieJar, DefaultCookiePolicy
+ policy = DefaultCookiePolicy(
+ rfc2965=True, strict_ns_domain=Policy.DomainStrict,
+ blocked_domains=["ads.net", ".ads.net"])
+ cj = CookieJar(policy)
+ opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
+ r = opener.open("http://example.com/")
+
diff --git a/Doc/library/copy.rst b/Doc/library/copy.rst
new file mode 100644
index 0000000000..6fb3100679
--- /dev/null
+++ b/Doc/library/copy.rst
@@ -0,0 +1,85 @@
+
+:mod:`copy` --- Shallow and deep copy operations
+================================================
+
+.. module:: copy
+ :synopsis: Shallow and deep copy operations.
+
+
+.. index::
+ single: copy() (in copy)
+ single: deepcopy() (in copy)
+
+This module provides generic (shallow and deep) copying operations.
+
+Interface summary::
+
+ import copy
+
+ x = copy.copy(y) # make a shallow copy of y
+ x = copy.deepcopy(y) # make a deep copy of y
+
+For module specific errors, :exc:`copy.error` is raised.
+
+.. %
+
+The difference between shallow and deep copying is only relevant for compound
+objects (objects that contain other objects, like lists or class instances):
+
+* A *shallow copy* constructs a new compound object and then (to the extent
+ possible) inserts *references* into it to the objects found in the original.
+
+* A *deep copy* constructs a new compound object and then, recursively, inserts
+ *copies* into it of the objects found in the original.
+
+Two problems often exist with deep copy operations that don't exist with shallow
+copy operations:
+
+* Recursive objects (compound objects that, directly or indirectly, contain a
+ reference to themselves) may cause a recursive loop.
+
+* Because deep copy copies *everything* it may copy too much, e.g.,
+ administrative data structures that should be shared even between copies.
+
+The :func:`deepcopy` function avoids these problems by:
+
+* keeping a "memo" dictionary of objects already copied during the current
+ copying pass; and
+
+* letting user-defined classes override the copying operation or the set of
+ components copied.
+
+This module does not copy types like module, method, stack trace, stack frame,
+file, socket, window, array, or any similar types. It does "copy" functions and
+classes (shallow and deeply), by returning the original object unchanged; this
+is compatible with the way these are treated by the :mod:`pickle` module.
+
+.. versionchanged:: 2.5
+ Added copying functions.
+
+.. index:: module: pickle
+
+Classes can use the same interfaces to control copying that they use to control
+pickling. See the description of module :mod:`pickle` for information on these
+methods. The :mod:`copy` module does not use the :mod:`copy_reg` registration
+module.
+
+.. index::
+ single: __copy__() (copy protocol)
+ single: __deepcopy__() (copy protocol)
+
+In order for a class to define its own copy implementation, it can define
+special methods :meth:`__copy__` and :meth:`__deepcopy__`. The former is called
+to implement the shallow copy operation; no additional arguments are passed.
+The latter is called to implement the deep copy operation; it is passed one
+argument, the memo dictionary. If the :meth:`__deepcopy__` implementation needs
+to make a deep copy of a component, it should call the :func:`deepcopy` function
+with the component as first argument and the memo dictionary as second argument.
+
+
+.. seealso::
+
+ Module :mod:`pickle`
+ Discussion of the special methods used to support object state retrieval and
+ restoration.
+
diff --git a/Doc/library/copy_reg.rst b/Doc/library/copy_reg.rst
new file mode 100644
index 0000000000..9b82a31bac
--- /dev/null
+++ b/Doc/library/copy_reg.rst
@@ -0,0 +1,42 @@
+
+:mod:`copy_reg` --- Register :mod:`pickle` support functions
+============================================================
+
+.. module:: copy_reg
+ :synopsis: Register pickle support functions.
+
+
+.. index::
+ module: pickle
+ module: cPickle
+ module: copy
+
+The :mod:`copy_reg` module provides support for the :mod:`pickle` and
+:mod:`cPickle` modules. The :mod:`copy` module is likely to use this in the
+future as well. It provides configuration information about object constructors
+which are not classes. Such constructors may be factory functions or class
+instances.
+
+
+.. function:: constructor(object)
+
+ Declares *object* to be a valid constructor. If *object* is not callable (and
+ hence not valid as a constructor), raises :exc:`TypeError`.
+
+
+.. function:: pickle(type, function[, constructor])
+
+ Declares that *function* should be used as a "reduction" function for objects of
+ type *type*; *type* must not be a "classic" class object. (Classic classes are
+ handled differently; see the documentation for the :mod:`pickle` module for
+ details.) *function* should return either a string or a tuple containing two or
+ three elements.
+
+ The optional *constructor* parameter, if provided, is a callable object which
+ can be used to reconstruct the object when called with the tuple of arguments
+ returned by *function* at pickling time. :exc:`TypeError` will be raised if
+ *object* is a class or *constructor* is not callable.
+
+ See the :mod:`pickle` module for more details on the interface expected of
+ *function* and *constructor*.
+
diff --git a/Doc/library/crypt.rst b/Doc/library/crypt.rst
new file mode 100644
index 0000000000..8840fc7ea7
--- /dev/null
+++ b/Doc/library/crypt.rst
@@ -0,0 +1,66 @@
+
+:mod:`crypt` --- Function to check Unix passwords
+=================================================
+
+.. module:: crypt
+ :platform: Unix
+ :synopsis: The crypt() function used to check Unix passwords.
+.. moduleauthor:: Steven D. Majewski <sdm7g@virginia.edu>
+.. sectionauthor:: Steven D. Majewski <sdm7g@virginia.edu>
+.. sectionauthor:: Peter Funk <pf@artcom-gmbh.de>
+
+
+.. index::
+ single: crypt(3)
+ pair: cipher; DES
+
+This module implements an interface to the :manpage:`crypt(3)` routine, which is
+a one-way hash function based upon a modified DES algorithm; see the Unix man
+page for further details. Possible uses include allowing Python scripts to
+accept typed passwords from the user, or attempting to crack Unix passwords with
+a dictionary.
+
+.. index:: single: crypt(3)
+
+Notice that the behavior of this module depends on the actual implementation of
+the :manpage:`crypt(3)` routine in the running system. Therefore, any
+extensions available on the current implementation will also be available on
+this module.
+
+
+.. function:: crypt(word, salt)
+
+ *word* will usually be a user's password as typed at a prompt or in a graphical
+ interface. *salt* is usually a random two-character string which will be used
+ to perturb the DES algorithm in one of 4096 ways. The characters in *salt* must
+ be in the set ``[./a-zA-Z0-9]``. Returns the hashed password as a string, which
+ will be composed of characters from the same alphabet as the salt (the first two
+ characters represent the salt itself).
+
+ .. index:: single: crypt(3)
+
+ Since a few :manpage:`crypt(3)` extensions allow different values, with
+ different sizes in the *salt*, it is recommended to use the full crypted
+ password as salt when checking for a password.
+
+A simple example illustrating typical use::
+
+ import crypt, getpass, pwd
+
+ def raw_input(prompt):
+ import sys
+ sys.stdout.write(prompt)
+ sys.stdout.flush()
+ return sys.stdin.readline()
+
+ def login():
+ username = raw_input('Python login:')
+ cryptedpasswd = pwd.getpwnam(username)[1]
+ if cryptedpasswd:
+ if cryptedpasswd == 'x' or cryptedpasswd == '*':
+ raise "Sorry, currently no support for shadow passwords"
+ cleartext = getpass.getpass()
+ return crypt.crypt(cleartext, cryptedpasswd) == cryptedpasswd
+ else:
+ return 1
+
diff --git a/Doc/library/crypto.rst b/Doc/library/crypto.rst
new file mode 100644
index 0000000000..dce5a01ac6
--- /dev/null
+++ b/Doc/library/crypto.rst
@@ -0,0 +1,30 @@
+
+.. _crypto:
+
+**********************
+Cryptographic Services
+**********************
+
+.. index:: single: cryptography
+
+The modules described in this chapter implement various algorithms of a
+cryptographic nature. They are available at the discretion of the installation.
+Here's an overview:
+
+
+.. toctree::
+
+ hashlib.rst
+ hmac.rst
+
+.. index::
+ pair: AES; algorithm
+ single: cryptography
+ single: Kuchling, Andrew
+
+Hardcore cypherpunks will probably find the cryptographic modules written by
+A.M. Kuchling of further interest; the package contains modules for various
+encryption algorithms, most notably AES. These modules are not distributed with
+Python but available separately. See the URL
+http://www.amk.ca/python/code/crypto.html for more information.
+
diff --git a/Doc/library/csv.rst b/Doc/library/csv.rst
new file mode 100644
index 0000000000..19123c60f3
--- /dev/null
+++ b/Doc/library/csv.rst
@@ -0,0 +1,530 @@
+
+:mod:`csv` --- CSV File Reading and Writing
+===========================================
+
+.. module:: csv
+ :synopsis: Write and read tabular data to and from delimited files.
+.. sectionauthor:: Skip Montanaro <skip@pobox.com>
+
+
+.. versionadded:: 2.3
+
+.. index::
+ single: csv
+ pair: data; tabular
+
+The so-called CSV (Comma Separated Values) format is the most common import and
+export format for spreadsheets and databases. There is no "CSV standard", so
+the format is operationally defined by the many applications which read and
+write it. The lack of a standard means that subtle differences often exist in
+the data produced and consumed by different applications. These differences can
+make it annoying to process CSV files from multiple sources. Still, while the
+delimiters and quoting characters vary, the overall format is similar enough
+that it is possible to write a single module which can efficiently manipulate
+such data, hiding the details of reading and writing the data from the
+programmer.
+
+The :mod:`csv` module implements classes to read and write tabular data in CSV
+format. It allows programmers to say, "write this data in the format preferred
+by Excel," or "read data from this file which was generated by Excel," without
+knowing the precise details of the CSV format used by Excel. Programmers can
+also describe the CSV formats understood by other applications or define their
+own special-purpose CSV formats.
+
+The :mod:`csv` module's :class:`reader` and :class:`writer` objects read and
+write sequences. Programmers can also read and write data in dictionary form
+using the :class:`DictReader` and :class:`DictWriter` classes.
+
+.. note::
+
+ This version of the :mod:`csv` module doesn't support Unicode input. Also,
+ there are currently some issues regarding ASCII NUL characters. Accordingly,
+ all input should be UTF-8 or printable ASCII to be safe; see the examples in
+ section :ref:`csv-examples`. These restrictions will be removed in the future.
+
+
+.. seealso::
+
+ .. % \seemodule{array}{Arrays of uniformly types numeric values.}
+
+ :pep:`305` - CSV File API
+ The Python Enhancement Proposal which proposed this addition to Python.
+
+
+.. _csv-contents:
+
+Module Contents
+---------------
+
+The :mod:`csv` module defines the following functions:
+
+
+.. function:: reader(csvfile[, dialect='excel'][, fmtparam])
+
+ Return a reader object which will iterate over lines in the given *csvfile*.
+ *csvfile* can be any object which supports the iterator protocol and returns a
+ string each time its :meth:`next` method is called --- file objects and list
+ objects are both suitable. If *csvfile* is a file object, it must be opened
+ with the 'b' flag on platforms where that makes a difference. An optional
+ *dialect* parameter can be given which is used to define a set of parameters
+ specific to a particular CSV dialect. It may be an instance of a subclass of
+ the :class:`Dialect` class or one of the strings returned by the
+ :func:`list_dialects` function. The other optional *fmtparam* keyword arguments
+ can be given to override individual formatting parameters in the current
+ dialect. For full details about the dialect and formatting parameters, see
+ section :ref:`csv-fmt-params`.
+
+ All data read are returned as strings. No automatic data type conversion is
+ performed.
+
+ .. versionchanged:: 2.5
+ The parser is now stricter with respect to multi-line quoted fields. Previously,
+ if a line ended within a quoted field without a terminating newline character, a
+ newline would be inserted into the returned field. This behavior caused problems
+ when reading files which contained carriage return characters within fields.
+ The behavior was changed to return the field without inserting newlines. As a
+ consequence, if newlines embedded within fields are important, the input should
+ be split into lines in a manner which preserves the newline characters.
+
+
+.. function:: writer(csvfile[, dialect='excel'][, fmtparam])
+
+ Return a writer object responsible for converting the user's data into delimited
+ strings on the given file-like object. *csvfile* can be any object with a
+ :func:`write` method. If *csvfile* is a file object, it must be opened with the
+ 'b' flag on platforms where that makes a difference. An optional *dialect*
+ parameter can be given which is used to define a set of parameters specific to a
+ particular CSV dialect. It may be an instance of a subclass of the
+ :class:`Dialect` class or one of the strings returned by the
+ :func:`list_dialects` function. The other optional *fmtparam* keyword arguments
+ can be given to override individual formatting parameters in the current
+ dialect. For full details about the dialect and formatting parameters, see
+ section :ref:`csv-fmt-params`. To make it
+ as easy as possible to interface with modules which implement the DB API, the
+ value :const:`None` is written as the empty string. While this isn't a
+ reversible transformation, it makes it easier to dump SQL NULL data values to
+ CSV files without preprocessing the data returned from a ``cursor.fetch*`` call.
+ All other non-string data are stringified with :func:`str` before being written.
+
+
+.. function:: register_dialect(name[, dialect][, fmtparam])
+
+ Associate *dialect* with *name*. *name* must be a string or Unicode object. The
+ dialect can be specified either by passing a sub-class of :class:`Dialect`, or
+ by *fmtparam* keyword arguments, or both, with keyword arguments overriding
+ parameters of the dialect. For full details about the dialect and formatting
+ parameters, see section :ref:`csv-fmt-params`.
+
+
+.. function:: unregister_dialect(name)
+
+ Delete the dialect associated with *name* from the dialect registry. An
+ :exc:`Error` is raised if *name* is not a registered dialect name.
+
+
+.. function:: get_dialect(name)
+
+ Return the dialect associated with *name*. An :exc:`Error` is raised if *name*
+ is not a registered dialect name.
+
+
+.. function:: list_dialects()
+
+ Return the names of all registered dialects.
+
+
+.. function:: field_size_limit([new_limit])
+
+ Returns the current maximum field size allowed by the parser. If *new_limit* is
+ given, this becomes the new limit.
+
+ .. versionadded:: 2.5
+
+The :mod:`csv` module defines the following classes:
+
+
+.. class:: DictReader(csvfile[, fieldnames=:const:None,[, restkey=:const:None[, restval=None[, dialect='excel'[, *args, **kwds]]]]])
+
+ Create an object which operates like a regular reader but maps the information
+ read into a dict whose keys are given by the optional *fieldnames* parameter.
+ If the *fieldnames* parameter is omitted, the values in the first row of the
+ *csvfile* will be used as the fieldnames. If the row read has fewer fields than
+ the fieldnames sequence, the value of *restval* will be used as the default
+ value. If the row read has more fields than the fieldnames sequence, the
+ remaining data is added as a sequence keyed by the value of *restkey*. If the
+ row read has fewer fields than the fieldnames sequence, the remaining keys take
+ the value of the optional *restval* parameter. Any other optional or keyword
+ arguments are passed to the underlying :class:`reader` instance.
+
+
+.. class:: DictWriter(csvfile, fieldnames[, restval=''[, extrasaction='raise'[, dialect='excel'[, *args, **kwds]]]])
+
+ Create an object which operates like a regular writer but maps dictionaries onto
+ output rows. The *fieldnames* parameter identifies the order in which values in
+ the dictionary passed to the :meth:`writerow` method are written to the
+ *csvfile*. The optional *restval* parameter specifies the value to be written
+ if the dictionary is missing a key in *fieldnames*. If the dictionary passed to
+ the :meth:`writerow` method contains a key not found in *fieldnames*, the
+ optional *extrasaction* parameter indicates what action to take. If it is set
+ to ``'raise'`` a :exc:`ValueError` is raised. If it is set to ``'ignore'``,
+ extra values in the dictionary are ignored. Any other optional or keyword
+ arguments are passed to the underlying :class:`writer` instance.
+
+ Note that unlike the :class:`DictReader` class, the *fieldnames* parameter of
+ the :class:`DictWriter` is not optional. Since Python's :class:`dict` objects
+ are not ordered, there is not enough information available to deduce the order
+ in which the row should be written to the *csvfile*.
+
+
+.. class:: Dialect
+
+ The :class:`Dialect` class is a container class relied on primarily for its
+ attributes, which are used to define the parameters for a specific
+ :class:`reader` or :class:`writer` instance.
+
+
+.. class:: excel()
+
+ The :class:`excel` class defines the usual properties of an Excel-generated CSV
+ file. It is registered with the dialect name ``'excel'``.
+
+
+.. class:: excel_tab()
+
+ The :class:`excel_tab` class defines the usual properties of an Excel-generated
+ TAB-delimited file. It is registered with the dialect name ``'excel-tab'``.
+
+
+.. class:: Sniffer()
+
+ The :class:`Sniffer` class is used to deduce the format of a CSV file.
+
+The :class:`Sniffer` class provides two methods:
+
+
+.. method:: Sniffer.sniff(sample[, delimiters=None])
+
+ Analyze the given *sample* and return a :class:`Dialect` subclass reflecting the
+ parameters found. If the optional *delimiters* parameter is given, it is
+ interpreted as a string containing possible valid delimiter characters.
+
+
+.. method:: Sniffer.has_header(sample)
+
+ Analyze the sample text (presumed to be in CSV format) and return :const:`True`
+ if the first row appears to be a series of column headers.
+
+The :mod:`csv` module defines the following constants:
+
+
+.. data:: QUOTE_ALL
+
+ Instructs :class:`writer` objects to quote all fields.
+
+
+.. data:: QUOTE_MINIMAL
+
+ Instructs :class:`writer` objects to only quote those fields which contain
+ special characters such as *delimiter*, *quotechar* or any of the characters in
+ *lineterminator*.
+
+
+.. data:: QUOTE_NONNUMERIC
+
+ Instructs :class:`writer` objects to quote all non-numeric fields.
+
+ Instructs the reader to convert all non-quoted fields to type *float*.
+
+
+.. data:: QUOTE_NONE
+
+ Instructs :class:`writer` objects to never quote fields. When the current
+ *delimiter* occurs in output data it is preceded by the current *escapechar*
+ character. If *escapechar* is not set, the writer will raise :exc:`Error` if
+ any characters that require escaping are encountered.
+
+ Instructs :class:`reader` to perform no special processing of quote characters.
+
+The :mod:`csv` module defines the following exception:
+
+
+.. exception:: Error
+
+ Raised by any of the functions when an error is detected.
+
+
+.. _csv-fmt-params:
+
+Dialects and Formatting Parameters
+----------------------------------
+
+To make it easier to specify the format of input and output records, specific
+formatting parameters are grouped together into dialects. A dialect is a
+subclass of the :class:`Dialect` class having a set of specific methods and a
+single :meth:`validate` method. When creating :class:`reader` or
+:class:`writer` objects, the programmer can specify a string or a subclass of
+the :class:`Dialect` class as the dialect parameter. In addition to, or instead
+of, the *dialect* parameter, the programmer can also specify individual
+formatting parameters, which have the same names as the attributes defined below
+for the :class:`Dialect` class.
+
+Dialects support the following attributes:
+
+
+.. attribute:: Dialect.delimiter
+
+ A one-character string used to separate fields. It defaults to ``','``.
+
+
+.. attribute:: Dialect.doublequote
+
+ Controls how instances of *quotechar* appearing inside a field should be
+ themselves be quoted. When :const:`True`, the character is doubled. When
+ :const:`False`, the *escapechar* is used as a prefix to the *quotechar*. It
+ defaults to :const:`True`.
+
+ On output, if *doublequote* is :const:`False` and no *escapechar* is set,
+ :exc:`Error` is raised if a *quotechar* is found in a field.
+
+
+.. attribute:: Dialect.escapechar
+
+ A one-character string used by the writer to escape the *delimiter* if *quoting*
+ is set to :const:`QUOTE_NONE` and the *quotechar* if *doublequote* is
+ :const:`False`. On reading, the *escapechar* removes any special meaning from
+ the following character. It defaults to :const:`None`, which disables escaping.
+
+
+.. attribute:: Dialect.lineterminator
+
+ The string used to terminate lines produced by the :class:`writer`. It defaults
+ to ``'\r\n'``.
+
+ .. note::
+
+ The :class:`reader` is hard-coded to recognise either ``'\r'`` or ``'\n'`` as
+ end-of-line, and ignores *lineterminator*. This behavior may change in the
+ future.
+
+
+.. attribute:: Dialect.quotechar
+
+ A one-character string used to quote fields containing special characters, such
+ as the *delimiter* or *quotechar*, or which contain new-line characters. It
+ defaults to ``'"'``.
+
+
+.. attribute:: Dialect.quoting
+
+ Controls when quotes should be generated by the writer and recognised by the
+ reader. It can take on any of the :const:`QUOTE_\*` constants (see section
+ :ref:`csv-contents`) and defaults to :const:`QUOTE_MINIMAL`.
+
+
+.. attribute:: Dialect.skipinitialspace
+
+ When :const:`True`, whitespace immediately following the *delimiter* is ignored.
+ The default is :const:`False`.
+
+
+Reader Objects
+--------------
+
+Reader objects (:class:`DictReader` instances and objects returned by the
+:func:`reader` function) have the following public methods:
+
+
+.. method:: csvreader.next()
+
+ Return the next row of the reader's iterable object as a list, parsed according
+ to the current dialect.
+
+Reader objects have the following public attributes:
+
+
+.. attribute:: csvreader.dialect
+
+ A read-only description of the dialect in use by the parser.
+
+
+.. attribute:: csvreader.line_num
+
+ The number of lines read from the source iterator. This is not the same as the
+ number of records returned, as records can span multiple lines.
+
+ .. versionadded:: 2.5
+
+
+Writer Objects
+--------------
+
+:class:`Writer` objects (:class:`DictWriter` instances and objects returned by
+the :func:`writer` function) have the following public methods. A *row* must be
+a sequence of strings or numbers for :class:`Writer` objects and a dictionary
+mapping fieldnames to strings or numbers (by passing them through :func:`str`
+first) for :class:`DictWriter` objects. Note that complex numbers are written
+out surrounded by parens. This may cause some problems for other programs which
+read CSV files (assuming they support complex numbers at all).
+
+
+.. method:: csvwriter.writerow(row)
+
+ Write the *row* parameter to the writer's file object, formatted according to
+ the current dialect.
+
+
+.. method:: csvwriter.writerows(rows)
+
+ Write all the *rows* parameters (a list of *row* objects as described above) to
+ the writer's file object, formatted according to the current dialect.
+
+Writer objects have the following public attribute:
+
+
+.. attribute:: csvwriter.dialect
+
+ A read-only description of the dialect in use by the writer.
+
+
+.. _csv-examples:
+
+Examples
+--------
+
+The simplest example of reading a CSV file::
+
+ import csv
+ reader = csv.reader(open("some.csv", "rb"))
+ for row in reader:
+ print row
+
+Reading a file with an alternate format::
+
+ import csv
+ reader = csv.reader(open("passwd", "rb"), delimiter=':', quoting=csv.QUOTE_NONE)
+ for row in reader:
+ print row
+
+The corresponding simplest possible writing example is::
+
+ import csv
+ writer = csv.writer(open("some.csv", "wb"))
+ writer.writerows(someiterable)
+
+Registering a new dialect::
+
+ import csv
+
+ csv.register_dialect('unixpwd', delimiter=':', quoting=csv.QUOTE_NONE)
+
+ reader = csv.reader(open("passwd", "rb"), 'unixpwd')
+
+A slightly more advanced use of the reader --- catching and reporting errors::
+
+ import csv, sys
+ filename = "some.csv"
+ reader = csv.reader(open(filename, "rb"))
+ try:
+ for row in reader:
+ print row
+ except csv.Error as e:
+ sys.exit('file %s, line %d: %s' % (filename, reader.line_num, e))
+
+And while the module doesn't directly support parsing strings, it can easily be
+done::
+
+ import csv
+ for row in csv.reader(['one,two,three']):
+ print row
+
+The :mod:`csv` module doesn't directly support reading and writing Unicode, but
+it is 8-bit-clean save for some problems with ASCII NUL characters. So you can
+write functions or classes that handle the encoding and decoding for you as long
+as you avoid encodings like UTF-16 that use NULs. UTF-8 is recommended.
+
+:func:`unicode_csv_reader` below is a generator that wraps :class:`csv.reader`
+to handle Unicode CSV data (a list of Unicode strings). :func:`utf_8_encoder`
+is a generator that encodes the Unicode strings as UTF-8, one string (or row) at
+a time. The encoded strings are parsed by the CSV reader, and
+:func:`unicode_csv_reader` decodes the UTF-8-encoded cells back into Unicode::
+
+ import csv
+
+ def unicode_csv_reader(unicode_csv_data, dialect=csv.excel, **kwargs):
+ # csv.py doesn't do Unicode; encode temporarily as UTF-8:
+ csv_reader = csv.reader(utf_8_encoder(unicode_csv_data),
+ dialect=dialect, **kwargs)
+ for row in csv_reader:
+ # decode UTF-8 back to Unicode, cell by cell:
+ yield [unicode(cell, 'utf-8') for cell in row]
+
+ def utf_8_encoder(unicode_csv_data):
+ for line in unicode_csv_data:
+ yield line.encode('utf-8')
+
+For all other encodings the following :class:`UnicodeReader` and
+:class:`UnicodeWriter` classes can be used. They take an additional *encoding*
+parameter in their constructor and make sure that the data passes the real
+reader or writer encoded as UTF-8::
+
+ import csv, codecs, cStringIO
+
+ class UTF8Recoder:
+ """
+ Iterator that reads an encoded stream and reencodes the input to UTF-8
+ """
+ def __init__(self, f, encoding):
+ self.reader = codecs.getreader(encoding)(f)
+
+ def __iter__(self):
+ return self
+
+ def __next__(self):
+ return next(self.reader).encode("utf-8")
+
+ class UnicodeReader:
+ """
+ A CSV reader which will iterate over lines in the CSV file "f",
+ which is encoded in the given encoding.
+ """
+
+ def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
+ f = UTF8Recoder(f, encoding)
+ self.reader = csv.reader(f, dialect=dialect, **kwds)
+
+ def __next__(self):
+ row = next(self.reader)
+ return [unicode(s, "utf-8") for s in row]
+
+ def __iter__(self):
+ return self
+
+ class UnicodeWriter:
+ """
+ A CSV writer which will write rows to CSV file "f",
+ which is encoded in the given encoding.
+ """
+
+ def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
+ # Redirect output to a queue
+ self.queue = cStringIO.StringIO()
+ self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
+ self.stream = f
+ self.encoder = codecs.getincrementalencoder(encoding)()
+
+ def writerow(self, row):
+ self.writer.writerow([s.encode("utf-8") for s in row])
+ # Fetch UTF-8 output from the queue ...
+ data = self.queue.getvalue()
+ data = data.decode("utf-8")
+ # ... and reencode it into the target encoding
+ data = self.encoder.encode(data)
+ # write to the target stream
+ self.stream.write(data)
+ # empty queue
+ self.queue.truncate(0)
+
+ def writerows(self, rows):
+ for row in rows:
+ self.writerow(row)
+
diff --git a/Doc/library/ctypes.rst b/Doc/library/ctypes.rst
new file mode 100644
index 0000000000..dc375654a0
--- /dev/null
+++ b/Doc/library/ctypes.rst
@@ -0,0 +1,2364 @@
+
+:mod:`ctypes` --- A foreign function library for Python.
+========================================================
+
+.. module:: ctypes
+ :synopsis: A foreign function library for Python.
+.. moduleauthor:: Thomas Heller <theller@python.net>
+
+
+.. versionadded:: 2.5
+
+``ctypes`` is a foreign function library for Python. It provides C compatible
+data types, and allows calling functions in dlls/shared libraries. It can be
+used to wrap these libraries in pure Python.
+
+
+.. _ctypes-ctypes-tutorial:
+
+ctypes tutorial
+---------------
+
+Note: The code samples in this tutorial use ``doctest`` to make sure that they
+actually work. Since some code samples behave differently under Linux, Windows,
+or Mac OS X, they contain doctest directives in comments.
+
+Note: Some code sample references the ctypes :class:`c_int` type. This type is
+an alias to the :class:`c_long` type on 32-bit systems. So, you should not be
+confused if :class:`c_long` is printed if you would expect :class:`c_int` ---
+they are actually the same type.
+
+
+.. _ctypes-loading-dynamic-link-libraries:
+
+Loading dynamic link libraries
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+``ctypes`` exports the *cdll*, and on Windows also *windll* and *oledll* objects
+to load dynamic link libraries.
+
+You load libraries by accessing them as attributes of these objects. *cdll*
+loads libraries which export functions using the standard ``cdecl`` calling
+convention, while *windll* libraries call functions using the ``stdcall``
+calling convention. *oledll* also uses the ``stdcall`` calling convention, and
+assumes the functions return a Windows :class:`HRESULT` error code. The error
+code is used to automatically raise :class:`WindowsError` Python exceptions when
+the function call fails.
+
+Here are some examples for Windows. Note that ``msvcrt`` is the MS standard C
+library containing most standard C functions, and uses the cdecl calling
+convention::
+
+ >>> from ctypes import *
+ >>> print windll.kernel32 # doctest: +WINDOWS
+ <WinDLL 'kernel32', handle ... at ...>
+ >>> print cdll.msvcrt # doctest: +WINDOWS
+ <CDLL 'msvcrt', handle ... at ...>
+ >>> libc = cdll.msvcrt # doctest: +WINDOWS
+ >>>
+
+Windows appends the usual '.dll' file suffix automatically.
+
+On Linux, it is required to specify the filename *including* the extension to
+load a library, so attribute access does not work. Either the
+:meth:`LoadLibrary` method of the dll loaders should be used, or you should load
+the library by creating an instance of CDLL by calling the constructor::
+
+ >>> cdll.LoadLibrary("libc.so.6") # doctest: +LINUX
+ <CDLL 'libc.so.6', handle ... at ...>
+ >>> libc = CDLL("libc.so.6") # doctest: +LINUX
+ >>> libc # doctest: +LINUX
+ <CDLL 'libc.so.6', handle ... at ...>
+ >>>
+
+.. % XXX Add section for Mac OS X.
+
+
+.. _ctypes-accessing-functions-from-loaded-dlls:
+
+Accessing functions from loaded dlls
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Functions are accessed as attributes of dll objects::
+
+ >>> from ctypes import *
+ >>> libc.printf
+ <_FuncPtr object at 0x...>
+ >>> print windll.kernel32.GetModuleHandleA # doctest: +WINDOWS
+ <_FuncPtr object at 0x...>
+ >>> print windll.kernel32.MyOwnFunction # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "ctypes.py", line 239, in __getattr__
+ func = _StdcallFuncPtr(name, self)
+ AttributeError: function 'MyOwnFunction' not found
+ >>>
+
+Note that win32 system dlls like ``kernel32`` and ``user32`` often export ANSI
+as well as UNICODE versions of a function. The UNICODE version is exported with
+an ``W`` appended to the name, while the ANSI version is exported with an ``A``
+appended to the name. The win32 ``GetModuleHandle`` function, which returns a
+*module handle* for a given module name, has the following C prototype, and a
+macro is used to expose one of them as ``GetModuleHandle`` depending on whether
+UNICODE is defined or not::
+
+ /* ANSI version */
+ HMODULE GetModuleHandleA(LPCSTR lpModuleName);
+ /* UNICODE version */
+ HMODULE GetModuleHandleW(LPCWSTR lpModuleName);
+
+*windll* does not try to select one of them by magic, you must access the
+version you need by specifying ``GetModuleHandleA`` or ``GetModuleHandleW``
+explicitely, and then call it with normal strings or unicode strings
+respectively.
+
+Sometimes, dlls export functions with names which aren't valid Python
+identifiers, like ``"??2@YAPAXI@Z"``. In this case you have to use ``getattr``
+to retrieve the function::
+
+ >>> getattr(cdll.msvcrt, "??2@YAPAXI@Z") # doctest: +WINDOWS
+ <_FuncPtr object at 0x...>
+ >>>
+
+On Windows, some dlls export functions not by name but by ordinal. These
+functions can be accessed by indexing the dll object with the ordinal number::
+
+ >>> cdll.kernel32[1] # doctest: +WINDOWS
+ <_FuncPtr object at 0x...>
+ >>> cdll.kernel32[0] # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "ctypes.py", line 310, in __getitem__
+ func = _StdcallFuncPtr(name, self)
+ AttributeError: function ordinal 0 not found
+ >>>
+
+
+.. _ctypes-calling-functions:
+
+Calling functions
+^^^^^^^^^^^^^^^^^
+
+You can call these functions like any other Python callable. This example uses
+the ``time()`` function, which returns system time in seconds since the Unix
+epoch, and the ``GetModuleHandleA()`` function, which returns a win32 module
+handle.
+
+This example calls both functions with a NULL pointer (``None`` should be used
+as the NULL pointer)::
+
+ >>> print libc.time(None) # doctest: +SKIP
+ 1150640792
+ >>> print hex(windll.kernel32.GetModuleHandleA(None)) # doctest: +WINDOWS
+ 0x1d000000
+ >>>
+
+``ctypes`` tries to protect you from calling functions with the wrong number of
+arguments or the wrong calling convention. Unfortunately this only works on
+Windows. It does this by examining the stack after the function returns, so
+although an error is raised the function *has* been called::
+
+ >>> windll.kernel32.GetModuleHandleA() # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: Procedure probably called with not enough arguments (4 bytes missing)
+ >>> windll.kernel32.GetModuleHandleA(0, 0) # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: Procedure probably called with too many arguments (4 bytes in excess)
+ >>>
+
+The same exception is raised when you call an ``stdcall`` function with the
+``cdecl`` calling convention, or vice versa::
+
+ >>> cdll.kernel32.GetModuleHandleA(None) # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: Procedure probably called with not enough arguments (4 bytes missing)
+ >>>
+
+ >>> windll.msvcrt.printf("spam") # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: Procedure probably called with too many arguments (4 bytes in excess)
+ >>>
+
+To find out the correct calling convention you have to look into the C header
+file or the documentation for the function you want to call.
+
+On Windows, ``ctypes`` uses win32 structured exception handling to prevent
+crashes from general protection faults when functions are called with invalid
+argument values::
+
+ >>> windll.kernel32.GetModuleHandleA(32) # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ WindowsError: exception: access violation reading 0x00000020
+ >>>
+
+There are, however, enough ways to crash Python with ``ctypes``, so you should
+be careful anyway.
+
+``None``, integers, longs, byte strings and unicode strings are the only native
+Python objects that can directly be used as parameters in these function calls.
+``None`` is passed as a C ``NULL`` pointer, byte strings and unicode strings are
+passed as pointer to the memory block that contains their data (``char *`` or
+``wchar_t *``). Python integers and Python longs are passed as the platforms
+default C ``int`` type, their value is masked to fit into the C type.
+
+Before we move on calling functions with other parameter types, we have to learn
+more about ``ctypes`` data types.
+
+
+.. _ctypes-fundamental-data-types:
+
+Fundamental data types
+^^^^^^^^^^^^^^^^^^^^^^
+
+``ctypes`` defines a number of primitive C compatible data types :
+
+ +----------------------+--------------------------------+----------------------------+
+ | ctypes type | C type | Python type |
+ +======================+================================+============================+
+ | :class:`c_char` | ``char`` | 1-character string |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_wchar` | ``wchar_t`` | 1-character unicode string |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_byte` | ``char`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_ubyte` | ``unsigned char`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_short` | ``short`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_ushort` | ``unsigned short`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_int` | ``int`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_uint` | ``unsigned int`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_long` | ``long`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_ulong` | ``unsigned long`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_longlong` | ``__int64`` or ``long long`` | int/long |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_ulonglong` | ``unsigned __int64`` or | int/long |
+ | | ``unsigned long long`` | |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_float` | ``float`` | float |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_double` | ``double`` | float |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_char_p` | ``char *`` (NUL terminated) | string or ``None`` |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_wchar_p` | ``wchar_t *`` (NUL terminated) | unicode or ``None`` |
+ +----------------------+--------------------------------+----------------------------+
+ | :class:`c_void_p` | ``void *`` | int/long or ``None`` |
+ +----------------------+--------------------------------+----------------------------+
+
+
+All these types can be created by calling them with an optional initializer of
+the correct type and value::
+
+ >>> c_int()
+ c_long(0)
+ >>> c_char_p("Hello, World")
+ c_char_p('Hello, World')
+ >>> c_ushort(-3)
+ c_ushort(65533)
+ >>>
+
+Since these types are mutable, their value can also be changed afterwards::
+
+ >>> i = c_int(42)
+ >>> print i
+ c_long(42)
+ >>> print i.value
+ 42
+ >>> i.value = -99
+ >>> print i.value
+ -99
+ >>>
+
+Assigning a new value to instances of the pointer types :class:`c_char_p`,
+:class:`c_wchar_p`, and :class:`c_void_p` changes the *memory location* they
+point to, *not the contents* of the memory block (of course not, because Python
+strings are immutable)::
+
+ >>> s = "Hello, World"
+ >>> c_s = c_char_p(s)
+ >>> print c_s
+ c_char_p('Hello, World')
+ >>> c_s.value = "Hi, there"
+ >>> print c_s
+ c_char_p('Hi, there')
+ >>> print s # first string is unchanged
+ Hello, World
+ >>>
+
+You should be careful, however, not to pass them to functions expecting pointers
+to mutable memory. If you need mutable memory blocks, ctypes has a
+``create_string_buffer`` function which creates these in various ways. The
+current memory block contents can be accessed (or changed) with the ``raw``
+property; if you want to access it as NUL terminated string, use the ``value``
+property::
+
+ >>> from ctypes import *
+ >>> p = create_string_buffer(3) # create a 3 byte buffer, initialized to NUL bytes
+ >>> print sizeof(p), repr(p.raw)
+ 3 '\x00\x00\x00'
+ >>> p = create_string_buffer("Hello") # create a buffer containing a NUL terminated string
+ >>> print sizeof(p), repr(p.raw)
+ 6 'Hello\x00'
+ >>> print repr(p.value)
+ 'Hello'
+ >>> p = create_string_buffer("Hello", 10) # create a 10 byte buffer
+ >>> print sizeof(p), repr(p.raw)
+ 10 'Hello\x00\x00\x00\x00\x00'
+ >>> p.value = "Hi"
+ >>> print sizeof(p), repr(p.raw)
+ 10 'Hi\x00lo\x00\x00\x00\x00\x00'
+ >>>
+
+The ``create_string_buffer`` function replaces the ``c_buffer`` function (which
+is still available as an alias), as well as the ``c_string`` function from
+earlier ctypes releases. To create a mutable memory block containing unicode
+characters of the C type ``wchar_t`` use the ``create_unicode_buffer`` function.
+
+
+.. _ctypes-calling-functions-continued:
+
+Calling functions, continued
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Note that printf prints to the real standard output channel, *not* to
+``sys.stdout``, so these examples will only work at the console prompt, not from
+within *IDLE* or *PythonWin*::
+
+ >>> printf = libc.printf
+ >>> printf("Hello, %s\n", "World!")
+ Hello, World!
+ 14
+ >>> printf("Hello, %S", u"World!")
+ Hello, World!
+ 13
+ >>> printf("%d bottles of beer\n", 42)
+ 42 bottles of beer
+ 19
+ >>> printf("%f bottles of beer\n", 42.5)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ArgumentError: argument 2: exceptions.TypeError: Don't know how to convert parameter 2
+ >>>
+
+As has been mentioned before, all Python types except integers, strings, and
+unicode strings have to be wrapped in their corresponding ``ctypes`` type, so
+that they can be converted to the required C data type::
+
+ >>> printf("An int %d, a double %f\n", 1234, c_double(3.14))
+ Integer 1234, double 3.1400001049
+ 31
+ >>>
+
+
+.. _ctypes-calling-functions-with-own-custom-data-types:
+
+Calling functions with your own custom data types
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+You can also customize ``ctypes`` argument conversion to allow instances of your
+own classes be used as function arguments. ``ctypes`` looks for an
+:attr:`_as_parameter_` attribute and uses this as the function argument. Of
+course, it must be one of integer, string, or unicode::
+
+ >>> class Bottles(object):
+ ... def __init__(self, number):
+ ... self._as_parameter_ = number
+ ...
+ >>> bottles = Bottles(42)
+ >>> printf("%d bottles of beer\n", bottles)
+ 42 bottles of beer
+ 19
+ >>>
+
+If you don't want to store the instance's data in the :attr:`_as_parameter_`
+instance variable, you could define a ``property`` which makes the data
+avaiblable.
+
+
+.. _ctypes-specifying-required-argument-types:
+
+Specifying the required argument types (function prototypes)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+It is possible to specify the required argument types of functions exported from
+DLLs by setting the :attr:`argtypes` attribute.
+
+:attr:`argtypes` must be a sequence of C data types (the ``printf`` function is
+probably not a good example here, because it takes a variable number and
+different types of parameters depending on the format string, on the other hand
+this is quite handy to experiment with this feature)::
+
+ >>> printf.argtypes = [c_char_p, c_char_p, c_int, c_double]
+ >>> printf("String '%s', Int %d, Double %f\n", "Hi", 10, 2.2)
+ String 'Hi', Int 10, Double 2.200000
+ 37
+ >>>
+
+Specifying a format protects against incompatible argument types (just as a
+prototype for a C function), and tries to convert the arguments to valid types::
+
+ >>> printf("%d %d %d", 1, 2, 3)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ArgumentError: argument 2: exceptions.TypeError: wrong type
+ >>> printf("%s %d %f", "X", 2, 3)
+ X 2 3.00000012
+ 12
+ >>>
+
+If you have defined your own classes which you pass to function calls, you have
+to implement a :meth:`from_param` class method for them to be able to use them
+in the :attr:`argtypes` sequence. The :meth:`from_param` class method receives
+the Python object passed to the function call, it should do a typecheck or
+whatever is needed to make sure this object is acceptable, and then return the
+object itself, it's :attr:`_as_parameter_` attribute, or whatever you want to
+pass as the C function argument in this case. Again, the result should be an
+integer, string, unicode, a ``ctypes`` instance, or something having the
+:attr:`_as_parameter_` attribute.
+
+
+.. _ctypes-return-types:
+
+Return types
+^^^^^^^^^^^^
+
+By default functions are assumed to return the C ``int`` type. Other return
+types can be specified by setting the :attr:`restype` attribute of the function
+object.
+
+Here is a more advanced example, it uses the ``strchr`` function, which expects
+a string pointer and a char, and returns a pointer to a string::
+
+ >>> strchr = libc.strchr
+ >>> strchr("abcdef", ord("d")) # doctest: +SKIP
+ 8059983
+ >>> strchr.restype = c_char_p # c_char_p is a pointer to a string
+ >>> strchr("abcdef", ord("d"))
+ 'def'
+ >>> print strchr("abcdef", ord("x"))
+ None
+ >>>
+
+If you want to avoid the ``ord("x")`` calls above, you can set the
+:attr:`argtypes` attribute, and the second argument will be converted from a
+single character Python string into a C char::
+
+ >>> strchr.restype = c_char_p
+ >>> strchr.argtypes = [c_char_p, c_char]
+ >>> strchr("abcdef", "d")
+ 'def'
+ >>> strchr("abcdef", "def")
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ArgumentError: argument 2: exceptions.TypeError: one character string expected
+ >>> print strchr("abcdef", "x")
+ None
+ >>> strchr("abcdef", "d")
+ 'def'
+ >>>
+
+You can also use a callable Python object (a function or a class for example) as
+the :attr:`restype` attribute, if the foreign function returns an integer. The
+callable will be called with the ``integer`` the C function returns, and the
+result of this call will be used as the result of your function call. This is
+useful to check for error return values and automatically raise an exception::
+
+ >>> GetModuleHandle = windll.kernel32.GetModuleHandleA # doctest: +WINDOWS
+ >>> def ValidHandle(value):
+ ... if value == 0:
+ ... raise WinError()
+ ... return value
+ ...
+ >>>
+ >>> GetModuleHandle.restype = ValidHandle # doctest: +WINDOWS
+ >>> GetModuleHandle(None) # doctest: +WINDOWS
+ 486539264
+ >>> GetModuleHandle("something silly") # doctest: +WINDOWS
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "<stdin>", line 3, in ValidHandle
+ WindowsError: [Errno 126] The specified module could not be found.
+ >>>
+
+``WinError`` is a function which will call Windows ``FormatMessage()`` api to
+get the string representation of an error code, and *returns* an exception.
+``WinError`` takes an optional error code parameter, if no one is used, it calls
+:func:`GetLastError` to retrieve it.
+
+Please note that a much more powerful error checking mechanism is available
+through the :attr:`errcheck` attribute; see the reference manual for details.
+
+
+.. _ctypes-passing-pointers:
+
+Passing pointers (or: passing parameters by reference)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sometimes a C api function expects a *pointer* to a data type as parameter,
+probably to write into the corresponding location, or if the data is too large
+to be passed by value. This is also known as *passing parameters by reference*.
+
+``ctypes`` exports the :func:`byref` function which is used to pass parameters
+by reference. The same effect can be achieved with the ``pointer`` function,
+although ``pointer`` does a lot more work since it constructs a real pointer
+object, so it is faster to use :func:`byref` if you don't need the pointer
+object in Python itself::
+
+ >>> i = c_int()
+ >>> f = c_float()
+ >>> s = create_string_buffer('\000' * 32)
+ >>> print i.value, f.value, repr(s.value)
+ 0 0.0 ''
+ >>> libc.sscanf("1 3.14 Hello", "%d %f %s",
+ ... byref(i), byref(f), s)
+ 3
+ >>> print i.value, f.value, repr(s.value)
+ 1 3.1400001049 'Hello'
+ >>>
+
+
+.. _ctypes-structures-unions:
+
+Structures and unions
+^^^^^^^^^^^^^^^^^^^^^
+
+Structures and unions must derive from the :class:`Structure` and :class:`Union`
+base classes which are defined in the ``ctypes`` module. Each subclass must
+define a :attr:`_fields_` attribute. :attr:`_fields_` must be a list of
+*2-tuples*, containing a *field name* and a *field type*.
+
+The field type must be a ``ctypes`` type like :class:`c_int`, or any other
+derived ``ctypes`` type: structure, union, array, pointer.
+
+Here is a simple example of a POINT structure, which contains two integers named
+``x`` and ``y``, and also shows how to initialize a structure in the
+constructor::
+
+ >>> from ctypes import *
+ >>> class POINT(Structure):
+ ... _fields_ = [("x", c_int),
+ ... ("y", c_int)]
+ ...
+ >>> point = POINT(10, 20)
+ >>> print point.x, point.y
+ 10 20
+ >>> point = POINT(y=5)
+ >>> print point.x, point.y
+ 0 5
+ >>> POINT(1, 2, 3)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: too many initializers
+ >>>
+
+You can, however, build much more complicated structures. Structures can itself
+contain other structures by using a structure as a field type.
+
+Here is a RECT structure which contains two POINTs named ``upperleft`` and
+``lowerright`` ::
+
+ >>> class RECT(Structure):
+ ... _fields_ = [("upperleft", POINT),
+ ... ("lowerright", POINT)]
+ ...
+ >>> rc = RECT(point)
+ >>> print rc.upperleft.x, rc.upperleft.y
+ 0 5
+ >>> print rc.lowerright.x, rc.lowerright.y
+ 0 0
+ >>>
+
+Nested structures can also be initialized in the constructor in several ways::
+
+ >>> r = RECT(POINT(1, 2), POINT(3, 4))
+ >>> r = RECT((1, 2), (3, 4))
+
+Fields descriptors can be retrieved from the *class*, they are useful for
+debugging because they can provide useful information::
+
+ >>> print POINT.x
+ <Field type=c_long, ofs=0, size=4>
+ >>> print POINT.y
+ <Field type=c_long, ofs=4, size=4>
+ >>>
+
+
+.. _ctypes-structureunion-alignment-byte-order:
+
+Structure/union alignment and byte order
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+By default, Structure and Union fields are aligned in the same way the C
+compiler does it. It is possible to override this behaviour be specifying a
+:attr:`_pack_` class attribute in the subclass definition. This must be set to a
+positive integer and specifies the maximum alignment for the fields. This is
+what ``#pragma pack(n)`` also does in MSVC.
+
+``ctypes`` uses the native byte order for Structures and Unions. To build
+structures with non-native byte order, you can use one of the
+BigEndianStructure, LittleEndianStructure, BigEndianUnion, and LittleEndianUnion
+base classes. These classes cannot contain pointer fields.
+
+
+.. _ctypes-bit-fields-in-structures-unions:
+
+Bit fields in structures and unions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+It is possible to create structures and unions containing bit fields. Bit fields
+are only possible for integer fields, the bit width is specified as the third
+item in the :attr:`_fields_` tuples::
+
+ >>> class Int(Structure):
+ ... _fields_ = [("first_16", c_int, 16),
+ ... ("second_16", c_int, 16)]
+ ...
+ >>> print Int.first_16
+ <Field type=c_long, ofs=0:0, bits=16>
+ >>> print Int.second_16
+ <Field type=c_long, ofs=0:16, bits=16>
+ >>>
+
+
+.. _ctypes-arrays:
+
+Arrays
+^^^^^^
+
+Arrays are sequences, containing a fixed number of instances of the same type.
+
+The recommended way to create array types is by multiplying a data type with a
+positive integer::
+
+ TenPointsArrayType = POINT * 10
+
+Here is an example of an somewhat artifical data type, a structure containing 4
+POINTs among other stuff::
+
+ >>> from ctypes import *
+ >>> class POINT(Structure):
+ ... _fields_ = ("x", c_int), ("y", c_int)
+ ...
+ >>> class MyStruct(Structure):
+ ... _fields_ = [("a", c_int),
+ ... ("b", c_float),
+ ... ("point_array", POINT * 4)]
+ >>>
+ >>> print len(MyStruct().point_array)
+ 4
+ >>>
+
+Instances are created in the usual way, by calling the class::
+
+ arr = TenPointsArrayType()
+ for pt in arr:
+ print pt.x, pt.y
+
+The above code print a series of ``0 0`` lines, because the array contents is
+initialized to zeros.
+
+Initializers of the correct type can also be specified::
+
+ >>> from ctypes import *
+ >>> TenIntegers = c_int * 10
+ >>> ii = TenIntegers(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ >>> print ii
+ <c_long_Array_10 object at 0x...>
+ >>> for i in ii: print i,
+ ...
+ 1 2 3 4 5 6 7 8 9 10
+ >>>
+
+
+.. _ctypes-pointers:
+
+Pointers
+^^^^^^^^
+
+Pointer instances are created by calling the ``pointer`` function on a
+``ctypes`` type::
+
+ >>> from ctypes import *
+ >>> i = c_int(42)
+ >>> pi = pointer(i)
+ >>>
+
+Pointer instances have a ``contents`` attribute which returns the object to
+which the pointer points, the ``i`` object above::
+
+ >>> pi.contents
+ c_long(42)
+ >>>
+
+Note that ``ctypes`` does not have OOR (original object return), it constructs a
+new, equivalent object each time you retrieve an attribute::
+
+ >>> pi.contents is i
+ False
+ >>> pi.contents is pi.contents
+ False
+ >>>
+
+Assigning another :class:`c_int` instance to the pointer's contents attribute
+would cause the pointer to point to the memory location where this is stored::
+
+ >>> i = c_int(99)
+ >>> pi.contents = i
+ >>> pi.contents
+ c_long(99)
+ >>>
+
+Pointer instances can also be indexed with integers::
+
+ >>> pi[0]
+ 99
+ >>>
+
+Assigning to an integer index changes the pointed to value::
+
+ >>> print i
+ c_long(99)
+ >>> pi[0] = 22
+ >>> print i
+ c_long(22)
+ >>>
+
+It is also possible to use indexes different from 0, but you must know what
+you're doing, just as in C: You can access or change arbitrary memory locations.
+Generally you only use this feature if you receive a pointer from a C function,
+and you *know* that the pointer actually points to an array instead of a single
+item.
+
+Behind the scenes, the ``pointer`` function does more than simply create pointer
+instances, it has to create pointer *types* first. This is done with the
+``POINTER`` function, which accepts any ``ctypes`` type, and returns a new
+type::
+
+ >>> PI = POINTER(c_int)
+ >>> PI
+ <class 'ctypes.LP_c_long'>
+ >>> PI(42)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: expected c_long instead of int
+ >>> PI(c_int(42))
+ <ctypes.LP_c_long object at 0x...>
+ >>>
+
+Calling the pointer type without an argument creates a ``NULL`` pointer.
+``NULL`` pointers have a ``False`` boolean value::
+
+ >>> null_ptr = POINTER(c_int)()
+ >>> print bool(null_ptr)
+ False
+ >>>
+
+``ctypes`` checks for ``NULL`` when dereferencing pointers (but dereferencing
+non-\ ``NULL`` pointers would crash Python)::
+
+ >>> null_ptr[0]
+ Traceback (most recent call last):
+ ....
+ ValueError: NULL pointer access
+ >>>
+
+ >>> null_ptr[0] = 1234
+ Traceback (most recent call last):
+ ....
+ ValueError: NULL pointer access
+ >>>
+
+
+.. _ctypes-type-conversions:
+
+Type conversions
+^^^^^^^^^^^^^^^^
+
+Usually, ctypes does strict type checking. This means, if you have
+``POINTER(c_int)`` in the :attr:`argtypes` list of a function or as the type of
+a member field in a structure definition, only instances of exactly the same
+type are accepted. There are some exceptions to this rule, where ctypes accepts
+other objects. For example, you can pass compatible array instances instead of
+pointer types. So, for ``POINTER(c_int)``, ctypes accepts an array of c_int::
+
+ >>> class Bar(Structure):
+ ... _fields_ = [("count", c_int), ("values", POINTER(c_int))]
+ ...
+ >>> bar = Bar()
+ >>> bar.values = (c_int * 3)(1, 2, 3)
+ >>> bar.count = 3
+ >>> for i in range(bar.count):
+ ... print bar.values[i]
+ ...
+ 1
+ 2
+ 3
+ >>>
+
+To set a POINTER type field to ``NULL``, you can assign ``None``::
+
+ >>> bar.values = None
+ >>>
+
+XXX list other conversions...
+
+Sometimes you have instances of incompatible types. In ``C``, you can cast one
+type into another type. ``ctypes`` provides a ``cast`` function which can be
+used in the same way. The ``Bar`` structure defined above accepts
+``POINTER(c_int)`` pointers or :class:`c_int` arrays for its ``values`` field,
+but not instances of other types::
+
+ >>> bar.values = (c_byte * 4)()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: incompatible types, c_byte_Array_4 instance instead of LP_c_long instance
+ >>>
+
+For these cases, the ``cast`` function is handy.
+
+The ``cast`` function can be used to cast a ctypes instance into a pointer to a
+different ctypes data type. ``cast`` takes two parameters, a ctypes object that
+is or can be converted to a pointer of some kind, and a ctypes pointer type. It
+returns an instance of the second argument, which references the same memory
+block as the first argument::
+
+ >>> a = (c_byte * 4)()
+ >>> cast(a, POINTER(c_int))
+ <ctypes.LP_c_long object at ...>
+ >>>
+
+So, ``cast`` can be used to assign to the ``values`` field of ``Bar`` the
+structure::
+
+ >>> bar = Bar()
+ >>> bar.values = cast((c_byte * 4)(), POINTER(c_int))
+ >>> print bar.values[0]
+ 0
+ >>>
+
+
+.. _ctypes-incomplete-types:
+
+Incomplete Types
+^^^^^^^^^^^^^^^^
+
+*Incomplete Types* are structures, unions or arrays whose members are not yet
+specified. In C, they are specified by forward declarations, which are defined
+later::
+
+ struct cell; /* forward declaration */
+
+ struct {
+ char *name;
+ struct cell *next;
+ } cell;
+
+The straightforward translation into ctypes code would be this, but it does not
+work::
+
+ >>> class cell(Structure):
+ ... _fields_ = [("name", c_char_p),
+ ... ("next", POINTER(cell))]
+ ...
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "<stdin>", line 2, in cell
+ NameError: name 'cell' is not defined
+ >>>
+
+because the new ``class cell`` is not available in the class statement itself.
+In ``ctypes``, we can define the ``cell`` class and set the :attr:`_fields_`
+attribute later, after the class statement::
+
+ >>> from ctypes import *
+ >>> class cell(Structure):
+ ... pass
+ ...
+ >>> cell._fields_ = [("name", c_char_p),
+ ... ("next", POINTER(cell))]
+ >>>
+
+Lets try it. We create two instances of ``cell``, and let them point to each
+other, and finally follow the pointer chain a few times::
+
+ >>> c1 = cell()
+ >>> c1.name = "foo"
+ >>> c2 = cell()
+ >>> c2.name = "bar"
+ >>> c1.next = pointer(c2)
+ >>> c2.next = pointer(c1)
+ >>> p = c1
+ >>> for i in range(8):
+ ... print p.name,
+ ... p = p.next[0]
+ ...
+ foo bar foo bar foo bar foo bar
+ >>>
+
+
+.. _ctypes-callback-functions:
+
+Callback functions
+^^^^^^^^^^^^^^^^^^
+
+``ctypes`` allows to create C callable function pointers from Python callables.
+These are sometimes called *callback functions*.
+
+First, you must create a class for the callback function, the class knows the
+calling convention, the return type, and the number and types of arguments this
+function will receive.
+
+The CFUNCTYPE factory function creates types for callback functions using the
+normal cdecl calling convention, and, on Windows, the WINFUNCTYPE factory
+function creates types for callback functions using the stdcall calling
+convention.
+
+Both of these factory functions are called with the result type as first
+argument, and the callback functions expected argument types as the remaining
+arguments.
+
+I will present an example here which uses the standard C library's :func:`qsort`
+function, this is used to sort items with the help of a callback function.
+:func:`qsort` will be used to sort an array of integers::
+
+ >>> IntArray5 = c_int * 5
+ >>> ia = IntArray5(5, 1, 7, 33, 99)
+ >>> qsort = libc.qsort
+ >>> qsort.restype = None
+ >>>
+
+:func:`qsort` must be called with a pointer to the data to sort, the number of
+items in the data array, the size of one item, and a pointer to the comparison
+function, the callback. The callback will then be called with two pointers to
+items, and it must return a negative integer if the first item is smaller than
+the second, a zero if they are equal, and a positive integer else.
+
+So our callback function receives pointers to integers, and must return an
+integer. First we create the ``type`` for the callback function::
+
+ >>> CMPFUNC = CFUNCTYPE(c_int, POINTER(c_int), POINTER(c_int))
+ >>>
+
+For the first implementation of the callback function, we simply print the
+arguments we get, and return 0 (incremental development ;-)::
+
+ >>> def py_cmp_func(a, b):
+ ... print "py_cmp_func", a, b
+ ... return 0
+ ...
+ >>>
+
+Create the C callable callback::
+
+ >>> cmp_func = CMPFUNC(py_cmp_func)
+ >>>
+
+And we're ready to go::
+
+ >>> qsort(ia, len(ia), sizeof(c_int), cmp_func) # doctest: +WINDOWS
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ py_cmp_func <ctypes.LP_c_long object at 0x00...> <ctypes.LP_c_long object at 0x00...>
+ >>>
+
+We know how to access the contents of a pointer, so lets redefine our callback::
+
+ >>> def py_cmp_func(a, b):
+ ... print "py_cmp_func", a[0], b[0]
+ ... return 0
+ ...
+ >>> cmp_func = CMPFUNC(py_cmp_func)
+ >>>
+
+Here is what we get on Windows::
+
+ >>> qsort(ia, len(ia), sizeof(c_int), cmp_func) # doctest: +WINDOWS
+ py_cmp_func 7 1
+ py_cmp_func 33 1
+ py_cmp_func 99 1
+ py_cmp_func 5 1
+ py_cmp_func 7 5
+ py_cmp_func 33 5
+ py_cmp_func 99 5
+ py_cmp_func 7 99
+ py_cmp_func 33 99
+ py_cmp_func 7 33
+ >>>
+
+It is funny to see that on linux the sort function seems to work much more
+efficient, it is doing less comparisons::
+
+ >>> qsort(ia, len(ia), sizeof(c_int), cmp_func) # doctest: +LINUX
+ py_cmp_func 5 1
+ py_cmp_func 33 99
+ py_cmp_func 7 33
+ py_cmp_func 5 7
+ py_cmp_func 1 7
+ >>>
+
+Ah, we're nearly done! The last step is to actually compare the two items and
+return a useful result::
+
+ >>> def py_cmp_func(a, b):
+ ... print "py_cmp_func", a[0], b[0]
+ ... return a[0] - b[0]
+ ...
+ >>>
+
+Final run on Windows::
+
+ >>> qsort(ia, len(ia), sizeof(c_int), CMPFUNC(py_cmp_func)) # doctest: +WINDOWS
+ py_cmp_func 33 7
+ py_cmp_func 99 33
+ py_cmp_func 5 99
+ py_cmp_func 1 99
+ py_cmp_func 33 7
+ py_cmp_func 1 33
+ py_cmp_func 5 33
+ py_cmp_func 5 7
+ py_cmp_func 1 7
+ py_cmp_func 5 1
+ >>>
+
+and on Linux::
+
+ >>> qsort(ia, len(ia), sizeof(c_int), CMPFUNC(py_cmp_func)) # doctest: +LINUX
+ py_cmp_func 5 1
+ py_cmp_func 33 99
+ py_cmp_func 7 33
+ py_cmp_func 1 7
+ py_cmp_func 5 7
+ >>>
+
+It is quite interesting to see that the Windows :func:`qsort` function needs
+more comparisons than the linux version!
+
+As we can easily check, our array is sorted now::
+
+ >>> for i in ia: print i,
+ ...
+ 1 5 7 33 99
+ >>>
+
+**Important note for callback functions:**
+
+Make sure you keep references to CFUNCTYPE objects as long as they are used from
+C code. ``ctypes`` doesn't, and if you don't, they may be garbage collected,
+crashing your program when a callback is made.
+
+
+.. _ctypes-accessing-values-exported-from-dlls:
+
+Accessing values exported from dlls
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sometimes, a dll not only exports functions, it also exports variables. An
+example in the Python library itself is the ``Py_OptimizeFlag``, an integer set
+to 0, 1, or 2, depending on the :option:`-O` or :option:`-OO` flag given on
+startup.
+
+``ctypes`` can access values like this with the :meth:`in_dll` class methods of
+the type. *pythonapi* is a predefined symbol giving access to the Python C
+api::
+
+ >>> opt_flag = c_int.in_dll(pythonapi, "Py_OptimizeFlag")
+ >>> print opt_flag
+ c_long(0)
+ >>>
+
+If the interpreter would have been started with :option:`-O`, the sample would
+have printed ``c_long(1)``, or ``c_long(2)`` if :option:`-OO` would have been
+specified.
+
+An extended example which also demonstrates the use of pointers accesses the
+``PyImport_FrozenModules`` pointer exported by Python.
+
+Quoting the Python docs: *This pointer is initialized to point to an array of
+"struct _frozen" records, terminated by one whose members are all NULL or zero.
+When a frozen module is imported, it is searched in this table. Third-party code
+could play tricks with this to provide a dynamically created collection of
+frozen modules.*
+
+So manipulating this pointer could even prove useful. To restrict the example
+size, we show only how this table can be read with ``ctypes``::
+
+ >>> from ctypes import *
+ >>>
+ >>> class struct_frozen(Structure):
+ ... _fields_ = [("name", c_char_p),
+ ... ("code", POINTER(c_ubyte)),
+ ... ("size", c_int)]
+ ...
+ >>>
+
+We have defined the ``struct _frozen`` data type, so we can get the pointer to
+the table::
+
+ >>> FrozenTable = POINTER(struct_frozen)
+ >>> table = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
+ >>>
+
+Since ``table`` is a ``pointer`` to the array of ``struct_frozen`` records, we
+can iterate over it, but we just have to make sure that our loop terminates,
+because pointers have no size. Sooner or later it would probably crash with an
+access violation or whatever, so it's better to break out of the loop when we
+hit the NULL entry::
+
+ >>> for item in table:
+ ... print item.name, item.size
+ ... if item.name is None:
+ ... break
+ ...
+ __hello__ 104
+ __phello__ -104
+ __phello__.spam 104
+ None 0
+ >>>
+
+The fact that standard Python has a frozen module and a frozen package
+(indicated by the negative size member) is not wellknown, it is only used for
+testing. Try it out with ``import __hello__`` for example.
+
+
+.. _ctypes-surprises:
+
+Surprises
+^^^^^^^^^
+
+There are some edges in ``ctypes`` where you may be expect something else than
+what actually happens.
+
+Consider the following example::
+
+ >>> from ctypes import *
+ >>> class POINT(Structure):
+ ... _fields_ = ("x", c_int), ("y", c_int)
+ ...
+ >>> class RECT(Structure):
+ ... _fields_ = ("a", POINT), ("b", POINT)
+ ...
+ >>> p1 = POINT(1, 2)
+ >>> p2 = POINT(3, 4)
+ >>> rc = RECT(p1, p2)
+ >>> print rc.a.x, rc.a.y, rc.b.x, rc.b.y
+ 1 2 3 4
+ >>> # now swap the two points
+ >>> rc.a, rc.b = rc.b, rc.a
+ >>> print rc.a.x, rc.a.y, rc.b.x, rc.b.y
+ 3 4 3 4
+ >>>
+
+Hm. We certainly expected the last statement to print ``3 4 1 2``. What
+happended? Here are the steps of the ``rc.a, rc.b = rc.b, rc.a`` line above::
+
+ >>> temp0, temp1 = rc.b, rc.a
+ >>> rc.a = temp0
+ >>> rc.b = temp1
+ >>>
+
+Note that ``temp0`` and ``temp1`` are objects still using the internal buffer of
+the ``rc`` object above. So executing ``rc.a = temp0`` copies the buffer
+contents of ``temp0`` into ``rc`` 's buffer. This, in turn, changes the
+contents of ``temp1``. So, the last assignment ``rc.b = temp1``, doesn't have
+the expected effect.
+
+Keep in mind that retrieving subobjects from Structure, Unions, and Arrays
+doesn't *copy* the subobject, instead it retrieves a wrapper object accessing
+the root-object's underlying buffer.
+
+Another example that may behave different from what one would expect is this::
+
+ >>> s = c_char_p()
+ >>> s.value = "abc def ghi"
+ >>> s.value
+ 'abc def ghi'
+ >>> s.value is s.value
+ False
+ >>>
+
+Why is it printing ``False``? ctypes instances are objects containing a memory
+block plus some descriptors accessing the contents of the memory. Storing a
+Python object in the memory block does not store the object itself, instead the
+``contents`` of the object is stored. Accessing the contents again constructs a
+new Python each time!
+
+
+.. _ctypes-variable-sized-data-types:
+
+Variable-sized data types
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+``ctypes`` provides some support for variable-sized arrays and structures (this
+was added in version 0.9.9.7).
+
+The ``resize`` function can be used to resize the memory buffer of an existing
+ctypes object. The function takes the object as first argument, and the
+requested size in bytes as the second argument. The memory block cannot be made
+smaller than the natural memory block specified by the objects type, a
+``ValueError`` is raised if this is tried::
+
+ >>> short_array = (c_short * 4)()
+ >>> print sizeof(short_array)
+ 8
+ >>> resize(short_array, 4)
+ Traceback (most recent call last):
+ ...
+ ValueError: minimum size is 8
+ >>> resize(short_array, 32)
+ >>> sizeof(short_array)
+ 32
+ >>> sizeof(type(short_array))
+ 8
+ >>>
+
+This is nice and fine, but how would one access the additional elements
+contained in this array? Since the type still only knows about 4 elements, we
+get errors accessing other elements::
+
+ >>> short_array[:]
+ [0, 0, 0, 0]
+ >>> short_array[7]
+ Traceback (most recent call last):
+ ...
+ IndexError: invalid index
+ >>>
+
+Another way to use variable-sized data types with ``ctypes`` is to use the
+dynamic nature of Python, and (re-)define the data type after the required size
+is already known, on a case by case basis.
+
+
+.. _ctypes-bugs-todo-non-implemented-things:
+
+Bugs, ToDo and non-implemented things
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Enumeration types are not implemented. You can do it easily yourself, using
+:class:`c_int` as the base class.
+
+``long double`` is not implemented.
+
+.. % Local Variables:
+.. % compile-command: "make.bat"
+.. % End:
+
+
+.. _ctypes-ctypes-reference:
+
+ctypes reference
+----------------
+
+
+.. _ctypes-finding-shared-libraries:
+
+Finding shared libraries
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+When programming in a compiled language, shared libraries are accessed when
+compiling/linking a program, and when the program is run.
+
+The purpose of the ``find_library`` function is to locate a library in a way
+similar to what the compiler does (on platforms with several versions of a
+shared library the most recent should be loaded), while the ctypes library
+loaders act like when a program is run, and call the runtime loader directly.
+
+The ``ctypes.util`` module provides a function which can help to determine the
+library to load.
+
+
+.. data:: find_library(name)
+ :noindex:
+
+ Try to find a library and return a pathname. *name* is the library name without
+ any prefix like *lib*, suffix like ``.so``, ``.dylib`` or version number (this
+ is the form used for the posix linker option :option:`-l`). If no library can
+ be found, returns ``None``.
+
+The exact functionality is system dependend.
+
+On Linux, ``find_library`` tries to run external programs (/sbin/ldconfig, gcc,
+and objdump) to find the library file. It returns the filename of the library
+file. Here are sone examples::
+
+ >>> from ctypes.util import find_library
+ >>> find_library("m")
+ 'libm.so.6'
+ >>> find_library("c")
+ 'libc.so.6'
+ >>> find_library("bz2")
+ 'libbz2.so.1.0'
+ >>>
+
+On OS X, ``find_library`` tries several predefined naming schemes and paths to
+locate the library, and returns a full pathname if successfull::
+
+ >>> from ctypes.util import find_library
+ >>> find_library("c")
+ '/usr/lib/libc.dylib'
+ >>> find_library("m")
+ '/usr/lib/libm.dylib'
+ >>> find_library("bz2")
+ '/usr/lib/libbz2.dylib'
+ >>> find_library("AGL")
+ '/System/Library/Frameworks/AGL.framework/AGL'
+ >>>
+
+On Windows, ``find_library`` searches along the system search path, and returns
+the full pathname, but since there is no predefined naming scheme a call like
+``find_library("c")`` will fail and return ``None``.
+
+If wrapping a shared library with ``ctypes``, it *may* be better to determine
+the shared library name at development type, and hardcode that into the wrapper
+module instead of using ``find_library`` to locate the library at runtime.
+
+
+.. _ctypes-loading-shared-libraries:
+
+Loading shared libraries
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+There are several ways to loaded shared libraries into the Python process. One
+way is to instantiate one of the following classes:
+
+
+.. class:: CDLL(name, mode=DEFAULT_MODE, handle=None)
+
+ Instances of this class represent loaded shared libraries. Functions in these
+ libraries use the standard C calling convention, and are assumed to return
+ ``int``.
+
+
+.. class:: OleDLL(name, mode=DEFAULT_MODE, handle=None)
+
+ Windows only: Instances of this class represent loaded shared libraries,
+ functions in these libraries use the ``stdcall`` calling convention, and are
+ assumed to return the windows specific :class:`HRESULT` code. :class:`HRESULT`
+ values contain information specifying whether the function call failed or
+ succeeded, together with additional error code. If the return value signals a
+ failure, an :class:`WindowsError` is automatically raised.
+
+
+.. class:: WinDLL(name, mode=DEFAULT_MODE, handle=None)
+
+ Windows only: Instances of this class represent loaded shared libraries,
+ functions in these libraries use the ``stdcall`` calling convention, and are
+ assumed to return ``int`` by default.
+
+ On Windows CE only the standard calling convention is used, for convenience the
+ :class:`WinDLL` and :class:`OleDLL` use the standard calling convention on this
+ platform.
+
+The Python GIL is released before calling any function exported by these
+libraries, and reaquired afterwards.
+
+
+.. class:: PyDLL(name, mode=DEFAULT_MODE, handle=None)
+
+ Instances of this class behave like :class:`CDLL` instances, except that the
+ Python GIL is *not* released during the function call, and after the function
+ execution the Python error flag is checked. If the error flag is set, a Python
+ exception is raised.
+
+ Thus, this is only useful to call Python C api functions directly.
+
+All these classes can be instantiated by calling them with at least one
+argument, the pathname of the shared library. If you have an existing handle to
+an already loaded shard library, it can be passed as the ``handle`` named
+parameter, otherwise the underlying platforms ``dlopen`` or :meth:`LoadLibrary`
+function is used to load the library into the process, and to get a handle to
+it.
+
+The *mode* parameter can be used to specify how the library is loaded. For
+details, consult the ``dlopen(3)`` manpage, on Windows, *mode* is ignored.
+
+
+.. data:: RTLD_GLOBAL
+ :noindex:
+
+ Flag to use as *mode* parameter. On platforms where this flag is not available,
+ it is defined as the integer zero.
+
+
+.. data:: RTLD_LOCAL
+ :noindex:
+
+ Flag to use as *mode* parameter. On platforms where this is not available, it
+ is the same as *RTLD_GLOBAL*.
+
+
+.. data:: DEFAULT_MODE
+ :noindex:
+
+ The default mode which is used to load shared libraries. On OSX 10.3, this is
+ *RTLD_GLOBAL*, otherwise it is the same as *RTLD_LOCAL*.
+
+Instances of these classes have no public methods, however :meth:`__getattr__`
+and :meth:`__getitem__` have special behaviour: functions exported by the shared
+library can be accessed as attributes of by index. Please note that both
+:meth:`__getattr__` and :meth:`__getitem__` cache their result, so calling them
+repeatedly returns the same object each time.
+
+The following public attributes are available, their name starts with an
+underscore to not clash with exported function names:
+
+
+.. attribute:: PyDLL._handle
+
+ The system handle used to access the library.
+
+
+.. attribute:: PyDLL._name
+
+ The name of the library passed in the contructor.
+
+Shared libraries can also be loaded by using one of the prefabricated objects,
+which are instances of the :class:`LibraryLoader` class, either by calling the
+:meth:`LoadLibrary` method, or by retrieving the library as attribute of the
+loader instance.
+
+
+.. class:: LibraryLoader(dlltype)
+
+ Class which loads shared libraries. ``dlltype`` should be one of the
+ :class:`CDLL`, :class:`PyDLL`, :class:`WinDLL`, or :class:`OleDLL` types.
+
+ :meth:`__getattr__` has special behaviour: It allows to load a shared library by
+ accessing it as attribute of a library loader instance. The result is cached,
+ so repeated attribute accesses return the same library each time.
+
+
+.. method:: LibraryLoader.LoadLibrary(name)
+
+ Load a shared library into the process and return it. This method always
+ returns a new instance of the library.
+
+These prefabricated library loaders are available:
+
+
+.. data:: cdll
+ :noindex:
+
+ Creates :class:`CDLL` instances.
+
+
+.. data:: windll
+ :noindex:
+
+ Windows only: Creates :class:`WinDLL` instances.
+
+
+.. data:: oledll
+ :noindex:
+
+ Windows only: Creates :class:`OleDLL` instances.
+
+
+.. data:: pydll
+ :noindex:
+
+ Creates :class:`PyDLL` instances.
+
+For accessing the C Python api directly, a ready-to-use Python shared library
+object is available:
+
+
+.. data:: pythonapi
+ :noindex:
+
+ An instance of :class:`PyDLL` that exposes Python C api functions as attributes.
+ Note that all these functions are assumed to return C ``int``, which is of
+ course not always the truth, so you have to assign the correct :attr:`restype`
+ attribute to use these functions.
+
+
+.. _ctypes-foreign-functions:
+
+Foreign functions
+^^^^^^^^^^^^^^^^^
+
+As explained in the previous section, foreign functions can be accessed as
+attributes of loaded shared libraries. The function objects created in this way
+by default accept any number of arguments, accept any ctypes data instances as
+arguments, and return the default result type specified by the library loader.
+They are instances of a private class:
+
+
+.. class:: _FuncPtr
+
+ Base class for C callable foreign functions.
+
+Instances of foreign functions are also C compatible data types; they represent
+C function pointers.
+
+This behaviour can be customized by assigning to special attributes of the
+foreign function object.
+
+
+.. attribute:: _FuncPtr.restype
+
+ Assign a ctypes type to specify the result type of the foreign function. Use
+ ``None`` for ``void`` a function not returning anything.
+
+ It is possible to assign a callable Python object that is not a ctypes type, in
+ this case the function is assumed to return a C ``int``, and the callable will
+ be called with this integer, allowing to do further processing or error
+ checking. Using this is deprecated, for more flexible postprocessing or error
+ checking use a ctypes data type as :attr:`restype` and assign a callable to the
+ :attr:`errcheck` attribute.
+
+
+.. attribute:: _FuncPtr.argtypes
+
+ Assign a tuple of ctypes types to specify the argument types that the function
+ accepts. Functions using the ``stdcall`` calling convention can only be called
+ with the same number of arguments as the length of this tuple; functions using
+ the C calling convention accept additional, unspecified arguments as well.
+
+ When a foreign function is called, each actual argument is passed to the
+ :meth:`from_param` class method of the items in the :attr:`argtypes` tuple, this
+ method allows to adapt the actual argument to an object that the foreign
+ function accepts. For example, a :class:`c_char_p` item in the :attr:`argtypes`
+ tuple will convert a unicode string passed as argument into an byte string using
+ ctypes conversion rules.
+
+ New: It is now possible to put items in argtypes which are not ctypes types, but
+ each item must have a :meth:`from_param` method which returns a value usable as
+ argument (integer, string, ctypes instance). This allows to define adapters
+ that can adapt custom objects as function parameters.
+
+
+.. attribute:: _FuncPtr.errcheck
+
+ Assign a Python function or another callable to this attribute. The callable
+ will be called with three or more arguments:
+
+
+.. function:: callable(result, func, arguments)
+ :noindex:
+
+ ``result`` is what the foreign function returns, as specified by the
+ :attr:`restype` attribute.
+
+ ``func`` is the foreign function object itself, this allows to reuse the same
+ callable object to check or postprocess the results of several functions.
+
+ ``arguments`` is a tuple containing the parameters originally passed to the
+ function call, this allows to specialize the behaviour on the arguments used.
+
+ The object that this function returns will be returned from the foreign function
+ call, but it can also check the result value and raise an exception if the
+ foreign function call failed.
+
+
+.. exception:: ArgumentError()
+
+ This exception is raised when a foreign function call cannot convert one of the
+ passed arguments.
+
+
+.. _ctypes-function-prototypes:
+
+Function prototypes
+^^^^^^^^^^^^^^^^^^^
+
+Foreign functions can also be created by instantiating function prototypes.
+Function prototypes are similar to function prototypes in C; they describe a
+function (return type, argument types, calling convention) without defining an
+implementation. The factory functions must be called with the desired result
+type and the argument types of the function.
+
+
+.. function:: CFUNCTYPE(restype, *argtypes)
+
+ The returned function prototype creates functions that use the standard C
+ calling convention. The function will release the GIL during the call.
+
+
+.. function:: WINFUNCTYPE(restype, *argtypes)
+
+ Windows only: The returned function prototype creates functions that use the
+ ``stdcall`` calling convention, except on Windows CE where :func:`WINFUNCTYPE`
+ is the same as :func:`CFUNCTYPE`. The function will release the GIL during the
+ call.
+
+
+.. function:: PYFUNCTYPE(restype, *argtypes)
+
+ The returned function prototype creates functions that use the Python calling
+ convention. The function will *not* release the GIL during the call.
+
+Function prototypes created by the factory functions can be instantiated in
+different ways, depending on the type and number of the parameters in the call.
+
+
+.. function:: prototype(address)
+ :noindex:
+
+ Returns a foreign function at the specified address.
+
+
+.. function:: prototype(callable)
+ :noindex:
+
+ Create a C callable function (a callback function) from a Python ``callable``.
+
+
+.. function:: prototype(func_spec[, paramflags])
+ :noindex:
+
+ Returns a foreign function exported by a shared library. ``func_spec`` must be a
+ 2-tuple ``(name_or_ordinal, library)``. The first item is the name of the
+ exported function as string, or the ordinal of the exported function as small
+ integer. The second item is the shared library instance.
+
+
+.. function:: prototype(vtbl_index, name[, paramflags[, iid]])
+ :noindex:
+
+ Returns a foreign function that will call a COM method. ``vtbl_index`` is the
+ index into the virtual function table, a small nonnegative integer. *name* is
+ name of the COM method. *iid* is an optional pointer to the interface identifier
+ which is used in extended error reporting.
+
+ COM methods use a special calling convention: They require a pointer to the COM
+ interface as first argument, in addition to those parameters that are specified
+ in the :attr:`argtypes` tuple.
+
+The optional *paramflags* parameter creates foreign function wrappers with much
+more functionality than the features described above.
+
+*paramflags* must be a tuple of the same length as :attr:`argtypes`.
+
+Each item in this tuple contains further information about a parameter, it must
+be a tuple containing 1, 2, or 3 items.
+
+The first item is an integer containing flags for the parameter:
+
+
+.. data:: 1
+ :noindex:
+
+ Specifies an input parameter to the function.
+
+
+.. data:: 2
+ :noindex:
+
+ Output parameter. The foreign function fills in a value.
+
+
+.. data:: 4
+ :noindex:
+
+ Input parameter which defaults to the integer zero.
+
+The optional second item is the parameter name as string. If this is specified,
+the foreign function can be called with named parameters.
+
+The optional third item is the default value for this parameter.
+
+This example demonstrates how to wrap the Windows ``MessageBoxA`` function so
+that it supports default parameters and named arguments. The C declaration from
+the windows header file is this::
+
+ WINUSERAPI int WINAPI
+ MessageBoxA(
+ HWND hWnd ,
+ LPCSTR lpText,
+ LPCSTR lpCaption,
+ UINT uType);
+
+Here is the wrapping with ``ctypes``:
+
+ ::
+
+ >>> from ctypes import c_int, WINFUNCTYPE, windll
+ >>> from ctypes.wintypes import HWND, LPCSTR, UINT
+ >>> prototype = WINFUNCTYPE(c_int, HWND, LPCSTR, LPCSTR, UINT)
+ >>> paramflags = (1, "hwnd", 0), (1, "text", "Hi"), (1, "caption", None), (1, "flags", 0)
+ >>> MessageBox = prototype(("MessageBoxA", windll.user32), paramflags)
+ >>>
+
+The MessageBox foreign function can now be called in these ways::
+
+ >>> MessageBox()
+ >>> MessageBox(text="Spam, spam, spam")
+ >>> MessageBox(flags=2, text="foo bar")
+ >>>
+
+A second example demonstrates output parameters. The win32 ``GetWindowRect``
+function retrieves the dimensions of a specified window by copying them into
+``RECT`` structure that the caller has to supply. Here is the C declaration::
+
+ WINUSERAPI BOOL WINAPI
+ GetWindowRect(
+ HWND hWnd,
+ LPRECT lpRect);
+
+Here is the wrapping with ``ctypes``:
+
+ ::
+
+ >>> from ctypes import POINTER, WINFUNCTYPE, windll, WinError
+ >>> from ctypes.wintypes import BOOL, HWND, RECT
+ >>> prototype = WINFUNCTYPE(BOOL, HWND, POINTER(RECT))
+ >>> paramflags = (1, "hwnd"), (2, "lprect")
+ >>> GetWindowRect = prototype(("GetWindowRect", windll.user32), paramflags)
+ >>>
+
+Functions with output parameters will automatically return the output parameter
+value if there is a single one, or a tuple containing the output parameter
+values when there are more than one, so the GetWindowRect function now returns a
+RECT instance, when called.
+
+Output parameters can be combined with the :attr:`errcheck` protocol to do
+further output processing and error checking. The win32 ``GetWindowRect`` api
+function returns a ``BOOL`` to signal success or failure, so this function could
+do the error checking, and raises an exception when the api call failed::
+
+ >>> def errcheck(result, func, args):
+ ... if not result:
+ ... raise WinError()
+ ... return args
+ >>> GetWindowRect.errcheck = errcheck
+ >>>
+
+If the :attr:`errcheck` function returns the argument tuple it receives
+unchanged, ``ctypes`` continues the normal processing it does on the output
+parameters. If you want to return a tuple of window coordinates instead of a
+``RECT`` instance, you can retrieve the fields in the function and return them
+instead, the normal processing will no longer take place::
+
+ >>> def errcheck(result, func, args):
+ ... if not result:
+ ... raise WinError()
+ ... rc = args[1]
+ ... return rc.left, rc.top, rc.bottom, rc.right
+ >>>
+ >>> GetWindowRect.errcheck = errcheck
+ >>>
+
+
+.. _ctypes-utility-functions:
+
+Utility functions
+^^^^^^^^^^^^^^^^^
+
+
+.. function:: addressof(obj)
+
+ Returns the address of the memory buffer as integer. ``obj`` must be an
+ instance of a ctypes type.
+
+
+.. function:: alignment(obj_or_type)
+
+ Returns the alignment requirements of a ctypes type. ``obj_or_type`` must be a
+ ctypes type or instance.
+
+
+.. function:: byref(obj)
+
+ Returns a light-weight pointer to ``obj``, which must be an instance of a ctypes
+ type. The returned object can only be used as a foreign function call parameter.
+ It behaves similar to ``pointer(obj)``, but the construction is a lot faster.
+
+
+.. function:: cast(obj, type)
+
+ This function is similar to the cast operator in C. It returns a new instance of
+ ``type`` which points to the same memory block as ``obj``. ``type`` must be a
+ pointer type, and ``obj`` must be an object that can be interpreted as a
+ pointer.
+
+
+.. function:: create_string_buffer(init_or_size[, size])
+
+ This function creates a mutable character buffer. The returned object is a
+ ctypes array of :class:`c_char`.
+
+ ``init_or_size`` must be an integer which specifies the size of the array, or a
+ string which will be used to initialize the array items.
+
+ If a string is specified as first argument, the buffer is made one item larger
+ than the length of the string so that the last element in the array is a NUL
+ termination character. An integer can be passed as second argument which allows
+ to specify the size of the array if the length of the string should not be used.
+
+ If the first parameter is a unicode string, it is converted into an 8-bit string
+ according to ctypes conversion rules.
+
+
+.. function:: create_unicode_buffer(init_or_size[, size])
+
+ This function creates a mutable unicode character buffer. The returned object is
+ a ctypes array of :class:`c_wchar`.
+
+ ``init_or_size`` must be an integer which specifies the size of the array, or a
+ unicode string which will be used to initialize the array items.
+
+ If a unicode string is specified as first argument, the buffer is made one item
+ larger than the length of the string so that the last element in the array is a
+ NUL termination character. An integer can be passed as second argument which
+ allows to specify the size of the array if the length of the string should not
+ be used.
+
+ If the first parameter is a 8-bit string, it is converted into an unicode string
+ according to ctypes conversion rules.
+
+
+.. function:: DllCanUnloadNow()
+
+ Windows only: This function is a hook which allows to implement inprocess COM
+ servers with ctypes. It is called from the DllCanUnloadNow function that the
+ _ctypes extension dll exports.
+
+
+.. function:: DllGetClassObject()
+
+ Windows only: This function is a hook which allows to implement inprocess COM
+ servers with ctypes. It is called from the DllGetClassObject function that the
+ ``_ctypes`` extension dll exports.
+
+
+.. function:: FormatError([code])
+
+ Windows only: Returns a textual description of the error code. If no error code
+ is specified, the last error code is used by calling the Windows api function
+ GetLastError.
+
+
+.. function:: GetLastError()
+
+ Windows only: Returns the last error code set by Windows in the calling thread.
+
+
+.. function:: memmove(dst, src, count)
+
+ Same as the standard C memmove library function: copies *count* bytes from
+ ``src`` to *dst*. *dst* and ``src`` must be integers or ctypes instances that
+ can be converted to pointers.
+
+
+.. function:: memset(dst, c, count)
+
+ Same as the standard C memset library function: fills the memory block at
+ address *dst* with *count* bytes of value *c*. *dst* must be an integer
+ specifying an address, or a ctypes instance.
+
+
+.. function:: POINTER(type)
+
+ This factory function creates and returns a new ctypes pointer type. Pointer
+ types are cached an reused internally, so calling this function repeatedly is
+ cheap. type must be a ctypes type.
+
+
+.. function:: pointer(obj)
+
+ This function creates a new pointer instance, pointing to ``obj``. The returned
+ object is of the type POINTER(type(obj)).
+
+ Note: If you just want to pass a pointer to an object to a foreign function
+ call, you should use ``byref(obj)`` which is much faster.
+
+
+.. function:: resize(obj, size)
+
+ This function resizes the internal memory buffer of obj, which must be an
+ instance of a ctypes type. It is not possible to make the buffer smaller than
+ the native size of the objects type, as given by sizeof(type(obj)), but it is
+ possible to enlarge the buffer.
+
+
+.. function:: set_conversion_mode(encoding, errors)
+
+ This function sets the rules that ctypes objects use when converting between
+ 8-bit strings and unicode strings. encoding must be a string specifying an
+ encoding, like ``'utf-8'`` or ``'mbcs'``, errors must be a string specifying the
+ error handling on encoding/decoding errors. Examples of possible values are
+ ``"strict"``, ``"replace"``, or ``"ignore"``.
+
+ ``set_conversion_mode`` returns a 2-tuple containing the previous conversion
+ rules. On windows, the initial conversion rules are ``('mbcs', 'ignore')``, on
+ other systems ``('ascii', 'strict')``.
+
+
+.. function:: sizeof(obj_or_type)
+
+ Returns the size in bytes of a ctypes type or instance memory buffer. Does the
+ same as the C ``sizeof()`` function.
+
+
+.. function:: string_at(address[, size])
+
+ This function returns the string starting at memory address address. If size
+ is specified, it is used as size, otherwise the string is assumed to be
+ zero-terminated.
+
+
+.. function:: WinError(code=None, descr=None)
+
+ Windows only: this function is probably the worst-named thing in ctypes. It
+ creates an instance of WindowsError. If *code* is not specified,
+ ``GetLastError`` is called to determine the error code. If ``descr`` is not
+ spcified, :func:`FormatError` is called to get a textual description of the
+ error.
+
+
+.. function:: wstring_at(address)
+
+ This function returns the wide character string starting at memory address
+ ``address`` as unicode string. If ``size`` is specified, it is used as the
+ number of characters of the string, otherwise the string is assumed to be
+ zero-terminated.
+
+
+.. _ctypes-data-types:
+
+Data types
+^^^^^^^^^^
+
+
+.. class:: _CData
+
+ This non-public class is the common base class of all ctypes data types. Among
+ other things, all ctypes type instances contain a memory block that hold C
+ compatible data; the address of the memory block is returned by the
+ ``addressof()`` helper function. Another instance variable is exposed as
+ :attr:`_objects`; this contains other Python objects that need to be kept alive
+ in case the memory block contains pointers.
+
+Common methods of ctypes data types, these are all class methods (to be exact,
+they are methods of the metaclass):
+
+
+.. method:: _CData.from_address(address)
+
+ This method returns a ctypes type instance using the memory specified by address
+ which must be an integer.
+
+
+.. method:: _CData.from_param(obj)
+
+ This method adapts obj to a ctypes type. It is called with the actual object
+ used in a foreign function call, when the type is present in the foreign
+ functions :attr:`argtypes` tuple; it must return an object that can be used as
+ function call parameter.
+
+ All ctypes data types have a default implementation of this classmethod,
+ normally it returns ``obj`` if that is an instance of the type. Some types
+ accept other objects as well.
+
+
+.. method:: _CData.in_dll(library, name)
+
+ This method returns a ctypes type instance exported by a shared library. *name*
+ is the name of the symbol that exports the data, *library* is the loaded shared
+ library.
+
+Common instance variables of ctypes data types:
+
+
+.. attribute:: _CData._b_base_
+
+ Sometimes ctypes data instances do not own the memory block they contain,
+ instead they share part of the memory block of a base object. The
+ :attr:`_b_base_` readonly member is the root ctypes object that owns the memory
+ block.
+
+
+.. attribute:: _CData._b_needsfree_
+
+ This readonly variable is true when the ctypes data instance has allocated the
+ memory block itself, false otherwise.
+
+
+.. attribute:: _CData._objects
+
+ This member is either ``None`` or a dictionary containing Python objects that
+ need to be kept alive so that the memory block contents is kept valid. This
+ object is only exposed for debugging; never modify the contents of this
+ dictionary.
+
+
+.. _ctypes-fundamental-data-types-2:
+
+Fundamental data types
+^^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: _SimpleCData
+
+ This non-public class is the base class of all fundamental ctypes data types. It
+ is mentioned here because it contains the common attributes of the fundamental
+ ctypes data types. ``_SimpleCData`` is a subclass of ``_CData``, so it inherits
+ their methods and attributes.
+
+Instances have a single attribute:
+
+
+.. attribute:: _SimpleCData.value
+
+ This attribute contains the actual value of the instance. For integer and
+ pointer types, it is an integer, for character types, it is a single character
+ string, for character pointer types it is a Python string or unicode string.
+
+ When the ``value`` attribute is retrieved from a ctypes instance, usually a new
+ object is returned each time. ``ctypes`` does *not* implement original object
+ return, always a new object is constructed. The same is true for all other
+ ctypes object instances.
+
+Fundamental data types, when returned as foreign function call results, or, for
+example, by retrieving structure field members or array items, are transparently
+converted to native Python types. In other words, if a foreign function has a
+:attr:`restype` of :class:`c_char_p`, you will always receive a Python string,
+*not* a :class:`c_char_p` instance.
+
+Subclasses of fundamental data types do *not* inherit this behaviour. So, if a
+foreign functions :attr:`restype` is a subclass of :class:`c_void_p`, you will
+receive an instance of this subclass from the function call. Of course, you can
+get the value of the pointer by accessing the ``value`` attribute.
+
+These are the fundamental ctypes data types:
+
+
+.. class:: c_byte
+
+ Represents the C signed char datatype, and interprets the value as small
+ integer. The constructor accepts an optional integer initializer; no overflow
+ checking is done.
+
+
+.. class:: c_char
+
+ Represents the C char datatype, and interprets the value as a single character.
+ The constructor accepts an optional string initializer, the length of the string
+ must be exactly one character.
+
+
+.. class:: c_char_p
+
+ Represents the C char \* datatype, which must be a pointer to a zero-terminated
+ string. The constructor accepts an integer address, or a string.
+
+
+.. class:: c_double
+
+ Represents the C double datatype. The constructor accepts an optional float
+ initializer.
+
+
+.. class:: c_float
+
+ Represents the C double datatype. The constructor accepts an optional float
+ initializer.
+
+
+.. class:: c_int
+
+ Represents the C signed int datatype. The constructor accepts an optional
+ integer initializer; no overflow checking is done. On platforms where
+ ``sizeof(int) == sizeof(long)`` it is an alias to :class:`c_long`.
+
+
+.. class:: c_int8
+
+ Represents the C 8-bit ``signed int`` datatype. Usually an alias for
+ :class:`c_byte`.
+
+
+.. class:: c_int16
+
+ Represents the C 16-bit signed int datatype. Usually an alias for
+ :class:`c_short`.
+
+
+.. class:: c_int32
+
+ Represents the C 32-bit signed int datatype. Usually an alias for
+ :class:`c_int`.
+
+
+.. class:: c_int64
+
+ Represents the C 64-bit ``signed int`` datatype. Usually an alias for
+ :class:`c_longlong`.
+
+
+.. class:: c_long
+
+ Represents the C ``signed long`` datatype. The constructor accepts an optional
+ integer initializer; no overflow checking is done.
+
+
+.. class:: c_longlong
+
+ Represents the C ``signed long long`` datatype. The constructor accepts an
+ optional integer initializer; no overflow checking is done.
+
+
+.. class:: c_short
+
+ Represents the C ``signed short`` datatype. The constructor accepts an optional
+ integer initializer; no overflow checking is done.
+
+
+.. class:: c_size_t
+
+ Represents the C ``size_t`` datatype.
+
+
+.. class:: c_ubyte
+
+ Represents the C ``unsigned char`` datatype, it interprets the value as small
+ integer. The constructor accepts an optional integer initializer; no overflow
+ checking is done.
+
+
+.. class:: c_uint
+
+ Represents the C ``unsigned int`` datatype. The constructor accepts an optional
+ integer initializer; no overflow checking is done. On platforms where
+ ``sizeof(int) == sizeof(long)`` it is an alias for :class:`c_ulong`.
+
+
+.. class:: c_uint8
+
+ Represents the C 8-bit unsigned int datatype. Usually an alias for
+ :class:`c_ubyte`.
+
+
+.. class:: c_uint16
+
+ Represents the C 16-bit unsigned int datatype. Usually an alias for
+ :class:`c_ushort`.
+
+
+.. class:: c_uint32
+
+ Represents the C 32-bit unsigned int datatype. Usually an alias for
+ :class:`c_uint`.
+
+
+.. class:: c_uint64
+
+ Represents the C 64-bit unsigned int datatype. Usually an alias for
+ :class:`c_ulonglong`.
+
+
+.. class:: c_ulong
+
+ Represents the C ``unsigned long`` datatype. The constructor accepts an optional
+ integer initializer; no overflow checking is done.
+
+
+.. class:: c_ulonglong
+
+ Represents the C ``unsigned long long`` datatype. The constructor accepts an
+ optional integer initializer; no overflow checking is done.
+
+
+.. class:: c_ushort
+
+ Represents the C ``unsigned short`` datatype. The constructor accepts an
+ optional integer initializer; no overflow checking is done.
+
+
+.. class:: c_void_p
+
+ Represents the C ``void *`` type. The value is represented as integer. The
+ constructor accepts an optional integer initializer.
+
+
+.. class:: c_wchar
+
+ Represents the C ``wchar_t`` datatype, and interprets the value as a single
+ character unicode string. The constructor accepts an optional string
+ initializer, the length of the string must be exactly one character.
+
+
+.. class:: c_wchar_p
+
+ Represents the C ``wchar_t *`` datatype, which must be a pointer to a
+ zero-terminated wide character string. The constructor accepts an integer
+ address, or a string.
+
+
+.. class:: c_bool
+
+ Represent the C ``bool`` datatype (more accurately, _Bool from C99). Its value
+ can be True or False, and the constructor accepts any object that has a truth
+ value.
+
+ .. versionadded:: 2.6
+
+
+.. class:: HRESULT
+
+ Windows only: Represents a :class:`HRESULT` value, which contains success or
+ error information for a function or method call.
+
+
+.. class:: py_object
+
+ Represents the C ``PyObject *`` datatype. Calling this without an argument
+ creates a ``NULL`` ``PyObject *`` pointer.
+
+The ``ctypes.wintypes`` module provides quite some other Windows specific data
+types, for example ``HWND``, ``WPARAM``, or ``DWORD``. Some useful structures
+like ``MSG`` or ``RECT`` are also defined.
+
+
+.. _ctypes-structured-data-types:
+
+Structured data types
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: Union(*args, **kw)
+
+ Abstract base class for unions in native byte order.
+
+
+.. class:: BigEndianStructure(*args, **kw)
+
+ Abstract base class for structures in *big endian* byte order.
+
+
+.. class:: LittleEndianStructure(*args, **kw)
+
+ Abstract base class for structures in *little endian* byte order.
+
+Structures with non-native byte order cannot contain pointer type fields, or any
+other data types containing pointer type fields.
+
+
+.. class:: Structure(*args, **kw)
+
+ Abstract base class for structures in *native* byte order.
+
+Concrete structure and union types must be created by subclassing one of these
+types, and at least define a :attr:`_fields_` class variable. ``ctypes`` will
+create descriptors which allow reading and writing the fields by direct
+attribute accesses. These are the
+
+
+.. attribute:: Structure._fields_
+
+ A sequence defining the structure fields. The items must be 2-tuples or
+ 3-tuples. The first item is the name of the field, the second item specifies
+ the type of the field; it can be any ctypes data type.
+
+ For integer type fields like :class:`c_int`, a third optional item can be given.
+ It must be a small positive integer defining the bit width of the field.
+
+ Field names must be unique within one structure or union. This is not checked,
+ only one field can be accessed when names are repeated.
+
+ It is possible to define the :attr:`_fields_` class variable *after* the class
+ statement that defines the Structure subclass, this allows to create data types
+ that directly or indirectly reference themselves::
+
+ class List(Structure):
+ pass
+ List._fields_ = [("pnext", POINTER(List)),
+ ...
+ ]
+
+ The :attr:`_fields_` class variable must, however, be defined before the type is
+ first used (an instance is created, ``sizeof()`` is called on it, and so on).
+ Later assignments to the :attr:`_fields_` class variable will raise an
+ AttributeError.
+
+ Structure and union subclass constructors accept both positional and named
+ arguments. Positional arguments are used to initialize the fields in the same
+ order as they appear in the :attr:`_fields_` definition, named arguments are
+ used to initialize the fields with the corresponding name.
+
+ It is possible to defined sub-subclasses of structure types, they inherit the
+ fields of the base class plus the :attr:`_fields_` defined in the sub-subclass,
+ if any.
+
+
+.. attribute:: Structure._pack_
+
+ An optional small integer that allows to override the alignment of structure
+ fields in the instance. :attr:`_pack_` must already be defined when
+ :attr:`_fields_` is assigned, otherwise it will have no effect.
+
+
+.. attribute:: Structure._anonymous_
+
+ An optional sequence that lists the names of unnamed (anonymous) fields.
+ ``_anonymous_`` must be already defined when :attr:`_fields_` is assigned,
+ otherwise it will have no effect.
+
+ The fields listed in this variable must be structure or union type fields.
+ ``ctypes`` will create descriptors in the structure type that allows to access
+ the nested fields directly, without the need to create the structure or union
+ field.
+
+ Here is an example type (Windows)::
+
+ class _U(Union):
+ _fields_ = [("lptdesc", POINTER(TYPEDESC)),
+ ("lpadesc", POINTER(ARRAYDESC)),
+ ("hreftype", HREFTYPE)]
+
+ class TYPEDESC(Structure):
+ _fields_ = [("u", _U),
+ ("vt", VARTYPE)]
+
+ _anonymous_ = ("u",)
+
+ The ``TYPEDESC`` structure describes a COM data type, the ``vt`` field specifies
+ which one of the union fields is valid. Since the ``u`` field is defined as
+ anonymous field, it is now possible to access the members directly off the
+ TYPEDESC instance. ``td.lptdesc`` and ``td.u.lptdesc`` are equivalent, but the
+ former is faster since it does not need to create a temporary union instance::
+
+ td = TYPEDESC()
+ td.vt = VT_PTR
+ td.lptdesc = POINTER(some_type)
+ td.u.lptdesc = POINTER(some_type)
+
+It is possible to defined sub-subclasses of structures, they inherit the fields
+of the base class. If the subclass definition has a separate :attr:`_fields_`
+variable, the fields specified in this are appended to the fields of the base
+class.
+
+Structure and union constructors accept both positional and keyword arguments.
+Positional arguments are used to initialize member fields in the same order as
+they are appear in :attr:`_fields_`. Keyword arguments in the constructor are
+interpreted as attribute assignments, so they will initialize :attr:`_fields_`
+with the same name, or create new attributes for names not present in
+:attr:`_fields_`.
+
+
+.. _ctypes-arrays-pointers:
+
+Arrays and pointers
+^^^^^^^^^^^^^^^^^^^
+
+Not yet written - please see the sections :ref:`ctypes-pointers` and
+section :ref:`ctypes-arrays` in the tutorial.
+
diff --git a/Doc/library/curses.ascii.rst b/Doc/library/curses.ascii.rst
new file mode 100644
index 0000000000..0a45c2a339
--- /dev/null
+++ b/Doc/library/curses.ascii.rst
@@ -0,0 +1,228 @@
+
+:mod:`curses.ascii` --- Utilities for ASCII characters
+======================================================
+
+.. module:: curses.ascii
+ :synopsis: Constants and set-membership functions for ASCII characters.
+.. moduleauthor:: Eric S. Raymond <esr@thyrsus.com>
+.. sectionauthor:: Eric S. Raymond <esr@thyrsus.com>
+
+
+.. versionadded:: 1.6
+
+The :mod:`curses.ascii` module supplies name constants for ASCII characters and
+functions to test membership in various ASCII character classes. The constants
+supplied are names for control characters as follows:
+
++--------------+----------------------------------------------+
+| Name | Meaning |
++==============+==============================================+
+| :const:`NUL` | |
++--------------+----------------------------------------------+
+| :const:`SOH` | Start of heading, console interrupt |
++--------------+----------------------------------------------+
+| :const:`STX` | Start of text |
++--------------+----------------------------------------------+
+| :const:`ETX` | End of text |
++--------------+----------------------------------------------+
+| :const:`EOT` | End of transmission |
++--------------+----------------------------------------------+
+| :const:`ENQ` | Enquiry, goes with :const:`ACK` flow control |
++--------------+----------------------------------------------+
+| :const:`ACK` | Acknowledgement |
++--------------+----------------------------------------------+
+| :const:`BEL` | Bell |
++--------------+----------------------------------------------+
+| :const:`BS` | Backspace |
++--------------+----------------------------------------------+
+| :const:`TAB` | Tab |
++--------------+----------------------------------------------+
+| :const:`HT` | Alias for :const:`TAB`: "Horizontal tab" |
++--------------+----------------------------------------------+
+| :const:`LF` | Line feed |
++--------------+----------------------------------------------+
+| :const:`NL` | Alias for :const:`LF`: "New line" |
++--------------+----------------------------------------------+
+| :const:`VT` | Vertical tab |
++--------------+----------------------------------------------+
+| :const:`FF` | Form feed |
++--------------+----------------------------------------------+
+| :const:`CR` | Carriage return |
++--------------+----------------------------------------------+
+| :const:`SO` | Shift-out, begin alternate character set |
++--------------+----------------------------------------------+
+| :const:`SI` | Shift-in, resume default character set |
++--------------+----------------------------------------------+
+| :const:`DLE` | Data-link escape |
++--------------+----------------------------------------------+
+| :const:`DC1` | XON, for flow control |
++--------------+----------------------------------------------+
+| :const:`DC2` | Device control 2, block-mode flow control |
++--------------+----------------------------------------------+
+| :const:`DC3` | XOFF, for flow control |
++--------------+----------------------------------------------+
+| :const:`DC4` | Device control 4 |
++--------------+----------------------------------------------+
+| :const:`NAK` | Negative acknowledgement |
++--------------+----------------------------------------------+
+| :const:`SYN` | Synchronous idle |
++--------------+----------------------------------------------+
+| :const:`ETB` | End transmission block |
++--------------+----------------------------------------------+
+| :const:`CAN` | Cancel |
++--------------+----------------------------------------------+
+| :const:`EM` | End of medium |
++--------------+----------------------------------------------+
+| :const:`SUB` | Substitute |
++--------------+----------------------------------------------+
+| :const:`ESC` | Escape |
++--------------+----------------------------------------------+
+| :const:`FS` | File separator |
++--------------+----------------------------------------------+
+| :const:`GS` | Group separator |
++--------------+----------------------------------------------+
+| :const:`RS` | Record separator, block-mode terminator |
++--------------+----------------------------------------------+
+| :const:`US` | Unit separator |
++--------------+----------------------------------------------+
+| :const:`SP` | Space |
++--------------+----------------------------------------------+
+| :const:`DEL` | Delete |
++--------------+----------------------------------------------+
+
+Note that many of these have little practical significance in modern usage. The
+mnemonics derive from teleprinter conventions that predate digital computers.
+
+The module supplies the following functions, patterned on those in the standard
+C library:
+
+
+.. function:: isalnum(c)
+
+ Checks for an ASCII alphanumeric character; it is equivalent to ``isalpha(c) or
+ isdigit(c)``.
+
+
+.. function:: isalpha(c)
+
+ Checks for an ASCII alphabetic character; it is equivalent to ``isupper(c) or
+ islower(c)``.
+
+
+.. function:: isascii(c)
+
+ Checks for a character value that fits in the 7-bit ASCII set.
+
+
+.. function:: isblank(c)
+
+ Checks for an ASCII whitespace character.
+
+
+.. function:: iscntrl(c)
+
+ Checks for an ASCII control character (in the range 0x00 to 0x1f).
+
+
+.. function:: isdigit(c)
+
+ Checks for an ASCII decimal digit, ``'0'`` through ``'9'``. This is equivalent
+ to ``c in string.digits``.
+
+
+.. function:: isgraph(c)
+
+ Checks for ASCII any printable character except space.
+
+
+.. function:: islower(c)
+
+ Checks for an ASCII lower-case character.
+
+
+.. function:: isprint(c)
+
+ Checks for any ASCII printable character including space.
+
+
+.. function:: ispunct(c)
+
+ Checks for any printable ASCII character which is not a space or an alphanumeric
+ character.
+
+
+.. function:: isspace(c)
+
+ Checks for ASCII white-space characters; space, line feed, carriage return, form
+ feed, horizontal tab, vertical tab.
+
+
+.. function:: isupper(c)
+
+ Checks for an ASCII uppercase letter.
+
+
+.. function:: isxdigit(c)
+
+ Checks for an ASCII hexadecimal digit. This is equivalent to ``c in
+ string.hexdigits``.
+
+
+.. function:: isctrl(c)
+
+ Checks for an ASCII control character (ordinal values 0 to 31).
+
+
+.. function:: ismeta(c)
+
+ Checks for a non-ASCII character (ordinal values 0x80 and above).
+
+These functions accept either integers or strings; when the argument is a
+string, it is first converted using the built-in function :func:`ord`.
+
+Note that all these functions check ordinal bit values derived from the first
+character of the string you pass in; they do not actually know anything about
+the host machine's character encoding. For functions that know about the
+character encoding (and handle internationalization properly) see the
+:mod:`string` module.
+
+The following two functions take either a single-character string or integer
+byte value; they return a value of the same type.
+
+
+.. function:: ascii(c)
+
+ Return the ASCII value corresponding to the low 7 bits of *c*.
+
+
+.. function:: ctrl(c)
+
+ Return the control character corresponding to the given character (the character
+ bit value is bitwise-anded with 0x1f).
+
+
+.. function:: alt(c)
+
+ Return the 8-bit character corresponding to the given ASCII character (the
+ character bit value is bitwise-ored with 0x80).
+
+The following function takes either a single-character string or integer value;
+it returns a string.
+
+
+.. function:: unctrl(c)
+
+ Return a string representation of the ASCII character *c*. If *c* is printable,
+ this string is the character itself. If the character is a control character
+ (0x00-0x1f) the string consists of a caret (``'^'``) followed by the
+ corresponding uppercase letter. If the character is an ASCII delete (0x7f) the
+ string is ``'^?'``. If the character has its meta bit (0x80) set, the meta bit
+ is stripped, the preceding rules applied, and ``'!'`` prepended to the result.
+
+
+.. data:: controlnames
+
+ A 33-element string array that contains the ASCII mnemonics for the thirty-two
+ ASCII control characters from 0 (NUL) to 0x1f (US), in order, plus the mnemonic
+ ``SP`` for the space character.
+
diff --git a/Doc/library/curses.panel.rst b/Doc/library/curses.panel.rst
new file mode 100644
index 0000000000..59e5b86f19
--- /dev/null
+++ b/Doc/library/curses.panel.rst
@@ -0,0 +1,119 @@
+
+:mod:`curses.panel` --- A panel stack extension for curses.
+===========================================================
+
+.. module:: curses.panel
+ :synopsis: A panel stack extension that adds depth to curses windows.
+.. sectionauthor:: A.M. Kuchling <amk@amk.ca>
+
+
+Panels are windows with the added feature of depth, so they can be stacked on
+top of each other, and only the visible portions of each window will be
+displayed. Panels can be added, moved up or down in the stack, and removed.
+
+
+.. _cursespanel-functions:
+
+Functions
+---------
+
+The module :mod:`curses.panel` defines the following functions:
+
+
+.. function:: bottom_panel()
+
+ Returns the bottom panel in the panel stack.
+
+
+.. function:: new_panel(win)
+
+ Returns a panel object, associating it with the given window *win*. Be aware
+ that you need to keep the returned panel object referenced explicitly. If you
+ don't, the panel object is garbage collected and removed from the panel stack.
+
+
+.. function:: top_panel()
+
+ Returns the top panel in the panel stack.
+
+
+.. function:: update_panels()
+
+ Updates the virtual screen after changes in the panel stack. This does not call
+ :func:`curses.doupdate`, so you'll have to do this yourself.
+
+
+.. _curses-panel-objects:
+
+Panel Objects
+-------------
+
+Panel objects, as returned by :func:`new_panel` above, are windows with a
+stacking order. There's always a window associated with a panel which determines
+the content, while the panel methods are responsible for the window's depth in
+the panel stack.
+
+Panel objects have the following methods:
+
+
+.. method:: Panel.above()
+
+ Returns the panel above the current panel.
+
+
+.. method:: Panel.below()
+
+ Returns the panel below the current panel.
+
+
+.. method:: Panel.bottom()
+
+ Push the panel to the bottom of the stack.
+
+
+.. method:: Panel.hidden()
+
+ Returns true if the panel is hidden (not visible), false otherwise.
+
+
+.. method:: Panel.hide()
+
+ Hide the panel. This does not delete the object, it just makes the window on
+ screen invisible.
+
+
+.. method:: Panel.move(y, x)
+
+ Move the panel to the screen coordinates ``(y, x)``.
+
+
+.. method:: Panel.replace(win)
+
+ Change the window associated with the panel to the window *win*.
+
+
+.. method:: Panel.set_userptr(obj)
+
+ Set the panel's user pointer to *obj*. This is used to associate an arbitrary
+ piece of data with the panel, and can be any Python object.
+
+
+.. method:: Panel.show()
+
+ Display the panel (which might have been hidden).
+
+
+.. method:: Panel.top()
+
+ Push panel to the top of the stack.
+
+
+.. method:: Panel.userptr()
+
+ Returns the user pointer for the panel. This might be any Python object.
+
+
+.. method:: Panel.window()
+
+ Returns the window object associated with the panel.
+
diff --git a/Doc/library/curses.rst b/Doc/library/curses.rst
new file mode 100644
index 0000000000..91af757108
--- /dev/null
+++ b/Doc/library/curses.rst
@@ -0,0 +1,1679 @@
+
+:mod:`curses` --- Terminal handling for character-cell displays
+===============================================================
+
+.. module:: curses
+ :synopsis: An interface to the curses library, providing portable terminal handling.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+.. sectionauthor:: Eric Raymond <esr@thyrsus.com>
+
+
+.. versionchanged:: 1.6
+ Added support for the ``ncurses`` library and converted to a package.
+
+The :mod:`curses` module provides an interface to the curses library, the
+de-facto standard for portable advanced terminal handling.
+
+While curses is most widely used in the Unix environment, versions are available
+for DOS, OS/2, and possibly other systems as well. This extension module is
+designed to match the API of ncurses, an open-source curses library hosted on
+Linux and the BSD variants of Unix.
+
+
+.. seealso::
+
+ Module :mod:`curses.ascii`
+ Utilities for working with ASCII characters, regardless of your locale settings.
+
+ Module :mod:`curses.panel`
+ A panel stack extension that adds depth to curses windows.
+
+ Module :mod:`curses.textpad`
+ Editable text widget for curses supporting :program:`Emacs`\ -like bindings.
+
+ Module :mod:`curses.wrapper`
+ Convenience function to ensure proper terminal setup and resetting on
+ application entry and exit.
+
+ `Curses Programming with Python <http://www.python.org/doc/howto/curses/curses.html>`_
+ Tutorial material on using curses with Python, by Andrew Kuchling and Eric
+ Raymond, is available on the Python Web site.
+
+ The :file:`Demo/curses/` directory in the Python source distribution contains
+ some example programs using the curses bindings provided by this module.
+
+
+.. _curses-functions:
+
+Functions
+---------
+
+The module :mod:`curses` defines the following exception:
+
+
+.. exception:: error
+
+ Exception raised when a curses library function returns an error.
+
+.. note::
+
+ Whenever *x* or *y* arguments to a function or a method are optional, they
+ default to the current cursor location. Whenever *attr* is optional, it defaults
+ to :const:`A_NORMAL`.
+
+The module :mod:`curses` defines the following functions:
+
+
+.. function:: baudrate()
+
+ Returns the output speed of the terminal in bits per second. On software
+ terminal emulators it will have a fixed high value. Included for historical
+ reasons; in former times, it was used to write output loops for time delays and
+ occasionally to change interfaces depending on the line speed.
+
+
+.. function:: beep()
+
+ Emit a short attention sound.
+
+
+.. function:: can_change_color()
+
+ Returns true or false, depending on whether the programmer can change the colors
+ displayed by the terminal.
+
+
+.. function:: cbreak()
+
+ Enter cbreak mode. In cbreak mode (sometimes called "rare" mode) normal tty
+ line buffering is turned off and characters are available to be read one by one.
+ However, unlike raw mode, special characters (interrupt, quit, suspend, and flow
+ control) retain their effects on the tty driver and calling program. Calling
+ first :func:`raw` then :func:`cbreak` leaves the terminal in cbreak mode.
+
+
+.. function:: color_content(color_number)
+
+ Returns the intensity of the red, green, and blue (RGB) components in the color
+ *color_number*, which must be between ``0`` and :const:`COLORS`. A 3-tuple is
+ returned, containing the R,G,B values for the given color, which will be between
+ ``0`` (no component) and ``1000`` (maximum amount of component).
+
+
+.. function:: color_pair(color_number)
+
+ Returns the attribute value for displaying text in the specified color. This
+ attribute value can be combined with :const:`A_STANDOUT`, :const:`A_REVERSE`,
+ and the other :const:`A_\*` attributes. :func:`pair_number` is the counterpart
+ to this function.
+
+
+.. function:: curs_set(visibility)
+
+ Sets the cursor state. *visibility* can be set to 0, 1, or 2, for invisible,
+ normal, or very visible. If the terminal supports the visibility requested, the
+ previous cursor state is returned; otherwise, an exception is raised. On many
+ terminals, the "visible" mode is an underline cursor and the "very visible" mode
+ is a block cursor.
+
+
+.. function:: def_prog_mode()
+
+ Saves the current terminal mode as the "program" mode, the mode when the running
+ program is using curses. (Its counterpart is the "shell" mode, for when the
+ program is not in curses.) Subsequent calls to :func:`reset_prog_mode` will
+ restore this mode.
+
+
+.. function:: def_shell_mode()
+
+ Saves the current terminal mode as the "shell" mode, the mode when the running
+ program is not using curses. (Its counterpart is the "program" mode, when the
+ program is using curses capabilities.) Subsequent calls to
+ :func:`reset_shell_mode` will restore this mode.
+
+
+.. function:: delay_output(ms)
+
+ Inserts an *ms* millisecond pause in output.
+
+
+.. function:: doupdate()
+
+ Update the physical screen. The curses library keeps two data structures, one
+ representing the current physical screen contents and a virtual screen
+ representing the desired next state. The :func:`doupdate` ground updates the
+ physical screen to match the virtual screen.
+
+ The virtual screen may be updated by a :meth:`noutrefresh` call after write
+ operations such as :meth:`addstr` have been performed on a window. The normal
+ :meth:`refresh` call is simply :meth:`noutrefresh` followed by :func:`doupdate`;
+ if you have to update multiple windows, you can speed performance and perhaps
+ reduce screen flicker by issuing :meth:`noutrefresh` calls on all windows,
+ followed by a single :func:`doupdate`.
+
+
+.. function:: echo()
+
+ Enter echo mode. In echo mode, each character input is echoed to the screen as
+ it is entered.
+
+
+.. function:: endwin()
+
+ De-initialize the library, and return terminal to normal status.
+
+
+.. function:: erasechar()
+
+ Returns the user's current erase character. Under Unix operating systems this
+ is a property of the controlling tty of the curses program, and is not set by
+ the curses library itself.
+
+
+.. function:: filter()
+
+ The :func:`filter` routine, if used, must be called before :func:`initscr` is
+ called. The effect is that, during those calls, LINES is set to 1; the
+ capabilities clear, cup, cud, cud1, cuu1, cuu, vpa are disabled; and the home
+ string is set to the value of cr. The effect is that the cursor is confined to
+ the current line, and so are screen updates. This may be used for enabling
+ character-at-a-time line editing without touching the rest of the screen.
+
+
+.. function:: flash()
+
+ Flash the screen. That is, change it to reverse-video and then change it back
+ in a short interval. Some people prefer such as 'visible bell' to the audible
+ attention signal produced by :func:`beep`.
+
+
+.. function:: flushinp()
+
+ Flush all input buffers. This throws away any typeahead that has been typed
+ by the user and has not yet been processed by the program.
+
+
+.. function:: getmouse()
+
+ After :meth:`getch` returns :const:`KEY_MOUSE` to signal a mouse event, this
+ method should be call to retrieve the queued mouse event, represented as a
+ 5-tuple ``(id, x, y, z, bstate)``. *id* is an ID value used to distinguish
+ multiple devices, and *x*, *y*, *z* are the event's coordinates. (*z* is
+ currently unused.). *bstate* is an integer value whose bits will be set to
+ indicate the type of event, and will be the bitwise OR of one or more of the
+ following constants, where *n* is the button number from 1 to 4:
+ :const:`BUTTONn_PRESSED`, :const:`BUTTONn_RELEASED`, :const:`BUTTONn_CLICKED`,
+ :const:`BUTTONn_DOUBLE_CLICKED`, :const:`BUTTONn_TRIPLE_CLICKED`,
+ :const:`BUTTON_SHIFT`, :const:`BUTTON_CTRL`, :const:`BUTTON_ALT`.
+
+
+.. function:: getsyx()
+
+ Returns the current coordinates of the virtual screen cursor in y and x. If
+ leaveok is currently true, then -1,-1 is returned.
+
+
+.. function:: getwin(file)
+
+ Reads window related data stored in the file by an earlier :func:`putwin` call.
+ The routine then creates and initializes a new window using that data, returning
+ the new window object.
+
+
+.. function:: has_colors()
+
+ Returns true if the terminal can display colors; otherwise, it returns false.
+
+
+.. function:: has_ic()
+
+ Returns true if the terminal has insert- and delete- character capabilities.
+ This function is included for historical reasons only, as all modern software
+ terminal emulators have such capabilities.
+
+
+.. function:: has_il()
+
+ Returns true if the terminal has insert- and delete-line capabilities, or can
+ simulate them using scrolling regions. This function is included for
+ historical reasons only, as all modern software terminal emulators have such
+ capabilities.
+
+
+.. function:: has_key(ch)
+
+ Takes a key value *ch*, and returns true if the current terminal type recognizes
+ a key with that value.
+
+
+.. function:: halfdelay(tenths)
+
+ Used for half-delay mode, which is similar to cbreak mode in that characters
+ typed by the user are immediately available to the program. However, after
+ blocking for *tenths* tenths of seconds, an exception is raised if nothing has
+ been typed. The value of *tenths* must be a number between 1 and 255. Use
+ :func:`nocbreak` to leave half-delay mode.
+
+
+.. function:: init_color(color_number, r, g, b)
+
+ Changes the definition of a color, taking the number of the color to be changed
+ followed by three RGB values (for the amounts of red, green, and blue
+ components). The value of *color_number* must be between ``0`` and
+ :const:`COLORS`. Each of *r*, *g*, *b*, must be a value between ``0`` and
+ ``1000``. When :func:`init_color` is used, all occurrences of that color on the
+ screen immediately change to the new definition. This function is a no-op on
+ most terminals; it is active only if :func:`can_change_color` returns ``1``.
+
+
+.. function:: init_pair(pair_number, fg, bg)
+
+ Changes the definition of a color-pair. It takes three arguments: the number of
+ the color-pair to be changed, the foreground color number, and the background
+ color number. The value of *pair_number* must be between ``1`` and
+ ``COLOR_PAIRS - 1`` (the ``0`` color pair is wired to white on black and cannot
+ be changed). The value of *fg* and *bg* arguments must be between ``0`` and
+ :const:`COLORS`. If the color-pair was previously initialized, the screen is
+ refreshed and all occurrences of that color-pair are changed to the new
+ definition.
+
+
+.. function:: initscr()
+
+ Initialize the library. Returns a :class:`WindowObject` which represents the
+ whole screen.
+
+ .. note::
+
+ If there is an error opening the terminal, the underlying curses library may
+ cause the interpreter to exit.
+
+
+.. function:: isendwin()
+
+ Returns true if :func:`endwin` has been called (that is, the curses library has
+ been deinitialized).
+
+
+.. function:: keyname(k)
+
+ Return the name of the key numbered *k*. The name of a key generating printable
+ ASCII character is the key's character. The name of a control-key combination
+ is a two-character string consisting of a caret followed by the corresponding
+ printable ASCII character. The name of an alt-key combination (128-255) is a
+ string consisting of the prefix 'M-' followed by the name of the corresponding
+ ASCII character.
+
+
+.. function:: killchar()
+
+ Returns the user's current line kill character. Under Unix operating systems
+ this is a property of the controlling tty of the curses program, and is not set
+ by the curses library itself.
+
+
+.. function:: longname()
+
+ Returns a string containing the terminfo long name field describing the current
+ terminal. The maximum length of a verbose description is 128 characters. It is
+ defined only after the call to :func:`initscr`.
+
+
+.. function:: meta(yes)
+
+ If *yes* is 1, allow 8-bit characters to be input. If *yes* is 0, allow only
+ 7-bit chars.
+
+
+.. function:: mouseinterval(interval)
+
+ Sets the maximum time in milliseconds that can elapse between press and release
+ events in order for them to be recognized as a click, and returns the previous
+ interval value. The default value is 200 msec, or one fifth of a second.
+
+
+.. function:: mousemask(mousemask)
+
+ Sets the mouse events to be reported, and returns a tuple ``(availmask,
+ oldmask)``. *availmask* indicates which of the specified mouse events can be
+ reported; on complete failure it returns 0. *oldmask* is the previous value of
+ the given window's mouse event mask. If this function is never called, no mouse
+ events are ever reported.
+
+
+.. function:: napms(ms)
+
+ Sleep for *ms* milliseconds.
+
+
+.. function:: newpad(nlines, ncols)
+
+ Creates and returns a pointer to a new pad data structure with the given number
+ of lines and columns. A pad is returned as a window object.
+
+ A pad is like a window, except that it is not restricted by the screen size, and
+ is not necessarily associated with a particular part of the screen. Pads can be
+ used when a large window is needed, and only a part of the window will be on the
+ screen at one time. Automatic refreshes of pads (such as from scrolling or
+ echoing of input) do not occur. The :meth:`refresh` and :meth:`noutrefresh`
+ methods of a pad require 6 arguments to specify the part of the pad to be
+ displayed and the location on the screen to be used for the display. The
+ arguments are pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol; the p
+ arguments refer to the upper left corner of the pad region to be displayed and
+ the s arguments define a clipping box on the screen within which the pad region
+ is to be displayed.
+
+
+.. function:: newwin([nlines, ncols,] begin_y, begin_x)
+
+ Return a new window, whose left-upper corner is at ``(begin_y, begin_x)``, and
+ whose height/width is *nlines*/*ncols*.
+
+ By default, the window will extend from the specified position to the lower
+ right corner of the screen.
+
+
+.. function:: nl()
+
+ Enter newline mode. This mode translates the return key into newline on input,
+ and translates newline into return and line-feed on output. Newline mode is
+ initially on.
+
+
+.. function:: nocbreak()
+
+ Leave cbreak mode. Return to normal "cooked" mode with line buffering.
+
+
+.. function:: noecho()
+
+ Leave echo mode. Echoing of input characters is turned off.
+
+
+.. function:: nonl()
+
+ Leave newline mode. Disable translation of return into newline on input, and
+ disable low-level translation of newline into newline/return on output (but this
+ does not change the behavior of ``addch('\n')``, which always does the
+ equivalent of return and line feed on the virtual screen). With translation
+ off, curses can sometimes speed up vertical motion a little; also, it will be
+ able to detect the return key on input.
+
+
+.. function:: noqiflush()
+
+ When the noqiflush routine is used, normal flush of input and output queues
+ associated with the INTR, QUIT and SUSP characters will not be done. You may
+ want to call :func:`noqiflush` in a signal handler if you want output to
+ continue as though the interrupt had not occurred, after the handler exits.
+
+
+.. function:: noraw()
+
+ Leave raw mode. Return to normal "cooked" mode with line buffering.
+
+
+.. function:: pair_content(pair_number)
+
+ Returns a tuple ``(fg, bg)`` containing the colors for the requested color pair.
+ The value of *pair_number* must be between ``1`` and ``COLOR_PAIRS - 1``.
+
+
+.. function:: pair_number(attr)
+
+ Returns the number of the color-pair set by the attribute value *attr*.
+ :func:`color_pair` is the counterpart to this function.
+
+
+.. function:: putp(string)
+
+ Equivalent to ``tputs(str, 1, putchar)``; emits the value of a specified
+ terminfo capability for the current terminal. Note that the output of putp
+ always goes to standard output.
+
+
+.. function:: qiflush( [flag] )
+
+ If *flag* is false, the effect is the same as calling :func:`noqiflush`. If
+ *flag* is true, or no argument is provided, the queues will be flushed when
+ these control characters are read.
+
+
+.. function:: raw()
+
+ Enter raw mode. In raw mode, normal line buffering and processing of
+ interrupt, quit, suspend, and flow control keys are turned off; characters are
+ presented to curses input functions one by one.
+
+
+.. function:: reset_prog_mode()
+
+ Restores the terminal to "program" mode, as previously saved by
+ :func:`def_prog_mode`.
+
+
+.. function:: reset_shell_mode()
+
+ Restores the terminal to "shell" mode, as previously saved by
+ :func:`def_shell_mode`.
+
+
+.. function:: setsyx(y, x)
+
+ Sets the virtual screen cursor to *y*, *x*. If *y* and *x* are both -1, then
+ leaveok is set.
+
+
+.. function:: setupterm([termstr, fd])
+
+ Initializes the terminal. *termstr* is a string giving the terminal name; if
+ omitted, the value of the TERM environment variable will be used. *fd* is the
+ file descriptor to which any initialization sequences will be sent; if not
+ supplied, the file descriptor for ``sys.stdout`` will be used.
+
+
+.. function:: start_color()
+
+ Must be called if the programmer wants to use colors, and before any other color
+ manipulation routine is called. It is good practice to call this routine right
+ after :func:`initscr`.
+
+ :func:`start_color` initializes eight basic colors (black, red, green, yellow,
+ blue, magenta, cyan, and white), and two global variables in the :mod:`curses`
+ module, :const:`COLORS` and :const:`COLOR_PAIRS`, containing the maximum number
+ of colors and color-pairs the terminal can support. It also restores the colors
+ on the terminal to the values they had when the terminal was just turned on.
+
+
+.. function:: termattrs()
+
+ Returns a logical OR of all video attributes supported by the terminal. This
+ information is useful when a curses program needs complete control over the
+ appearance of the screen.
+
+
+.. function:: termname()
+
+ Returns the value of the environment variable TERM, truncated to 14 characters.
+
+
+.. function:: tigetflag(capname)
+
+ Returns the value of the Boolean capability corresponding to the terminfo
+ capability name *capname*. The value ``-1`` is returned if *capname* is not a
+ Boolean capability, or ``0`` if it is canceled or absent from the terminal
+ description.
+
+
+.. function:: tigetnum(capname)
+
+ Returns the value of the numeric capability corresponding to the terminfo
+ capability name *capname*. The value ``-2`` is returned if *capname* is not a
+ numeric capability, or ``-1`` if it is canceled or absent from the terminal
+ description.
+
+
+.. function:: tigetstr(capname)
+
+ Returns the value of the string capability corresponding to the terminfo
+ capability name *capname*. ``None`` is returned if *capname* is not a string
+ capability, or is canceled or absent from the terminal description.
+
+
+.. function:: tparm(str[,...])
+
+ Instantiates the string *str* with the supplied parameters, where *str* should
+ be a parameterized string obtained from the terminfo database. E.g.
+ ``tparm(tigetstr("cup"), 5, 3)`` could result in ``'\033[6;4H'``, the exact
+ result depending on terminal type.
+
+
+.. function:: typeahead(fd)
+
+ Specifies that the file descriptor *fd* be used for typeahead checking. If *fd*
+ is ``-1``, then no typeahead checking is done.
+
+ The curses library does "line-breakout optimization" by looking for typeahead
+ periodically while updating the screen. If input is found, and it is coming
+ from a tty, the current update is postponed until refresh or doupdate is called
+ again, allowing faster response to commands typed in advance. This function
+ allows specifying a different file descriptor for typeahead checking.
+
+
+.. function:: unctrl(ch)
+
+ Returns a string which is a printable representation of the character *ch*.
+ Control characters are displayed as a caret followed by the character, for
+ example as ``^C``. Printing characters are left as they are.
+
+
+.. function:: ungetch(ch)
+
+ Push *ch* so the next :meth:`getch` will return it.
+
+ .. note::
+
+ Only one *ch* can be pushed before :meth:`getch` is called.
+
+
+.. function:: ungetmouse(id, x, y, z, bstate)
+
+ Push a :const:`KEY_MOUSE` event onto the input queue, associating the given
+ state data with it.
+
+
+.. function:: use_env(flag)
+
+ If used, this function should be called before :func:`initscr` or newterm are
+ called. When *flag* is false, the values of lines and columns specified in the
+ terminfo database will be used, even if environment variables :envvar:`LINES`
+ and :envvar:`COLUMNS` (used by default) are set, or if curses is running in a
+ window (in which case default behavior would be to use the window size if
+ :envvar:`LINES` and :envvar:`COLUMNS` are not set).
+
+
+.. function:: use_default_colors()
+
+ Allow use of default values for colors on terminals supporting this feature. Use
+ this to support transparency in your application. The default color is assigned
+ to the color number -1. After calling this function, ``init_pair(x,
+ curses.COLOR_RED, -1)`` initializes, for instance, color pair *x* to a red
+ foreground color on the default background.
+
+
+.. _curses-window-objects:
+
+Window Objects
+--------------
+
+Window objects, as returned by :func:`initscr` and :func:`newwin` above, have
+the following methods:
+
+
+.. method:: window.addch([y, x,] ch[, attr])
+
+ .. note::
+
+ A *character* means a C character (an ASCII code), rather then a Python
+ character (a string of length 1). (This note is true whenever the documentation
+ mentions a character.) The builtin :func:`ord` is handy for conveying strings to
+ codes.
+
+ Paint character *ch* at ``(y, x)`` with attributes *attr*, overwriting any
+ character previously painter at that location. By default, the character
+ position and attributes are the current settings for the window object.
+
+
+.. method:: window.addnstr([y, x,] str, n[, attr])
+
+ Paint at most *n* characters of the string *str* at ``(y, x)`` with attributes
+ *attr*, overwriting anything previously on the display.
+
+
+.. method:: window.addstr([y, x,] str[, attr])
+
+ Paint the string *str* at ``(y, x)`` with attributes *attr*, overwriting
+ anything previously on the display.
+
+
+.. method:: window.attroff(attr)
+
+ Remove attribute *attr* from the "background" set applied to all writes to the
+ current window.
+
+
+.. method:: window.attron(attr)
+
+ Add attribute *attr* from the "background" set applied to all writes to the
+ current window.
+
+
+.. method:: window.attrset(attr)
+
+ Set the "background" set of attributes to *attr*. This set is initially 0 (no
+ attributes).
+
+
+.. method:: window.bkgd(ch[, attr])
+
+ Sets the background property of the window to the character *ch*, with
+ attributes *attr*. The change is then applied to every character position in
+ that window:
+
+ * The attribute of every character in the window is changed to the new
+ background attribute.
+
+ * Wherever the former background character appears, it is changed to the new
+ background character.
+
+
+.. method:: window.bkgdset(ch[, attr])
+
+ Sets the window's background. A window's background consists of a character and
+ any combination of attributes. The attribute part of the background is combined
+ (OR'ed) with all non-blank characters that are written into the window. Both
+ the character and attribute parts of the background are combined with the blank
+ characters. The background becomes a property of the character and moves with
+ the character through any scrolling and insert/delete line/character operations.
+
+
+.. method:: window.border([ls[, rs[, ts[, bs[, tl[, tr[, bl[, br]]]]]]]])
+
+ Draw a border around the edges of the window. Each parameter specifies the
+ character to use for a specific part of the border; see the table below for more
+ details. The characters can be specified as integers or as one-character
+ strings.
+
+ .. note::
+
+ A ``0`` value for any parameter will cause the default character to be used for
+ that parameter. Keyword parameters can *not* be used. The defaults are listed
+ in this table:
+
+ +-----------+---------------------+-----------------------+
+ | Parameter | Description | Default value |
+ +===========+=====================+=======================+
+ | *ls* | Left side | :const:`ACS_VLINE` |
+ +-----------+---------------------+-----------------------+
+ | *rs* | Right side | :const:`ACS_VLINE` |
+ +-----------+---------------------+-----------------------+
+ | *ts* | Top | :const:`ACS_HLINE` |
+ +-----------+---------------------+-----------------------+
+ | *bs* | Bottom | :const:`ACS_HLINE` |
+ +-----------+---------------------+-----------------------+
+ | *tl* | Upper-left corner | :const:`ACS_ULCORNER` |
+ +-----------+---------------------+-----------------------+
+ | *tr* | Upper-right corner | :const:`ACS_URCORNER` |
+ +-----------+---------------------+-----------------------+
+ | *bl* | Bottom-left corner | :const:`ACS_LLCORNER` |
+ +-----------+---------------------+-----------------------+
+ | *br* | Bottom-right corner | :const:`ACS_LRCORNER` |
+ +-----------+---------------------+-----------------------+
+
+
+.. method:: window.box([vertch, horch])
+
+ Similar to :meth:`border`, but both *ls* and *rs* are *vertch* and both *ts* and
+ bs are *horch*. The default corner characters are always used by this function.
+
+
+.. method:: window.chgat([y, x, ] [num,] attr)
+
+ Sets the attributes of *num* characters at the current cursor position, or at
+ position ``(y, x)`` if supplied. If no value of *num* is given or *num* = -1,
+ the attribute will be set on all the characters to the end of the line. This
+ function does not move the cursor. The changed line will be touched using the
+ :meth:`touchline` method so that the contents will be redisplayed by the next
+ window refresh.
+
+
+.. method:: window.clear()
+
+ Like :meth:`erase`, but also causes the whole window to be repainted upon next
+ call to :meth:`refresh`.
+
+
+.. method:: window.clearok(yes)
+
+ If *yes* is 1, the next call to :meth:`refresh` will clear the window
+ completely.
+
+
+.. method:: window.clrtobot()
+
+ Erase from cursor to the end of the window: all lines below the cursor are
+ deleted, and then the equivalent of :meth:`clrtoeol` is performed.
+
+
+.. method:: window.clrtoeol()
+
+ Erase from cursor to the end of the line.
+
+
+.. method:: window.cursyncup()
+
+ Updates the current cursor position of all the ancestors of the window to
+ reflect the current cursor position of the window.
+
+
+.. method:: window.delch([y, x])
+
+ Delete any character at ``(y, x)``.
+
+
+.. method:: window.deleteln()
+
+ Delete the line under the cursor. All following lines are moved up by 1 line.
+
+
+.. method:: window.derwin([nlines, ncols,] begin_y, begin_x)
+
+ An abbreviation for "derive window", :meth:`derwin` is the same as calling
+ :meth:`subwin`, except that *begin_y* and *begin_x* are relative to the origin
+ of the window, rather than relative to the entire screen. Returns a window
+ object for the derived window.
+
+
+.. method:: window.echochar(ch[, attr])
+
+ Add character *ch* with attribute *attr*, and immediately call :meth:`refresh`
+ on the window.
+
+
+.. method:: window.enclose(y, x)
+
+ Tests whether the given pair of screen-relative character-cell coordinates are
+ enclosed by the given window, returning true or false. It is useful for
+ determining what subset of the screen windows enclose the location of a mouse
+ event.
+
+
+.. method:: window.erase()
+
+ Clear the window.
+
+
+.. method:: window.getbegyx()
+
+ Return a tuple ``(y, x)`` of co-ordinates of upper-left corner.
+
+
+.. method:: window.getch([y, x])
+
+ Get a character. Note that the integer returned does *not* have to be in ASCII
+ range: function keys, keypad keys and so on return numbers higher than 256. In
+ no-delay mode, -1 is returned if there is no input.
+
+
+.. method:: window.getkey([y, x])
+
+ Get a character, returning a string instead of an integer, as :meth:`getch`
+ does. Function keys, keypad keys and so on return a multibyte string containing
+ the key name. In no-delay mode, an exception is raised if there is no input.
+
+
+.. method:: window.getmaxyx()
+
+ Return a tuple ``(y, x)`` of the height and width of the window.
+
+
+.. method:: window.getparyx()
+
+ Returns the beginning coordinates of this window relative to its parent window
+ into two integer variables y and x. Returns ``-1,-1`` if this window has no
+ parent.
+
+
+.. method:: window.getstr([y, x])
+
+ Read a string from the user, with primitive line editing capacity.
+
+
+.. method:: window.getyx()
+
+ Return a tuple ``(y, x)`` of current cursor position relative to the window's
+ upper-left corner.
+
+
+.. method:: window.hline([y, x,] ch, n)
+
+ Display a horizontal line starting at ``(y, x)`` with length *n* consisting of
+ the character *ch*.
+
+
+.. method:: window.idcok(flag)
+
+ If *flag* is false, curses no longer considers using the hardware insert/delete
+ character feature of the terminal; if *flag* is true, use of character insertion
+ and deletion is enabled. When curses is first initialized, use of character
+ insert/delete is enabled by default.
+
+
+.. method:: window.idlok(yes)
+
+ If called with *yes* equal to 1, :mod:`curses` will try and use hardware line
+ editing facilities. Otherwise, line insertion/deletion are disabled.
+
+
+.. method:: window.immedok(flag)
+
+ If *flag* is true, any change in the window image automatically causes the
+ window to be refreshed; you no longer have to call :meth:`refresh` yourself.
+ However, it may degrade performance considerably, due to repeated calls to
+ wrefresh. This option is disabled by default.
+
+
+.. method:: window.inch([y, x])
+
+ Return the character at the given position in the window. The bottom 8 bits are
+ the character proper, and upper bits are the attributes.
+
+
+.. method:: window.insch([y, x,] ch[, attr])
+
+ Paint character *ch* at ``(y, x)`` with attributes *attr*, moving the line from
+ position *x* right by one character.
+
+
+.. method:: window.insdelln(nlines)
+
+ Inserts *nlines* lines into the specified window above the current line. The
+ *nlines* bottom lines are lost. For negative *nlines*, delete *nlines* lines
+ starting with the one under the cursor, and move the remaining lines up. The
+ bottom *nlines* lines are cleared. The current cursor position remains the
+ same.
+
+
+.. method:: window.insertln()
+
+ Insert a blank line under the cursor. All following lines are moved down by 1
+ line.
+
+
+.. method:: window.insnstr([y, x,] str, n [, attr])
+
+ Insert a character string (as many characters as will fit on the line) before
+ the character under the cursor, up to *n* characters. If *n* is zero or
+ negative, the entire string is inserted. All characters to the right of the
+ cursor are shifted right, with the rightmost characters on the line being lost.
+ The cursor position does not change (after moving to *y*, *x*, if specified).
+
+
+.. method:: window.insstr([y, x, ] str [, attr])
+
+ Insert a character string (as many characters as will fit on the line) before
+ the character under the cursor. All characters to the right of the cursor are
+ shifted right, with the rightmost characters on the line being lost. The cursor
+ position does not change (after moving to *y*, *x*, if specified).
+
+
+.. method:: window.instr([y, x] [, n])
+
+ Returns a string of characters, extracted from the window starting at the
+ current cursor position, or at *y*, *x* if specified. Attributes are stripped
+ from the characters. If *n* is specified, :meth:`instr` returns return a string
+ at most *n* characters long (exclusive of the trailing NUL).
+
+
+.. method:: window.is_linetouched(line)
+
+ Returns true if the specified line was modified since the last call to
+ :meth:`refresh`; otherwise returns false. Raises a :exc:`curses.error`
+ exception if *line* is not valid for the given window.
+
+
+.. method:: window.is_wintouched()
+
+ Returns true if the specified window was modified since the last call to
+ :meth:`refresh`; otherwise returns false.
+
+
+.. method:: window.keypad(yes)
+
+ If *yes* is 1, escape sequences generated by some keys (keypad, function keys)
+ will be interpreted by :mod:`curses`. If *yes* is 0, escape sequences will be
+ left as is in the input stream.
+
+
+.. method:: window.leaveok(yes)
+
+ If *yes* is 1, cursor is left where it is on update, instead of being at "cursor
+ position." This reduces cursor movement where possible. If possible the cursor
+ will be made invisible.
+
+ If *yes* is 0, cursor will always be at "cursor position" after an update.
+
+
+.. method:: window.move(new_y, new_x)
+
+ Move cursor to ``(new_y, new_x)``.
+
+
+.. method:: window.mvderwin(y, x)
+
+ Moves the window inside its parent window. The screen-relative parameters of
+ the window are not changed. This routine is used to display different parts of
+ the parent window at the same physical position on the screen.
+
+
+.. method:: window.mvwin(new_y, new_x)
+
+ Move the window so its upper-left corner is at ``(new_y, new_x)``.
+
+
+.. method:: window.nodelay(yes)
+
+ If *yes* is ``1``, :meth:`getch` will be non-blocking.
+
+
+.. method:: window.notimeout(yes)
+
+ If *yes* is ``1``, escape sequences will not be timed out.
+
+ If *yes* is ``0``, after a few milliseconds, an escape sequence will not be
+ interpreted, and will be left in the input stream as is.
+
+
+.. method:: window.noutrefresh()
+
+ Mark for refresh but wait. This function updates the data structure
+ representing the desired state of the window, but does not force an update of
+ the physical screen. To accomplish that, call :func:`doupdate`.
+
+
+.. method:: window.overlay(destwin[, sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol])
+
+ Overlay the window on top of *destwin*. The windows need not be the same size,
+ only the overlapping region is copied. This copy is non-destructive, which means
+ that the current background character does not overwrite the old contents of
+ *destwin*.
+
+ To get fine-grained control over the copied region, the second form of
+ :meth:`overlay` can be used. *sminrow* and *smincol* are the upper-left
+ coordinates of the source window, and the other variables mark a rectangle in
+ the destination window.
+
+
+.. method:: window.overwrite(destwin[, sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol])
+
+ Overwrite the window on top of *destwin*. The windows need not be the same size,
+ in which case only the overlapping region is copied. This copy is destructive,
+ which means that the current background character overwrites the old contents of
+ *destwin*.
+
+ To get fine-grained control over the copied region, the second form of
+ :meth:`overwrite` can be used. *sminrow* and *smincol* are the upper-left
+ coordinates of the source window, the other variables mark a rectangle in the
+ destination window.
+
+
+.. method:: window.putwin(file)
+
+ Writes all data associated with the window into the provided file object. This
+ information can be later retrieved using the :func:`getwin` function.
+
+
+.. method:: window.redrawln(beg, num)
+
+ Indicates that the *num* screen lines, starting at line *beg*, are corrupted and
+ should be completely redrawn on the next :meth:`refresh` call.
+
+
+.. method:: window.redrawwin()
+
+ Touches the entire window, causing it to be completely redrawn on the next
+ :meth:`refresh` call.
+
+
+.. method:: window.refresh([pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol])
+
+ Update the display immediately (sync actual screen with previous
+ drawing/deleting methods).
+
+ The 6 optional arguments can only be specified when the window is a pad created
+ with :func:`newpad`. The additional parameters are needed to indicate what part
+ of the pad and screen are involved. *pminrow* and *pmincol* specify the upper
+ left-hand corner of the rectangle to be displayed in the pad. *sminrow*,
+ *smincol*, *smaxrow*, and *smaxcol* specify the edges of the rectangle to be
+ displayed on the screen. The lower right-hand corner of the rectangle to be
+ displayed in the pad is calculated from the screen coordinates, since the
+ rectangles must be the same size. Both rectangles must be entirely contained
+ within their respective structures. Negative values of *pminrow*, *pmincol*,
+ *sminrow*, or *smincol* are treated as if they were zero.
+
+
+.. method:: window.scroll([lines=1])
+
+ Scroll the screen or scrolling region upward by *lines* lines.
+
+
+.. method:: window.scrollok(flag)
+
+ Controls what happens when the cursor of a window is moved off the edge of the
+ window or scrolling region, either as a result of a newline action on the bottom
+ line, or typing the last character of the last line. If *flag* is false, the
+ cursor is left on the bottom line. If *flag* is true, the window is scrolled up
+ one line. Note that in order to get the physical scrolling effect on the
+ terminal, it is also necessary to call :meth:`idlok`.
+
+
+.. method:: window.setscrreg(top, bottom)
+
+ Set the scrolling region from line *top* to line *bottom*. All scrolling actions
+ will take place in this region.
+
+
+.. method:: window.standend()
+
+ Turn off the standout attribute. On some terminals this has the side effect of
+ turning off all attributes.
+
+
+.. method:: window.standout()
+
+ Turn on attribute *A_STANDOUT*.
+
+
+.. method:: window.subpad([nlines, ncols,] begin_y, begin_x)
+
+ Return a sub-window, whose upper-left corner is at ``(begin_y, begin_x)``, and
+ whose width/height is *ncols*/*nlines*.
+
+
+.. method:: window.subwin([nlines, ncols,] begin_y, begin_x)
+
+ Return a sub-window, whose upper-left corner is at ``(begin_y, begin_x)``, and
+ whose width/height is *ncols*/*nlines*.
+
+ By default, the sub-window will extend from the specified position to the lower
+ right corner of the window.
+
+
+.. method:: window.syncdown()
+
+ Touches each location in the window that has been touched in any of its ancestor
+ windows. This routine is called by :meth:`refresh`, so it should almost never
+ be necessary to call it manually.
+
+
+.. method:: window.syncok(flag)
+
+ If called with *flag* set to true, then :meth:`syncup` is called automatically
+ whenever there is a change in the window.
+
+
+.. method:: window.syncup()
+
+ Touches all locations in ancestors of the window that have been changed in the
+ window.
+
+
+.. method:: window.timeout(delay)
+
+ Sets blocking or non-blocking read behavior for the window. If *delay* is
+ negative, blocking read is used (which will wait indefinitely for input). If
+ *delay* is zero, then non-blocking read is used, and -1 will be returned by
+ :meth:`getch` if no input is waiting. If *delay* is positive, then
+ :meth:`getch` will block for *delay* milliseconds, and return -1 if there is
+ still no input at the end of that time.
+
+
+.. method:: window.touchline(start, count[, changed])
+
+ Pretend *count* lines have been changed, starting with line *start*. If
+ *changed* is supplied, it specifies whether the affected lines are marked as
+ having been changed (*changed*\ =1) or unchanged (*changed*\ =0).
+
+
+.. method:: window.touchwin()
+
+ Pretend the whole window has been changed, for purposes of drawing
+ optimizations.
+
+
+.. method:: window.untouchwin()
+
+ Marks all lines in the window as unchanged since the last call to
+ :meth:`refresh`.
+
+
+.. method:: window.vline([y, x,] ch, n)
+
+ Display a vertical line starting at ``(y, x)`` with length *n* consisting of the
+ character *ch*.
+
+
+Constants
+---------
+
+The :mod:`curses` module defines the following data members:
+
+
+.. data:: ERR
+
+ Some curses routines that return an integer, such as :func:`getch`, return
+ :const:`ERR` upon failure.
+
+
+.. data:: OK
+
+ Some curses routines that return an integer, such as :func:`napms`, return
+ :const:`OK` upon success.
+
+
+.. data:: version
+
+ A string representing the current version of the module. Also available as
+ :const:`__version__`.
+
+Several constants are available to specify character cell attributes:
+
++------------------+-------------------------------+
+| Attribute | Meaning |
++==================+===============================+
+| ``A_ALTCHARSET`` | Alternate character set mode. |
++------------------+-------------------------------+
+| ``A_BLINK`` | Blink mode. |
++------------------+-------------------------------+
+| ``A_BOLD`` | Bold mode. |
++------------------+-------------------------------+
+| ``A_DIM`` | Dim mode. |
++------------------+-------------------------------+
+| ``A_NORMAL`` | Normal attribute. |
++------------------+-------------------------------+
+| ``A_STANDOUT`` | Standout mode. |
++------------------+-------------------------------+
+| ``A_UNDERLINE`` | Underline mode. |
++------------------+-------------------------------+
+
+Keys are referred to by integer constants with names starting with ``KEY_``.
+The exact keycaps available are system dependent.
+
+.. % XXX this table is far too large!
+.. % XXX should this table be alphabetized?
+
++-------------------+--------------------------------------------+
+| Key constant | Key |
++===================+============================================+
+| ``KEY_MIN`` | Minimum key value |
++-------------------+--------------------------------------------+
+| ``KEY_BREAK`` | Break key (unreliable) |
++-------------------+--------------------------------------------+
+| ``KEY_DOWN`` | Down-arrow |
++-------------------+--------------------------------------------+
+| ``KEY_UP`` | Up-arrow |
++-------------------+--------------------------------------------+
+| ``KEY_LEFT`` | Left-arrow |
++-------------------+--------------------------------------------+
+| ``KEY_RIGHT`` | Right-arrow |
++-------------------+--------------------------------------------+
+| ``KEY_HOME`` | Home key (upward+left arrow) |
++-------------------+--------------------------------------------+
+| ``KEY_BACKSPACE`` | Backspace (unreliable) |
++-------------------+--------------------------------------------+
+| ``KEY_F0`` | Function keys. Up to 64 function keys are |
+| | supported. |
++-------------------+--------------------------------------------+
+| ``KEY_Fn`` | Value of function key *n* |
++-------------------+--------------------------------------------+
+| ``KEY_DL`` | Delete line |
++-------------------+--------------------------------------------+
+| ``KEY_IL`` | Insert line |
++-------------------+--------------------------------------------+
+| ``KEY_DC`` | Delete character |
++-------------------+--------------------------------------------+
+| ``KEY_IC`` | Insert char or enter insert mode |
++-------------------+--------------------------------------------+
+| ``KEY_EIC`` | Exit insert char mode |
++-------------------+--------------------------------------------+
+| ``KEY_CLEAR`` | Clear screen |
++-------------------+--------------------------------------------+
+| ``KEY_EOS`` | Clear to end of screen |
++-------------------+--------------------------------------------+
+| ``KEY_EOL`` | Clear to end of line |
++-------------------+--------------------------------------------+
+| ``KEY_SF`` | Scroll 1 line forward |
++-------------------+--------------------------------------------+
+| ``KEY_SR`` | Scroll 1 line backward (reverse) |
++-------------------+--------------------------------------------+
+| ``KEY_NPAGE`` | Next page |
++-------------------+--------------------------------------------+
+| ``KEY_PPAGE`` | Previous page |
++-------------------+--------------------------------------------+
+| ``KEY_STAB`` | Set tab |
++-------------------+--------------------------------------------+
+| ``KEY_CTAB`` | Clear tab |
++-------------------+--------------------------------------------+
+| ``KEY_CATAB`` | Clear all tabs |
++-------------------+--------------------------------------------+
+| ``KEY_ENTER`` | Enter or send (unreliable) |
++-------------------+--------------------------------------------+
+| ``KEY_SRESET`` | Soft (partial) reset (unreliable) |
++-------------------+--------------------------------------------+
+| ``KEY_RESET`` | Reset or hard reset (unreliable) |
++-------------------+--------------------------------------------+
+| ``KEY_PRINT`` | Print |
++-------------------+--------------------------------------------+
+| ``KEY_LL`` | Home down or bottom (lower left) |
++-------------------+--------------------------------------------+
+| ``KEY_A1`` | Upper left of keypad |
++-------------------+--------------------------------------------+
+| ``KEY_A3`` | Upper right of keypad |
++-------------------+--------------------------------------------+
+| ``KEY_B2`` | Center of keypad |
++-------------------+--------------------------------------------+
+| ``KEY_C1`` | Lower left of keypad |
++-------------------+--------------------------------------------+
+| ``KEY_C3`` | Lower right of keypad |
++-------------------+--------------------------------------------+
+| ``KEY_BTAB`` | Back tab |
++-------------------+--------------------------------------------+
+| ``KEY_BEG`` | Beg (beginning) |
++-------------------+--------------------------------------------+
+| ``KEY_CANCEL`` | Cancel |
++-------------------+--------------------------------------------+
+| ``KEY_CLOSE`` | Close |
++-------------------+--------------------------------------------+
+| ``KEY_COMMAND`` | Cmd (command) |
++-------------------+--------------------------------------------+
+| ``KEY_COPY`` | Copy |
++-------------------+--------------------------------------------+
+| ``KEY_CREATE`` | Create |
++-------------------+--------------------------------------------+
+| ``KEY_END`` | End |
++-------------------+--------------------------------------------+
+| ``KEY_EXIT`` | Exit |
++-------------------+--------------------------------------------+
+| ``KEY_FIND`` | Find |
++-------------------+--------------------------------------------+
+| ``KEY_HELP`` | Help |
++-------------------+--------------------------------------------+
+| ``KEY_MARK`` | Mark |
++-------------------+--------------------------------------------+
+| ``KEY_MESSAGE`` | Message |
++-------------------+--------------------------------------------+
+| ``KEY_MOVE`` | Move |
++-------------------+--------------------------------------------+
+| ``KEY_NEXT`` | Next |
++-------------------+--------------------------------------------+
+| ``KEY_OPEN`` | Open |
++-------------------+--------------------------------------------+
+| ``KEY_OPTIONS`` | Options |
++-------------------+--------------------------------------------+
+| ``KEY_PREVIOUS`` | Prev (previous) |
++-------------------+--------------------------------------------+
+| ``KEY_REDO`` | Redo |
++-------------------+--------------------------------------------+
+| ``KEY_REFERENCE`` | Ref (reference) |
++-------------------+--------------------------------------------+
+| ``KEY_REFRESH`` | Refresh |
++-------------------+--------------------------------------------+
+| ``KEY_REPLACE`` | Replace |
++-------------------+--------------------------------------------+
+| ``KEY_RESTART`` | Restart |
++-------------------+--------------------------------------------+
+| ``KEY_RESUME`` | Resume |
++-------------------+--------------------------------------------+
+| ``KEY_SAVE`` | Save |
++-------------------+--------------------------------------------+
+| ``KEY_SBEG`` | Shifted Beg (beginning) |
++-------------------+--------------------------------------------+
+| ``KEY_SCANCEL`` | Shifted Cancel |
++-------------------+--------------------------------------------+
+| ``KEY_SCOMMAND`` | Shifted Command |
++-------------------+--------------------------------------------+
+| ``KEY_SCOPY`` | Shifted Copy |
++-------------------+--------------------------------------------+
+| ``KEY_SCREATE`` | Shifted Create |
++-------------------+--------------------------------------------+
+| ``KEY_SDC`` | Shifted Delete char |
++-------------------+--------------------------------------------+
+| ``KEY_SDL`` | Shifted Delete line |
++-------------------+--------------------------------------------+
+| ``KEY_SELECT`` | Select |
++-------------------+--------------------------------------------+
+| ``KEY_SEND`` | Shifted End |
++-------------------+--------------------------------------------+
+| ``KEY_SEOL`` | Shifted Clear line |
++-------------------+--------------------------------------------+
+| ``KEY_SEXIT`` | Shifted Dxit |
++-------------------+--------------------------------------------+
+| ``KEY_SFIND`` | Shifted Find |
++-------------------+--------------------------------------------+
+| ``KEY_SHELP`` | Shifted Help |
++-------------------+--------------------------------------------+
+| ``KEY_SHOME`` | Shifted Home |
++-------------------+--------------------------------------------+
+| ``KEY_SIC`` | Shifted Input |
++-------------------+--------------------------------------------+
+| ``KEY_SLEFT`` | Shifted Left arrow |
++-------------------+--------------------------------------------+
+| ``KEY_SMESSAGE`` | Shifted Message |
++-------------------+--------------------------------------------+
+| ``KEY_SMOVE`` | Shifted Move |
++-------------------+--------------------------------------------+
+| ``KEY_SNEXT`` | Shifted Next |
++-------------------+--------------------------------------------+
+| ``KEY_SOPTIONS`` | Shifted Options |
++-------------------+--------------------------------------------+
+| ``KEY_SPREVIOUS`` | Shifted Prev |
++-------------------+--------------------------------------------+
+| ``KEY_SPRINT`` | Shifted Print |
++-------------------+--------------------------------------------+
+| ``KEY_SREDO`` | Shifted Redo |
++-------------------+--------------------------------------------+
+| ``KEY_SREPLACE`` | Shifted Replace |
++-------------------+--------------------------------------------+
+| ``KEY_SRIGHT`` | Shifted Right arrow |
++-------------------+--------------------------------------------+
+| ``KEY_SRSUME`` | Shifted Resume |
++-------------------+--------------------------------------------+
+| ``KEY_SSAVE`` | Shifted Save |
++-------------------+--------------------------------------------+
+| ``KEY_SSUSPEND`` | Shifted Suspend |
++-------------------+--------------------------------------------+
+| ``KEY_SUNDO`` | Shifted Undo |
++-------------------+--------------------------------------------+
+| ``KEY_SUSPEND`` | Suspend |
++-------------------+--------------------------------------------+
+| ``KEY_UNDO`` | Undo |
++-------------------+--------------------------------------------+
+| ``KEY_MOUSE`` | Mouse event has occurred |
++-------------------+--------------------------------------------+
+| ``KEY_RESIZE`` | Terminal resize event |
++-------------------+--------------------------------------------+
+| ``KEY_MAX`` | Maximum key value |
++-------------------+--------------------------------------------+
+
+On VT100s and their software emulations, such as X terminal emulators, there are
+normally at least four function keys (:const:`KEY_F1`, :const:`KEY_F2`,
+:const:`KEY_F3`, :const:`KEY_F4`) available, and the arrow keys mapped to
+:const:`KEY_UP`, :const:`KEY_DOWN`, :const:`KEY_LEFT` and :const:`KEY_RIGHT` in
+the obvious way. If your machine has a PC keyboard, it is safe to expect arrow
+keys and twelve function keys (older PC keyboards may have only ten function
+keys); also, the following keypad mappings are standard:
+
++------------------+-----------+
+| Keycap | Constant |
++==================+===========+
+| :kbd:`Insert` | KEY_IC |
++------------------+-----------+
+| :kbd:`Delete` | KEY_DC |
++------------------+-----------+
+| :kbd:`Home` | KEY_HOME |
++------------------+-----------+
+| :kbd:`End` | KEY_END |
++------------------+-----------+
+| :kbd:`Page Up` | KEY_NPAGE |
++------------------+-----------+
+| :kbd:`Page Down` | KEY_PPAGE |
++------------------+-----------+
+
+The following table lists characters from the alternate character set. These are
+inherited from the VT100 terminal, and will generally be available on software
+emulations such as X terminals. When there is no graphic available, curses
+falls back on a crude printable ASCII approximation.
+
+.. note::
+
+ These are available only after :func:`initscr` has been called.
+
++------------------+------------------------------------------+
+| ACS code | Meaning |
++==================+==========================================+
+| ``ACS_BBSS`` | alternate name for upper right corner |
++------------------+------------------------------------------+
+| ``ACS_BLOCK`` | solid square block |
++------------------+------------------------------------------+
+| ``ACS_BOARD`` | board of squares |
++------------------+------------------------------------------+
+| ``ACS_BSBS`` | alternate name for horizontal line |
++------------------+------------------------------------------+
+| ``ACS_BSSB`` | alternate name for upper left corner |
++------------------+------------------------------------------+
+| ``ACS_BSSS`` | alternate name for top tee |
++------------------+------------------------------------------+
+| ``ACS_BTEE`` | bottom tee |
++------------------+------------------------------------------+
+| ``ACS_BULLET`` | bullet |
++------------------+------------------------------------------+
+| ``ACS_CKBOARD`` | checker board (stipple) |
++------------------+------------------------------------------+
+| ``ACS_DARROW`` | arrow pointing down |
++------------------+------------------------------------------+
+| ``ACS_DEGREE`` | degree symbol |
++------------------+------------------------------------------+
+| ``ACS_DIAMOND`` | diamond |
++------------------+------------------------------------------+
+| ``ACS_GEQUAL`` | greater-than-or-equal-to |
++------------------+------------------------------------------+
+| ``ACS_HLINE`` | horizontal line |
++------------------+------------------------------------------+
+| ``ACS_LANTERN`` | lantern symbol |
++------------------+------------------------------------------+
+| ``ACS_LARROW`` | left arrow |
++------------------+------------------------------------------+
+| ``ACS_LEQUAL`` | less-than-or-equal-to |
++------------------+------------------------------------------+
+| ``ACS_LLCORNER`` | lower left-hand corner |
++------------------+------------------------------------------+
+| ``ACS_LRCORNER`` | lower right-hand corner |
++------------------+------------------------------------------+
+| ``ACS_LTEE`` | left tee |
++------------------+------------------------------------------+
+| ``ACS_NEQUAL`` | not-equal sign |
++------------------+------------------------------------------+
+| ``ACS_PI`` | letter pi |
++------------------+------------------------------------------+
+| ``ACS_PLMINUS`` | plus-or-minus sign |
++------------------+------------------------------------------+
+| ``ACS_PLUS`` | big plus sign |
++------------------+------------------------------------------+
+| ``ACS_RARROW`` | right arrow |
++------------------+------------------------------------------+
+| ``ACS_RTEE`` | right tee |
++------------------+------------------------------------------+
+| ``ACS_S1`` | scan line 1 |
++------------------+------------------------------------------+
+| ``ACS_S3`` | scan line 3 |
++------------------+------------------------------------------+
+| ``ACS_S7`` | scan line 7 |
++------------------+------------------------------------------+
+| ``ACS_S9`` | scan line 9 |
++------------------+------------------------------------------+
+| ``ACS_SBBS`` | alternate name for lower right corner |
++------------------+------------------------------------------+
+| ``ACS_SBSB`` | alternate name for vertical line |
++------------------+------------------------------------------+
+| ``ACS_SBSS`` | alternate name for right tee |
++------------------+------------------------------------------+
+| ``ACS_SSBB`` | alternate name for lower left corner |
++------------------+------------------------------------------+
+| ``ACS_SSBS`` | alternate name for bottom tee |
++------------------+------------------------------------------+
+| ``ACS_SSSB`` | alternate name for left tee |
++------------------+------------------------------------------+
+| ``ACS_SSSS`` | alternate name for crossover or big plus |
++------------------+------------------------------------------+
+| ``ACS_STERLING`` | pound sterling |
++------------------+------------------------------------------+
+| ``ACS_TTEE`` | top tee |
++------------------+------------------------------------------+
+| ``ACS_UARROW`` | up arrow |
++------------------+------------------------------------------+
+| ``ACS_ULCORNER`` | upper left corner |
++------------------+------------------------------------------+
+| ``ACS_URCORNER`` | upper right corner |
++------------------+------------------------------------------+
+| ``ACS_VLINE`` | vertical line |
++------------------+------------------------------------------+
+
+The following table lists the predefined colors:
+
++-------------------+----------------------------+
+| Constant | Color |
++===================+============================+
+| ``COLOR_BLACK`` | Black |
++-------------------+----------------------------+
+| ``COLOR_BLUE`` | Blue |
++-------------------+----------------------------+
+| ``COLOR_CYAN`` | Cyan (light greenish blue) |
++-------------------+----------------------------+
+| ``COLOR_GREEN`` | Green |
++-------------------+----------------------------+
+| ``COLOR_MAGENTA`` | Magenta (purplish red) |
++-------------------+----------------------------+
+| ``COLOR_RED`` | Red |
++-------------------+----------------------------+
+| ``COLOR_WHITE`` | White |
++-------------------+----------------------------+
+| ``COLOR_YELLOW`` | Yellow |
++-------------------+----------------------------+
+
+
+:mod:`curses.textpad` --- Text input widget for curses programs
+===============================================================
+
+.. module:: curses.textpad
+ :synopsis: Emacs-like input editing in a curses window.
+.. moduleauthor:: Eric Raymond <esr@thyrsus.com>
+.. sectionauthor:: Eric Raymond <esr@thyrsus.com>
+
+
+.. versionadded:: 1.6
+
+The :mod:`curses.textpad` module provides a :class:`Textbox` class that handles
+elementary text editing in a curses window, supporting a set of keybindings
+resembling those of Emacs (thus, also of Netscape Navigator, BBedit 6.x,
+FrameMaker, and many other programs). The module also provides a
+rectangle-drawing function useful for framing text boxes or for other purposes.
+
+The module :mod:`curses.textpad` defines the following function:
+
+
+.. function:: rectangle(win, uly, ulx, lry, lrx)
+
+ Draw a rectangle. The first argument must be a window object; the remaining
+ arguments are coordinates relative to that window. The second and third
+ arguments are the y and x coordinates of the upper left hand corner of the
+ rectangle to be drawn; the fourth and fifth arguments are the y and x
+ coordinates of the lower right hand corner. The rectangle will be drawn using
+ VT100/IBM PC forms characters on terminals that make this possible (including
+ xterm and most other software terminal emulators). Otherwise it will be drawn
+ with ASCII dashes, vertical bars, and plus signs.
+
+
+.. _curses-textpad-objects:
+
+Textbox objects
+---------------
+
+You can instantiate a :class:`Textbox` object as follows:
+
+
+.. class:: Textbox(win)
+
+ Return a textbox widget object. The *win* argument should be a curses
+ :class:`WindowObject` in which the textbox is to be contained. The edit cursor
+ of the textbox is initially located at the upper left hand corner of the
+ containing window, with coordinates ``(0, 0)``. The instance's
+ :attr:`stripspaces` flag is initially on.
+
+:class:`Textbox` objects have the following methods:
+
+
+.. method:: Textbox.edit([validator])
+
+ This is the entry point you will normally use. It accepts editing keystrokes
+ until one of the termination keystrokes is entered. If *validator* is supplied,
+ it must be a function. It will be called for each keystroke entered with the
+ keystroke as a parameter; command dispatch is done on the result. This method
+ returns the window contents as a string; whether blanks in the window are
+ included is affected by the :attr:`stripspaces` member.
+
+
+.. method:: Textbox.do_command(ch)
+
+ Process a single command keystroke. Here are the supported special keystrokes:
+
+ +------------------+-------------------------------------------+
+ | Keystroke | Action |
+ +==================+===========================================+
+ | :kbd:`Control-A` | Go to left edge of window. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-B` | Cursor left, wrapping to previous line if |
+ | | appropriate. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-D` | Delete character under cursor. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-E` | Go to right edge (stripspaces off) or end |
+ | | of line (stripspaces on). |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-F` | Cursor right, wrapping to next line when |
+ | | appropriate. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-G` | Terminate, returning the window contents. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-H` | Delete character backward. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-J` | Terminate if the window is 1 line, |
+ | | otherwise insert newline. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-K` | If line is blank, delete it, otherwise |
+ | | clear to end of line. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-L` | Refresh screen. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-N` | Cursor down; move down one line. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-O` | Insert a blank line at cursor location. |
+ +------------------+-------------------------------------------+
+ | :kbd:`Control-P` | Cursor up; move up one line. |
+ +------------------+-------------------------------------------+
+
+ Move operations do nothing if the cursor is at an edge where the movement is not
+ possible. The following synonyms are supported where possible:
+
+ +------------------------+------------------+
+ | Constant | Keystroke |
+ +========================+==================+
+ | :const:`KEY_LEFT` | :kbd:`Control-B` |
+ +------------------------+------------------+
+ | :const:`KEY_RIGHT` | :kbd:`Control-F` |
+ +------------------------+------------------+
+ | :const:`KEY_UP` | :kbd:`Control-P` |
+ +------------------------+------------------+
+ | :const:`KEY_DOWN` | :kbd:`Control-N` |
+ +------------------------+------------------+
+ | :const:`KEY_BACKSPACE` | :kbd:`Control-h` |
+ +------------------------+------------------+
+
+ All other keystrokes are treated as a command to insert the given character and
+ move right (with line wrapping).
+
+
+.. method:: Textbox.gather()
+
+ This method returns the window contents as a string; whether blanks in the
+ window are included is affected by the :attr:`stripspaces` member.
+
+
+.. attribute:: Textbox.stripspaces
+
+ This data member is a flag which controls the interpretation of blanks in the
+ window. When it is on, trailing blanks on each line are ignored; any cursor
+ motion that would land the cursor on a trailing blank goes to the end of that
+ line instead, and trailing blanks are stripped when the window contents are
+ gathered.
+
+
+:mod:`curses.wrapper` --- Terminal handler for curses programs
+==============================================================
+
+.. module:: curses.wrapper
+ :synopsis: Terminal configuration wrapper for curses programs.
+.. moduleauthor:: Eric Raymond <esr@thyrsus.com>
+.. sectionauthor:: Eric Raymond <esr@thyrsus.com>
+
+
+.. versionadded:: 1.6
+
+This module supplies one function, :func:`wrapper`, which runs another function
+which should be the rest of your curses-using application. If the application
+raises an exception, :func:`wrapper` will restore the terminal to a sane state
+before re-raising the exception and generating a traceback.
+
+
+.. function:: wrapper(func, ...)
+
+ Wrapper function that initializes curses and calls another function, *func*,
+ restoring normal keyboard/screen behavior on error. The callable object *func*
+ is then passed the main window 'stdscr' as its first argument, followed by any
+ other arguments passed to :func:`wrapper`.
+
+Before calling the hook function, :func:`wrapper` turns on cbreak mode, turns
+off echo, enables the terminal keypad, and initializes colors if the terminal
+has color support. On exit (whether normally or by exception) it restores
+cooked mode, turns on echo, and disables the terminal keypad.
+
diff --git a/Doc/library/custominterp.rst b/Doc/library/custominterp.rst
new file mode 100644
index 0000000000..2a9f0a4480
--- /dev/null
+++ b/Doc/library/custominterp.rst
@@ -0,0 +1,20 @@
+
+.. _custominterp:
+
+**************************
+Custom Python Interpreters
+**************************
+
+The modules described in this chapter allow writing interfaces similar to
+Python's interactive interpreter. If you want a Python interpreter that
+supports some special feature in addition to the Python language, you should
+look at the :mod:`code` module. (The :mod:`codeop` module is lower-level, used
+to support compiling a possibly-incomplete chunk of Python code.)
+
+The full list of modules described in this chapter is:
+
+
+.. toctree::
+
+ code.rst
+ codeop.rst
diff --git a/Doc/library/datatypes.rst b/Doc/library/datatypes.rst
new file mode 100644
index 0000000000..4cd042d503
--- /dev/null
+++ b/Doc/library/datatypes.rst
@@ -0,0 +1,37 @@
+
+.. _datatypes:
+
+**********
+Data Types
+**********
+
+The modules described in this chapter provide a variety of specialized data
+types such as dates and times, fixed-type arrays, heap queues, synchronized
+queues, and sets.
+
+Python also provides some built-in data types, in particular,
+:class:`dict`, :class:`list`, :class:`set` and :class:`frozenset`, and
+:class:`tuple`. The :class:`str` class can be used to handle binary data
+and 8-bit text, and the :class:`unicode` class to handle Unicode text.
+
+The following modules are documented in this chapter:
+
+
+.. toctree::
+
+ datetime.rst
+ calendar.rst
+ collections.rst
+ heapq.rst
+ bisect.rst
+ array.rst
+ sched.rst
+ mutex.rst
+ queue.rst
+ weakref.rst
+ userdict.rst
+ types.rst
+ new.rst
+ copy.rst
+ pprint.rst
+ repr.rst
diff --git a/Doc/library/datetime.rst b/Doc/library/datetime.rst
new file mode 100644
index 0000000000..24d4f69dfe
--- /dev/null
+++ b/Doc/library/datetime.rst
@@ -0,0 +1,1348 @@
+.. % XXX what order should the types be discussed in?
+
+
+:mod:`datetime` --- Basic date and time types
+=============================================
+
+.. module:: datetime
+ :synopsis: Basic date and time types.
+.. moduleauthor:: Tim Peters <tim@zope.com>
+.. sectionauthor:: Tim Peters <tim@zope.com>
+.. sectionauthor:: A.M. Kuchling <amk@amk.ca>
+
+
+.. versionadded:: 2.3
+
+The :mod:`datetime` module supplies classes for manipulating dates and times in
+both simple and complex ways. While date and time arithmetic is supported, the
+focus of the implementation is on efficient member extraction for output
+formatting and manipulation. For related
+functionality, see also the :mod:`time` and :mod:`calendar` modules.
+
+There are two kinds of date and time objects: "naive" and "aware". This
+distinction refers to whether the object has any notion of time zone, daylight
+saving time, or other kind of algorithmic or political time adjustment. Whether
+a naive :class:`datetime` object represents Coordinated Universal Time (UTC),
+local time, or time in some other timezone is purely up to the program, just
+like it's up to the program whether a particular number represents metres,
+miles, or mass. Naive :class:`datetime` objects are easy to understand and to
+work with, at the cost of ignoring some aspects of reality.
+
+For applications requiring more, :class:`datetime` and :class:`time` objects
+have an optional time zone information member, :attr:`tzinfo`, that can contain
+an instance of a subclass of the abstract :class:`tzinfo` class. These
+:class:`tzinfo` objects capture information about the offset from UTC time, the
+time zone name, and whether Daylight Saving Time is in effect. Note that no
+concrete :class:`tzinfo` classes are supplied by the :mod:`datetime` module.
+Supporting timezones at whatever level of detail is required is up to the
+application. The rules for time adjustment across the world are more political
+than rational, and there is no standard suitable for every application.
+
+The :mod:`datetime` module exports the following constants:
+
+
+.. data:: MINYEAR
+
+ The smallest year number allowed in a :class:`date` or :class:`datetime` object.
+ :const:`MINYEAR` is ``1``.
+
+
+.. data:: MAXYEAR
+
+ The largest year number allowed in a :class:`date` or :class:`datetime` object.
+ :const:`MAXYEAR` is ``9999``.
+
+
+.. seealso::
+
+ Module :mod:`calendar`
+ General calendar related functions.
+
+ Module :mod:`time`
+ Time access and conversions.
+
+
+Available Types
+---------------
+
+
+.. class:: date
+
+ An idealized naive date, assuming the current Gregorian calendar always was, and
+ always will be, in effect. Attributes: :attr:`year`, :attr:`month`, and
+ :attr:`day`.
+
+
+.. class:: time
+
+ An idealized time, independent of any particular day, assuming that every day
+ has exactly 24\*60\*60 seconds (there is no notion of "leap seconds" here).
+ Attributes: :attr:`hour`, :attr:`minute`, :attr:`second`, :attr:`microsecond`,
+ and :attr:`tzinfo`.
+
+
+.. class:: datetime
+
+ A combination of a date and a time. Attributes: :attr:`year`, :attr:`month`,
+ :attr:`day`, :attr:`hour`, :attr:`minute`, :attr:`second`, :attr:`microsecond`,
+ and :attr:`tzinfo`.
+
+
+.. class:: timedelta
+
+ A duration expressing the difference between two :class:`date`, :class:`time`,
+ or :class:`datetime` instances to microsecond resolution.
+
+
+.. class:: tzinfo
+
+ An abstract base class for time zone information objects. These are used by the
+ :class:`datetime` and :class:`time` classes to provide a customizable notion of
+ time adjustment (for example, to account for time zone and/or daylight saving
+ time).
+
+Objects of these types are immutable.
+
+Objects of the :class:`date` type are always naive.
+
+An object *d* of type :class:`time` or :class:`datetime` may be naive or aware.
+*d* is aware if ``d.tzinfo`` is not ``None`` and ``d.tzinfo.utcoffset(d)`` does
+not return ``None``. If ``d.tzinfo`` is ``None``, or if ``d.tzinfo`` is not
+``None`` but ``d.tzinfo.utcoffset(d)`` returns ``None``, *d* is naive.
+
+The distinction between naive and aware doesn't apply to :class:`timedelta`
+objects.
+
+Subclass relationships::
+
+ object
+ timedelta
+ tzinfo
+ time
+ date
+ datetime
+
+
+.. _datetime-timedelta:
+
+:class:`timedelta` Objects
+--------------------------
+
+A :class:`timedelta` object represents a duration, the difference between two
+dates or times.
+
+
+.. class:: timedelta([days[, seconds[, microseconds[, milliseconds[, minutes[, hours[, weeks]]]]]]])
+
+ All arguments are optional and default to ``0``. Arguments may be ints, longs,
+ or floats, and may be positive or negative.
+
+ Only *days*, *seconds* and *microseconds* are stored internally. Arguments are
+ converted to those units:
+
+ * A millisecond is converted to 1000 microseconds.
+ * A minute is converted to 60 seconds.
+ * An hour is converted to 3600 seconds.
+ * A week is converted to 7 days.
+
+ and days, seconds and microseconds are then normalized so that the
+ representation is unique, with
+
+ * ``0 <= microseconds < 1000000``
+ * ``0 <= seconds < 3600*24`` (the number of seconds in one day)
+ * ``-999999999 <= days <= 999999999``
+
+ If any argument is a float and there are fractional microseconds, the fractional
+ microseconds left over from all arguments are combined and their sum is rounded
+ to the nearest microsecond. If no argument is a float, the conversion and
+ normalization processes are exact (no information is lost).
+
+ If the normalized value of days lies outside the indicated range,
+ :exc:`OverflowError` is raised.
+
+ Note that normalization of negative values may be surprising at first. For
+ example, ::
+
+ >>> d = timedelta(microseconds=-1)
+ >>> (d.days, d.seconds, d.microseconds)
+ (-1, 86399, 999999)
+
+Class attributes are:
+
+
+.. attribute:: timedelta.min
+
+ The most negative :class:`timedelta` object, ``timedelta(-999999999)``.
+
+
+.. attribute:: timedelta.max
+
+ The most positive :class:`timedelta` object, ``timedelta(days=999999999,
+ hours=23, minutes=59, seconds=59, microseconds=999999)``.
+
+
+.. attribute:: timedelta.resolution
+
+ The smallest possible difference between non-equal :class:`timedelta` objects,
+ ``timedelta(microseconds=1)``.
+
+Note that, because of normalization, ``timedelta.max`` > ``-timedelta.min``.
+``-timedelta.max`` is not representable as a :class:`timedelta` object.
+
+Instance attributes (read-only):
+
++------------------+--------------------------------------------+
+| Attribute | Value |
++==================+============================================+
+| ``days`` | Between -999999999 and 999999999 inclusive |
++------------------+--------------------------------------------+
+| ``seconds`` | Between 0 and 86399 inclusive |
++------------------+--------------------------------------------+
+| ``microseconds`` | Between 0 and 999999 inclusive |
++------------------+--------------------------------------------+
+
+Supported operations:
+
+.. % XXX this table is too wide!
+
++--------------------------------+-----------------------------------------------+
+| Operation | Result |
++================================+===============================================+
+| ``t1 = t2 + t3`` | Sum of *t2* and *t3*. Afterwards *t1*-*t2* == |
+| | *t3* and *t1*-*t3* == *t2* are true. (1) |
++--------------------------------+-----------------------------------------------+
+| ``t1 = t2 - t3`` | Difference of *t2* and *t3*. Afterwards *t1* |
+| | == *t2* - *t3* and *t2* == *t1* + *t3* are |
+| | true. (1) |
++--------------------------------+-----------------------------------------------+
+| ``t1 = t2 * i or t1 = i * t2`` | Delta multiplied by an integer or long. |
+| | Afterwards *t1* // i == *t2* is true, |
+| | provided ``i != 0``. |
++--------------------------------+-----------------------------------------------+
+| | In general, *t1* \* i == *t1* \* (i-1) + *t1* |
+| | is true. (1) |
++--------------------------------+-----------------------------------------------+
+| ``t1 = t2 // i`` | The floor is computed and the remainder (if |
+| | any) is thrown away. (3) |
++--------------------------------+-----------------------------------------------+
+| ``+t1`` | Returns a :class:`timedelta` object with the |
+| | same value. (2) |
++--------------------------------+-----------------------------------------------+
+| ``-t1`` | equivalent to :class:`timedelta`\ |
+| | (-*t1.days*, -*t1.seconds*, |
+| | -*t1.microseconds*), and to *t1*\* -1. (1)(4) |
++--------------------------------+-----------------------------------------------+
+| ``abs(t)`` | equivalent to +*t* when ``t.days >= 0``, and |
+| | to -*t* when ``t.days < 0``. (2) |
++--------------------------------+-----------------------------------------------+
+
+Notes:
+
+(1)
+ This is exact, but may overflow.
+
+(2)
+ This is exact, and cannot overflow.
+
+(3)
+ Division by 0 raises :exc:`ZeroDivisionError`.
+
+(4)
+ -*timedelta.max* is not representable as a :class:`timedelta` object.
+
+In addition to the operations listed above :class:`timedelta` objects support
+certain additions and subtractions with :class:`date` and :class:`datetime`
+objects (see below).
+
+Comparisons of :class:`timedelta` objects are supported with the
+:class:`timedelta` object representing the smaller duration considered to be the
+smaller timedelta. In order to stop mixed-type comparisons from falling back to
+the default comparison by object address, when a :class:`timedelta` object is
+compared to an object of a different type, :exc:`TypeError` is raised unless the
+comparison is ``==`` or ``!=``. The latter cases return :const:`False` or
+:const:`True`, respectively.
+
+:class:`timedelta` objects are hashable (usable as dictionary keys), support
+efficient pickling, and in Boolean contexts, a :class:`timedelta` object is
+considered to be true if and only if it isn't equal to ``timedelta(0)``.
+
+
+.. _datetime-date:
+
+:class:`date` Objects
+---------------------
+
+A :class:`date` object represents a date (year, month and day) in an idealized
+calendar, the current Gregorian calendar indefinitely extended in both
+directions. January 1 of year 1 is called day number 1, January 2 of year 1 is
+called day number 2, and so on. This matches the definition of the "proleptic
+Gregorian" calendar in Dershowitz and Reingold's book Calendrical Calculations,
+where it's the base calendar for all computations. See the book for algorithms
+for converting between proleptic Gregorian ordinals and many other calendar
+systems.
+
+
+.. class:: date(year, month, day)
+
+ All arguments are required. Arguments may be ints or longs, in the following
+ ranges:
+
+ * ``MINYEAR <= year <= MAXYEAR``
+ * ``1 <= month <= 12``
+ * ``1 <= day <= number of days in the given month and year``
+
+ If an argument outside those ranges is given, :exc:`ValueError` is raised.
+
+Other constructors, all class methods:
+
+
+.. method:: date.today()
+
+ Return the current local date. This is equivalent to
+ ``date.fromtimestamp(time.time())``.
+
+
+.. method:: date.fromtimestamp(timestamp)
+
+ Return the local date corresponding to the POSIX timestamp, such as is returned
+ by :func:`time.time`. This may raise :exc:`ValueError`, if the timestamp is out
+ of the range of values supported by the platform C :cfunc:`localtime` function.
+ It's common for this to be restricted to years from 1970 through 2038. Note
+ that on non-POSIX systems that include leap seconds in their notion of a
+ timestamp, leap seconds are ignored by :meth:`fromtimestamp`.
+
+
+.. method:: date.fromordinal(ordinal)
+
+ Return the date corresponding to the proleptic Gregorian ordinal, where January
+ 1 of year 1 has ordinal 1. :exc:`ValueError` is raised unless ``1 <= ordinal <=
+ date.max.toordinal()``. For any date *d*, ``date.fromordinal(d.toordinal()) ==
+ d``.
+
+Class attributes:
+
+
+.. attribute:: date.min
+
+ The earliest representable date, ``date(MINYEAR, 1, 1)``.
+
+
+.. attribute:: date.max
+
+ The latest representable date, ``date(MAXYEAR, 12, 31)``.
+
+
+.. attribute:: date.resolution
+
+ The smallest possible difference between non-equal date objects,
+ ``timedelta(days=1)``.
+
+Instance attributes (read-only):
+
+
+.. attribute:: date.year
+
+ Between :const:`MINYEAR` and :const:`MAXYEAR` inclusive.
+
+
+.. attribute:: date.month
+
+ Between 1 and 12 inclusive.
+
+
+.. attribute:: date.day
+
+ Between 1 and the number of days in the given month of the given year.
+
+Supported operations:
+
++-------------------------------+----------------------------------------------+
+| Operation | Result |
++===============================+==============================================+
+| ``date2 = date1 + timedelta`` | *date2* is ``timedelta.days`` days removed |
+| | from *date1*. (1) |
++-------------------------------+----------------------------------------------+
+| ``date2 = date1 - timedelta`` | Computes *date2* such that ``date2 + |
+| | timedelta == date1``. (2) |
++-------------------------------+----------------------------------------------+
+| ``timedelta = date1 - date2`` | \(3) |
++-------------------------------+----------------------------------------------+
+| ``date1 < date2`` | *date1* is considered less than *date2* when |
+| | *date1* precedes *date2* in time. (4) |
++-------------------------------+----------------------------------------------+
+
+Notes:
+
+(1)
+ *date2* is moved forward in time if ``timedelta.days > 0``, or backward if
+ ``timedelta.days < 0``. Afterward ``date2 - date1 == timedelta.days``.
+ ``timedelta.seconds`` and ``timedelta.microseconds`` are ignored.
+ :exc:`OverflowError` is raised if ``date2.year`` would be smaller than
+ :const:`MINYEAR` or larger than :const:`MAXYEAR`.
+
+(2)
+ This isn't quite equivalent to date1 + (-timedelta), because -timedelta in
+ isolation can overflow in cases where date1 - timedelta does not.
+ ``timedelta.seconds`` and ``timedelta.microseconds`` are ignored.
+
+(3)
+ This is exact, and cannot overflow. timedelta.seconds and
+ timedelta.microseconds are 0, and date2 + timedelta == date1 after.
+
+(4)
+ In other words, ``date1 < date2`` if and only if ``date1.toordinal() <
+ date2.toordinal()``. In order to stop comparison from falling back to the
+ default scheme of comparing object addresses, date comparison normally raises
+ :exc:`TypeError` if the other comparand isn't also a :class:`date` object.
+ However, ``NotImplemented`` is returned instead if the other comparand has a
+ :meth:`timetuple` attribute. This hook gives other kinds of date objects a
+ chance at implementing mixed-type comparison. If not, when a :class:`date`
+ object is compared to an object of a different type, :exc:`TypeError` is raised
+ unless the comparison is ``==`` or ``!=``. The latter cases return
+ :const:`False` or :const:`True`, respectively.
+
+Dates can be used as dictionary keys. In Boolean contexts, all :class:`date`
+objects are considered to be true.
+
+Instance methods:
+
+
+.. method:: date.replace(year, month, day)
+
+ Return a date with the same value, except for those members given new values by
+ whichever keyword arguments are specified. For example, if ``d == date(2002,
+ 12, 31)``, then ``d.replace(day=26) == date(2002, 12, 26)``.
+
+
+.. method:: date.timetuple()
+
+ Return a :class:`time.struct_time` such as returned by :func:`time.localtime`.
+ The hours, minutes and seconds are 0, and the DST flag is -1. ``d.timetuple()``
+ is equivalent to ``time.struct_time((d.year, d.month, d.day, 0, 0, 0,
+ d.weekday(), d.toordinal() - date(d.year, 1, 1).toordinal() + 1, -1))``
+
+
+.. method:: date.toordinal()
+
+ Return the proleptic Gregorian ordinal of the date, where January 1 of year 1
+ has ordinal 1. For any :class:`date` object *d*,
+ ``date.fromordinal(d.toordinal()) == d``.
+
+
+.. method:: date.weekday()
+
+ Return the day of the week as an integer, where Monday is 0 and Sunday is 6.
+ For example, ``date(2002, 12, 4).weekday() == 2``, a Wednesday. See also
+ :meth:`isoweekday`.
+
+
+.. method:: date.isoweekday()
+
+ Return the day of the week as an integer, where Monday is 1 and Sunday is 7.
+ For example, ``date(2002, 12, 4).isoweekday() == 3``, a Wednesday. See also
+ :meth:`weekday`, :meth:`isocalendar`.
+
+
+.. method:: date.isocalendar()
+
+ Return a 3-tuple, (ISO year, ISO week number, ISO weekday).
+
+ The ISO calendar is a widely used variant of the Gregorian calendar. See
+ http://www.phys.uu.nl/ vgent/calendar/isocalendar.htm for a good explanation.
+
+ The ISO year consists of 52 or 53 full weeks, and where a week starts on a
+ Monday and ends on a Sunday. The first week of an ISO year is the first
+ (Gregorian) calendar week of a year containing a Thursday. This is called week
+ number 1, and the ISO year of that Thursday is the same as its Gregorian year.
+
+ For example, 2004 begins on a Thursday, so the first week of ISO year 2004
+ begins on Monday, 29 Dec 2003 and ends on Sunday, 4 Jan 2004, so that
+ ``date(2003, 12, 29).isocalendar() == (2004, 1, 1)`` and ``date(2004, 1,
+ 4).isocalendar() == (2004, 1, 7)``.
+
+
+.. method:: date.isoformat()
+
+ Return a string representing the date in ISO 8601 format, 'YYYY-MM-DD'. For
+ example, ``date(2002, 12, 4).isoformat() == '2002-12-04'``.
+
+
+.. method:: date.__str__()
+
+ For a date *d*, ``str(d)`` is equivalent to ``d.isoformat()``.
+
+
+.. method:: date.ctime()
+
+ Return a string representing the date, for example ``date(2002, 12,
+ 4).ctime() == 'Wed Dec 4 00:00:00 2002'``. ``d.ctime()`` is equivalent to
+ ``time.ctime(time.mktime(d.timetuple()))`` on platforms where the native C
+ :cfunc:`ctime` function (which :func:`time.ctime` invokes, but which
+ :meth:`date.ctime` does not invoke) conforms to the C standard.
+
+
+.. method:: date.strftime(format)
+
+ Return a string representing the date, controlled by an explicit format string.
+ Format codes referring to hours, minutes or seconds will see 0 values. See
+ section :ref:`strftime-behavior`.
+
+
+.. _datetime-datetime:
+
+:class:`datetime` Objects
+-------------------------
+
+A :class:`datetime` object is a single object containing all the information
+from a :class:`date` object and a :class:`time` object. Like a :class:`date`
+object, :class:`datetime` assumes the current Gregorian calendar extended in
+both directions; like a time object, :class:`datetime` assumes there are exactly
+3600\*24 seconds in every day.
+
+Constructor:
+
+
+.. class:: datetime(year, month, day[, hour[, minute[, second[, microsecond[, tzinfo]]]]])
+
+ The year, month and day arguments are required. *tzinfo* may be ``None``, or an
+ instance of a :class:`tzinfo` subclass. The remaining arguments may be ints or
+ longs, in the following ranges:
+
+ * ``MINYEAR <= year <= MAXYEAR``
+ * ``1 <= month <= 12``
+ * ``1 <= day <= number of days in the given month and year``
+ * ``0 <= hour < 24``
+ * ``0 <= minute < 60``
+ * ``0 <= second < 60``
+ * ``0 <= microsecond < 1000000``
+
+ If an argument outside those ranges is given, :exc:`ValueError` is raised.
+
+Other constructors, all class methods:
+
+
+.. method:: datetime.today()
+
+ Return the current local datetime, with :attr:`tzinfo` ``None``. This is
+ equivalent to ``datetime.fromtimestamp(time.time())``. See also :meth:`now`,
+ :meth:`fromtimestamp`.
+
+
+.. method:: datetime.now([tz])
+
+ Return the current local date and time. If optional argument *tz* is ``None``
+ or not specified, this is like :meth:`today`, but, if possible, supplies more
+ precision than can be gotten from going through a :func:`time.time` timestamp
+ (for example, this may be possible on platforms supplying the C
+ :cfunc:`gettimeofday` function).
+
+ Else *tz* must be an instance of a class :class:`tzinfo` subclass, and the
+ current date and time are converted to *tz*'s time zone. In this case the
+ result is equivalent to ``tz.fromutc(datetime.utcnow().replace(tzinfo=tz))``.
+ See also :meth:`today`, :meth:`utcnow`.
+
+
+.. method:: datetime.utcnow()
+
+ Return the current UTC date and time, with :attr:`tzinfo` ``None``. This is like
+ :meth:`now`, but returns the current UTC date and time, as a naive
+ :class:`datetime` object. See also :meth:`now`.
+
+
+.. method:: datetime.fromtimestamp(timestamp[, tz])
+
+ Return the local date and time corresponding to the POSIX timestamp, such as is
+ returned by :func:`time.time`. If optional argument *tz* is ``None`` or not
+ specified, the timestamp is converted to the platform's local date and time, and
+ the returned :class:`datetime` object is naive.
+
+ Else *tz* must be an instance of a class :class:`tzinfo` subclass, and the
+ timestamp is converted to *tz*'s time zone. In this case the result is
+ equivalent to
+ ``tz.fromutc(datetime.utcfromtimestamp(timestamp).replace(tzinfo=tz))``.
+
+ :meth:`fromtimestamp` may raise :exc:`ValueError`, if the timestamp is out of
+ the range of values supported by the platform C :cfunc:`localtime` or
+ :cfunc:`gmtime` functions. It's common for this to be restricted to years in
+ 1970 through 2038. Note that on non-POSIX systems that include leap seconds in
+ their notion of a timestamp, leap seconds are ignored by :meth:`fromtimestamp`,
+ and then it's possible to have two timestamps differing by a second that yield
+ identical :class:`datetime` objects. See also :meth:`utcfromtimestamp`.
+
+
+.. method:: datetime.utcfromtimestamp(timestamp)
+
+ Return the UTC :class:`datetime` corresponding to the POSIX timestamp, with
+ :attr:`tzinfo` ``None``. This may raise :exc:`ValueError`, if the timestamp is
+ out of the range of values supported by the platform C :cfunc:`gmtime` function.
+ It's common for this to be restricted to years in 1970 through 2038. See also
+ :meth:`fromtimestamp`.
+
+
+.. method:: datetime.fromordinal(ordinal)
+
+ Return the :class:`datetime` corresponding to the proleptic Gregorian ordinal,
+ where January 1 of year 1 has ordinal 1. :exc:`ValueError` is raised unless ``1
+ <= ordinal <= datetime.max.toordinal()``. The hour, minute, second and
+ microsecond of the result are all 0, and :attr:`tzinfo` is ``None``.
+
+
+.. method:: datetime.combine(date, time)
+
+ Return a new :class:`datetime` object whose date members are equal to the given
+ :class:`date` object's, and whose time and :attr:`tzinfo` members are equal to
+ the given :class:`time` object's. For any :class:`datetime` object *d*, ``d ==
+ datetime.combine(d.date(), d.timetz())``. If date is a :class:`datetime`
+ object, its time and :attr:`tzinfo` members are ignored.
+
+
+.. method:: datetime.strptime(date_string, format)
+
+ Return a :class:`datetime` corresponding to *date_string*, parsed according to
+ *format*. This is equivalent to ``datetime(*(time.strptime(date_string,
+ format)[0:6]))``. :exc:`ValueError` is raised if the date_string and format
+ can't be parsed by :func:`time.strptime` or if it returns a value which isn't a
+ time tuple.
+
+ .. versionadded:: 2.5
+
+Class attributes:
+
+
+.. attribute:: datetime.min
+
+ The earliest representable :class:`datetime`, ``datetime(MINYEAR, 1, 1,
+ tzinfo=None)``.
+
+
+.. attribute:: datetime.max
+
+ The latest representable :class:`datetime`, ``datetime(MAXYEAR, 12, 31, 23, 59,
+ 59, 999999, tzinfo=None)``.
+
+
+.. attribute:: datetime.resolution
+
+ The smallest possible difference between non-equal :class:`datetime` objects,
+ ``timedelta(microseconds=1)``.
+
+Instance attributes (read-only):
+
+
+.. attribute:: datetime.year
+
+ Between :const:`MINYEAR` and :const:`MAXYEAR` inclusive.
+
+
+.. attribute:: datetime.month
+
+ Between 1 and 12 inclusive.
+
+
+.. attribute:: datetime.day
+
+ Between 1 and the number of days in the given month of the given year.
+
+
+.. attribute:: datetime.hour
+
+ In ``range(24)``.
+
+
+.. attribute:: datetime.minute
+
+ In ``range(60)``.
+
+
+.. attribute:: datetime.second
+
+ In ``range(60)``.
+
+
+.. attribute:: datetime.microsecond
+
+ In ``range(1000000)``.
+
+
+.. attribute:: datetime.tzinfo
+
+ The object passed as the *tzinfo* argument to the :class:`datetime` constructor,
+ or ``None`` if none was passed.
+
+Supported operations:
+
++---------------------------------------+-------------------------------+
+| Operation | Result |
++=======================================+===============================+
+| ``datetime2 = datetime1 + timedelta`` | \(1) |
++---------------------------------------+-------------------------------+
+| ``datetime2 = datetime1 - timedelta`` | \(2) |
++---------------------------------------+-------------------------------+
+| ``timedelta = datetime1 - datetime2`` | \(3) |
++---------------------------------------+-------------------------------+
+| ``datetime1 < datetime2`` | Compares :class:`datetime` to |
+| | :class:`datetime`. (4) |
++---------------------------------------+-------------------------------+
+
+(1)
+ datetime2 is a duration of timedelta removed from datetime1, moving forward in
+ time if ``timedelta.days`` > 0, or backward if ``timedelta.days`` < 0. The
+ result has the same :attr:`tzinfo` member as the input datetime, and datetime2 -
+ datetime1 == timedelta after. :exc:`OverflowError` is raised if datetime2.year
+ would be smaller than :const:`MINYEAR` or larger than :const:`MAXYEAR`. Note
+ that no time zone adjustments are done even if the input is an aware object.
+
+(2)
+ Computes the datetime2 such that datetime2 + timedelta == datetime1. As for
+ addition, the result has the same :attr:`tzinfo` member as the input datetime,
+ and no time zone adjustments are done even if the input is aware. This isn't
+ quite equivalent to datetime1 + (-timedelta), because -timedelta in isolation
+ can overflow in cases where datetime1 - timedelta does not.
+
+(3)
+ Subtraction of a :class:`datetime` from a :class:`datetime` is defined only if
+ both operands are naive, or if both are aware. If one is aware and the other is
+ naive, :exc:`TypeError` is raised.
+
+ If both are naive, or both are aware and have the same :attr:`tzinfo` member,
+ the :attr:`tzinfo` members are ignored, and the result is a :class:`timedelta`
+ object *t* such that ``datetime2 + t == datetime1``. No time zone adjustments
+ are done in this case.
+
+ If both are aware and have different :attr:`tzinfo` members, ``a-b`` acts as if
+ *a* and *b* were first converted to naive UTC datetimes first. The result is
+ ``(a.replace(tzinfo=None) - a.utcoffset()) - (b.replace(tzinfo=None) -
+ b.utcoffset())`` except that the implementation never overflows.
+
+(4)
+ *datetime1* is considered less than *datetime2* when *datetime1* precedes
+ *datetime2* in time.
+
+ If one comparand is naive and the other is aware, :exc:`TypeError` is raised.
+ If both comparands are aware, and have the same :attr:`tzinfo` member, the
+ common :attr:`tzinfo` member is ignored and the base datetimes are compared. If
+ both comparands are aware and have different :attr:`tzinfo` members, the
+ comparands are first adjusted by subtracting their UTC offsets (obtained from
+ ``self.utcoffset()``).
+
+ .. note::
+
+ In order to stop comparison from falling back to the default scheme of comparing
+ object addresses, datetime comparison normally raises :exc:`TypeError` if the
+ other comparand isn't also a :class:`datetime` object. However,
+ ``NotImplemented`` is returned instead if the other comparand has a
+ :meth:`timetuple` attribute. This hook gives other kinds of date objects a
+ chance at implementing mixed-type comparison. If not, when a :class:`datetime`
+ object is compared to an object of a different type, :exc:`TypeError` is raised
+ unless the comparison is ``==`` or ``!=``. The latter cases return
+ :const:`False` or :const:`True`, respectively.
+
+:class:`datetime` objects can be used as dictionary keys. In Boolean contexts,
+all :class:`datetime` objects are considered to be true.
+
+Instance methods:
+
+
+.. method:: datetime.date()
+
+ Return :class:`date` object with same year, month and day.
+
+
+.. method:: datetime.time()
+
+ Return :class:`time` object with same hour, minute, second and microsecond.
+ :attr:`tzinfo` is ``None``. See also method :meth:`timetz`.
+
+
+.. method:: datetime.timetz()
+
+ Return :class:`time` object with same hour, minute, second, microsecond, and
+ tzinfo members. See also method :meth:`time`.
+
+
+.. method:: datetime.replace([year[, month[, day[, hour[, minute[, second[, microsecond[, tzinfo]]]]]]]])
+
+ Return a datetime with the same members, except for those members given new
+ values by whichever keyword arguments are specified. Note that ``tzinfo=None``
+ can be specified to create a naive datetime from an aware datetime with no
+ conversion of date and time members.
+
+
+.. method:: datetime.astimezone(tz)
+
+ Return a :class:`datetime` object with new :attr:`tzinfo` member *tz*, adjusting
+ the date and time members so the result is the same UTC time as *self*, but in
+ *tz*'s local time.
+
+ *tz* must be an instance of a :class:`tzinfo` subclass, and its
+ :meth:`utcoffset` and :meth:`dst` methods must not return ``None``. *self* must
+ be aware (``self.tzinfo`` must not be ``None``, and ``self.utcoffset()`` must
+ not return ``None``).
+
+ If ``self.tzinfo`` is *tz*, ``self.astimezone(tz)`` is equal to *self*: no
+ adjustment of date or time members is performed. Else the result is local time
+ in time zone *tz*, representing the same UTC time as *self*: after ``astz =
+ dt.astimezone(tz)``, ``astz - astz.utcoffset()`` will usually have the same date
+ and time members as ``dt - dt.utcoffset()``. The discussion of class
+ :class:`tzinfo` explains the cases at Daylight Saving Time transition boundaries
+ where this cannot be achieved (an issue only if *tz* models both standard and
+ daylight time).
+
+ If you merely want to attach a time zone object *tz* to a datetime *dt* without
+ adjustment of date and time members, use ``dt.replace(tzinfo=tz)``. If you
+ merely want to remove the time zone object from an aware datetime *dt* without
+ conversion of date and time members, use ``dt.replace(tzinfo=None)``.
+
+ Note that the default :meth:`tzinfo.fromutc` method can be overridden in a
+ :class:`tzinfo` subclass to affect the result returned by :meth:`astimezone`.
+ Ignoring error cases, :meth:`astimezone` acts like::
+
+ def astimezone(self, tz):
+ if self.tzinfo is tz:
+ return self
+ # Convert self to UTC, and attach the new time zone object.
+ utc = (self - self.utcoffset()).replace(tzinfo=tz)
+ # Convert from UTC to tz's local time.
+ return tz.fromutc(utc)
+
+
+.. method:: datetime.utcoffset()
+
+ If :attr:`tzinfo` is ``None``, returns ``None``, else returns
+ ``self.tzinfo.utcoffset(self)``, and raises an exception if the latter doesn't
+ return ``None``, or a :class:`timedelta` object representing a whole number of
+ minutes with magnitude less than one day.
+
+
+.. method:: datetime.dst()
+
+ If :attr:`tzinfo` is ``None``, returns ``None``, else returns
+ ``self.tzinfo.dst(self)``, and raises an exception if the latter doesn't return
+ ``None``, or a :class:`timedelta` object representing a whole number of minutes
+ with magnitude less than one day.
+
+
+.. method:: datetime.tzname()
+
+ If :attr:`tzinfo` is ``None``, returns ``None``, else returns
+ ``self.tzinfo.tzname(self)``, raises an exception if the latter doesn't return
+ ``None`` or a string object,
+
+
+.. method:: datetime.timetuple()
+
+ Return a :class:`time.struct_time` such as returned by :func:`time.localtime`.
+ ``d.timetuple()`` is equivalent to ``time.struct_time((d.year, d.month, d.day,
+ d.hour, d.minute, d.second, d.weekday(), d.toordinal() - date(d.year, 1,
+ 1).toordinal() + 1, dst))`` The :attr:`tm_isdst` flag of the result is set
+ according to the :meth:`dst` method: :attr:`tzinfo` is ``None`` or :meth:`dst`
+ returns ``None``, :attr:`tm_isdst` is set to ``-1``; else if :meth:`dst`
+ returns a non-zero value, :attr:`tm_isdst` is set to ``1``; else ``tm_isdst`` is
+ set to ``0``.
+
+
+.. method:: datetime.utctimetuple()
+
+ If :class:`datetime` instance *d* is naive, this is the same as
+ ``d.timetuple()`` except that :attr:`tm_isdst` is forced to 0 regardless of what
+ ``d.dst()`` returns. DST is never in effect for a UTC time.
+
+ If *d* is aware, *d* is normalized to UTC time, by subtracting
+ ``d.utcoffset()``, and a :class:`time.struct_time` for the normalized time is
+ returned. :attr:`tm_isdst` is forced to 0. Note that the result's
+ :attr:`tm_year` member may be :const:`MINYEAR`\ -1 or :const:`MAXYEAR`\ +1, if
+ *d*.year was ``MINYEAR`` or ``MAXYEAR`` and UTC adjustment spills over a year
+ boundary.
+
+
+.. method:: datetime.toordinal()
+
+ Return the proleptic Gregorian ordinal of the date. The same as
+ ``self.date().toordinal()``.
+
+
+.. method:: datetime.weekday()
+
+ Return the day of the week as an integer, where Monday is 0 and Sunday is 6.
+ The same as ``self.date().weekday()``. See also :meth:`isoweekday`.
+
+
+.. method:: datetime.isoweekday()
+
+ Return the day of the week as an integer, where Monday is 1 and Sunday is 7.
+ The same as ``self.date().isoweekday()``. See also :meth:`weekday`,
+ :meth:`isocalendar`.
+
+
+.. method:: datetime.isocalendar()
+
+ Return a 3-tuple, (ISO year, ISO week number, ISO weekday). The same as
+ ``self.date().isocalendar()``.
+
+
+.. method:: datetime.isoformat([sep])
+
+ Return a string representing the date and time in ISO 8601 format,
+ YYYY-MM-DDTHH:MM:SS.mmmmmm or, if :attr:`microsecond` is 0,
+ YYYY-MM-DDTHH:MM:SS
+
+ If :meth:`utcoffset` does not return ``None``, a 6-character string is
+ appended, giving the UTC offset in (signed) hours and minutes:
+ YYYY-MM-DDTHH:MM:SS.mmmmmm+HH:MM or, if :attr:`microsecond` is 0
+ YYYY-MM-DDTHH:MM:SS+HH:MM
+
+ The optional argument *sep* (default ``'T'``) is a one-character separator,
+ placed between the date and time portions of the result. For example, ::
+
+ >>> from datetime import tzinfo, timedelta, datetime
+ >>> class TZ(tzinfo):
+ ... def utcoffset(self, dt): return timedelta(minutes=-399)
+ ...
+ >>> datetime(2002, 12, 25, tzinfo=TZ()).isoformat(' ')
+ '2002-12-25 00:00:00-06:39'
+
+
+.. method:: datetime.__str__()
+
+ For a :class:`datetime` instance *d*, ``str(d)`` is equivalent to
+ ``d.isoformat(' ')``.
+
+
+.. method:: datetime.ctime()
+
+ Return a string representing the date and time, for example ``datetime(2002, 12,
+ 4, 20, 30, 40).ctime() == 'Wed Dec 4 20:30:40 2002'``. ``d.ctime()`` is
+ equivalent to ``time.ctime(time.mktime(d.timetuple()))`` on platforms where the
+ native C :cfunc:`ctime` function (which :func:`time.ctime` invokes, but which
+ :meth:`datetime.ctime` does not invoke) conforms to the C standard.
+
+
+.. method:: datetime.strftime(format)
+
+ Return a string representing the date and time, controlled by an explicit format
+ string. See section :ref:`strftime-behavior`.
+
+
+.. _datetime-time:
+
+:class:`time` Objects
+---------------------
+
+A time object represents a (local) time of day, independent of any particular
+day, and subject to adjustment via a :class:`tzinfo` object.
+
+
+.. class:: time(hour[, minute[, second[, microsecond[, tzinfo]]]])
+
+ All arguments are optional. *tzinfo* may be ``None``, or an instance of a
+ :class:`tzinfo` subclass. The remaining arguments may be ints or longs, in the
+ following ranges:
+
+ * ``0 <= hour < 24``
+ * ``0 <= minute < 60``
+ * ``0 <= second < 60``
+ * ``0 <= microsecond < 1000000``.
+
+ If an argument outside those ranges is given, :exc:`ValueError` is raised. All
+ default to ``0`` except *tzinfo*, which defaults to :const:`None`.
+
+Class attributes:
+
+
+.. attribute:: time.min
+
+ The earliest representable :class:`time`, ``time(0, 0, 0, 0)``.
+
+
+.. attribute:: time.max
+
+ The latest representable :class:`time`, ``time(23, 59, 59, 999999)``.
+
+
+.. attribute:: time.resolution
+
+ The smallest possible difference between non-equal :class:`time` objects,
+ ``timedelta(microseconds=1)``, although note that arithmetic on :class:`time`
+ objects is not supported.
+
+Instance attributes (read-only):
+
+
+.. attribute:: time.hour
+
+ In ``range(24)``.
+
+
+.. attribute:: time.minute
+
+ In ``range(60)``.
+
+
+.. attribute:: time.second
+
+ In ``range(60)``.
+
+
+.. attribute:: time.microsecond
+
+ In ``range(1000000)``.
+
+
+.. attribute:: time.tzinfo
+
+ The object passed as the tzinfo argument to the :class:`time` constructor, or
+ ``None`` if none was passed.
+
+Supported operations:
+
+* comparison of :class:`time` to :class:`time`, where *a* is considered less
+ than *b* when *a* precedes *b* in time. If one comparand is naive and the other
+ is aware, :exc:`TypeError` is raised. If both comparands are aware, and have
+ the same :attr:`tzinfo` member, the common :attr:`tzinfo` member is ignored and
+ the base times are compared. If both comparands are aware and have different
+ :attr:`tzinfo` members, the comparands are first adjusted by subtracting their
+ UTC offsets (obtained from ``self.utcoffset()``). In order to stop mixed-type
+ comparisons from falling back to the default comparison by object address, when
+ a :class:`time` object is compared to an object of a different type,
+ :exc:`TypeError` is raised unless the comparison is ``==`` or ``!=``. The
+ latter cases return :const:`False` or :const:`True`, respectively.
+
+* hash, use as dict key
+
+* efficient pickling
+
+* in Boolean contexts, a :class:`time` object is considered to be true if and
+ only if, after converting it to minutes and subtracting :meth:`utcoffset` (or
+ ``0`` if that's ``None``), the result is non-zero.
+
+Instance methods:
+
+
+.. method:: time.replace([hour[, minute[, second[, microsecond[, tzinfo]]]]])
+
+ Return a :class:`time` with the same value, except for those members given new
+ values by whichever keyword arguments are specified. Note that ``tzinfo=None``
+ can be specified to create a naive :class:`time` from an aware :class:`time`,
+ without conversion of the time members.
+
+
+.. method:: time.isoformat()
+
+ Return a string representing the time in ISO 8601 format, HH:MM:SS.mmmmmm or, if
+ self.microsecond is 0, HH:MM:SS If :meth:`utcoffset` does not return ``None``, a
+ 6-character string is appended, giving the UTC offset in (signed) hours and
+ minutes: HH:MM:SS.mmmmmm+HH:MM or, if self.microsecond is 0, HH:MM:SS+HH:MM
+
+
+.. method:: time.__str__()
+
+ For a time *t*, ``str(t)`` is equivalent to ``t.isoformat()``.
+
+
+.. method:: time.strftime(format)
+
+ Return a string representing the time, controlled by an explicit format string.
+ See section :ref:`strftime-behavior`.
+
+
+.. method:: time.utcoffset()
+
+ If :attr:`tzinfo` is ``None``, returns ``None``, else returns
+ ``self.tzinfo.utcoffset(None)``, and raises an exception if the latter doesn't
+ return ``None`` or a :class:`timedelta` object representing a whole number of
+ minutes with magnitude less than one day.
+
+
+.. method:: time.dst()
+
+ If :attr:`tzinfo` is ``None``, returns ``None``, else returns
+ ``self.tzinfo.dst(None)``, and raises an exception if the latter doesn't return
+ ``None``, or a :class:`timedelta` object representing a whole number of minutes
+ with magnitude less than one day.
+
+
+.. method:: time.tzname()
+
+ If :attr:`tzinfo` is ``None``, returns ``None``, else returns
+ ``self.tzinfo.tzname(None)``, or raises an exception if the latter doesn't
+ return ``None`` or a string object.
+
+
+.. _datetime-tzinfo:
+
+:class:`tzinfo` Objects
+-----------------------
+
+:class:`tzinfo` is an abstract base clase, meaning that this class should not be
+instantiated directly. You need to derive a concrete subclass, and (at least)
+supply implementations of the standard :class:`tzinfo` methods needed by the
+:class:`datetime` methods you use. The :mod:`datetime` module does not supply
+any concrete subclasses of :class:`tzinfo`.
+
+An instance of (a concrete subclass of) :class:`tzinfo` can be passed to the
+constructors for :class:`datetime` and :class:`time` objects. The latter objects
+view their members as being in local time, and the :class:`tzinfo` object
+supports methods revealing offset of local time from UTC, the name of the time
+zone, and DST offset, all relative to a date or time object passed to them.
+
+Special requirement for pickling: A :class:`tzinfo` subclass must have an
+:meth:`__init__` method that can be called with no arguments, else it can be
+pickled but possibly not unpickled again. This is a technical requirement that
+may be relaxed in the future.
+
+A concrete subclass of :class:`tzinfo` may need to implement the following
+methods. Exactly which methods are needed depends on the uses made of aware
+:mod:`datetime` objects. If in doubt, simply implement all of them.
+
+
+.. method:: tzinfo.utcoffset(self, dt)
+
+ Return offset of local time from UTC, in minutes east of UTC. If local time is
+ west of UTC, this should be negative. Note that this is intended to be the
+ total offset from UTC; for example, if a :class:`tzinfo` object represents both
+ time zone and DST adjustments, :meth:`utcoffset` should return their sum. If
+ the UTC offset isn't known, return ``None``. Else the value returned must be a
+ :class:`timedelta` object specifying a whole number of minutes in the range
+ -1439 to 1439 inclusive (1440 = 24\*60; the magnitude of the offset must be less
+ than one day). Most implementations of :meth:`utcoffset` will probably look
+ like one of these two::
+
+ return CONSTANT # fixed-offset class
+ return CONSTANT + self.dst(dt) # daylight-aware class
+
+ If :meth:`utcoffset` does not return ``None``, :meth:`dst` should not return
+ ``None`` either.
+
+ The default implementation of :meth:`utcoffset` raises
+ :exc:`NotImplementedError`.
+
+
+.. method:: tzinfo.dst(self, dt)
+
+ Return the daylight saving time (DST) adjustment, in minutes east of UTC, or
+ ``None`` if DST information isn't known. Return ``timedelta(0)`` if DST is not
+ in effect. If DST is in effect, return the offset as a :class:`timedelta` object
+ (see :meth:`utcoffset` for details). Note that DST offset, if applicable, has
+ already been added to the UTC offset returned by :meth:`utcoffset`, so there's
+ no need to consult :meth:`dst` unless you're interested in obtaining DST info
+ separately. For example, :meth:`datetime.timetuple` calls its :attr:`tzinfo`
+ member's :meth:`dst` method to determine how the :attr:`tm_isdst` flag should be
+ set, and :meth:`tzinfo.fromutc` calls :meth:`dst` to account for DST changes
+ when crossing time zones.
+
+ An instance *tz* of a :class:`tzinfo` subclass that models both standard and
+ daylight times must be consistent in this sense:
+
+ ``tz.utcoffset(dt) - tz.dst(dt)``
+
+ must return the same result for every :class:`datetime` *dt* with ``dt.tzinfo ==
+ tz`` For sane :class:`tzinfo` subclasses, this expression yields the time
+ zone's "standard offset", which should not depend on the date or the time, but
+ only on geographic location. The implementation of :meth:`datetime.astimezone`
+ relies on this, but cannot detect violations; it's the programmer's
+ responsibility to ensure it. If a :class:`tzinfo` subclass cannot guarantee
+ this, it may be able to override the default implementation of
+ :meth:`tzinfo.fromutc` to work correctly with :meth:`astimezone` regardless.
+
+ Most implementations of :meth:`dst` will probably look like one of these two::
+
+ def dst(self):
+ # a fixed-offset class: doesn't account for DST
+ return timedelta(0)
+
+ or ::
+
+ def dst(self):
+ # Code to set dston and dstoff to the time zone's DST
+ # transition times based on the input dt.year, and expressed
+ # in standard local time. Then
+
+ if dston <= dt.replace(tzinfo=None) < dstoff:
+ return timedelta(hours=1)
+ else:
+ return timedelta(0)
+
+ The default implementation of :meth:`dst` raises :exc:`NotImplementedError`.
+
+
+.. method:: tzinfo.tzname(self, dt)
+
+ Return the time zone name corresponding to the :class:`datetime` object *dt*, as
+ a string. Nothing about string names is defined by the :mod:`datetime` module,
+ and there's no requirement that it mean anything in particular. For example,
+ "GMT", "UTC", "-500", "-5:00", "EDT", "US/Eastern", "America/New York" are all
+ valid replies. Return ``None`` if a string name isn't known. Note that this is
+ a method rather than a fixed string primarily because some :class:`tzinfo`
+ subclasses will wish to return different names depending on the specific value
+ of *dt* passed, especially if the :class:`tzinfo` class is accounting for
+ daylight time.
+
+ The default implementation of :meth:`tzname` raises :exc:`NotImplementedError`.
+
+These methods are called by a :class:`datetime` or :class:`time` object, in
+response to their methods of the same names. A :class:`datetime` object passes
+itself as the argument, and a :class:`time` object passes ``None`` as the
+argument. A :class:`tzinfo` subclass's methods should therefore be prepared to
+accept a *dt* argument of ``None``, or of class :class:`datetime`.
+
+When ``None`` is passed, it's up to the class designer to decide the best
+response. For example, returning ``None`` is appropriate if the class wishes to
+say that time objects don't participate in the :class:`tzinfo` protocols. It
+may be more useful for ``utcoffset(None)`` to return the standard UTC offset, as
+there is no other convention for discovering the standard offset.
+
+When a :class:`datetime` object is passed in response to a :class:`datetime`
+method, ``dt.tzinfo`` is the same object as *self*. :class:`tzinfo` methods can
+rely on this, unless user code calls :class:`tzinfo` methods directly. The
+intent is that the :class:`tzinfo` methods interpret *dt* as being in local
+time, and not need worry about objects in other timezones.
+
+There is one more :class:`tzinfo` method that a subclass may wish to override:
+
+
+.. method:: tzinfo.fromutc(self, dt)
+
+ This is called from the default :class:`datetime.astimezone()` implementation.
+ When called from that, ``dt.tzinfo`` is *self*, and *dt*'s date and time members
+ are to be viewed as expressing a UTC time. The purpose of :meth:`fromutc` is to
+ adjust the date and time members, returning an equivalent datetime in *self*'s
+ local time.
+
+ Most :class:`tzinfo` subclasses should be able to inherit the default
+ :meth:`fromutc` implementation without problems. It's strong enough to handle
+ fixed-offset time zones, and time zones accounting for both standard and
+ daylight time, and the latter even if the DST transition times differ in
+ different years. An example of a time zone the default :meth:`fromutc`
+ implementation may not handle correctly in all cases is one where the standard
+ offset (from UTC) depends on the specific date and time passed, which can happen
+ for political reasons. The default implementations of :meth:`astimezone` and
+ :meth:`fromutc` may not produce the result you want if the result is one of the
+ hours straddling the moment the standard offset changes.
+
+ Skipping code for error cases, the default :meth:`fromutc` implementation acts
+ like::
+
+ def fromutc(self, dt):
+ # raise ValueError error if dt.tzinfo is not self
+ dtoff = dt.utcoffset()
+ dtdst = dt.dst()
+ # raise ValueError if dtoff is None or dtdst is None
+ delta = dtoff - dtdst # this is self's standard offset
+ if delta:
+ dt += delta # convert to standard local time
+ dtdst = dt.dst()
+ # raise ValueError if dtdst is None
+ if dtdst:
+ return dt + dtdst
+ else:
+ return dt
+
+Example :class:`tzinfo` classes:
+
+.. literalinclude:: ../includes/tzinfo-examples.py
+
+
+Note that there are unavoidable subtleties twice per year in a :class:`tzinfo`
+subclass accounting for both standard and daylight time, at the DST transition
+points. For concreteness, consider US Eastern (UTC -0500), where EDT begins the
+minute after 1:59 (EST) on the first Sunday in April, and ends the minute after
+1:59 (EDT) on the last Sunday in October::
+
+ UTC 3:MM 4:MM 5:MM 6:MM 7:MM 8:MM
+ EST 22:MM 23:MM 0:MM 1:MM 2:MM 3:MM
+ EDT 23:MM 0:MM 1:MM 2:MM 3:MM 4:MM
+
+ start 22:MM 23:MM 0:MM 1:MM 3:MM 4:MM
+
+ end 23:MM 0:MM 1:MM 1:MM 2:MM 3:MM
+
+When DST starts (the "start" line), the local wall clock leaps from 1:59 to
+3:00. A wall time of the form 2:MM doesn't really make sense on that day, so
+``astimezone(Eastern)`` won't deliver a result with ``hour == 2`` on the day DST
+begins. In order for :meth:`astimezone` to make this guarantee, the
+:meth:`rzinfo.dst` method must consider times in the "missing hour" (2:MM for
+Eastern) to be in daylight time.
+
+When DST ends (the "end" line), there's a potentially worse problem: there's an
+hour that can't be spelled unambiguously in local wall time: the last hour of
+daylight time. In Eastern, that's times of the form 5:MM UTC on the day
+daylight time ends. The local wall clock leaps from 1:59 (daylight time) back
+to 1:00 (standard time) again. Local times of the form 1:MM are ambiguous.
+:meth:`astimezone` mimics the local clock's behavior by mapping two adjacent UTC
+hours into the same local hour then. In the Eastern example, UTC times of the
+form 5:MM and 6:MM both map to 1:MM when converted to Eastern. In order for
+:meth:`astimezone` to make this guarantee, the :meth:`tzinfo.dst` method must
+consider times in the "repeated hour" to be in standard time. This is easily
+arranged, as in the example, by expressing DST switch times in the time zone's
+standard local time.
+
+Applications that can't bear such ambiguities should avoid using hybrid
+:class:`tzinfo` subclasses; there are no ambiguities when using UTC, or any
+other fixed-offset :class:`tzinfo` subclass (such as a class representing only
+EST (fixed offset -5 hours), or only EDT (fixed offset -4 hours)).
+
+
+.. _strftime-behavior:
+
+:meth:`strftime` Behavior
+-------------------------
+
+:class:`date`, :class:`datetime`, and :class:`time` objects all support a
+``strftime(format)`` method, to create a string representing the time under the
+control of an explicit format string. Broadly speaking, ``d.strftime(fmt)``
+acts like the :mod:`time` module's ``time.strftime(fmt, d.timetuple())``
+although not all objects support a :meth:`timetuple` method.
+
+For :class:`time` objects, the format codes for year, month, and day should not
+be used, as time objects have no such values. If they're used anyway, ``1900``
+is substituted for the year, and ``0`` for the month and day.
+
+For :class:`date` objects, the format codes for hours, minutes, and seconds
+should not be used, as :class:`date` objects have no such values. If they're
+used anyway, ``0`` is substituted for them.
+
+For a naive object, the ``%z`` and ``%Z`` format codes are replaced by empty
+strings.
+
+For an aware object:
+
+``%z``
+ :meth:`utcoffset` is transformed into a 5-character string of the form +HHMM or
+ -HHMM, where HH is a 2-digit string giving the number of UTC offset hours, and
+ MM is a 2-digit string giving the number of UTC offset minutes. For example, if
+ :meth:`utcoffset` returns ``timedelta(hours=-3, minutes=-30)``, ``%z`` is
+ replaced with the string ``'-0330'``.
+
+``%Z``
+ If :meth:`tzname` returns ``None``, ``%Z`` is replaced by an empty string.
+ Otherwise ``%Z`` is replaced by the returned value, which must be a string.
+
+The full set of format codes supported varies across platforms, because Python
+calls the platform C library's :func:`strftime` function, and platform
+variations are common. The documentation for Python's :mod:`time` module lists
+the format codes that the C standard (1989 version) requires, and those work on
+all platforms with a standard C implementation. Note that the 1999 version of
+the C standard added additional format codes.
+
+The exact range of years for which :meth:`strftime` works also varies across
+platforms. Regardless of platform, years before 1900 cannot be used.
+
+.. % %% This example is obsolete, since strptime is now supported by datetime.
+.. %
+.. % \subsection{Examples}
+.. %
+.. % \subsubsection{Creating Datetime Objects from Formatted Strings}
+.. %
+.. % The \class{datetime} class does not directly support parsing formatted time
+.. % strings. You can use \function{time.strptime} to do the parsing and create
+.. % a \class{datetime} object from the tuple it returns:
+.. %
+.. % \begin{verbatim}
+.. % >>> s = "2005-12-06T12:13:14"
+.. % >>> from datetime import datetime
+.. % >>> from time import strptime
+.. % >>> datetime(*strptime(s, "%Y-%m-%dT%H:%M:%S")[0:6])
+.. % datetime.datetime(2005, 12, 6, 12, 13, 14)
+.. % \end{verbatim}
+.. %
+
diff --git a/Doc/library/dbhash.rst b/Doc/library/dbhash.rst
new file mode 100644
index 0000000000..b5c95902d0
--- /dev/null
+++ b/Doc/library/dbhash.rst
@@ -0,0 +1,114 @@
+
+:mod:`dbhash` --- DBM-style interface to the BSD database library
+=================================================================
+
+.. module:: dbhash
+ :synopsis: DBM-style interface to the BSD database library.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. index:: module: bsddb
+
+The :mod:`dbhash` module provides a function to open databases using the BSD
+``db`` library. This module mirrors the interface of the other Python database
+modules that provide access to DBM-style databases. The :mod:`bsddb` module is
+required to use :mod:`dbhash`.
+
+This module provides an exception and a function:
+
+
+.. exception:: error
+
+ Exception raised on database errors other than :exc:`KeyError`. It is a synonym
+ for :exc:`bsddb.error`.
+
+
+.. function:: open(path[, flag[, mode]])
+
+ Open a ``db`` database and return the database object. The *path* argument is
+ the name of the database file.
+
+ The *flag* argument can be:
+
+ +---------+-------------------------------------------+
+ | Value | Meaning |
+ +=========+===========================================+
+ | ``'r'`` | Open existing database for reading only |
+ | | (default) |
+ +---------+-------------------------------------------+
+ | ``'w'`` | Open existing database for reading and |
+ | | writing |
+ +---------+-------------------------------------------+
+ | ``'c'`` | Open database for reading and writing, |
+ | | creating it if it doesn't exist |
+ +---------+-------------------------------------------+
+ | ``'n'`` | Always create a new, empty database, open |
+ | | for reading and writing |
+ +---------+-------------------------------------------+
+
+ For platforms on which the BSD ``db`` library supports locking, an ``'l'``
+ can be appended to indicate that locking should be used.
+
+ The optional *mode* parameter is used to indicate the Unix permission bits that
+ should be set if a new database must be created; this will be masked by the
+ current umask value for the process.
+
+
+.. seealso::
+
+ Module :mod:`anydbm`
+ Generic interface to ``dbm``\ -style databases.
+
+ Module :mod:`bsddb`
+ Lower-level interface to the BSD ``db`` library.
+
+ Module :mod:`whichdb`
+ Utility module used to determine the type of an existing database.
+
+
+.. _dbhash-objects:
+
+Database Objects
+----------------
+
+The database objects returned by :func:`open` provide the methods common to all
+the DBM-style databases and mapping objects. The following methods are
+available in addition to the standard methods.
+
+
+.. method:: dbhash.first()
+
+ It's possible to loop over every key/value pair in the database using this
+ method and the :meth:`next` method. The traversal is ordered by the databases
+ internal hash values, and won't be sorted by the key values. This method
+ returns the starting key.
+
+
+.. method:: dbhash.last()
+
+ Return the last key/value pair in a database traversal. This may be used to
+ begin a reverse-order traversal; see :meth:`previous`.
+
+
+.. method:: dbhash.next()
+
+ Returns the key next key/value pair in a database traversal. The following code
+ prints every key in the database ``db``, without having to create a list in
+ memory that contains them all::
+
+ print db.first()
+ for i in range(1, len(db)):
+ print db.next()
+
+
+.. method:: dbhash.previous()
+
+ Returns the previous key/value pair in a forward-traversal of the database. In
+ conjunction with :meth:`last`, this may be used to implement a reverse-order
+ traversal.
+
+
+.. method:: dbhash.sync()
+
+ This method forces any unwritten data to be written to the disk.
+
diff --git a/Doc/library/dbm.rst b/Doc/library/dbm.rst
new file mode 100644
index 0000000000..52923e826d
--- /dev/null
+++ b/Doc/library/dbm.rst
@@ -0,0 +1,74 @@
+
+:mod:`dbm` --- Simple "database" interface
+==========================================
+
+.. module:: dbm
+ :platform: Unix
+ :synopsis: The standard "database" interface, based on ndbm.
+
+
+The :mod:`dbm` module provides an interface to the Unix "(n)dbm" library. Dbm
+objects behave like mappings (dictionaries), except that keys and values are
+always strings. Printing a dbm object doesn't print the keys and values, and the
+:meth:`items` and :meth:`values` methods are not supported.
+
+This module can be used with the "classic" ndbm interface, the BSD DB
+compatibility interface, or the GNU GDBM compatibility interface. On Unix, the
+:program:`configure` script will attempt to locate the appropriate header file
+to simplify building this module.
+
+The module defines the following:
+
+
+.. exception:: error
+
+ Raised on dbm-specific errors, such as I/O errors. :exc:`KeyError` is raised for
+ general mapping errors like specifying an incorrect key.
+
+
+.. data:: library
+
+ Name of the ``ndbm`` implementation library used.
+
+
+.. function:: open(filename[, flag[, mode]])
+
+ Open a dbm database and return a dbm object. The *filename* argument is the
+ name of the database file (without the :file:`.dir` or :file:`.pag` extensions;
+ note that the BSD DB implementation of the interface will append the extension
+ :file:`.db` and only create one file).
+
+ The optional *flag* argument must be one of these values:
+
+ +---------+-------------------------------------------+
+ | Value | Meaning |
+ +=========+===========================================+
+ | ``'r'`` | Open existing database for reading only |
+ | | (default) |
+ +---------+-------------------------------------------+
+ | ``'w'`` | Open existing database for reading and |
+ | | writing |
+ +---------+-------------------------------------------+
+ | ``'c'`` | Open database for reading and writing, |
+ | | creating it if it doesn't exist |
+ +---------+-------------------------------------------+
+ | ``'n'`` | Always create a new, empty database, open |
+ | | for reading and writing |
+ +---------+-------------------------------------------+
+
+ The optional *mode* argument is the Unix mode of the file, used only when the
+ database has to be created. It defaults to octal ``0666`` (and will be
+ modified by the prevailing umask).
+
+
+.. seealso::
+
+ Module :mod:`anydbm`
+ Generic interface to ``dbm``\ -style databases.
+
+ Module :mod:`gdbm`
+ Similar interface to the GNU GDBM library.
+
+ Module :mod:`whichdb`
+ Utility module used to determine the type of an existing database.
+
diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
new file mode 100644
index 0000000000..1d17109a12
--- /dev/null
+++ b/Doc/library/decimal.rst
@@ -0,0 +1,1289 @@
+
+:mod:`decimal` --- Decimal floating point arithmetic
+====================================================
+
+.. module:: decimal
+ :synopsis: Implementation of the General Decimal Arithmetic Specification.
+
+
+.. moduleauthor:: Eric Price <eprice at tjhsst.edu>
+.. moduleauthor:: Facundo Batista <facundo at taniquetil.com.ar>
+.. moduleauthor:: Raymond Hettinger <python at rcn.com>
+.. moduleauthor:: Aahz <aahz at pobox.com>
+.. moduleauthor:: Tim Peters <tim.one at comcast.net>
+
+
+.. sectionauthor:: Raymond D. Hettinger <python at rcn.com>
+
+
+.. versionadded:: 2.4
+
+The :mod:`decimal` module provides support for decimal floating point
+arithmetic. It offers several advantages over the :class:`float()` datatype:
+
+* Decimal numbers can be represented exactly. In contrast, numbers like
+ :const:`1.1` do not have an exact representation in binary floating point. End
+ users typically would not expect :const:`1.1` to display as
+ :const:`1.1000000000000001` as it does with binary floating point.
+
+* The exactness carries over into arithmetic. In decimal floating point, ``0.1
+ + 0.1 + 0.1 - 0.3`` is exactly equal to zero. In binary floating point, result
+ is :const:`5.5511151231257827e-017`. While near to zero, the differences
+ prevent reliable equality testing and differences can accumulate. For this
+ reason, decimal would be preferred in accounting applications which have strict
+ equality invariants.
+
+* The decimal module incorporates a notion of significant places so that ``1.30
+ + 1.20`` is :const:`2.50`. The trailing zero is kept to indicate significance.
+ This is the customary presentation for monetary applications. For
+ multiplication, the "schoolbook" approach uses all the figures in the
+ multiplicands. For instance, ``1.3 * 1.2`` gives :const:`1.56` while ``1.30 *
+ 1.20`` gives :const:`1.5600`.
+
+* Unlike hardware based binary floating point, the decimal module has a user
+ settable precision (defaulting to 28 places) which can be as large as needed for
+ a given problem::
+
+ >>> getcontext().prec = 6
+ >>> Decimal(1) / Decimal(7)
+ Decimal("0.142857")
+ >>> getcontext().prec = 28
+ >>> Decimal(1) / Decimal(7)
+ Decimal("0.1428571428571428571428571429")
+
+* Both binary and decimal floating point are implemented in terms of published
+ standards. While the built-in float type exposes only a modest portion of its
+ capabilities, the decimal module exposes all required parts of the standard.
+ When needed, the programmer has full control over rounding and signal handling.
+
+The module design is centered around three concepts: the decimal number, the
+context for arithmetic, and signals.
+
+A decimal number is immutable. It has a sign, coefficient digits, and an
+exponent. To preserve significance, the coefficient digits do not truncate
+trailing zeroes. Decimals also include special values such as
+:const:`Infinity`, :const:`-Infinity`, and :const:`NaN`. The standard also
+differentiates :const:`-0` from :const:`+0`.
+
+The context for arithmetic is an environment specifying precision, rounding
+rules, limits on exponents, flags indicating the results of operations, and trap
+enablers which determine whether signals are treated as exceptions. Rounding
+options include :const:`ROUND_CEILING`, :const:`ROUND_DOWN`,
+:const:`ROUND_FLOOR`, :const:`ROUND_HALF_DOWN`, :const:`ROUND_HALF_EVEN`,
+:const:`ROUND_HALF_UP`, and :const:`ROUND_UP`.
+
+Signals are groups of exceptional conditions arising during the course of
+computation. Depending on the needs of the application, signals may be ignored,
+considered as informational, or treated as exceptions. The signals in the
+decimal module are: :const:`Clamped`, :const:`InvalidOperation`,
+:const:`DivisionByZero`, :const:`Inexact`, :const:`Rounded`, :const:`Subnormal`,
+:const:`Overflow`, and :const:`Underflow`.
+
+For each signal there is a flag and a trap enabler. When a signal is
+encountered, its flag is incremented from zero and, then, if the trap enabler is
+set to one, an exception is raised. Flags are sticky, so the user needs to
+reset them before monitoring a calculation.
+
+
+.. seealso::
+
+ IBM's General Decimal Arithmetic Specification, `The General Decimal Arithmetic
+ Specification <http://www2.hursley.ibm.com/decimal/decarith.html>`_.
+
+ IEEE standard 854-1987, `Unofficial IEEE 854 Text
+ <http://www.cs.berkeley.edu/~ejr/projects/754/private/drafts/854-1987/dir.html>`_.
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-tutorial:
+
+Quick-start Tutorial
+--------------------
+
+The usual start to using decimals is importing the module, viewing the current
+context with :func:`getcontext` and, if necessary, setting new values for
+precision, rounding, or enabled traps::
+
+ >>> from decimal import *
+ >>> getcontext()
+ Context(prec=28, rounding=ROUND_HALF_EVEN, Emin=-999999999, Emax=999999999,
+ capitals=1, flags=[], traps=[Overflow, InvalidOperation,
+ DivisionByZero])
+
+ >>> getcontext().prec = 7 # Set a new precision
+
+Decimal instances can be constructed from integers, strings, or tuples. To
+create a Decimal from a :class:`float`, first convert it to a string. This
+serves as an explicit reminder of the details of the conversion (including
+representation error). Decimal numbers include special values such as
+:const:`NaN` which stands for "Not a number", positive and negative
+:const:`Infinity`, and :const:`-0`. ::
+
+ >>> Decimal(10)
+ Decimal("10")
+ >>> Decimal("3.14")
+ Decimal("3.14")
+ >>> Decimal((0, (3, 1, 4), -2))
+ Decimal("3.14")
+ >>> Decimal(str(2.0 ** 0.5))
+ Decimal("1.41421356237")
+ >>> Decimal("NaN")
+ Decimal("NaN")
+ >>> Decimal("-Infinity")
+ Decimal("-Infinity")
+
+The significance of a new Decimal is determined solely by the number of digits
+input. Context precision and rounding only come into play during arithmetic
+operations. ::
+
+ >>> getcontext().prec = 6
+ >>> Decimal('3.0')
+ Decimal("3.0")
+ >>> Decimal('3.1415926535')
+ Decimal("3.1415926535")
+ >>> Decimal('3.1415926535') + Decimal('2.7182818285')
+ Decimal("5.85987")
+ >>> getcontext().rounding = ROUND_UP
+ >>> Decimal('3.1415926535') + Decimal('2.7182818285')
+ Decimal("5.85988")
+
+Decimals interact well with much of the rest of Python. Here is a small decimal
+floating point flying circus::
+
+ >>> data = map(Decimal, '1.34 1.87 3.45 2.35 1.00 0.03 9.25'.split())
+ >>> max(data)
+ Decimal("9.25")
+ >>> min(data)
+ Decimal("0.03")
+ >>> sorted(data)
+ [Decimal("0.03"), Decimal("1.00"), Decimal("1.34"), Decimal("1.87"),
+ Decimal("2.35"), Decimal("3.45"), Decimal("9.25")]
+ >>> sum(data)
+ Decimal("19.29")
+ >>> a,b,c = data[:3]
+ >>> str(a)
+ '1.34'
+ >>> float(a)
+ 1.3400000000000001
+ >>> round(a, 1) # round() first converts to binary floating point
+ 1.3
+ >>> int(a)
+ 1
+ >>> a * 5
+ Decimal("6.70")
+ >>> a * b
+ Decimal("2.5058")
+ >>> c % a
+ Decimal("0.77")
+
+The :meth:`quantize` method rounds a number to a fixed exponent. This method is
+useful for monetary applications that often round results to a fixed number of
+places::
+
+ >>> Decimal('7.325').quantize(Decimal('.01'), rounding=ROUND_DOWN)
+ Decimal("7.32")
+ >>> Decimal('7.325').quantize(Decimal('1.'), rounding=ROUND_UP)
+ Decimal("8")
+
+As shown above, the :func:`getcontext` function accesses the current context and
+allows the settings to be changed. This approach meets the needs of most
+applications.
+
+For more advanced work, it may be useful to create alternate contexts using the
+Context() constructor. To make an alternate active, use the :func:`setcontext`
+function.
+
+In accordance with the standard, the :mod:`Decimal` module provides two ready to
+use standard contexts, :const:`BasicContext` and :const:`ExtendedContext`. The
+former is especially useful for debugging because many of the traps are
+enabled::
+
+ >>> myothercontext = Context(prec=60, rounding=ROUND_HALF_DOWN)
+ >>> setcontext(myothercontext)
+ >>> Decimal(1) / Decimal(7)
+ Decimal("0.142857142857142857142857142857142857142857142857142857142857")
+
+ >>> ExtendedContext
+ Context(prec=9, rounding=ROUND_HALF_EVEN, Emin=-999999999, Emax=999999999,
+ capitals=1, flags=[], traps=[])
+ >>> setcontext(ExtendedContext)
+ >>> Decimal(1) / Decimal(7)
+ Decimal("0.142857143")
+ >>> Decimal(42) / Decimal(0)
+ Decimal("Infinity")
+
+ >>> setcontext(BasicContext)
+ >>> Decimal(42) / Decimal(0)
+ Traceback (most recent call last):
+ File "<pyshell#143>", line 1, in -toplevel-
+ Decimal(42) / Decimal(0)
+ DivisionByZero: x / 0
+
+Contexts also have signal flags for monitoring exceptional conditions
+encountered during computations. The flags remain set until explicitly cleared,
+so it is best to clear the flags before each set of monitored computations by
+using the :meth:`clear_flags` method. ::
+
+ >>> setcontext(ExtendedContext)
+ >>> getcontext().clear_flags()
+ >>> Decimal(355) / Decimal(113)
+ Decimal("3.14159292")
+ >>> getcontext()
+ Context(prec=9, rounding=ROUND_HALF_EVEN, Emin=-999999999, Emax=999999999,
+ capitals=1, flags=[Inexact, Rounded], traps=[])
+
+The *flags* entry shows that the rational approximation to :const:`Pi` was
+rounded (digits beyond the context precision were thrown away) and that the
+result is inexact (some of the discarded digits were non-zero).
+
+Individual traps are set using the dictionary in the :attr:`traps` field of a
+context::
+
+ >>> Decimal(1) / Decimal(0)
+ Decimal("Infinity")
+ >>> getcontext().traps[DivisionByZero] = 1
+ >>> Decimal(1) / Decimal(0)
+ Traceback (most recent call last):
+ File "<pyshell#112>", line 1, in -toplevel-
+ Decimal(1) / Decimal(0)
+ DivisionByZero: x / 0
+
+Most programs adjust the current context only once, at the beginning of the
+program. And, in many applications, data is converted to :class:`Decimal` with
+a single cast inside a loop. With context set and decimals created, the bulk of
+the program manipulates the data no differently than with other Python numeric
+types.
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-decimal:
+
+Decimal objects
+---------------
+
+
+.. class:: Decimal([value [, context]])
+
+ Constructs a new :class:`Decimal` object based from *value*.
+
+ *value* can be an integer, string, tuple, or another :class:`Decimal` object. If
+ no *value* is given, returns ``Decimal("0")``. If *value* is a string, it
+ should conform to the decimal numeric string syntax::
+
+ sign ::= '+' | '-'
+ digit ::= '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
+ indicator ::= 'e' | 'E'
+ digits ::= digit [digit]...
+ decimal-part ::= digits '.' [digits] | ['.'] digits
+ exponent-part ::= indicator [sign] digits
+ infinity ::= 'Infinity' | 'Inf'
+ nan ::= 'NaN' [digits] | 'sNaN' [digits]
+ numeric-value ::= decimal-part [exponent-part] | infinity
+ numeric-string ::= [sign] numeric-value | [sign] nan
+
+ If *value* is a :class:`tuple`, it should have three components, a sign
+ (:const:`0` for positive or :const:`1` for negative), a :class:`tuple` of
+ digits, and an integer exponent. For example, ``Decimal((0, (1, 4, 1, 4), -3))``
+ returns ``Decimal("1.414")``.
+
+ The *context* precision does not affect how many digits are stored. That is
+ determined exclusively by the number of digits in *value*. For example,
+ ``Decimal("3.00000")`` records all five zeroes even if the context precision is
+ only three.
+
+ The purpose of the *context* argument is determining what to do if *value* is a
+ malformed string. If the context traps :const:`InvalidOperation`, an exception
+ is raised; otherwise, the constructor returns a new Decimal with the value of
+ :const:`NaN`.
+
+ Once constructed, :class:`Decimal` objects are immutable.
+
+Decimal floating point objects share many properties with the other builtin
+numeric types such as :class:`float` and :class:`int`. All of the usual math
+operations and special methods apply. Likewise, decimal objects can be copied,
+pickled, printed, used as dictionary keys, used as set elements, compared,
+sorted, and coerced to another type (such as :class:`float` or :class:`long`).
+
+In addition to the standard numeric properties, decimal floating point objects
+also have a number of specialized methods:
+
+
+.. method:: Decimal.adjusted()
+
+ Return the adjusted exponent after shifting out the coefficient's rightmost
+ digits until only the lead digit remains: ``Decimal("321e+5").adjusted()``
+ returns seven. Used for determining the position of the most significant digit
+ with respect to the decimal point.
+
+
+.. method:: Decimal.as_tuple()
+
+ Returns a tuple representation of the number: ``(sign, digittuple, exponent)``.
+
+
+.. method:: Decimal.compare(other[, context])
+
+ Compares like :meth:`__cmp__` but returns a decimal instance::
+
+ a or b is a NaN ==> Decimal("NaN")
+ a < b ==> Decimal("-1")
+ a == b ==> Decimal("0")
+ a > b ==> Decimal("1")
+
+
+.. method:: Decimal.max(other[, context])
+
+ Like ``max(self, other)`` except that the context rounding rule is applied
+ before returning and that :const:`NaN` values are either signalled or ignored
+ (depending on the context and whether they are signaling or quiet).
+
+
+.. method:: Decimal.min(other[, context])
+
+ Like ``min(self, other)`` except that the context rounding rule is applied
+ before returning and that :const:`NaN` values are either signalled or ignored
+ (depending on the context and whether they are signaling or quiet).
+
+
+.. method:: Decimal.normalize([context])
+
+ Normalize the number by stripping the rightmost trailing zeroes and converting
+ any result equal to :const:`Decimal("0")` to :const:`Decimal("0e0")`. Used for
+ producing canonical values for members of an equivalence class. For example,
+ ``Decimal("32.100")`` and ``Decimal("0.321000e+2")`` both normalize to the
+ equivalent value ``Decimal("32.1")``.
+
+
+.. method:: Decimal.quantize(exp [, rounding[, context[, watchexp]]])
+
+ Quantize makes the exponent the same as *exp*. Searches for a rounding method
+ in *rounding*, then in *context*, and then in the current context.
+
+ If *watchexp* is set (default), then an error is returned whenever the resulting
+ exponent is greater than :attr:`Emax` or less than :attr:`Etiny`.
+
+
+.. method:: Decimal.remainder_near(other[, context])
+
+ Computes the modulo as either a positive or negative value depending on which is
+ closest to zero. For instance, ``Decimal(10).remainder_near(6)`` returns
+ ``Decimal("-2")`` which is closer to zero than ``Decimal("4")``.
+
+ If both are equally close, the one chosen will have the same sign as *self*.
+
+
+.. method:: Decimal.same_quantum(other[, context])
+
+ Test whether self and other have the same exponent or whether both are
+ :const:`NaN`.
+
+
+.. method:: Decimal.sqrt([context])
+
+ Return the square root to full precision.
+
+
+.. method:: Decimal.to_eng_string([context])
+
+ Convert to an engineering-type string.
+
+ Engineering notation has an exponent which is a multiple of 3, so there are up
+ to 3 digits left of the decimal place. For example, converts
+ ``Decimal('123E+1')`` to ``Decimal("1.23E+3")``
+
+
+.. method:: Decimal.to_integral([rounding[, context]])
+
+ Rounds to the nearest integer without signaling :const:`Inexact` or
+ :const:`Rounded`. If given, applies *rounding*; otherwise, uses the rounding
+ method in either the supplied *context* or the current context.
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-context:
+
+Context objects
+---------------
+
+Contexts are environments for arithmetic operations. They govern precision, set
+rules for rounding, determine which signals are treated as exceptions, and limit
+the range for exponents.
+
+Each thread has its own current context which is accessed or changed using the
+:func:`getcontext` and :func:`setcontext` functions:
+
+
+.. function:: getcontext()
+
+ Return the current context for the active thread.
+
+
+.. function:: setcontext(c)
+
+ Set the current context for the active thread to *c*.
+
+Beginning with Python 2.5, you can also use the :keyword:`with` statement and
+the :func:`localcontext` function to temporarily change the active context.
+
+
+.. function:: localcontext([c])
+
+ Return a context manager that will set the current context for the active thread
+ to a copy of *c* on entry to the with-statement and restore the previous context
+ when exiting the with-statement. If no context is specified, a copy of the
+ current context is used.
+
+ .. versionadded:: 2.5
+
+ For example, the following code sets the current decimal precision to 42 places,
+ performs a calculation, and then automatically restores the previous context::
+
+ from __future__ import with_statement
+ from decimal import localcontext
+
+ with localcontext() as ctx:
+ ctx.prec = 42 # Perform a high precision calculation
+ s = calculate_something()
+ s = +s # Round the final result back to the default precision
+
+New contexts can also be created using the :class:`Context` constructor
+described below. In addition, the module provides three pre-made contexts:
+
+
+.. class:: BasicContext
+
+ This is a standard context defined by the General Decimal Arithmetic
+ Specification. Precision is set to nine. Rounding is set to
+ :const:`ROUND_HALF_UP`. All flags are cleared. All traps are enabled (treated
+ as exceptions) except :const:`Inexact`, :const:`Rounded`, and
+ :const:`Subnormal`.
+
+ Because many of the traps are enabled, this context is useful for debugging.
+
+
+.. class:: ExtendedContext
+
+ This is a standard context defined by the General Decimal Arithmetic
+ Specification. Precision is set to nine. Rounding is set to
+ :const:`ROUND_HALF_EVEN`. All flags are cleared. No traps are enabled (so that
+ exceptions are not raised during computations).
+
+ Because the trapped are disabled, this context is useful for applications that
+ prefer to have result value of :const:`NaN` or :const:`Infinity` instead of
+ raising exceptions. This allows an application to complete a run in the
+ presence of conditions that would otherwise halt the program.
+
+
+.. class:: DefaultContext
+
+ This context is used by the :class:`Context` constructor as a prototype for new
+ contexts. Changing a field (such a precision) has the effect of changing the
+ default for new contexts creating by the :class:`Context` constructor.
+
+ This context is most useful in multi-threaded environments. Changing one of the
+ fields before threads are started has the effect of setting system-wide
+ defaults. Changing the fields after threads have started is not recommended as
+ it would require thread synchronization to prevent race conditions.
+
+ In single threaded environments, it is preferable to not use this context at
+ all. Instead, simply create contexts explicitly as described below.
+
+ The default values are precision=28, rounding=ROUND_HALF_EVEN, and enabled traps
+ for Overflow, InvalidOperation, and DivisionByZero.
+
+In addition to the three supplied contexts, new contexts can be created with the
+:class:`Context` constructor.
+
+
+.. class:: Context(prec=None, rounding=None, traps=None, flags=None, Emin=None, Emax=None, capitals=1)
+
+ Creates a new context. If a field is not specified or is :const:`None`, the
+ default values are copied from the :const:`DefaultContext`. If the *flags*
+ field is not specified or is :const:`None`, all flags are cleared.
+
+ The *prec* field is a positive integer that sets the precision for arithmetic
+ operations in the context.
+
+ The *rounding* option is one of:
+
+ * :const:`ROUND_CEILING` (towards :const:`Infinity`),
+ * :const:`ROUND_DOWN` (towards zero),
+ * :const:`ROUND_FLOOR` (towards :const:`-Infinity`),
+ * :const:`ROUND_HALF_DOWN` (to nearest with ties going towards zero),
+ * :const:`ROUND_HALF_EVEN` (to nearest with ties going to nearest even integer),
+ * :const:`ROUND_HALF_UP` (to nearest with ties going away from zero), or
+ * :const:`ROUND_UP` (away from zero).
+
+ The *traps* and *flags* fields list any signals to be set. Generally, new
+ contexts should only set traps and leave the flags clear.
+
+ The *Emin* and *Emax* fields are integers specifying the outer limits allowable
+ for exponents.
+
+ The *capitals* field is either :const:`0` or :const:`1` (the default). If set to
+ :const:`1`, exponents are printed with a capital :const:`E`; otherwise, a
+ lowercase :const:`e` is used: :const:`Decimal('6.02e+23')`.
+
+The :class:`Context` class defines several general purpose methods as well as a
+large number of methods for doing arithmetic directly in a given context.
+
+
+.. method:: Context.clear_flags()
+
+ Resets all of the flags to :const:`0`.
+
+
+.. method:: Context.copy()
+
+ Return a duplicate of the context.
+
+
+.. method:: Context.create_decimal(num)
+
+ Creates a new Decimal instance from *num* but using *self* as context. Unlike
+ the :class:`Decimal` constructor, the context precision, rounding method, flags,
+ and traps are applied to the conversion.
+
+ This is useful because constants are often given to a greater precision than is
+ needed by the application. Another benefit is that rounding immediately
+ eliminates unintended effects from digits beyond the current precision. In the
+ following example, using unrounded inputs means that adding zero to a sum can
+ change the result::
+
+ >>> getcontext().prec = 3
+ >>> Decimal("3.4445") + Decimal("1.0023")
+ Decimal("4.45")
+ >>> Decimal("3.4445") + Decimal(0) + Decimal("1.0023")
+ Decimal("4.44")
+
+
+.. method:: Context.Etiny()
+
+ Returns a value equal to ``Emin - prec + 1`` which is the minimum exponent value
+ for subnormal results. When underflow occurs, the exponent is set to
+ :const:`Etiny`.
+
+
+.. method:: Context.Etop()
+
+ Returns a value equal to ``Emax - prec + 1``.
+
+The usual approach to working with decimals is to create :class:`Decimal`
+instances and then apply arithmetic operations which take place within the
+current context for the active thread. An alternate approach is to use context
+methods for calculating within a specific context. The methods are similar to
+those for the :class:`Decimal` class and are only briefly recounted here.
+
+
+.. method:: Context.abs(x)
+
+ Returns the absolute value of *x*.
+
+
+.. method:: Context.add(x, y)
+
+ Return the sum of *x* and *y*.
+
+
+.. method:: Context.compare(x, y)
+
+ Compares values numerically.
+
+ Like :meth:`__cmp__` but returns a decimal instance::
+
+ a or b is a NaN ==> Decimal("NaN")
+ a < b ==> Decimal("-1")
+ a == b ==> Decimal("0")
+ a > b ==> Decimal("1")
+
+
+.. method:: Context.divide(x, y)
+
+ Return *x* divided by *y*.
+
+
+.. method:: Context.divmod(x, y)
+
+ Divides two numbers and returns the integer part of the result.
+
+
+.. method:: Context.max(x, y)
+
+ Compare two values numerically and return the maximum.
+
+ If they are numerically equal then the left-hand operand is chosen as the
+ result.
+
+
+.. method:: Context.min(x, y)
+
+ Compare two values numerically and return the minimum.
+
+ If they are numerically equal then the left-hand operand is chosen as the
+ result.
+
+
+.. method:: Context.minus(x)
+
+ Minus corresponds to the unary prefix minus operator in Python.
+
+
+.. method:: Context.multiply(x, y)
+
+ Return the product of *x* and *y*.
+
+
+.. method:: Context.normalize(x)
+
+ Normalize reduces an operand to its simplest form.
+
+ Essentially a :meth:`plus` operation with all trailing zeros removed from the
+ result.
+
+
+.. method:: Context.plus(x)
+
+ Plus corresponds to the unary prefix plus operator in Python. This operation
+ applies the context precision and rounding, so it is *not* an identity
+ operation.
+
+
+.. method:: Context.power(x, y[, modulo])
+
+ Return ``x ** y`` to the *modulo* if given.
+
+ The right-hand operand must be a whole number whose integer part (after any
+ exponent has been applied) has no more than 9 digits and whose fractional part
+ (if any) is all zeros before any rounding. The operand may be positive,
+ negative, or zero; if negative, the absolute value of the power is used, and the
+ left-hand operand is inverted (divided into 1) before use.
+
+ If the increased precision needed for the intermediate calculations exceeds the
+ capabilities of the implementation then an :const:`InvalidOperation` condition
+ is signaled.
+
+ If, when raising to a negative power, an underflow occurs during the division
+ into 1, the operation is not halted at that point but continues.
+
+
+.. method:: Context.quantize(x, y)
+
+ Returns a value equal to *x* after rounding and having the exponent of *y*.
+
+ Unlike other operations, if the length of the coefficient after the quantize
+ operation would be greater than precision, then an :const:`InvalidOperation` is
+ signaled. This guarantees that, unless there is an error condition, the
+ quantized exponent is always equal to that of the right-hand operand.
+
+ Also unlike other operations, quantize never signals Underflow, even if the
+ result is subnormal and inexact.
+
+
+.. method:: Context.remainder(x, y)
+
+ Returns the remainder from integer division.
+
+ The sign of the result, if non-zero, is the same as that of the original
+ dividend.
+
+
+.. method:: Context.remainder_near(x, y)
+
+ Computed the modulo as either a positive or negative value depending on which is
+ closest to zero. For instance, ``Decimal(10).remainder_near(6)`` returns
+ ``Decimal("-2")`` which is closer to zero than ``Decimal("4")``.
+
+ If both are equally close, the one chosen will have the same sign as *self*.
+
+
+.. method:: Context.same_quantum(x, y)
+
+ Test whether *x* and *y* have the same exponent or whether both are
+ :const:`NaN`.
+
+
+.. method:: Context.sqrt(x)
+
+ Return the square root of *x* to full precision.
+
+
+.. method:: Context.subtract(x, y)
+
+ Return the difference between *x* and *y*.
+
+
+.. method:: Context.to_eng_string()
+
+ Convert to engineering-type string.
+
+ Engineering notation has an exponent which is a multiple of 3, so there are up
+ to 3 digits left of the decimal place. For example, converts
+ ``Decimal('123E+1')`` to ``Decimal("1.23E+3")``
+
+
+.. method:: Context.to_integral(x)
+
+ Rounds to the nearest integer without signaling :const:`Inexact` or
+ :const:`Rounded`.
+
+
+.. method:: Context.to_sci_string(x)
+
+ Converts a number to a string using scientific notation.
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-signals:
+
+Signals
+-------
+
+Signals represent conditions that arise during computation. Each corresponds to
+one context flag and one context trap enabler.
+
+The context flag is incremented whenever the condition is encountered. After the
+computation, flags may be checked for informational purposes (for instance, to
+determine whether a computation was exact). After checking the flags, be sure to
+clear all flags before starting the next computation.
+
+If the context's trap enabler is set for the signal, then the condition causes a
+Python exception to be raised. For example, if the :class:`DivisionByZero` trap
+is set, then a :exc:`DivisionByZero` exception is raised upon encountering the
+condition.
+
+
+.. class:: Clamped
+
+ Altered an exponent to fit representation constraints.
+
+ Typically, clamping occurs when an exponent falls outside the context's
+ :attr:`Emin` and :attr:`Emax` limits. If possible, the exponent is reduced to
+ fit by adding zeroes to the coefficient.
+
+
+.. class:: DecimalException
+
+ Base class for other signals and a subclass of :exc:`ArithmeticError`.
+
+
+.. class:: DivisionByZero
+
+ Signals the division of a non-infinite number by zero.
+
+ Can occur with division, modulo division, or when raising a number to a negative
+ power. If this signal is not trapped, returns :const:`Infinity` or
+ :const:`-Infinity` with the sign determined by the inputs to the calculation.
+
+
+.. class:: Inexact
+
+ Indicates that rounding occurred and the result is not exact.
+
+ Signals when non-zero digits were discarded during rounding. The rounded result
+ is returned. The signal flag or trap is used to detect when results are
+ inexact.
+
+
+.. class:: InvalidOperation
+
+ An invalid operation was performed.
+
+ Indicates that an operation was requested that does not make sense. If not
+ trapped, returns :const:`NaN`. Possible causes include::
+
+ Infinity - Infinity
+ 0 * Infinity
+ Infinity / Infinity
+ x % 0
+ Infinity % x
+ x._rescale( non-integer )
+ sqrt(-x) and x > 0
+ 0 ** 0
+ x ** (non-integer)
+ x ** Infinity
+
+
+.. class:: Overflow
+
+ Numerical overflow.
+
+ Indicates the exponent is larger than :attr:`Emax` after rounding has occurred.
+ If not trapped, the result depends on the rounding mode, either pulling inward
+ to the largest representable finite number or rounding outward to
+ :const:`Infinity`. In either case, :class:`Inexact` and :class:`Rounded` are
+ also signaled.
+
+
+.. class:: Rounded
+
+ Rounding occurred though possibly no information was lost.
+
+ Signaled whenever rounding discards digits; even if those digits are zero (such
+ as rounding :const:`5.00` to :const:`5.0`). If not trapped, returns the result
+ unchanged. This signal is used to detect loss of significant digits.
+
+
+.. class:: Subnormal
+
+ Exponent was lower than :attr:`Emin` prior to rounding.
+
+ Occurs when an operation result is subnormal (the exponent is too small). If not
+ trapped, returns the result unchanged.
+
+
+.. class:: Underflow
+
+ Numerical underflow with result rounded to zero.
+
+ Occurs when a subnormal result is pushed to zero by rounding. :class:`Inexact`
+ and :class:`Subnormal` are also signaled.
+
+The following table summarizes the hierarchy of signals::
+
+ exceptions.ArithmeticError(exceptions.Exception)
+ DecimalException
+ Clamped
+ DivisionByZero(DecimalException, exceptions.ZeroDivisionError)
+ Inexact
+ Overflow(Inexact, Rounded)
+ Underflow(Inexact, Rounded, Subnormal)
+ InvalidOperation
+ Rounded
+ Subnormal
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-notes:
+
+Floating Point Notes
+--------------------
+
+
+Mitigating round-off error with increased precision
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The use of decimal floating point eliminates decimal representation error
+(making it possible to represent :const:`0.1` exactly); however, some operations
+can still incur round-off error when non-zero digits exceed the fixed precision.
+
+The effects of round-off error can be amplified by the addition or subtraction
+of nearly offsetting quantities resulting in loss of significance. Knuth
+provides two instructive examples where rounded floating point arithmetic with
+insufficient precision causes the breakdown of the associative and distributive
+properties of addition::
+
+ # Examples from Seminumerical Algorithms, Section 4.2.2.
+ >>> from decimal import Decimal, getcontext
+ >>> getcontext().prec = 8
+
+ >>> u, v, w = Decimal(11111113), Decimal(-11111111), Decimal('7.51111111')
+ >>> (u + v) + w
+ Decimal("9.5111111")
+ >>> u + (v + w)
+ Decimal("10")
+
+ >>> u, v, w = Decimal(20000), Decimal(-6), Decimal('6.0000003')
+ >>> (u*v) + (u*w)
+ Decimal("0.01")
+ >>> u * (v+w)
+ Decimal("0.0060000")
+
+The :mod:`decimal` module makes it possible to restore the identities by
+expanding the precision sufficiently to avoid loss of significance::
+
+ >>> getcontext().prec = 20
+ >>> u, v, w = Decimal(11111113), Decimal(-11111111), Decimal('7.51111111')
+ >>> (u + v) + w
+ Decimal("9.51111111")
+ >>> u + (v + w)
+ Decimal("9.51111111")
+ >>>
+ >>> u, v, w = Decimal(20000), Decimal(-6), Decimal('6.0000003')
+ >>> (u*v) + (u*w)
+ Decimal("0.0060000")
+ >>> u * (v+w)
+ Decimal("0.0060000")
+
+
+Special values
+^^^^^^^^^^^^^^
+
+The number system for the :mod:`decimal` module provides special values
+including :const:`NaN`, :const:`sNaN`, :const:`-Infinity`, :const:`Infinity`,
+and two zeroes, :const:`+0` and :const:`-0`.
+
+Infinities can be constructed directly with: ``Decimal('Infinity')``. Also,
+they can arise from dividing by zero when the :exc:`DivisionByZero` signal is
+not trapped. Likewise, when the :exc:`Overflow` signal is not trapped, infinity
+can result from rounding beyond the limits of the largest representable number.
+
+The infinities are signed (affine) and can be used in arithmetic operations
+where they get treated as very large, indeterminate numbers. For instance,
+adding a constant to infinity gives another infinite result.
+
+Some operations are indeterminate and return :const:`NaN`, or if the
+:exc:`InvalidOperation` signal is trapped, raise an exception. For example,
+``0/0`` returns :const:`NaN` which means "not a number". This variety of
+:const:`NaN` is quiet and, once created, will flow through other computations
+always resulting in another :const:`NaN`. This behavior can be useful for a
+series of computations that occasionally have missing inputs --- it allows the
+calculation to proceed while flagging specific results as invalid.
+
+A variant is :const:`sNaN` which signals rather than remaining quiet after every
+operation. This is a useful return value when an invalid result needs to
+interrupt a calculation for special handling.
+
+The signed zeros can result from calculations that underflow. They keep the sign
+that would have resulted if the calculation had been carried out to greater
+precision. Since their magnitude is zero, both positive and negative zeros are
+treated as equal and their sign is informational.
+
+In addition to the two signed zeros which are distinct yet equal, there are
+various representations of zero with differing precisions yet equivalent in
+value. This takes a bit of getting used to. For an eye accustomed to
+normalized floating point representations, it is not immediately obvious that
+the following calculation returns a value equal to zero::
+
+ >>> 1 / Decimal('Infinity')
+ Decimal("0E-1000000026")
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-threads:
+
+Working with threads
+--------------------
+
+The :func:`getcontext` function accesses a different :class:`Context` object for
+each thread. Having separate thread contexts means that threads may make
+changes (such as ``getcontext.prec=10``) without interfering with other threads.
+
+Likewise, the :func:`setcontext` function automatically assigns its target to
+the current thread.
+
+If :func:`setcontext` has not been called before :func:`getcontext`, then
+:func:`getcontext` will automatically create a new context for use in the
+current thread.
+
+The new context is copied from a prototype context called *DefaultContext*. To
+control the defaults so that each thread will use the same values throughout the
+application, directly modify the *DefaultContext* object. This should be done
+*before* any threads are started so that there won't be a race condition between
+threads calling :func:`getcontext`. For example::
+
+ # Set applicationwide defaults for all threads about to be launched
+ DefaultContext.prec = 12
+ DefaultContext.rounding = ROUND_DOWN
+ DefaultContext.traps = ExtendedContext.traps.copy()
+ DefaultContext.traps[InvalidOperation] = 1
+ setcontext(DefaultContext)
+
+ # Afterwards, the threads can be started
+ t1.start()
+ t2.start()
+ t3.start()
+ . . .
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-recipes:
+
+Recipes
+-------
+
+Here are a few recipes that serve as utility functions and that demonstrate ways
+to work with the :class:`Decimal` class::
+
+ def moneyfmt(value, places=2, curr='', sep=',', dp='.',
+ pos='', neg='-', trailneg=''):
+ """Convert Decimal to a money formatted string.
+
+ places: required number of places after the decimal point
+ curr: optional currency symbol before the sign (may be blank)
+ sep: optional grouping separator (comma, period, space, or blank)
+ dp: decimal point indicator (comma or period)
+ only specify as blank when places is zero
+ pos: optional sign for positive numbers: '+', space or blank
+ neg: optional sign for negative numbers: '-', '(', space or blank
+ trailneg:optional trailing minus indicator: '-', ')', space or blank
+
+ >>> d = Decimal('-1234567.8901')
+ >>> moneyfmt(d, curr='$')
+ '-$1,234,567.89'
+ >>> moneyfmt(d, places=0, sep='.', dp='', neg='', trailneg='-')
+ '1.234.568-'
+ >>> moneyfmt(d, curr='$', neg='(', trailneg=')')
+ '($1,234,567.89)'
+ >>> moneyfmt(Decimal(123456789), sep=' ')
+ '123 456 789.00'
+ >>> moneyfmt(Decimal('-0.02'), neg='<', trailneg='>')
+ '<.02>'
+
+ """
+ q = Decimal((0, (1,), -places)) # 2 places --> '0.01'
+ sign, digits, exp = value.quantize(q).as_tuple()
+ assert exp == -places
+ result = []
+ digits = map(str, digits)
+ build, next = result.append, digits.pop
+ if sign:
+ build(trailneg)
+ for i in range(places):
+ if digits:
+ build(next())
+ else:
+ build('0')
+ build(dp)
+ i = 0
+ while digits:
+ build(next())
+ i += 1
+ if i == 3 and digits:
+ i = 0
+ build(sep)
+ build(curr)
+ if sign:
+ build(neg)
+ else:
+ build(pos)
+ result.reverse()
+ return ''.join(result)
+
+ def pi():
+ """Compute Pi to the current precision.
+
+ >>> print pi()
+ 3.141592653589793238462643383
+
+ """
+ getcontext().prec += 2 # extra digits for intermediate steps
+ three = Decimal(3) # substitute "three=3.0" for regular floats
+ lasts, t, s, n, na, d, da = 0, three, 3, 1, 0, 0, 24
+ while s != lasts:
+ lasts = s
+ n, na = n+na, na+8
+ d, da = d+da, da+32
+ t = (t * n) / d
+ s += t
+ getcontext().prec -= 2
+ return +s # unary plus applies the new precision
+
+ def exp(x):
+ """Return e raised to the power of x. Result type matches input type.
+
+ >>> print exp(Decimal(1))
+ 2.718281828459045235360287471
+ >>> print exp(Decimal(2))
+ 7.389056098930650227230427461
+ >>> print exp(2.0)
+ 7.38905609893
+ >>> print exp(2+0j)
+ (7.38905609893+0j)
+
+ """
+ getcontext().prec += 2
+ i, lasts, s, fact, num = 0, 0, 1, 1, 1
+ while s != lasts:
+ lasts = s
+ i += 1
+ fact *= i
+ num *= x
+ s += num / fact
+ getcontext().prec -= 2
+ return +s
+
+ def cos(x):
+ """Return the cosine of x as measured in radians.
+
+ >>> print cos(Decimal('0.5'))
+ 0.8775825618903727161162815826
+ >>> print cos(0.5)
+ 0.87758256189
+ >>> print cos(0.5+0j)
+ (0.87758256189+0j)
+
+ """
+ getcontext().prec += 2
+ i, lasts, s, fact, num, sign = 0, 0, 1, 1, 1, 1
+ while s != lasts:
+ lasts = s
+ i += 2
+ fact *= i * (i-1)
+ num *= x * x
+ sign *= -1
+ s += num / fact * sign
+ getcontext().prec -= 2
+ return +s
+
+ def sin(x):
+ """Return the sine of x as measured in radians.
+
+ >>> print sin(Decimal('0.5'))
+ 0.4794255386042030002732879352
+ >>> print sin(0.5)
+ 0.479425538604
+ >>> print sin(0.5+0j)
+ (0.479425538604+0j)
+
+ """
+ getcontext().prec += 2
+ i, lasts, s, fact, num, sign = 1, 0, x, 1, x, 1
+ while s != lasts:
+ lasts = s
+ i += 2
+ fact *= i * (i-1)
+ num *= x * x
+ sign *= -1
+ s += num / fact * sign
+ getcontext().prec -= 2
+ return +s
+
+
+.. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+.. _decimal-faq:
+
+Decimal FAQ
+-----------
+
+Q. It is cumbersome to type ``decimal.Decimal('1234.5')``. Is there a way to
+minimize typing when using the interactive interpreter?
+
+\A. Some users abbreviate the constructor to just a single letter::
+
+ >>> D = decimal.Decimal
+ >>> D('1.23') + D('3.45')
+ Decimal("4.68")
+
+Q. In a fixed-point application with two decimal places, some inputs have many
+places and need to be rounded. Others are not supposed to have excess digits
+and need to be validated. What methods should be used?
+
+A. The :meth:`quantize` method rounds to a fixed number of decimal places. If
+the :const:`Inexact` trap is set, it is also useful for validation::
+
+ >>> TWOPLACES = Decimal(10) ** -2 # same as Decimal('0.01')
+
+ >>> # Round to two places
+ >>> Decimal("3.214").quantize(TWOPLACES)
+ Decimal("3.21")
+
+ >>> # Validate that a number does not exceed two places
+ >>> Decimal("3.21").quantize(TWOPLACES, context=Context(traps=[Inexact]))
+ Decimal("3.21")
+
+ >>> Decimal("3.214").quantize(TWOPLACES, context=Context(traps=[Inexact]))
+ Traceback (most recent call last):
+ ...
+ Inexact: Changed in rounding
+
+Q. Once I have valid two place inputs, how do I maintain that invariant
+throughout an application?
+
+A. Some operations like addition and subtraction automatically preserve fixed
+point. Others, like multiplication and division, change the number of decimal
+places and need to be followed-up with a :meth:`quantize` step.
+
+Q. There are many ways to express the same value. The numbers :const:`200`,
+:const:`200.000`, :const:`2E2`, and :const:`.02E+4` all have the same value at
+various precisions. Is there a way to transform them to a single recognizable
+canonical value?
+
+A. The :meth:`normalize` method maps all equivalent values to a single
+representative::
+
+ >>> values = map(Decimal, '200 200.000 2E2 .02E+4'.split())
+ >>> [v.normalize() for v in values]
+ [Decimal("2E+2"), Decimal("2E+2"), Decimal("2E+2"), Decimal("2E+2")]
+
+Q. Some decimal values always print with exponential notation. Is there a way
+to get a non-exponential representation?
+
+A. For some values, exponential notation is the only way to express the number
+of significant places in the coefficient. For example, expressing
+:const:`5.0E+3` as :const:`5000` keeps the value constant but cannot show the
+original's two-place significance.
+
+Q. Is there a way to convert a regular float to a :class:`Decimal`?
+
+A. Yes, all binary floating point numbers can be exactly expressed as a
+Decimal. An exact conversion may take more precision than intuition would
+suggest, so trapping :const:`Inexact` will signal a need for more precision::
+
+ def floatToDecimal(f):
+ "Convert a floating point number to a Decimal with no loss of information"
+ # Transform (exactly) a float to a mantissa (0.5 <= abs(m) < 1.0) and an
+ # exponent. Double the mantissa until it is an integer. Use the integer
+ # mantissa and exponent to compute an equivalent Decimal. If this cannot
+ # be done exactly, then retry with more precision.
+
+ mantissa, exponent = math.frexp(f)
+ while mantissa != int(mantissa):
+ mantissa *= 2.0
+ exponent -= 1
+ mantissa = int(mantissa)
+
+ oldcontext = getcontext()
+ setcontext(Context(traps=[Inexact]))
+ try:
+ while True:
+ try:
+ return mantissa * Decimal(2) ** exponent
+ except Inexact:
+ getcontext().prec += 1
+ finally:
+ setcontext(oldcontext)
+
+Q. Why isn't the :func:`floatToDecimal` routine included in the module?
+
+A. There is some question about whether it is advisable to mix binary and
+decimal floating point. Also, its use requires some care to avoid the
+representation issues associated with binary floating point::
+
+ >>> floatToDecimal(1.1)
+ Decimal("1.100000000000000088817841970012523233890533447265625")
+
+Q. Within a complex calculation, how can I make sure that I haven't gotten a
+spurious result because of insufficient precision or rounding anomalies.
+
+A. The decimal module makes it easy to test results. A best practice is to
+re-run calculations using greater precision and with various rounding modes.
+Widely differing results indicate insufficient precision, rounding mode issues,
+ill-conditioned inputs, or a numerically unstable algorithm.
+
+Q. I noticed that context precision is applied to the results of operations but
+not to the inputs. Is there anything to watch out for when mixing values of
+different precisions?
+
+A. Yes. The principle is that all values are considered to be exact and so is
+the arithmetic on those values. Only the results are rounded. The advantage
+for inputs is that "what you type is what you get". A disadvantage is that the
+results can look odd if you forget that the inputs haven't been rounded::
+
+ >>> getcontext().prec = 3
+ >>> Decimal('3.104') + D('2.104')
+ Decimal("5.21")
+ >>> Decimal('3.104') + D('0.000') + D('2.104')
+ Decimal("5.20")
+
+The solution is either to increase precision or to force rounding of inputs
+using the unary plus operation::
+
+ >>> getcontext().prec = 3
+ >>> +Decimal('1.23456789') # unary plus triggers rounding
+ Decimal("1.23")
+
+Alternatively, inputs can be rounded upon creation using the
+:meth:`Context.create_decimal` method::
+
+ >>> Context(prec=5, rounding=ROUND_DOWN).create_decimal('1.2345678')
+ Decimal("1.2345")
+
diff --git a/Doc/library/development.rst b/Doc/library/development.rst
new file mode 100644
index 0000000000..be8c33d8e7
--- /dev/null
+++ b/Doc/library/development.rst
@@ -0,0 +1,22 @@
+
+.. _development:
+
+*****************
+Development Tools
+*****************
+
+The modules described in this chapter help you write software. For example, the
+:mod:`pydoc` module takes a module and generates documentation based on the
+module's contents. The :mod:`doctest` and :mod:`unittest` modules contains
+frameworks for writing unit tests that automatically exercise code and verify
+that the expected output is produced.
+
+The list of modules described in this chapter is:
+
+
+.. toctree::
+
+ pydoc.rst
+ doctest.rst
+ unittest.rst
+ test.rst
diff --git a/Doc/library/difflib.rst b/Doc/library/difflib.rst
new file mode 100644
index 0000000000..95b83e63d5
--- /dev/null
+++ b/Doc/library/difflib.rst
@@ -0,0 +1,644 @@
+
+:mod:`difflib` --- Helpers for computing deltas
+===============================================
+
+.. module:: difflib
+ :synopsis: Helpers for computing differences between objects.
+.. moduleauthor:: Tim Peters <tim_one@users.sourceforge.net>
+.. sectionauthor:: Tim Peters <tim_one@users.sourceforge.net>
+
+
+.. % LaTeXification by Fred L. Drake, Jr. <fdrake@acm.org>.
+
+.. versionadded:: 2.1
+
+
+.. class:: SequenceMatcher
+
+ This is a flexible class for comparing pairs of sequences of any type, so long
+ as the sequence elements are hashable. The basic algorithm predates, and is a
+ little fancier than, an algorithm published in the late 1980's by Ratcliff and
+ Obershelp under the hyperbolic name "gestalt pattern matching." The idea is to
+ find the longest contiguous matching subsequence that contains no "junk"
+ elements (the Ratcliff and Obershelp algorithm doesn't address junk). The same
+ idea is then applied recursively to the pieces of the sequences to the left and
+ to the right of the matching subsequence. This does not yield minimal edit
+ sequences, but does tend to yield matches that "look right" to people.
+
+ **Timing:** The basic Ratcliff-Obershelp algorithm is cubic time in the worst
+ case and quadratic time in the expected case. :class:`SequenceMatcher` is
+ quadratic time for the worst case and has expected-case behavior dependent in a
+ complicated way on how many elements the sequences have in common; best case
+ time is linear.
+
+
+.. class:: Differ
+
+ This is a class for comparing sequences of lines of text, and producing
+ human-readable differences or deltas. Differ uses :class:`SequenceMatcher`
+ both to compare sequences of lines, and to compare sequences of characters
+ within similar (near-matching) lines.
+
+ Each line of a :class:`Differ` delta begins with a two-letter code:
+
+ +----------+-------------------------------------------+
+ | Code | Meaning |
+ +==========+===========================================+
+ | ``'- '`` | line unique to sequence 1 |
+ +----------+-------------------------------------------+
+ | ``'+ '`` | line unique to sequence 2 |
+ +----------+-------------------------------------------+
+ | ``' '`` | line common to both sequences |
+ +----------+-------------------------------------------+
+ | ``'? '`` | line not present in either input sequence |
+ +----------+-------------------------------------------+
+
+ Lines beginning with '``?``' attempt to guide the eye to intraline differences,
+ and were not present in either input sequence. These lines can be confusing if
+ the sequences contain tab characters.
+
+
+.. class:: HtmlDiff
+
+ This class can be used to create an HTML table (or a complete HTML file
+ containing the table) showing a side by side, line by line comparison of text
+ with inter-line and intra-line change highlights. The table can be generated in
+ either full or contextual difference mode.
+
+ The constructor for this class is:
+
+
+ .. function:: __init__([tabsize][, wrapcolumn][, linejunk][, charjunk])
+
+ Initializes instance of :class:`HtmlDiff`.
+
+ *tabsize* is an optional keyword argument to specify tab stop spacing and
+ defaults to ``8``.
+
+ *wrapcolumn* is an optional keyword to specify column number where lines are
+ broken and wrapped, defaults to ``None`` where lines are not wrapped.
+
+ *linejunk* and *charjunk* are optional keyword arguments passed into ``ndiff()``
+ (used by :class:`HtmlDiff` to generate the side by side HTML differences). See
+ ``ndiff()`` documentation for argument default values and descriptions.
+
+ The following methods are public:
+
+
+ .. function:: make_file(fromlines, tolines [, fromdesc][, todesc][, context][, numlines])
+
+ Compares *fromlines* and *tolines* (lists of strings) and returns a string which
+ is a complete HTML file containing a table showing line by line differences with
+ inter-line and intra-line changes highlighted.
+
+ *fromdesc* and *todesc* are optional keyword arguments to specify from/to file
+ column header strings (both default to an empty string).
+
+ *context* and *numlines* are both optional keyword arguments. Set *context* to
+ ``True`` when contextual differences are to be shown, else the default is
+ ``False`` to show the full files. *numlines* defaults to ``5``. When *context*
+ is ``True`` *numlines* controls the number of context lines which surround the
+ difference highlights. When *context* is ``False`` *numlines* controls the
+ number of lines which are shown before a difference highlight when using the
+ "next" hyperlinks (setting to zero would cause the "next" hyperlinks to place
+ the next difference highlight at the top of the browser without any leading
+ context).
+
+
+ .. function:: make_table(fromlines, tolines [, fromdesc][, todesc][, context][, numlines])
+
+ Compares *fromlines* and *tolines* (lists of strings) and returns a string which
+ is a complete HTML table showing line by line differences with inter-line and
+ intra-line changes highlighted.
+
+ The arguments for this method are the same as those for the :meth:`make_file`
+ method.
+
+ :file:`Tools/scripts/diff.py` is a command-line front-end to this class and
+ contains a good example of its use.
+
+ .. versionadded:: 2.4
+
+
+.. function:: context_diff(a, b[, fromfile][, tofile][, fromfiledate][, tofiledate][, n][, lineterm])
+
+ Compare *a* and *b* (lists of strings); return a delta (a generator generating
+ the delta lines) in context diff format.
+
+ Context diffs are a compact way of showing just the lines that have changed plus
+ a few lines of context. The changes are shown in a before/after style. The
+ number of context lines is set by *n* which defaults to three.
+
+ By default, the diff control lines (those with ``***`` or ``---``) are created
+ with a trailing newline. This is helpful so that inputs created from
+ :func:`file.readlines` result in diffs that are suitable for use with
+ :func:`file.writelines` since both the inputs and outputs have trailing
+ newlines.
+
+ For inputs that do not have trailing newlines, set the *lineterm* argument to
+ ``""`` so that the output will be uniformly newline free.
+
+ The context diff format normally has a header for filenames and modification
+ times. Any or all of these may be specified using strings for *fromfile*,
+ *tofile*, *fromfiledate*, and *tofiledate*. The modification times are normally
+ expressed in the format returned by :func:`time.ctime`. If not specified, the
+ strings default to blanks.
+
+ :file:`Tools/scripts/diff.py` is a command-line front-end for this function.
+
+ .. versionadded:: 2.3
+
+
+.. function:: get_close_matches(word, possibilities[, n][, cutoff])
+
+ Return a list of the best "good enough" matches. *word* is a sequence for which
+ close matches are desired (typically a string), and *possibilities* is a list of
+ sequences against which to match *word* (typically a list of strings).
+
+ Optional argument *n* (default ``3``) is the maximum number of close matches to
+ return; *n* must be greater than ``0``.
+
+ Optional argument *cutoff* (default ``0.6``) is a float in the range [0, 1].
+ Possibilities that don't score at least that similar to *word* are ignored.
+
+ The best (no more than *n*) matches among the possibilities are returned in a
+ list, sorted by similarity score, most similar first. ::
+
+ >>> get_close_matches('appel', ['ape', 'apple', 'peach', 'puppy'])
+ ['apple', 'ape']
+ >>> import keyword
+ >>> get_close_matches('wheel', keyword.kwlist)
+ ['while']
+ >>> get_close_matches('apple', keyword.kwlist)
+ []
+ >>> get_close_matches('accept', keyword.kwlist)
+ ['except']
+
+
+.. function:: ndiff(a, b[, linejunk][, charjunk])
+
+ Compare *a* and *b* (lists of strings); return a :class:`Differ`\ -style delta
+ (a generator generating the delta lines).
+
+ Optional keyword parameters *linejunk* and *charjunk* are for filter functions
+ (or ``None``):
+
+ *linejunk*: A function that accepts a single string argument, and returns true
+ if the string is junk, or false if not. The default is (``None``), starting with
+ Python 2.3. Before then, the default was the module-level function
+ :func:`IS_LINE_JUNK`, which filters out lines without visible characters, except
+ for at most one pound character (``'#'``). As of Python 2.3, the underlying
+ :class:`SequenceMatcher` class does a dynamic analysis of which lines are so
+ frequent as to constitute noise, and this usually works better than the pre-2.3
+ default.
+
+ *charjunk*: A function that accepts a character (a string of length 1), and
+ returns if the character is junk, or false if not. The default is module-level
+ function :func:`IS_CHARACTER_JUNK`, which filters out whitespace characters (a
+ blank or tab; note: bad idea to include newline in this!).
+
+ :file:`Tools/scripts/ndiff.py` is a command-line front-end to this function. ::
+
+ >>> diff = ndiff('one\ntwo\nthree\n'.splitlines(1),
+ ... 'ore\ntree\nemu\n'.splitlines(1))
+ >>> print ''.join(diff),
+ - one
+ ? ^
+ + ore
+ ? ^
+ - two
+ - three
+ ? -
+ + tree
+ + emu
+
+
+.. function:: restore(sequence, which)
+
+ Return one of the two sequences that generated a delta.
+
+ Given a *sequence* produced by :meth:`Differ.compare` or :func:`ndiff`, extract
+ lines originating from file 1 or 2 (parameter *which*), stripping off line
+ prefixes.
+
+ Example::
+
+ >>> diff = ndiff('one\ntwo\nthree\n'.splitlines(1),
+ ... 'ore\ntree\nemu\n'.splitlines(1))
+ >>> diff = list(diff) # materialize the generated delta into a list
+ >>> print ''.join(restore(diff, 1)),
+ one
+ two
+ three
+ >>> print ''.join(restore(diff, 2)),
+ ore
+ tree
+ emu
+
+
+.. function:: unified_diff(a, b[, fromfile][, tofile][, fromfiledate][, tofiledate][, n][, lineterm])
+
+ Compare *a* and *b* (lists of strings); return a delta (a generator generating
+ the delta lines) in unified diff format.
+
+ Unified diffs are a compact way of showing just the lines that have changed plus
+ a few lines of context. The changes are shown in a inline style (instead of
+ separate before/after blocks). The number of context lines is set by *n* which
+ defaults to three.
+
+ By default, the diff control lines (those with ``---``, ``+++``, or ``@@``) are
+ created with a trailing newline. This is helpful so that inputs created from
+ :func:`file.readlines` result in diffs that are suitable for use with
+ :func:`file.writelines` since both the inputs and outputs have trailing
+ newlines.
+
+ For inputs that do not have trailing newlines, set the *lineterm* argument to
+ ``""`` so that the output will be uniformly newline free.
+
+ The context diff format normally has a header for filenames and modification
+ times. Any or all of these may be specified using strings for *fromfile*,
+ *tofile*, *fromfiledate*, and *tofiledate*. The modification times are normally
+ expressed in the format returned by :func:`time.ctime`. If not specified, the
+ strings default to blanks.
+
+ :file:`Tools/scripts/diff.py` is a command-line front-end for this function.
+
+ .. versionadded:: 2.3
+
+
+.. function:: IS_LINE_JUNK(line)
+
+ Return true for ignorable lines. The line *line* is ignorable if *line* is
+ blank or contains a single ``'#'``, otherwise it is not ignorable. Used as a
+ default for parameter *linejunk* in :func:`ndiff` before Python 2.3.
+
+
+.. function:: IS_CHARACTER_JUNK(ch)
+
+ Return true for ignorable characters. The character *ch* is ignorable if *ch*
+ is a space or tab, otherwise it is not ignorable. Used as a default for
+ parameter *charjunk* in :func:`ndiff`.
+
+
+.. seealso::
+
+ `Pattern Matching: The Gestalt Approach <http://www.ddj.com/184407970?pgno=5>`_
+ Discussion of a similar algorithm by John W. Ratcliff and D. E. Metzener. This
+ was published in `Dr. Dobb's Journal <http://www.ddj.com/>`_ in July, 1988.
+
+
+.. _sequence-matcher:
+
+SequenceMatcher Objects
+-----------------------
+
+The :class:`SequenceMatcher` class has this constructor:
+
+
+.. class:: SequenceMatcher([isjunk[, a[, b]]])
+
+ Optional argument *isjunk* must be ``None`` (the default) or a one-argument
+ function that takes a sequence element and returns true if and only if the
+ element is "junk" and should be ignored. Passing ``None`` for *isjunk* is
+ equivalent to passing ``lambda x: 0``; in other words, no elements are ignored.
+ For example, pass::
+
+ lambda x: x in " \t"
+
+ if you're comparing lines as sequences of characters, and don't want to synch up
+ on blanks or hard tabs.
+
+ The optional arguments *a* and *b* are sequences to be compared; both default to
+ empty strings. The elements of both sequences must be hashable.
+
+:class:`SequenceMatcher` objects have the following methods:
+
+
+.. method:: SequenceMatcher.set_seqs(a, b)
+
+ Set the two sequences to be compared.
+
+:class:`SequenceMatcher` computes and caches detailed information about the
+second sequence, so if you want to compare one sequence against many sequences,
+use :meth:`set_seq2` to set the commonly used sequence once and call
+:meth:`set_seq1` repeatedly, once for each of the other sequences.
+
+
+.. method:: SequenceMatcher.set_seq1(a)
+
+ Set the first sequence to be compared. The second sequence to be compared is
+ not changed.
+
+
+.. method:: SequenceMatcher.set_seq2(b)
+
+ Set the second sequence to be compared. The first sequence to be compared is
+ not changed.
+
+
+.. method:: SequenceMatcher.find_longest_match(alo, ahi, blo, bhi)
+
+ Find longest matching block in ``a[alo:ahi]`` and ``b[blo:bhi]``.
+
+ If *isjunk* was omitted or ``None``, :meth:`get_longest_match` returns ``(i, j,
+ k)`` such that ``a[i:i+k]`` is equal to ``b[j:j+k]``, where ``alo <= i <= i+k <=
+ ahi`` and ``blo <= j <= j+k <= bhi``. For all ``(i', j', k')`` meeting those
+ conditions, the additional conditions ``k >= k'``, ``i <= i'``, and if ``i ==
+ i'``, ``j <= j'`` are also met. In other words, of all maximal matching blocks,
+ return one that starts earliest in *a*, and of all those maximal matching blocks
+ that start earliest in *a*, return the one that starts earliest in *b*. ::
+
+ >>> s = SequenceMatcher(None, " abcd", "abcd abcd")
+ >>> s.find_longest_match(0, 5, 0, 9)
+ (0, 4, 5)
+
+ If *isjunk* was provided, first the longest matching block is determined as
+ above, but with the additional restriction that no junk element appears in the
+ block. Then that block is extended as far as possible by matching (only) junk
+ elements on both sides. So the resulting block never matches on junk except as
+ identical junk happens to be adjacent to an interesting match.
+
+ Here's the same example as before, but considering blanks to be junk. That
+ prevents ``' abcd'`` from matching the ``' abcd'`` at the tail end of the second
+ sequence directly. Instead only the ``'abcd'`` can match, and matches the
+ leftmost ``'abcd'`` in the second sequence::
+
+ >>> s = SequenceMatcher(lambda x: x==" ", " abcd", "abcd abcd")
+ >>> s.find_longest_match(0, 5, 0, 9)
+ (1, 0, 4)
+
+ If no blocks match, this returns ``(alo, blo, 0)``.
+
+
+.. method:: SequenceMatcher.get_matching_blocks()
+
+ Return list of triples describing matching subsequences. Each triple is of the
+ form ``(i, j, n)``, and means that ``a[i:i+n] == b[j:j+n]``. The triples are
+ monotonically increasing in *i* and *j*.
+
+ The last triple is a dummy, and has the value ``(len(a), len(b), 0)``. It is
+ the only triple with ``n == 0``. If ``(i, j, n)`` and ``(i', j', n')`` are
+ adjacent triples in the list, and the second is not the last triple in the list,
+ then ``i+n != i'`` or ``j+n != j'``; in other words, adjacent triples always
+ describe non-adjacent equal blocks.
+
+ .. % Explain why a dummy is used!
+
+ .. versionchanged:: 2.5
+ The guarantee that adjacent triples always describe non-adjacent blocks was
+ implemented.
+
+ ::
+
+ >>> s = SequenceMatcher(None, "abxcd", "abcd")
+ >>> s.get_matching_blocks()
+ [(0, 0, 2), (3, 2, 2), (5, 4, 0)]
+
+
+.. method:: SequenceMatcher.get_opcodes()
+
+ Return list of 5-tuples describing how to turn *a* into *b*. Each tuple is of
+ the form ``(tag, i1, i2, j1, j2)``. The first tuple has ``i1 == j1 == 0``, and
+ remaining tuples have *i1* equal to the *i2* from the preceding tuple, and,
+ likewise, *j1* equal to the previous *j2*.
+
+ The *tag* values are strings, with these meanings:
+
+ +---------------+---------------------------------------------+
+ | Value | Meaning |
+ +===============+=============================================+
+ | ``'replace'`` | ``a[i1:i2]`` should be replaced by |
+ | | ``b[j1:j2]``. |
+ +---------------+---------------------------------------------+
+ | ``'delete'`` | ``a[i1:i2]`` should be deleted. Note that |
+ | | ``j1 == j2`` in this case. |
+ +---------------+---------------------------------------------+
+ | ``'insert'`` | ``b[j1:j2]`` should be inserted at |
+ | | ``a[i1:i1]``. Note that ``i1 == i2`` in |
+ | | this case. |
+ +---------------+---------------------------------------------+
+ | ``'equal'`` | ``a[i1:i2] == b[j1:j2]`` (the sub-sequences |
+ | | are equal). |
+ +---------------+---------------------------------------------+
+
+ For example::
+
+ >>> a = "qabxcd"
+ >>> b = "abycdf"
+ >>> s = SequenceMatcher(None, a, b)
+ >>> for tag, i1, i2, j1, j2 in s.get_opcodes():
+ ... print ("%7s a[%d:%d] (%s) b[%d:%d] (%s)" %
+ ... (tag, i1, i2, a[i1:i2], j1, j2, b[j1:j2]))
+ delete a[0:1] (q) b[0:0] ()
+ equal a[1:3] (ab) b[0:2] (ab)
+ replace a[3:4] (x) b[2:3] (y)
+ equal a[4:6] (cd) b[3:5] (cd)
+ insert a[6:6] () b[5:6] (f)
+
+
+.. method:: SequenceMatcher.get_grouped_opcodes([n])
+
+ Return a generator of groups with up to *n* lines of context.
+
+ Starting with the groups returned by :meth:`get_opcodes`, this method splits out
+ smaller change clusters and eliminates intervening ranges which have no changes.
+
+ The groups are returned in the same format as :meth:`get_opcodes`.
+
+ .. versionadded:: 2.3
+
+
+.. method:: SequenceMatcher.ratio()
+
+ Return a measure of the sequences' similarity as a float in the range [0, 1].
+
+ Where T is the total number of elements in both sequences, and M is the number
+ of matches, this is 2.0\*M / T. Note that this is ``1.0`` if the sequences are
+ identical, and ``0.0`` if they have nothing in common.
+
+ This is expensive to compute if :meth:`get_matching_blocks` or
+ :meth:`get_opcodes` hasn't already been called, in which case you may want to
+ try :meth:`quick_ratio` or :meth:`real_quick_ratio` first to get an upper bound.
+
+
+.. method:: SequenceMatcher.quick_ratio()
+
+ Return an upper bound on :meth:`ratio` relatively quickly.
+
+ This isn't defined beyond that it is an upper bound on :meth:`ratio`, and is
+ faster to compute.
+
+
+.. method:: SequenceMatcher.real_quick_ratio()
+
+ Return an upper bound on :meth:`ratio` very quickly.
+
+ This isn't defined beyond that it is an upper bound on :meth:`ratio`, and is
+ faster to compute than either :meth:`ratio` or :meth:`quick_ratio`.
+
+The three methods that return the ratio of matching to total characters can give
+different results due to differing levels of approximation, although
+:meth:`quick_ratio` and :meth:`real_quick_ratio` are always at least as large as
+:meth:`ratio`::
+
+ >>> s = SequenceMatcher(None, "abcd", "bcde")
+ >>> s.ratio()
+ 0.75
+ >>> s.quick_ratio()
+ 0.75
+ >>> s.real_quick_ratio()
+ 1.0
+
+
+.. _sequencematcher-examples:
+
+SequenceMatcher Examples
+------------------------
+
+This example compares two strings, considering blanks to be "junk:" ::
+
+ >>> s = SequenceMatcher(lambda x: x == " ",
+ ... "private Thread currentThread;",
+ ... "private volatile Thread currentThread;")
+
+:meth:`ratio` returns a float in [0, 1], measuring the similarity of the
+sequences. As a rule of thumb, a :meth:`ratio` value over 0.6 means the
+sequences are close matches::
+
+ >>> print round(s.ratio(), 3)
+ 0.866
+
+If you're only interested in where the sequences match,
+:meth:`get_matching_blocks` is handy::
+
+ >>> for block in s.get_matching_blocks():
+ ... print "a[%d] and b[%d] match for %d elements" % block
+ a[0] and b[0] match for 8 elements
+ a[8] and b[17] match for 6 elements
+ a[14] and b[23] match for 15 elements
+ a[29] and b[38] match for 0 elements
+
+Note that the last tuple returned by :meth:`get_matching_blocks` is always a
+dummy, ``(len(a), len(b), 0)``, and this is the only case in which the last
+tuple element (number of elements matched) is ``0``.
+
+If you want to know how to change the first sequence into the second, use
+:meth:`get_opcodes`::
+
+ >>> for opcode in s.get_opcodes():
+ ... print "%6s a[%d:%d] b[%d:%d]" % opcode
+ equal a[0:8] b[0:8]
+ insert a[8:8] b[8:17]
+ equal a[8:14] b[17:23]
+ equal a[14:29] b[23:38]
+
+See also the function :func:`get_close_matches` in this module, which shows how
+simple code building on :class:`SequenceMatcher` can be used to do useful work.
+
+
+.. _differ-objects:
+
+Differ Objects
+--------------
+
+Note that :class:`Differ`\ -generated deltas make no claim to be **minimal**
+diffs. To the contrary, minimal diffs are often counter-intuitive, because they
+synch up anywhere possible, sometimes accidental matches 100 pages apart.
+Restricting synch points to contiguous matches preserves some notion of
+locality, at the occasional cost of producing a longer diff.
+
+The :class:`Differ` class has this constructor:
+
+
+.. class:: Differ([linejunk[, charjunk]])
+
+ Optional keyword parameters *linejunk* and *charjunk* are for filter functions
+ (or ``None``):
+
+ *linejunk*: A function that accepts a single string argument, and returns true
+ if the string is junk. The default is ``None``, meaning that no line is
+ considered junk.
+
+ *charjunk*: A function that accepts a single character argument (a string of
+ length 1), and returns true if the character is junk. The default is ``None``,
+ meaning that no character is considered junk.
+
+:class:`Differ` objects are used (deltas generated) via a single method:
+
+
+.. method:: Differ.compare(a, b)
+
+ Compare two sequences of lines, and generate the delta (a sequence of lines).
+
+ Each sequence must contain individual single-line strings ending with newlines.
+ Such sequences can be obtained from the :meth:`readlines` method of file-like
+ objects. The delta generated also consists of newline-terminated strings, ready
+ to be printed as-is via the :meth:`writelines` method of a file-like object.
+
+
+.. _differ-examples:
+
+Differ Example
+--------------
+
+This example compares two texts. First we set up the texts, sequences of
+individual single-line strings ending with newlines (such sequences can also be
+obtained from the :meth:`readlines` method of file-like objects)::
+
+ >>> text1 = ''' 1. Beautiful is better than ugly.
+ ... 2. Explicit is better than implicit.
+ ... 3. Simple is better than complex.
+ ... 4. Complex is better than complicated.
+ ... '''.splitlines(1)
+ >>> len(text1)
+ 4
+ >>> text1[0][-1]
+ '\n'
+ >>> text2 = ''' 1. Beautiful is better than ugly.
+ ... 3. Simple is better than complex.
+ ... 4. Complicated is better than complex.
+ ... 5. Flat is better than nested.
+ ... '''.splitlines(1)
+
+Next we instantiate a Differ object::
+
+ >>> d = Differ()
+
+Note that when instantiating a :class:`Differ` object we may pass functions to
+filter out line and character "junk." See the :meth:`Differ` constructor for
+details.
+
+Finally, we compare the two::
+
+ >>> result = list(d.compare(text1, text2))
+
+``result`` is a list of strings, so let's pretty-print it::
+
+ >>> from pprint import pprint
+ >>> pprint(result)
+ [' 1. Beautiful is better than ugly.\n',
+ '- 2. Explicit is better than implicit.\n',
+ '- 3. Simple is better than complex.\n',
+ '+ 3. Simple is better than complex.\n',
+ '? ++ \n',
+ '- 4. Complex is better than complicated.\n',
+ '? ^ ---- ^ \n',
+ '+ 4. Complicated is better than complex.\n',
+ '? ++++ ^ ^ \n',
+ '+ 5. Flat is better than nested.\n']
+
+As a single multi-line string it looks like this::
+
+ >>> import sys
+ >>> sys.stdout.writelines(result)
+ 1. Beautiful is better than ugly.
+ - 2. Explicit is better than implicit.
+ - 3. Simple is better than complex.
+ + 3. Simple is better than complex.
+ ? ++
+ - 4. Complex is better than complicated.
+ ? ^ ---- ^
+ + 4. Complicated is better than complex.
+ ? ++++ ^ ^
+ + 5. Flat is better than nested.
+
diff --git a/Doc/library/dircache.rst b/Doc/library/dircache.rst
new file mode 100644
index 0000000000..28aa667129
--- /dev/null
+++ b/Doc/library/dircache.rst
@@ -0,0 +1,56 @@
+
+:mod:`dircache` --- Cached directory listings
+=============================================
+
+.. module:: dircache
+ :synopsis: Return directory listing, with cache mechanism.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`dircache` module defines a function for reading directory listing
+using a cache, and cache invalidation using the *mtime* of the directory.
+Additionally, it defines a function to annotate directories by appending a
+slash.
+
+The :mod:`dircache` module defines the following functions:
+
+
+.. function:: reset()
+
+ Resets the directory cache.
+
+
+.. function:: listdir(path)
+
+ Return a directory listing of *path*, as gotten from :func:`os.listdir`. Note
+ that unless *path* changes, further call to :func:`listdir` will not re-read the
+ directory structure.
+
+ Note that the list returned should be regarded as read-only. (Perhaps a future
+ version should change it to return a tuple?)
+
+
+.. function:: opendir(path)
+
+ Same as :func:`listdir`. Defined for backwards compatibility.
+
+
+.. function:: annotate(head, list)
+
+ Assume *list* is a list of paths relative to *head*, and append, in place, a
+ ``'/'`` to each path which points to a directory.
+
+::
+
+ >>> import dircache
+ >>> a = dircache.listdir('/')
+ >>> a = a[:] # Copy the return value so we can change 'a'
+ >>> a
+ ['bin', 'boot', 'cdrom', 'dev', 'etc', 'floppy', 'home', 'initrd', 'lib', 'lost+
+ found', 'mnt', 'proc', 'root', 'sbin', 'tmp', 'usr', 'var', 'vmlinuz']
+ >>> dircache.annotate('/', a)
+ >>> a
+ ['bin/', 'boot/', 'cdrom/', 'dev/', 'etc/', 'floppy/', 'home/', 'initrd/', 'lib/
+ ', 'lost+found/', 'mnt/', 'proc/', 'root/', 'sbin/', 'tmp/', 'usr/', 'var/', 'vm
+ linuz']
+
diff --git a/Doc/library/dis.rst b/Doc/library/dis.rst
new file mode 100644
index 0000000000..5f2847305c
--- /dev/null
+++ b/Doc/library/dis.rst
@@ -0,0 +1,775 @@
+
+:mod:`dis` --- Disassembler for Python byte code
+================================================
+
+.. module:: dis
+ :synopsis: Disassembler for Python byte code.
+
+
+The :mod:`dis` module supports the analysis of Python byte code by disassembling
+it. Since there is no Python assembler, this module defines the Python assembly
+language. The Python byte code which this module takes as an input is defined
+in the file :file:`Include/opcode.h` and used by the compiler and the
+interpreter.
+
+Example: Given the function :func:`myfunc`::
+
+ def myfunc(alist):
+ return len(alist)
+
+the following command can be used to get the disassembly of :func:`myfunc`::
+
+ >>> dis.dis(myfunc)
+ 2 0 LOAD_GLOBAL 0 (len)
+ 3 LOAD_FAST 0 (alist)
+ 6 CALL_FUNCTION 1
+ 9 RETURN_VALUE
+
+(The "2" is a line number).
+
+The :mod:`dis` module defines the following functions and constants:
+
+
+.. function:: dis([bytesource])
+
+ Disassemble the *bytesource* object. *bytesource* can denote either a module, a
+ class, a method, a function, or a code object. For a module, it disassembles
+ all functions. For a class, it disassembles all methods. For a single code
+ sequence, it prints one line per byte code instruction. If no object is
+ provided, it disassembles the last traceback.
+
+
+.. function:: distb([tb])
+
+ Disassembles the top-of-stack function of a traceback, using the last traceback
+ if none was passed. The instruction causing the exception is indicated.
+
+
+.. function:: disassemble(code[, lasti])
+
+ Disassembles a code object, indicating the last instruction if *lasti* was
+ provided. The output is divided in the following columns:
+
+ #. the line number, for the first instruction of each line
+ #. the current instruction, indicated as ``-->``,
+ #. a labelled instruction, indicated with ``>>``,
+ #. the address of the instruction,
+ #. the operation code name,
+ #. operation parameters, and
+ #. interpretation of the parameters in parentheses.
+
+ The parameter interpretation recognizes local and global variable names,
+ constant values, branch targets, and compare operators.
+
+
+.. function:: disco(code[, lasti])
+
+ A synonym for disassemble. It is more convenient to type, and kept for
+ compatibility with earlier Python releases.
+
+
+.. data:: opname
+
+ Sequence of operation names, indexable using the byte code.
+
+
+.. data:: opmap
+
+ Dictionary mapping byte codes to operation names.
+
+
+.. data:: cmp_op
+
+ Sequence of all compare operation names.
+
+
+.. data:: hasconst
+
+ Sequence of byte codes that have a constant parameter.
+
+
+.. data:: hasfree
+
+ Sequence of byte codes that access a free variable.
+
+
+.. data:: hasname
+
+ Sequence of byte codes that access an attribute by name.
+
+
+.. data:: hasjrel
+
+ Sequence of byte codes that have a relative jump target.
+
+
+.. data:: hasjabs
+
+ Sequence of byte codes that have an absolute jump target.
+
+
+.. data:: haslocal
+
+ Sequence of byte codes that access a local variable.
+
+
+.. data:: hascompare
+
+ Sequence of byte codes of Boolean operations.
+
+
+.. _bytecodes:
+
+Python Byte Code Instructions
+-----------------------------
+
+The Python compiler currently generates the following byte code instructions.
+
+
+.. opcode:: STOP_CODE ()
+
+ Indicates end-of-code to the compiler, not used by the interpreter.
+
+
+.. opcode:: NOP ()
+
+ Do nothing code. Used as a placeholder by the bytecode optimizer.
+
+
+.. opcode:: POP_TOP ()
+
+ Removes the top-of-stack (TOS) item.
+
+
+.. opcode:: ROT_TWO ()
+
+ Swaps the two top-most stack items.
+
+
+.. opcode:: ROT_THREE ()
+
+ Lifts second and third stack item one position up, moves top down to position
+ three.
+
+
+.. opcode:: ROT_FOUR ()
+
+ Lifts second, third and forth stack item one position up, moves top down to
+ position four.
+
+
+.. opcode:: DUP_TOP ()
+
+ Duplicates the reference on top of the stack.
+
+Unary Operations take the top of the stack, apply the operation, and push the
+result back on the stack.
+
+
+.. opcode:: UNARY_POSITIVE ()
+
+ Implements ``TOS = +TOS``.
+
+
+.. opcode:: UNARY_NEGATIVE ()
+
+ Implements ``TOS = -TOS``.
+
+
+.. opcode:: UNARY_NOT ()
+
+ Implements ``TOS = not TOS``.
+
+
+.. opcode:: UNARY_INVERT ()
+
+ Implements ``TOS = ~TOS``.
+
+
+.. opcode:: GET_ITER ()
+
+ Implements ``TOS = iter(TOS)``.
+
+Binary operations remove the top of the stack (TOS) and the second top-most
+stack item (TOS1) from the stack. They perform the operation, and put the
+result back on the stack.
+
+
+.. opcode:: BINARY_POWER ()
+
+ Implements ``TOS = TOS1 ** TOS``.
+
+
+.. opcode:: BINARY_MULTIPLY ()
+
+ Implements ``TOS = TOS1 * TOS``.
+
+
+.. opcode:: BINARY_FLOOR_DIVIDE ()
+
+ Implements ``TOS = TOS1 // TOS``.
+
+
+.. opcode:: BINARY_TRUE_DIVIDE ()
+
+ Implements ``TOS = TOS1 / TOS`` when ``from __future__ import division`` is in
+ effect.
+
+
+.. opcode:: BINARY_MODULO ()
+
+ Implements ``TOS = TOS1 % TOS``.
+
+
+.. opcode:: BINARY_ADD ()
+
+ Implements ``TOS = TOS1 + TOS``.
+
+
+.. opcode:: BINARY_SUBTRACT ()
+
+ Implements ``TOS = TOS1 - TOS``.
+
+
+.. opcode:: BINARY_SUBSCR ()
+
+ Implements ``TOS = TOS1[TOS]``.
+
+
+.. opcode:: BINARY_LSHIFT ()
+
+ Implements ``TOS = TOS1 << TOS``.
+
+
+.. opcode:: BINARY_RSHIFT ()
+
+ Implements ``TOS = TOS1 >> TOS``.
+
+
+.. opcode:: BINARY_AND ()
+
+ Implements ``TOS = TOS1 & TOS``.
+
+
+.. opcode:: BINARY_XOR ()
+
+ Implements ``TOS = TOS1 ^ TOS``.
+
+
+.. opcode:: BINARY_OR ()
+
+ Implements ``TOS = TOS1 | TOS``.
+
+In-place operations are like binary operations, in that they remove TOS and
+TOS1, and push the result back on the stack, but the operation is done in-place
+when TOS1 supports it, and the resulting TOS may be (but does not have to be)
+the original TOS1.
+
+
+.. opcode:: INPLACE_POWER ()
+
+ Implements in-place ``TOS = TOS1 ** TOS``.
+
+
+.. opcode:: INPLACE_MULTIPLY ()
+
+ Implements in-place ``TOS = TOS1 * TOS``.
+
+
+.. opcode:: INPLACE_FLOOR_DIVIDE ()
+
+ Implements in-place ``TOS = TOS1 // TOS``.
+
+
+.. opcode:: INPLACE_TRUE_DIVIDE ()
+
+ Implements in-place ``TOS = TOS1 / TOS`` when ``from __future__ import
+ division`` is in effect.
+
+
+.. opcode:: INPLACE_MODULO ()
+
+ Implements in-place ``TOS = TOS1 % TOS``.
+
+
+.. opcode:: INPLACE_ADD ()
+
+ Implements in-place ``TOS = TOS1 + TOS``.
+
+
+.. opcode:: INPLACE_SUBTRACT ()
+
+ Implements in-place ``TOS = TOS1 - TOS``.
+
+
+.. opcode:: INPLACE_LSHIFT ()
+
+ Implements in-place ``TOS = TOS1 << TOS``.
+
+
+.. opcode:: INPLACE_RSHIFT ()
+
+ Implements in-place ``TOS = TOS1 >> TOS``.
+
+
+.. opcode:: INPLACE_AND ()
+
+ Implements in-place ``TOS = TOS1 & TOS``.
+
+
+.. opcode:: INPLACE_XOR ()
+
+ Implements in-place ``TOS = TOS1 ^ TOS``.
+
+
+.. opcode:: INPLACE_OR ()
+
+ Implements in-place ``TOS = TOS1 | TOS``.
+
+The slice opcodes take up to three parameters.
+
+
+.. opcode:: SLICE+0 ()
+
+ Implements ``TOS = TOS[:]``.
+
+
+.. opcode:: SLICE+1 ()
+
+ Implements ``TOS = TOS1[TOS:]``.
+
+
+.. opcode:: SLICE+2 ()
+
+ Implements ``TOS = TOS1[:TOS]``.
+
+
+.. opcode:: SLICE+3 ()
+
+ Implements ``TOS = TOS2[TOS1:TOS]``.
+
+Slice assignment needs even an additional parameter. As any statement, they put
+nothing on the stack.
+
+
+.. opcode:: STORE_SLICE+0 ()
+
+ Implements ``TOS[:] = TOS1``.
+
+
+.. opcode:: STORE_SLICE+1 ()
+
+ Implements ``TOS1[TOS:] = TOS2``.
+
+
+.. opcode:: STORE_SLICE+2 ()
+
+ Implements ``TOS1[:TOS] = TOS2``.
+
+
+.. opcode:: STORE_SLICE+3 ()
+
+ Implements ``TOS2[TOS1:TOS] = TOS3``.
+
+
+.. opcode:: DELETE_SLICE+0 ()
+
+ Implements ``del TOS[:]``.
+
+
+.. opcode:: DELETE_SLICE+1 ()
+
+ Implements ``del TOS1[TOS:]``.
+
+
+.. opcode:: DELETE_SLICE+2 ()
+
+ Implements ``del TOS1[:TOS]``.
+
+
+.. opcode:: DELETE_SLICE+3 ()
+
+ Implements ``del TOS2[TOS1:TOS]``.
+
+
+.. opcode:: STORE_SUBSCR ()
+
+ Implements ``TOS1[TOS] = TOS2``.
+
+
+.. opcode:: DELETE_SUBSCR ()
+
+ Implements ``del TOS1[TOS]``.
+
+Miscellaneous opcodes.
+
+
+.. opcode:: PRINT_EXPR ()
+
+ Implements the expression statement for the interactive mode. TOS is removed
+ from the stack and printed. In non-interactive mode, an expression statement is
+ terminated with ``POP_STACK``.
+
+
+.. opcode:: BREAK_LOOP ()
+
+ Terminates a loop due to a :keyword:`break` statement.
+
+
+.. opcode:: CONTINUE_LOOP (target)
+
+ Continues a loop due to a :keyword:`continue` statement. *target* is the
+ address to jump to (which should be a ``FOR_ITER`` instruction).
+
+
+.. opcode:: SET_ADD ()
+
+ Calls ``set.add(TOS1, TOS)``. Used to implement set comprehensions.
+
+
+.. opcode:: LIST_APPEND ()
+
+ Calls ``list.append(TOS1, TOS)``. Used to implement list comprehensions.
+
+
+.. opcode:: LOAD_LOCALS ()
+
+ Pushes a reference to the locals of the current scope on the stack. This is used
+ in the code for a class definition: After the class body is evaluated, the
+ locals are passed to the class definition.
+
+
+.. opcode:: RETURN_VALUE ()
+
+ Returns with TOS to the caller of the function.
+
+
+.. opcode:: YIELD_VALUE ()
+
+ Pops ``TOS`` and yields it from a generator.
+
+
+.. opcode:: IMPORT_STAR ()
+
+ Loads all symbols not starting with ``'_'`` directly from the module TOS to the
+ local namespace. The module is popped after loading all names. This opcode
+ implements ``from module import *``.
+
+
+.. opcode:: POP_BLOCK ()
+
+ Removes one block from the block stack. Per frame, there is a stack of blocks,
+ denoting nested loops, try statements, and such.
+
+
+.. opcode:: END_FINALLY ()
+
+ Terminates a :keyword:`finally` clause. The interpreter recalls whether the
+ exception has to be re-raised, or whether the function returns, and continues
+ with the outer-next block.
+
+
+.. opcode:: BUILD_CLASS ()
+
+ Creates a new class object. TOS is the methods dictionary, TOS1 the tuple of
+ the names of the base classes, and TOS2 the class name.
+
+All of the following opcodes expect arguments. An argument is two bytes, with
+the more significant byte last.
+
+
+.. opcode:: STORE_NAME (namei)
+
+ Implements ``name = TOS``. *namei* is the index of *name* in the attribute
+ :attr:`co_names` of the code object. The compiler tries to use ``STORE_LOCAL``
+ or ``STORE_GLOBAL`` if possible.
+
+
+.. opcode:: DELETE_NAME (namei)
+
+ Implements ``del name``, where *namei* is the index into :attr:`co_names`
+ attribute of the code object.
+
+
+.. opcode:: UNPACK_SEQUENCE (count)
+
+ Unpacks TOS into *count* individual values, which are put onto the stack
+ right-to-left.
+
+.. % \begin{opcodedesc}{UNPACK_LIST}{count}
+.. % This opcode is obsolete.
+.. % \end{opcodedesc}
+.. % \begin{opcodedesc}{UNPACK_ARG}{count}
+.. % This opcode is obsolete.
+.. % \end{opcodedesc}
+
+
+.. opcode:: DUP_TOPX (count)
+
+ Duplicate *count* items, keeping them in the same order. Due to implementation
+ limits, *count* should be between 1 and 5 inclusive.
+
+
+.. opcode:: STORE_ATTR (namei)
+
+ Implements ``TOS.name = TOS1``, where *namei* is the index of name in
+ :attr:`co_names`.
+
+
+.. opcode:: DELETE_ATTR (namei)
+
+ Implements ``del TOS.name``, using *namei* as index into :attr:`co_names`.
+
+
+.. opcode:: STORE_GLOBAL (namei)
+
+ Works as ``STORE_NAME``, but stores the name as a global.
+
+
+.. opcode:: DELETE_GLOBAL (namei)
+
+ Works as ``DELETE_NAME``, but deletes a global name.
+
+.. % \begin{opcodedesc}{UNPACK_VARARG}{argc}
+.. % This opcode is obsolete.
+.. % \end{opcodedesc}
+
+
+.. opcode:: LOAD_CONST (consti)
+
+ Pushes ``co_consts[consti]`` onto the stack.
+
+
+.. opcode:: LOAD_NAME (namei)
+
+ Pushes the value associated with ``co_names[namei]`` onto the stack.
+
+
+.. opcode:: BUILD_TUPLE (count)
+
+ Creates a tuple consuming *count* items from the stack, and pushes the resulting
+ tuple onto the stack.
+
+
+.. opcode:: BUILD_LIST (count)
+
+ Works as ``BUILD_TUPLE``, but creates a list.
+
+
+.. opcode:: BUILD_SET (count)
+
+ Works as ``BUILD_TUPLE``, but creates a set.
+
+
+.. opcode:: BUILD_MAP (zero)
+
+ Pushes a new empty dictionary object onto the stack. The argument is ignored
+ and set to zero by the compiler.
+
+
+.. opcode:: LOAD_ATTR (namei)
+
+ Replaces TOS with ``getattr(TOS, co_names[namei])``.
+
+
+.. opcode:: COMPARE_OP (opname)
+
+ Performs a Boolean operation. The operation name can be found in
+ ``cmp_op[opname]``.
+
+
+.. opcode:: IMPORT_NAME (namei)
+
+ Imports the module ``co_names[namei]``. The module object is pushed onto the
+ stack. The current namespace is not affected: for a proper import statement, a
+ subsequent ``STORE_FAST`` instruction modifies the namespace.
+
+
+.. opcode:: IMPORT_FROM (namei)
+
+ Loads the attribute ``co_names[namei]`` from the module found in TOS. The
+ resulting object is pushed onto the stack, to be subsequently stored by a
+ ``STORE_FAST`` instruction.
+
+
+.. opcode:: JUMP_FORWARD (delta)
+
+ Increments byte code counter by *delta*.
+
+
+.. opcode:: JUMP_IF_TRUE (delta)
+
+ If TOS is true, increment the byte code counter by *delta*. TOS is left on the
+ stack.
+
+
+.. opcode:: JUMP_IF_FALSE (delta)
+
+ If TOS is false, increment the byte code counter by *delta*. TOS is not
+ changed.
+
+
+.. opcode:: JUMP_ABSOLUTE (target)
+
+ Set byte code counter to *target*.
+
+
+.. opcode:: FOR_ITER (delta)
+
+ ``TOS`` is an iterator. Call its :meth:`__next__` method. If this yields a new
+ value, push it on the stack (leaving the iterator below it). If the iterator
+ indicates it is exhausted ``TOS`` is popped, and the byte code counter is
+ incremented by *delta*.
+
+.. % \begin{opcodedesc}{FOR_LOOP}{delta}
+.. % This opcode is obsolete.
+.. % \end{opcodedesc}
+.. % \begin{opcodedesc}{LOAD_LOCAL}{namei}
+.. % This opcode is obsolete.
+.. % \end{opcodedesc}
+
+
+.. opcode:: LOAD_GLOBAL (namei)
+
+ Loads the global named ``co_names[namei]`` onto the stack.
+
+.. % \begin{opcodedesc}{SET_FUNC_ARGS}{argc}
+.. % This opcode is obsolete.
+.. % \end{opcodedesc}
+
+
+.. opcode:: SETUP_LOOP (delta)
+
+ Pushes a block for a loop onto the block stack. The block spans from the
+ current instruction with a size of *delta* bytes.
+
+
+.. opcode:: SETUP_EXCEPT (delta)
+
+ Pushes a try block from a try-except clause onto the block stack. *delta* points
+ to the first except block.
+
+
+.. opcode:: SETUP_FINALLY (delta)
+
+ Pushes a try block from a try-except clause onto the block stack. *delta* points
+ to the finally block.
+
+
+.. opcode:: LOAD_FAST (var_num)
+
+ Pushes a reference to the local ``co_varnames[var_num]`` onto the stack.
+
+
+.. opcode:: STORE_FAST (var_num)
+
+ Stores TOS into the local ``co_varnames[var_num]``.
+
+
+.. opcode:: DELETE_FAST (var_num)
+
+ Deletes local ``co_varnames[var_num]``.
+
+
+.. opcode:: LOAD_CLOSURE (i)
+
+ Pushes a reference to the cell contained in slot *i* of the cell and free
+ variable storage. The name of the variable is ``co_cellvars[i]`` if *i* is
+ less than the length of *co_cellvars*. Otherwise it is ``co_freevars[i -
+ len(co_cellvars)]``.
+
+
+.. opcode:: LOAD_DEREF (i)
+
+ Loads the cell contained in slot *i* of the cell and free variable storage.
+ Pushes a reference to the object the cell contains on the stack.
+
+
+.. opcode:: STORE_DEREF (i)
+
+ Stores TOS into the cell contained in slot *i* of the cell and free variable
+ storage.
+
+
+.. opcode:: SET_LINENO (lineno)
+
+ This opcode is obsolete.
+
+
+.. opcode:: RAISE_VARARGS (argc)
+
+ Raises an exception. *argc* indicates the number of parameters to the raise
+ statement, ranging from 0 to 3. The handler will find the traceback as TOS2,
+ the parameter as TOS1, and the exception as TOS.
+
+
+.. opcode:: CALL_FUNCTION (argc)
+
+ Calls a function. The low byte of *argc* indicates the number of positional
+ parameters, the high byte the number of keyword parameters. On the stack, the
+ opcode finds the keyword parameters first. For each keyword argument, the value
+ is on top of the key. Below the keyword parameters, the positional parameters
+ are on the stack, with the right-most parameter on top. Below the parameters,
+ the function object to call is on the stack.
+
+
+.. opcode:: MAKE_FUNCTION (argc)
+
+ Pushes a new function object on the stack. TOS is the code associated with the
+ function. The function object is defined to have *argc* default parameters,
+ which are found below TOS.
+
+
+.. opcode:: MAKE_CLOSURE (argc)
+
+ Creates a new function object, sets its *__closure__* slot, and pushes it on the
+ stack. TOS is the code associated with the function. If the code object has N
+ free variables, the next N items on the stack are the cells for these variables.
+ The function also has *argc* default parameters, where are found before the
+ cells.
+
+
+.. opcode:: BUILD_SLICE (argc)
+
+ .. index:: builtin: slice
+
+ Pushes a slice object on the stack. *argc* must be 2 or 3. If it is 2,
+ ``slice(TOS1, TOS)`` is pushed; if it is 3, ``slice(TOS2, TOS1, TOS)`` is
+ pushed. See the ``slice()`` built-in function for more information.
+
+
+.. opcode:: EXTENDED_ARG (ext)
+
+ Prefixes any opcode which has an argument too big to fit into the default two
+ bytes. *ext* holds two additional bytes which, taken together with the
+ subsequent opcode's argument, comprise a four-byte argument, *ext* being the two
+ most-significant bytes.
+
+
+.. opcode:: CALL_FUNCTION_VAR (argc)
+
+ Calls a function. *argc* is interpreted as in ``CALL_FUNCTION``. The top element
+ on the stack contains the variable argument list, followed by keyword and
+ positional arguments.
+
+
+.. opcode:: CALL_FUNCTION_KW (argc)
+
+ Calls a function. *argc* is interpreted as in ``CALL_FUNCTION``. The top element
+ on the stack contains the keyword arguments dictionary, followed by explicit
+ keyword and positional arguments.
+
+
+.. opcode:: CALL_FUNCTION_VAR_KW (argc)
+
+ Calls a function. *argc* is interpreted as in ``CALL_FUNCTION``. The top
+ element on the stack contains the keyword arguments dictionary, followed by the
+ variable-arguments tuple, followed by explicit keyword and positional arguments.
+
+
+.. opcode:: HAVE_ARGUMENT ()
+
+ This is not really an opcode. It identifies the dividing line between opcodes
+ which don't take arguments ``< HAVE_ARGUMENT`` and those which do ``>=
+ HAVE_ARGUMENT``.
+
diff --git a/Doc/library/distutils.rst b/Doc/library/distutils.rst
new file mode 100644
index 0000000000..534faab407
--- /dev/null
+++ b/Doc/library/distutils.rst
@@ -0,0 +1,30 @@
+
+:mod:`distutils` --- Building and installing Python modules
+===========================================================
+
+.. module:: distutils
+ :synopsis: Support for building and installing Python modules into an existing Python
+ installation.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`distutils` package provides support for building and installing
+additional modules into a Python installation. The new modules may be either
+100%-pure Python, or may be extension modules written in C, or may be
+collections of Python packages which include modules coded in both Python and C.
+
+This package is discussed in two separate chapters:
+
+
+.. seealso::
+
+ :ref:`distutils-index`
+ The manual for developers and packagers of Python modules. This describes how
+ to prepare :mod:`distutils`\ -based packages so that they may be easily
+ installed into an existing Python installation.
+
+ :ref:`install-index`
+ An "administrators" manual which includes information on installing modules into
+ an existing Python installation. You do not need to be a Python programmer to
+ read this manual.
+
diff --git a/Doc/library/dl.rst b/Doc/library/dl.rst
new file mode 100644
index 0000000000..ff42619119
--- /dev/null
+++ b/Doc/library/dl.rst
@@ -0,0 +1,111 @@
+
+:mod:`dl` --- Call C functions in shared objects
+================================================
+
+.. module:: dl
+ :platform: Unix
+ :synopsis: Call C functions in shared objects.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+.. % ?????????? Anyone????????????
+
+The :mod:`dl` module defines an interface to the :cfunc:`dlopen` function, which
+is the most common interface on Unix platforms for handling dynamically linked
+libraries. It allows the program to call arbitrary functions in such a library.
+
+.. warning::
+
+ The :mod:`dl` module bypasses the Python type system and error handling. If
+ used incorrectly it may cause segmentation faults, crashes or other incorrect
+ behaviour.
+
+.. note::
+
+ This module will not work unless ``sizeof(int) == sizeof(long) == sizeof(char
+ *)`` If this is not the case, :exc:`SystemError` will be raised on import.
+
+The :mod:`dl` module defines the following function:
+
+
+.. function:: open(name[, mode=RTLD_LAZY])
+
+ Open a shared object file, and return a handle. Mode signifies late binding
+ (:const:`RTLD_LAZY`) or immediate binding (:const:`RTLD_NOW`). Default is
+ :const:`RTLD_LAZY`. Note that some systems do not support :const:`RTLD_NOW`.
+
+ Return value is a :class:`dlobject`.
+
+The :mod:`dl` module defines the following constants:
+
+
+.. data:: RTLD_LAZY
+
+ Useful as an argument to :func:`open`.
+
+
+.. data:: RTLD_NOW
+
+ Useful as an argument to :func:`open`. Note that on systems which do not
+ support immediate binding, this constant will not appear in the module. For
+ maximum portability, use :func:`hasattr` to determine if the system supports
+ immediate binding.
+
+The :mod:`dl` module defines the following exception:
+
+
+.. exception:: error
+
+ Exception raised when an error has occurred inside the dynamic loading and
+ linking routines.
+
+Example::
+
+ >>> import dl, time
+ >>> a=dl.open('/lib/libc.so.6')
+ >>> a.call('time'), time.time()
+ (929723914, 929723914.498)
+
+This example was tried on a Debian GNU/Linux system, and is a good example of
+the fact that using this module is usually a bad alternative.
+
+
+.. _dl-objects:
+
+Dl Objects
+----------
+
+Dl objects, as returned by :func:`open` above, have the following methods:
+
+
+.. method:: dl.close()
+
+ Free all resources, except the memory.
+
+
+.. method:: dl.sym(name)
+
+ Return the pointer for the function named *name*, as a number, if it exists in
+ the referenced shared object, otherwise ``None``. This is useful in code like::
+
+ >>> if a.sym('time'):
+ ... a.call('time')
+ ... else:
+ ... time.time()
+
+ (Note that this function will return a non-zero number, as zero is the *NULL*
+ pointer)
+
+
+.. method:: dl.call(name[, arg1[, arg2...]])
+
+ Call the function named *name* in the referenced shared object. The arguments
+ must be either Python integers, which will be passed as is, Python strings, to
+ which a pointer will be passed, or ``None``, which will be passed as *NULL*.
+ Note that strings should only be passed to functions as :ctype:`const char\*`,
+ as Python will not like its string mutated.
+
+ There must be at most 10 arguments, and arguments not given will be treated as
+ ``None``. The function's return value must be a C :ctype:`long`, which is a
+ Python integer.
+
diff --git a/Doc/library/doctest.rst b/Doc/library/doctest.rst
new file mode 100644
index 0000000000..23f96e4ff2
--- /dev/null
+++ b/Doc/library/doctest.rst
@@ -0,0 +1,1869 @@
+:mod:`doctest` --- Test interactive Python examples
+===================================================
+
+.. module:: doctest
+ :synopsis: Test pieces of code within docstrings.
+.. moduleauthor:: Tim Peters <tim@python.org>
+.. sectionauthor:: Tim Peters <tim@python.org>
+.. sectionauthor:: Moshe Zadka <moshez@debian.org>
+.. sectionauthor:: Edward Loper <edloper@users.sourceforge.net>
+
+
+The :mod:`doctest` module searches for pieces of text that look like interactive
+Python sessions, and then executes those sessions to verify that they work
+exactly as shown. There are several common ways to use doctest:
+
+* To check that a module's docstrings are up-to-date by verifying that all
+ interactive examples still work as documented.
+
+* To perform regression testing by verifying that interactive examples from a
+ test file or a test object work as expected.
+
+* To write tutorial documentation for a package, liberally illustrated with
+ input-output examples. Depending on whether the examples or the expository text
+ are emphasized, this has the flavor of "literate testing" or "executable
+ documentation".
+
+Here's a complete but small example module::
+
+ """
+ This is the "example" module.
+
+ The example module supplies one function, factorial(). For example,
+
+ >>> factorial(5)
+ 120
+ """
+
+ def factorial(n):
+ """Return the factorial of n, an exact integer >= 0.
+
+ If the result is small enough to fit in an int, return an int.
+ Else return a long.
+
+ >>> [factorial(n) for n in range(6)]
+ [1, 1, 2, 6, 24, 120]
+ >>> [factorial(long(n)) for n in range(6)]
+ [1, 1, 2, 6, 24, 120]
+ >>> factorial(30)
+ 265252859812191058636308480000000L
+ >>> factorial(30L)
+ 265252859812191058636308480000000L
+ >>> factorial(-1)
+ Traceback (most recent call last):
+ ...
+ ValueError: n must be >= 0
+
+ Factorials of floats are OK, but the float must be an exact integer:
+ >>> factorial(30.1)
+ Traceback (most recent call last):
+ ...
+ ValueError: n must be exact integer
+ >>> factorial(30.0)
+ 265252859812191058636308480000000L
+
+ It must also not be ridiculously large:
+ >>> factorial(1e100)
+ Traceback (most recent call last):
+ ...
+ OverflowError: n too large
+ """
+
+
+.. % allow LaTeX to break here.
+
+::
+
+ import math
+ if not n >= 0:
+ raise ValueError("n must be >= 0")
+ if math.floor(n) != n:
+ raise ValueError("n must be exact integer")
+ if n+1 == n: # catch a value like 1e300
+ raise OverflowError("n too large")
+ result = 1
+ factor = 2
+ while factor <= n:
+ result *= factor
+ factor += 1
+ return result
+
+ def _test():
+ import doctest
+ doctest.testmod()
+
+ if __name__ == "__main__":
+ _test()
+
+If you run :file:`example.py` directly from the command line, :mod:`doctest`
+works its magic::
+
+ $ python example.py
+ $
+
+There's no output! That's normal, and it means all the examples worked. Pass
+:option:`-v` to the script, and :mod:`doctest` prints a detailed log of what
+it's trying, and prints a summary at the end::
+
+ $ python example.py -v
+ Trying:
+ factorial(5)
+ Expecting:
+ 120
+ ok
+ Trying:
+ [factorial(n) for n in range(6)]
+ Expecting:
+ [1, 1, 2, 6, 24, 120]
+ ok
+ Trying:
+ [factorial(long(n)) for n in range(6)]
+ Expecting:
+ [1, 1, 2, 6, 24, 120]
+ ok
+
+And so on, eventually ending with::
+
+ Trying:
+ factorial(1e100)
+ Expecting:
+ Traceback (most recent call last):
+ ...
+ OverflowError: n too large
+ ok
+ 1 items had no tests:
+ __main__._test
+ 2 items passed all tests:
+ 1 tests in __main__
+ 8 tests in __main__.factorial
+ 9 tests in 3 items.
+ 9 passed and 0 failed.
+ Test passed.
+ $
+
+That's all you need to know to start making productive use of :mod:`doctest`!
+Jump in. The following sections provide full details. Note that there are many
+examples of doctests in the standard Python test suite and libraries.
+Especially useful examples can be found in the standard test file
+:file:`Lib/test/test_doctest.py`.
+
+
+.. _doctest-simple-testmod:
+
+Simple Usage: Checking Examples in Docstrings
+---------------------------------------------
+
+The simplest way to start using doctest (but not necessarily the way you'll
+continue to do it) is to end each module :mod:`M` with::
+
+ def _test():
+ import doctest
+ doctest.testmod()
+
+ if __name__ == "__main__":
+ _test()
+
+:mod:`doctest` then examines docstrings in module :mod:`M`.
+
+Running the module as a script causes the examples in the docstrings to get
+executed and verified::
+
+ python M.py
+
+This won't display anything unless an example fails, in which case the failing
+example(s) and the cause(s) of the failure(s) are printed to stdout, and the
+final line of output is ``***Test Failed*** N failures.``, where *N* is the
+number of examples that failed.
+
+Run it with the :option:`-v` switch instead::
+
+ python M.py -v
+
+and a detailed report of all examples tried is printed to standard output, along
+with assorted summaries at the end.
+
+You can force verbose mode by passing ``verbose=True`` to :func:`testmod`, or
+prohibit it by passing ``verbose=False``. In either of those cases,
+``sys.argv`` is not examined by :func:`testmod` (so passing :option:`-v` or not
+has no effect).
+
+Since Python 2.6, there is also a command line shortcut for running
+:func:`testmod`. You can instruct the Python interpreter to run the doctest
+module directly from the standard library and pass the module name(s) on the
+command line::
+
+ python -m doctest -v example.py
+
+This will import :file:`example.py` as a standalone module and run
+:func:`testmod` on it. Note that this may not work correctly if the file is
+part of a package and imports other submodules from that package.
+
+For more information on :func:`testmod`, see section :ref:`doctest-basic-api`.
+
+
+.. _doctest-simple-testfile:
+
+Simple Usage: Checking Examples in a Text File
+----------------------------------------------
+
+Another simple application of doctest is testing interactive examples in a text
+file. This can be done with the :func:`testfile` function::
+
+ import doctest
+ doctest.testfile("example.txt")
+
+That short script executes and verifies any interactive Python examples
+contained in the file :file:`example.txt`. The file content is treated as if it
+were a single giant docstring; the file doesn't need to contain a Python
+program! For example, perhaps :file:`example.txt` contains this::
+
+ The ``example`` module
+ ======================
+
+ Using ``factorial``
+ -------------------
+
+ This is an example text file in reStructuredText format. First import
+ ``factorial`` from the ``example`` module:
+
+ >>> from example import factorial
+
+ Now use it:
+
+ >>> factorial(6)
+ 120
+
+Running ``doctest.testfile("example.txt")`` then finds the error in this
+documentation::
+
+ File "./example.txt", line 14, in example.txt
+ Failed example:
+ factorial(6)
+ Expected:
+ 120
+ Got:
+ 720
+
+As with :func:`testmod`, :func:`testfile` won't display anything unless an
+example fails. If an example does fail, then the failing example(s) and the
+cause(s) of the failure(s) are printed to stdout, using the same format as
+:func:`testmod`.
+
+By default, :func:`testfile` looks for files in the calling module's directory.
+See section :ref:`doctest-basic-api` for a description of the optional arguments
+that can be used to tell it to look for files in other locations.
+
+Like :func:`testmod`, :func:`testfile`'s verbosity can be set with the
+:option:`-v` command-line switch or with the optional keyword argument
+*verbose*.
+
+Since Python 2.6, there is also a command line shortcut for running
+:func:`testfile`. You can instruct the Python interpreter to run the doctest
+module directly from the standard library and pass the file name(s) on the
+command line::
+
+ python -m doctest -v example.txt
+
+Because the file name does not end with :file:`.py`, :mod:`doctest` infers that
+it must be run with :func:`testfile`, not :func:`testmod`.
+
+For more information on :func:`testfile`, see section :ref:`doctest-basic-api`.
+
+
+.. _doctest-how-it-works:
+
+How It Works
+------------
+
+This section examines in detail how doctest works: which docstrings it looks at,
+how it finds interactive examples, what execution context it uses, how it
+handles exceptions, and how option flags can be used to control its behavior.
+This is the information that you need to know to write doctest examples; for
+information about actually running doctest on these examples, see the following
+sections.
+
+
+.. _doctest-which-docstrings:
+
+Which Docstrings Are Examined?
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The module docstring, and all function, class and method docstrings are
+searched. Objects imported into the module are not searched.
+
+In addition, if ``M.__test__`` exists and "is true", it must be a dict, and each
+entry maps a (string) name to a function object, class object, or string.
+Function and class object docstrings found from ``M.__test__`` are searched, and
+strings are treated as if they were docstrings. In output, a key ``K`` in
+``M.__test__`` appears with name ::
+
+ <name of M>.__test__.K
+
+Any classes found are recursively searched similarly, to test docstrings in
+their contained methods and nested classes.
+
+.. versionchanged:: 2.4
+ A "private name" concept is deprecated and no longer documented.
+
+
+.. _doctest-finding-examples:
+
+How are Docstring Examples Recognized?
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In most cases a copy-and-paste of an interactive console session works fine, but
+doctest isn't trying to do an exact emulation of any specific Python shell. All
+hard tab characters are expanded to spaces, using 8-column tab stops. If you
+don't believe tabs should mean that, too bad: don't use hard tabs, or write
+your own :class:`DocTestParser` class.
+
+.. versionchanged:: 2.4
+ Expanding tabs to spaces is new; previous versions tried to preserve hard tabs,
+ with confusing results.
+
+::
+
+ >>> # comments are ignored
+ >>> x = 12
+ >>> x
+ 12
+ >>> if x == 13:
+ ... print "yes"
+ ... else:
+ ... print "no"
+ ... print "NO"
+ ... print "NO!!!"
+ ...
+ no
+ NO
+ NO!!!
+ >>>
+
+Any expected output must immediately follow the final ``'>>> '`` or ``'... '``
+line containing the code, and the expected output (if any) extends to the next
+``'>>> '`` or all-whitespace line.
+
+The fine print:
+
+* Expected output cannot contain an all-whitespace line, since such a line is
+ taken to signal the end of expected output. If expected output does contain a
+ blank line, put ``<BLANKLINE>`` in your doctest example each place a blank line
+ is expected.
+
+ .. versionchanged:: 2.4
+ ``<BLANKLINE>`` was added; there was no way to use expected output containing
+ empty lines in previous versions.
+
+* Output to stdout is captured, but not output to stderr (exception tracebacks
+ are captured via a different means).
+
+* If you continue a line via backslashing in an interactive session, or for any
+ other reason use a backslash, you should use a raw docstring, which will
+ preserve your backslashes exactly as you type them::
+
+ >>> def f(x):
+ ... r'''Backslashes in a raw docstring: m\n'''
+ >>> print f.__doc__
+ Backslashes in a raw docstring: m\n
+
+ Otherwise, the backslash will be interpreted as part of the string. For example,
+ the "\\" above would be interpreted as a newline character. Alternatively, you
+ can double each backslash in the doctest version (and not use a raw string)::
+
+ >>> def f(x):
+ ... '''Backslashes in a raw docstring: m\\n'''
+ >>> print f.__doc__
+ Backslashes in a raw docstring: m\n
+
+* The starting column doesn't matter::
+
+ >>> assert "Easy!"
+ >>> import math
+ >>> math.floor(1.9)
+ 1.0
+
+ and as many leading whitespace characters are stripped from the expected output
+ as appeared in the initial ``'>>> '`` line that started the example.
+
+
+.. _doctest-execution-context:
+
+What's the Execution Context?
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+By default, each time :mod:`doctest` finds a docstring to test, it uses a
+*shallow copy* of :mod:`M`'s globals, so that running tests doesn't change the
+module's real globals, and so that one test in :mod:`M` can't leave behind
+crumbs that accidentally allow another test to work. This means examples can
+freely use any names defined at top-level in :mod:`M`, and names defined earlier
+in the docstring being run. Examples cannot see names defined in other
+docstrings.
+
+You can force use of your own dict as the execution context by passing
+``globs=your_dict`` to :func:`testmod` or :func:`testfile` instead.
+
+
+.. _doctest-exceptions:
+
+What About Exceptions?
+^^^^^^^^^^^^^^^^^^^^^^
+
+No problem, provided that the traceback is the only output produced by the
+example: just paste in the traceback. [#]_ Since tracebacks contain details
+that are likely to change rapidly (for example, exact file paths and line
+numbers), this is one case where doctest works hard to be flexible in what it
+accepts.
+
+Simple example::
+
+ >>> [1, 2, 3].remove(42)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: list.remove(x): x not in list
+
+That doctest succeeds if :exc:`ValueError` is raised, with the ``list.remove(x):
+x not in list`` detail as shown.
+
+The expected output for an exception must start with a traceback header, which
+may be either of the following two lines, indented the same as the first line of
+the example::
+
+ Traceback (most recent call last):
+ Traceback (innermost last):
+
+The traceback header is followed by an optional traceback stack, whose contents
+are ignored by doctest. The traceback stack is typically omitted, or copied
+verbatim from an interactive session.
+
+The traceback stack is followed by the most interesting part: the line(s)
+containing the exception type and detail. This is usually the last line of a
+traceback, but can extend across multiple lines if the exception has a
+multi-line detail::
+
+ >>> raise ValueError('multi\n line\ndetail')
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: multi
+ line
+ detail
+
+The last three lines (starting with :exc:`ValueError`) are compared against the
+exception's type and detail, and the rest are ignored.
+
+Best practice is to omit the traceback stack, unless it adds significant
+documentation value to the example. So the last example is probably better as::
+
+ >>> raise ValueError('multi\n line\ndetail')
+ Traceback (most recent call last):
+ ...
+ ValueError: multi
+ line
+ detail
+
+Note that tracebacks are treated very specially. In particular, in the
+rewritten example, the use of ``...`` is independent of doctest's
+:const:`ELLIPSIS` option. The ellipsis in that example could be left out, or
+could just as well be three (or three hundred) commas or digits, or an indented
+transcript of a Monty Python skit.
+
+Some details you should read once, but won't need to remember:
+
+* Doctest can't guess whether your expected output came from an exception
+ traceback or from ordinary printing. So, e.g., an example that expects
+ ``ValueError: 42 is prime`` will pass whether :exc:`ValueError` is actually
+ raised or if the example merely prints that traceback text. In practice,
+ ordinary output rarely begins with a traceback header line, so this doesn't
+ create real problems.
+
+* Each line of the traceback stack (if present) must be indented further than
+ the first line of the example, *or* start with a non-alphanumeric character.
+ The first line following the traceback header indented the same and starting
+ with an alphanumeric is taken to be the start of the exception detail. Of
+ course this does the right thing for genuine tracebacks.
+
+* When the :const:`IGNORE_EXCEPTION_DETAIL` doctest option is is specified,
+ everything following the leftmost colon is ignored.
+
+* The interactive shell omits the traceback header line for some
+ :exc:`SyntaxError`\ s. But doctest uses the traceback header line to
+ distinguish exceptions from non-exceptions. So in the rare case where you need
+ to test a :exc:`SyntaxError` that omits the traceback header, you will need to
+ manually add the traceback header line to your test example.
+
+* For some :exc:`SyntaxError`\ s, Python displays the character position of the
+ syntax error, using a ``^`` marker::
+
+ >>> 1 1
+ File "<stdin>", line 1
+ 1 1
+ ^
+ SyntaxError: invalid syntax
+
+ Since the lines showing the position of the error come before the exception type
+ and detail, they are not checked by doctest. For example, the following test
+ would pass, even though it puts the ``^`` marker in the wrong location::
+
+ >>> 1 1
+ Traceback (most recent call last):
+ File "<stdin>", line 1
+ 1 1
+ ^
+ SyntaxError: invalid syntax
+
+.. versionchanged:: 2.4
+ The ability to handle a multi-line exception detail, and the
+ :const:`IGNORE_EXCEPTION_DETAIL` doctest option, were added.
+
+
+.. _doctest-options:
+
+Option Flags and Directives
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+A number of option flags control various aspects of doctest's behavior.
+Symbolic names for the flags are supplied as module constants, which can be
+or'ed together and passed to various functions. The names can also be used in
+doctest directives (see below).
+
+The first group of options define test semantics, controlling aspects of how
+doctest decides whether actual output matches an example's expected output:
+
+
+.. data:: DONT_ACCEPT_TRUE_FOR_1
+
+ By default, if an expected output block contains just ``1``, an actual output
+ block containing just ``1`` or just ``True`` is considered to be a match, and
+ similarly for ``0`` versus ``False``. When :const:`DONT_ACCEPT_TRUE_FOR_1` is
+ specified, neither substitution is allowed. The default behavior caters to that
+ Python changed the return type of many functions from integer to boolean;
+ doctests expecting "little integer" output still work in these cases. This
+ option will probably go away, but not for several years.
+
+
+.. data:: DONT_ACCEPT_BLANKLINE
+
+ By default, if an expected output block contains a line containing only the
+ string ``<BLANKLINE>``, then that line will match a blank line in the actual
+ output. Because a genuinely blank line delimits the expected output, this is
+ the only way to communicate that a blank line is expected. When
+ :const:`DONT_ACCEPT_BLANKLINE` is specified, this substitution is not allowed.
+
+
+.. data:: NORMALIZE_WHITESPACE
+
+ When specified, all sequences of whitespace (blanks and newlines) are treated as
+ equal. Any sequence of whitespace within the expected output will match any
+ sequence of whitespace within the actual output. By default, whitespace must
+ match exactly. :const:`NORMALIZE_WHITESPACE` is especially useful when a line of
+ expected output is very long, and you want to wrap it across multiple lines in
+ your source.
+
+
+.. data:: ELLIPSIS
+
+ When specified, an ellipsis marker (``...``) in the expected output can match
+ any substring in the actual output. This includes substrings that span line
+ boundaries, and empty substrings, so it's best to keep usage of this simple.
+ Complicated uses can lead to the same kinds of "oops, it matched too much!"
+ surprises that ``.*`` is prone to in regular expressions.
+
+
+.. data:: IGNORE_EXCEPTION_DETAIL
+
+ When specified, an example that expects an exception passes if an exception of
+ the expected type is raised, even if the exception detail does not match. For
+ example, an example expecting ``ValueError: 42`` will pass if the actual
+ exception raised is ``ValueError: 3*14``, but will fail, e.g., if
+ :exc:`TypeError` is raised.
+
+ Note that a similar effect can be obtained using :const:`ELLIPSIS`, and
+ :const:`IGNORE_EXCEPTION_DETAIL` may go away when Python releases prior to 2.4
+ become uninteresting. Until then, :const:`IGNORE_EXCEPTION_DETAIL` is the only
+ clear way to write a doctest that doesn't care about the exception detail yet
+ continues to pass under Python releases prior to 2.4 (doctest directives appear
+ to be comments to them). For example, ::
+
+ >>> (1, 2)[3] = 'moo' #doctest: +IGNORE_EXCEPTION_DETAIL
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: object doesn't support item assignment
+
+ passes under Python 2.4 and Python 2.3. The detail changed in 2.4, to say "does
+ not" instead of "doesn't".
+
+
+.. data:: SKIP
+
+ When specified, do not run the example at all. This can be useful in contexts
+ where doctest examples serve as both documentation and test cases, and an
+ example should be included for documentation purposes, but should not be
+ checked. E.g., the example's output might be random; or the example might
+ depend on resources which would be unavailable to the test driver.
+
+ The SKIP flag can also be used for temporarily "commenting out" examples.
+
+
+.. data:: COMPARISON_FLAGS
+
+ A bitmask or'ing together all the comparison flags above.
+
+The second group of options controls how test failures are reported:
+
+
+.. data:: REPORT_UDIFF
+
+ When specified, failures that involve multi-line expected and actual outputs are
+ displayed using a unified diff.
+
+
+.. data:: REPORT_CDIFF
+
+ When specified, failures that involve multi-line expected and actual outputs
+ will be displayed using a context diff.
+
+
+.. data:: REPORT_NDIFF
+
+ When specified, differences are computed by ``difflib.Differ``, using the same
+ algorithm as the popular :file:`ndiff.py` utility. This is the only method that
+ marks differences within lines as well as across lines. For example, if a line
+ of expected output contains digit ``1`` where actual output contains letter
+ ``l``, a line is inserted with a caret marking the mismatching column positions.
+
+
+.. data:: REPORT_ONLY_FIRST_FAILURE
+
+ When specified, display the first failing example in each doctest, but suppress
+ output for all remaining examples. This will prevent doctest from reporting
+ correct examples that break because of earlier failures; but it might also hide
+ incorrect examples that fail independently of the first failure. When
+ :const:`REPORT_ONLY_FIRST_FAILURE` is specified, the remaining examples are
+ still run, and still count towards the total number of failures reported; only
+ the output is suppressed.
+
+
+.. data:: REPORTING_FLAGS
+
+ A bitmask or'ing together all the reporting flags above.
+
+"Doctest directives" may be used to modify the option flags for individual
+examples. Doctest directives are expressed as a special Python comment
+following an example's source code:
+
+.. productionlist:: doctest
+ directive: "#" "doctest:" `directive_options`
+ directive_options: `directive_option` ("," `directive_option`)\*
+ directive_option: `on_or_off` `directive_option_name`
+ on_or_off: "+" \| "-"
+ directive_option_name: "DONT_ACCEPT_BLANKLINE" \| "NORMALIZE_WHITESPACE" \| ...
+
+Whitespace is not allowed between the ``+`` or ``-`` and the directive option
+name. The directive option name can be any of the option flag names explained
+above.
+
+An example's doctest directives modify doctest's behavior for that single
+example. Use ``+`` to enable the named behavior, or ``-`` to disable it.
+
+For example, this test passes::
+
+ >>> print range(20) #doctest: +NORMALIZE_WHITESPACE
+ [0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 10, 11, 12, 13, 14, 15, 16, 17, 18, 19]
+
+Without the directive it would fail, both because the actual output doesn't have
+two blanks before the single-digit list elements, and because the actual output
+is on a single line. This test also passes, and also requires a directive to do
+so::
+
+ >>> print range(20) # doctest:+ELLIPSIS
+ [0, 1, ..., 18, 19]
+
+Multiple directives can be used on a single physical line, separated by commas::
+
+ >>> print range(20) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ [0, 1, ..., 18, 19]
+
+If multiple directive comments are used for a single example, then they are
+combined::
+
+ >>> print range(20) # doctest: +ELLIPSIS
+ ... # doctest: +NORMALIZE_WHITESPACE
+ [0, 1, ..., 18, 19]
+
+As the previous example shows, you can add ``...`` lines to your example
+containing only directives. This can be useful when an example is too long for
+a directive to comfortably fit on the same line::
+
+ >>> print range(5) + range(10,20) + range(30,40) + range(50,60)
+ ... # doctest: +ELLIPSIS
+ [0, ..., 4, 10, ..., 19, 30, ..., 39, 50, ..., 59]
+
+Note that since all options are disabled by default, and directives apply only
+to the example they appear in, enabling options (via ``+`` in a directive) is
+usually the only meaningful choice. However, option flags can also be passed to
+functions that run doctests, establishing different defaults. In such cases,
+disabling an option via ``-`` in a directive can be useful.
+
+.. versionchanged:: 2.4
+ Constants :const:`DONT_ACCEPT_BLANKLINE`, :const:`NORMALIZE_WHITESPACE`,
+ :const:`ELLIPSIS`, :const:`IGNORE_EXCEPTION_DETAIL`, :const:`REPORT_UDIFF`,
+ :const:`REPORT_CDIFF`, :const:`REPORT_NDIFF`,
+ :const:`REPORT_ONLY_FIRST_FAILURE`, :const:`COMPARISON_FLAGS` and
+ :const:`REPORTING_FLAGS` were added; by default ``<BLANKLINE>`` in expected
+ output matches an empty line in actual output; and doctest directives were
+ added.
+
+.. versionchanged:: 2.5
+ Constant :const:`SKIP` was added.
+
+There's also a way to register new option flag names, although this isn't useful
+unless you intend to extend :mod:`doctest` internals via subclassing:
+
+
+.. function:: register_optionflag(name)
+
+ Create a new option flag with a given name, and return the new flag's integer
+ value. :func:`register_optionflag` can be used when subclassing
+ :class:`OutputChecker` or :class:`DocTestRunner` to create new options that are
+ supported by your subclasses. :func:`register_optionflag` should always be
+ called using the following idiom::
+
+ MY_FLAG = register_optionflag('MY_FLAG')
+
+ .. versionadded:: 2.4
+
+
+.. _doctest-warnings:
+
+Warnings
+^^^^^^^^
+
+:mod:`doctest` is serious about requiring exact matches in expected output. If
+even a single character doesn't match, the test fails. This will probably
+surprise you a few times, as you learn exactly what Python does and doesn't
+guarantee about output. For example, when printing a dict, Python doesn't
+guarantee that the key-value pairs will be printed in any particular order, so a
+test like
+
+.. % Hey! What happened to Monty Python examples?
+.. % Tim: ask Guido -- it's his example!
+
+::
+
+ >>> foo()
+ {"Hermione": "hippogryph", "Harry": "broomstick"}
+
+is vulnerable! One workaround is to do ::
+
+ >>> foo() == {"Hermione": "hippogryph", "Harry": "broomstick"}
+ True
+
+instead. Another is to do ::
+
+ >>> d = foo().items()
+ >>> d.sort()
+ >>> d
+ [('Harry', 'broomstick'), ('Hermione', 'hippogryph')]
+
+There are others, but you get the idea.
+
+Another bad idea is to print things that embed an object address, like ::
+
+ >>> id(1.0) # certain to fail some of the time
+ 7948648
+ >>> class C: pass
+ >>> C() # the default repr() for instances embeds an address
+ <__main__.C instance at 0x00AC18F0>
+
+The :const:`ELLIPSIS` directive gives a nice approach for the last example::
+
+ >>> C() #doctest: +ELLIPSIS
+ <__main__.C instance at 0x...>
+
+Floating-point numbers are also subject to small output variations across
+platforms, because Python defers to the platform C library for float formatting,
+and C libraries vary widely in quality here. ::
+
+ >>> 1./7 # risky
+ 0.14285714285714285
+ >>> print 1./7 # safer
+ 0.142857142857
+ >>> print round(1./7, 6) # much safer
+ 0.142857
+
+Numbers of the form ``I/2.**J`` are safe across all platforms, and I often
+contrive doctest examples to produce numbers of that form::
+
+ >>> 3./4 # utterly safe
+ 0.75
+
+Simple fractions are also easier for people to understand, and that makes for
+better documentation.
+
+
+.. _doctest-basic-api:
+
+Basic API
+---------
+
+The functions :func:`testmod` and :func:`testfile` provide a simple interface to
+doctest that should be sufficient for most basic uses. For a less formal
+introduction to these two functions, see sections :ref:`doctest-simple-testmod`
+and :ref:`doctest-simple-testfile`.
+
+
+.. function:: testfile(filename[, module_relative][, name][, package][, globs][, verbose][, report][, optionflags][, extraglobs][, raise_on_error][, parser][, encoding])
+
+ All arguments except *filename* are optional, and should be specified in keyword
+ form.
+
+ Test examples in the file named *filename*. Return ``(failure_count,
+ test_count)``.
+
+ Optional argument *module_relative* specifies how the filename should be
+ interpreted:
+
+ * If *module_relative* is ``True`` (the default), then *filename* specifies an
+ OS-independent module-relative path. By default, this path is relative to the
+ calling module's directory; but if the *package* argument is specified, then it
+ is relative to that package. To ensure OS-independence, *filename* should use
+ ``/`` characters to separate path segments, and may not be an absolute path
+ (i.e., it may not begin with ``/``).
+
+ * If *module_relative* is ``False``, then *filename* specifies an OS-specific
+ path. The path may be absolute or relative; relative paths are resolved with
+ respect to the current working directory.
+
+ Optional argument *name* gives the name of the test; by default, or if ``None``,
+ ``os.path.basename(filename)`` is used.
+
+ Optional argument *package* is a Python package or the name of a Python package
+ whose directory should be used as the base directory for a module-relative
+ filename. If no package is specified, then the calling module's directory is
+ used as the base directory for module-relative filenames. It is an error to
+ specify *package* if *module_relative* is ``False``.
+
+ Optional argument *globs* gives a dict to be used as the globals when executing
+ examples. A new shallow copy of this dict is created for the doctest, so its
+ examples start with a clean slate. By default, or if ``None``, a new empty dict
+ is used.
+
+ Optional argument *extraglobs* gives a dict merged into the globals used to
+ execute examples. This works like :meth:`dict.update`: if *globs* and
+ *extraglobs* have a common key, the associated value in *extraglobs* appears in
+ the combined dict. By default, or if ``None``, no extra globals are used. This
+ is an advanced feature that allows parameterization of doctests. For example, a
+ doctest can be written for a base class, using a generic name for the class,
+ then reused to test any number of subclasses by passing an *extraglobs* dict
+ mapping the generic name to the subclass to be tested.
+
+ Optional argument *verbose* prints lots of stuff if true, and prints only
+ failures if false; by default, or if ``None``, it's true if and only if ``'-v'``
+ is in ``sys.argv``.
+
+ Optional argument *report* prints a summary at the end when true, else prints
+ nothing at the end. In verbose mode, the summary is detailed, else the summary
+ is very brief (in fact, empty if all tests passed).
+
+ Optional argument *optionflags* or's together option flags. See section
+ :ref:`doctest-options`.
+
+ Optional argument *raise_on_error* defaults to false. If true, an exception is
+ raised upon the first failure or unexpected exception in an example. This
+ allows failures to be post-mortem debugged. Default behavior is to continue
+ running examples.
+
+ Optional argument *parser* specifies a :class:`DocTestParser` (or subclass) that
+ should be used to extract tests from the files. It defaults to a normal parser
+ (i.e., ``DocTestParser()``).
+
+ Optional argument *encoding* specifies an encoding that should be used to
+ convert the file to unicode.
+
+ .. versionadded:: 2.4
+
+ .. versionchanged:: 2.5
+ The parameter *encoding* was added.
+
+
+.. function:: testmod([m][, name][, globs][, verbose][, report][, optionflags][, extraglobs][, raise_on_error][, exclude_empty])
+
+ All arguments are optional, and all except for *m* should be specified in
+ keyword form.
+
+ Test examples in docstrings in functions and classes reachable from module *m*
+ (or module :mod:`__main__` if *m* is not supplied or is ``None``), starting with
+ ``m.__doc__``.
+
+ Also test examples reachable from dict ``m.__test__``, if it exists and is not
+ ``None``. ``m.__test__`` maps names (strings) to functions, classes and
+ strings; function and class docstrings are searched for examples; strings are
+ searched directly, as if they were docstrings.
+
+ Only docstrings attached to objects belonging to module *m* are searched.
+
+ Return ``(failure_count, test_count)``.
+
+ Optional argument *name* gives the name of the module; by default, or if
+ ``None``, ``m.__name__`` is used.
+
+ Optional argument *exclude_empty* defaults to false. If true, objects for which
+ no doctests are found are excluded from consideration. The default is a backward
+ compatibility hack, so that code still using :meth:`doctest.master.summarize` in
+ conjunction with :func:`testmod` continues to get output for objects with no
+ tests. The *exclude_empty* argument to the newer :class:`DocTestFinder`
+ constructor defaults to true.
+
+ Optional arguments *extraglobs*, *verbose*, *report*, *optionflags*,
+ *raise_on_error*, and *globs* are the same as for function :func:`testfile`
+ above, except that *globs* defaults to ``m.__dict__``.
+
+ .. versionchanged:: 2.3
+ The parameter *optionflags* was added.
+
+ .. versionchanged:: 2.4
+ The parameters *extraglobs*, *raise_on_error* and *exclude_empty* were added.
+
+ .. versionchanged:: 2.5
+ The optional argument *isprivate*, deprecated in 2.4, was removed.
+
+There's also a function to run the doctests associated with a single object.
+This function is provided for backward compatibility. There are no plans to
+deprecate it, but it's rarely useful:
+
+
+.. function:: run_docstring_examples(f, globs[, verbose][, name][, compileflags][, optionflags])
+
+ Test examples associated with object *f*; for example, *f* may be a module,
+ function, or class object.
+
+ A shallow copy of dictionary argument *globs* is used for the execution context.
+
+ Optional argument *name* is used in failure messages, and defaults to
+ ``"NoName"``.
+
+ If optional argument *verbose* is true, output is generated even if there are no
+ failures. By default, output is generated only in case of an example failure.
+
+ Optional argument *compileflags* gives the set of flags that should be used by
+ the Python compiler when running the examples. By default, or if ``None``,
+ flags are deduced corresponding to the set of future features found in *globs*.
+
+ Optional argument *optionflags* works as for function :func:`testfile` above.
+
+
+.. _doctest-unittest-api:
+
+Unittest API
+------------
+
+As your collection of doctest'ed modules grows, you'll want a way to run all
+their doctests systematically. Prior to Python 2.4, :mod:`doctest` had a barely
+documented :class:`Tester` class that supplied a rudimentary way to combine
+doctests from multiple modules. :class:`Tester` was feeble, and in practice most
+serious Python testing frameworks build on the :mod:`unittest` module, which
+supplies many flexible ways to combine tests from multiple sources. So, in
+Python 2.4, :mod:`doctest`'s :class:`Tester` class is deprecated, and
+:mod:`doctest` provides two functions that can be used to create :mod:`unittest`
+test suites from modules and text files containing doctests. These test suites
+can then be run using :mod:`unittest` test runners::
+
+ import unittest
+ import doctest
+ import my_module_with_doctests, and_another
+
+ suite = unittest.TestSuite()
+ for mod in my_module_with_doctests, and_another:
+ suite.addTest(doctest.DocTestSuite(mod))
+ runner = unittest.TextTestRunner()
+ runner.run(suite)
+
+There are two main functions for creating :class:`unittest.TestSuite` instances
+from text files and modules with doctests:
+
+
+.. function:: DocFileSuite([module_relative][, package][, setUp][, tearDown][, globs][, optionflags][, parser][, encoding])
+
+ Convert doctest tests from one or more text files to a
+ :class:`unittest.TestSuite`.
+
+ The returned :class:`unittest.TestSuite` is to be run by the unittest framework
+ and runs the interactive examples in each file. If an example in any file
+ fails, then the synthesized unit test fails, and a :exc:`failureException`
+ exception is raised showing the name of the file containing the test and a
+ (sometimes approximate) line number.
+
+ Pass one or more paths (as strings) to text files to be examined.
+
+ Options may be provided as keyword arguments:
+
+ Optional argument *module_relative* specifies how the filenames in *paths*
+ should be interpreted:
+
+ * If *module_relative* is ``True`` (the default), then each filename specifies
+ an OS-independent module-relative path. By default, this path is relative to
+ the calling module's directory; but if the *package* argument is specified, then
+ it is relative to that package. To ensure OS-independence, each filename should
+ use ``/`` characters to separate path segments, and may not be an absolute path
+ (i.e., it may not begin with ``/``).
+
+ * If *module_relative* is ``False``, then each filename specifies an OS-specific
+ path. The path may be absolute or relative; relative paths are resolved with
+ respect to the current working directory.
+
+ Optional argument *package* is a Python package or the name of a Python package
+ whose directory should be used as the base directory for module-relative
+ filenames. If no package is specified, then the calling module's directory is
+ used as the base directory for module-relative filenames. It is an error to
+ specify *package* if *module_relative* is ``False``.
+
+ Optional argument *setUp* specifies a set-up function for the test suite. This
+ is called before running the tests in each file. The *setUp* function will be
+ passed a :class:`DocTest` object. The setUp function can access the test
+ globals as the *globs* attribute of the test passed.
+
+ Optional argument *tearDown* specifies a tear-down function for the test suite.
+ This is called after running the tests in each file. The *tearDown* function
+ will be passed a :class:`DocTest` object. The setUp function can access the
+ test globals as the *globs* attribute of the test passed.
+
+ Optional argument *globs* is a dictionary containing the initial global
+ variables for the tests. A new copy of this dictionary is created for each
+ test. By default, *globs* is a new empty dictionary.
+
+ Optional argument *optionflags* specifies the default doctest options for the
+ tests, created by or-ing together individual option flags. See section
+ :ref:`doctest-options`. See function :func:`set_unittest_reportflags` below for
+ a better way to set reporting options.
+
+ Optional argument *parser* specifies a :class:`DocTestParser` (or subclass) that
+ should be used to extract tests from the files. It defaults to a normal parser
+ (i.e., ``DocTestParser()``).
+
+ Optional argument *encoding* specifies an encoding that should be used to
+ convert the file to unicode.
+
+ .. versionadded:: 2.4
+
+ .. versionchanged:: 2.5
+ The global ``__file__`` was added to the globals provided to doctests loaded
+ from a text file using :func:`DocFileSuite`.
+
+ .. versionchanged:: 2.5
+ The parameter *encoding* was added.
+
+
+.. function:: DocTestSuite([module][, globs][, extraglobs][, test_finder][, setUp][, tearDown][, checker])
+
+ Convert doctest tests for a module to a :class:`unittest.TestSuite`.
+
+ The returned :class:`unittest.TestSuite` is to be run by the unittest framework
+ and runs each doctest in the module. If any of the doctests fail, then the
+ synthesized unit test fails, and a :exc:`failureException` exception is raised
+ showing the name of the file containing the test and a (sometimes approximate)
+ line number.
+
+ Optional argument *module* provides the module to be tested. It can be a module
+ object or a (possibly dotted) module name. If not specified, the module calling
+ this function is used.
+
+ Optional argument *globs* is a dictionary containing the initial global
+ variables for the tests. A new copy of this dictionary is created for each
+ test. By default, *globs* is a new empty dictionary.
+
+ Optional argument *extraglobs* specifies an extra set of global variables, which
+ is merged into *globs*. By default, no extra globals are used.
+
+ Optional argument *test_finder* is the :class:`DocTestFinder` object (or a
+ drop-in replacement) that is used to extract doctests from the module.
+
+ Optional arguments *setUp*, *tearDown*, and *optionflags* are the same as for
+ function :func:`DocFileSuite` above.
+
+ .. versionadded:: 2.3
+
+ .. versionchanged:: 2.4
+ The parameters *globs*, *extraglobs*, *test_finder*, *setUp*, *tearDown*, and
+ *optionflags* were added; this function now uses the same search technique as
+ :func:`testmod`.
+
+Under the covers, :func:`DocTestSuite` creates a :class:`unittest.TestSuite` out
+of :class:`doctest.DocTestCase` instances, and :class:`DocTestCase` is a
+subclass of :class:`unittest.TestCase`. :class:`DocTestCase` isn't documented
+here (it's an internal detail), but studying its code can answer questions about
+the exact details of :mod:`unittest` integration.
+
+Similarly, :func:`DocFileSuite` creates a :class:`unittest.TestSuite` out of
+:class:`doctest.DocFileCase` instances, and :class:`DocFileCase` is a subclass
+of :class:`DocTestCase`.
+
+So both ways of creating a :class:`unittest.TestSuite` run instances of
+:class:`DocTestCase`. This is important for a subtle reason: when you run
+:mod:`doctest` functions yourself, you can control the :mod:`doctest` options in
+use directly, by passing option flags to :mod:`doctest` functions. However, if
+you're writing a :mod:`unittest` framework, :mod:`unittest` ultimately controls
+when and how tests get run. The framework author typically wants to control
+:mod:`doctest` reporting options (perhaps, e.g., specified by command line
+options), but there's no way to pass options through :mod:`unittest` to
+:mod:`doctest` test runners.
+
+For this reason, :mod:`doctest` also supports a notion of :mod:`doctest`
+reporting flags specific to :mod:`unittest` support, via this function:
+
+
+.. function:: set_unittest_reportflags(flags)
+
+ Set the :mod:`doctest` reporting flags to use.
+
+ Argument *flags* or's together option flags. See section
+ :ref:`doctest-options`. Only "reporting flags" can be used.
+
+ This is a module-global setting, and affects all future doctests run by module
+ :mod:`unittest`: the :meth:`runTest` method of :class:`DocTestCase` looks at
+ the option flags specified for the test case when the :class:`DocTestCase`
+ instance was constructed. If no reporting flags were specified (which is the
+ typical and expected case), :mod:`doctest`'s :mod:`unittest` reporting flags are
+ or'ed into the option flags, and the option flags so augmented are passed to the
+ :class:`DocTestRunner` instance created to run the doctest. If any reporting
+ flags were specified when the :class:`DocTestCase` instance was constructed,
+ :mod:`doctest`'s :mod:`unittest` reporting flags are ignored.
+
+ The value of the :mod:`unittest` reporting flags in effect before the function
+ was called is returned by the function.
+
+ .. versionadded:: 2.4
+
+
+.. _doctest-advanced-api:
+
+Advanced API
+------------
+
+The basic API is a simple wrapper that's intended to make doctest easy to use.
+It is fairly flexible, and should meet most users' needs; however, if you
+require more fine-grained control over testing, or wish to extend doctest's
+capabilities, then you should use the advanced API.
+
+The advanced API revolves around two container classes, which are used to store
+the interactive examples extracted from doctest cases:
+
+* :class:`Example`: A single python statement, paired with its expected output.
+
+* :class:`DocTest`: A collection of :class:`Example`\ s, typically extracted
+ from a single docstring or text file.
+
+Additional processing classes are defined to find, parse, and run, and check
+doctest examples:
+
+* :class:`DocTestFinder`: Finds all docstrings in a given module, and uses a
+ :class:`DocTestParser` to create a :class:`DocTest` from every docstring that
+ contains interactive examples.
+
+* :class:`DocTestParser`: Creates a :class:`DocTest` object from a string (such
+ as an object's docstring).
+
+* :class:`DocTestRunner`: Executes the examples in a :class:`DocTest`, and uses
+ an :class:`OutputChecker` to verify their output.
+
+* :class:`OutputChecker`: Compares the actual output from a doctest example with
+ the expected output, and decides whether they match.
+
+The relationships among these processing classes are summarized in the following
+diagram::
+
+ list of:
+ +------+ +---------+
+ |module| --DocTestFinder-> | DocTest | --DocTestRunner-> results
+ +------+ | ^ +---------+ | ^ (printed)
+ | | | Example | | |
+ v | | ... | v |
+ DocTestParser | Example | OutputChecker
+ +---------+
+
+
+.. _doctest-doctest:
+
+DocTest Objects
+^^^^^^^^^^^^^^^
+
+
+.. class:: DocTest(examples, globs, name, filename, lineno, docstring)
+
+ A collection of doctest examples that should be run in a single namespace. The
+ constructor arguments are used to initialize the member variables of the same
+ names.
+
+ .. versionadded:: 2.4
+
+:class:`DocTest` defines the following member variables. They are initialized
+by the constructor, and should not be modified directly.
+
+
+.. attribute:: DocTest.examples
+
+ A list of :class:`Example` objects encoding the individual interactive Python
+ examples that should be run by this test.
+
+
+.. attribute:: DocTest.globs
+
+ The namespace (aka globals) that the examples should be run in. This is a
+ dictionary mapping names to values. Any changes to the namespace made by the
+ examples (such as binding new variables) will be reflected in :attr:`globs`
+ after the test is run.
+
+
+.. attribute:: DocTest.name
+
+ A string name identifying the :class:`DocTest`. Typically, this is the name of
+ the object or file that the test was extracted from.
+
+
+.. attribute:: DocTest.filename
+
+ The name of the file that this :class:`DocTest` was extracted from; or ``None``
+ if the filename is unknown, or if the :class:`DocTest` was not extracted from a
+ file.
+
+
+.. attribute:: DocTest.lineno
+
+ The line number within :attr:`filename` where this :class:`DocTest` begins, or
+ ``None`` if the line number is unavailable. This line number is zero-based with
+ respect to the beginning of the file.
+
+
+.. attribute:: DocTest.docstring
+
+ The string that the test was extracted from, or 'None' if the string is
+ unavailable, or if the test was not extracted from a string.
+
+
+.. _doctest-example:
+
+Example Objects
+^^^^^^^^^^^^^^^
+
+
+.. class:: Example(source, want[, exc_msg][, lineno][, indent][, options])
+
+ A single interactive example, consisting of a Python statement and its expected
+ output. The constructor arguments are used to initialize the member variables
+ of the same names.
+
+ .. versionadded:: 2.4
+
+:class:`Example` defines the following member variables. They are initialized
+by the constructor, and should not be modified directly.
+
+
+.. attribute:: Example.source
+
+ A string containing the example's source code. This source code consists of a
+ single Python statement, and always ends with a newline; the constructor adds a
+ newline when necessary.
+
+
+.. attribute:: Example.want
+
+ The expected output from running the example's source code (either from stdout,
+ or a traceback in case of exception). :attr:`want` ends with a newline unless
+ no output is expected, in which case it's an empty string. The constructor adds
+ a newline when necessary.
+
+
+.. attribute:: Example.exc_msg
+
+ The exception message generated by the example, if the example is expected to
+ generate an exception; or ``None`` if it is not expected to generate an
+ exception. This exception message is compared against the return value of
+ :func:`traceback.format_exception_only`. :attr:`exc_msg` ends with a newline
+ unless it's ``None``. The constructor adds a newline if needed.
+
+
+.. attribute:: Example.lineno
+
+ The line number within the string containing this example where the example
+ begins. This line number is zero-based with respect to the beginning of the
+ containing string.
+
+
+.. attribute:: Example.indent
+
+ The example's indentation in the containing string, i.e., the number of space
+ characters that precede the example's first prompt.
+
+
+.. attribute:: Example.options
+
+ A dictionary mapping from option flags to ``True`` or ``False``, which is used
+ to override default options for this example. Any option flags not contained in
+ this dictionary are left at their default value (as specified by the
+ :class:`DocTestRunner`'s :attr:`optionflags`). By default, no options are set.
+
+
+.. _doctest-doctestfinder:
+
+DocTestFinder objects
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: DocTestFinder([verbose][, parser][, recurse][, exclude_empty])
+
+ A processing class used to extract the :class:`DocTest`\ s that are relevant to
+ a given object, from its docstring and the docstrings of its contained objects.
+ :class:`DocTest`\ s can currently be extracted from the following object types:
+ modules, functions, classes, methods, staticmethods, classmethods, and
+ properties.
+
+ The optional argument *verbose* can be used to display the objects searched by
+ the finder. It defaults to ``False`` (no output).
+
+ The optional argument *parser* specifies the :class:`DocTestParser` object (or a
+ drop-in replacement) that is used to extract doctests from docstrings.
+
+ If the optional argument *recurse* is false, then :meth:`DocTestFinder.find`
+ will only examine the given object, and not any contained objects.
+
+ If the optional argument *exclude_empty* is false, then
+ :meth:`DocTestFinder.find` will include tests for objects with empty docstrings.
+
+ .. versionadded:: 2.4
+
+:class:`DocTestFinder` defines the following method:
+
+
+.. method:: DocTestFinder.find(obj[, name][, module][, globs][, extraglobs])
+
+ Return a list of the :class:`DocTest`\ s that are defined by *obj*'s docstring,
+ or by any of its contained objects' docstrings.
+
+ The optional argument *name* specifies the object's name; this name will be used
+ to construct names for the returned :class:`DocTest`\ s. If *name* is not
+ specified, then ``obj.__name__`` is used.
+
+ The optional parameter *module* is the module that contains the given object.
+ If the module is not specified or is None, then the test finder will attempt to
+ automatically determine the correct module. The object's module is used:
+
+ * As a default namespace, if *globs* is not specified.
+
+ * To prevent the DocTestFinder from extracting DocTests from objects that are
+ imported from other modules. (Contained objects with modules other than
+ *module* are ignored.)
+
+ * To find the name of the file containing the object.
+
+ * To help find the line number of the object within its file.
+
+ If *module* is ``False``, no attempt to find the module will be made. This is
+ obscure, of use mostly in testing doctest itself: if *module* is ``False``, or
+ is ``None`` but cannot be found automatically, then all objects are considered
+ to belong to the (non-existent) module, so all contained objects will
+ (recursively) be searched for doctests.
+
+ The globals for each :class:`DocTest` is formed by combining *globs* and
+ *extraglobs* (bindings in *extraglobs* override bindings in *globs*). A new
+ shallow copy of the globals dictionary is created for each :class:`DocTest`. If
+ *globs* is not specified, then it defaults to the module's *__dict__*, if
+ specified, or ``{}`` otherwise. If *extraglobs* is not specified, then it
+ defaults to ``{}``.
+
+
+.. _doctest-doctestparser:
+
+DocTestParser objects
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: DocTestParser()
+
+ A processing class used to extract interactive examples from a string, and use
+ them to create a :class:`DocTest` object.
+
+ .. versionadded:: 2.4
+
+:class:`DocTestParser` defines the following methods:
+
+
+.. method:: DocTestParser.get_doctest(string, globs, name, filename, lineno)
+
+ Extract all doctest examples from the given string, and collect them into a
+ :class:`DocTest` object.
+
+ *globs*, *name*, *filename*, and *lineno* are attributes for the new
+ :class:`DocTest` object. See the documentation for :class:`DocTest` for more
+ information.
+
+
+.. method:: DocTestParser.get_examples(string[, name])
+
+ Extract all doctest examples from the given string, and return them as a list of
+ :class:`Example` objects. Line numbers are 0-based. The optional argument
+ *name* is a name identifying this string, and is only used for error messages.
+
+
+.. method:: DocTestParser.parse(string[, name])
+
+ Divide the given string into examples and intervening text, and return them as a
+ list of alternating :class:`Example`\ s and strings. Line numbers for the
+ :class:`Example`\ s are 0-based. The optional argument *name* is a name
+ identifying this string, and is only used for error messages.
+
+
+.. _doctest-doctestrunner:
+
+DocTestRunner objects
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: DocTestRunner([checker][, verbose][, optionflags])
+
+ A processing class used to execute and verify the interactive examples in a
+ :class:`DocTest`.
+
+ The comparison between expected outputs and actual outputs is done by an
+ :class:`OutputChecker`. This comparison may be customized with a number of
+ option flags; see section :ref:`doctest-options` for more information. If the
+ option flags are insufficient, then the comparison may also be customized by
+ passing a subclass of :class:`OutputChecker` to the constructor.
+
+ The test runner's display output can be controlled in two ways. First, an output
+ function can be passed to :meth:`TestRunner.run`; this function will be called
+ with strings that should be displayed. It defaults to ``sys.stdout.write``. If
+ capturing the output is not sufficient, then the display output can be also
+ customized by subclassing DocTestRunner, and overriding the methods
+ :meth:`report_start`, :meth:`report_success`,
+ :meth:`report_unexpected_exception`, and :meth:`report_failure`.
+
+ The optional keyword argument *checker* specifies the :class:`OutputChecker`
+ object (or drop-in replacement) that should be used to compare the expected
+ outputs to the actual outputs of doctest examples.
+
+ The optional keyword argument *verbose* controls the :class:`DocTestRunner`'s
+ verbosity. If *verbose* is ``True``, then information is printed about each
+ example, as it is run. If *verbose* is ``False``, then only failures are
+ printed. If *verbose* is unspecified, or ``None``, then verbose output is used
+ iff the command-line switch :option:`-v` is used.
+
+ The optional keyword argument *optionflags* can be used to control how the test
+ runner compares expected output to actual output, and how it displays failures.
+ For more information, see section :ref:`doctest-options`.
+
+ .. versionadded:: 2.4
+
+:class:`DocTestParser` defines the following methods:
+
+
+.. method:: DocTestRunner.report_start(out, test, example)
+
+ Report that the test runner is about to process the given example. This method
+ is provided to allow subclasses of :class:`DocTestRunner` to customize their
+ output; it should not be called directly.
+
+ *example* is the example about to be processed. *test* is the test containing
+ *example*. *out* is the output function that was passed to
+ :meth:`DocTestRunner.run`.
+
+
+.. method:: DocTestRunner.report_success(out, test, example, got)
+
+ Report that the given example ran successfully. This method is provided to
+ allow subclasses of :class:`DocTestRunner` to customize their output; it should
+ not be called directly.
+
+ *example* is the example about to be processed. *got* is the actual output from
+ the example. *test* is the test containing *example*. *out* is the output
+ function that was passed to :meth:`DocTestRunner.run`.
+
+
+.. method:: DocTestRunner.report_failure(out, test, example, got)
+
+ Report that the given example failed. This method is provided to allow
+ subclasses of :class:`DocTestRunner` to customize their output; it should not be
+ called directly.
+
+ *example* is the example about to be processed. *got* is the actual output from
+ the example. *test* is the test containing *example*. *out* is the output
+ function that was passed to :meth:`DocTestRunner.run`.
+
+
+.. method:: DocTestRunner.report_unexpected_exception(out, test, example, exc_info)
+
+ Report that the given example raised an unexpected exception. This method is
+ provided to allow subclasses of :class:`DocTestRunner` to customize their
+ output; it should not be called directly.
+
+ *example* is the example about to be processed. *exc_info* is a tuple containing
+ information about the unexpected exception (as returned by
+ :func:`sys.exc_info`). *test* is the test containing *example*. *out* is the
+ output function that was passed to :meth:`DocTestRunner.run`.
+
+
+.. method:: DocTestRunner.run(test[, compileflags][, out][, clear_globs])
+
+ Run the examples in *test* (a :class:`DocTest` object), and display the results
+ using the writer function *out*.
+
+ The examples are run in the namespace ``test.globs``. If *clear_globs* is true
+ (the default), then this namespace will be cleared after the test runs, to help
+ with garbage collection. If you would like to examine the namespace after the
+ test completes, then use *clear_globs=False*.
+
+ *compileflags* gives the set of flags that should be used by the Python compiler
+ when running the examples. If not specified, then it will default to the set of
+ future-import flags that apply to *globs*.
+
+ The output of each example is checked using the :class:`DocTestRunner`'s output
+ checker, and the results are formatted by the :meth:`DocTestRunner.report_\*`
+ methods.
+
+
+.. method:: DocTestRunner.summarize([verbose])
+
+ Print a summary of all the test cases that have been run by this DocTestRunner,
+ and return a tuple ``(failure_count, test_count)``.
+
+ The optional *verbose* argument controls how detailed the summary is. If the
+ verbosity is not specified, then the :class:`DocTestRunner`'s verbosity is used.
+
+
+.. _doctest-outputchecker:
+
+OutputChecker objects
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: OutputChecker()
+
+ A class used to check the whether the actual output from a doctest example
+ matches the expected output. :class:`OutputChecker` defines two methods:
+ :meth:`check_output`, which compares a given pair of outputs, and returns true
+ if they match; and :meth:`output_difference`, which returns a string describing
+ the differences between two outputs.
+
+ .. versionadded:: 2.4
+
+:class:`OutputChecker` defines the following methods:
+
+
+.. method:: OutputChecker.check_output(want, got, optionflags)
+
+ Return ``True`` iff the actual output from an example (*got*) matches the
+ expected output (*want*). These strings are always considered to match if they
+ are identical; but depending on what option flags the test runner is using,
+ several non-exact match types are also possible. See section
+ :ref:`doctest-options` for more information about option flags.
+
+
+.. method:: OutputChecker.output_difference(example, got, optionflags)
+
+ Return a string describing the differences between the expected output for a
+ given example (*example*) and the actual output (*got*). *optionflags* is the
+ set of option flags used to compare *want* and *got*.
+
+
+.. _doctest-debugging:
+
+Debugging
+---------
+
+Doctest provides several mechanisms for debugging doctest examples:
+
+* Several functions convert doctests to executable Python programs, which can be
+ run under the Python debugger, :mod:`pdb`.
+
+* The :class:`DebugRunner` class is a subclass of :class:`DocTestRunner` that
+ raises an exception for the first failing example, containing information about
+ that example. This information can be used to perform post-mortem debugging on
+ the example.
+
+* The :mod:`unittest` cases generated by :func:`DocTestSuite` support the
+ :meth:`debug` method defined by :class:`unittest.TestCase`.
+
+* You can add a call to :func:`pdb.set_trace` in a doctest example, and you'll
+ drop into the Python debugger when that line is executed. Then you can inspect
+ current values of variables, and so on. For example, suppose :file:`a.py`
+ contains just this module docstring::
+
+ """
+ >>> def f(x):
+ ... g(x*2)
+ >>> def g(x):
+ ... print x+3
+ ... import pdb; pdb.set_trace()
+ >>> f(3)
+ 9
+ """
+
+ Then an interactive Python session may look like this::
+
+ >>> import a, doctest
+ >>> doctest.testmod(a)
+ --Return--
+ > <doctest a[1]>(3)g()->None
+ -> import pdb; pdb.set_trace()
+ (Pdb) list
+ 1 def g(x):
+ 2 print x+3
+ 3 -> import pdb; pdb.set_trace()
+ [EOF]
+ (Pdb) print x
+ 6
+ (Pdb) step
+ --Return--
+ > <doctest a[0]>(2)f()->None
+ -> g(x*2)
+ (Pdb) list
+ 1 def f(x):
+ 2 -> g(x*2)
+ [EOF]
+ (Pdb) print x
+ 3
+ (Pdb) step
+ --Return--
+ > <doctest a[2]>(1)?()->None
+ -> f(3)
+ (Pdb) cont
+ (0, 3)
+ >>>
+
+ .. versionchanged:: 2.4
+ The ability to use :func:`pdb.set_trace` usefully inside doctests was added.
+
+Functions that convert doctests to Python code, and possibly run the synthesized
+code under the debugger:
+
+
+.. function:: script_from_examples(s)
+
+ Convert text with examples to a script.
+
+ Argument *s* is a string containing doctest examples. The string is converted
+ to a Python script, where doctest examples in *s* are converted to regular code,
+ and everything else is converted to Python comments. The generated script is
+ returned as a string. For example, ::
+
+ import doctest
+ print doctest.script_from_examples(r"""
+ Set x and y to 1 and 2.
+ >>> x, y = 1, 2
+
+ Print their sum:
+ >>> print x+y
+ 3
+ """)
+
+ displays::
+
+ # Set x and y to 1 and 2.
+ x, y = 1, 2
+ #
+ # Print their sum:
+ print x+y
+ # Expected:
+ ## 3
+
+ This function is used internally by other functions (see below), but can also be
+ useful when you want to transform an interactive Python session into a Python
+ script.
+
+ .. versionadded:: 2.4
+
+
+.. function:: testsource(module, name)
+
+ Convert the doctest for an object to a script.
+
+ Argument *module* is a module object, or dotted name of a module, containing the
+ object whose doctests are of interest. Argument *name* is the name (within the
+ module) of the object with the doctests of interest. The result is a string,
+ containing the object's docstring converted to a Python script, as described for
+ :func:`script_from_examples` above. For example, if module :file:`a.py`
+ contains a top-level function :func:`f`, then ::
+
+ import a, doctest
+ print doctest.testsource(a, "a.f")
+
+ prints a script version of function :func:`f`'s docstring, with doctests
+ converted to code, and the rest placed in comments.
+
+ .. versionadded:: 2.3
+
+
+.. function:: debug(module, name[, pm])
+
+ Debug the doctests for an object.
+
+ The *module* and *name* arguments are the same as for function
+ :func:`testsource` above. The synthesized Python script for the named object's
+ docstring is written to a temporary file, and then that file is run under the
+ control of the Python debugger, :mod:`pdb`.
+
+ A shallow copy of ``module.__dict__`` is used for both local and global
+ execution context.
+
+ Optional argument *pm* controls whether post-mortem debugging is used. If *pm*
+ has a true value, the script file is run directly, and the debugger gets
+ involved only if the script terminates via raising an unhandled exception. If
+ it does, then post-mortem debugging is invoked, via :func:`pdb.post_mortem`,
+ passing the traceback object from the unhandled exception. If *pm* is not
+ specified, or is false, the script is run under the debugger from the start, via
+ passing an appropriate :func:`exec` call to :func:`pdb.run`.
+
+ .. versionadded:: 2.3
+
+ .. versionchanged:: 2.4
+ The *pm* argument was added.
+
+
+.. function:: debug_src(src[, pm][, globs])
+
+ Debug the doctests in a string.
+
+ This is like function :func:`debug` above, except that a string containing
+ doctest examples is specified directly, via the *src* argument.
+
+ Optional argument *pm* has the same meaning as in function :func:`debug` above.
+
+ Optional argument *globs* gives a dictionary to use as both local and global
+ execution context. If not specified, or ``None``, an empty dictionary is used.
+ If specified, a shallow copy of the dictionary is used.
+
+ .. versionadded:: 2.4
+
+The :class:`DebugRunner` class, and the special exceptions it may raise, are of
+most interest to testing framework authors, and will only be sketched here. See
+the source code, and especially :class:`DebugRunner`'s docstring (which is a
+doctest!) for more details:
+
+
+.. class:: DebugRunner([checker][, verbose][, optionflags])
+
+ A subclass of :class:`DocTestRunner` that raises an exception as soon as a
+ failure is encountered. If an unexpected exception occurs, an
+ :exc:`UnexpectedException` exception is raised, containing the test, the
+ example, and the original exception. If the output doesn't match, then a
+ :exc:`DocTestFailure` exception is raised, containing the test, the example, and
+ the actual output.
+
+ For information about the constructor parameters and methods, see the
+ documentation for :class:`DocTestRunner` in section :ref:`doctest-advanced-api`.
+
+There are two exceptions that may be raised by :class:`DebugRunner` instances:
+
+
+.. exception:: DocTestFailure(test, example, got)
+
+ An exception thrown by :class:`DocTestRunner` to signal that a doctest example's
+ actual output did not match its expected output. The constructor arguments are
+ used to initialize the member variables of the same names.
+
+:exc:`DocTestFailure` defines the following member variables:
+
+
+.. attribute:: DocTestFailure.test
+
+ The :class:`DocTest` object that was being run when the example failed.
+
+
+.. attribute:: DocTestFailure.example
+
+ The :class:`Example` that failed.
+
+
+.. attribute:: DocTestFailure.got
+
+ The example's actual output.
+
+
+.. exception:: UnexpectedException(test, example, exc_info)
+
+ An exception thrown by :class:`DocTestRunner` to signal that a doctest example
+ raised an unexpected exception. The constructor arguments are used to
+ initialize the member variables of the same names.
+
+:exc:`UnexpectedException` defines the following member variables:
+
+
+.. attribute:: UnexpectedException.test
+
+ The :class:`DocTest` object that was being run when the example failed.
+
+
+.. attribute:: UnexpectedException.example
+
+ The :class:`Example` that failed.
+
+
+.. attribute:: UnexpectedException.exc_info
+
+ A tuple containing information about the unexpected exception, as returned by
+ :func:`sys.exc_info`.
+
+
+.. _doctest-soapbox:
+
+Soapbox
+-------
+
+As mentioned in the introduction, :mod:`doctest` has grown to have three primary
+uses:
+
+#. Checking examples in docstrings.
+
+#. Regression testing.
+
+#. Executable documentation / literate testing.
+
+These uses have different requirements, and it is important to distinguish them.
+In particular, filling your docstrings with obscure test cases makes for bad
+documentation.
+
+When writing a docstring, choose docstring examples with care. There's an art to
+this that needs to be learned---it may not be natural at first. Examples should
+add genuine value to the documentation. A good example can often be worth many
+words. If done with care, the examples will be invaluable for your users, and
+will pay back the time it takes to collect them many times over as the years go
+by and things change. I'm still amazed at how often one of my :mod:`doctest`
+examples stops working after a "harmless" change.
+
+Doctest also makes an excellent tool for regression testing, especially if you
+don't skimp on explanatory text. By interleaving prose and examples, it becomes
+much easier to keep track of what's actually being tested, and why. When a test
+fails, good prose can make it much easier to figure out what the problem is, and
+how it should be fixed. It's true that you could write extensive comments in
+code-based testing, but few programmers do. Many have found that using doctest
+approaches instead leads to much clearer tests. Perhaps this is simply because
+doctest makes writing prose a little easier than writing code, while writing
+comments in code is a little harder. I think it goes deeper than just that:
+the natural attitude when writing a doctest-based test is that you want to
+explain the fine points of your software, and illustrate them with examples.
+This in turn naturally leads to test files that start with the simplest
+features, and logically progress to complications and edge cases. A coherent
+narrative is the result, instead of a collection of isolated functions that test
+isolated bits of functionality seemingly at random. It's a different attitude,
+and produces different results, blurring the distinction between testing and
+explaining.
+
+Regression testing is best confined to dedicated objects or files. There are
+several options for organizing tests:
+
+* Write text files containing test cases as interactive examples, and test the
+ files using :func:`testfile` or :func:`DocFileSuite`. This is recommended,
+ although is easiest to do for new projects, designed from the start to use
+ doctest.
+
+* Define functions named ``_regrtest_topic`` that consist of single docstrings,
+ containing test cases for the named topics. These functions can be included in
+ the same file as the module, or separated out into a separate test file.
+
+* Define a ``__test__`` dictionary mapping from regression test topics to
+ docstrings containing test cases.
+
+.. rubric:: Footnotes
+
+.. [#] Examples containing both expected output and an exception are not supported.
+ Trying to guess where one ends and the other begins is too error-prone, and that
+ also makes for a confusing test.
+
diff --git a/Doc/library/docxmlrpcserver.rst b/Doc/library/docxmlrpcserver.rst
new file mode 100644
index 0000000000..958ea95854
--- /dev/null
+++ b/Doc/library/docxmlrpcserver.rst
@@ -0,0 +1,97 @@
+
+:mod:`DocXMLRPCServer` --- Self-documenting XML-RPC server
+==========================================================
+
+.. module:: DocXMLRPCServer
+ :synopsis: Self-documenting XML-RPC server implementation.
+.. moduleauthor:: Brian Quinlan <brianq@activestate.com>
+.. sectionauthor:: Brian Quinlan <brianq@activestate.com>
+
+
+.. versionadded:: 2.3
+
+The :mod:`DocXMLRPCServer` module extends the classes found in
+:mod:`SimpleXMLRPCServer` to serve HTML documentation in response to HTTP GET
+requests. Servers can either be free standing, using :class:`DocXMLRPCServer`,
+or embedded in a CGI environment, using :class:`DocCGIXMLRPCRequestHandler`.
+
+
+.. class:: DocXMLRPCServer(addr[, requestHandler[, logRequests[, allow_none[, encoding[, bind_and_activate]]]]])
+
+ Create a new server instance. All parameters have the same meaning as for
+ :class:`SimpleXMLRPCServer.SimpleXMLRPCServer`; *requestHandler* defaults to
+ :class:`DocXMLRPCRequestHandler`.
+
+
+.. class:: DocCGIXMLRPCRequestHandler()
+
+ Create a new instance to handle XML-RPC requests in a CGI environment.
+
+
+.. class:: DocXMLRPCRequestHandler()
+
+ Create a new request handler instance. This request handler supports XML-RPC
+ POST requests, documentation GET requests, and modifies logging so that the
+ *logRequests* parameter to the :class:`DocXMLRPCServer` constructor parameter is
+ honored.
+
+
+.. _doc-xmlrpc-servers:
+
+DocXMLRPCServer Objects
+-----------------------
+
+The :class:`DocXMLRPCServer` class is derived from
+:class:`SimpleXMLRPCServer.SimpleXMLRPCServer` and provides a means of creating
+self-documenting, stand alone XML-RPC servers. HTTP POST requests are handled as
+XML-RPC method calls. HTTP GET requests are handled by generating pydoc-style
+HTML documentation. This allows a server to provide its own web-based
+documentation.
+
+
+.. method:: DocXMLRPCServer.set_server_title(server_title)
+
+ Set the title used in the generated HTML documentation. This title will be used
+ inside the HTML "title" element.
+
+
+.. method:: DocXMLRPCServer.set_server_name(server_name)
+
+ Set the name used in the generated HTML documentation. This name will appear at
+ the top of the generated documentation inside a "h1" element.
+
+
+.. method:: DocXMLRPCServer.set_server_documentation(server_documentation)
+
+ Set the description used in the generated HTML documentation. This description
+ will appear as a paragraph, below the server name, in the documentation.
+
+
+DocCGIXMLRPCRequestHandler
+--------------------------
+
+The :class:`DocCGIXMLRPCRequestHandler` class is derived from
+:class:`SimpleXMLRPCServer.CGIXMLRPCRequestHandler` and provides a means of
+creating self-documenting, XML-RPC CGI scripts. HTTP POST requests are handled
+as XML-RPC method calls. HTTP GET requests are handled by generating pydoc-style
+HTML documentation. This allows a server to provide its own web-based
+documentation.
+
+
+.. method:: DocCGIXMLRPCRequestHandler.set_server_title(server_title)
+
+ Set the title used in the generated HTML documentation. This title will be used
+ inside the HTML "title" element.
+
+
+.. method:: DocCGIXMLRPCRequestHandler.set_server_name(server_name)
+
+ Set the name used in the generated HTML documentation. This name will appear at
+ the top of the generated documentation inside a "h1" element.
+
+
+.. method:: DocCGIXMLRPCRequestHandler.set_server_documentation(server_documentation)
+
+ Set the description used in the generated HTML documentation. This description
+ will appear as a paragraph, below the server name, in the documentation.
+
diff --git a/Doc/library/dumbdbm.rst b/Doc/library/dumbdbm.rst
new file mode 100644
index 0000000000..3db9fda7ce
--- /dev/null
+++ b/Doc/library/dumbdbm.rst
@@ -0,0 +1,81 @@
+
+:mod:`dumbdbm` --- Portable DBM implementation
+==============================================
+
+.. module:: dumbdbm
+ :synopsis: Portable implementation of the simple DBM interface.
+
+
+.. index:: single: databases
+
+.. note::
+
+ The :mod:`dumbdbm` module is intended as a last resort fallback for the
+ :mod:`anydbm` module when no more robust module is available. The :mod:`dumbdbm`
+ module is not written for speed and is not nearly as heavily used as the other
+ database modules.
+
+The :mod:`dumbdbm` module provides a persistent dictionary-like interface which
+is written entirely in Python. Unlike other modules such as :mod:`gdbm` and
+:mod:`bsddb`, no external library is required. As with other persistent
+mappings, the keys and values must always be strings.
+
+The module defines the following:
+
+
+.. exception:: error
+
+ Raised on dumbdbm-specific errors, such as I/O errors. :exc:`KeyError` is
+ raised for general mapping errors like specifying an incorrect key.
+
+
+.. function:: open(filename[, flag[, mode]])
+
+ Open a dumbdbm database and return a dumbdbm object. The *filename* argument is
+ the basename of the database file (without any specific extensions). When a
+ dumbdbm database is created, files with :file:`.dat` and :file:`.dir` extensions
+ are created.
+
+ The optional *flag* argument is currently ignored; the database is always opened
+ for update, and will be created if it does not exist.
+
+ The optional *mode* argument is the Unix mode of the file, used only when the
+ database has to be created. It defaults to octal ``0666`` (and will be modified
+ by the prevailing umask).
+
+ .. versionchanged:: 2.2
+ The *mode* argument was ignored in earlier versions.
+
+
+.. seealso::
+
+ Module :mod:`anydbm`
+ Generic interface to ``dbm``\ -style databases.
+
+ Module :mod:`dbm`
+ Similar interface to the DBM/NDBM library.
+
+ Module :mod:`gdbm`
+ Similar interface to the GNU GDBM library.
+
+ Module :mod:`shelve`
+ Persistence module which stores non-string data.
+
+ Module :mod:`whichdb`
+ Utility module used to determine the type of an existing database.
+
+
+.. _dumbdbm-objects:
+
+Dumbdbm Objects
+---------------
+
+In addition to the methods provided by the :class:`UserDict.DictMixin` class,
+:class:`dumbdbm` objects provide the following methods.
+
+
+.. method:: dumbdbm.sync()
+
+ Synchronize the on-disk directory and data files. This method is called by the
+ :meth:`sync` method of :class:`Shelve` objects.
+
diff --git a/Doc/library/dummy_thread.rst b/Doc/library/dummy_thread.rst
new file mode 100644
index 0000000000..0b2cb179a6
--- /dev/null
+++ b/Doc/library/dummy_thread.rst
@@ -0,0 +1,23 @@
+
+:mod:`dummy_thread` --- Drop-in replacement for the :mod:`thread` module
+========================================================================
+
+.. module:: dummy_thread
+ :synopsis: Drop-in replacement for the thread module.
+
+
+This module provides a duplicate interface to the :mod:`thread` module. It is
+meant to be imported when the :mod:`thread` module is not provided on a
+platform.
+
+Suggested usage is::
+
+ try:
+ import thread as _thread
+ except ImportError:
+ import dummy_thread as _thread
+
+Be careful to not use this module where deadlock might occur from a thread
+being created that blocks waiting for another thread to be created. This often
+occurs with blocking I/O.
+
diff --git a/Doc/library/dummy_threading.rst b/Doc/library/dummy_threading.rst
new file mode 100644
index 0000000000..0ffb68732f
--- /dev/null
+++ b/Doc/library/dummy_threading.rst
@@ -0,0 +1,23 @@
+
+:mod:`dummy_threading` --- Drop-in replacement for the :mod:`threading` module
+==============================================================================
+
+.. module:: dummy_threading
+ :synopsis: Drop-in replacement for the threading module.
+
+
+This module provides a duplicate interface to the :mod:`threading` module. It
+is meant to be imported when the :mod:`thread` module is not provided on a
+platform.
+
+Suggested usage is::
+
+ try:
+ import threading as _threading
+ except ImportError:
+ import dummy_threading as _threading
+
+Be careful to not use this module where deadlock might occur from a thread
+being created that blocks waiting for another thread to be created. This often
+occurs with blocking I/O.
+
diff --git a/Doc/library/easydialogs.rst b/Doc/library/easydialogs.rst
new file mode 100644
index 0000000000..50b312fcb7
--- /dev/null
+++ b/Doc/library/easydialogs.rst
@@ -0,0 +1,207 @@
+
+:mod:`EasyDialogs` --- Basic Macintosh dialogs
+==============================================
+
+.. module:: EasyDialogs
+ :platform: Mac
+ :synopsis: Basic Macintosh dialogs.
+
+
+The :mod:`EasyDialogs` module contains some simple dialogs for the Macintosh.
+All routines take an optional resource ID parameter *id* with which one can
+override the :const:`DLOG` resource used for the dialog, provided that the
+dialog items correspond (both type and item number) to those in the default
+:const:`DLOG` resource. See source code for details.
+
+The :mod:`EasyDialogs` module defines the following functions:
+
+
+.. function:: Message(str[, id[, ok]])
+
+ Displays a modal dialog with the message text *str*, which should be at most 255
+ characters long. The button text defaults to "OK", but is set to the string
+ argument *ok* if the latter is supplied. Control is returned when the user
+ clicks the "OK" button.
+
+
+.. function:: AskString(prompt[, default[, id[, ok[, cancel]]]])
+
+ Asks the user to input a string value via a modal dialog. *prompt* is the prompt
+ message, and the optional *default* supplies the initial value for the string
+ (otherwise ``""`` is used). The text of the "OK" and "Cancel" buttons can be
+ changed with the *ok* and *cancel* arguments. All strings can be at most 255
+ bytes long. :func:`AskString` returns the string entered or :const:`None` in
+ case the user cancelled.
+
+
+.. function:: AskPassword(prompt[, default[, id[, ok[, cancel]]]])
+
+ Asks the user to input a string value via a modal dialog. Like
+ :func:`AskString`, but with the text shown as bullets. The arguments have the
+ same meaning as for :func:`AskString`.
+
+
+.. function:: AskYesNoCancel(question[, default[, yes[, no[, cancel[, id]]]]])
+
+ Presents a dialog with prompt *question* and three buttons labelled "Yes", "No",
+ and "Cancel". Returns ``1`` for "Yes", ``0`` for "No" and ``-1`` for "Cancel".
+ The value of *default* (or ``0`` if *default* is not supplied) is returned when
+ the :kbd:`RETURN` key is pressed. The text of the buttons can be changed with
+ the *yes*, *no*, and *cancel* arguments; to prevent a button from appearing,
+ supply ``""`` for the corresponding argument.
+
+
+.. function:: ProgressBar([title[, maxval[, label[, id]]]])
+
+ Displays a modeless progress-bar dialog. This is the constructor for the
+ :class:`ProgressBar` class described below. *title* is the text string displayed
+ (default "Working..."), *maxval* is the value at which progress is complete
+ (default ``0``, indicating that an indeterminate amount of work remains to be
+ done), and *label* is the text that is displayed above the progress bar itself.
+
+
+.. function:: GetArgv([optionlist[ commandlist[, addoldfile[, addnewfile[, addfolder[, id]]]]]])
+
+ Displays a dialog which aids the user in constructing a command-line argument
+ list. Returns the list in ``sys.argv`` format, suitable for passing as an
+ argument to :func:`getopt.getopt`. *addoldfile*, *addnewfile*, and *addfolder*
+ are boolean arguments. When nonzero, they enable the user to insert into the
+ command line paths to an existing file, a (possibly) not-yet-existent file, and
+ a folder, respectively. (Note: Option arguments must appear in the command line
+ before file and folder arguments in order to be recognized by
+ :func:`getopt.getopt`.) Arguments containing spaces can be specified by
+ enclosing them within single or double quotes. A :exc:`SystemExit` exception is
+ raised if the user presses the "Cancel" button.
+
+ *optionlist* is a list that determines a popup menu from which the allowed
+ options are selected. Its items can take one of two forms: *optstr* or
+ ``(optstr, descr)``. When present, *descr* is a short descriptive string that
+ is displayed in the dialog while this option is selected in the popup menu. The
+ correspondence between *optstr*\s and command-line arguments is:
+
+ +----------------------+------------------------------------------+
+ | *optstr* format | Command-line format |
+ +======================+==========================================+
+ | ``x`` | :option:`-x` (short option) |
+ +----------------------+------------------------------------------+
+ | ``x:`` or ``x=`` | :option:`-x` (short option with value) |
+ +----------------------+------------------------------------------+
+ | ``xyz`` | :option:`--xyz` (long option) |
+ +----------------------+------------------------------------------+
+ | ``xyz:`` or ``xyz=`` | :option:`--xyz` (long option with value) |
+ +----------------------+------------------------------------------+
+
+ *commandlist* is a list of items of the form *cmdstr* or ``(cmdstr, descr)``,
+ where *descr* is as above. The *cmdstr*s will appear in a popup menu. When
+ chosen, the text of *cmdstr* will be appended to the command line as is, except
+ that a trailing ``':'`` or ``'='`` (if present) will be trimmed off.
+
+ .. versionadded:: 2.0
+
+
+.. function:: AskFileForOpen( [message] [, typeList] [, defaultLocation] [, defaultOptionFlags] [, location] [, clientName] [, windowTitle] [, actionButtonLabel] [, cancelButtonLabel] [, preferenceKey] [, popupExtension] [, eventProc] [, previewProc] [, filterProc] [, wanted] )
+
+ Post a dialog asking the user for a file to open, and return the file selected
+ or :const:`None` if the user cancelled. *message* is a text message to display,
+ *typeList* is a list of 4-char filetypes allowable, *defaultLocation* is the
+ pathname, :class:`FSSpec` or :class:`FSRef` of the folder to show initially,
+ *location* is the ``(x, y)`` position on the screen where the dialog is shown,
+ *actionButtonLabel* is a string to show instead of "Open" in the OK button,
+ *cancelButtonLabel* is a string to show instead of "Cancel" in the cancel
+ button, *wanted* is the type of value wanted as a return: :class:`str`,
+ :class:`unicode`, :class:`FSSpec`, :class:`FSRef` and subtypes thereof are
+ acceptable.
+
+ .. index:: single: Navigation Services
+
+ For a description of the other arguments please see the Apple Navigation
+ Services documentation and the :mod:`EasyDialogs` source code.
+
+
+.. function:: AskFileForSave( [message] [, savedFileName] [, defaultLocation] [, defaultOptionFlags] [, location] [, clientName] [, windowTitle] [, actionButtonLabel] [, cancelButtonLabel] [, preferenceKey] [, popupExtension] [, fileType] [, fileCreator] [, eventProc] [, wanted] )
+
+ Post a dialog asking the user for a file to save to, and return the file
+ selected or :const:`None` if the user cancelled. *savedFileName* is the default
+ for the file name to save to (the return value). See :func:`AskFileForOpen` for
+ a description of the other arguments.
+
+
+.. function:: AskFolder( [message] [, defaultLocation] [, defaultOptionFlags] [, location] [, clientName] [, windowTitle] [, actionButtonLabel] [, cancelButtonLabel] [, preferenceKey] [, popupExtension] [, eventProc] [, filterProc] [, wanted] )
+
+ Post a dialog asking the user to select a folder, and return the folder selected
+ or :const:`None` if the user cancelled. See :func:`AskFileForOpen` for a
+ description of the arguments.
+
+
+.. seealso::
+
+ `Navigation Services Reference <http://developer.apple.com/documentation/Carbon/Reference/Navigation_Services_Ref/>`_
+ Programmer's reference documentation for the Navigation Services, a part of the
+ Carbon framework.
+
+
+.. _progressbar-objects:
+
+ProgressBar Objects
+-------------------
+
+:class:`ProgressBar` objects provide support for modeless progress-bar dialogs.
+Both determinate (thermometer style) and indeterminate (barber-pole style)
+progress bars are supported. The bar will be determinate if its maximum value
+is greater than zero; otherwise it will be indeterminate.
+
+.. versionchanged:: 2.2
+ Support for indeterminate-style progress bars was added.
+
+The dialog is displayed immediately after creation. If the dialog's "Cancel"
+button is pressed, or if :kbd:`Cmd-.` or :kbd:`ESC` is typed, the dialog window
+is hidden and :exc:`KeyboardInterrupt` is raised (but note that this response
+does not occur until the progress bar is next updated, typically via a call to
+:meth:`inc` or :meth:`set`). Otherwise, the bar remains visible until the
+:class:`ProgressBar` object is discarded.
+
+:class:`ProgressBar` objects possess the following attributes and methods:
+
+
+.. attribute:: ProgressBar.curval
+
+ The current value (of type integer or long integer) of the progress bar. The
+ normal access methods coerce :attr:`curval` between ``0`` and :attr:`maxval`.
+ This attribute should not be altered directly.
+
+
+.. attribute:: ProgressBar.maxval
+
+ The maximum value (of type integer or long integer) of the progress bar; the
+ progress bar (thermometer style) is full when :attr:`curval` equals
+ :attr:`maxval`. If :attr:`maxval` is ``0``, the bar will be indeterminate
+ (barber-pole). This attribute should not be altered directly.
+
+
+.. method:: ProgressBar.title([newstr])
+
+ Sets the text in the title bar of the progress dialog to *newstr*.
+
+
+.. method:: ProgressBar.label([newstr])
+
+ Sets the text in the progress box of the progress dialog to *newstr*.
+
+
+.. method:: ProgressBar.set(value[, max])
+
+ Sets the progress bar's :attr:`curval` to *value*, and also :attr:`maxval` to
+ *max* if the latter is provided. *value* is first coerced between 0 and
+ :attr:`maxval`. The thermometer bar is updated to reflect the changes,
+ including a change from indeterminate to determinate or vice versa.
+
+
+.. method:: ProgressBar.inc([n])
+
+ Increments the progress bar's :attr:`curval` by *n*, or by ``1`` if *n* is not
+ provided. (Note that *n* may be negative, in which case the effect is a
+ decrement.) The progress bar is updated to reflect the change. If the bar is
+ indeterminate, this causes one "spin" of the barber pole. The resulting
+ :attr:`curval` is coerced between 0 and :attr:`maxval` if incrementing causes it
+ to fall outside this range.
+
diff --git a/Doc/library/email-examples.rst b/Doc/library/email-examples.rst
new file mode 100644
index 0000000000..64a9944335
--- /dev/null
+++ b/Doc/library/email-examples.rst
@@ -0,0 +1,33 @@
+:mod:`email`: Examples
+----------------------
+
+Here are a few examples of how to use the :mod:`email` package to read, write,
+and send simple email messages, as well as more complex MIME messages.
+
+First, let's see how to create and send a simple text message:
+
+.. literalinclude:: ../includes/email-simple.py
+
+
+Here's an example of how to send a MIME message containing a bunch of family
+pictures that may be residing in a directory:
+
+.. literalinclude:: ../includes/email-mime.py
+
+
+Here's an example of how to send the entire contents of a directory as an email
+message: [1]_
+
+.. literalinclude:: ../includes/email-dir.py
+
+
+And finally, here's an example of how to unpack a MIME message like the one
+above, into a directory of files:
+
+.. literalinclude:: ../includes/email-unpack.py
+
+
+.. rubric:: Footnotes
+
+.. [1] Thanks to Matthew Dixon Cowles for the original inspiration and examples.
+
diff --git a/Doc/library/email.charset.rst b/Doc/library/email.charset.rst
new file mode 100644
index 0000000000..d16d2817b9
--- /dev/null
+++ b/Doc/library/email.charset.rst
@@ -0,0 +1,249 @@
+:mod:`email`: Representing character sets
+-----------------------------------------
+
+.. module:: email.charset
+ :synopsis: Character Sets
+
+
+This module provides a class :class:`Charset` for representing character sets
+and character set conversions in email messages, as well as a character set
+registry and several convenience methods for manipulating this registry.
+Instances of :class:`Charset` are used in several other modules within the
+:mod:`email` package.
+
+Import this class from the :mod:`email.charset` module.
+
+.. versionadded:: 2.2.2
+
+
+.. class:: Charset([input_charset])
+
+ Map character sets to their email properties.
+
+ This class provides information about the requirements imposed on email for a
+ specific character set. It also provides convenience routines for converting
+ between character sets, given the availability of the applicable codecs. Given
+ a character set, it will do its best to provide information on how to use that
+ character set in an email message in an RFC-compliant way.
+
+ Certain character sets must be encoded with quoted-printable or base64 when used
+ in email headers or bodies. Certain character sets must be converted outright,
+ and are not allowed in email.
+
+ Optional *input_charset* is as described below; it is always coerced to lower
+ case. After being alias normalized it is also used as a lookup into the
+ registry of character sets to find out the header encoding, body encoding, and
+ output conversion codec to be used for the character set. For example, if
+ *input_charset* is ``iso-8859-1``, then headers and bodies will be encoded using
+ quoted-printable and no output conversion codec is necessary. If
+ *input_charset* is ``euc-jp``, then headers will be encoded with base64, bodies
+ will not be encoded, but output text will be converted from the ``euc-jp``
+ character set to the ``iso-2022-jp`` character set.
+
+:class:`Charset` instances have the following data attributes:
+
+
+.. data:: input_charset
+
+ The initial character set specified. Common aliases are converted to their
+ *official* email names (e.g. ``latin_1`` is converted to ``iso-8859-1``).
+ Defaults to 7-bit ``us-ascii``.
+
+
+.. data:: header_encoding
+
+ If the character set must be encoded before it can be used in an email header,
+ this attribute will be set to ``Charset.QP`` (for quoted-printable),
+ ``Charset.BASE64`` (for base64 encoding), or ``Charset.SHORTEST`` for the
+ shortest of QP or BASE64 encoding. Otherwise, it will be ``None``.
+
+
+.. data:: body_encoding
+
+ Same as *header_encoding*, but describes the encoding for the mail message's
+ body, which indeed may be different than the header encoding.
+ ``Charset.SHORTEST`` is not allowed for *body_encoding*.
+
+
+.. data:: output_charset
+
+ Some character sets must be converted before they can be used in email headers
+ or bodies. If the *input_charset* is one of them, this attribute will contain
+ the name of the character set output will be converted to. Otherwise, it will
+ be ``None``.
+
+
+.. data:: input_codec
+
+ The name of the Python codec used to convert the *input_charset* to Unicode. If
+ no conversion codec is necessary, this attribute will be ``None``.
+
+
+.. data:: output_codec
+
+ The name of the Python codec used to convert Unicode to the *output_charset*.
+ If no conversion codec is necessary, this attribute will have the same value as
+ the *input_codec*.
+
+:class:`Charset` instances also have the following methods:
+
+
+.. method:: Charset.get_body_encoding()
+
+ Return the content transfer encoding used for body encoding.
+
+ This is either the string ``quoted-printable`` or ``base64`` depending on the
+ encoding used, or it is a function, in which case you should call the function
+ with a single argument, the Message object being encoded. The function should
+ then set the :mailheader:`Content-Transfer-Encoding` header itself to whatever
+ is appropriate.
+
+ Returns the string ``quoted-printable`` if *body_encoding* is ``QP``, returns
+ the string ``base64`` if *body_encoding* is ``BASE64``, and returns the string
+ ``7bit`` otherwise.
+
+
+.. method:: Charset.convert(s)
+
+ Convert the string *s* from the *input_codec* to the *output_codec*.
+
+
+.. method:: Charset.to_splittable(s)
+
+ Convert a possibly multibyte string to a safely splittable format. *s* is the
+ string to split.
+
+ Uses the *input_codec* to try and convert the string to Unicode, so it can be
+ safely split on character boundaries (even for multibyte characters).
+
+ Returns the string as-is if it isn't known how to convert *s* to Unicode with
+ the *input_charset*.
+
+ Characters that could not be converted to Unicode will be replaced with the
+ Unicode replacement character ``'U+FFFD'``.
+
+
+.. method:: Charset.from_splittable(ustr[, to_output])
+
+ Convert a splittable string back into an encoded string. *ustr* is a Unicode
+ string to "unsplit".
+
+ This method uses the proper codec to try and convert the string from Unicode
+ back into an encoded format. Return the string as-is if it is not Unicode, or
+ if it could not be converted from Unicode.
+
+ Characters that could not be converted from Unicode will be replaced with an
+ appropriate character (usually ``'?'``).
+
+ If *to_output* is ``True`` (the default), uses *output_codec* to convert to an
+ encoded format. If *to_output* is ``False``, it uses *input_codec*.
+
+
+.. method:: Charset.get_output_charset()
+
+ Return the output character set.
+
+ This is the *output_charset* attribute if that is not ``None``, otherwise it is
+ *input_charset*.
+
+
+.. method:: Charset.encoded_header_len()
+
+ Return the length of the encoded header string, properly calculating for
+ quoted-printable or base64 encoding.
+
+
+.. method:: Charset.header_encode(s[, convert])
+
+ Header-encode the string *s*.
+
+ If *convert* is ``True``, the string will be converted from the input charset to
+ the output charset automatically. This is not useful for multibyte character
+ sets, which have line length issues (multibyte characters must be split on a
+ character, not a byte boundary); use the higher-level :class:`Header` class to
+ deal with these issues (see :mod:`email.header`). *convert* defaults to
+ ``False``.
+
+ The type of encoding (base64 or quoted-printable) will be based on the
+ *header_encoding* attribute.
+
+
+.. method:: Charset.body_encode(s[, convert])
+
+ Body-encode the string *s*.
+
+ If *convert* is ``True`` (the default), the string will be converted from the
+ input charset to output charset automatically. Unlike :meth:`header_encode`,
+ there are no issues with byte boundaries and multibyte charsets in email bodies,
+ so this is usually pretty safe.
+
+ The type of encoding (base64 or quoted-printable) will be based on the
+ *body_encoding* attribute.
+
+The :class:`Charset` class also provides a number of methods to support standard
+operations and built-in functions.
+
+
+.. method:: Charset.__str__()
+
+ Returns *input_charset* as a string coerced to lower case. :meth:`__repr__` is
+ an alias for :meth:`__str__`.
+
+
+.. method:: Charset.__eq__(other)
+
+ This method allows you to compare two :class:`Charset` instances for equality.
+
+
+.. method:: Header.__ne__(other)
+
+ This method allows you to compare two :class:`Charset` instances for inequality.
+
+The :mod:`email.charset` module also provides the following functions for adding
+new entries to the global character set, alias, and codec registries:
+
+
+.. function:: add_charset(charset[, header_enc[, body_enc[, output_charset]]])
+
+ Add character properties to the global registry.
+
+ *charset* is the input character set, and must be the canonical name of a
+ character set.
+
+ Optional *header_enc* and *body_enc* is either ``Charset.QP`` for
+ quoted-printable, ``Charset.BASE64`` for base64 encoding,
+ ``Charset.SHORTEST`` for the shortest of quoted-printable or base64 encoding,
+ or ``None`` for no encoding. ``SHORTEST`` is only valid for
+ *header_enc*. The default is ``None`` for no encoding.
+
+ Optional *output_charset* is the character set that the output should be in.
+ Conversions will proceed from input charset, to Unicode, to the output charset
+ when the method :meth:`Charset.convert` is called. The default is to output in
+ the same character set as the input.
+
+ Both *input_charset* and *output_charset* must have Unicode codec entries in the
+ module's character set-to-codec mapping; use :func:`add_codec` to add codecs the
+ module does not know about. See the :mod:`codecs` module's documentation for
+ more information.
+
+ The global character set registry is kept in the module global dictionary
+ ``CHARSETS``.
+
+
+.. function:: add_alias(alias, canonical)
+
+ Add a character set alias. *alias* is the alias name, e.g. ``latin-1``.
+ *canonical* is the character set's canonical name, e.g. ``iso-8859-1``.
+
+ The global charset alias registry is kept in the module global dictionary
+ ``ALIASES``.
+
+
+.. function:: add_codec(charset, codecname)
+
+ Add a codec that map characters in the given character set to and from Unicode.
+
+ *charset* is the canonical name of a character set. *codecname* is the name of a
+ Python codec, as appropriate for the second argument to the :func:`unicode`
+ built-in, or to the :meth:`encode` method of a Unicode string.
+
diff --git a/Doc/library/email.encoders.rst b/Doc/library/email.encoders.rst
new file mode 100644
index 0000000000..28669c42cd
--- /dev/null
+++ b/Doc/library/email.encoders.rst
@@ -0,0 +1,57 @@
+:mod:`email`: Encoders
+----------------------
+
+.. module:: email.encoders
+ :synopsis: Encoders for email message payloads.
+
+
+When creating :class:`Message` objects from scratch, you often need to encode
+the payloads for transport through compliant mail servers. This is especially
+true for :mimetype:`image/\*` and :mimetype:`text/\*` type messages containing
+binary data.
+
+The :mod:`email` package provides some convenient encodings in its
+:mod:`encoders` module. These encoders are actually used by the
+:class:`MIMEAudio` and :class:`MIMEImage` class constructors to provide default
+encodings. All encoder functions take exactly one argument, the message object
+to encode. They usually extract the payload, encode it, and reset the payload
+to this newly encoded value. They should also set the
+:mailheader:`Content-Transfer-Encoding` header as appropriate.
+
+Here are the encoding functions provided:
+
+
+.. function:: encode_quopri(msg)
+
+ Encodes the payload into quoted-printable form and sets the
+ :mailheader:`Content-Transfer-Encoding` header to ``quoted-printable`` [#]_.
+ This is a good encoding to use when most of your payload is normal printable
+ data, but contains a few unprintable characters.
+
+
+.. function:: encode_base64(msg)
+
+ Encodes the payload into base64 form and sets the
+ :mailheader:`Content-Transfer-Encoding` header to ``base64``. This is a good
+ encoding to use when most of your payload is unprintable data since it is a more
+ compact form than quoted-printable. The drawback of base64 encoding is that it
+ renders the text non-human readable.
+
+
+.. function:: encode_7or8bit(msg)
+
+ This doesn't actually modify the message's payload, but it does set the
+ :mailheader:`Content-Transfer-Encoding` header to either ``7bit`` or ``8bit`` as
+ appropriate, based on the payload data.
+
+
+.. function:: encode_noop(msg)
+
+ This does nothing; it doesn't even set the
+ :mailheader:`Content-Transfer-Encoding` header.
+
+.. rubric:: Footnotes
+
+.. [#] Note that encoding with :meth:`encode_quopri` also encodes all tabs and space
+ characters in the data.
+
diff --git a/Doc/library/email.errors.rst b/Doc/library/email.errors.rst
new file mode 100644
index 0000000000..916d2a564e
--- /dev/null
+++ b/Doc/library/email.errors.rst
@@ -0,0 +1,91 @@
+:mod:`email`: Exception and Defect classes
+------------------------------------------
+
+.. module:: email.errors
+ :synopsis: The exception classes used by the email package.
+
+
+The following exception classes are defined in the :mod:`email.errors` module:
+
+
+.. exception:: MessageError()
+
+ This is the base class for all exceptions that the :mod:`email` package can
+ raise. It is derived from the standard :exc:`Exception` class and defines no
+ additional methods.
+
+
+.. exception:: MessageParseError()
+
+ This is the base class for exceptions thrown by the :class:`Parser` class. It
+ is derived from :exc:`MessageError`.
+
+
+.. exception:: HeaderParseError()
+
+ Raised under some error conditions when parsing the :rfc:`2822` headers of a
+ message, this class is derived from :exc:`MessageParseError`. It can be raised
+ from the :meth:`Parser.parse` or :meth:`Parser.parsestr` methods.
+
+ Situations where it can be raised include finding an envelope header after the
+ first :rfc:`2822` header of the message, finding a continuation line before the
+ first :rfc:`2822` header is found, or finding a line in the headers which is
+ neither a header or a continuation line.
+
+
+.. exception:: BoundaryError()
+
+ Raised under some error conditions when parsing the :rfc:`2822` headers of a
+ message, this class is derived from :exc:`MessageParseError`. It can be raised
+ from the :meth:`Parser.parse` or :meth:`Parser.parsestr` methods.
+
+ Situations where it can be raised include not being able to find the starting or
+ terminating boundary in a :mimetype:`multipart/\*` message when strict parsing
+ is used.
+
+
+.. exception:: MultipartConversionError()
+
+ Raised when a payload is added to a :class:`Message` object using
+ :meth:`add_payload`, but the payload is already a scalar and the message's
+ :mailheader:`Content-Type` main type is not either :mimetype:`multipart` or
+ missing. :exc:`MultipartConversionError` multiply inherits from
+ :exc:`MessageError` and the built-in :exc:`TypeError`.
+
+ Since :meth:`Message.add_payload` is deprecated, this exception is rarely raised
+ in practice. However the exception may also be raised if the :meth:`attach`
+ method is called on an instance of a class derived from
+ :class:`MIMENonMultipart` (e.g. :class:`MIMEImage`).
+
+Here's the list of the defects that the :class:`FeedParser` can find while
+parsing messages. Note that the defects are added to the message where the
+problem was found, so for example, if a message nested inside a
+:mimetype:`multipart/alternative` had a malformed header, that nested message
+object would have a defect, but the containing messages would not.
+
+All defect classes are subclassed from :class:`email.errors.MessageDefect`, but
+this class is *not* an exception!
+
+.. versionadded:: 2.4
+ All the defect classes were added.
+
+* :class:`NoBoundaryInMultipartDefect` -- A message claimed to be a multipart,
+ but had no :mimetype:`boundary` parameter.
+
+* :class:`StartBoundaryNotFoundDefect` -- The start boundary claimed in the
+ :mailheader:`Content-Type` header was never found.
+
+* :class:`FirstHeaderLineIsContinuationDefect` -- The message had a continuation
+ line as its first header line.
+
+* :class:`MisplacedEnvelopeHeaderDefect` - A "Unix From" header was found in the
+ middle of a header block.
+
+* :class:`MalformedHeaderDefect` -- A header was found that was missing a colon,
+ or was otherwise malformed.
+
+* :class:`MultipartInvariantViolationDefect` -- A message claimed to be a
+ :mimetype:`multipart`, but no subparts were found. Note that when a message has
+ this defect, its :meth:`is_multipart` method may return false even though its
+ content type claims to be :mimetype:`multipart`.
+
diff --git a/Doc/library/email.generator.rst b/Doc/library/email.generator.rst
new file mode 100644
index 0000000000..bb1f57d0df
--- /dev/null
+++ b/Doc/library/email.generator.rst
@@ -0,0 +1,123 @@
+:mod:`email`: Generating MIME documents
+---------------------------------------
+
+.. module:: email.generator
+ :synopsis: Generate flat text email messages from a message structure.
+
+
+One of the most common tasks is to generate the flat text of the email message
+represented by a message object structure. You will need to do this if you want
+to send your message via the :mod:`smtplib` module or the :mod:`nntplib` module,
+or print the message on the console. Taking a message object structure and
+producing a flat text document is the job of the :class:`Generator` class.
+
+Again, as with the :mod:`email.parser` module, you aren't limited to the
+functionality of the bundled generator; you could write one from scratch
+yourself. However the bundled generator knows how to generate most email in a
+standards-compliant way, should handle MIME and non-MIME email messages just
+fine, and is designed so that the transformation from flat text, to a message
+structure via the :class:`Parser` class, and back to flat text, is idempotent
+(the input is identical to the output).
+
+Here are the public methods of the :class:`Generator` class, imported from the
+:mod:`email.generator` module:
+
+
+.. class:: Generator(outfp[, mangle_from_[, maxheaderlen]])
+
+ The constructor for the :class:`Generator` class takes a file-like object called
+ *outfp* for an argument. *outfp* must support the :meth:`write` method and be
+ usable as the output file in a Python extended print statement.
+
+ Optional *mangle_from_* is a flag that, when ``True``, puts a ``>`` character in
+ front of any line in the body that starts exactly as ``From``, i.e. ``From``
+ followed by a space at the beginning of the line. This is the only guaranteed
+ portable way to avoid having such lines be mistaken for a Unix mailbox format
+ envelope header separator (see `WHY THE CONTENT-LENGTH FORMAT IS BAD
+ <http://www.jwz.org/doc/content-length.html>`_ for details). *mangle_from_*
+ defaults to ``True``, but you might want to set this to ``False`` if you are not
+ writing Unix mailbox format files.
+
+ Optional *maxheaderlen* specifies the longest length for a non-continued header.
+ When a header line is longer than *maxheaderlen* (in characters, with tabs
+ expanded to 8 spaces), the header will be split as defined in the
+ :mod:`email.header.Header` class. Set to zero to disable header wrapping. The
+ default is 78, as recommended (but not required) by :rfc:`2822`.
+
+The other public :class:`Generator` methods are:
+
+
+.. method:: Generator.flatten(msg[, unixfrom])
+
+ Print the textual representation of the message object structure rooted at *msg*
+ to the output file specified when the :class:`Generator` instance was created.
+ Subparts are visited depth-first and the resulting text will be properly MIME
+ encoded.
+
+ Optional *unixfrom* is a flag that forces the printing of the envelope header
+ delimiter before the first :rfc:`2822` header of the root message object. If
+ the root object has no envelope header, a standard one is crafted. By default,
+ this is set to ``False`` to inhibit the printing of the envelope delimiter.
+
+ Note that for subparts, no envelope header is ever printed.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Generator.clone(fp)
+
+ Return an independent clone of this :class:`Generator` instance with the exact
+ same options.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Generator.write(s)
+
+ Write the string *s* to the underlying file object, i.e. *outfp* passed to
+ :class:`Generator`'s constructor. This provides just enough file-like API for
+ :class:`Generator` instances to be used in extended print statements.
+
+As a convenience, see the methods :meth:`Message.as_string` and
+``str(aMessage)``, a.k.a. :meth:`Message.__str__`, which simplify the generation
+of a formatted string representation of a message object. For more detail, see
+:mod:`email.message`.
+
+The :mod:`email.generator` module also provides a derived class, called
+:class:`DecodedGenerator` which is like the :class:`Generator` base class,
+except that non-\ :mimetype:`text` parts are substituted with a format string
+representing the part.
+
+
+.. class:: DecodedGenerator(outfp[, mangle_from_[, maxheaderlen[, fmt]]])
+
+ This class, derived from :class:`Generator` walks through all the subparts of a
+ message. If the subpart is of main type :mimetype:`text`, then it prints the
+ decoded payload of the subpart. Optional *_mangle_from_* and *maxheaderlen* are
+ as with the :class:`Generator` base class.
+
+ If the subpart is not of main type :mimetype:`text`, optional *fmt* is a format
+ string that is used instead of the message payload. *fmt* is expanded with the
+ following keywords, ``%(keyword)s`` format:
+
+ * ``type`` -- Full MIME type of the non-\ :mimetype:`text` part
+
+ * ``maintype`` -- Main MIME type of the non-\ :mimetype:`text` part
+
+ * ``subtype`` -- Sub-MIME type of the non-\ :mimetype:`text` part
+
+ * ``filename`` -- Filename of the non-\ :mimetype:`text` part
+
+ * ``description`` -- Description associated with the non-\ :mimetype:`text` part
+
+ * ``encoding`` -- Content transfer encoding of the non-\ :mimetype:`text` part
+
+ The default value for *fmt* is ``None``, meaning ::
+
+ [Non-text (%(type)s) part of message omitted, filename %(filename)s]
+
+ .. versionadded:: 2.2.2
+
+.. versionchanged:: 2.5
+ The previously deprecated method :meth:`__call__` was removed.
+
diff --git a/Doc/library/email.header.rst b/Doc/library/email.header.rst
new file mode 100644
index 0000000000..0ecd35f502
--- /dev/null
+++ b/Doc/library/email.header.rst
@@ -0,0 +1,171 @@
+:mod:`email`: Internationalized headers
+---------------------------------------
+
+.. module:: email.header
+ :synopsis: Representing non-ASCII headers
+
+
+:rfc:`2822` is the base standard that describes the format of email messages.
+It derives from the older :rfc:`822` standard which came into widespread use at
+a time when most email was composed of ASCII characters only. :rfc:`2822` is a
+specification written assuming email contains only 7-bit ASCII characters.
+
+Of course, as email has been deployed worldwide, it has become
+internationalized, such that language specific character sets can now be used in
+email messages. The base standard still requires email messages to be
+transferred using only 7-bit ASCII characters, so a slew of RFCs have been
+written describing how to encode email containing non-ASCII characters into
+:rfc:`2822`\ -compliant format. These RFCs include :rfc:`2045`, :rfc:`2046`,
+:rfc:`2047`, and :rfc:`2231`. The :mod:`email` package supports these standards
+in its :mod:`email.header` and :mod:`email.charset` modules.
+
+If you want to include non-ASCII characters in your email headers, say in the
+:mailheader:`Subject` or :mailheader:`To` fields, you should use the
+:class:`Header` class and assign the field in the :class:`Message` object to an
+instance of :class:`Header` instead of using a string for the header value.
+Import the :class:`Header` class from the :mod:`email.header` module. For
+example::
+
+ >>> from email.message import Message
+ >>> from email.header import Header
+ >>> msg = Message()
+ >>> h = Header('p\xf6stal', 'iso-8859-1')
+ >>> msg['Subject'] = h
+ >>> print msg.as_string()
+ Subject: =?iso-8859-1?q?p=F6stal?=
+
+
+
+Notice here how we wanted the :mailheader:`Subject` field to contain a non-ASCII
+character? We did this by creating a :class:`Header` instance and passing in
+the character set that the byte string was encoded in. When the subsequent
+:class:`Message` instance was flattened, the :mailheader:`Subject` field was
+properly :rfc:`2047` encoded. MIME-aware mail readers would show this header
+using the embedded ISO-8859-1 character.
+
+.. versionadded:: 2.2.2
+
+Here is the :class:`Header` class description:
+
+
+.. class:: Header([s[, charset[, maxlinelen[, header_name[, continuation_ws[, errors]]]]]])
+
+ Create a MIME-compliant header that can contain strings in different character
+ sets.
+
+ Optional *s* is the initial header value. If ``None`` (the default), the
+ initial header value is not set. You can later append to the header with
+ :meth:`append` method calls. *s* may be a byte string or a Unicode string, but
+ see the :meth:`append` documentation for semantics.
+
+ Optional *charset* serves two purposes: it has the same meaning as the *charset*
+ argument to the :meth:`append` method. It also sets the default character set
+ for all subsequent :meth:`append` calls that omit the *charset* argument. If
+ *charset* is not provided in the constructor (the default), the ``us-ascii``
+ character set is used both as *s*'s initial charset and as the default for
+ subsequent :meth:`append` calls.
+
+ The maximum line length can be specified explicit via *maxlinelen*. For
+ splitting the first line to a shorter value (to account for the field header
+ which isn't included in *s*, e.g. :mailheader:`Subject`) pass in the name of the
+ field in *header_name*. The default *maxlinelen* is 76, and the default value
+ for *header_name* is ``None``, meaning it is not taken into account for the
+ first line of a long, split header.
+
+ Optional *continuation_ws* must be :rfc:`2822`\ -compliant folding whitespace,
+ and is usually either a space or a hard tab character. This character will be
+ prepended to continuation lines.
+
+Optional *errors* is passed straight through to the :meth:`append` method.
+
+
+.. method:: Header.append(s[, charset[, errors]])
+
+ Append the string *s* to the MIME header.
+
+ Optional *charset*, if given, should be a :class:`Charset` instance (see
+ :mod:`email.charset`) or the name of a character set, which will be converted to
+ a :class:`Charset` instance. A value of ``None`` (the default) means that the
+ *charset* given in the constructor is used.
+
+ *s* may be a byte string or a Unicode string. If it is a byte string (i.e.
+ ``isinstance(s, str)`` is true), then *charset* is the encoding of that byte
+ string, and a :exc:`UnicodeError` will be raised if the string cannot be decoded
+ with that character set.
+
+ If *s* is a Unicode string, then *charset* is a hint specifying the character
+ set of the characters in the string. In this case, when producing an
+ :rfc:`2822`\ -compliant header using :rfc:`2047` rules, the Unicode string will
+ be encoded using the following charsets in order: ``us-ascii``, the *charset*
+ hint, ``utf-8``. The first character set to not provoke a :exc:`UnicodeError`
+ is used.
+
+ Optional *errors* is passed through to any :func:`unicode` or
+ :func:`ustr.encode` call, and defaults to "strict".
+
+
+.. method:: Header.encode([splitchars])
+
+ Encode a message header into an RFC-compliant format, possibly wrapping long
+ lines and encapsulating non-ASCII parts in base64 or quoted-printable encodings.
+ Optional *splitchars* is a string containing characters to split long ASCII
+ lines on, in rough support of :rfc:`2822`'s *highest level syntactic breaks*.
+ This doesn't affect :rfc:`2047` encoded lines.
+
+The :class:`Header` class also provides a number of methods to support standard
+operators and built-in functions.
+
+
+.. method:: Header.__str__()
+
+ A synonym for :meth:`Header.encode`. Useful for ``str(aHeader)``.
+
+
+.. method:: Header.__unicode__()
+
+ A helper for the built-in :func:`unicode` function. Returns the header as a
+ Unicode string.
+
+
+.. method:: Header.__eq__(other)
+
+ This method allows you to compare two :class:`Header` instances for equality.
+
+
+.. method:: Header.__ne__(other)
+
+ This method allows you to compare two :class:`Header` instances for inequality.
+
+The :mod:`email.header` module also provides the following convenient functions.
+
+
+.. function:: decode_header(header)
+
+ Decode a message header value without converting the character set. The header
+ value is in *header*.
+
+ This function returns a list of ``(decoded_string, charset)`` pairs containing
+ each of the decoded parts of the header. *charset* is ``None`` for non-encoded
+ parts of the header, otherwise a lower case string containing the name of the
+ character set specified in the encoded string.
+
+ Here's an example::
+
+ >>> from email.header import decode_header
+ >>> decode_header('=?iso-8859-1?q?p=F6stal?=')
+ [('p\xf6stal', 'iso-8859-1')]
+
+
+.. function:: make_header(decoded_seq[, maxlinelen[, header_name[, continuation_ws]]])
+
+ Create a :class:`Header` instance from a sequence of pairs as returned by
+ :func:`decode_header`.
+
+ :func:`decode_header` takes a header value string and returns a sequence of
+ pairs of the format ``(decoded_string, charset)`` where *charset* is the name of
+ the character set.
+
+ This function takes one of those sequence of pairs and returns a :class:`Header`
+ instance. Optional *maxlinelen*, *header_name*, and *continuation_ws* are as in
+ the :class:`Header` constructor.
+
diff --git a/Doc/library/email.iterators.rst b/Doc/library/email.iterators.rst
new file mode 100644
index 0000000000..aa70141b2d
--- /dev/null
+++ b/Doc/library/email.iterators.rst
@@ -0,0 +1,65 @@
+:mod:`email`: Iterators
+-----------------------
+
+.. module:: email.iterators
+ :synopsis: Iterate over a message object tree.
+
+
+Iterating over a message object tree is fairly easy with the
+:meth:`Message.walk` method. The :mod:`email.iterators` module provides some
+useful higher level iterations over message object trees.
+
+
+.. function:: body_line_iterator(msg[, decode])
+
+ This iterates over all the payloads in all the subparts of *msg*, returning the
+ string payloads line-by-line. It skips over all the subpart headers, and it
+ skips over any subpart with a payload that isn't a Python string. This is
+ somewhat equivalent to reading the flat text representation of the message from
+ a file using :meth:`readline`, skipping over all the intervening headers.
+
+ Optional *decode* is passed through to :meth:`Message.get_payload`.
+
+
+.. function:: typed_subpart_iterator(msg[, maintype[, subtype]])
+
+ This iterates over all the subparts of *msg*, returning only those subparts that
+ match the MIME type specified by *maintype* and *subtype*.
+
+ Note that *subtype* is optional; if omitted, then subpart MIME type matching is
+ done only with the main type. *maintype* is optional too; it defaults to
+ :mimetype:`text`.
+
+ Thus, by default :func:`typed_subpart_iterator` returns each subpart that has a
+ MIME type of :mimetype:`text/\*`.
+
+The following function has been added as a useful debugging tool. It should
+*not* be considered part of the supported public interface for the package.
+
+
+.. function:: _structure(msg[, fp[, level]])
+
+ Prints an indented representation of the content types of the message object
+ structure. For example::
+
+ >>> msg = email.message_from_file(somefile)
+ >>> _structure(msg)
+ multipart/mixed
+ text/plain
+ text/plain
+ multipart/digest
+ message/rfc822
+ text/plain
+ message/rfc822
+ text/plain
+ message/rfc822
+ text/plain
+ message/rfc822
+ text/plain
+ message/rfc822
+ text/plain
+ text/plain
+
+ Optional *fp* is a file-like object to print the output to. It must be suitable
+ for Python's extended print statement. *level* is used internally.
+
diff --git a/Doc/library/email.message.rst b/Doc/library/email.message.rst
new file mode 100644
index 0000000000..e1fb20e357
--- /dev/null
+++ b/Doc/library/email.message.rst
@@ -0,0 +1,548 @@
+:mod:`email`: Representing an email message
+-------------------------------------------
+
+.. module:: email.message
+ :synopsis: The base class representing email messages.
+
+
+The central class in the :mod:`email` package is the :class:`Message` class,
+imported from the :mod:`email.message` module. It is the base class for the
+:mod:`email` object model. :class:`Message` provides the core functionality for
+setting and querying header fields, and for accessing message bodies.
+
+Conceptually, a :class:`Message` object consists of *headers* and *payloads*.
+Headers are :rfc:`2822` style field names and values where the field name and
+value are separated by a colon. The colon is not part of either the field name
+or the field value.
+
+Headers are stored and returned in case-preserving form but are matched
+case-insensitively. There may also be a single envelope header, also known as
+the *Unix-From* header or the ``From_`` header. The payload is either a string
+in the case of simple message objects or a list of :class:`Message` objects for
+MIME container documents (e.g. :mimetype:`multipart/\*` and
+:mimetype:`message/rfc822`).
+
+:class:`Message` objects provide a mapping style interface for accessing the
+message headers, and an explicit interface for accessing both the headers and
+the payload. It provides convenience methods for generating a flat text
+representation of the message object tree, for accessing commonly used header
+parameters, and for recursively walking over the object tree.
+
+Here are the methods of the :class:`Message` class:
+
+
+.. class:: Message()
+
+ The constructor takes no arguments.
+
+
+.. method:: Message.as_string([unixfrom])
+
+ Return the entire message flatten as a string. When optional *unixfrom* is
+ ``True``, the envelope header is included in the returned string. *unixfrom*
+ defaults to ``False``.
+
+ Note that this method is provided as a convenience and may not always format the
+ message the way you want. For example, by default it mangles lines that begin
+ with ``From``. For more flexibility, instantiate a :class:`Generator` instance
+ and use its :meth:`flatten` method directly. For example::
+
+ from cStringIO import StringIO
+ from email.generator import Generator
+ fp = StringIO()
+ g = Generator(fp, mangle_from_=False, maxheaderlen=60)
+ g.flatten(msg)
+ text = fp.getvalue()
+
+
+.. method:: Message.__str__()
+
+ Equivalent to ``as_string(unixfrom=True)``.
+
+
+.. method:: Message.is_multipart()
+
+ Return ``True`` if the message's payload is a list of sub-\ :class:`Message`
+ objects, otherwise return ``False``. When :meth:`is_multipart` returns False,
+ the payload should be a string object.
+
+
+.. method:: Message.set_unixfrom(unixfrom)
+
+ Set the message's envelope header to *unixfrom*, which should be a string.
+
+
+.. method:: Message.get_unixfrom()
+
+ Return the message's envelope header. Defaults to ``None`` if the envelope
+ header was never set.
+
+
+.. method:: Message.attach(payload)
+
+ Add the given *payload* to the current payload, which must be ``None`` or a list
+ of :class:`Message` objects before the call. After the call, the payload will
+ always be a list of :class:`Message` objects. If you want to set the payload to
+ a scalar object (e.g. a string), use :meth:`set_payload` instead.
+
+
+.. method:: Message.get_payload([i[, decode]])
+
+ Return a reference the current payload, which will be a list of :class:`Message`
+ objects when :meth:`is_multipart` is ``True``, or a string when
+ :meth:`is_multipart` is ``False``. If the payload is a list and you mutate the
+ list object, you modify the message's payload in place.
+
+ With optional argument *i*, :meth:`get_payload` will return the *i*-th element
+ of the payload, counting from zero, if :meth:`is_multipart` is ``True``. An
+ :exc:`IndexError` will be raised if *i* is less than 0 or greater than or equal
+ to the number of items in the payload. If the payload is a string (i.e.
+ :meth:`is_multipart` is ``False``) and *i* is given, a :exc:`TypeError` is
+ raised.
+
+ Optional *decode* is a flag indicating whether the payload should be decoded or
+ not, according to the :mailheader:`Content-Transfer-Encoding` header. When
+ ``True`` and the message is not a multipart, the payload will be decoded if this
+ header's value is ``quoted-printable`` or ``base64``. If some other encoding is
+ used, or :mailheader:`Content-Transfer-Encoding` header is missing, or if the
+ payload has bogus base64 data, the payload is returned as-is (undecoded). If
+ the message is a multipart and the *decode* flag is ``True``, then ``None`` is
+ returned. The default for *decode* is ``False``.
+
+
+.. method:: Message.set_payload(payload[, charset])
+
+ Set the entire message object's payload to *payload*. It is the client's
+ responsibility to ensure the payload invariants. Optional *charset* sets the
+ message's default character set; see :meth:`set_charset` for details.
+
+ .. versionchanged:: 2.2.2
+ *charset* argument added.
+
+
+.. method:: Message.set_charset(charset)
+
+ Set the character set of the payload to *charset*, which can either be a
+ :class:`Charset` instance (see :mod:`email.charset`), a string naming a
+ character set, or ``None``. If it is a string, it will be converted to a
+ :class:`Charset` instance. If *charset* is ``None``, the ``charset`` parameter
+ will be removed from the :mailheader:`Content-Type` header. Anything else will
+ generate a :exc:`TypeError`.
+
+ The message will be assumed to be of type :mimetype:`text/\*` encoded with
+ *charset.input_charset*. It will be converted to *charset.output_charset* and
+ encoded properly, if needed, when generating the plain text representation of
+ the message. MIME headers (:mailheader:`MIME-Version`,
+ :mailheader:`Content-Type`, :mailheader:`Content-Transfer-Encoding`) will be
+ added as needed.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_charset()
+
+ Return the :class:`Charset` instance associated with the message's payload.
+
+ .. versionadded:: 2.2.2
+
+The following methods implement a mapping-like interface for accessing the
+message's :rfc:`2822` headers. Note that there are some semantic differences
+between these methods and a normal mapping (i.e. dictionary) interface. For
+example, in a dictionary there are no duplicate keys, but here there may be
+duplicate message headers. Also, in dictionaries there is no guaranteed order
+to the keys returned by :meth:`keys`, but in a :class:`Message` object, headers
+are always returned in the order they appeared in the original message, or were
+added to the message later. Any header deleted and then re-added are always
+appended to the end of the header list.
+
+These semantic differences are intentional and are biased toward maximal
+convenience.
+
+Note that in all cases, any envelope header present in the message is not
+included in the mapping interface.
+
+
+.. method:: Message.__len__()
+
+ Return the total number of headers, including duplicates.
+
+
+.. method:: Message.__contains__(name)
+
+ Return true if the message object has a field named *name*. Matching is done
+ case-insensitively and *name* should not include the trailing colon. Used for
+ the ``in`` operator, e.g.::
+
+ if 'message-id' in myMessage:
+ print 'Message-ID:', myMessage['message-id']
+
+
+.. method:: Message.__getitem__(name)
+
+ Return the value of the named header field. *name* should not include the colon
+ field separator. If the header is missing, ``None`` is returned; a
+ :exc:`KeyError` is never raised.
+
+ Note that if the named field appears more than once in the message's headers,
+ exactly which of those field values will be returned is undefined. Use the
+ :meth:`get_all` method to get the values of all the extant named headers.
+
+
+.. method:: Message.__setitem__(name, val)
+
+ Add a header to the message with field name *name* and value *val*. The field
+ is appended to the end of the message's existing fields.
+
+ Note that this does *not* overwrite or delete any existing header with the same
+ name. If you want to ensure that the new header is the only one present in the
+ message with field name *name*, delete the field first, e.g.::
+
+ del msg['subject']
+ msg['subject'] = 'Python roolz!'
+
+
+.. method:: Message.__delitem__(name)
+
+ Delete all occurrences of the field with name *name* from the message's headers.
+ No exception is raised if the named field isn't present in the headers.
+
+
+.. method:: Message.has_key(name)
+
+ Return true if the message contains a header field named *name*, otherwise
+ return false.
+
+
+.. method:: Message.keys()
+
+ Return a list of all the message's header field names.
+
+
+.. method:: Message.values()
+
+ Return a list of all the message's field values.
+
+
+.. method:: Message.items()
+
+ Return a list of 2-tuples containing all the message's field headers and values.
+
+
+.. method:: Message.get(name[, failobj])
+
+ Return the value of the named header field. This is identical to
+ :meth:`__getitem__` except that optional *failobj* is returned if the named
+ header is missing (defaults to ``None``).
+
+Here are some additional useful methods:
+
+
+.. method:: Message.get_all(name[, failobj])
+
+ Return a list of all the values for the field named *name*. If there are no such
+ named headers in the message, *failobj* is returned (defaults to ``None``).
+
+
+.. method:: Message.add_header(_name, _value, **_params)
+
+ Extended header setting. This method is similar to :meth:`__setitem__` except
+ that additional header parameters can be provided as keyword arguments. *_name*
+ is the header field to add and *_value* is the *primary* value for the header.
+
+ For each item in the keyword argument dictionary *_params*, the key is taken as
+ the parameter name, with underscores converted to dashes (since dashes are
+ illegal in Python identifiers). Normally, the parameter will be added as
+ ``key="value"`` unless the value is ``None``, in which case only the key will be
+ added.
+
+ Here's an example::
+
+ msg.add_header('Content-Disposition', 'attachment', filename='bud.gif')
+
+ This will add a header that looks like ::
+
+ Content-Disposition: attachment; filename="bud.gif"
+
+
+.. method:: Message.replace_header(_name, _value)
+
+ Replace a header. Replace the first header found in the message that matches
+ *_name*, retaining header order and field name case. If no matching header was
+ found, a :exc:`KeyError` is raised.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_content_type()
+
+ Return the message's content type. The returned string is coerced to lower case
+ of the form :mimetype:`maintype/subtype`. If there was no
+ :mailheader:`Content-Type` header in the message the default type as given by
+ :meth:`get_default_type` will be returned. Since according to :rfc:`2045`,
+ messages always have a default type, :meth:`get_content_type` will always return
+ a value.
+
+ :rfc:`2045` defines a message's default type to be :mimetype:`text/plain` unless
+ it appears inside a :mimetype:`multipart/digest` container, in which case it
+ would be :mimetype:`message/rfc822`. If the :mailheader:`Content-Type` header
+ has an invalid type specification, :rfc:`2045` mandates that the default type be
+ :mimetype:`text/plain`.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_content_maintype()
+
+ Return the message's main content type. This is the :mimetype:`maintype` part
+ of the string returned by :meth:`get_content_type`.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_content_subtype()
+
+ Return the message's sub-content type. This is the :mimetype:`subtype` part of
+ the string returned by :meth:`get_content_type`.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_default_type()
+
+ Return the default content type. Most messages have a default content type of
+ :mimetype:`text/plain`, except for messages that are subparts of
+ :mimetype:`multipart/digest` containers. Such subparts have a default content
+ type of :mimetype:`message/rfc822`.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.set_default_type(ctype)
+
+ Set the default content type. *ctype* should either be :mimetype:`text/plain`
+ or :mimetype:`message/rfc822`, although this is not enforced. The default
+ content type is not stored in the :mailheader:`Content-Type` header.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_params([failobj[, header[, unquote]]])
+
+ Return the message's :mailheader:`Content-Type` parameters, as a list. The
+ elements of the returned list are 2-tuples of key/value pairs, as split on the
+ ``'='`` sign. The left hand side of the ``'='`` is the key, while the right
+ hand side is the value. If there is no ``'='`` sign in the parameter the value
+ is the empty string, otherwise the value is as described in :meth:`get_param`
+ and is unquoted if optional *unquote* is ``True`` (the default).
+
+ Optional *failobj* is the object to return if there is no
+ :mailheader:`Content-Type` header. Optional *header* is the header to search
+ instead of :mailheader:`Content-Type`.
+
+ .. versionchanged:: 2.2.2
+ *unquote* argument added.
+
+
+.. method:: Message.get_param(param[, failobj[, header[, unquote]]])
+
+ Return the value of the :mailheader:`Content-Type` header's parameter *param* as
+ a string. If the message has no :mailheader:`Content-Type` header or if there
+ is no such parameter, then *failobj* is returned (defaults to ``None``).
+
+ Optional *header* if given, specifies the message header to use instead of
+ :mailheader:`Content-Type`.
+
+ Parameter keys are always compared case insensitively. The return value can
+ either be a string, or a 3-tuple if the parameter was :rfc:`2231` encoded. When
+ it's a 3-tuple, the elements of the value are of the form ``(CHARSET, LANGUAGE,
+ VALUE)``. Note that both ``CHARSET`` and ``LANGUAGE`` can be ``None``, in which
+ case you should consider ``VALUE`` to be encoded in the ``us-ascii`` charset.
+ You can usually ignore ``LANGUAGE``.
+
+ If your application doesn't care whether the parameter was encoded as in
+ :rfc:`2231`, you can collapse the parameter value by calling
+ :func:`email.Utils.collapse_rfc2231_value`, passing in the return value from
+ :meth:`get_param`. This will return a suitably decoded Unicode string whn the
+ value is a tuple, or the original string unquoted if it isn't. For example::
+
+ rawparam = msg.get_param('foo')
+ param = email.Utils.collapse_rfc2231_value(rawparam)
+
+ In any case, the parameter value (either the returned string, or the ``VALUE``
+ item in the 3-tuple) is always unquoted, unless *unquote* is set to ``False``.
+
+ .. versionchanged:: 2.2.2
+ *unquote* argument added, and 3-tuple return value possible.
+
+
+.. method:: Message.set_param(param, value[, header[, requote[, charset[, language]]]])
+
+ Set a parameter in the :mailheader:`Content-Type` header. If the parameter
+ already exists in the header, its value will be replaced with *value*. If the
+ :mailheader:`Content-Type` header as not yet been defined for this message, it
+ will be set to :mimetype:`text/plain` and the new parameter value will be
+ appended as per :rfc:`2045`.
+
+ Optional *header* specifies an alternative header to :mailheader:`Content-Type`,
+ and all parameters will be quoted as necessary unless optional *requote* is
+ ``False`` (the default is ``True``).
+
+ If optional *charset* is specified, the parameter will be encoded according to
+ :rfc:`2231`. Optional *language* specifies the RFC 2231 language, defaulting to
+ the empty string. Both *charset* and *language* should be strings.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.del_param(param[, header[, requote]])
+
+ Remove the given parameter completely from the :mailheader:`Content-Type`
+ header. The header will be re-written in place without the parameter or its
+ value. All values will be quoted as necessary unless *requote* is ``False``
+ (the default is ``True``). Optional *header* specifies an alternative to
+ :mailheader:`Content-Type`.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.set_type(type[, header][, requote])
+
+ Set the main type and subtype for the :mailheader:`Content-Type` header. *type*
+ must be a string in the form :mimetype:`maintype/subtype`, otherwise a
+ :exc:`ValueError` is raised.
+
+ This method replaces the :mailheader:`Content-Type` header, keeping all the
+ parameters in place. If *requote* is ``False``, this leaves the existing
+ header's quoting as is, otherwise the parameters will be quoted (the default).
+
+ An alternative header can be specified in the *header* argument. When the
+ :mailheader:`Content-Type` header is set a :mailheader:`MIME-Version` header is
+ also added.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_filename([failobj])
+
+ Return the value of the ``filename`` parameter of the
+ :mailheader:`Content-Disposition` header of the message. If the header does not
+ have a ``filename`` parameter, this method falls back to looking for the
+ ``name`` parameter. If neither is found, or the header is missing, then
+ *failobj* is returned. The returned string will always be unquoted as per
+ :meth:`Utils.unquote`.
+
+
+.. method:: Message.get_boundary([failobj])
+
+ Return the value of the ``boundary`` parameter of the :mailheader:`Content-Type`
+ header of the message, or *failobj* if either the header is missing, or has no
+ ``boundary`` parameter. The returned string will always be unquoted as per
+ :meth:`Utils.unquote`.
+
+
+.. method:: Message.set_boundary(boundary)
+
+ Set the ``boundary`` parameter of the :mailheader:`Content-Type` header to
+ *boundary*. :meth:`set_boundary` will always quote *boundary* if necessary. A
+ :exc:`HeaderParseError` is raised if the message object has no
+ :mailheader:`Content-Type` header.
+
+ Note that using this method is subtly different than deleting the old
+ :mailheader:`Content-Type` header and adding a new one with the new boundary via
+ :meth:`add_header`, because :meth:`set_boundary` preserves the order of the
+ :mailheader:`Content-Type` header in the list of headers. However, it does *not*
+ preserve any continuation lines which may have been present in the original
+ :mailheader:`Content-Type` header.
+
+
+.. method:: Message.get_content_charset([failobj])
+
+ Return the ``charset`` parameter of the :mailheader:`Content-Type` header,
+ coerced to lower case. If there is no :mailheader:`Content-Type` header, or if
+ that header has no ``charset`` parameter, *failobj* is returned.
+
+ Note that this method differs from :meth:`get_charset` which returns the
+ :class:`Charset` instance for the default encoding of the message body.
+
+ .. versionadded:: 2.2.2
+
+
+.. method:: Message.get_charsets([failobj])
+
+ Return a list containing the character set names in the message. If the message
+ is a :mimetype:`multipart`, then the list will contain one element for each
+ subpart in the payload, otherwise, it will be a list of length 1.
+
+ Each item in the list will be a string which is the value of the ``charset``
+ parameter in the :mailheader:`Content-Type` header for the represented subpart.
+ However, if the subpart has no :mailheader:`Content-Type` header, no ``charset``
+ parameter, or is not of the :mimetype:`text` main MIME type, then that item in
+ the returned list will be *failobj*.
+
+
+.. method:: Message.walk()
+
+ The :meth:`walk` method is an all-purpose generator which can be used to iterate
+ over all the parts and subparts of a message object tree, in depth-first
+ traversal order. You will typically use :meth:`walk` as the iterator in a
+ ``for`` loop; each iteration returns the next subpart.
+
+ Here's an example that prints the MIME type of every part of a multipart message
+ structure::
+
+ >>> for part in msg.walk():
+ ... print part.get_content_type()
+ multipart/report
+ text/plain
+ message/delivery-status
+ text/plain
+ text/plain
+ message/rfc822
+
+.. versionchanged:: 2.5
+ The previously deprecated methods :meth:`get_type`, :meth:`get_main_type`, and
+ :meth:`get_subtype` were removed.
+
+:class:`Message` objects can also optionally contain two instance attributes,
+which can be used when generating the plain text of a MIME message.
+
+
+.. data:: preamble
+
+ The format of a MIME document allows for some text between the blank line
+ following the headers, and the first multipart boundary string. Normally, this
+ text is never visible in a MIME-aware mail reader because it falls outside the
+ standard MIME armor. However, when viewing the raw text of the message, or when
+ viewing the message in a non-MIME aware reader, this text can become visible.
+
+ The *preamble* attribute contains this leading extra-armor text for MIME
+ documents. When the :class:`Parser` discovers some text after the headers but
+ before the first boundary string, it assigns this text to the message's
+ *preamble* attribute. When the :class:`Generator` is writing out the plain text
+ representation of a MIME message, and it finds the message has a *preamble*
+ attribute, it will write this text in the area between the headers and the first
+ boundary. See :mod:`email.parser` and :mod:`email.generator` for details.
+
+ Note that if the message object has no preamble, the *preamble* attribute will
+ be ``None``.
+
+
+.. data:: epilogue
+
+ The *epilogue* attribute acts the same way as the *preamble* attribute, except
+ that it contains text that appears between the last boundary and the end of the
+ message.
+
+ .. versionchanged:: 2.5
+ You do not need to set the epilogue to the empty string in order for the
+ :class:`Generator` to print a newline at the end of the file.
+
+
+.. data:: defects
+
+ The *defects* attribute contains a list of all the problems found when parsing
+ this message. See :mod:`email.errors` for a detailed description of the
+ possible parsing defects.
+
+ .. versionadded:: 2.4
+
diff --git a/Doc/library/email.mime.rst b/Doc/library/email.mime.rst
new file mode 100644
index 0000000000..6f1b0aea98
--- /dev/null
+++ b/Doc/library/email.mime.rst
@@ -0,0 +1,175 @@
+:mod:`email`: Creating email and MIME objects from scratch
+----------------------------------------------------------
+
+.. module:: email.mime
+ :synopsis: Build MIME messages.
+
+
+Ordinarily, you get a message object structure by passing a file or some text to
+a parser, which parses the text and returns the root message object. However
+you can also build a complete message structure from scratch, or even individual
+:class:`Message` objects by hand. In fact, you can also take an existing
+structure and add new :class:`Message` objects, move them around, etc. This
+makes a very convenient interface for slicing-and-dicing MIME messages.
+
+You can create a new object structure by creating :class:`Message` instances,
+adding attachments and all the appropriate headers manually. For MIME messages
+though, the :mod:`email` package provides some convenient subclasses to make
+things easier.
+
+Here are the classes:
+
+
+.. class:: MIMEBase(_maintype, _subtype, **_params)
+
+ Module: :mod:`email.mime.base`
+
+ This is the base class for all the MIME-specific subclasses of :class:`Message`.
+ Ordinarily you won't create instances specifically of :class:`MIMEBase`,
+ although you could. :class:`MIMEBase` is provided primarily as a convenient
+ base class for more specific MIME-aware subclasses.
+
+ *_maintype* is the :mailheader:`Content-Type` major type (e.g. :mimetype:`text`
+ or :mimetype:`image`), and *_subtype* is the :mailheader:`Content-Type` minor
+ type (e.g. :mimetype:`plain` or :mimetype:`gif`). *_params* is a parameter
+ key/value dictionary and is passed directly to :meth:`Message.add_header`.
+
+ The :class:`MIMEBase` class always adds a :mailheader:`Content-Type` header
+ (based on *_maintype*, *_subtype*, and *_params*), and a
+ :mailheader:`MIME-Version` header (always set to ``1.0``).
+
+
+.. class:: MIMENonMultipart()
+
+ Module: :mod:`email.mime.nonmultipart`
+
+ A subclass of :class:`MIMEBase`, this is an intermediate base class for MIME
+ messages that are not :mimetype:`multipart`. The primary purpose of this class
+ is to prevent the use of the :meth:`attach` method, which only makes sense for
+ :mimetype:`multipart` messages. If :meth:`attach` is called, a
+ :exc:`MultipartConversionError` exception is raised.
+
+ .. versionadded:: 2.2.2
+
+
+.. class:: MIMEMultipart([subtype[, boundary[, _subparts[, _params]]]])
+
+ Module: :mod:`email.mime.multipart`
+
+ A subclass of :class:`MIMEBase`, this is an intermediate base class for MIME
+ messages that are :mimetype:`multipart`. Optional *_subtype* defaults to
+ :mimetype:`mixed`, but can be used to specify the subtype of the message. A
+ :mailheader:`Content-Type` header of :mimetype:`multipart/`*_subtype* will be
+ added to the message object. A :mailheader:`MIME-Version` header will also be
+ added.
+
+ Optional *boundary* is the multipart boundary string. When ``None`` (the
+ default), the boundary is calculated when needed.
+
+ *_subparts* is a sequence of initial subparts for the payload. It must be
+ possible to convert this sequence to a list. You can always attach new subparts
+ to the message by using the :meth:`Message.attach` method.
+
+ Additional parameters for the :mailheader:`Content-Type` header are taken from
+ the keyword arguments, or passed into the *_params* argument, which is a keyword
+ dictionary.
+
+ .. versionadded:: 2.2.2
+
+
+.. class:: MIMEApplication(_data[, _subtype[, _encoder[, **_params]]])
+
+ Module: :mod:`email.mime.application`
+
+ A subclass of :class:`MIMENonMultipart`, the :class:`MIMEApplication` class is
+ used to represent MIME message objects of major type :mimetype:`application`.
+ *_data* is a string containing the raw byte data. Optional *_subtype* specifies
+ the MIME subtype and defaults to :mimetype:`octet-stream`.
+
+ Optional *_encoder* is a callable (i.e. function) which will perform the actual
+ encoding of the data for transport. This callable takes one argument, which is
+ the :class:`MIMEApplication` instance. It should use :meth:`get_payload` and
+ :meth:`set_payload` to change the payload to encoded form. It should also add
+ any :mailheader:`Content-Transfer-Encoding` or other headers to the message
+ object as necessary. The default encoding is base64. See the
+ :mod:`email.encoders` module for a list of the built-in encoders.
+
+ *_params* are passed straight through to the base class constructor.
+
+ .. versionadded:: 2.5
+
+
+.. class:: MIMEAudio(_audiodata[, _subtype[, _encoder[, **_params]]])
+
+ Module: :mod:`email.mime.audio`
+
+ A subclass of :class:`MIMENonMultipart`, the :class:`MIMEAudio` class is used to
+ create MIME message objects of major type :mimetype:`audio`. *_audiodata* is a
+ string containing the raw audio data. If this data can be decoded by the
+ standard Python module :mod:`sndhdr`, then the subtype will be automatically
+ included in the :mailheader:`Content-Type` header. Otherwise you can explicitly
+ specify the audio subtype via the *_subtype* parameter. If the minor type could
+ not be guessed and *_subtype* was not given, then :exc:`TypeError` is raised.
+
+ Optional *_encoder* is a callable (i.e. function) which will perform the actual
+ encoding of the audio data for transport. This callable takes one argument,
+ which is the :class:`MIMEAudio` instance. It should use :meth:`get_payload` and
+ :meth:`set_payload` to change the payload to encoded form. It should also add
+ any :mailheader:`Content-Transfer-Encoding` or other headers to the message
+ object as necessary. The default encoding is base64. See the
+ :mod:`email.encoders` module for a list of the built-in encoders.
+
+ *_params* are passed straight through to the base class constructor.
+
+
+.. class:: MIMEImage(_imagedata[, _subtype[, _encoder[, **_params]]])
+
+ Module: :mod:`email.mime.image`
+
+ A subclass of :class:`MIMENonMultipart`, the :class:`MIMEImage` class is used to
+ create MIME message objects of major type :mimetype:`image`. *_imagedata* is a
+ string containing the raw image data. If this data can be decoded by the
+ standard Python module :mod:`imghdr`, then the subtype will be automatically
+ included in the :mailheader:`Content-Type` header. Otherwise you can explicitly
+ specify the image subtype via the *_subtype* parameter. If the minor type could
+ not be guessed and *_subtype* was not given, then :exc:`TypeError` is raised.
+
+ Optional *_encoder* is a callable (i.e. function) which will perform the actual
+ encoding of the image data for transport. This callable takes one argument,
+ which is the :class:`MIMEImage` instance. It should use :meth:`get_payload` and
+ :meth:`set_payload` to change the payload to encoded form. It should also add
+ any :mailheader:`Content-Transfer-Encoding` or other headers to the message
+ object as necessary. The default encoding is base64. See the
+ :mod:`email.encoders` module for a list of the built-in encoders.
+
+ *_params* are passed straight through to the :class:`MIMEBase` constructor.
+
+
+.. class:: MIMEMessage(_msg[, _subtype])
+
+ Module: :mod:`email.mime.message`
+
+ A subclass of :class:`MIMENonMultipart`, the :class:`MIMEMessage` class is used
+ to create MIME objects of main type :mimetype:`message`. *_msg* is used as the
+ payload, and must be an instance of class :class:`Message` (or a subclass
+ thereof), otherwise a :exc:`TypeError` is raised.
+
+ Optional *_subtype* sets the subtype of the message; it defaults to
+ :mimetype:`rfc822`.
+
+
+.. class:: MIMEText(_text[, _subtype[, _charset]])
+
+ Module: :mod:`email.mime.text`
+
+ A subclass of :class:`MIMENonMultipart`, the :class:`MIMEText` class is used to
+ create MIME objects of major type :mimetype:`text`. *_text* is the string for
+ the payload. *_subtype* is the minor type and defaults to :mimetype:`plain`.
+ *_charset* is the character set of the text and is passed as a parameter to the
+ :class:`MIMENonMultipart` constructor; it defaults to ``us-ascii``. No guessing
+ or encoding is performed on the text data.
+
+ .. versionchanged:: 2.4
+ The previously deprecated *_encoding* argument has been removed. Encoding
+ happens implicitly based on the *_charset* argument.
+
diff --git a/Doc/library/email.parser.rst b/Doc/library/email.parser.rst
new file mode 100644
index 0000000000..048ed2277e
--- /dev/null
+++ b/Doc/library/email.parser.rst
@@ -0,0 +1,220 @@
+:mod:`email`: Parsing email messages
+------------------------------------
+
+.. module:: email.parser
+ :synopsis: Parse flat text email messages to produce a message object structure.
+
+
+Message object structures can be created in one of two ways: they can be created
+from whole cloth by instantiating :class:`Message` objects and stringing them
+together via :meth:`attach` and :meth:`set_payload` calls, or they can be
+created by parsing a flat text representation of the email message.
+
+The :mod:`email` package provides a standard parser that understands most email
+document structures, including MIME documents. You can pass the parser a string
+or a file object, and the parser will return to you the root :class:`Message`
+instance of the object structure. For simple, non-MIME messages the payload of
+this root object will likely be a string containing the text of the message.
+For MIME messages, the root object will return ``True`` from its
+:meth:`is_multipart` method, and the subparts can be accessed via the
+:meth:`get_payload` and :meth:`walk` methods.
+
+There are actually two parser interfaces available for use, the classic
+:class:`Parser` API and the incremental :class:`FeedParser` API. The classic
+:class:`Parser` API is fine if you have the entire text of the message in memory
+as a string, or if the entire message lives in a file on the file system.
+:class:`FeedParser` is more appropriate for when you're reading the message from
+a stream which might block waiting for more input (e.g. reading an email message
+from a socket). The :class:`FeedParser` can consume and parse the message
+incrementally, and only returns the root object when you close the parser [#]_.
+
+Note that the parser can be extended in limited ways, and of course you can
+implement your own parser completely from scratch. There is no magical
+connection between the :mod:`email` package's bundled parser and the
+:class:`Message` class, so your custom parser can create message object trees
+any way it finds necessary.
+
+
+FeedParser API
+^^^^^^^^^^^^^^
+
+.. versionadded:: 2.4
+
+The :class:`FeedParser`, imported from the :mod:`email.feedparser` module,
+provides an API that is conducive to incremental parsing of email messages, such
+as would be necessary when reading the text of an email message from a source
+that can block (e.g. a socket). The :class:`FeedParser` can of course be used
+to parse an email message fully contained in a string or a file, but the classic
+:class:`Parser` API may be more convenient for such use cases. The semantics
+and results of the two parser APIs are identical.
+
+The :class:`FeedParser`'s API is simple; you create an instance, feed it a bunch
+of text until there's no more to feed it, then close the parser to retrieve the
+root message object. The :class:`FeedParser` is extremely accurate when parsing
+standards-compliant messages, and it does a very good job of parsing
+non-compliant messages, providing information about how a message was deemed
+broken. It will populate a message object's *defects* attribute with a list of
+any problems it found in a message. See the :mod:`email.errors` module for the
+list of defects that it can find.
+
+Here is the API for the :class:`FeedParser`:
+
+
+.. class:: FeedParser([_factory])
+
+ Create a :class:`FeedParser` instance. Optional *_factory* is a no-argument
+ callable that will be called whenever a new message object is needed. It
+ defaults to the :class:`email.message.Message` class.
+
+
+.. method:: FeedParser.feed(data)
+
+ Feed the :class:`FeedParser` some more data. *data* should be a string
+ containing one or more lines. The lines can be partial and the
+ :class:`FeedParser` will stitch such partial lines together properly. The lines
+ in the string can have any of the common three line endings, carriage return,
+ newline, or carriage return and newline (they can even be mixed).
+
+
+.. method:: FeedParser.close()
+
+ Closing a :class:`FeedParser` completes the parsing of all previously fed data,
+ and returns the root message object. It is undefined what happens if you feed
+ more data to a closed :class:`FeedParser`.
+
+
+Parser class API
+^^^^^^^^^^^^^^^^
+
+The :class:`Parser` class, imported from the :mod:`email.parser` module,
+provides an API that can be used to parse a message when the complete contents
+of the message are available in a string or file. The :mod:`email.parser`
+module also provides a second class, called :class:`HeaderParser` which can be
+used if you're only interested in the headers of the message.
+:class:`HeaderParser` can be much faster in these situations, since it does not
+attempt to parse the message body, instead setting the payload to the raw body
+as a string. :class:`HeaderParser` has the same API as the :class:`Parser`
+class.
+
+
+.. class:: Parser([_class])
+
+ The constructor for the :class:`Parser` class takes an optional argument
+ *_class*. This must be a callable factory (such as a function or a class), and
+ it is used whenever a sub-message object needs to be created. It defaults to
+ :class:`Message` (see :mod:`email.message`). The factory will be called without
+ arguments.
+
+ The optional *strict* flag is ignored.
+
+ .. deprecated:: 2.4
+ Because the :class:`Parser` class is a backward compatible API wrapper
+ around the new-in-Python 2.4 :class:`FeedParser`, *all* parsing is
+ effectively non-strict. You should simply stop passing a *strict* flag to
+ the :class:`Parser` constructor.
+
+ .. versionchanged:: 2.2.2
+ The *strict* flag was added.
+
+ .. versionchanged:: 2.4
+ The *strict* flag was deprecated.
+
+The other public :class:`Parser` methods are:
+
+
+.. method:: Parser.parse(fp[, headersonly])
+
+ Read all the data from the file-like object *fp*, parse the resulting text, and
+ return the root message object. *fp* must support both the :meth:`readline` and
+ the :meth:`read` methods on file-like objects.
+
+ The text contained in *fp* must be formatted as a block of :rfc:`2822` style
+ headers and header continuation lines, optionally preceded by a envelope
+ header. The header block is terminated either by the end of the data or by a
+ blank line. Following the header block is the body of the message (which may
+ contain MIME-encoded subparts).
+
+ Optional *headersonly* is as with the :meth:`parse` method.
+
+ .. versionchanged:: 2.2.2
+ The *headersonly* flag was added.
+
+
+.. method:: Parser.parsestr(text[, headersonly])
+
+ Similar to the :meth:`parse` method, except it takes a string object instead of
+ a file-like object. Calling this method on a string is exactly equivalent to
+ wrapping *text* in a :class:`StringIO` instance first and calling :meth:`parse`.
+
+ Optional *headersonly* is a flag specifying whether to stop parsing after
+ reading the headers or not. The default is ``False``, meaning it parses the
+ entire contents of the file.
+
+ .. versionchanged:: 2.2.2
+ The *headersonly* flag was added.
+
+Since creating a message object structure from a string or a file object is such
+a common task, two functions are provided as a convenience. They are available
+in the top-level :mod:`email` package namespace.
+
+
+.. function:: message_from_string(s[, _class[, strict]])
+
+ Return a message object structure from a string. This is exactly equivalent to
+ ``Parser().parsestr(s)``. Optional *_class* and *strict* are interpreted as
+ with the :class:`Parser` class constructor.
+
+ .. versionchanged:: 2.2.2
+ The *strict* flag was added.
+
+
+.. function:: message_from_file(fp[, _class[, strict]])
+
+ Return a message object structure tree from an open file object. This is
+ exactly equivalent to ``Parser().parse(fp)``. Optional *_class* and *strict*
+ are interpreted as with the :class:`Parser` class constructor.
+
+ .. versionchanged:: 2.2.2
+ The *strict* flag was added.
+
+Here's an example of how you might use this at an interactive Python prompt::
+
+ >>> import email
+ >>> msg = email.message_from_string(myString)
+
+
+Additional notes
+^^^^^^^^^^^^^^^^
+
+Here are some notes on the parsing semantics:
+
+* Most non-\ :mimetype:`multipart` type messages are parsed as a single message
+ object with a string payload. These objects will return ``False`` for
+ :meth:`is_multipart`. Their :meth:`get_payload` method will return a string
+ object.
+
+* All :mimetype:`multipart` type messages will be parsed as a container message
+ object with a list of sub-message objects for their payload. The outer
+ container message will return ``True`` for :meth:`is_multipart` and their
+ :meth:`get_payload` method will return the list of :class:`Message` subparts.
+
+* Most messages with a content type of :mimetype:`message/\*` (e.g.
+ :mimetype:`message/delivery-status` and :mimetype:`message/rfc822`) will also be
+ parsed as container object containing a list payload of length 1. Their
+ :meth:`is_multipart` method will return ``True``. The single element in the
+ list payload will be a sub-message object.
+
+* Some non-standards compliant messages may not be internally consistent about
+ their :mimetype:`multipart`\ -edness. Such messages may have a
+ :mailheader:`Content-Type` header of type :mimetype:`multipart`, but their
+ :meth:`is_multipart` method may return ``False``. If such messages were parsed
+ with the :class:`FeedParser`, they will have an instance of the
+ :class:`MultipartInvariantViolationDefect` class in their *defects* attribute
+ list. See :mod:`email.errors` for details.
+
+.. rubric:: Footnotes
+
+.. [#] As of email package version 3.0, introduced in Python 2.4, the classic
+ :class:`Parser` was re-implemented in terms of the :class:`FeedParser`, so the
+ semantics and results are identical between the two parsers.
+
diff --git a/Doc/library/email.rst b/Doc/library/email.rst
new file mode 100644
index 0000000000..212c3215d6
--- /dev/null
+++ b/Doc/library/email.rst
@@ -0,0 +1,324 @@
+.. % Copyright (C) 2001-2007 Python Software Foundation
+.. % Author: barry@python.org (Barry Warsaw)
+
+
+:mod:`email` --- An email and MIME handling package
+===================================================
+
+.. module:: email
+ :synopsis: Package supporting the parsing, manipulating, and generating email messages,
+ including MIME documents.
+.. moduleauthor:: Barry A. Warsaw <barry@python.org>
+.. sectionauthor:: Barry A. Warsaw <barry@python.org>
+
+
+.. versionadded:: 2.2
+
+The :mod:`email` package is a library for managing email messages, including
+MIME and other :rfc:`2822`\ -based message documents. It subsumes most of the
+functionality in several older standard modules such as :mod:`rfc822`,
+:mod:`mimetools`, :mod:`multifile`, and other non-standard packages such as
+:mod:`mimecntl`. It is specifically *not* designed to do any sending of email
+messages to SMTP (:rfc:`2821`), NNTP, or other servers; those are functions of
+modules such as :mod:`smtplib` and :mod:`nntplib`. The :mod:`email` package
+attempts to be as RFC-compliant as possible, supporting in addition to
+:rfc:`2822`, such MIME-related RFCs as :rfc:`2045`, :rfc:`2046`, :rfc:`2047`,
+and :rfc:`2231`.
+
+The primary distinguishing feature of the :mod:`email` package is that it splits
+the parsing and generating of email messages from the internal *object model*
+representation of email. Applications using the :mod:`email` package deal
+primarily with objects; you can add sub-objects to messages, remove sub-objects
+from messages, completely re-arrange the contents, etc. There is a separate
+parser and a separate generator which handles the transformation from flat text
+to the object model, and then back to flat text again. There are also handy
+subclasses for some common MIME object types, and a few miscellaneous utilities
+that help with such common tasks as extracting and parsing message field values,
+creating RFC-compliant dates, etc.
+
+The following sections describe the functionality of the :mod:`email` package.
+The ordering follows a progression that should be common in applications: an
+email message is read as flat text from a file or other source, the text is
+parsed to produce the object structure of the email message, this structure is
+manipulated, and finally, the object tree is rendered back into flat text.
+
+It is perfectly feasible to create the object structure out of whole cloth ---
+i.e. completely from scratch. From there, a similar progression can be taken as
+above.
+
+Also included are detailed specifications of all the classes and modules that
+the :mod:`email` package provides, the exception classes you might encounter
+while using the :mod:`email` package, some auxiliary utilities, and a few
+examples. For users of the older :mod:`mimelib` package, or previous versions
+of the :mod:`email` package, a section on differences and porting is provided.
+
+Contents of the :mod:`email` package documentation:
+
+.. toctree::
+
+ email.message.rst
+ email.parser.rst
+ email.generator.rst
+ email.mime.rst
+ email.header.rst
+ email.charset.rst
+ email.encoders.rst
+ email.errors.rst
+ email.util.rst
+ email.iterators.rst
+ email-examples.rst
+
+
+.. seealso::
+
+ Module :mod:`smtplib`
+ SMTP protocol client
+
+ Module :mod:`nntplib`
+ NNTP protocol client
+
+
+.. _email-pkg-history:
+
+Package History
+---------------
+
+This table describes the release history of the email package, corresponding to
+the version of Python that the package was released with. For purposes of this
+document, when you see a note about change or added versions, these refer to the
+Python version the change was made in, *not* the email package version. This
+table also describes the Python compatibility of each version of the package.
+
++---------------+------------------------------+-----------------------+
+| email version | distributed with | compatible with |
++===============+==============================+=======================+
+| :const:`1.x` | Python 2.2.0 to Python 2.2.1 | *no longer supported* |
++---------------+------------------------------+-----------------------+
+| :const:`2.5` | Python 2.2.2+ and Python 2.3 | Python 2.1 to 2.5 |
++---------------+------------------------------+-----------------------+
+| :const:`3.0` | Python 2.4 | Python 2.3 to 2.5 |
++---------------+------------------------------+-----------------------+
+| :const:`4.0` | Python 2.5 | Python 2.3 to 2.5 |
++---------------+------------------------------+-----------------------+
+
+Here are the major differences between :mod:`email` version 4 and version 3:
+
+* All modules have been renamed according to :pep:`8` standards. For example,
+ the version 3 module :mod:`email.Message` was renamed to :mod:`email.message` in
+ version 4.
+
+* A new subpackage :mod:`email.mime` was added and all the version 3
+ :mod:`email.MIME\*` modules were renamed and situated into the :mod:`email.mime`
+ subpackage. For example, the version 3 module :mod:`email.MIMEText` was renamed
+ to :mod:`email.mime.text`.
+
+ *Note that the version 3 names will continue to work until Python 2.6*.
+
+* The :mod:`email.mime.application` module was added, which contains the
+ :class:`MIMEApplication` class.
+
+* Methods that were deprecated in version 3 have been removed. These include
+ :meth:`Generator.__call__`, :meth:`Message.get_type`,
+ :meth:`Message.get_main_type`, :meth:`Message.get_subtype`.
+
+* Fixes have been added for :rfc:`2231` support which can change some of the
+ return types for :func:`Message.get_param` and friends. Under some
+ circumstances, values which used to return a 3-tuple now return simple strings
+ (specifically, if all extended parameter segments were unencoded, there is no
+ language and charset designation expected, so the return type is now a simple
+ string). Also, %-decoding used to be done for both encoded and unencoded
+ segments; this decoding is now done only for encoded segments.
+
+Here are the major differences between :mod:`email` version 3 and version 2:
+
+* The :class:`FeedParser` class was introduced, and the :class:`Parser` class
+ was implemented in terms of the :class:`FeedParser`. All parsing therefore is
+ non-strict, and parsing will make a best effort never to raise an exception.
+ Problems found while parsing messages are stored in the message's *defect*
+ attribute.
+
+* All aspects of the API which raised :exc:`DeprecationWarning`\ s in version 2
+ have been removed. These include the *_encoder* argument to the
+ :class:`MIMEText` constructor, the :meth:`Message.add_payload` method, the
+ :func:`Utils.dump_address_pair` function, and the functions :func:`Utils.decode`
+ and :func:`Utils.encode`.
+
+* New :exc:`DeprecationWarning`\ s have been added to:
+ :meth:`Generator.__call__`, :meth:`Message.get_type`,
+ :meth:`Message.get_main_type`, :meth:`Message.get_subtype`, and the *strict*
+ argument to the :class:`Parser` class. These are expected to be removed in
+ future versions.
+
+* Support for Pythons earlier than 2.3 has been removed.
+
+Here are the differences between :mod:`email` version 2 and version 1:
+
+* The :mod:`email.Header` and :mod:`email.Charset` modules have been added.
+
+* The pickle format for :class:`Message` instances has changed. Since this was
+ never (and still isn't) formally defined, this isn't considered a backward
+ incompatibility. However if your application pickles and unpickles
+ :class:`Message` instances, be aware that in :mod:`email` version 2,
+ :class:`Message` instances now have private variables *_charset* and
+ *_default_type*.
+
+* Several methods in the :class:`Message` class have been deprecated, or their
+ signatures changed. Also, many new methods have been added. See the
+ documentation for the :class:`Message` class for details. The changes should be
+ completely backward compatible.
+
+* The object structure has changed in the face of :mimetype:`message/rfc822`
+ content types. In :mod:`email` version 1, such a type would be represented by a
+ scalar payload, i.e. the container message's :meth:`is_multipart` returned
+ false, :meth:`get_payload` was not a list object, but a single :class:`Message`
+ instance.
+
+ This structure was inconsistent with the rest of the package, so the object
+ representation for :mimetype:`message/rfc822` content types was changed. In
+ :mod:`email` version 2, the container *does* return ``True`` from
+ :meth:`is_multipart`, and :meth:`get_payload` returns a list containing a single
+ :class:`Message` item.
+
+ Note that this is one place that backward compatibility could not be completely
+ maintained. However, if you're already testing the return type of
+ :meth:`get_payload`, you should be fine. You just need to make sure your code
+ doesn't do a :meth:`set_payload` with a :class:`Message` instance on a container
+ with a content type of :mimetype:`message/rfc822`.
+
+* The :class:`Parser` constructor's *strict* argument was added, and its
+ :meth:`parse` and :meth:`parsestr` methods grew a *headersonly* argument. The
+ *strict* flag was also added to functions :func:`email.message_from_file` and
+ :func:`email.message_from_string`.
+
+* :meth:`Generator.__call__` is deprecated; use :meth:`Generator.flatten`
+ instead. The :class:`Generator` class has also grown the :meth:`clone` method.
+
+* The :class:`DecodedGenerator` class in the :mod:`email.Generator` module was
+ added.
+
+* The intermediate base classes :class:`MIMENonMultipart` and
+ :class:`MIMEMultipart` have been added, and interposed in the class hierarchy
+ for most of the other MIME-related derived classes.
+
+* The *_encoder* argument to the :class:`MIMEText` constructor has been
+ deprecated. Encoding now happens implicitly based on the *_charset* argument.
+
+* The following functions in the :mod:`email.Utils` module have been deprecated:
+ :func:`dump_address_pairs`, :func:`decode`, and :func:`encode`. The following
+ functions have been added to the module: :func:`make_msgid`,
+ :func:`decode_rfc2231`, :func:`encode_rfc2231`, and :func:`decode_params`.
+
+* The non-public function :func:`email.Iterators._structure` was added.
+
+
+Differences from :mod:`mimelib`
+-------------------------------
+
+The :mod:`email` package was originally prototyped as a separate library called
+`mimelib <http://mimelib.sf.net/>`_. Changes have been made so that method names
+are more consistent, and some methods or modules have either been added or
+removed. The semantics of some of the methods have also changed. For the most
+part, any functionality available in :mod:`mimelib` is still available in the
+:mod:`email` package, albeit often in a different way. Backward compatibility
+between the :mod:`mimelib` package and the :mod:`email` package was not a
+priority.
+
+Here is a brief description of the differences between the :mod:`mimelib` and
+the :mod:`email` packages, along with hints on how to port your applications.
+
+Of course, the most visible difference between the two packages is that the
+package name has been changed to :mod:`email`. In addition, the top-level
+package has the following differences:
+
+* :func:`messageFromString` has been renamed to :func:`message_from_string`.
+
+* :func:`messageFromFile` has been renamed to :func:`message_from_file`.
+
+The :class:`Message` class has the following differences:
+
+* The method :meth:`asString` was renamed to :meth:`as_string`.
+
+* The method :meth:`ismultipart` was renamed to :meth:`is_multipart`.
+
+* The :meth:`get_payload` method has grown a *decode* optional argument.
+
+* The method :meth:`getall` was renamed to :meth:`get_all`.
+
+* The method :meth:`addheader` was renamed to :meth:`add_header`.
+
+* The method :meth:`gettype` was renamed to :meth:`get_type`.
+
+* The method :meth:`getmaintype` was renamed to :meth:`get_main_type`.
+
+* The method :meth:`getsubtype` was renamed to :meth:`get_subtype`.
+
+* The method :meth:`getparams` was renamed to :meth:`get_params`. Also, whereas
+ :meth:`getparams` returned a list of strings, :meth:`get_params` returns a list
+ of 2-tuples, effectively the key/value pairs of the parameters, split on the
+ ``'='`` sign.
+
+* The method :meth:`getparam` was renamed to :meth:`get_param`.
+
+* The method :meth:`getcharsets` was renamed to :meth:`get_charsets`.
+
+* The method :meth:`getfilename` was renamed to :meth:`get_filename`.
+
+* The method :meth:`getboundary` was renamed to :meth:`get_boundary`.
+
+* The method :meth:`setboundary` was renamed to :meth:`set_boundary`.
+
+* The method :meth:`getdecodedpayload` was removed. To get similar
+ functionality, pass the value 1 to the *decode* flag of the get_payload()
+ method.
+
+* The method :meth:`getpayloadastext` was removed. Similar functionality is
+ supported by the :class:`DecodedGenerator` class in the :mod:`email.generator`
+ module.
+
+* The method :meth:`getbodyastext` was removed. You can get similar
+ functionality by creating an iterator with :func:`typed_subpart_iterator` in the
+ :mod:`email.iterators` module.
+
+The :class:`Parser` class has no differences in its public interface. It does
+have some additional smarts to recognize :mimetype:`message/delivery-status`
+type messages, which it represents as a :class:`Message` instance containing
+separate :class:`Message` subparts for each header block in the delivery status
+notification [#]_.
+
+The :class:`Generator` class has no differences in its public interface. There
+is a new class in the :mod:`email.generator` module though, called
+:class:`DecodedGenerator` which provides most of the functionality previously
+available in the :meth:`Message.getpayloadastext` method.
+
+The following modules and classes have been changed:
+
+* The :class:`MIMEBase` class constructor arguments *_major* and *_minor* have
+ changed to *_maintype* and *_subtype* respectively.
+
+* The ``Image`` class/module has been renamed to ``MIMEImage``. The *_minor*
+ argument has been renamed to *_subtype*.
+
+* The ``Text`` class/module has been renamed to ``MIMEText``. The *_minor*
+ argument has been renamed to *_subtype*.
+
+* The ``MessageRFC822`` class/module has been renamed to ``MIMEMessage``. Note
+ that an earlier version of :mod:`mimelib` called this class/module ``RFC822``,
+ but that clashed with the Python standard library module :mod:`rfc822` on some
+ case-insensitive file systems.
+
+ Also, the :class:`MIMEMessage` class now represents any kind of MIME message
+ with main type :mimetype:`message`. It takes an optional argument *_subtype*
+ which is used to set the MIME subtype. *_subtype* defaults to
+ :mimetype:`rfc822`.
+
+:mod:`mimelib` provided some utility functions in its :mod:`address` and
+:mod:`date` modules. All of these functions have been moved to the
+:mod:`email.utils` module.
+
+The ``MsgReader`` class/module has been removed. Its functionality is most
+closely supported in the :func:`body_line_iterator` function in the
+:mod:`email.iterators` module.
+
+.. rubric:: Footnotes
+
+.. [#] Delivery Status Notifications (DSN) are defined in :rfc:`1894`.
diff --git a/Doc/library/email.util.rst b/Doc/library/email.util.rst
new file mode 100644
index 0000000000..aa6788549f
--- /dev/null
+++ b/Doc/library/email.util.rst
@@ -0,0 +1,166 @@
+:mod:`email`: Miscellaneous utilities
+-------------------------------------
+
+.. module:: email.utils
+ :synopsis: Miscellaneous email package utilities.
+
+
+There are several useful utilities provided in the :mod:`email.utils` module:
+
+
+.. function:: quote(str)
+
+ Return a new string with backslashes in *str* replaced by two backslashes, and
+ double quotes replaced by backslash-double quote.
+
+
+.. function:: unquote(str)
+
+ Return a new string which is an *unquoted* version of *str*. If *str* ends and
+ begins with double quotes, they are stripped off. Likewise if *str* ends and
+ begins with angle brackets, they are stripped off.
+
+
+.. function:: parseaddr(address)
+
+ Parse address -- which should be the value of some address-containing field such
+ as :mailheader:`To` or :mailheader:`Cc` -- into its constituent *realname* and
+ *email address* parts. Returns a tuple of that information, unless the parse
+ fails, in which case a 2-tuple of ``('', '')`` is returned.
+
+
+.. function:: formataddr(pair)
+
+ The inverse of :meth:`parseaddr`, this takes a 2-tuple of the form ``(realname,
+ email_address)`` and returns the string value suitable for a :mailheader:`To` or
+ :mailheader:`Cc` header. If the first element of *pair* is false, then the
+ second element is returned unmodified.
+
+
+.. function:: getaddresses(fieldvalues)
+
+ This method returns a list of 2-tuples of the form returned by ``parseaddr()``.
+ *fieldvalues* is a sequence of header field values as might be returned by
+ :meth:`Message.get_all`. Here's a simple example that gets all the recipients
+ of a message::
+
+ from email.utils import getaddresses
+
+ tos = msg.get_all('to', [])
+ ccs = msg.get_all('cc', [])
+ resent_tos = msg.get_all('resent-to', [])
+ resent_ccs = msg.get_all('resent-cc', [])
+ all_recipients = getaddresses(tos + ccs + resent_tos + resent_ccs)
+
+
+.. function:: parsedate(date)
+
+ Attempts to parse a date according to the rules in :rfc:`2822`. however, some
+ mailers don't follow that format as specified, so :func:`parsedate` tries to
+ guess correctly in such cases. *date* is a string containing an :rfc:`2822`
+ date, such as ``"Mon, 20 Nov 1995 19:12:08 -0500"``. If it succeeds in parsing
+ the date, :func:`parsedate` returns a 9-tuple that can be passed directly to
+ :func:`time.mktime`; otherwise ``None`` will be returned. Note that indexes 6,
+ 7, and 8 of the result tuple are not usable.
+
+
+.. function:: parsedate_tz(date)
+
+ Performs the same function as :func:`parsedate`, but returns either ``None`` or
+ a 10-tuple; the first 9 elements make up a tuple that can be passed directly to
+ :func:`time.mktime`, and the tenth is the offset of the date's timezone from UTC
+ (which is the official term for Greenwich Mean Time) [#]_. If the input string
+ has no timezone, the last element of the tuple returned is ``None``. Note that
+ indexes 6, 7, and 8 of the result tuple are not usable.
+
+
+.. function:: mktime_tz(tuple)
+
+ Turn a 10-tuple as returned by :func:`parsedate_tz` into a UTC timestamp. It
+ the timezone item in the tuple is ``None``, assume local time. Minor
+ deficiency: :func:`mktime_tz` interprets the first 8 elements of *tuple* as a
+ local time and then compensates for the timezone difference. This may yield a
+ slight error around changes in daylight savings time, though not worth worrying
+ about for common use.
+
+
+.. function:: formatdate([timeval[, localtime][, usegmt]])
+
+ Returns a date string as per :rfc:`2822`, e.g.::
+
+ Fri, 09 Nov 2001 01:08:47 -0000
+
+ Optional *timeval* if given is a floating point time value as accepted by
+ :func:`time.gmtime` and :func:`time.localtime`, otherwise the current time is
+ used.
+
+ Optional *localtime* is a flag that when ``True``, interprets *timeval*, and
+ returns a date relative to the local timezone instead of UTC, properly taking
+ daylight savings time into account. The default is ``False`` meaning UTC is
+ used.
+
+ Optional *usegmt* is a flag that when ``True``, outputs a date string with the
+ timezone as an ascii string ``GMT``, rather than a numeric ``-0000``. This is
+ needed for some protocols (such as HTTP). This only applies when *localtime* is
+ ``False``.
+
+ .. versionadded:: 2.4
+
+
+.. function:: make_msgid([idstring])
+
+ Returns a string suitable for an :rfc:`2822`\ -compliant
+ :mailheader:`Message-ID` header. Optional *idstring* if given, is a string used
+ to strengthen the uniqueness of the message id.
+
+
+.. function:: decode_rfc2231(s)
+
+ Decode the string *s* according to :rfc:`2231`.
+
+
+.. function:: encode_rfc2231(s[, charset[, language]])
+
+ Encode the string *s* according to :rfc:`2231`. Optional *charset* and
+ *language*, if given is the character set name and language name to use. If
+ neither is given, *s* is returned as-is. If *charset* is given but *language*
+ is not, the string is encoded using the empty string for *language*.
+
+
+.. function:: collapse_rfc2231_value(value[, errors[, fallback_charset]])
+
+ When a header parameter is encoded in :rfc:`2231` format,
+ :meth:`Message.get_param` may return a 3-tuple containing the character set,
+ language, and value. :func:`collapse_rfc2231_value` turns this into a unicode
+ string. Optional *errors* is passed to the *errors* argument of the built-in
+ :func:`unicode` function; it defaults to ``replace``. Optional
+ *fallback_charset* specifies the character set to use if the one in the
+ :rfc:`2231` header is not known by Python; it defaults to ``us-ascii``.
+
+ For convenience, if the *value* passed to :func:`collapse_rfc2231_value` is not
+ a tuple, it should be a string and it is returned unquoted.
+
+
+.. function:: decode_params(params)
+
+ Decode parameters list according to :rfc:`2231`. *params* is a sequence of
+ 2-tuples containing elements of the form ``(content-type, string-value)``.
+
+.. versionchanged:: 2.4
+ The :func:`dump_address_pair` function has been removed; use :func:`formataddr`
+ instead.
+
+.. versionchanged:: 2.4
+ The :func:`decode` function has been removed; use the
+ :meth:`Header.decode_header` method instead.
+
+.. versionchanged:: 2.4
+ The :func:`encode` function has been removed; use the :meth:`Header.encode`
+ method instead.
+
+.. rubric:: Footnotes
+
+.. [#] Note that the sign of the timezone offset is the opposite of the sign of the
+ ``time.timezone`` variable for the same timezone; the latter variable follows
+ the POSIX standard while this module follows :rfc:`2822`.
+
diff --git a/Doc/library/errno.rst b/Doc/library/errno.rst
new file mode 100644
index 0000000000..daf9ff02d5
--- /dev/null
+++ b/Doc/library/errno.rst
@@ -0,0 +1,636 @@
+
+:mod:`errno` --- Standard errno system symbols
+==============================================
+
+.. module:: errno
+ :synopsis: Standard errno system symbols.
+
+
+This module makes available standard ``errno`` system symbols. The value of each
+symbol is the corresponding integer value. The names and descriptions are
+borrowed from :file:`linux/include/errno.h`, which should be pretty
+all-inclusive.
+
+
+.. data:: errorcode
+
+ Dictionary providing a mapping from the errno value to the string name in the
+ underlying system. For instance, ``errno.errorcode[errno.EPERM]`` maps to
+ ``'EPERM'``.
+
+To translate a numeric error code to an error message, use :func:`os.strerror`.
+
+Of the following list, symbols that are not used on the current platform are not
+defined by the module. The specific list of defined symbols is available as
+``errno.errorcode.keys()``. Symbols available can include:
+
+
+.. data:: EPERM
+
+ Operation not permitted
+
+
+.. data:: ENOENT
+
+ No such file or directory
+
+
+.. data:: ESRCH
+
+ No such process
+
+
+.. data:: EINTR
+
+ Interrupted system call
+
+
+.. data:: EIO
+
+ I/O error
+
+
+.. data:: ENXIO
+
+ No such device or address
+
+
+.. data:: E2BIG
+
+ Arg list too long
+
+
+.. data:: ENOEXEC
+
+ Exec format error
+
+
+.. data:: EBADF
+
+ Bad file number
+
+
+.. data:: ECHILD
+
+ No child processes
+
+
+.. data:: EAGAIN
+
+ Try again
+
+
+.. data:: ENOMEM
+
+ Out of memory
+
+
+.. data:: EACCES
+
+ Permission denied
+
+
+.. data:: EFAULT
+
+ Bad address
+
+
+.. data:: ENOTBLK
+
+ Block device required
+
+
+.. data:: EBUSY
+
+ Device or resource busy
+
+
+.. data:: EEXIST
+
+ File exists
+
+
+.. data:: EXDEV
+
+ Cross-device link
+
+
+.. data:: ENODEV
+
+ No such device
+
+
+.. data:: ENOTDIR
+
+ Not a directory
+
+
+.. data:: EISDIR
+
+ Is a directory
+
+
+.. data:: EINVAL
+
+ Invalid argument
+
+
+.. data:: ENFILE
+
+ File table overflow
+
+
+.. data:: EMFILE
+
+ Too many open files
+
+
+.. data:: ENOTTY
+
+ Not a typewriter
+
+
+.. data:: ETXTBSY
+
+ Text file busy
+
+
+.. data:: EFBIG
+
+ File too large
+
+
+.. data:: ENOSPC
+
+ No space left on device
+
+
+.. data:: ESPIPE
+
+ Illegal seek
+
+
+.. data:: EROFS
+
+ Read-only file system
+
+
+.. data:: EMLINK
+
+ Too many links
+
+
+.. data:: EPIPE
+
+ Broken pipe
+
+
+.. data:: EDOM
+
+ Math argument out of domain of func
+
+
+.. data:: ERANGE
+
+ Math result not representable
+
+
+.. data:: EDEADLK
+
+ Resource deadlock would occur
+
+
+.. data:: ENAMETOOLONG
+
+ File name too long
+
+
+.. data:: ENOLCK
+
+ No record locks available
+
+
+.. data:: ENOSYS
+
+ Function not implemented
+
+
+.. data:: ENOTEMPTY
+
+ Directory not empty
+
+
+.. data:: ELOOP
+
+ Too many symbolic links encountered
+
+
+.. data:: EWOULDBLOCK
+
+ Operation would block
+
+
+.. data:: ENOMSG
+
+ No message of desired type
+
+
+.. data:: EIDRM
+
+ Identifier removed
+
+
+.. data:: ECHRNG
+
+ Channel number out of range
+
+
+.. data:: EL2NSYNC
+
+ Level 2 not synchronized
+
+
+.. data:: EL3HLT
+
+ Level 3 halted
+
+
+.. data:: EL3RST
+
+ Level 3 reset
+
+
+.. data:: ELNRNG
+
+ Link number out of range
+
+
+.. data:: EUNATCH
+
+ Protocol driver not attached
+
+
+.. data:: ENOCSI
+
+ No CSI structure available
+
+
+.. data:: EL2HLT
+
+ Level 2 halted
+
+
+.. data:: EBADE
+
+ Invalid exchange
+
+
+.. data:: EBADR
+
+ Invalid request descriptor
+
+
+.. data:: EXFULL
+
+ Exchange full
+
+
+.. data:: ENOANO
+
+ No anode
+
+
+.. data:: EBADRQC
+
+ Invalid request code
+
+
+.. data:: EBADSLT
+
+ Invalid slot
+
+
+.. data:: EDEADLOCK
+
+ File locking deadlock error
+
+
+.. data:: EBFONT
+
+ Bad font file format
+
+
+.. data:: ENOSTR
+
+ Device not a stream
+
+
+.. data:: ENODATA
+
+ No data available
+
+
+.. data:: ETIME
+
+ Timer expired
+
+
+.. data:: ENOSR
+
+ Out of streams resources
+
+
+.. data:: ENONET
+
+ Machine is not on the network
+
+
+.. data:: ENOPKG
+
+ Package not installed
+
+
+.. data:: EREMOTE
+
+ Object is remote
+
+
+.. data:: ENOLINK
+
+ Link has been severed
+
+
+.. data:: EADV
+
+ Advertise error
+
+
+.. data:: ESRMNT
+
+ Srmount error
+
+
+.. data:: ECOMM
+
+ Communication error on send
+
+
+.. data:: EPROTO
+
+ Protocol error
+
+
+.. data:: EMULTIHOP
+
+ Multihop attempted
+
+
+.. data:: EDOTDOT
+
+ RFS specific error
+
+
+.. data:: EBADMSG
+
+ Not a data message
+
+
+.. data:: EOVERFLOW
+
+ Value too large for defined data type
+
+
+.. data:: ENOTUNIQ
+
+ Name not unique on network
+
+
+.. data:: EBADFD
+
+ File descriptor in bad state
+
+
+.. data:: EREMCHG
+
+ Remote address changed
+
+
+.. data:: ELIBACC
+
+ Can not access a needed shared library
+
+
+.. data:: ELIBBAD
+
+ Accessing a corrupted shared library
+
+
+.. data:: ELIBSCN
+
+ .lib section in a.out corrupted
+
+
+.. data:: ELIBMAX
+
+ Attempting to link in too many shared libraries
+
+
+.. data:: ELIBEXEC
+
+ Cannot exec a shared library directly
+
+
+.. data:: EILSEQ
+
+ Illegal byte sequence
+
+
+.. data:: ERESTART
+
+ Interrupted system call should be restarted
+
+
+.. data:: ESTRPIPE
+
+ Streams pipe error
+
+
+.. data:: EUSERS
+
+ Too many users
+
+
+.. data:: ENOTSOCK
+
+ Socket operation on non-socket
+
+
+.. data:: EDESTADDRREQ
+
+ Destination address required
+
+
+.. data:: EMSGSIZE
+
+ Message too long
+
+
+.. data:: EPROTOTYPE
+
+ Protocol wrong type for socket
+
+
+.. data:: ENOPROTOOPT
+
+ Protocol not available
+
+
+.. data:: EPROTONOSUPPORT
+
+ Protocol not supported
+
+
+.. data:: ESOCKTNOSUPPORT
+
+ Socket type not supported
+
+
+.. data:: EOPNOTSUPP
+
+ Operation not supported on transport endpoint
+
+
+.. data:: EPFNOSUPPORT
+
+ Protocol family not supported
+
+
+.. data:: EAFNOSUPPORT
+
+ Address family not supported by protocol
+
+
+.. data:: EADDRINUSE
+
+ Address already in use
+
+
+.. data:: EADDRNOTAVAIL
+
+ Cannot assign requested address
+
+
+.. data:: ENETDOWN
+
+ Network is down
+
+
+.. data:: ENETUNREACH
+
+ Network is unreachable
+
+
+.. data:: ENETRESET
+
+ Network dropped connection because of reset
+
+
+.. data:: ECONNABORTED
+
+ Software caused connection abort
+
+
+.. data:: ECONNRESET
+
+ Connection reset by peer
+
+
+.. data:: ENOBUFS
+
+ No buffer space available
+
+
+.. data:: EISCONN
+
+ Transport endpoint is already connected
+
+
+.. data:: ENOTCONN
+
+ Transport endpoint is not connected
+
+
+.. data:: ESHUTDOWN
+
+ Cannot send after transport endpoint shutdown
+
+
+.. data:: ETOOMANYREFS
+
+ Too many references: cannot splice
+
+
+.. data:: ETIMEDOUT
+
+ Connection timed out
+
+
+.. data:: ECONNREFUSED
+
+ Connection refused
+
+
+.. data:: EHOSTDOWN
+
+ Host is down
+
+
+.. data:: EHOSTUNREACH
+
+ No route to host
+
+
+.. data:: EALREADY
+
+ Operation already in progress
+
+
+.. data:: EINPROGRESS
+
+ Operation now in progress
+
+
+.. data:: ESTALE
+
+ Stale NFS file handle
+
+
+.. data:: EUCLEAN
+
+ Structure needs cleaning
+
+
+.. data:: ENOTNAM
+
+ Not a XENIX named type file
+
+
+.. data:: ENAVAIL
+
+ No XENIX semaphores available
+
+
+.. data:: EISNAM
+
+ Is a named type file
+
+
+.. data:: EREMOTEIO
+
+ Remote I/O error
+
+
+.. data:: EDQUOT
+
+ Quota exceeded
+
diff --git a/Doc/library/exceptions.rst b/Doc/library/exceptions.rst
new file mode 100644
index 0000000000..d6a64fc1b9
--- /dev/null
+++ b/Doc/library/exceptions.rst
@@ -0,0 +1,475 @@
+.. _bltin-exceptions:
+
+Built-in Exceptions
+===================
+
+.. module:: exceptions
+ :synopsis: Standard exception classes.
+
+
+Exceptions should be class objects. The exceptions are defined in the module
+:mod:`exceptions`. This module never needs to be imported explicitly: the
+exceptions are provided in the built-in namespace as well as the
+:mod:`exceptions` module.
+
+.. index::
+ statement: try
+ statement: except
+
+For class exceptions, in a :keyword:`try` statement with an :keyword:`except`
+clause that mentions a particular class, that clause also handles any exception
+classes derived from that class (but not exception classes from which *it* is
+derived). Two exception classes that are not related via subclassing are never
+equivalent, even if they have the same name.
+
+.. index:: statement: raise
+
+The built-in exceptions listed below can be generated by the interpreter or
+built-in functions. Except where mentioned, they have an "associated value"
+indicating the detailed cause of the error. This may be a string or a tuple
+containing several items of information (e.g., an error code and a string
+explaining the code). The associated value is the second argument to the
+:keyword:`raise` statement. If the exception class is derived from the standard
+root class :exc:`BaseException`, the associated value is present as the
+exception instance's :attr:`args` attribute.
+
+User code can raise built-in exceptions. This can be used to test an exception
+handler or to report an error condition "just like" the situation in which the
+interpreter raises the same exception; but beware that there is nothing to
+prevent user code from raising an inappropriate error.
+
+The built-in exception classes can be sub-classed to define new exceptions;
+programmers are encouraged to at least derive new exceptions from the
+:exc:`Exception` class and not :exc:`BaseException`. More information on
+defining exceptions is available in the Python Tutorial under
+:ref:`tut-userexceptions`.
+
+The following exceptions are only used as base classes for other exceptions.
+
+
+.. exception:: BaseException
+
+ The base class for all built-in exceptions. It is not meant to be directly
+ inherited by user-defined classes (for that use :exc:`Exception`). If
+ :func:`str` or :func:`unicode` is called on an instance of this class, the
+ representation of the argument(s) to the instance are returned or the emptry
+ string when there were no arguments. All arguments are stored in :attr:`args`
+ as a tuple.
+
+ .. versionadded:: 2.5
+
+
+.. exception:: Exception
+
+ All built-in, non-system-exiting exceptions are derived from this class. All
+ user-defined exceptions should also be derived from this class.
+
+ .. versionchanged:: 2.5
+ Changed to inherit from :exc:`BaseException`.
+
+
+.. exception:: ArithmeticError
+
+ The base class for those built-in exceptions that are raised for various
+ arithmetic errors: :exc:`OverflowError`, :exc:`ZeroDivisionError`,
+ :exc:`FloatingPointError`.
+
+
+.. exception:: LookupError
+
+ The base class for the exceptions that are raised when a key or index used on a
+ mapping or sequence is invalid: :exc:`IndexError`, :exc:`KeyError`. This can be
+ raised directly by :func:`sys.setdefaultencoding`.
+
+
+.. exception:: EnvironmentError
+
+ The base class for exceptions that can occur outside the Python system:
+ :exc:`IOError`, :exc:`OSError`. When exceptions of this type are created with a
+ 2-tuple, the first item is available on the instance's :attr:`errno` attribute
+ (it is assumed to be an error number), and the second item is available on the
+ :attr:`strerror` attribute (it is usually the associated error message). The
+ tuple itself is also available on the :attr:`args` attribute.
+
+ .. versionadded:: 1.5.2
+
+ When an :exc:`EnvironmentError` exception is instantiated with a 3-tuple, the
+ first two items are available as above, while the third item is available on the
+ :attr:`filename` attribute. However, for backwards compatibility, the
+ :attr:`args` attribute contains only a 2-tuple of the first two constructor
+ arguments.
+
+ The :attr:`filename` attribute is ``None`` when this exception is created with
+ other than 3 arguments. The :attr:`errno` and :attr:`strerror` attributes are
+ also ``None`` when the instance was created with other than 2 or 3 arguments.
+ In this last case, :attr:`args` contains the verbatim constructor arguments as a
+ tuple.
+
+The following exceptions are the exceptions that are actually raised.
+
+
+.. exception:: AssertionError
+
+ .. index:: statement: assert
+
+ Raised when an :keyword:`assert` statement fails.
+
+
+.. exception:: AttributeError
+
+ Raised when an attribute reference or assignment fails. (When an object does
+ not support attribute references or attribute assignments at all,
+ :exc:`TypeError` is raised.)
+
+ .. % xref to attribute reference?
+
+
+.. exception:: EOFError
+
+ Raised when attempting to read beyond the end of a file. (N.B.: the :meth:`read`
+ and :meth:`readline` methods of file objects return an empty string when they
+ hit EOF.)
+
+ .. % XXXJH xrefs here
+ .. % XXXJH xrefs here
+
+
+.. exception:: FloatingPointError
+
+ Raised when a floating point operation fails. This exception is always defined,
+ but can only be raised when Python is configured with the
+ :option:`--with-fpectl` option, or the :const:`WANT_SIGFPE_HANDLER` symbol is
+ defined in the :file:`pyconfig.h` file.
+
+
+.. exception:: GeneratorExit
+
+ Raise when a generator's :meth:`close` method is called.
+
+ .. versionadded:: 2.5
+
+ .. versionchanged:: 3.0
+ Changed to inherit from Exception instead of StandardError.
+
+
+.. exception:: IOError
+
+ Raised when an I/O operation (such as a :keyword:`print` statement, the built-in
+ :func:`open` function or a method of a file object) fails for an I/O-related
+ reason, e.g., "file not found" or "disk full".
+
+ .. % XXXJH xrefs here
+
+ This class is derived from :exc:`EnvironmentError`. See the discussion above
+ for more information on exception instance attributes.
+
+
+.. exception:: ImportError
+
+ Raised when an :keyword:`import` statement fails to find the module definition
+ or when a ``from ... import`` fails to find a name that is to be imported.
+
+ .. % XXXJH xref to import statement?
+
+
+.. exception:: IndexError
+
+ Raised when a sequence subscript is out of range. (Slice indices are silently
+ truncated to fall in the allowed range; if an index is not a plain integer,
+ :exc:`TypeError` is raised.)
+
+ .. % XXXJH xref to sequences
+
+
+.. exception:: KeyError
+
+ Raised when a mapping (dictionary) key is not found in the set of existing keys.
+
+ .. % XXXJH xref to mapping objects?
+
+
+.. exception:: KeyboardInterrupt
+
+ Raised when the user hits the interrupt key (normally :kbd:`Control-C` or
+ :kbd:`Delete`). During execution, a check for interrupts is made regularly. The
+ exception inherits from :exc:`BaseException` so as to not be accidentally caught
+ by code that catches :exc:`Exception` and thus prevent the interpreter from
+ exiting.
+
+ .. % XXX(hylton) xrefs here
+
+ .. versionchanged:: 2.5
+ Changed to inherit from :exc:`BaseException`.
+
+
+.. exception:: MemoryError
+
+ Raised when an operation runs out of memory but the situation may still be
+ rescued (by deleting some objects). The associated value is a string indicating
+ what kind of (internal) operation ran out of memory. Note that because of the
+ underlying memory management architecture (C's :cfunc:`malloc` function), the
+ interpreter may not always be able to completely recover from this situation; it
+ nevertheless raises an exception so that a stack traceback can be printed, in
+ case a run-away program was the cause.
+
+
+.. exception:: NameError
+
+ Raised when a local or global name is not found. This applies only to
+ unqualified names. The associated value is an error message that includes the
+ name that could not be found.
+
+
+.. exception:: NotImplementedError
+
+ This exception is derived from :exc:`RuntimeError`. In user defined base
+ classes, abstract methods should raise this exception when they require derived
+ classes to override the method.
+
+ .. versionadded:: 1.5.2
+
+
+.. exception:: OSError
+
+ This class is derived from :exc:`EnvironmentError` and is used primarily as the
+ :mod:`os` module's ``os.error`` exception. See :exc:`EnvironmentError` above for
+ a description of the possible associated values.
+
+ .. % xref for os module
+
+ .. versionadded:: 1.5.2
+
+
+.. exception:: OverflowError
+
+ Raised when the result of an arithmetic operation is too large to be
+ represented. This cannot occur for long integers (which would rather raise
+ :exc:`MemoryError` than give up). Because of the lack of standardization of
+ floating point exception handling in C, most floating point operations also
+ aren't checked. For plain integers, all operations that can overflow are
+ checked except left shift, where typical applications prefer to drop bits than
+ raise an exception.
+
+ .. % XXXJH reference to long's and/or int's?
+
+
+.. exception:: ReferenceError
+
+ This exception is raised when a weak reference proxy, created by the
+ :func:`weakref.proxy` function, is used to access an attribute of the referent
+ after it has been garbage collected. For more information on weak references,
+ see the :mod:`weakref` module.
+
+ .. versionadded:: 2.2
+ Previously known as the :exc:`weakref.ReferenceError` exception.
+
+
+.. exception:: RuntimeError
+
+ Raised when an error is detected that doesn't fall in any of the other
+ categories. The associated value is a string indicating what precisely went
+ wrong. (This exception is mostly a relic from a previous version of the
+ interpreter; it is not used very much any more.)
+
+
+.. exception:: StopIteration
+
+ Raised by builtin :func:`next` and an iterator's :meth:`__next__` method to
+ signal that there are no further values.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 3.0
+ Changed to inherit from Exception instead of StandardError.
+
+
+.. exception:: SyntaxError
+
+ Raised when the parser encounters a syntax error. This may occur in an
+ :keyword:`import` statement, in a call to the built-in functions :func:`exec`
+ or :func:`eval`, or when reading the initial script or standard input
+ (also interactively).
+
+ .. % XXXJH xref to these functions?
+
+ Instances of this class have attributes :attr:`filename`, :attr:`lineno`,
+ :attr:`offset` and :attr:`text` for easier access to the details. :func:`str`
+ of the exception instance returns only the message.
+
+
+.. exception:: SystemError
+
+ Raised when the interpreter finds an internal error, but the situation does not
+ look so serious to cause it to abandon all hope. The associated value is a
+ string indicating what went wrong (in low-level terms).
+
+ You should report this to the author or maintainer of your Python interpreter.
+ Be sure to report the version of the Python interpreter (``sys.version``; it is
+ also printed at the start of an interactive Python session), the exact error
+ message (the exception's associated value) and if possible the source of the
+ program that triggered the error.
+
+
+.. exception:: SystemExit
+
+ This exception is raised by the :func:`sys.exit` function. When it is not
+ handled, the Python interpreter exits; no stack traceback is printed. If the
+ associated value is a plain integer, it specifies the system exit status (passed
+ to C's :cfunc:`exit` function); if it is ``None``, the exit status is zero; if
+ it has another type (such as a string), the object's value is printed and the
+ exit status is one.
+
+ .. % XXX(hylton) xref to module sys?
+
+ Instances have an attribute :attr:`code` which is set to the proposed exit
+ status or error message (defaulting to ``None``). Also, this exception derives
+ directly from :exc:`BaseException` and not :exc:`Exception`, since it is not
+ technically an error.
+
+ A call to :func:`sys.exit` is translated into an exception so that clean-up
+ handlers (:keyword:`finally` clauses of :keyword:`try` statements) can be
+ executed, and so that a debugger can execute a script without running the risk
+ of losing control. The :func:`os._exit` function can be used if it is
+ absolutely positively necessary to exit immediately (for example, in the child
+ process after a call to :func:`fork`).
+
+ The exception inherits from :exc:`BaseException` instead of :exc:`Exception` so
+ that it is not accidentally caught by code that catches :exc:`Exception`. This
+ allows the exception to properly propagate up and cause the interpreter to exit.
+
+ .. versionchanged:: 2.5
+ Changed to inherit from :exc:`BaseException`.
+
+
+.. exception:: TypeError
+
+ Raised when an operation or function is applied to an object of inappropriate
+ type. The associated value is a string giving details about the type mismatch.
+
+
+.. exception:: UnboundLocalError
+
+ Raised when a reference is made to a local variable in a function or method, but
+ no value has been bound to that variable. This is a subclass of
+ :exc:`NameError`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: UnicodeError
+
+ Raised when a Unicode-related encoding or decoding error occurs. It is a
+ subclass of :exc:`ValueError`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: UnicodeEncodeError
+
+ Raised when a Unicode-related error occurs during encoding. It is a subclass of
+ :exc:`UnicodeError`.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: UnicodeDecodeError
+
+ Raised when a Unicode-related error occurs during decoding. It is a subclass of
+ :exc:`UnicodeError`.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: UnicodeTranslateError
+
+ Raised when a Unicode-related error occurs during translating. It is a subclass
+ of :exc:`UnicodeError`.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: ValueError
+
+ Raised when a built-in operation or function receives an argument that has the
+ right type but an inappropriate value, and the situation is not described by a
+ more precise exception such as :exc:`IndexError`.
+
+
+.. exception:: WindowsError
+
+ Raised when a Windows-specific error occurs or when the error number does not
+ correspond to an :cdata:`errno` value. The :attr:`winerror` and
+ :attr:`strerror` values are created from the return values of the
+ :cfunc:`GetLastError` and :cfunc:`FormatMessage` functions from the Windows
+ Platform API. The :attr:`errno` value maps the :attr:`winerror` value to
+ corresponding ``errno.h`` values. This is a subclass of :exc:`OSError`.
+
+ .. versionadded:: 2.0
+
+ .. versionchanged:: 2.5
+ Previous versions put the :cfunc:`GetLastError` codes into :attr:`errno`.
+
+
+.. exception:: ZeroDivisionError
+
+ Raised when the second argument of a division or modulo operation is zero. The
+ associated value is a string indicating the type of the operands and the
+ operation.
+
+The following exceptions are used as warning categories; see the :mod:`warnings`
+module for more information.
+
+
+.. exception:: Warning
+
+ Base class for warning categories.
+
+
+.. exception:: UserWarning
+
+ Base class for warnings generated by user code.
+
+
+.. exception:: DeprecationWarning
+
+ Base class for warnings about deprecated features.
+
+
+.. exception:: PendingDeprecationWarning
+
+ Base class for warnings about features which will be deprecated in the future.
+
+
+.. exception:: SyntaxWarning
+
+ Base class for warnings about dubious syntax
+
+
+.. exception:: RuntimeWarning
+
+ Base class for warnings about dubious runtime behavior.
+
+
+.. exception:: FutureWarning
+
+ Base class for warnings about constructs that will change semantically in the
+ future.
+
+
+.. exception:: ImportWarning
+
+ Base class for warnings about probable mistakes in module imports.
+
+ .. versionadded:: 2.5
+
+
+.. exception:: UnicodeWarning
+
+ Base class for warnings related to Unicode.
+
+ .. versionadded:: 2.5
+
+The class hierarchy for built-in exceptions is:
+
+
+.. literalinclude:: ../../Lib/test/exception_hierarchy.txt
diff --git a/Doc/library/fcntl.rst b/Doc/library/fcntl.rst
new file mode 100644
index 0000000000..2d7bb9cbb2
--- /dev/null
+++ b/Doc/library/fcntl.rst
@@ -0,0 +1,155 @@
+
+:mod:`fcntl` --- The :func:`fcntl` and :func:`ioctl` system calls
+=================================================================
+
+.. module:: fcntl
+ :platform: Unix
+ :synopsis: The fcntl() and ioctl() system calls.
+.. sectionauthor:: Jaap Vermeulen
+
+
+.. index::
+ pair: UNIX@Unix; file control
+ pair: UNIX@Unix; I/O control
+
+This module performs file control and I/O control on file descriptors. It is an
+interface to the :cfunc:`fcntl` and :cfunc:`ioctl` Unix routines.
+
+All functions in this module take a file descriptor *fd* as their first
+argument. This can be an integer file descriptor, such as returned by
+``sys.stdin.fileno()``, or a file object, such as ``sys.stdin`` itself, which
+provides a :meth:`fileno` which returns a genuine file descriptor.
+
+The module defines the following functions:
+
+
+.. function:: fcntl(fd, op[, arg])
+
+ Perform the requested operation on file descriptor *fd* (file objects providing
+ a :meth:`fileno` method are accepted as well). The operation is defined by *op*
+ and is operating system dependent. These codes are also found in the
+ :mod:`fcntl` module. The argument *arg* is optional, and defaults to the integer
+ value ``0``. When present, it can either be an integer value, or a string.
+ With the argument missing or an integer value, the return value of this function
+ is the integer return value of the C :cfunc:`fcntl` call. When the argument is
+ a string it represents a binary structure, e.g. created by :func:`struct.pack`.
+ The binary data is copied to a buffer whose address is passed to the C
+ :cfunc:`fcntl` call. The return value after a successful call is the contents
+ of the buffer, converted to a string object. The length of the returned string
+ will be the same as the length of the *arg* argument. This is limited to 1024
+ bytes. If the information returned in the buffer by the operating system is
+ larger than 1024 bytes, this is most likely to result in a segmentation
+ violation or a more subtle data corruption.
+
+ If the :cfunc:`fcntl` fails, an :exc:`IOError` is raised.
+
+
+.. function:: ioctl(fd, op[, arg[, mutate_flag]])
+
+ This function is identical to the :func:`fcntl` function, except that the
+ operations are typically defined in the library module :mod:`termios` and the
+ argument handling is even more complicated.
+
+ The parameter *arg* can be one of an integer, absent (treated identically to the
+ integer ``0``), an object supporting the read-only buffer interface (most likely
+ a plain Python string) or an object supporting the read-write buffer interface.
+
+ In all but the last case, behaviour is as for the :func:`fcntl` function.
+
+ If a mutable buffer is passed, then the behaviour is determined by the value of
+ the *mutate_flag* parameter.
+
+ If it is false, the buffer's mutability is ignored and behaviour is as for a
+ read-only buffer, except that the 1024 byte limit mentioned above is avoided --
+ so long as the buffer you pass is as least as long as what the operating system
+ wants to put there, things should work.
+
+ If *mutate_flag* is true, then the buffer is (in effect) passed to the
+ underlying :func:`ioctl` system call, the latter's return code is passed back to
+ the calling Python, and the buffer's new contents reflect the action of the
+ :func:`ioctl`. This is a slight simplification, because if the supplied buffer
+ is less than 1024 bytes long it is first copied into a static buffer 1024 bytes
+ long which is then passed to :func:`ioctl` and copied back into the supplied
+ buffer.
+
+ If *mutate_flag* is not supplied, then from Python 2.5 it defaults to true,
+ which is a change from versions 2.3 and 2.4. Supply the argument explicitly if
+ version portability is a priority.
+
+ An example::
+
+ >>> import array, fcntl, struct, termios, os
+ >>> os.getpgrp()
+ 13341
+ >>> struct.unpack('h', fcntl.ioctl(0, termios.TIOCGPGRP, " "))[0]
+ 13341
+ >>> buf = array.array('h', [0])
+ >>> fcntl.ioctl(0, termios.TIOCGPGRP, buf, 1)
+ 0
+ >>> buf
+ array('h', [13341])
+
+
+.. function:: flock(fd, op)
+
+ Perform the lock operation *op* on file descriptor *fd* (file objects providing
+ a :meth:`fileno` method are accepted as well). See the Unix manual
+ :manpage:`flock(3)` for details. (On some systems, this function is emulated
+ using :cfunc:`fcntl`.)
+
+
+.. function:: lockf(fd, operation, [length, [start, [whence]]])
+
+ This is essentially a wrapper around the :func:`fcntl` locking calls. *fd* is
+ the file descriptor of the file to lock or unlock, and *operation* is one of the
+ following values:
+
+ * :const:`LOCK_UN` -- unlock
+ * :const:`LOCK_SH` -- acquire a shared lock
+ * :const:`LOCK_EX` -- acquire an exclusive lock
+
+ When *operation* is :const:`LOCK_SH` or :const:`LOCK_EX`, it can also be
+ bit-wise OR'd with :const:`LOCK_NB` to avoid blocking on lock acquisition.
+ If :const:`LOCK_NB` is used and the lock cannot be acquired, an
+ :exc:`IOError` will be raised and the exception will have an *errno*
+ attribute set to :const:`EACCES` or :const:`EAGAIN` (depending on the
+ operating system; for portability, check for both values). On at least some
+ systems, :const:`LOCK_EX` can only be used if the file descriptor refers to a
+ file opened for writing.
+
+ *length* is the number of bytes to lock, *start* is the byte offset at which the
+ lock starts, relative to *whence*, and *whence* is as with :func:`fileobj.seek`,
+ specifically:
+
+ * :const:`0` -- relative to the start of the file (:const:`SEEK_SET`)
+ * :const:`1` -- relative to the current buffer position (:const:`SEEK_CUR`)
+ * :const:`2` -- relative to the end of the file (:const:`SEEK_END`)
+
+ The default for *start* is 0, which means to start at the beginning of the file.
+ The default for *length* is 0 which means to lock to the end of the file. The
+ default for *whence* is also 0.
+
+Examples (all on a SVR4 compliant system)::
+
+ import struct, fcntl, os
+
+ f = open(...)
+ rv = fcntl.fcntl(f, fcntl.F_SETFL, os.O_NDELAY)
+
+ lockdata = struct.pack('hhllhh', fcntl.F_WRLCK, 0, 0, 0, 0, 0)
+ rv = fcntl.fcntl(f, fcntl.F_SETLKW, lockdata)
+
+Note that in the first example the return value variable *rv* will hold an
+integer value; in the second example it will hold a string value. The structure
+lay-out for the *lockdata* variable is system dependent --- therefore using the
+:func:`flock` call may be better.
+
+
+.. seealso::
+
+ Module :mod:`os`
+ If the locking flags :const:`O_SHLOCK` and :const:`O_EXLOCK` are present
+ in the :mod:`os` module, the :func:`os.open` function provides a more
+ platform-independent alternative to the :func:`lockf` and :func:`flock`
+ functions.
+
diff --git a/Doc/library/filecmp.rst b/Doc/library/filecmp.rst
new file mode 100644
index 0000000000..600421412d
--- /dev/null
+++ b/Doc/library/filecmp.rst
@@ -0,0 +1,152 @@
+
+:mod:`filecmp` --- File and Directory Comparisons
+=================================================
+
+.. module:: filecmp
+ :synopsis: Compare files efficiently.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`filecmp` module defines functions to compare files and directories,
+with various optional time/correctness trade-offs.
+
+The :mod:`filecmp` module defines the following functions:
+
+
+.. function:: cmp(f1, f2[, shallow])
+
+ Compare the files named *f1* and *f2*, returning ``True`` if they seem equal,
+ ``False`` otherwise.
+
+ Unless *shallow* is given and is false, files with identical :func:`os.stat`
+ signatures are taken to be equal.
+
+ Files that were compared using this function will not be compared again unless
+ their :func:`os.stat` signature changes.
+
+ Note that no external programs are called from this function, giving it
+ portability and efficiency.
+
+
+.. function:: cmpfiles(dir1, dir2, common[, shallow])
+
+ Returns three lists of file names: *match*, *mismatch*, *errors*. *match*
+ contains the list of files match in both directories, *mismatch* includes the
+ names of those that don't, and *errros* lists the names of files which could not
+ be compared. Files may be listed in *errors* because the user may lack
+ permission to read them or many other reasons, but always that the comparison
+ could not be done for some reason.
+
+ The *common* parameter is a list of file names found in both directories. The
+ *shallow* parameter has the same meaning and default value as for
+ :func:`filecmp.cmp`.
+
+Example::
+
+ >>> import filecmp
+ >>> filecmp.cmp('undoc.rst', 'undoc.rst')
+ True
+ >>> filecmp.cmp('undoc.rst', 'index.rst')
+ False
+
+
+.. _dircmp-objects:
+
+The :class:`dircmp` class
+-------------------------
+
+:class:`dircmp` instances are built using this constructor:
+
+
+.. class:: dircmp(a, b[, ignore[, hide]])
+
+ Construct a new directory comparison object, to compare the directories *a* and
+ *b*. *ignore* is a list of names to ignore, and defaults to ``['RCS', 'CVS',
+ 'tags']``. *hide* is a list of names to hide, and defaults to ``[os.curdir,
+ os.pardir]``.
+
+The :class:`dircmp` class provides the following methods:
+
+
+.. method:: dircmp.report()
+
+ Print (to ``sys.stdout``) a comparison between *a* and *b*.
+
+
+.. method:: dircmp.report_partial_closure()
+
+ Print a comparison between *a* and *b* and common immediate subdirectories.
+
+
+.. method:: dircmp.report_full_closure()
+
+ Print a comparison between *a* and *b* and common subdirectories (recursively).
+
+The :class:`dircmp` offers a number of interesting attributes that may be used
+to get various bits of information about the directory trees being compared.
+
+Note that via :meth:`__getattr__` hooks, all attributes are computed lazily, so
+there is no speed penalty if only those attributes which are lightweight to
+compute are used.
+
+
+.. attribute:: dircmp.left_list
+
+ Files and subdirectories in *a*, filtered by *hide* and *ignore*.
+
+
+.. attribute:: dircmp.right_list
+
+ Files and subdirectories in *b*, filtered by *hide* and *ignore*.
+
+
+.. attribute:: dircmp.common
+
+ Files and subdirectories in both *a* and *b*.
+
+
+.. attribute:: dircmp.left_only
+
+ Files and subdirectories only in *a*.
+
+
+.. attribute:: dircmp.right_only
+
+ Files and subdirectories only in *b*.
+
+
+.. attribute:: dircmp.common_dirs
+
+ Subdirectories in both *a* and *b*.
+
+
+.. attribute:: dircmp.common_files
+
+ Files in both *a* and *b*
+
+
+.. attribute:: dircmp.common_funny
+
+ Names in both *a* and *b*, such that the type differs between the directories,
+ or names for which :func:`os.stat` reports an error.
+
+
+.. attribute:: dircmp.same_files
+
+ Files which are identical in both *a* and *b*.
+
+
+.. attribute:: dircmp.diff_files
+
+ Files which are in both *a* and *b*, whose contents differ.
+
+
+.. attribute:: dircmp.funny_files
+
+ Files which are in both *a* and *b*, but could not be compared.
+
+
+.. attribute:: dircmp.subdirs
+
+ A dictionary mapping names in :attr:`common_dirs` to :class:`dircmp` objects.
+
diff --git a/Doc/library/fileformats.rst b/Doc/library/fileformats.rst
new file mode 100644
index 0000000000..c0c2eedb6c
--- /dev/null
+++ b/Doc/library/fileformats.rst
@@ -0,0 +1,18 @@
+
+.. _fileformats:
+
+************
+File Formats
+************
+
+The modules described in this chapter parse various miscellaneous file formats
+that aren't markup languages or are related to e-mail.
+
+
+.. toctree::
+
+ csv.rst
+ configparser.rst
+ robotparser.rst
+ netrc.rst
+ xdrlib.rst
diff --git a/Doc/library/fileinput.rst b/Doc/library/fileinput.rst
new file mode 100644
index 0000000000..d0a3ed903f
--- /dev/null
+++ b/Doc/library/fileinput.rst
@@ -0,0 +1,183 @@
+:mod:`fileinput` --- Iterate over lines from multiple input streams
+===================================================================
+
+.. module:: fileinput
+ :synopsis: Loop over standard input or a list of files.
+.. moduleauthor:: Guido van Rossum <guido@python.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+This module implements a helper class and functions to quickly write a loop over
+standard input or a list of files.
+
+The typical use is::
+
+ import fileinput
+ for line in fileinput.input():
+ process(line)
+
+This iterates over the lines of all files listed in ``sys.argv[1:]``, defaulting
+to ``sys.stdin`` if the list is empty. If a filename is ``'-'``, it is also
+replaced by ``sys.stdin``. To specify an alternative list of filenames, pass it
+as the first argument to :func:`input`. A single file name is also allowed.
+
+All files are opened in text mode by default, but you can override this by
+specifying the *mode* parameter in the call to :func:`input` or
+:class:`FileInput()`. If an I/O error occurs during opening or reading a file,
+:exc:`IOError` is raised.
+
+If ``sys.stdin`` is used more than once, the second and further use will return
+no lines, except perhaps for interactive use, or if it has been explicitly reset
+(e.g. using ``sys.stdin.seek(0)``).
+
+Empty files are opened and immediately closed; the only time their presence in
+the list of filenames is noticeable at all is when the last file opened is
+empty.
+
+Lines are returned with any newlines intact, which means that the last line in
+a file may not have one.
+
+You can control how files are opened by providing an opening hook via the
+*openhook* parameter to :func:`fileinput.input` or :class:`FileInput()`. The
+hook must be a function that takes two arguments, *filename* and *mode*, and
+returns an accordingly opened file-like object. Two useful hooks are already
+provided by this module.
+
+The following function is the primary interface of this module:
+
+
+.. function:: input([files[, inplace[, backup[, mode[, openhook]]]]])
+
+ Create an instance of the :class:`FileInput` class. The instance will be used
+ as global state for the functions of this module, and is also returned to use
+ during iteration. The parameters to this function will be passed along to the
+ constructor of the :class:`FileInput` class.
+
+ .. versionchanged:: 2.5
+ Added the *mode* and *openhook* parameters.
+
+The following functions use the global state created by :func:`fileinput.input`;
+if there is no active state, :exc:`RuntimeError` is raised.
+
+
+.. function:: filename()
+
+ Return the name of the file currently being read. Before the first line has
+ been read, returns ``None``.
+
+
+.. function:: fileno()
+
+ Return the integer "file descriptor" for the current file. When no file is
+ opened (before the first line and between files), returns ``-1``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: lineno()
+
+ Return the cumulative line number of the line that has just been read. Before
+ the first line has been read, returns ``0``. After the last line of the last
+ file has been read, returns the line number of that line.
+
+
+.. function:: filelineno()
+
+ Return the line number in the current file. Before the first line has been
+ read, returns ``0``. After the last line of the last file has been read,
+ returns the line number of that line within the file.
+
+
+.. function:: isfirstline()
+
+ Returns true if the line just read is the first line of its file, otherwise
+ returns false.
+
+
+.. function:: isstdin()
+
+ Returns true if the last line was read from ``sys.stdin``, otherwise returns
+ false.
+
+
+.. function:: nextfile()
+
+ Close the current file so that the next iteration will read the first line from
+ the next file (if any); lines not read from the file will not count towards the
+ cumulative line count. The filename is not changed until after the first line
+ of the next file has been read. Before the first line has been read, this
+ function has no effect; it cannot be used to skip the first file. After the
+ last line of the last file has been read, this function has no effect.
+
+
+.. function:: close()
+
+ Close the sequence.
+
+The class which implements the sequence behavior provided by the module is
+available for subclassing as well:
+
+
+.. class:: FileInput([files[, inplace[, backup[, mode[, openhook]]]]])
+
+ Class :class:`FileInput` is the implementation; its methods :meth:`filename`,
+ :meth:`fileno`, :meth:`lineno`, :meth:`filelineno`, :meth:`isfirstline`,
+ :meth:`isstdin`, :meth:`nextfile` and :meth:`close` correspond to the functions
+ of the same name in the module. In addition it has a :meth:`readline` method
+ which returns the next input line, and a :meth:`__getitem__` method which
+ implements the sequence behavior. The sequence must be accessed in strictly
+ sequential order; random access and :meth:`readline` cannot be mixed.
+
+ With *mode* you can specify which file mode will be passed to :func:`open`. It
+ must be one of ``'r'``, ``'rU'``, ``'U'`` and ``'rb'``.
+
+ The *openhook*, when given, must be a function that takes two arguments,
+ *filename* and *mode*, and returns an accordingly opened file-like object. You
+ cannot use *inplace* and *openhook* together.
+
+ .. versionchanged:: 2.5
+ Added the *mode* and *openhook* parameters.
+
+**Optional in-place filtering:** if the keyword argument ``inplace=1`` is passed
+to :func:`fileinput.input` or to the :class:`FileInput` constructor, the file is
+moved to a backup file and standard output is directed to the input file (if a
+file of the same name as the backup file already exists, it will be replaced
+silently). This makes it possible to write a filter that rewrites its input
+file in place. If the *backup* parameter is given (typically as
+``backup='.<some extension>'``), it specifies the extension for the backup file,
+and the backup file remains around; by default, the extension is ``'.bak'`` and
+it is deleted when the output file is closed. In-place filtering is disabled
+when standard input is read.
+
+**Caveat:** The current implementation does not work for MS-DOS 8+3 filesystems.
+
+The two following opening hooks are provided by this module:
+
+
+.. function:: hook_compressed(filename, mode)
+
+ Transparently opens files compressed with gzip and bzip2 (recognized by the
+ extensions ``'.gz'`` and ``'.bz2'``) using the :mod:`gzip` and :mod:`bz2`
+ modules. If the filename extension is not ``'.gz'`` or ``'.bz2'``, the file is
+ opened normally (ie, using :func:`open` without any decompression).
+
+ Usage example: ``fi = fileinput.FileInput(openhook=fileinput.hook_compressed)``
+
+ .. versionadded:: 2.5
+
+
+.. function:: hook_encoded(encoding)
+
+ Returns a hook which opens each file with :func:`codecs.open`, using the given
+ *encoding* to read the file.
+
+ Usage example: ``fi =
+ fileinput.FileInput(openhook=fileinput.hook_encoded("iso-8859-1"))``
+
+ .. note::
+
+ With this hook, :class:`FileInput` might return Unicode strings depending on the
+ specified *encoding*.
+
+ .. versionadded:: 2.5
+
diff --git a/Doc/library/filesys.rst b/Doc/library/filesys.rst
new file mode 100644
index 0000000000..e5b5e44cc1
--- /dev/null
+++ b/Doc/library/filesys.rst
@@ -0,0 +1,38 @@
+
+.. _filesys:
+
+*************************
+File and Directory Access
+*************************
+
+The modules described in this chapter deal with disk files and directories. For
+example, there are modules for reading the properties of files, manipulating
+paths in a portable way, and creating temporary files. The full list of modules
+in this chapter is:
+
+
+.. toctree::
+
+ os.path.rst
+ fileinput.rst
+ stat.rst
+ statvfs.rst
+ filecmp.rst
+ tempfile.rst
+ glob.rst
+ fnmatch.rst
+ linecache.rst
+ shutil.rst
+ dircache.rst
+ macpath.rst
+
+
+.. seealso::
+
+ Section :ref:`bltin-file-objects`
+ A description of Python's built-in file objects.
+
+ Module :mod:`os`
+ Operating system interfaces, including functions to work with files at a lower
+ level than the built-in file object.
+
diff --git a/Doc/library/fnmatch.rst b/Doc/library/fnmatch.rst
new file mode 100644
index 0000000000..244bad9b88
--- /dev/null
+++ b/Doc/library/fnmatch.rst
@@ -0,0 +1,91 @@
+
+:mod:`fnmatch` --- Unix filename pattern matching
+=================================================
+
+.. module:: fnmatch
+ :synopsis: Unix shell style filename pattern matching.
+
+
+.. index:: single: filenames; wildcard expansion
+
+.. index:: module: re
+
+This module provides support for Unix shell-style wildcards, which are *not* the
+same as regular expressions (which are documented in the :mod:`re` module). The
+special characters used in shell-style wildcards are:
+
++------------+------------------------------------+
+| Pattern | Meaning |
++============+====================================+
+| ``*`` | matches everything |
++------------+------------------------------------+
+| ``?`` | matches any single character |
++------------+------------------------------------+
+| ``[seq]`` | matches any character in *seq* |
++------------+------------------------------------+
+| ``[!seq]`` | matches any character not in *seq* |
++------------+------------------------------------+
+
+.. index:: module: glob
+
+Note that the filename separator (``'/'`` on Unix) is *not* special to this
+module. See module :mod:`glob` for pathname expansion (:mod:`glob` uses
+:func:`fnmatch` to match pathname segments). Similarly, filenames starting with
+a period are not special for this module, and are matched by the ``*`` and ``?``
+patterns.
+
+
+.. function:: fnmatch(filename, pattern)
+
+ Test whether the *filename* string matches the *pattern* string, returning true
+ or false. If the operating system is case-insensitive, then both parameters
+ will be normalized to all lower- or upper-case before the comparison is
+ performed. If you require a case-sensitive comparison regardless of whether
+ that's standard for your operating system, use :func:`fnmatchcase` instead.
+
+ This example will print all file names in the current directory with the
+ extension ``.txt``::
+
+ import fnmatch
+ import os
+
+ for file in os.listdir('.'):
+ if fnmatch.fnmatch(file, '*.txt'):
+ print file
+
+
+.. function:: fnmatchcase(filename, pattern)
+
+ Test whether *filename* matches *pattern*, returning true or false; the
+ comparison is case-sensitive.
+
+
+.. function:: filter(names, pattern)
+
+ Return the subset of the list of *names* that match *pattern*. It is the same as
+ ``[n for n in names if fnmatch(n, pattern)]``, but implemented more efficiently.
+
+ .. versionadded:: 2.2
+
+
+.. function:: translate(pattern)
+
+ Return the shell-style *pattern* converted to a regular expression.
+
+ Example::
+
+ >>> import fnmatch, re
+ >>>
+ >>> regex = fnmatch.translate('*.txt')
+ >>> regex
+ '.*\\.txt$'
+ >>> reobj = re.compile(regex)
+ >>> print reobj.match('foobar.txt')
+ <_sre.SRE_Match object at 0x...>
+
+
+.. seealso::
+
+ Module :mod:`glob`
+ Unix shell-style path expansion.
+
diff --git a/Doc/library/formatter.rst b/Doc/library/formatter.rst
new file mode 100644
index 0000000000..2774a2bda6
--- /dev/null
+++ b/Doc/library/formatter.rst
@@ -0,0 +1,350 @@
+
+:mod:`formatter` --- Generic output formatting
+==============================================
+
+.. module:: formatter
+ :synopsis: Generic output formatter and device interface.
+
+
+.. index:: single: HTMLParser (class in htmllib)
+
+This module supports two interface definitions, each with multiple
+implementations. The *formatter* interface is used by the :class:`HTMLParser`
+class of the :mod:`htmllib` module, and the *writer* interface is required by
+the formatter interface.
+
+Formatter objects transform an abstract flow of formatting events into specific
+output events on writer objects. Formatters manage several stack structures to
+allow various properties of a writer object to be changed and restored; writers
+need not be able to handle relative changes nor any sort of "change back"
+operation. Specific writer properties which may be controlled via formatter
+objects are horizontal alignment, font, and left margin indentations. A
+mechanism is provided which supports providing arbitrary, non-exclusive style
+settings to a writer as well. Additional interfaces facilitate formatting
+events which are not reversible, such as paragraph separation.
+
+Writer objects encapsulate device interfaces. Abstract devices, such as file
+formats, are supported as well as physical devices. The provided
+implementations all work with abstract devices. The interface makes available
+mechanisms for setting the properties which formatter objects manage and
+inserting data into the output.
+
+
+.. _formatter-interface:
+
+The Formatter Interface
+-----------------------
+
+Interfaces to create formatters are dependent on the specific formatter class
+being instantiated. The interfaces described below are the required interfaces
+which all formatters must support once initialized.
+
+One data element is defined at the module level:
+
+
+.. data:: AS_IS
+
+ Value which can be used in the font specification passed to the ``push_font()``
+ method described below, or as the new value to any other ``push_property()``
+ method. Pushing the ``AS_IS`` value allows the corresponding ``pop_property()``
+ method to be called without having to track whether the property was changed.
+
+The following attributes are defined for formatter instance objects:
+
+
+.. attribute:: formatter.writer
+
+ The writer instance with which the formatter interacts.
+
+
+.. method:: formatter.end_paragraph(blanklines)
+
+ Close any open paragraphs and insert at least *blanklines* before the next
+ paragraph.
+
+
+.. method:: formatter.add_line_break()
+
+ Add a hard line break if one does not already exist. This does not break the
+ logical paragraph.
+
+
+.. method:: formatter.add_hor_rule(*args, **kw)
+
+ Insert a horizontal rule in the output. A hard break is inserted if there is
+ data in the current paragraph, but the logical paragraph is not broken. The
+ arguments and keywords are passed on to the writer's :meth:`send_line_break`
+ method.
+
+
+.. method:: formatter.add_flowing_data(data)
+
+ Provide data which should be formatted with collapsed whitespace. Whitespace
+ from preceding and successive calls to :meth:`add_flowing_data` is considered as
+ well when the whitespace collapse is performed. The data which is passed to
+ this method is expected to be word-wrapped by the output device. Note that any
+ word-wrapping still must be performed by the writer object due to the need to
+ rely on device and font information.
+
+
+.. method:: formatter.add_literal_data(data)
+
+ Provide data which should be passed to the writer unchanged. Whitespace,
+ including newline and tab characters, are considered legal in the value of
+ *data*.
+
+
+.. method:: formatter.add_label_data(format, counter)
+
+ Insert a label which should be placed to the left of the current left margin.
+ This should be used for constructing bulleted or numbered lists. If the
+ *format* value is a string, it is interpreted as a format specification for
+ *counter*, which should be an integer. The result of this formatting becomes the
+ value of the label; if *format* is not a string it is used as the label value
+ directly. The label value is passed as the only argument to the writer's
+ :meth:`send_label_data` method. Interpretation of non-string label values is
+ dependent on the associated writer.
+
+ Format specifications are strings which, in combination with a counter value,
+ are used to compute label values. Each character in the format string is copied
+ to the label value, with some characters recognized to indicate a transform on
+ the counter value. Specifically, the character ``'1'`` represents the counter
+ value formatter as an Arabic number, the characters ``'A'`` and ``'a'``
+ represent alphabetic representations of the counter value in upper and lower
+ case, respectively, and ``'I'`` and ``'i'`` represent the counter value in Roman
+ numerals, in upper and lower case. Note that the alphabetic and roman
+ transforms require that the counter value be greater than zero.
+
+
+.. method:: formatter.flush_softspace()
+
+ Send any pending whitespace buffered from a previous call to
+ :meth:`add_flowing_data` to the associated writer object. This should be called
+ before any direct manipulation of the writer object.
+
+
+.. method:: formatter.push_alignment(align)
+
+ Push a new alignment setting onto the alignment stack. This may be
+ :const:`AS_IS` if no change is desired. If the alignment value is changed from
+ the previous setting, the writer's :meth:`new_alignment` method is called with
+ the *align* value.
+
+
+.. method:: formatter.pop_alignment()
+
+ Restore the previous alignment.
+
+
+.. method:: formatter.push_font((size, italic, bold, teletype))
+
+ Change some or all font properties of the writer object. Properties which are
+ not set to :const:`AS_IS` are set to the values passed in while others are
+ maintained at their current settings. The writer's :meth:`new_font` method is
+ called with the fully resolved font specification.
+
+
+.. method:: formatter.pop_font()
+
+ Restore the previous font.
+
+
+.. method:: formatter.push_margin(margin)
+
+ Increase the number of left margin indentations by one, associating the logical
+ tag *margin* with the new indentation. The initial margin level is ``0``.
+ Changed values of the logical tag must be true values; false values other than
+ :const:`AS_IS` are not sufficient to change the margin.
+
+
+.. method:: formatter.pop_margin()
+
+ Restore the previous margin.
+
+
+.. method:: formatter.push_style(*styles)
+
+ Push any number of arbitrary style specifications. All styles are pushed onto
+ the styles stack in order. A tuple representing the entire stack, including
+ :const:`AS_IS` values, is passed to the writer's :meth:`new_styles` method.
+
+
+.. method:: formatter.pop_style([n=1])
+
+ Pop the last *n* style specifications passed to :meth:`push_style`. A tuple
+ representing the revised stack, including :const:`AS_IS` values, is passed to
+ the writer's :meth:`new_styles` method.
+
+
+.. method:: formatter.set_spacing(spacing)
+
+ Set the spacing style for the writer.
+
+
+.. method:: formatter.assert_line_data([flag=1])
+
+ Inform the formatter that data has been added to the current paragraph
+ out-of-band. This should be used when the writer has been manipulated
+ directly. The optional *flag* argument can be set to false if the writer
+ manipulations produced a hard line break at the end of the output.
+
+
+.. _formatter-impls:
+
+Formatter Implementations
+-------------------------
+
+Two implementations of formatter objects are provided by this module. Most
+applications may use one of these classes without modification or subclassing.
+
+
+.. class:: NullFormatter([writer])
+
+ A formatter which does nothing. If *writer* is omitted, a :class:`NullWriter`
+ instance is created. No methods of the writer are called by
+ :class:`NullFormatter` instances. Implementations should inherit from this
+ class if implementing a writer interface but don't need to inherit any
+ implementation.
+
+
+.. class:: AbstractFormatter(writer)
+
+ The standard formatter. This implementation has demonstrated wide applicability
+ to many writers, and may be used directly in most circumstances. It has been
+ used to implement a full-featured World Wide Web browser.
+
+
+.. _writer-interface:
+
+The Writer Interface
+--------------------
+
+Interfaces to create writers are dependent on the specific writer class being
+instantiated. The interfaces described below are the required interfaces which
+all writers must support once initialized. Note that while most applications can
+use the :class:`AbstractFormatter` class as a formatter, the writer must
+typically be provided by the application.
+
+
+.. method:: writer.flush()
+
+ Flush any buffered output or device control events.
+
+
+.. method:: writer.new_alignment(align)
+
+ Set the alignment style. The *align* value can be any object, but by convention
+ is a string or ``None``, where ``None`` indicates that the writer's "preferred"
+ alignment should be used. Conventional *align* values are ``'left'``,
+ ``'center'``, ``'right'``, and ``'justify'``.
+
+
+.. method:: writer.new_font(font)
+
+ Set the font style. The value of *font* will be ``None``, indicating that the
+ device's default font should be used, or a tuple of the form ``(``*size*,
+ *italic*, *bold*, *teletype*``)``. Size will be a string indicating the size of
+ font that should be used; specific strings and their interpretation must be
+ defined by the application. The *italic*, *bold*, and *teletype* values are
+ Boolean values specifying which of those font attributes should be used.
+
+
+.. method:: writer.new_margin(margin, level)
+
+ Set the margin level to the integer *level* and the logical tag to *margin*.
+ Interpretation of the logical tag is at the writer's discretion; the only
+ restriction on the value of the logical tag is that it not be a false value for
+ non-zero values of *level*.
+
+
+.. method:: writer.new_spacing(spacing)
+
+ Set the spacing style to *spacing*.
+
+
+.. method:: writer.new_styles(styles)
+
+ Set additional styles. The *styles* value is a tuple of arbitrary values; the
+ value :const:`AS_IS` should be ignored. The *styles* tuple may be interpreted
+ either as a set or as a stack depending on the requirements of the application
+ and writer implementation.
+
+
+.. method:: writer.send_line_break()
+
+ Break the current line.
+
+
+.. method:: writer.send_paragraph(blankline)
+
+ Produce a paragraph separation of at least *blankline* blank lines, or the
+ equivalent. The *blankline* value will be an integer. Note that the
+ implementation will receive a call to :meth:`send_line_break` before this call
+ if a line break is needed; this method should not include ending the last line
+ of the paragraph. It is only responsible for vertical spacing between
+ paragraphs.
+
+
+.. method:: writer.send_hor_rule(*args, **kw)
+
+ Display a horizontal rule on the output device. The arguments to this method
+ are entirely application- and writer-specific, and should be interpreted with
+ care. The method implementation may assume that a line break has already been
+ issued via :meth:`send_line_break`.
+
+
+.. method:: writer.send_flowing_data(data)
+
+ Output character data which may be word-wrapped and re-flowed as needed. Within
+ any sequence of calls to this method, the writer may assume that spans of
+ multiple whitespace characters have been collapsed to single space characters.
+
+
+.. method:: writer.send_literal_data(data)
+
+ Output character data which has already been formatted for display. Generally,
+ this should be interpreted to mean that line breaks indicated by newline
+ characters should be preserved and no new line breaks should be introduced. The
+ data may contain embedded newline and tab characters, unlike data provided to
+ the :meth:`send_formatted_data` interface.
+
+
+.. method:: writer.send_label_data(data)
+
+ Set *data* to the left of the current left margin, if possible. The value of
+ *data* is not restricted; treatment of non-string values is entirely
+ application- and writer-dependent. This method will only be called at the
+ beginning of a line.
+
+
+.. _writer-impls:
+
+Writer Implementations
+----------------------
+
+Three implementations of the writer object interface are provided as examples by
+this module. Most applications will need to derive new writer classes from the
+:class:`NullWriter` class.
+
+
+.. class:: NullWriter()
+
+ A writer which only provides the interface definition; no actions are taken on
+ any methods. This should be the base class for all writers which do not need to
+ inherit any implementation methods.
+
+
+.. class:: AbstractWriter()
+
+ A writer which can be used in debugging formatters, but not much else. Each
+ method simply announces itself by printing its name and arguments on standard
+ output.
+
+
+.. class:: DumbWriter([file[, maxcol=72]])
+
+ Simple writer class which writes output on the file object passed in as *file*
+ or, if *file* is omitted, on standard output. The output is simply word-wrapped
+ to the number of columns specified by *maxcol*. This class is suitable for
+ reflowing a sequence of paragraphs.
+
diff --git a/Doc/library/fpectl.rst b/Doc/library/fpectl.rst
new file mode 100644
index 0000000000..ef030f0034
--- /dev/null
+++ b/Doc/library/fpectl.rst
@@ -0,0 +1,120 @@
+
+:mod:`fpectl` --- Floating point exception control
+==================================================
+
+.. module:: fpectl
+ :platform: Unix
+ :synopsis: Provide control for floating point exception handling.
+.. moduleauthor:: Lee Busby <busby1@llnl.gov>
+.. sectionauthor:: Lee Busby <busby1@llnl.gov>
+
+
+.. note::
+
+ The :mod:`fpectl` module is not built by default, and its usage is discouraged
+ and may be dangerous except in the hands of experts. See also the section
+ :ref:`fpectl-limitations` on limitations for more details.
+
+.. index:: single: IEEE-754
+
+Most computers carry out floating point operations in conformance with the
+so-called IEEE-754 standard. On any real computer, some floating point
+operations produce results that cannot be expressed as a normal floating point
+value. For example, try ::
+
+ >>> import math
+ >>> math.exp(1000)
+ inf
+ >>> math.exp(1000) / math.exp(1000)
+ nan
+
+(The example above will work on many platforms. DEC Alpha may be one exception.)
+"Inf" is a special, non-numeric value in IEEE-754 that stands for "infinity",
+and "nan" means "not a number." Note that, other than the non-numeric results,
+nothing special happened when you asked Python to carry out those calculations.
+That is in fact the default behaviour prescribed in the IEEE-754 standard, and
+if it works for you, stop reading now.
+
+In some circumstances, it would be better to raise an exception and stop
+processing at the point where the faulty operation was attempted. The
+:mod:`fpectl` module is for use in that situation. It provides control over
+floating point units from several hardware manufacturers, allowing the user to
+turn on the generation of :const:`SIGFPE` whenever any of the IEEE-754
+exceptions Division by Zero, Overflow, or Invalid Operation occurs. In tandem
+with a pair of wrapper macros that are inserted into the C code comprising your
+python system, :const:`SIGFPE` is trapped and converted into the Python
+:exc:`FloatingPointError` exception.
+
+The :mod:`fpectl` module defines the following functions and may raise the given
+exception:
+
+
+.. function:: turnon_sigfpe()
+
+ Turn on the generation of :const:`SIGFPE`, and set up an appropriate signal
+ handler.
+
+
+.. function:: turnoff_sigfpe()
+
+ Reset default handling of floating point exceptions.
+
+
+.. exception:: FloatingPointError
+
+ After :func:`turnon_sigfpe` has been executed, a floating point operation that
+ raises one of the IEEE-754 exceptions Division by Zero, Overflow, or Invalid
+ operation will in turn raise this standard Python exception.
+
+
+.. _fpectl-example:
+
+Example
+-------
+
+The following example demonstrates how to start up and test operation of the
+:mod:`fpectl` module. ::
+
+ >>> import fpectl
+ >>> import fpetest
+ >>> fpectl.turnon_sigfpe()
+ >>> fpetest.test()
+ overflow PASS
+ FloatingPointError: Overflow
+
+ div by 0 PASS
+ FloatingPointError: Division by zero
+ [ more output from test elided ]
+ >>> import math
+ >>> math.exp(1000)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ FloatingPointError: in math_1
+
+
+.. _fpectl-limitations:
+
+Limitations and other considerations
+------------------------------------
+
+Setting up a given processor to trap IEEE-754 floating point errors currently
+requires custom code on a per-architecture basis. You may have to modify
+:mod:`fpectl` to control your particular hardware.
+
+Conversion of an IEEE-754 exception to a Python exception requires that the
+wrapper macros ``PyFPE_START_PROTECT`` and ``PyFPE_END_PROTECT`` be inserted
+into your code in an appropriate fashion. Python itself has been modified to
+support the :mod:`fpectl` module, but many other codes of interest to numerical
+analysts have not.
+
+The :mod:`fpectl` module is not thread-safe.
+
+
+.. seealso::
+
+ Some files in the source distribution may be interesting in learning more about
+ how this module operates. The include file :file:`Include/pyfpe.h` discusses the
+ implementation of this module at some length. :file:`Modules/fpetestmodule.c`
+ gives several examples of use. Many additional examples can be found in
+ :file:`Objects/floatobject.c`.
+
diff --git a/Doc/library/fpformat.rst b/Doc/library/fpformat.rst
new file mode 100644
index 0000000000..33655fbf01
--- /dev/null
+++ b/Doc/library/fpformat.rst
@@ -0,0 +1,56 @@
+
+:mod:`fpformat` --- Floating point conversions
+==============================================
+
+.. module:: fpformat
+ :synopsis: General floating point formatting functions.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`fpformat` module defines functions for dealing with floating point
+numbers representations in 100% pure Python.
+
+.. note::
+
+ This module is unneeded: everything here could be done via the ``%`` string
+ interpolation operator.
+
+The :mod:`fpformat` module defines the following functions and an exception:
+
+
+.. function:: fix(x, digs)
+
+ Format *x* as ``[-]ddd.ddd`` with *digs* digits after the point and at least one
+ digit before. If ``digs <= 0``, the decimal point is suppressed.
+
+ *x* can be either a number or a string that looks like one. *digs* is an
+ integer.
+
+ Return value is a string.
+
+
+.. function:: sci(x, digs)
+
+ Format *x* as ``[-]d.dddE[+-]ddd`` with *digs* digits after the point and
+ exactly one digit before. If ``digs <= 0``, one digit is kept and the point is
+ suppressed.
+
+ *x* can be either a real number, or a string that looks like one. *digs* is an
+ integer.
+
+ Return value is a string.
+
+
+.. exception:: NotANumber
+
+ Exception raised when a string passed to :func:`fix` or :func:`sci` as the *x*
+ parameter does not look like a number. This is a subclass of :exc:`ValueError`
+ when the standard exceptions are strings. The exception value is the improperly
+ formatted string that caused the exception to be raised.
+
+Example::
+
+ >>> import fpformat
+ >>> fpformat.fix(1.23, 1)
+ '1.2'
+
diff --git a/Doc/library/framework.rst b/Doc/library/framework.rst
new file mode 100644
index 0000000000..c665fb7001
--- /dev/null
+++ b/Doc/library/framework.rst
@@ -0,0 +1,335 @@
+
+:mod:`FrameWork` --- Interactive application framework
+======================================================
+
+.. module:: FrameWork
+ :platform: Mac
+ :synopsis: Interactive application framework.
+
+
+The :mod:`FrameWork` module contains classes that together provide a framework
+for an interactive Macintosh application. The programmer builds an application
+by creating subclasses that override various methods of the bases classes,
+thereby implementing the functionality wanted. Overriding functionality can
+often be done on various different levels, i.e. to handle clicks in a single
+dialog window in a non-standard way it is not necessary to override the complete
+event handling.
+
+Work on the :mod:`FrameWork` has pretty much stopped, now that :mod:`PyObjC` is
+available for full Cocoa access from Python, and the documentation describes
+only the most important functionality, and not in the most logical manner at
+that. Examine the source or the examples for more details. The following are
+some comments posted on the MacPython newsgroup about the strengths and
+limitations of :mod:`FrameWork`:
+
+
+.. epigraph::
+
+ The strong point of :mod:`FrameWork` is that it allows you to break into the
+ control-flow at many different places. :mod:`W`, for instance, uses a different
+ way to enable/disable menus and that plugs right in leaving the rest intact.
+ The weak points of :mod:`FrameWork` are that it has no abstract command
+ interface (but that shouldn't be difficult), that its dialog support is minimal
+ and that its control/toolbar support is non-existent.
+
+The :mod:`FrameWork` module defines the following functions:
+
+
+.. function:: Application()
+
+ An object representing the complete application. See below for a description of
+ the methods. The default :meth:`__init__` routine creates an empty window
+ dictionary and a menu bar with an apple menu.
+
+
+.. function:: MenuBar()
+
+ An object representing the menubar. This object is usually not created by the
+ user.
+
+
+.. function:: Menu(bar, title[, after])
+
+ An object representing a menu. Upon creation you pass the ``MenuBar`` the menu
+ appears in, the *title* string and a position (1-based) *after* where the menu
+ should appear (default: at the end).
+
+
+.. function:: MenuItem(menu, title[, shortcut, callback])
+
+ Create a menu item object. The arguments are the menu to create, the item title
+ string and optionally the keyboard shortcut and a callback routine. The callback
+ is called with the arguments menu-id, item number within menu (1-based), current
+ front window and the event record.
+
+ Instead of a callable object the callback can also be a string. In this case
+ menu selection causes the lookup of a method in the topmost window and the
+ application. The method name is the callback string with ``'domenu_'``
+ prepended.
+
+ Calling the ``MenuBar`` :meth:`fixmenudimstate` method sets the correct dimming
+ for all menu items based on the current front window.
+
+
+.. function:: Separator(menu)
+
+ Add a separator to the end of a menu.
+
+
+.. function:: SubMenu(menu, label)
+
+ Create a submenu named *label* under menu *menu*. The menu object is returned.
+
+
+.. function:: Window(parent)
+
+ Creates a (modeless) window. *Parent* is the application object to which the
+ window belongs. The window is not displayed until later.
+
+
+.. function:: DialogWindow(parent)
+
+ Creates a modeless dialog window.
+
+
+.. function:: windowbounds(width, height)
+
+ Return a ``(left, top, right, bottom)`` tuple suitable for creation of a window
+ of given width and height. The window will be staggered with respect to previous
+ windows, and an attempt is made to keep the whole window on-screen. However, the
+ window will however always be the exact size given, so parts may be offscreen.
+
+
+.. function:: setwatchcursor()
+
+ Set the mouse cursor to a watch.
+
+
+.. function:: setarrowcursor()
+
+ Set the mouse cursor to an arrow.
+
+
+.. _application-objects:
+
+Application Objects
+-------------------
+
+Application objects have the following methods, among others:
+
+
+.. method:: Application.makeusermenus()
+
+ Override this method if you need menus in your application. Append the menus to
+ the attribute :attr:`menubar`.
+
+
+.. method:: Application.getabouttext()
+
+ Override this method to return a text string describing your application.
+ Alternatively, override the :meth:`do_about` method for more elaborate "about"
+ messages.
+
+
+.. method:: Application.mainloop([mask[, wait]])
+
+ This routine is the main event loop, call it to set your application rolling.
+ *Mask* is the mask of events you want to handle, *wait* is the number of ticks
+ you want to leave to other concurrent application (default 0, which is probably
+ not a good idea). While raising *self* to exit the mainloop is still supported
+ it is not recommended: call ``self._quit()`` instead.
+
+ The event loop is split into many small parts, each of which can be overridden.
+ The default methods take care of dispatching events to windows and dialogs,
+ handling drags and resizes, Apple Events, events for non-FrameWork windows, etc.
+
+ In general, all event handlers should return ``1`` if the event is fully handled
+ and ``0`` otherwise (because the front window was not a FrameWork window, for
+ instance). This is needed so that update events and such can be passed on to
+ other windows like the Sioux console window. Calling :func:`MacOS.HandleEvent`
+ is not allowed within *our_dispatch* or its callees, since this may result in an
+ infinite loop if the code is called through the Python inner-loop event handler.
+
+
+.. method:: Application.asyncevents(onoff)
+
+ Call this method with a nonzero parameter to enable asynchronous event handling.
+ This will tell the inner interpreter loop to call the application event handler
+ *async_dispatch* whenever events are available. This will cause FrameWork window
+ updates and the user interface to remain working during long computations, but
+ will slow the interpreter down and may cause surprising results in non-reentrant
+ code (such as FrameWork itself). By default *async_dispatch* will immediately
+ call *our_dispatch* but you may override this to handle only certain events
+ asynchronously. Events you do not handle will be passed to Sioux and such.
+
+ The old on/off value is returned.
+
+
+.. method:: Application._quit()
+
+ Terminate the running :meth:`mainloop` call at the next convenient moment.
+
+
+.. method:: Application.do_char(c, event)
+
+ The user typed character *c*. The complete details of the event can be found in
+ the *event* structure. This method can also be provided in a ``Window`` object,
+ which overrides the application-wide handler if the window is frontmost.
+
+
+.. method:: Application.do_dialogevent(event)
+
+ Called early in the event loop to handle modeless dialog events. The default
+ method simply dispatches the event to the relevant dialog (not through the
+ ``DialogWindow`` object involved). Override if you need special handling of
+ dialog events (keyboard shortcuts, etc).
+
+
+.. method:: Application.idle(event)
+
+ Called by the main event loop when no events are available. The null-event is
+ passed (so you can look at mouse position, etc).
+
+
+.. _window-objects:
+
+Window Objects
+--------------
+
+Window objects have the following methods, among others:
+
+
+.. method:: Window.open()
+
+ Override this method to open a window. Store the MacOS window-id in
+ :attr:`self.wid` and call the :meth:`do_postopen` method to register the window
+ with the parent application.
+
+
+.. method:: Window.close()
+
+ Override this method to do any special processing on window close. Call the
+ :meth:`do_postclose` method to cleanup the parent state.
+
+
+.. method:: Window.do_postresize(width, height, macoswindowid)
+
+ Called after the window is resized. Override if more needs to be done than
+ calling ``InvalRect``.
+
+
+.. method:: Window.do_contentclick(local, modifiers, event)
+
+ The user clicked in the content part of a window. The arguments are the
+ coordinates (window-relative), the key modifiers and the raw event.
+
+
+.. method:: Window.do_update(macoswindowid, event)
+
+ An update event for the window was received. Redraw the window.
+
+
+.. method:: Window.do_activate(activate, event)
+
+ The window was activated (``activate == 1``) or deactivated (``activate == 0``).
+ Handle things like focus highlighting, etc.
+
+
+.. _controlswindow-object:
+
+ControlsWindow Object
+---------------------
+
+ControlsWindow objects have the following methods besides those of ``Window``
+objects:
+
+
+.. method:: ControlsWindow.do_controlhit(window, control, pcode, event)
+
+ Part *pcode* of control *control* was hit by the user. Tracking and such has
+ already been taken care of.
+
+
+.. _scrolledwindow-object:
+
+ScrolledWindow Object
+---------------------
+
+ScrolledWindow objects are ControlsWindow objects with the following extra
+methods:
+
+
+.. method:: ScrolledWindow.scrollbars([wantx[, wanty]])
+
+ Create (or destroy) horizontal and vertical scrollbars. The arguments specify
+ which you want (default: both). The scrollbars always have minimum ``0`` and
+ maximum ``32767``.
+
+
+.. method:: ScrolledWindow.getscrollbarvalues()
+
+ You must supply this method. It should return a tuple ``(x, y)`` giving the
+ current position of the scrollbars (between ``0`` and ``32767``). You can return
+ ``None`` for either to indicate the whole document is visible in that direction.
+
+
+.. method:: ScrolledWindow.updatescrollbars()
+
+ Call this method when the document has changed. It will call
+ :meth:`getscrollbarvalues` and update the scrollbars.
+
+
+.. method:: ScrolledWindow.scrollbar_callback(which, what, value)
+
+ Supplied by you and called after user interaction. *which* will be ``'x'`` or
+ ``'y'``, *what* will be ``'-'``, ``'--'``, ``'set'``, ``'++'`` or ``'+'``. For
+ ``'set'``, *value* will contain the new scrollbar position.
+
+
+.. method:: ScrolledWindow.scalebarvalues(absmin, absmax, curmin, curmax)
+
+ Auxiliary method to help you calculate values to return from
+ :meth:`getscrollbarvalues`. You pass document minimum and maximum value and
+ topmost (leftmost) and bottommost (rightmost) visible values and it returns the
+ correct number or ``None``.
+
+
+.. method:: ScrolledWindow.do_activate(onoff, event)
+
+ Takes care of dimming/highlighting scrollbars when a window becomes frontmost.
+ If you override this method, call this one at the end of your method.
+
+
+.. method:: ScrolledWindow.do_postresize(width, height, window)
+
+ Moves scrollbars to the correct position. Call this method initially if you
+ override it.
+
+
+.. method:: ScrolledWindow.do_controlhit(window, control, pcode, event)
+
+ Handles scrollbar interaction. If you override it call this method first, a
+ nonzero return value indicates the hit was in the scrollbars and has been
+ handled.
+
+
+.. _dialogwindow-objects:
+
+DialogWindow Objects
+--------------------
+
+DialogWindow objects have the following methods besides those of ``Window``
+objects:
+
+
+.. method:: DialogWindow.open(resid)
+
+ Create the dialog window, from the DLOG resource with id *resid*. The dialog
+ object is stored in :attr:`self.wid`.
+
+
+.. method:: DialogWindow.do_itemhit(item, event)
+
+ Item number *item* was hit. You are responsible for redrawing toggle buttons,
+ etc.
+
diff --git a/Doc/library/frameworks.rst b/Doc/library/frameworks.rst
new file mode 100644
index 0000000000..5d8dad5578
--- /dev/null
+++ b/Doc/library/frameworks.rst
@@ -0,0 +1,18 @@
+
+.. _frameworks:
+
+******************
+Program Frameworks
+******************
+
+The modules described in this chapter are frameworks that will largely dictate
+the structure of your program. Currently the modules described here are all
+oriented toward writing command-line interfaces.
+
+The full list of modules described in this chapter is:
+
+
+.. toctree::
+
+ cmd.rst
+ shlex.rst
diff --git a/Doc/library/ftplib.rst b/Doc/library/ftplib.rst
new file mode 100644
index 0000000000..60e88cf1fa
--- /dev/null
+++ b/Doc/library/ftplib.rst
@@ -0,0 +1,320 @@
+
+:mod:`ftplib` --- FTP protocol client
+=====================================
+
+.. module:: ftplib
+ :synopsis: FTP protocol client (requires sockets).
+
+
+.. index::
+ pair: FTP; protocol
+ single: FTP; ftplib (standard module)
+
+This module defines the class :class:`FTP` and a few related items. The
+:class:`FTP` class implements the client side of the FTP protocol. You can use
+this to write Python programs that perform a variety of automated FTP jobs, such
+as mirroring other ftp servers. It is also used by the module :mod:`urllib` to
+handle URLs that use FTP. For more information on FTP (File Transfer Protocol),
+see Internet :rfc:`959`.
+
+Here's a sample session using the :mod:`ftplib` module::
+
+ >>> from ftplib import FTP
+ >>> ftp = FTP('ftp.cwi.nl') # connect to host, default port
+ >>> ftp.login() # user anonymous, passwd anonymous@
+ >>> ftp.retrlines('LIST') # list directory contents
+ total 24418
+ drwxrwsr-x 5 ftp-usr pdmaint 1536 Mar 20 09:48 .
+ dr-xr-srwt 105 ftp-usr pdmaint 1536 Mar 21 14:32 ..
+ -rw-r--r-- 1 ftp-usr pdmaint 5305 Mar 20 09:48 INDEX
+ .
+ .
+ .
+ >>> ftp.retrbinary('RETR README', open('README', 'wb').write)
+ '226 Transfer complete.'
+ >>> ftp.quit()
+
+The module defines the following items:
+
+
+.. class:: FTP([host[, user[, passwd[, acct[, timeout]]]]])
+
+ Return a new instance of the :class:`FTP` class. When *host* is given, the
+ method call ``connect(host)`` is made. When *user* is given, additionally the
+ method call ``login(user, passwd, acct)`` is made (where *passwd* and *acct*
+ default to the empty string when not given). The optional *timeout* parameter
+ specifies a timeout in seconds for the connection attempt (if is not specified,
+ or passed as None, the global default timeout setting will be used).
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. data:: all_errors
+
+ The set of all exceptions (as a tuple) that methods of :class:`FTP` instances
+ may raise as a result of problems with the FTP connection (as opposed to
+ programming errors made by the caller). This set includes the four exceptions
+ listed below as well as :exc:`socket.error` and :exc:`IOError`.
+
+
+.. exception:: error_reply
+
+ Exception raised when an unexpected reply is received from the server.
+
+
+.. exception:: error_temp
+
+ Exception raised when an error code in the range 400--499 is received.
+
+
+.. exception:: error_perm
+
+ Exception raised when an error code in the range 500--599 is received.
+
+
+.. exception:: error_proto
+
+ Exception raised when a reply is received from the server that does not begin
+ with a digit in the range 1--5.
+
+
+.. seealso::
+
+ Module :mod:`netrc`
+ Parser for the :file:`.netrc` file format. The file :file:`.netrc` is typically
+ used by FTP clients to load user authentication information before prompting the
+ user.
+
+ .. index:: single: ftpmirror.py
+
+ The file :file:`Tools/scripts/ftpmirror.py` in the Python source distribution is
+ a script that can mirror FTP sites, or portions thereof, using the :mod:`ftplib`
+ module. It can be used as an extended example that applies this module.
+
+
+.. _ftp-objects:
+
+FTP Objects
+-----------
+
+Several methods are available in two flavors: one for handling text files and
+another for binary files. These are named for the command which is used
+followed by ``lines`` for the text version or ``binary`` for the binary version.
+
+:class:`FTP` instances have the following methods:
+
+
+.. method:: FTP.set_debuglevel(level)
+
+ Set the instance's debugging level. This controls the amount of debugging
+ output printed. The default, ``0``, produces no debugging output. A value of
+ ``1`` produces a moderate amount of debugging output, generally a single line
+ per request. A value of ``2`` or higher produces the maximum amount of
+ debugging output, logging each line sent and received on the control connection.
+
+
+.. method:: FTP.connect(host[, port[, timeout]])
+
+ Connect to the given host and port. The default port number is ``21``, as
+ specified by the FTP protocol specification. It is rarely needed to specify a
+ different port number. This function should be called only once for each
+ instance; it should not be called at all if a host was given when the instance
+ was created. All other methods can only be used after a connection has been
+ made.
+
+ The optional *timeout* parameter specifies a timeout in seconds for the
+ connection attempt. If is not specified, or passed as None, the object timeout
+ is used (the timeout that you passed when instantiating the class); if the
+ object timeout is also None, the global default timeout setting will be used.
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. method:: FTP.getwelcome()
+
+ Return the welcome message sent by the server in reply to the initial
+ connection. (This message sometimes contains disclaimers or help information
+ that may be relevant to the user.)
+
+
+.. method:: FTP.login([user[, passwd[, acct]]])
+
+ Log in as the given *user*. The *passwd* and *acct* parameters are optional and
+ default to the empty string. If no *user* is specified, it defaults to
+ ``'anonymous'``. If *user* is ``'anonymous'``, the default *passwd* is
+ ``'anonymous@'``. This function should be called only once for each instance,
+ after a connection has been established; it should not be called at all if a
+ host and user were given when the instance was created. Most FTP commands are
+ only allowed after the client has logged in.
+
+
+.. method:: FTP.abort()
+
+ Abort a file transfer that is in progress. Using this does not always work, but
+ it's worth a try.
+
+
+.. method:: FTP.sendcmd(command)
+
+ Send a simple command string to the server and return the response string.
+
+
+.. method:: FTP.voidcmd(command)
+
+ Send a simple command string to the server and handle the response. Return
+ nothing if a response code in the range 200--299 is received. Raise an exception
+ otherwise.
+
+
+.. method:: FTP.retrbinary(command, callback[, maxblocksize[, rest]])
+
+ Retrieve a file in binary transfer mode. *command* should be an appropriate
+ ``RETR`` command: ``'RETR filename'``. The *callback* function is called for
+ each block of data received, with a single string argument giving the data
+ block. The optional *maxblocksize* argument specifies the maximum chunk size to
+ read on the low-level socket object created to do the actual transfer (which
+ will also be the largest size of the data blocks passed to *callback*). A
+ reasonable default is chosen. *rest* means the same thing as in the
+ :meth:`transfercmd` method.
+
+
+.. method:: FTP.retrlines(command[, callback])
+
+ Retrieve a file or directory listing in ASCII transfer mode. *command* should be
+ an appropriate ``RETR`` command (see :meth:`retrbinary`) or a ``LIST`` command
+ (usually just the string ``'LIST'``). The *callback* function is called for
+ each line, with the trailing CRLF stripped. The default *callback* prints the
+ line to ``sys.stdout``.
+
+
+.. method:: FTP.set_pasv(boolean)
+
+ Enable "passive" mode if *boolean* is true, other disable passive mode. (In
+ Python 2.0 and before, passive mode was off by default; in Python 2.1 and later,
+ it is on by default.)
+
+
+.. method:: FTP.storbinary(command, file[, blocksize])
+
+ Store a file in binary transfer mode. *command* should be an appropriate
+ ``STOR`` command: ``"STOR filename"``. *file* is an open file object which is
+ read until EOF using its :meth:`read` method in blocks of size *blocksize* to
+ provide the data to be stored. The *blocksize* argument defaults to 8192.
+
+ .. versionchanged:: 2.1
+ default for *blocksize* added.
+
+
+.. method:: FTP.storlines(command, file)
+
+ Store a file in ASCII transfer mode. *command* should be an appropriate
+ ``STOR`` command (see :meth:`storbinary`). Lines are read until EOF from the
+ open file object *file* using its :meth:`readline` method to provide the data to
+ be stored.
+
+
+.. method:: FTP.transfercmd(cmd[, rest])
+
+ Initiate a transfer over the data connection. If the transfer is active, send a
+ ``EPRT`` or ``PORT`` command and the transfer command specified by *cmd*, and
+ accept the connection. If the server is passive, send a ``EPSV`` or ``PASV``
+ command, connect to it, and start the transfer command. Either way, return the
+ socket for the connection.
+
+ If optional *rest* is given, a ``REST`` command is sent to the server, passing
+ *rest* as an argument. *rest* is usually a byte offset into the requested file,
+ telling the server to restart sending the file's bytes at the requested offset,
+ skipping over the initial bytes. Note however that RFC 959 requires only that
+ *rest* be a string containing characters in the printable range from ASCII code
+ 33 to ASCII code 126. The :meth:`transfercmd` method, therefore, converts
+ *rest* to a string, but no check is performed on the string's contents. If the
+ server does not recognize the ``REST`` command, an :exc:`error_reply` exception
+ will be raised. If this happens, simply call :meth:`transfercmd` without a
+ *rest* argument.
+
+
+.. method:: FTP.ntransfercmd(cmd[, rest])
+
+ Like :meth:`transfercmd`, but returns a tuple of the data connection and the
+ expected size of the data. If the expected size could not be computed, ``None``
+ will be returned as the expected size. *cmd* and *rest* means the same thing as
+ in :meth:`transfercmd`.
+
+
+.. method:: FTP.nlst(argument[, ...])
+
+ Return a list of files as returned by the ``NLST`` command. The optional
+ *argument* is a directory to list (default is the current server directory).
+ Multiple arguments can be used to pass non-standard options to the ``NLST``
+ command.
+
+
+.. method:: FTP.dir(argument[, ...])
+
+ Produce a directory listing as returned by the ``LIST`` command, printing it to
+ standard output. The optional *argument* is a directory to list (default is the
+ current server directory). Multiple arguments can be used to pass non-standard
+ options to the ``LIST`` command. If the last argument is a function, it is used
+ as a *callback* function as for :meth:`retrlines`; the default prints to
+ ``sys.stdout``. This method returns ``None``.
+
+
+.. method:: FTP.rename(fromname, toname)
+
+ Rename file *fromname* on the server to *toname*.
+
+
+.. method:: FTP.delete(filename)
+
+ Remove the file named *filename* from the server. If successful, returns the
+ text of the response, otherwise raises :exc:`error_perm` on permission errors or
+ :exc:`error_reply` on other errors.
+
+
+.. method:: FTP.cwd(pathname)
+
+ Set the current directory on the server.
+
+
+.. method:: FTP.mkd(pathname)
+
+ Create a new directory on the server.
+
+
+.. method:: FTP.pwd()
+
+ Return the pathname of the current directory on the server.
+
+
+.. method:: FTP.rmd(dirname)
+
+ Remove the directory named *dirname* on the server.
+
+
+.. method:: FTP.size(filename)
+
+ Request the size of the file named *filename* on the server. On success, the
+ size of the file is returned as an integer, otherwise ``None`` is returned.
+ Note that the ``SIZE`` command is not standardized, but is supported by many
+ common server implementations.
+
+
+.. method:: FTP.quit()
+
+ Send a ``QUIT`` command to the server and close the connection. This is the
+ "polite" way to close a connection, but it may raise an exception of the server
+ reponds with an error to the ``QUIT`` command. This implies a call to the
+ :meth:`close` method which renders the :class:`FTP` instance useless for
+ subsequent calls (see below).
+
+
+.. method:: FTP.close()
+
+ Close the connection unilaterally. This should not be applied to an already
+ closed connection such as after a successful call to :meth:`quit`. After this
+ call the :class:`FTP` instance should not be used any more (after a call to
+ :meth:`close` or :meth:`quit` you cannot reopen the connection by issuing
+ another :meth:`login` method).
+
diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst
new file mode 100644
index 0000000000..b0a5577cfd
--- /dev/null
+++ b/Doc/library/functions.rst
@@ -0,0 +1,1138 @@
+
+.. _built-in-funcs:
+
+Built-in Functions
+==================
+
+The Python interpreter has a number of functions built into it that are always
+available. They are listed here in alphabetical order.
+
+
+.. function:: __import__(name[, globals[, locals[, fromlist[, level]]]])
+
+ .. index::
+ statement: import
+ module: ihooks
+ module: rexec
+ module: imp
+
+ .. note::
+
+ This is an advanced function that is not needed in everyday Python
+ programming.
+
+ The function is invoked by the :keyword:`import` statement. It mainly exists
+ so that you can replace it with another function that has a compatible
+ interface, in order to change the semantics of the :keyword:`import` statement.
+ For examples of why and how you would do this, see the standard library modules
+ :mod:`ihooks` and :mod:`rexec`. See also the built-in module :mod:`imp`, which
+ defines some useful operations out of which you can build your own
+ :func:`__import__` function.
+
+ For example, the statement ``import spam`` results in the following call:
+ ``__import__('spam',`` ``globals(),`` ``locals(), [], -1)``; the statement
+ ``from spam.ham import eggs`` results in ``__import__('spam.ham', globals(),
+ locals(), ['eggs'], -1)``. Note that even though ``locals()`` and ``['eggs']``
+ are passed in as arguments, the :func:`__import__` function does not set the
+ local variable named ``eggs``; this is done by subsequent code that is generated
+ for the import statement. (In fact, the standard implementation does not use
+ its *locals* argument at all, and uses its *globals* only to determine the
+ package context of the :keyword:`import` statement.)
+
+ When the *name* variable is of the form ``package.module``, normally, the
+ top-level package (the name up till the first dot) is returned, *not* the
+ module named by *name*. However, when a non-empty *fromlist* argument is
+ given, the module named by *name* is returned. This is done for
+ compatibility with the bytecode generated for the different kinds of import
+ statement; when using ``import spam.ham.eggs``, the top-level package
+ :mod:`spam` must be placed in the importing namespace, but when using ``from
+ spam.ham import eggs``, the ``spam.ham`` subpackage must be used to find the
+ ``eggs`` variable. As a workaround for this behavior, use :func:`getattr` to
+ extract the desired components. For example, you could define the following
+ helper::
+
+ def my_import(name):
+ mod = __import__(name)
+ components = name.split('.')
+ for comp in components[1:]:
+ mod = getattr(mod, comp)
+ return mod
+
+ *level* specifies whether to use absolute or relative imports. The default is
+ ``-1`` which indicates both absolute and relative imports will be attempted.
+ ``0`` means only perform absolute imports. Positive values for *level* indicate
+ the number of parent directories to search relative to the directory of the
+ module calling :func:`__import__`.
+
+ .. versionchanged:: 2.5
+ The level parameter was added.
+
+ .. versionchanged:: 2.5
+ Keyword support for parameters was added.
+
+
+.. function:: abs(x)
+
+ Return the absolute value of a number. The argument may be a plain or long
+ integer or a floating point number. If the argument is a complex number, its
+ magnitude is returned.
+
+
+.. function:: all(iterable)
+
+ Return True if all elements of the *iterable* are true. Equivalent to::
+
+ def all(iterable):
+ for element in iterable:
+ if not element:
+ return False
+ return True
+
+ .. versionadded:: 2.5
+
+
+.. function:: any(iterable)
+
+ Return True if any element of the *iterable* is true. Equivalent to::
+
+ def any(iterable):
+ for element in iterable:
+ if element:
+ return True
+ return False
+
+ .. versionadded:: 2.5
+
+
+.. function:: basestring()
+
+ This abstract type is the superclass for :class:`str`. It
+ cannot be called or instantiated, but it can be used to test whether an object
+ is an instance of :class:`str` (or a user-defined type inherited from
+ :class:`basestring`).
+
+ .. versionadded:: 2.3
+
+
+.. function:: bin(x)
+
+ Convert an integer number to a binary string. The result is a valid Python
+ expression. If *x* is not a Python :class:`int` object, it has to define an
+ :meth:`__index__` method that returns an integer.
+
+ .. versionadded:: 3.0
+
+
+.. function:: bool([x])
+
+ Convert a value to a Boolean, using the standard truth testing procedure. If
+ *x* is false or omitted, this returns :const:`False`; otherwise it returns
+ :const:`True`. :class:`bool` is also a class, which is a subclass of
+ :class:`int`. Class :class:`bool` cannot be subclassed further. Its only
+ instances are :const:`False` and :const:`True`.
+
+ .. index:: pair: Boolean; type
+
+ .. versionadded:: 2.2.1
+
+ .. versionchanged:: 2.3
+ If no argument is given, this function returns :const:`False`.
+
+
+.. function:: chr(i)
+
+ Return the string of one character whose Unicode codepoint is the integer *i*. For
+ example, ``chr(97)`` returns the string ``'a'``. This is the inverse of
+ :func:`ord`. The valid range for the argument depends how Python was
+ configured -- it may be either UCS2 [0..0xFFFF] or UCS4 [0..0x10FFFF].
+ :exc:`ValueError` will be raised if *i* is outside that range.
+
+
+.. function:: classmethod(function)
+
+ Return a class method for *function*.
+
+ A class method receives the class as implicit first argument, just like an
+ instance method receives the instance. To declare a class method, use this
+ idiom::
+
+ class C:
+ @classmethod
+ def f(cls, arg1, arg2, ...): ...
+
+ The ``@classmethod`` form is a function decorator -- see the description of
+ function definitions in :ref:`function` for details.
+
+ It can be called either on the class (such as ``C.f()``) or on an instance (such
+ as ``C().f()``). The instance is ignored except for its class. If a class
+ method is called for a derived class, the derived class object is passed as the
+ implied first argument.
+
+ Class methods are different than C++ or Java static methods. If you want those,
+ see :func:`staticmethod` in this section.
+
+ For more information on class methods, consult the documentation on the standard
+ type hierarchy in :ref:`types`.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.4
+ Function decorator syntax added.
+
+
+.. function:: cmp(x, y)
+
+ Compare the two objects *x* and *y* and return an integer according to the
+ outcome. The return value is negative if ``x < y``, zero if ``x == y`` and
+ strictly positive if ``x > y``.
+
+
+.. function:: compile(source, filename, mode[, flags[, dont_inherit]])
+
+ Compile the *source* into a code object. Code objects can be executed by a call
+ to :func:`exec` or evaluated by a call to :func:`eval`. The *filename* argument
+ should give the file from which the code was read; pass some recognizable value
+ if it wasn't read from a file (``'<string>'`` is commonly used). The *mode*
+ argument specifies what kind of code must be compiled; it can be ``'exec'`` if
+ *source* consists of a sequence of statements, ``'eval'`` if it consists of a
+ single expression, or ``'single'`` if it consists of a single interactive
+ statement (in the latter case, expression statements that evaluate to something
+ else than ``None`` will be printed).
+
+ When compiling multi-line statements, two caveats apply: line endings must be
+ represented by a single newline character (``'\n'``), and the input must be
+ terminated by at least one newline character. If line endings are represented
+ by ``'\r\n'``, use the string :meth:`replace` method to change them into
+ ``'\n'``.
+
+ The optional arguments *flags* and *dont_inherit* (which are new in Python 2.2)
+ control which future statements (see :pep:`236`) affect the compilation of
+ *source*. If neither is present (or both are zero) the code is compiled with
+ those future statements that are in effect in the code that is calling compile.
+ If the *flags* argument is given and *dont_inherit* is not (or is zero) then the
+ future statements specified by the *flags* argument are used in addition to
+ those that would be used anyway. If *dont_inherit* is a non-zero integer then
+ the *flags* argument is it -- the future statements in effect around the call to
+ compile are ignored.
+
+ Future statements are specified by bits which can be bitwise or-ed together to
+ specify multiple statements. The bitfield required to specify a given feature
+ can be found as the :attr:`compiler_flag` attribute on the :class:`_Feature`
+ instance in the :mod:`__future__` module.
+
+
+.. function:: complex([real[, imag]])
+
+ Create a complex number with the value *real* + *imag*\*j or convert a string or
+ number to a complex number. If the first parameter is a string, it will be
+ interpreted as a complex number and the function must be called without a second
+ parameter. The second parameter can never be a string. Each argument may be any
+ numeric type (including complex). If *imag* is omitted, it defaults to zero and
+ the function serves as a numeric conversion function like :func:`int`,
+ :func:`long` and :func:`float`. If both arguments are omitted, returns ``0j``.
+
+ The complex type is described in :ref:`typesnumeric`.
+
+
+.. function:: delattr(object, name)
+
+ This is a relative of :func:`setattr`. The arguments are an object and a
+ string. The string must be the name of one of the object's attributes. The
+ function deletes the named attribute, provided the object allows it. For
+ example, ``delattr(x, 'foobar')`` is equivalent to ``del x.foobar``.
+
+
+.. function:: dict([arg])
+ :noindex:
+
+ Create a new data dictionary, optionally with items taken from *arg*.
+ The dictionary type is described in :ref:`typesmapping`.
+
+ For other containers see the built in :class:`list`, :class:`set`, and
+ :class:`tuple` classes, and the :mod:`collections` module.
+
+
+.. function:: dir([object])
+
+ Without arguments, return the list of names in the current local scope. With an
+ argument, attempt to return a list of valid attributes for that object.
+
+ If the object has a method named :meth:`__dir__`, this method will be called and
+ must return the list of attributes. This allows objects that implement a custom
+ :func:`__getattr__` or :func:`__getattribute__` function to customize the way
+ :func:`dir` reports their attributes.
+
+ If the object does not provide :meth:`__dir__`, the function tries its best to
+ gather information from the object's :attr:`__dict__` attribute, if defined, and
+ from its type object. The resulting list is not necessarily complete, and may
+ be inaccurate when the object has a custom :func:`__getattr__`.
+
+ The default :func:`dir` mechanism behaves differently with different types of
+ objects, as it attempts to produce the most relevant, rather than complete,
+ information:
+
+ * If the object is a module object, the list contains the names of the module's
+ attributes.
+
+ * If the object is a type or class object, the list contains the names of its
+ attributes, and recursively of the attributes of its bases.
+
+ * Otherwise, the list contains the object's attributes' names, the names of its
+ class's attributes, and recursively of the attributes of its class's base
+ classes.
+
+ The resulting list is sorted alphabetically. For example::
+
+ >>> import struct
+ >>> dir()
+ ['__builtins__', '__doc__', '__name__', 'struct']
+ >>> dir(struct)
+ ['__doc__', '__name__', 'calcsize', 'error', 'pack', 'unpack']
+ >>> class Foo(object):
+ ... def __dir__(self):
+ ... return ["kan", "ga", "roo"]
+ ...
+ >>> f = Foo()
+ >>> dir(f)
+ ['ga', 'kan', 'roo']
+
+ .. note::
+
+ Because :func:`dir` is supplied primarily as a convenience for use at an
+ interactive prompt, it tries to supply an interesting set of names more than it
+ tries to supply a rigorously or consistently defined set of names, and its
+ detailed behavior may change across releases.
+
+
+.. function:: divmod(a, b)
+
+ Take two (non complex) numbers as arguments and return a pair of numbers
+ consisting of their quotient and remainder when using long division. With mixed
+ operand types, the rules for binary arithmetic operators apply. For plain and
+ long integers, the result is the same as ``(a // b, a % b)``. For floating point
+ numbers the result is ``(q, a % b)``, where *q* is usually ``math.floor(a / b)``
+ but may be 1 less than that. In any case ``q * b + a % b`` is very close to
+ *a*, if ``a % b`` is non-zero it has the same sign as *b*, and ``0 <= abs(a % b)
+ < abs(b)``.
+
+ .. versionchanged:: 2.3
+ Using :func:`divmod` with complex numbers is deprecated.
+
+
+.. function:: enumerate(iterable)
+
+ Return an enumerate object. *iterable* must be a sequence, an iterator, or some
+ other object which supports iteration. The :meth:`__next__` method of the
+ iterator returned by :func:`enumerate` returns a tuple containing a count (from
+ zero) and the corresponding value obtained from iterating over *iterable*.
+ :func:`enumerate` is useful for obtaining an indexed series: ``(0, seq[0])``,
+ ``(1, seq[1])``, ``(2, seq[2])``, .... For example::
+
+ >>> for i, season in enumerate(['Spring', 'Summer', 'Fall', 'Winter')]:
+ >>> print i, season
+ 0 Spring
+ 1 Summer
+ 2 Fall
+ 3 Winter
+
+ .. versionadded:: 2.3
+
+
+.. function:: eval(expression[, globals[, locals]])
+
+ The arguments are a string and optional globals and locals. If provided,
+ *globals* must be a dictionary. If provided, *locals* can be any mapping
+ object.
+
+ .. versionchanged:: 2.4
+ formerly *locals* was required to be a dictionary.
+
+ The *expression* argument is parsed and evaluated as a Python expression
+ (technically speaking, a condition list) using the *globals* and *locals*
+ dictionaries as global and local name space. If the *globals* dictionary is
+ present and lacks '__builtins__', the current globals are copied into *globals*
+ before *expression* is parsed. This means that *expression* normally has full
+ access to the standard :mod:`__builtin__` module and restricted environments are
+ propagated. If the *locals* dictionary is omitted it defaults to the *globals*
+ dictionary. If both dictionaries are omitted, the expression is executed in the
+ environment where :keyword:`eval` is called. The return value is the result of
+ the evaluated expression. Syntax errors are reported as exceptions. Example::
+
+ >>> x = 1
+ >>> print eval('x+1')
+ 2
+
+ This function can also be used to execute arbitrary code objects (such as those
+ created by :func:`compile`). In this case pass a code object instead of a
+ string. The code object must have been compiled passing ``'eval'`` as the
+ *kind* argument.
+
+ Hints: dynamic execution of statements is supported by the :func:`exec`
+ function. The :func:`globals` and :func:`locals` functions
+ returns the current global and local dictionary, respectively, which may be
+ useful to pass around for use by :func:`eval` or :func:`exec`.
+
+
+.. function:: exec(object[, globals[, locals]])
+
+ This function supports dynamic execution of Python code. *object* must be either
+ a string, an open file object, or a code object. If it is a string, the string
+ is parsed as a suite of Python statements which is then executed (unless a
+ syntax error occurs). If it is an open file, the file is parsed until EOF and
+ executed. If it is a code object, it is simply executed. In all cases, the
+ code that's executed is expected to be valid as file input (see the section
+ "File input" in the Reference Manual). Be aware that the :keyword:`return` and
+ :keyword:`yield` statements may not be used outside of function definitions even
+ within the context of code passed to the :func:`exec` function. The return value
+ is ``None``.
+
+ In all cases, if the optional parts are omitted, the code is executed in the
+ current scope. If only *globals* is provided, it must be a dictionary, which
+ will be used for both the global and the local variables. If *globals* and
+ *locals* are given, they are used for the global and local variables,
+ respectively. If provided, *locals* can be any mapping object.
+
+ If the *globals* dictionary does not contain a value for the key
+ ``__builtins__``, a reference to the dictionary of the built-in module
+ :mod:`__builtin__` is inserted under that key. That way you can control what
+ builtins are available to the executed code by inserting your own
+ ``__builtins__`` dictionary into *globals* before passing it to :func:`exec`.
+
+ .. note::
+
+ The built-in functions :func:`globals` and :func:`locals` return the current
+ global and local dictionary, respectively, which may be useful to pass around
+ for use as the second and third argument to :func:`exec`.
+
+ .. warning::
+
+ The default *locals* act as described for function :func:`locals` below:
+ modifications to the default *locals* dictionary should not be attempted. Pass
+ an explicit *locals* dictionary if you need to see effects of the code on
+ *locals* after function :func:`execfile` returns. :func:`exec` cannot be
+ used reliably to modify a function's locals.
+
+
+.. function:: filter(function, iterable)
+
+ Construct a list from those elements of *iterable* for which *function* returns
+ true. *iterable* may be either a sequence, a container which supports
+ iteration, or an iterator, If *iterable* is a string or a tuple, the result
+ also has that type; otherwise it is always a list. If *function* is ``None``,
+ the identity function is assumed, that is, all elements of *iterable* that are
+ false are removed.
+
+ Note that ``filter(function, iterable)`` is equivalent to ``[item for item in
+ iterable if function(item)]`` if function is not ``None`` and ``[item for item
+ in iterable if item]`` if function is ``None``.
+
+
+.. function:: float([x])
+
+ Convert a string or a number to floating point. If the argument is a string, it
+ must contain a possibly signed decimal or floating point number, possibly
+ embedded in whitespace. Otherwise, the argument may be a plain or long integer
+ or a floating point number, and a floating point number with the same value
+ (within Python's floating point precision) is returned. If no argument is
+ given, returns ``0.0``.
+
+ .. note::
+
+ .. index::
+ single: NaN
+ single: Infinity
+
+ When passing in a string, values for NaN and Infinity may be returned, depending
+ on the underlying C library. The specific set of strings accepted which cause
+ these values to be returned depends entirely on the C library and is known to
+ vary.
+
+ The float type is described in :ref:`typesnumeric`.
+
+.. function:: frozenset([iterable])
+ :noindex:
+
+ Return a frozenset object, optionally with elements taken from *iterable*.
+ The frozenset type is described in :ref:`types-set`.
+
+ For other containers see the built in :class:`dict`, :class:`list`, and
+ :class:`tuple` classes, and the :mod:`collections` module.
+
+ .. versionadded:: 2.4
+
+
+.. function:: getattr(object, name[, default])
+
+ Return the value of the named attributed of *object*. *name* must be a string.
+ If the string is the name of one of the object's attributes, the result is the
+ value of that attribute. For example, ``getattr(x, 'foobar')`` is equivalent to
+ ``x.foobar``. If the named attribute does not exist, *default* is returned if
+ provided, otherwise :exc:`AttributeError` is raised.
+
+
+.. function:: globals()
+
+ Return a dictionary representing the current global symbol table. This is always
+ the dictionary of the current module (inside a function or method, this is the
+ module where it is defined, not the module from which it is called).
+
+
+.. function:: hasattr(object, name)
+
+ The arguments are an object and a string. The result is ``True`` if the string
+ is the name of one of the object's attributes, ``False`` if not. (This is
+ implemented by calling ``getattr(object, name)`` and seeing whether it raises an
+ exception or not.)
+
+
+.. function:: hash(object)
+
+ Return the hash value of the object (if it has one). Hash values are integers.
+ They are used to quickly compare dictionary keys during a dictionary lookup.
+ Numeric values that compare equal have the same hash value (even if they are of
+ different types, as is the case for 1 and 1.0).
+
+
+.. function:: help([object])
+
+ Invoke the built-in help system. (This function is intended for interactive
+ use.) If no argument is given, the interactive help system starts on the
+ interpreter console. If the argument is a string, then the string is looked up
+ as the name of a module, function, class, method, keyword, or documentation
+ topic, and a help page is printed on the console. If the argument is any other
+ kind of object, a help page on the object is generated.
+
+ .. versionadded:: 2.2
+
+
+.. function:: hex(x)
+
+ Convert an integer number to a hexadecimal string. The result is a valid Python
+ expression. If *x* is not a Python :class:`int` object, it has to define an
+ :meth:`__index__` method that returns an integer.
+
+ .. versionchanged:: 2.4
+ Formerly only returned an unsigned literal.
+
+
+.. function:: id(object)
+
+ Return the "identity" of an object. This is an integer (or long integer) which
+ is guaranteed to be unique and constant for this object during its lifetime.
+ Two objects with non-overlapping lifetimes may have the same :func:`id` value.
+ (Implementation note: this is the address of the object.)
+
+
+.. function:: int([x[, radix]])
+
+ Convert a string or number to an integer. If the argument is a string, it
+ must contain a possibly signed number of arbitrary size,
+ possibly embedded in whitespace. The *radix* parameter gives the base for the
+ conversion and may be any integer in the range [2, 36], or zero. If *radix* is
+ zero, the interpretation is the same as for integer literals. If *radix* is
+ specified and *x* is not a string, :exc:`TypeError` is raised. Otherwise, the
+ argument may be another integer, a floating point number or any other object
+ that has an :meth:`__int__` method. Conversion
+ of floating point numbers to integers truncates (towards zero). If no
+ arguments are given, returns ``0``.
+
+ The integer type is described in :ref:`typesnumeric`.
+
+
+.. function:: isinstance(object, classinfo)
+
+ Return true if the *object* argument is an instance of the *classinfo* argument,
+ or of a (direct or indirect) subclass thereof. Also return true if *classinfo*
+ is a type object (new-style class) and *object* is an object of that type or of
+ a (direct or indirect) subclass thereof. If *object* is not a class instance or
+ an object of the given type, the function always returns false. If *classinfo*
+ is neither a class object nor a type object, it may be a tuple of class or type
+ objects, or may recursively contain other such tuples (other sequence types are
+ not accepted). If *classinfo* is not a class, type, or tuple of classes, types,
+ and such tuples, a :exc:`TypeError` exception is raised.
+
+ .. versionchanged:: 2.2
+ Support for a tuple of type information was added.
+
+
+.. function:: issubclass(class, classinfo)
+
+ Return true if *class* is a subclass (direct or indirect) of *classinfo*. A
+ class is considered a subclass of itself. *classinfo* may be a tuple of class
+ objects, in which case every entry in *classinfo* will be checked. In any other
+ case, a :exc:`TypeError` exception is raised.
+
+ .. versionchanged:: 2.3
+ Support for a tuple of type information was added.
+
+
+.. function:: iter(o[, sentinel])
+
+ Return an iterator object. The first argument is interpreted very differently
+ depending on the presence of the second argument. Without a second argument, *o*
+ must be a collection object which supports the iteration protocol (the
+ :meth:`__iter__` method), or it must support the sequence protocol (the
+ :meth:`__getitem__` method with integer arguments starting at ``0``). If it
+ does not support either of those protocols, :exc:`TypeError` is raised. If the
+ second argument, *sentinel*, is given, then *o* must be a callable object. The
+ iterator created in this case will call *o* with no arguments for each call to
+ its :meth:`__next__` method; if the value returned is equal to *sentinel*,
+ :exc:`StopIteration` will be raised, otherwise the value will be returned.
+
+ .. versionadded:: 2.2
+
+
+.. function:: len(s)
+
+ Return the length (the number of items) of an object. The argument may be a
+ sequence (string, tuple or list) or a mapping (dictionary).
+
+
+.. function:: list([iterable])
+
+ Return a list whose items are the same and in the same order as *iterable*'s
+ items. *iterable* may be either a sequence, a container that supports
+ iteration, or an iterator object. If *iterable* is already a list, a copy is
+ made and returned, similar to ``iterable[:]``. For instance, ``list('abc')``
+ returns ``['a', 'b', 'c']`` and ``list( (1, 2, 3) )`` returns ``[1, 2, 3]``. If
+ no argument is given, returns a new empty list, ``[]``.
+
+ :class:`list` is a mutable sequence type, as documented in
+ :ref:`typesseq`. For other containers see the built in :class:`dict`,
+ :class:`set`, and :class:`tuple` classes, and the :mod:`collections` module.
+
+
+.. function:: locals()
+
+ Update and return a dictionary representing the current local symbol table.
+
+ .. warning::
+
+ The contents of this dictionary should not be modified; changes may not affect
+ the values of local variables used by the interpreter.
+
+ Free variables are returned by *locals* when it is called in a function block.
+ Modifications of free variables may not affect the values used by the
+ interpreter. Free variables are not returned in class blocks.
+
+
+.. function:: map(function, iterable, ...)
+
+ Apply *function* to every item of *iterable* and return a list of the results.
+ If additional *iterable* arguments are passed, *function* must take that many
+ arguments and is applied to the items from all iterables in parallel. If one
+ iterable is shorter than another it is assumed to be extended with ``None``
+ items. If *function* is ``None``, the identity function is assumed; if there
+ are multiple arguments, :func:`map` returns a list consisting of tuples
+ containing the corresponding items from all iterables (a kind of transpose
+ operation). The *iterable* arguments may be a sequence or any iterable object;
+ the result is always a list.
+
+
+.. function:: max(iterable[, args...][key])
+
+ With a single argument *iterable*, return the largest item of a non-empty
+ iterable (such as a string, tuple or list). With more than one argument, return
+ the largest of the arguments.
+
+ The optional *key* argument specifies a one-argument ordering function like that
+ used for :meth:`list.sort`. The *key* argument, if supplied, must be in keyword
+ form (for example, ``max(a,b,c,key=func)``).
+
+ .. versionchanged:: 2.5
+ Added support for the optional *key* argument.
+
+
+.. function:: min(iterable[, args...][key])
+
+ With a single argument *iterable*, return the smallest item of a non-empty
+ iterable (such as a string, tuple or list). With more than one argument, return
+ the smallest of the arguments.
+
+ The optional *key* argument specifies a one-argument ordering function like that
+ used for :meth:`list.sort`. The *key* argument, if supplied, must be in keyword
+ form (for example, ``min(a,b,c,key=func)``).
+
+ .. versionchanged:: 2.5
+ Added support for the optional *key* argument.
+
+
+.. function:: next(iterator[, default])
+
+ Retrieve the next item from the *iterable* by calling its :meth:`__next__`
+ method. If *default* is given, it is returned if the iterator is exhausted,
+ otherwise :exc:`StopIteration` is raised.
+
+
+.. function:: object()
+
+ Return a new featureless object. :class:`object` is a base for all new style
+ classes. It has the methods that are common to all instances of new style
+ classes.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.3
+ This function does not accept any arguments. Formerly, it accepted arguments but
+ ignored them.
+
+
+.. function:: oct(x)
+
+ Convert an integer number to an octal string. The result is a valid Python
+ expression. If *x* is not a Python :class:`int` object, it has to define an
+ :meth:`__index__` method that returns an integer.
+
+ .. versionchanged:: 2.4
+ Formerly only returned an unsigned literal.
+
+
+.. function:: open(filename[, mode[, bufsize]])
+
+ Open a file, returning an object of the :class:`file` type described in
+ section :ref:`bltin-file-objects`. If the file cannot be opened,
+ :exc:`IOError` is raised. When opening a file, it's preferable to use
+ :func:`open` instead of invoking the :class:`file` constructor directly.
+
+ The first two arguments are the same as for ``stdio``'s :cfunc:`fopen`:
+ *filename* is the file name to be opened, and *mode* is a string indicating how
+ the file is to be opened.
+
+ The most commonly-used values of *mode* are ``'r'`` for reading, ``'w'`` for
+ writing (truncating the file if it already exists), and ``'a'`` for appending
+ (which on *some* Unix systems means that *all* writes append to the end of the
+ file regardless of the current seek position). If *mode* is omitted, it
+ defaults to ``'r'``. When opening a binary file, you should append ``'b'`` to
+ the *mode* value to open the file in binary mode, which will improve
+ portability. (Appending ``'b'`` is useful even on systems that don't treat
+ binary and text files differently, where it serves as documentation.) See below
+ for more possible values of *mode*.
+
+ .. index::
+ single: line-buffered I/O
+ single: unbuffered I/O
+ single: buffer size, I/O
+ single: I/O control; buffering
+
+ The optional *bufsize* argument specifies the file's desired buffer size: 0
+ means unbuffered, 1 means line buffered, any other positive value means use a
+ buffer of (approximately) that size. A negative *bufsize* means to use the
+ system default, which is usually line buffered for tty devices and fully
+ buffered for other files. If omitted, the system default is used. [#]_
+
+ Modes ``'r+'``, ``'w+'`` and ``'a+'`` open the file for updating (note that
+ ``'w+'`` truncates the file). Append ``'b'`` to the mode to open the file in
+ binary mode, on systems that differentiate between binary and text files; on
+ systems that don't have this distinction, adding the ``'b'`` has no effect.
+
+ In addition to the standard :cfunc:`fopen` values *mode* may be ``'U'`` or
+ ``'rU'``. Python is usually built with universal newline support; supplying
+ ``'U'`` opens the file as a text file, but lines may be terminated by any of the
+ following: the Unix end-of-line convention ``'\n'``, the Macintosh convention
+ ``'\r'``, or the Windows convention ``'\r\n'``. All of these external
+ representations are seen as ``'\n'`` by the Python program. If Python is built
+ without universal newline support a *mode* with ``'U'`` is the same as normal
+ text mode. Note that file objects so opened also have an attribute called
+ :attr:`newlines` which has a value of ``None`` (if no newlines have yet been
+ seen), ``'\n'``, ``'\r'``, ``'\r\n'``, or a tuple containing all the newline
+ types seen.
+
+ Python enforces that the mode, after stripping ``'U'``, begins with ``'r'``,
+ ``'w'`` or ``'a'``.
+
+ See also the :mod:`fileinput` module.
+
+ .. versionchanged:: 2.5
+ Restriction on first letter of mode string introduced.
+
+
+.. function:: ord(c)
+
+ Given a string of length one, return an integer representing the Unicode code
+ point of the character when the argument is a unicode object, or the value of
+ the byte when the argument is an 8-bit string. For example, ``ord('a')`` returns
+ the integer ``97``, ``ord(u'\u2020')`` returns ``8224``. This is the inverse of
+ :func:`chr` for 8-bit strings and of :func:`unichr` for unicode objects. If a
+ unicode argument is given and Python was built with UCS2 Unicode, then the
+ character's code point must be in the range [0..65535] inclusive; otherwise the
+ string length is two, and a :exc:`TypeError` will be raised.
+
+
+.. function:: pow(x, y[, z])
+
+ Return *x* to the power *y*; if *z* is present, return *x* to the power *y*,
+ modulo *z* (computed more efficiently than ``pow(x, y) % z``). The two-argument
+ form ``pow(x, y)`` is equivalent to using the power operator: ``x**y``.
+
+ The arguments must have numeric types. With mixed operand types, the coercion
+ rules for binary arithmetic operators apply. For int and long int operands, the
+ result has the same type as the operands (after coercion) unless the second
+ argument is negative; in that case, all arguments are converted to float and a
+ float result is delivered. For example, ``10**2`` returns ``100``, but
+ ``10**-2`` returns ``0.01``. (This last feature was added in Python 2.2. In
+ Python 2.1 and before, if both arguments were of integer types and the second
+ argument was negative, an exception was raised.) If the second argument is
+ negative, the third argument must be omitted. If *z* is present, *x* and *y*
+ must be of integer types, and *y* must be non-negative. (This restriction was
+ added in Python 2.2. In Python 2.1 and before, floating 3-argument ``pow()``
+ returned platform-dependent results depending on floating-point rounding
+ accidents.)
+
+
+.. function:: property([fget[, fset[, fdel[, doc]]]])
+
+ Return a property attribute for new-style classes (classes that derive from
+ :class:`object`).
+
+ *fget* is a function for getting an attribute value, likewise *fset* is a
+ function for setting, and *fdel* a function for del'ing, an attribute. Typical
+ use is to define a managed attribute x::
+
+ class C(object):
+ def __init__(self): self._x = None
+ def getx(self): return self._x
+ def setx(self, value): self._x = value
+ def delx(self): del self._x
+ x = property(getx, setx, delx, "I'm the 'x' property.")
+
+ If given, *doc* will be the docstring of the property attribute. Otherwise, the
+ property will copy *fget*'s docstring (if it exists). This makes it possible to
+ create read-only properties easily using :func:`property` as a decorator::
+
+ class Parrot(object):
+ def __init__(self):
+ self._voltage = 100000
+
+ @property
+ def voltage(self):
+ """Get the current voltage."""
+ return self._voltage
+
+ turns the :meth:`voltage` method into a "getter" for a read-only attribute with
+ the same name.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.5
+ Use *fget*'s docstring if no *doc* given.
+
+
+.. function:: range([start,] stop[, step])
+
+ This is a versatile function to create sequences containing arithmetic
+ progressions. It is most often used in :keyword:`for` loops. The arguments
+ must be plain integers. If the *step* argument is omitted, it defaults to
+ ``1``. If the *start* argument is omitted, it defaults to ``0``. The full form
+ returns a list of plain integers ``[start, start + step, start + 2 * step,
+ ...]``. If *step* is positive, the last element is the largest ``start + i *
+ step`` less than *stop*; if *step* is negative, the last element is the smallest
+ ``start + i * step`` greater than *stop*. *step* must not be zero (or else
+ :exc:`ValueError` is raised). Example::
+
+ >>> list(range(10))
+ [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+ >>> list(range(1, 11))
+ [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+ >>> list(range(0, 30, 5))
+ [0, 5, 10, 15, 20, 25]
+ >>> list(range(0, 10, 3))
+ [0, 3, 6, 9]
+ >>> list(range(0, -10, -1))
+ [0, -1, -2, -3, -4, -5, -6, -7, -8, -9]
+ >>> list(range(0))
+ []
+ >>> list(range(1, 0))
+ []
+
+
+.. function:: repr(object)
+
+ Return a string containing a printable representation of an object. This is the
+ same value yielded by conversions (reverse quotes). It is sometimes useful to be
+ able to access this operation as an ordinary function. For many types, this
+ function makes an attempt to return a string that would yield an object with the
+ same value when passed to :func:`eval`.
+
+
+.. function:: reversed(seq)
+
+ Return a reverse iterator. *seq* must be an object which supports the sequence
+ protocol (the :meth:`__len__` method and the :meth:`__getitem__` method with
+ integer arguments starting at ``0``).
+
+ .. versionadded:: 2.4
+
+
+.. function:: round(x[, n])
+
+ Return the floating point value *x* rounded to *n* digits after the decimal
+ point. If *n* is omitted, it defaults to zero. The result is a floating point
+ number. Values are rounded to the closest multiple of 10 to the power minus
+ *n*; if two multiples are equally close, rounding is done away from 0 (so. for
+ example, ``round(0.5)`` is ``1.0`` and ``round(-0.5)`` is ``-1.0``).
+
+
+.. function:: set([iterable])
+ :noindex:
+
+ Return a new set, optionally with elements are taken from *iterable*.
+ The set type is described in :ref:`types-set`.
+
+ For other containers see the built in :class:`dict`, :class:`list`, and
+ :class:`tuple` classes, and the :mod:`collections` module.
+
+ .. versionadded:: 2.4
+
+
+.. function:: setattr(object, name, value)
+
+ This is the counterpart of :func:`getattr`. The arguments are an object, a
+ string and an arbitrary value. The string may name an existing attribute or a
+ new attribute. The function assigns the value to the attribute, provided the
+ object allows it. For example, ``setattr(x, 'foobar', 123)`` is equivalent to
+ ``x.foobar = 123``.
+
+
+.. function:: slice([start,] stop[, step])
+
+ .. index:: single: Numerical Python
+
+ Return a slice object representing the set of indices specified by
+ ``range(start, stop, step)``. The *start* and *step* arguments default to
+ ``None``. Slice objects have read-only data attributes :attr:`start`,
+ :attr:`stop` and :attr:`step` which merely return the argument values (or their
+ default). They have no other explicit functionality; however they are used by
+ Numerical Python and other third party extensions. Slice objects are also
+ generated when extended indexing syntax is used. For example:
+ ``a[start:stop:step]`` or ``a[start:stop, i]``.
+
+
+.. function:: sorted(iterable[, cmp[, key[, reverse]]])
+
+ Return a new sorted list from the items in *iterable*.
+
+ The optional arguments *cmp*, *key*, and *reverse* have the same meaning as
+ those for the :meth:`list.sort` method (described in section
+ :ref:`typesseq-mutable`).
+
+ *cmp* specifies a custom comparison function of two arguments (iterable
+ elements) which should return a negative, zero or positive number depending on
+ whether the first argument is considered smaller than, equal to, or larger than
+ the second argument: ``cmp=lambda x,y: cmp(x.lower(), y.lower())``
+
+ *key* specifies a function of one argument that is used to extract a comparison
+ key from each list element: ``key=str.lower``
+
+ *reverse* is a boolean value. If set to ``True``, then the list elements are
+ sorted as if each comparison were reversed.
+
+ In general, the *key* and *reverse* conversion processes are much faster than
+ specifying an equivalent *cmp* function. This is because *cmp* is called
+ multiple times for each list element while *key* and *reverse* touch each
+ element only once.
+
+ .. versionadded:: 2.4
+
+
+.. function:: staticmethod(function)
+
+ Return a static method for *function*.
+
+ A static method does not receive an implicit first argument. To declare a static
+ method, use this idiom::
+
+ class C:
+ @staticmethod
+ def f(arg1, arg2, ...): ...
+
+ The ``@staticmethod`` form is a function decorator -- see the description of
+ function definitions in :ref:`function` for details.
+
+ It can be called either on the class (such as ``C.f()``) or on an instance (such
+ as ``C().f()``). The instance is ignored except for its class.
+
+ Static methods in Python are similar to those found in Java or C++. For a more
+ advanced concept, see :func:`classmethod` in this section.
+
+ For more information on static methods, consult the documentation on the
+ standard type hierarchy in :ref:`types`.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.4
+ Function decorator syntax added.
+
+
+.. function:: str([object[, encoding[, errors]]])
+
+ Return a string version of an object, using one of the following modes:
+
+ If *encoding* and/or *errors* are given, :func:`str` will decode the
+ *object* which can either be a byte string or a character buffer using
+ the codec for *encoding*. The *encoding* parameter is a string giving
+ the name of an encoding; if the encoding is not known, :exc:`LookupError`
+ is raised. Error handling is done according to *errors*; this specifies the
+ treatment of characters which are invalid in the input encoding. If
+ *errors* is ``'strict'`` (the default), a :exc:`ValueError` is raised on
+ errors, while a value of ``'ignore'`` causes errors to be silently ignored,
+ and a value of ``'replace'`` causes the official Unicode replacement character,
+ U+FFFD, to be used to replace input characters which cannot be decoded.
+ See also the :mod:`codecs` module.
+
+ When only *object* is given, this returns its nicely printable representation.
+ For strings, this is the string itself. The difference with ``repr(object)``
+ is that ``str(object)`` does not always attempt to return a string that is
+ acceptable to :func:`eval`; its goal is to return a printable string.
+ With no arguments, this returns the empty string.
+
+ Objects can specify what ``str(object)`` returns by defining a :meth:`__str__`
+ special method.
+
+ For more information on strings see :ref:`typesseq` which describes sequence
+ functionality (strings are sequences), and also the string-specific methods
+ described in the :ref:`string-methods` section. To output formatted strings
+ use template strings or the ``%`` operator described in the
+ :ref:`string-formatting` section. In addition see the :ref:`stringservices`
+ section. See also :func:`unicode`.
+
+
+.. function:: sum(iterable[, start])
+
+ Sums *start* and the items of an *iterable* from left to right and returns the
+ total. *start* defaults to ``0``. The *iterable*'s items are normally numbers,
+ and are not allowed to be strings. The fast, correct way to concatenate a
+ sequence of strings is by calling ``''.join(sequence)``.
+
+ .. versionadded:: 2.3
+
+
+.. function:: super(type[, object-or-type])
+
+ Return the superclass of *type*. If the second argument is omitted the super
+ object returned is unbound. If the second argument is an object,
+ ``isinstance(obj, type)`` must be true. If the second argument is a type,
+ ``issubclass(type2, type)`` must be true. :func:`super` only works for new-style
+ classes.
+
+ A typical use for calling a cooperative superclass method is::
+
+ class C(B):
+ def meth(self, arg):
+ super(C, self).meth(arg)
+
+ Note that :func:`super` is implemented as part of the binding process for
+ explicit dotted attribute lookups such as ``super(C, self).__getitem__(name)``.
+ Accordingly, :func:`super` is undefined for implicit lookups using statements or
+ operators such as ``super(C, self)[name]``.
+
+ .. versionadded:: 2.2
+
+
+.. function:: tuple([iterable])
+
+ Return a tuple whose items are the same and in the same order as *iterable*'s
+ items. *iterable* may be a sequence, a container that supports iteration, or an
+ iterator object. If *iterable* is already a tuple, it is returned unchanged.
+ For instance, ``tuple('abc')`` returns ``('a', 'b', 'c')`` and ``tuple([1, 2,
+ 3])`` returns ``(1, 2, 3)``. If no argument is given, returns a new empty
+ tuple, ``()``.
+
+ :class:`tuple` is an immutable sequence type, as documented in
+ :ref:`typesseq`. For other containers see the built in :class:`dict`,
+ :class:`list`, and :class:`set` classes, and the :mod:`collections` module.
+
+
+.. function:: type(object)
+
+ .. index:: object: type
+
+ Return the type of an *object*. The return value is a type object. The
+ :func:`isinstance` built-in function is recommended for testing the type of an
+ object.
+
+ With three arguments, :func:`type` functions as a constructor as detailed below.
+
+
+.. function:: type(name, bases, dict)
+ :noindex:
+
+ Return a new type object. This is essentially a dynamic form of the
+ :keyword:`class` statement. The *name* string is the class name and becomes the
+ :attr:`__name__` attribute; the *bases* tuple itemizes the base classes and
+ becomes the :attr:`__bases__` attribute; and the *dict* dictionary is the
+ namespace containing definitions for class body and becomes the :attr:`__dict__`
+ attribute. For example, the following two statements create identical
+ :class:`type` objects::
+
+ >>> class X(object):
+ ... a = 1
+ ...
+ >>> X = type('X', (object,), dict(a=1))
+
+ .. versionadded:: 2.2
+
+
+.. function:: vars([object])
+
+ Without arguments, return a dictionary corresponding to the current local symbol
+ table. With a module, class or class instance object as argument (or anything
+ else that has a :attr:`__dict__` attribute), returns a dictionary corresponding
+ to the object's symbol table. The returned dictionary should not be modified:
+ the effects on the corresponding symbol table are undefined. [#]_
+
+
+.. function:: zip([iterable, ...])
+
+ This function returns a list of tuples, where the *i*-th tuple contains the
+ *i*-th element from each of the argument sequences or iterables. The returned
+ list is truncated in length to the length of the shortest argument sequence.
+ When there are multiple arguments which are all of the same length, :func:`zip`
+ is similar to :func:`map` with an initial argument of ``None``. With a single
+ sequence argument, it returns a list of 1-tuples. With no arguments, it returns
+ an empty list.
+
+ .. versionadded:: 2.0
+
+ .. versionchanged:: 2.4
+ Formerly, :func:`zip` required at least one argument and ``zip()`` raised a
+ :exc:`TypeError` instead of returning an empty list.
+
+.. % ---------------------------------------------------------------------------
+
+
+.. _non-essential-built-in-funcs:
+
+Non-essential Built-in Functions
+================================
+
+There are several built-in functions that are no longer essential to learn, know
+or use in modern Python programming. They have been kept here to maintain
+backwards compatibility with programs written for older versions of Python.
+
+Python programmers, trainers, students and bookwriters should feel free to
+bypass these functions without concerns about missing something important.
+
+
+.. function:: buffer(object[, offset[, size]])
+
+ The *object* argument must be an object that supports the buffer call interface
+ (such as strings, arrays, and buffers). A new buffer object will be created
+ which references the *object* argument. The buffer object will be a slice from
+ the beginning of *object* (or from the specified *offset*). The slice will
+ extend to the end of *object* (or will have a length given by the *size*
+ argument).
+
+
+
+.. rubric:: Footnotes
+
+.. [#] Specifying a buffer size currently has no effect on systems that don't have
+ :cfunc:`setvbuf`. The interface to specify the buffer size is not done using a
+ method that calls :cfunc:`setvbuf`, because that may dump core when called after
+ any I/O has been performed, and there's no reliable way to determine whether
+ this is the case.
+
+.. [#] In the current implementation, local variable bindings cannot normally be
+ affected this way, but variables retrieved from other scopes (such as modules)
+ can be. This may change.
+
diff --git a/Doc/library/functools.rst b/Doc/library/functools.rst
new file mode 100644
index 0000000000..4874b5569b
--- /dev/null
+++ b/Doc/library/functools.rst
@@ -0,0 +1,145 @@
+:mod:`functools` --- Higher order functions and operations on callable objects
+==============================================================================
+
+.. module:: functools
+ :synopsis: Higher order functions and operations on callable objects.
+.. moduleauthor:: Peter Harris <scav@blueyonder.co.uk>
+.. moduleauthor:: Raymond Hettinger <python@rcn.com>
+.. moduleauthor:: Nick Coghlan <ncoghlan@gmail.com>
+.. sectionauthor:: Peter Harris <scav@blueyonder.co.uk>
+
+
+.. versionadded:: 2.5
+
+The :mod:`functools` module is for higher-order functions: functions that act on
+or return other functions. In general, any callable object can be treated as a
+function for the purposes of this module.
+
+The :mod:`functools` module defines the following function:
+
+
+.. function:: partial(func[,*args][, **keywords])
+
+ Return a new :class:`partial` object which when called will behave like *func*
+ called with the positional arguments *args* and keyword arguments *keywords*. If
+ more arguments are supplied to the call, they are appended to *args*. If
+ additional keyword arguments are supplied, they extend and override *keywords*.
+ Roughly equivalent to::
+
+ def partial(func, *args, **keywords):
+ def newfunc(*fargs, **fkeywords):
+ newkeywords = keywords.copy()
+ newkeywords.update(fkeywords)
+ return func(*(args + fargs), **newkeywords)
+ newfunc.func = func
+ newfunc.args = args
+ newfunc.keywords = keywords
+ return newfunc
+
+ The :func:`partial` is used for partial function application which "freezes"
+ some portion of a function's arguments and/or keywords resulting in a new object
+ with a simplified signature. For example, :func:`partial` can be used to create
+ a callable that behaves like the :func:`int` function where the *base* argument
+ defaults to two::
+
+ >>> basetwo = partial(int, base=2)
+ >>> basetwo.__doc__ = 'Convert base 2 string to an int.'
+ >>> basetwo('10010')
+ 18
+
+
+.. function:: reduce(function, sequence[, initializer])
+
+ Apply *function* of two arguments cumulatively to the items of *sequence*, from
+ left to right, so as to reduce the sequence to a single value. For example,
+ ``reduce(lambda x, y: x+y, [1, 2, 3, 4, 5])`` calculates ``((((1+2)+3)+4)+5)``.
+ The left argument, *x*, is the accumulated value and the right argument, *y*, is
+ the update value from the *sequence*. If the optional *initializer* is present,
+ it is placed before the items of the sequence in the calculation, and serves as
+ a default when the sequence is empty. If *initializer* is not given and
+ *sequence* contains only one item, the first item is returned.
+
+
+.. function:: update_wrapper(wrapper, wrapped[, assigned][, updated])
+
+ Update a *wrapper* function to look like the *wrapped* function. The optional
+ arguments are tuples to specify which attributes of the original function are
+ assigned directly to the matching attributes on the wrapper function and which
+ attributes of the wrapper function are updated with the corresponding attributes
+ from the original function. The default values for these arguments are the
+ module level constants *WRAPPER_ASSIGNMENTS* (which assigns to the wrapper
+ function's *__name__*, *__module__* and *__doc__*, the documentation string) and
+ *WRAPPER_UPDATES* (which updates the wrapper function's *__dict__*, i.e. the
+ instance dictionary).
+
+ The main intended use for this function is in decorator functions which wrap the
+ decorated function and return the wrapper. If the wrapper function is not
+ updated, the metadata of the returned function will reflect the wrapper
+ definition rather than the original function definition, which is typically less
+ than helpful.
+
+
+.. function:: wraps(wrapped[, assigned][, updated])
+
+ This is a convenience function for invoking ``partial(update_wrapper,
+ wrapped=wrapped, assigned=assigned, updated=updated)`` as a function decorator
+ when defining a wrapper function. For example::
+
+ >>> def my_decorator(f):
+ ... @wraps(f)
+ ... def wrapper(*args, **kwds):
+ ... print 'Calling decorated function'
+ ... return f(*args, **kwds)
+ ... return wrapper
+ ...
+ >>> @my_decorator
+ ... def example():
+ ... """Docstring"""
+ ... print 'Called example function'
+ ...
+ >>> example()
+ Calling decorated function
+ Called example function
+ >>> example.__name__
+ 'example'
+ >>> example.__doc__
+ 'Docstring'
+
+ Without the use of this decorator factory, the name of the example function
+ would have been ``'wrapper'``, and the docstring of the original :func:`example`
+ would have been lost.
+
+
+.. _partial-objects:
+
+:class:`partial` Objects
+------------------------
+
+:class:`partial` objects are callable objects created by :func:`partial`. They
+have three read-only attributes:
+
+
+.. attribute:: partial.func
+
+ A callable object or function. Calls to the :class:`partial` object will be
+ forwarded to :attr:`func` with new arguments and keywords.
+
+
+.. attribute:: partial.args
+
+ The leftmost positional arguments that will be prepended to the positional
+ arguments provided to a :class:`partial` object call.
+
+
+.. attribute:: partial.keywords
+
+ The keyword arguments that will be supplied when the :class:`partial` object is
+ called.
+
+:class:`partial` objects are like :class:`function` objects in that they are
+callable, weak referencable, and can have attributes. There are some important
+differences. For instance, the :attr:`__name__` and :attr:`__doc__` attributes
+are not created automatically. Also, :class:`partial` objects defined in
+classes behave like static methods and do not transform into bound methods
+during instance attribute look-up.
+
diff --git a/Doc/library/gc.rst b/Doc/library/gc.rst
new file mode 100644
index 0000000000..70e4a6bae2
--- /dev/null
+++ b/Doc/library/gc.rst
@@ -0,0 +1,211 @@
+
+:mod:`gc` --- Garbage Collector interface
+=========================================
+
+.. module:: gc
+ :synopsis: Interface to the cycle-detecting garbage collector.
+.. moduleauthor:: Neil Schemenauer <nas@arctrix.com>
+.. sectionauthor:: Neil Schemenauer <nas@arctrix.com>
+
+
+This module provides an interface to the optional garbage collector. It
+provides the ability to disable the collector, tune the collection frequency,
+and set debugging options. It also provides access to unreachable objects that
+the collector found but cannot free. Since the collector supplements the
+reference counting already used in Python, you can disable the collector if you
+are sure your program does not create reference cycles. Automatic collection
+can be disabled by calling ``gc.disable()``. To debug a leaking program call
+``gc.set_debug(gc.DEBUG_LEAK)``. Notice that this includes
+``gc.DEBUG_SAVEALL``, causing garbage-collected objects to be saved in
+gc.garbage for inspection.
+
+The :mod:`gc` module provides the following functions:
+
+
+.. function:: enable()
+
+ Enable automatic garbage collection.
+
+
+.. function:: disable()
+
+ Disable automatic garbage collection.
+
+
+.. function:: isenabled()
+
+ Returns true if automatic collection is enabled.
+
+
+.. function:: collect([generation])
+
+ With no arguments, run a full collection. The optional argument *generation*
+ may be an integer specifying which generation to collect (from 0 to 2). A
+ :exc:`ValueError` is raised if the generation number is invalid. The number of
+ unreachable objects found is returned.
+
+ .. versionchanged:: 2.5
+ The optional *generation* argument was added.
+
+
+.. function:: set_debug(flags)
+
+ Set the garbage collection debugging flags. Debugging information will be
+ written to ``sys.stderr``. See below for a list of debugging flags which can be
+ combined using bit operations to control debugging.
+
+
+.. function:: get_debug()
+
+ Return the debugging flags currently set.
+
+
+.. function:: get_objects()
+
+ Returns a list of all objects tracked by the collector, excluding the list
+ returned.
+
+ .. versionadded:: 2.2
+
+
+.. function:: set_threshold(threshold0[, threshold1[, threshold2]])
+
+ Set the garbage collection thresholds (the collection frequency). Setting
+ *threshold0* to zero disables collection.
+
+ The GC classifies objects into three generations depending on how many
+ collection sweeps they have survived. New objects are placed in the youngest
+ generation (generation ``0``). If an object survives a collection it is moved
+ into the next older generation. Since generation ``2`` is the oldest
+ generation, objects in that generation remain there after a collection. In
+ order to decide when to run, the collector keeps track of the number object
+ allocations and deallocations since the last collection. When the number of
+ allocations minus the number of deallocations exceeds *threshold0*, collection
+ starts. Initially only generation ``0`` is examined. If generation ``0`` has
+ been examined more than *threshold1* times since generation ``1`` has been
+ examined, then generation ``1`` is examined as well. Similarly, *threshold2*
+ controls the number of collections of generation ``1`` before collecting
+ generation ``2``.
+
+
+.. function:: get_count()
+
+ Return the current collection counts as a tuple of ``(count0, count1,
+ count2)``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: get_threshold()
+
+ Return the current collection thresholds as a tuple of ``(threshold0,
+ threshold1, threshold2)``.
+
+
+.. function:: get_referrers(*objs)
+
+ Return the list of objects that directly refer to any of objs. This function
+ will only locate those containers which support garbage collection; extension
+ types which do refer to other objects but do not support garbage collection will
+ not be found.
+
+ Note that objects which have already been dereferenced, but which live in cycles
+ and have not yet been collected by the garbage collector can be listed among the
+ resulting referrers. To get only currently live objects, call :func:`collect`
+ before calling :func:`get_referrers`.
+
+ Care must be taken when using objects returned by :func:`get_referrers` because
+ some of them could still be under construction and hence in a temporarily
+ invalid state. Avoid using :func:`get_referrers` for any purpose other than
+ debugging.
+
+ .. versionadded:: 2.2
+
+
+.. function:: get_referents(*objs)
+
+ Return a list of objects directly referred to by any of the arguments. The
+ referents returned are those objects visited by the arguments' C-level
+ :attr:`tp_traverse` methods (if any), and may not be all objects actually
+ directly reachable. :attr:`tp_traverse` methods are supported only by objects
+ that support garbage collection, and are only required to visit objects that may
+ be involved in a cycle. So, for example, if an integer is directly reachable
+ from an argument, that integer object may or may not appear in the result list.
+
+ .. versionadded:: 2.3
+
+The following variable is provided for read-only access (you can mutate its
+value but should not rebind it):
+
+
+.. data:: garbage
+
+ A list of objects which the collector found to be unreachable but could not be
+ freed (uncollectable objects). By default, this list contains only objects with
+ :meth:`__del__` methods. [#]_ Objects that have :meth:`__del__` methods and are
+ part of a reference cycle cause the entire reference cycle to be uncollectable,
+ including objects not necessarily in the cycle but reachable only from it.
+ Python doesn't collect such cycles automatically because, in general, it isn't
+ possible for Python to guess a safe order in which to run the :meth:`__del__`
+ methods. If you know a safe order, you can force the issue by examining the
+ *garbage* list, and explicitly breaking cycles due to your objects within the
+ list. Note that these objects are kept alive even so by virtue of being in the
+ *garbage* list, so they should be removed from *garbage* too. For example,
+ after breaking cycles, do ``del gc.garbage[:]`` to empty the list. It's
+ generally better to avoid the issue by not creating cycles containing objects
+ with :meth:`__del__` methods, and *garbage* can be examined in that case to
+ verify that no such cycles are being created.
+
+ If :const:`DEBUG_SAVEALL` is set, then all unreachable objects will be added to
+ this list rather than freed.
+
+The following constants are provided for use with :func:`set_debug`:
+
+
+.. data:: DEBUG_STATS
+
+ Print statistics during collection. This information can be useful when tuning
+ the collection frequency.
+
+
+.. data:: DEBUG_COLLECTABLE
+
+ Print information on collectable objects found.
+
+
+.. data:: DEBUG_UNCOLLECTABLE
+
+ Print information of uncollectable objects found (objects which are not
+ reachable but cannot be freed by the collector). These objects will be added to
+ the ``garbage`` list.
+
+
+.. data:: DEBUG_INSTANCES
+
+ When :const:`DEBUG_COLLECTABLE` or :const:`DEBUG_UNCOLLECTABLE` is set, print
+ information about instance objects found.
+
+
+.. data:: DEBUG_OBJECTS
+
+ When :const:`DEBUG_COLLECTABLE` or :const:`DEBUG_UNCOLLECTABLE` is set, print
+ information about objects other than instance objects found.
+
+
+.. data:: DEBUG_SAVEALL
+
+ When set, all unreachable objects found will be appended to *garbage* rather
+ than being freed. This can be useful for debugging a leaking program.
+
+
+.. data:: DEBUG_LEAK
+
+ The debugging flags necessary for the collector to print information about a
+ leaking program (equal to ``DEBUG_COLLECTABLE | DEBUG_UNCOLLECTABLE |
+ DEBUG_INSTANCES | DEBUG_OBJECTS | DEBUG_SAVEALL``).
+
+.. rubric:: Footnotes
+
+.. [#] Prior to Python 2.2, the list contained all instance objects in unreachable
+ cycles, not only those with :meth:`__del__` methods.
+
diff --git a/Doc/library/gdbm.rst b/Doc/library/gdbm.rst
new file mode 100644
index 0000000000..ce27f6c645
--- /dev/null
+++ b/Doc/library/gdbm.rst
@@ -0,0 +1,122 @@
+
+:mod:`gdbm` --- GNU's reinterpretation of dbm
+=============================================
+
+.. module:: gdbm
+ :platform: Unix
+ :synopsis: GNU's reinterpretation of dbm.
+
+
+.. index:: module: dbm
+
+This module is quite similar to the :mod:`dbm` module, but uses ``gdbm`` instead
+to provide some additional functionality. Please note that the file formats
+created by ``gdbm`` and ``dbm`` are incompatible.
+
+The :mod:`gdbm` module provides an interface to the GNU DBM library. ``gdbm``
+objects behave like mappings (dictionaries), except that keys and values are
+always strings. Printing a ``gdbm`` object doesn't print the keys and values,
+and the :meth:`items` and :meth:`values` methods are not supported.
+
+The module defines the following constant and functions:
+
+
+.. exception:: error
+
+ Raised on ``gdbm``\ -specific errors, such as I/O errors. :exc:`KeyError` is
+ raised for general mapping errors like specifying an incorrect key.
+
+
+.. function:: open(filename, [flag, [mode]])
+
+ Open a ``gdbm`` database and return a ``gdbm`` object. The *filename* argument
+ is the name of the database file.
+
+ The optional *flag* argument can be:
+
+ +---------+-------------------------------------------+
+ | Value | Meaning |
+ +=========+===========================================+
+ | ``'r'`` | Open existing database for reading only |
+ | | (default) |
+ +---------+-------------------------------------------+
+ | ``'w'`` | Open existing database for reading and |
+ | | writing |
+ +---------+-------------------------------------------+
+ | ``'c'`` | Open database for reading and writing, |
+ | | creating it if it doesn't exist |
+ +---------+-------------------------------------------+
+ | ``'n'`` | Always create a new, empty database, open |
+ | | for reading and writing |
+ +---------+-------------------------------------------+
+
+ The following additional characters may be appended to the flag to control
+ how the database is opened:
+
+ +---------+--------------------------------------------+
+ | Value | Meaning |
+ +=========+============================================+
+ | ``'f'`` | Open the database in fast mode. Writes |
+ | | to the database will not be synchronized. |
+ +---------+--------------------------------------------+
+ | ``'s'`` | Synchronized mode. This will cause changes |
+ | | to the database to be immediately written |
+ | | to the file. |
+ +---------+--------------------------------------------+
+ | ``'u'`` | Do not lock database. |
+ +---------+--------------------------------------------+
+
+ Not all flags are valid for all versions of ``gdbm``. The module constant
+ :const:`open_flags` is a string of supported flag characters. The exception
+ :exc:`error` is raised if an invalid flag is specified.
+
+ The optional *mode* argument is the Unix mode of the file, used only when the
+ database has to be created. It defaults to octal ``0666``.
+
+In addition to the dictionary-like methods, ``gdbm`` objects have the following
+methods:
+
+
+.. function:: firstkey()
+
+ It's possible to loop over every key in the database using this method and the
+ :meth:`nextkey` method. The traversal is ordered by ``gdbm``'s internal hash
+ values, and won't be sorted by the key values. This method returns the starting
+ key.
+
+
+.. function:: nextkey(key)
+
+ Returns the key that follows *key* in the traversal. The following code prints
+ every key in the database ``db``, without having to create a list in memory that
+ contains them all::
+
+ k = db.firstkey()
+ while k != None:
+ print k
+ k = db.nextkey(k)
+
+
+.. function:: reorganize()
+
+ If you have carried out a lot of deletions and would like to shrink the space
+ used by the ``gdbm`` file, this routine will reorganize the database. ``gdbm``
+ will not shorten the length of a database file except by using this
+ reorganization; otherwise, deleted file space will be kept and reused as new
+ (key, value) pairs are added.
+
+
+.. function:: sync()
+
+ When the database has been opened in fast mode, this method forces any
+ unwritten data to be written to the disk.
+
+
+.. seealso::
+
+ Module :mod:`anydbm`
+ Generic interface to ``dbm``\ -style databases.
+
+ Module :mod:`whichdb`
+ Utility module used to determine the type of an existing database.
+
diff --git a/Doc/library/gensuitemodule.rst b/Doc/library/gensuitemodule.rst
new file mode 100644
index 0000000000..3fc52542f5
--- /dev/null
+++ b/Doc/library/gensuitemodule.rst
@@ -0,0 +1,63 @@
+
+:mod:`gensuitemodule` --- Generate OSA stub packages
+====================================================
+
+.. module:: gensuitemodule
+ :platform: Mac
+ :synopsis: Create a stub package from an OSA dictionary
+.. sectionauthor:: Jack Jansen <Jack.Jansen@cwi.nl>
+
+
+.. % \moduleauthor{Jack Jansen?}{email}
+
+The :mod:`gensuitemodule` module creates a Python package implementing stub code
+for the AppleScript suites that are implemented by a specific application,
+according to its AppleScript dictionary.
+
+It is usually invoked by the user through the :program:`PythonIDE`, but it can
+also be run as a script from the command line (pass :option:`--help` for help on
+the options) or imported from Python code. For an example of its use see
+:file:`Mac/scripts/genallsuites.py` in a source distribution, which generates
+the stub packages that are included in the standard library.
+
+It defines the following public functions:
+
+
+.. function:: is_scriptable(application)
+
+ Returns true if ``application``, which should be passed as a pathname, appears
+ to be scriptable. Take the return value with a grain of salt: :program:`Internet
+ Explorer` appears not to be scriptable but definitely is.
+
+
+.. function:: processfile(application[, output, basepkgname, edit_modnames, creatorsignature, dump, verbose])
+
+ Create a stub package for ``application``, which should be passed as a full
+ pathname. For a :file:`.app` bundle this is the pathname to the bundle, not to
+ the executable inside the bundle; for an unbundled CFM application you pass the
+ filename of the application binary.
+
+ This function asks the application for its OSA terminology resources, decodes
+ these resources and uses the resultant data to create the Python code for the
+ package implementing the client stubs.
+
+ ``output`` is the pathname where the resulting package is stored, if not
+ specified a standard "save file as" dialog is presented to the user.
+ ``basepkgname`` is the base package on which this package will build, and
+ defaults to :mod:`StdSuites`. Only when generating :mod:`StdSuites` itself do
+ you need to specify this. ``edit_modnames`` is a dictionary that can be used to
+ change modulenames that are too ugly after name mangling. ``creator_signature``
+ can be used to override the 4-char creator code, which is normally obtained from
+ the :file:`PkgInfo` file in the package or from the CFM file creator signature.
+ When ``dump`` is given it should refer to a file object, and ``processfile``
+ will stop after decoding the resources and dump the Python representation of the
+ terminology resources to this file. ``verbose`` should also be a file object,
+ and specifying it will cause ``processfile`` to tell you what it is doing.
+
+
+.. function:: processfile_fromresource(application[, output, basepkgname, edit_modnames, creatorsignature, dump, verbose])
+
+ This function does the same as ``processfile``, except that it uses a different
+ method to get the terminology resources. It opens ``application`` as a resource
+ file and reads all ``"aete"`` and ``"aeut"`` resources from this file.
+
diff --git a/Doc/library/getopt.rst b/Doc/library/getopt.rst
new file mode 100644
index 0000000000..0d9641dd04
--- /dev/null
+++ b/Doc/library/getopt.rst
@@ -0,0 +1,147 @@
+
+:mod:`getopt` --- Parser for command line options
+=================================================
+
+.. module:: getopt
+ :synopsis: Portable parser for command line options; support both short and long option
+ names.
+
+
+This module helps scripts to parse the command line arguments in ``sys.argv``.
+It supports the same conventions as the Unix :cfunc:`getopt` function (including
+the special meanings of arguments of the form '``-``' and '``-``\ ``-``'). Long
+options similar to those supported by GNU software may be used as well via an
+optional third argument. This module provides a single function and an
+exception:
+
+.. % That's to fool latex2html into leaving the two hyphens alone!
+
+
+.. function:: getopt(args, options[, long_options])
+
+ Parses command line options and parameter list. *args* is the argument list to
+ be parsed, without the leading reference to the running program. Typically, this
+ means ``sys.argv[1:]``. *options* is the string of option letters that the
+ script wants to recognize, with options that require an argument followed by a
+ colon (``':'``; i.e., the same format that Unix :cfunc:`getopt` uses).
+
+ .. note::
+
+ Unlike GNU :cfunc:`getopt`, after a non-option argument, all further arguments
+ are considered also non-options. This is similar to the way non-GNU Unix systems
+ work.
+
+ *long_options*, if specified, must be a list of strings with the names of the
+ long options which should be supported. The leading ``'-``\ ``-'`` characters
+ should not be included in the option name. Long options which require an
+ argument should be followed by an equal sign (``'='``). To accept only long
+ options, *options* should be an empty string. Long options on the command line
+ can be recognized so long as they provide a prefix of the option name that
+ matches exactly one of the accepted options. For example, if *long_options* is
+ ``['foo', 'frob']``, the option :option:`--fo` will match as :option:`--foo`,
+ but :option:`--f` will not match uniquely, so :exc:`GetoptError` will be raised.
+
+ The return value consists of two elements: the first is a list of ``(option,
+ value)`` pairs; the second is the list of program arguments left after the
+ option list was stripped (this is a trailing slice of *args*). Each
+ option-and-value pair returned has the option as its first element, prefixed
+ with a hyphen for short options (e.g., ``'-x'``) or two hyphens for long
+ options (e.g., ``'-``\ ``-long-option'``), and the option argument as its
+ second element, or an empty string if the option has no argument. The
+ options occur in the list in the same order in which they were found, thus
+ allowing multiple occurrences. Long and short options may be mixed.
+
+
+.. function:: gnu_getopt(args, options[, long_options])
+
+ This function works like :func:`getopt`, except that GNU style scanning mode is
+ used by default. This means that option and non-option arguments may be
+ intermixed. The :func:`getopt` function stops processing options as soon as a
+ non-option argument is encountered.
+
+ If the first character of the option string is '+', or if the environment
+ variable POSIXLY_CORRECT is set, then option processing stops as soon as a
+ non-option argument is encountered.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: GetoptError
+
+ This is raised when an unrecognized option is found in the argument list or when
+ an option requiring an argument is given none. The argument to the exception is
+ a string indicating the cause of the error. For long options, an argument given
+ to an option which does not require one will also cause this exception to be
+ raised. The attributes :attr:`msg` and :attr:`opt` give the error message and
+ related option; if there is no specific option to which the exception relates,
+ :attr:`opt` is an empty string.
+
+ .. versionchanged:: 1.6
+ Introduced :exc:`GetoptError` as a synonym for :exc:`error`.
+
+
+.. exception:: error
+
+ Alias for :exc:`GetoptError`; for backward compatibility.
+
+An example using only Unix style options::
+
+ >>> import getopt
+ >>> args = '-a -b -cfoo -d bar a1 a2'.split()
+ >>> args
+ ['-a', '-b', '-cfoo', '-d', 'bar', 'a1', 'a2']
+ >>> optlist, args = getopt.getopt(args, 'abc:d:')
+ >>> optlist
+ [('-a', ''), ('-b', ''), ('-c', 'foo'), ('-d', 'bar')]
+ >>> args
+ ['a1', 'a2']
+
+Using long option names is equally easy::
+
+ >>> s = '--condition=foo --testing --output-file abc.def -x a1 a2'
+ >>> args = s.split()
+ >>> args
+ ['--condition=foo', '--testing', '--output-file', 'abc.def', '-x', 'a1', 'a2']
+ >>> optlist, args = getopt.getopt(args, 'x', [
+ ... 'condition=', 'output-file=', 'testing'])
+ >>> optlist
+ [('--condition', 'foo'), ('--testing', ''), ('--output-file', 'abc.def'), ('-x',
+ '')]
+ >>> args
+ ['a1', 'a2']
+
+In a script, typical usage is something like this::
+
+ import getopt, sys
+
+ def main():
+ try:
+ opts, args = getopt.getopt(sys.argv[1:], "ho:v", ["help", "output="])
+ except getopt.GetoptError as err:
+ # print help information and exit:
+ print str(err) # will print something like "option -a not recognized"
+ usage()
+ sys.exit(2)
+ output = None
+ verbose = False
+ for o, a in opts:
+ if o == "-v":
+ verbose = True
+ elif o in ("-h", "--help"):
+ usage()
+ sys.exit()
+ elif o in ("-o", "--output"):
+ output = a
+ else:
+ assert False, "unhandled option"
+ # ...
+
+ if __name__ == "__main__":
+ main()
+
+
+.. seealso::
+
+ Module :mod:`optparse`
+ More object-oriented command line option parsing.
+
diff --git a/Doc/library/getpass.rst b/Doc/library/getpass.rst
new file mode 100644
index 0000000000..45c6e53b5f
--- /dev/null
+++ b/Doc/library/getpass.rst
@@ -0,0 +1,38 @@
+
+:mod:`getpass` --- Portable password input
+==========================================
+
+.. module:: getpass
+ :synopsis: Portable reading of passwords and retrieval of the userid.
+.. moduleauthor:: Piers Lauder <piers@cs.su.oz.au>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. % Windows (& Mac?) support by Guido van Rossum.
+
+The :mod:`getpass` module provides two functions:
+
+
+.. function:: getpass([prompt[, stream]])
+
+ Prompt the user for a password without echoing. The user is prompted using the
+ string *prompt*, which defaults to ``'Password: '``. On Unix, the prompt is
+ written to the file-like object *stream*, which defaults to ``sys.stdout`` (this
+ argument is ignored on Windows).
+
+ Availability: Macintosh, Unix, Windows.
+
+ .. versionchanged:: 2.5
+ The *stream* parameter was added.
+
+
+.. function:: getuser()
+
+ Return the "login name" of the user. Availability: Unix, Windows.
+
+ This function checks the environment variables :envvar:`LOGNAME`,
+ :envvar:`USER`, :envvar:`LNAME` and :envvar:`USERNAME`, in order, and returns
+ the value of the first one which is set to a non-empty string. If none are set,
+ the login name from the password database is returned on systems which support
+ the :mod:`pwd` module, otherwise, an exception is raised.
+
diff --git a/Doc/library/gettext.rst b/Doc/library/gettext.rst
new file mode 100644
index 0000000000..51628e69ba
--- /dev/null
+++ b/Doc/library/gettext.rst
@@ -0,0 +1,765 @@
+
+:mod:`gettext` --- Multilingual internationalization services
+=============================================================
+
+.. module:: gettext
+ :synopsis: Multilingual internationalization services.
+.. moduleauthor:: Barry A. Warsaw <barry@zope.com>
+.. sectionauthor:: Barry A. Warsaw <barry@zope.com>
+
+
+The :mod:`gettext` module provides internationalization (I18N) and localization
+(L10N) services for your Python modules and applications. It supports both the
+GNU ``gettext`` message catalog API and a higher level, class-based API that may
+be more appropriate for Python files. The interface described below allows you
+to write your module and application messages in one natural language, and
+provide a catalog of translated messages for running under different natural
+languages.
+
+Some hints on localizing your Python modules and applications are also given.
+
+
+GNU :program:`gettext` API
+--------------------------
+
+The :mod:`gettext` module defines the following API, which is very similar to
+the GNU :program:`gettext` API. If you use this API you will affect the
+translation of your entire application globally. Often this is what you want if
+your application is monolingual, with the choice of language dependent on the
+locale of your user. If you are localizing a Python module, or if your
+application needs to switch languages on the fly, you probably want to use the
+class-based API instead.
+
+
+.. function:: bindtextdomain(domain[, localedir])
+
+ Bind the *domain* to the locale directory *localedir*. More concretely,
+ :mod:`gettext` will look for binary :file:`.mo` files for the given domain using
+ the path (on Unix): :file:`localedir/language/LC_MESSAGES/domain.mo`, where
+ *languages* is searched for in the environment variables :envvar:`LANGUAGE`,
+ :envvar:`LC_ALL`, :envvar:`LC_MESSAGES`, and :envvar:`LANG` respectively.
+
+ If *localedir* is omitted or ``None``, then the current binding for *domain* is
+ returned. [#]_
+
+
+.. function:: bind_textdomain_codeset(domain[, codeset])
+
+ Bind the *domain* to *codeset*, changing the encoding of strings returned by the
+ :func:`gettext` family of functions. If *codeset* is omitted, then the current
+ binding is returned.
+
+ .. versionadded:: 2.4
+
+
+.. function:: textdomain([domain])
+
+ Change or query the current global domain. If *domain* is ``None``, then the
+ current global domain is returned, otherwise the global domain is set to
+ *domain*, which is returned.
+
+
+.. function:: gettext(message)
+
+ Return the localized translation of *message*, based on the current global
+ domain, language, and locale directory. This function is usually aliased as
+ :func:`_` in the local namespace (see examples below).
+
+
+.. function:: lgettext(message)
+
+ Equivalent to :func:`gettext`, but the translation is returned in the preferred
+ system encoding, if no other encoding was explicitly set with
+ :func:`bind_textdomain_codeset`.
+
+ .. versionadded:: 2.4
+
+
+.. function:: dgettext(domain, message)
+
+ Like :func:`gettext`, but look the message up in the specified *domain*.
+
+
+.. function:: ldgettext(domain, message)
+
+ Equivalent to :func:`dgettext`, but the translation is returned in the preferred
+ system encoding, if no other encoding was explicitly set with
+ :func:`bind_textdomain_codeset`.
+
+ .. versionadded:: 2.4
+
+
+.. function:: ngettext(singular, plural, n)
+
+ Like :func:`gettext`, but consider plural forms. If a translation is found,
+ apply the plural formula to *n*, and return the resulting message (some
+ languages have more than two plural forms). If no translation is found, return
+ *singular* if *n* is 1; return *plural* otherwise.
+
+ The Plural formula is taken from the catalog header. It is a C or Python
+ expression that has a free variable *n*; the expression evaluates to the index
+ of the plural in the catalog. See the GNU gettext documentation for the precise
+ syntax to be used in :file:`.po` files and the formulas for a variety of
+ languages.
+
+ .. versionadded:: 2.3
+
+
+.. function:: lngettext(singular, plural, n)
+
+ Equivalent to :func:`ngettext`, but the translation is returned in the preferred
+ system encoding, if no other encoding was explicitly set with
+ :func:`bind_textdomain_codeset`.
+
+ .. versionadded:: 2.4
+
+
+.. function:: dngettext(domain, singular, plural, n)
+
+ Like :func:`ngettext`, but look the message up in the specified *domain*.
+
+ .. versionadded:: 2.3
+
+
+.. function:: ldngettext(domain, singular, plural, n)
+
+ Equivalent to :func:`dngettext`, but the translation is returned in the
+ preferred system encoding, if no other encoding was explicitly set with
+ :func:`bind_textdomain_codeset`.
+
+ .. versionadded:: 2.4
+
+Note that GNU :program:`gettext` also defines a :func:`dcgettext` method, but
+this was deemed not useful and so it is currently unimplemented.
+
+Here's an example of typical usage for this API::
+
+ import gettext
+ gettext.bindtextdomain('myapplication', '/path/to/my/language/directory')
+ gettext.textdomain('myapplication')
+ _ = gettext.gettext
+ # ...
+ print _('This is a translatable string.')
+
+
+Class-based API
+---------------
+
+The class-based API of the :mod:`gettext` module gives you more flexibility and
+greater convenience than the GNU :program:`gettext` API. It is the recommended
+way of localizing your Python applications and modules. :mod:`gettext` defines
+a "translations" class which implements the parsing of GNU :file:`.mo` format
+files, and has methods for returning either standard 8-bit strings or Unicode
+strings. Instances of this "translations" class can also install themselves in
+the built-in namespace as the function :func:`_`.
+
+
+.. function:: find(domain[, localedir[, languages[, all]]])
+
+ This function implements the standard :file:`.mo` file search algorithm. It
+ takes a *domain*, identical to what :func:`textdomain` takes. Optional
+ *localedir* is as in :func:`bindtextdomain` Optional *languages* is a list of
+ strings, where each string is a language code.
+
+ If *localedir* is not given, then the default system locale directory is used.
+ [#]_ If *languages* is not given, then the following environment variables are
+ searched: :envvar:`LANGUAGE`, :envvar:`LC_ALL`, :envvar:`LC_MESSAGES`, and
+ :envvar:`LANG`. The first one returning a non-empty value is used for the
+ *languages* variable. The environment variables should contain a colon separated
+ list of languages, which will be split on the colon to produce the expected list
+ of language code strings.
+
+ :func:`find` then expands and normalizes the languages, and then iterates
+ through them, searching for an existing file built of these components:
+
+ :file:`localedir/language/LC_MESSAGES/domain.mo`
+
+ The first such file name that exists is returned by :func:`find`. If no such
+ file is found, then ``None`` is returned. If *all* is given, it returns a list
+ of all file names, in the order in which they appear in the languages list or
+ the environment variables.
+
+
+.. function:: translation(domain[, localedir[, languages[, class_[, fallback[, codeset]]]]])
+
+ Return a :class:`Translations` instance based on the *domain*, *localedir*, and
+ *languages*, which are first passed to :func:`find` to get a list of the
+ associated :file:`.mo` file paths. Instances with identical :file:`.mo` file
+ names are cached. The actual class instantiated is either *class_* if provided,
+ otherwise :class:`GNUTranslations`. The class's constructor must take a single
+ file object argument. If provided, *codeset* will change the charset used to
+ encode translated strings.
+
+ If multiple files are found, later files are used as fallbacks for earlier ones.
+ To allow setting the fallback, :func:`copy.copy` is used to clone each
+ translation object from the cache; the actual instance data is still shared with
+ the cache.
+
+ If no :file:`.mo` file is found, this function raises :exc:`IOError` if
+ *fallback* is false (which is the default), and returns a
+ :class:`NullTranslations` instance if *fallback* is true.
+
+ .. versionchanged:: 2.4
+ Added the *codeset* parameter.
+
+
+.. function:: install(domain[, localedir[, unicode [, codeset[, names]]]])
+
+ This installs the function :func:`_` in Python's builtin namespace, based on
+ *domain*, *localedir*, and *codeset* which are passed to the function
+ :func:`translation`. The *unicode* flag is passed to the resulting translation
+ object's :meth:`install` method.
+
+ For the *names* parameter, please see the description of the translation
+ object's :meth:`install` method.
+
+ As seen below, you usually mark the strings in your application that are
+ candidates for translation, by wrapping them in a call to the :func:`_`
+ function, like this::
+
+ print _('This string will be translated.')
+
+ For convenience, you want the :func:`_` function to be installed in Python's
+ builtin namespace, so it is easily accessible in all modules of your
+ application.
+
+ .. versionchanged:: 2.4
+ Added the *codeset* parameter.
+
+ .. versionchanged:: 2.5
+ Added the *names* parameter.
+
+
+The :class:`NullTranslations` class
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Translation classes are what actually implement the translation of original
+source file message strings to translated message strings. The base class used
+by all translation classes is :class:`NullTranslations`; this provides the basic
+interface you can use to write your own specialized translation classes. Here
+are the methods of :class:`NullTranslations`:
+
+
+.. method:: NullTranslations.__init__([fp])
+
+ Takes an optional file object *fp*, which is ignored by the base class.
+ Initializes "protected" instance variables *_info* and *_charset* which are set
+ by derived classes, as well as *_fallback*, which is set through
+ :meth:`add_fallback`. It then calls ``self._parse(fp)`` if *fp* is not
+ ``None``.
+
+
+.. method:: NullTranslations._parse(fp)
+
+ No-op'd in the base class, this method takes file object *fp*, and reads the
+ data from the file, initializing its message catalog. If you have an
+ unsupported message catalog file format, you should override this method to
+ parse your format.
+
+
+.. method:: NullTranslations.add_fallback(fallback)
+
+ Add *fallback* as the fallback object for the current translation object. A
+ translation object should consult the fallback if it cannot provide a
+ translation for a given message.
+
+
+.. method:: NullTranslations.gettext(message)
+
+ If a fallback has been set, forward :meth:`gettext` to the fallback. Otherwise,
+ return the translated message. Overridden in derived classes.
+
+
+.. method:: NullTranslations.lgettext(message)
+
+ If a fallback has been set, forward :meth:`lgettext` to the fallback. Otherwise,
+ return the translated message. Overridden in derived classes.
+
+ .. versionadded:: 2.4
+
+
+.. method:: NullTranslations.ugettext(message)
+
+ If a fallback has been set, forward :meth:`ugettext` to the fallback. Otherwise,
+ return the translated message as a Unicode string. Overridden in derived
+ classes.
+
+
+.. method:: NullTranslations.ngettext(singular, plural, n)
+
+ If a fallback has been set, forward :meth:`ngettext` to the fallback. Otherwise,
+ return the translated message. Overridden in derived classes.
+
+ .. versionadded:: 2.3
+
+
+.. method:: NullTranslations.lngettext(singular, plural, n)
+
+ If a fallback has been set, forward :meth:`ngettext` to the fallback. Otherwise,
+ return the translated message. Overridden in derived classes.
+
+ .. versionadded:: 2.4
+
+
+.. method:: NullTranslations.ungettext(singular, plural, n)
+
+ If a fallback has been set, forward :meth:`ungettext` to the fallback.
+ Otherwise, return the translated message as a Unicode string. Overridden in
+ derived classes.
+
+ .. versionadded:: 2.3
+
+
+.. method:: NullTranslations.info()
+
+ Return the "protected" :attr:`_info` variable.
+
+
+.. method:: NullTranslations.charset()
+
+ Return the "protected" :attr:`_charset` variable.
+
+
+.. method:: NullTranslations.output_charset()
+
+ Return the "protected" :attr:`_output_charset` variable, which defines the
+ encoding used to return translated messages.
+
+ .. versionadded:: 2.4
+
+
+.. method:: NullTranslations.set_output_charset(charset)
+
+ Change the "protected" :attr:`_output_charset` variable, which defines the
+ encoding used to return translated messages.
+
+ .. versionadded:: 2.4
+
+
+.. method:: NullTranslations.install([unicode [, names]])
+
+ If the *unicode* flag is false, this method installs :meth:`self.gettext` into
+ the built-in namespace, binding it to ``_``. If *unicode* is true, it binds
+ :meth:`self.ugettext` instead. By default, *unicode* is false.
+
+ If the *names* parameter is given, it must be a sequence containing the names of
+ functions you want to install in the builtin namespace in addition to :func:`_`.
+ Supported names are ``'gettext'`` (bound to :meth:`self.gettext` or
+ :meth:`self.ugettext` according to the *unicode* flag), ``'ngettext'`` (bound to
+ :meth:`self.ngettext` or :meth:`self.ungettext` according to the *unicode*
+ flag), ``'lgettext'`` and ``'lngettext'``.
+
+ Note that this is only one way, albeit the most convenient way, to make the
+ :func:`_` function available to your application. Because it affects the entire
+ application globally, and specifically the built-in namespace, localized modules
+ should never install :func:`_`. Instead, they should use this code to make
+ :func:`_` available to their module::
+
+ import gettext
+ t = gettext.translation('mymodule', ...)
+ _ = t.gettext
+
+ This puts :func:`_` only in the module's global namespace and so only affects
+ calls within this module.
+
+ .. versionchanged:: 2.5
+ Added the *names* parameter.
+
+
+The :class:`GNUTranslations` class
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The :mod:`gettext` module provides one additional class derived from
+:class:`NullTranslations`: :class:`GNUTranslations`. This class overrides
+:meth:`_parse` to enable reading GNU :program:`gettext` format :file:`.mo` files
+in both big-endian and little-endian format. It also coerces both message ids
+and message strings to Unicode.
+
+:class:`GNUTranslations` parses optional meta-data out of the translation
+catalog. It is convention with GNU :program:`gettext` to include meta-data as
+the translation for the empty string. This meta-data is in :rfc:`822`\ -style
+``key: value`` pairs, and should contain the ``Project-Id-Version`` key. If the
+key ``Content-Type`` is found, then the ``charset`` property is used to
+initialize the "protected" :attr:`_charset` instance variable, defaulting to
+``None`` if not found. If the charset encoding is specified, then all message
+ids and message strings read from the catalog are converted to Unicode using
+this encoding. The :meth:`ugettext` method always returns a Unicode, while the
+:meth:`gettext` returns an encoded 8-bit string. For the message id arguments
+of both methods, either Unicode strings or 8-bit strings containing only
+US-ASCII characters are acceptable. Note that the Unicode version of the
+methods (i.e. :meth:`ugettext` and :meth:`ungettext`) are the recommended
+interface to use for internationalized Python programs.
+
+The entire set of key/value pairs are placed into a dictionary and set as the
+"protected" :attr:`_info` instance variable.
+
+If the :file:`.mo` file's magic number is invalid, or if other problems occur
+while reading the file, instantiating a :class:`GNUTranslations` class can raise
+:exc:`IOError`.
+
+The following methods are overridden from the base class implementation:
+
+
+.. method:: GNUTranslations.gettext(message)
+
+ Look up the *message* id in the catalog and return the corresponding message
+ string, as an 8-bit string encoded with the catalog's charset encoding, if
+ known. If there is no entry in the catalog for the *message* id, and a fallback
+ has been set, the look up is forwarded to the fallback's :meth:`gettext` method.
+ Otherwise, the *message* id is returned.
+
+
+.. method:: GNUTranslations.lgettext(message)
+
+ Equivalent to :meth:`gettext`, but the translation is returned in the preferred
+ system encoding, if no other encoding was explicitly set with
+ :meth:`set_output_charset`.
+
+ .. versionadded:: 2.4
+
+
+.. method:: GNUTranslations.ugettext(message)
+
+ Look up the *message* id in the catalog and return the corresponding message
+ string, as a Unicode string. If there is no entry in the catalog for the
+ *message* id, and a fallback has been set, the look up is forwarded to the
+ fallback's :meth:`ugettext` method. Otherwise, the *message* id is returned.
+
+
+.. method:: GNUTranslations.ngettext(singular, plural, n)
+
+ Do a plural-forms lookup of a message id. *singular* is used as the message id
+ for purposes of lookup in the catalog, while *n* is used to determine which
+ plural form to use. The returned message string is an 8-bit string encoded with
+ the catalog's charset encoding, if known.
+
+ If the message id is not found in the catalog, and a fallback is specified, the
+ request is forwarded to the fallback's :meth:`ngettext` method. Otherwise, when
+ *n* is 1 *singular* is returned, and *plural* is returned in all other cases.
+
+ .. versionadded:: 2.3
+
+
+.. method:: GNUTranslations.lngettext(singular, plural, n)
+
+ Equivalent to :meth:`gettext`, but the translation is returned in the preferred
+ system encoding, if no other encoding was explicitly set with
+ :meth:`set_output_charset`.
+
+ .. versionadded:: 2.4
+
+
+.. method:: GNUTranslations.ungettext(singular, plural, n)
+
+ Do a plural-forms lookup of a message id. *singular* is used as the message id
+ for purposes of lookup in the catalog, while *n* is used to determine which
+ plural form to use. The returned message string is a Unicode string.
+
+ If the message id is not found in the catalog, and a fallback is specified, the
+ request is forwarded to the fallback's :meth:`ungettext` method. Otherwise,
+ when *n* is 1 *singular* is returned, and *plural* is returned in all other
+ cases.
+
+ Here is an example::
+
+ n = len(os.listdir('.'))
+ cat = GNUTranslations(somefile)
+ message = cat.ungettext(
+ 'There is %(num)d file in this directory',
+ 'There are %(num)d files in this directory',
+ n) % {'num': n}
+
+ .. versionadded:: 2.3
+
+
+Solaris message catalog support
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The Solaris operating system defines its own binary :file:`.mo` file format, but
+since no documentation can be found on this format, it is not supported at this
+time.
+
+
+The Catalog constructor
+^^^^^^^^^^^^^^^^^^^^^^^
+
+.. index:: single: GNOME
+
+GNOME uses a version of the :mod:`gettext` module by James Henstridge, but this
+version has a slightly different API. Its documented usage was::
+
+ import gettext
+ cat = gettext.Catalog(domain, localedir)
+ _ = cat.gettext
+ print _('hello world')
+
+For compatibility with this older module, the function :func:`Catalog` is an
+alias for the :func:`translation` function described above.
+
+One difference between this module and Henstridge's: his catalog objects
+supported access through a mapping API, but this appears to be unused and so is
+not currently supported.
+
+
+Internationalizing your programs and modules
+--------------------------------------------
+
+Internationalization (I18N) refers to the operation by which a program is made
+aware of multiple languages. Localization (L10N) refers to the adaptation of
+your program, once internationalized, to the local language and cultural habits.
+In order to provide multilingual messages for your Python programs, you need to
+take the following steps:
+
+#. prepare your program or module by specially marking translatable strings
+
+#. run a suite of tools over your marked files to generate raw messages catalogs
+
+#. create language specific translations of the message catalogs
+
+#. use the :mod:`gettext` module so that message strings are properly translated
+
+In order to prepare your code for I18N, you need to look at all the strings in
+your files. Any string that needs to be translated should be marked by wrapping
+it in ``_('...')`` --- that is, a call to the function :func:`_`. For example::
+
+ filename = 'mylog.txt'
+ message = _('writing a log message')
+ fp = open(filename, 'w')
+ fp.write(message)
+ fp.close()
+
+In this example, the string ``'writing a log message'`` is marked as a candidate
+for translation, while the strings ``'mylog.txt'`` and ``'w'`` are not.
+
+The Python distribution comes with two tools which help you generate the message
+catalogs once you've prepared your source code. These may or may not be
+available from a binary distribution, but they can be found in a source
+distribution, in the :file:`Tools/i18n` directory.
+
+The :program:`pygettext` [#]_ program scans all your Python source code looking
+for the strings you previously marked as translatable. It is similar to the GNU
+:program:`gettext` program except that it understands all the intricacies of
+Python source code, but knows nothing about C or C++ source code. You don't
+need GNU ``gettext`` unless you're also going to be translating C code (such as
+C extension modules).
+
+:program:`pygettext` generates textual Uniforum-style human readable message
+catalog :file:`.pot` files, essentially structured human readable files which
+contain every marked string in the source code, along with a placeholder for the
+translation strings. :program:`pygettext` is a command line script that supports
+a similar command line interface as :program:`xgettext`; for details on its use,
+run::
+
+ pygettext.py --help
+
+Copies of these :file:`.pot` files are then handed over to the individual human
+translators who write language-specific versions for every supported natural
+language. They send you back the filled in language-specific versions as a
+:file:`.po` file. Using the :program:`msgfmt.py` [#]_ program (in the
+:file:`Tools/i18n` directory), you take the :file:`.po` files from your
+translators and generate the machine-readable :file:`.mo` binary catalog files.
+The :file:`.mo` files are what the :mod:`gettext` module uses for the actual
+translation processing during run-time.
+
+How you use the :mod:`gettext` module in your code depends on whether you are
+internationalizing a single module or your entire application. The next two
+sections will discuss each case.
+
+
+Localizing your module
+^^^^^^^^^^^^^^^^^^^^^^
+
+If you are localizing your module, you must take care not to make global
+changes, e.g. to the built-in namespace. You should not use the GNU ``gettext``
+API but instead the class-based API.
+
+Let's say your module is called "spam" and the module's various natural language
+translation :file:`.mo` files reside in :file:`/usr/share/locale` in GNU
+:program:`gettext` format. Here's what you would put at the top of your
+module::
+
+ import gettext
+ t = gettext.translation('spam', '/usr/share/locale')
+ _ = t.lgettext
+
+If your translators were providing you with Unicode strings in their :file:`.po`
+files, you'd instead do::
+
+ import gettext
+ t = gettext.translation('spam', '/usr/share/locale')
+ _ = t.ugettext
+
+
+Localizing your application
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If you are localizing your application, you can install the :func:`_` function
+globally into the built-in namespace, usually in the main driver file of your
+application. This will let all your application-specific files just use
+``_('...')`` without having to explicitly install it in each file.
+
+In the simple case then, you need only add the following bit of code to the main
+driver file of your application::
+
+ import gettext
+ gettext.install('myapplication')
+
+If you need to set the locale directory or the *unicode* flag, you can pass
+these into the :func:`install` function::
+
+ import gettext
+ gettext.install('myapplication', '/usr/share/locale', unicode=1)
+
+
+Changing languages on the fly
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If your program needs to support many languages at the same time, you may want
+to create multiple translation instances and then switch between them
+explicitly, like so::
+
+ import gettext
+
+ lang1 = gettext.translation('myapplication', languages=['en'])
+ lang2 = gettext.translation('myapplication', languages=['fr'])
+ lang3 = gettext.translation('myapplication', languages=['de'])
+
+ # start by using language1
+ lang1.install()
+
+ # ... time goes by, user selects language 2
+ lang2.install()
+
+ # ... more time goes by, user selects language 3
+ lang3.install()
+
+
+Deferred translations
+^^^^^^^^^^^^^^^^^^^^^
+
+In most coding situations, strings are translated where they are coded.
+Occasionally however, you need to mark strings for translation, but defer actual
+translation until later. A classic example is::
+
+ animals = ['mollusk',
+ 'albatross',
+ 'rat',
+ 'penguin',
+ 'python',
+ ]
+ # ...
+ for a in animals:
+ print a
+
+Here, you want to mark the strings in the ``animals`` list as being
+translatable, but you don't actually want to translate them until they are
+printed.
+
+Here is one way you can handle this situation::
+
+ def _(message): return message
+
+ animals = [_('mollusk'),
+ _('albatross'),
+ _('rat'),
+ _('penguin'),
+ _('python'),
+ ]
+
+ del _
+
+ # ...
+ for a in animals:
+ print _(a)
+
+This works because the dummy definition of :func:`_` simply returns the string
+unchanged. And this dummy definition will temporarily override any definition
+of :func:`_` in the built-in namespace (until the :keyword:`del` command). Take
+care, though if you have a previous definition of :func:`_` in the local
+namespace.
+
+Note that the second use of :func:`_` will not identify "a" as being
+translatable to the :program:`pygettext` program, since it is not a string.
+
+Another way to handle this is with the following example::
+
+ def N_(message): return message
+
+ animals = [N_('mollusk'),
+ N_('albatross'),
+ N_('rat'),
+ N_('penguin'),
+ N_('python'),
+ ]
+
+ # ...
+ for a in animals:
+ print _(a)
+
+In this case, you are marking translatable strings with the function :func:`N_`,
+[#]_ which won't conflict with any definition of :func:`_`. However, you will
+need to teach your message extraction program to look for translatable strings
+marked with :func:`N_`. :program:`pygettext` and :program:`xpot` both support
+this through the use of command line switches.
+
+
+:func:`gettext` vs. :func:`lgettext`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In Python 2.4 the :func:`lgettext` family of functions were introduced. The
+intention of these functions is to provide an alternative which is more
+compliant with the current implementation of GNU gettext. Unlike
+:func:`gettext`, which returns strings encoded with the same codeset used in the
+translation file, :func:`lgettext` will return strings encoded with the
+preferred system encoding, as returned by :func:`locale.getpreferredencoding`.
+Also notice that Python 2.4 introduces new functions to explicitly choose the
+codeset used in translated strings. If a codeset is explicitly set, even
+:func:`lgettext` will return translated strings in the requested codeset, as
+would be expected in the GNU gettext implementation.
+
+
+Acknowledgements
+----------------
+
+The following people contributed code, feedback, design suggestions, previous
+implementations, and valuable experience to the creation of this module:
+
+* Peter Funk
+
+* James Henstridge
+
+* Juan David Ibáñez Palomar
+
+* Marc-André Lemburg
+
+* Martin von Löwis
+
+* François Pinard
+
+* Barry Warsaw
+
+* Gustavo Niemeyer
+
+.. rubric:: Footnotes
+
+.. [#] The default locale directory is system dependent; for example, on RedHat Linux
+ it is :file:`/usr/share/locale`, but on Solaris it is :file:`/usr/lib/locale`.
+ The :mod:`gettext` module does not try to support these system dependent
+ defaults; instead its default is :file:`sys.prefix/share/locale`. For this
+ reason, it is always best to call :func:`bindtextdomain` with an explicit
+ absolute path at the start of your application.
+
+.. [#] See the footnote for :func:`bindtextdomain` above.
+
+.. [#] François Pinard has written a program called :program:`xpot` which does a
+ similar job. It is available as part of his :program:`po-utils` package at http
+ ://po-utils.progiciels-bpi.ca/.
+
+.. [#] :program:`msgfmt.py` is binary compatible with GNU :program:`msgfmt` except that
+ it provides a simpler, all-Python implementation. With this and
+ :program:`pygettext.py`, you generally won't need to install the GNU
+ :program:`gettext` package to internationalize your Python applications.
+
+.. [#] The choice of :func:`N_` here is totally arbitrary; it could have just as easily
+ been :func:`MarkThisStringForTranslation`.
+
diff --git a/Doc/library/glob.rst b/Doc/library/glob.rst
new file mode 100644
index 0000000000..80bdac2108
--- /dev/null
+++ b/Doc/library/glob.rst
@@ -0,0 +1,54 @@
+
+:mod:`glob` --- Unix style pathname pattern expansion
+=====================================================
+
+.. module:: glob
+ :synopsis: Unix shell style pathname pattern expansion.
+
+
+.. index:: single: filenames; pathname expansion
+
+The :mod:`glob` module finds all the pathnames matching a specified pattern
+according to the rules used by the Unix shell. No tilde expansion is done, but
+``*``, ``?``, and character ranges expressed with ``[]`` will be correctly
+matched. This is done by using the :func:`os.listdir` and
+:func:`fnmatch.fnmatch` functions in concert, and not by actually invoking a
+subshell. (For tilde and shell variable expansion, use
+:func:`os.path.expanduser` and :func:`os.path.expandvars`.)
+
+
+.. function:: glob(pathname)
+
+ Return a possibly-empty list of path names that match *pathname*, which must be
+ a string containing a path specification. *pathname* can be either absolute
+ (like :file:`/usr/src/Python-1.5/Makefile`) or relative (like
+ :file:`../../Tools/\*/\*.gif`), and can contain shell-style wildcards. Broken
+ symlinks are included in the results (as in the shell).
+
+
+.. function:: iglob(pathname)
+
+ Return an iterator which yields the same values as :func:`glob` without actually
+ storing them all simultaneously.
+
+ .. versionadded:: 2.5
+
+For example, consider a directory containing only the following files:
+:file:`1.gif`, :file:`2.txt`, and :file:`card.gif`. :func:`glob` will produce
+the following results. Notice how any leading components of the path are
+preserved. ::
+
+ >>> import glob
+ >>> glob.glob('./[0-9].*')
+ ['./1.gif', './2.txt']
+ >>> glob.glob('*.gif')
+ ['1.gif', 'card.gif']
+ >>> glob.glob('?.gif')
+ ['1.gif']
+
+
+.. seealso::
+
+ Module :mod:`fnmatch`
+ Shell-style filename (not path) expansion
+
diff --git a/Doc/library/grp.rst b/Doc/library/grp.rst
new file mode 100644
index 0000000000..a71c308d5d
--- /dev/null
+++ b/Doc/library/grp.rst
@@ -0,0 +1,63 @@
+
+:mod:`grp` --- The group database
+=================================
+
+.. module:: grp
+ :platform: Unix
+ :synopsis: The group database (getgrnam() and friends).
+
+
+This module provides access to the Unix group database. It is available on all
+Unix versions.
+
+Group database entries are reported as a tuple-like object, whose attributes
+correspond to the members of the ``group`` structure (Attribute field below, see
+``<pwd.h>``):
+
++-------+-----------+---------------------------------+
+| Index | Attribute | Meaning |
++=======+===========+=================================+
+| 0 | gr_name | the name of the group |
++-------+-----------+---------------------------------+
+| 1 | gr_passwd | the (encrypted) group password; |
+| | | often empty |
++-------+-----------+---------------------------------+
+| 2 | gr_gid | the numerical group ID |
++-------+-----------+---------------------------------+
+| 3 | gr_mem | all the group member's user |
+| | | names |
++-------+-----------+---------------------------------+
+
+The gid is an integer, name and password are strings, and the member list is a
+list of strings. (Note that most users are not explicitly listed as members of
+the group they are in according to the password database. Check both databases
+to get complete membership information.)
+
+It defines the following items:
+
+
+.. function:: getgrgid(gid)
+
+ Return the group database entry for the given numeric group ID. :exc:`KeyError`
+ is raised if the entry asked for cannot be found.
+
+
+.. function:: getgrnam(name)
+
+ Return the group database entry for the given group name. :exc:`KeyError` is
+ raised if the entry asked for cannot be found.
+
+
+.. function:: getgrall()
+
+ Return a list of all available group entries, in arbitrary order.
+
+
+.. seealso::
+
+ Module :mod:`pwd`
+ An interface to the user database, similar to this.
+
+ Module :mod:`spwd`
+ An interface to the shadow password database, similar to this.
+
diff --git a/Doc/library/gzip.rst b/Doc/library/gzip.rst
new file mode 100644
index 0000000000..5978031eb6
--- /dev/null
+++ b/Doc/library/gzip.rst
@@ -0,0 +1,68 @@
+
+:mod:`gzip` --- Support for :program:`gzip` files
+=================================================
+
+.. module:: gzip
+ :synopsis: Interfaces for gzip compression and decompression using file objects.
+
+
+The data compression provided by the ``zlib`` module is compatible with that
+used by the GNU compression program :program:`gzip`. Accordingly, the
+:mod:`gzip` module provides the :class:`GzipFile` class to read and write
+:program:`gzip`\ -format files, automatically compressing or decompressing the
+data so it looks like an ordinary file object. Note that additional file
+formats which can be decompressed by the :program:`gzip` and :program:`gunzip`
+programs, such as those produced by :program:`compress` and :program:`pack`,
+are not supported by this module.
+
+The module defines the following items:
+
+
+.. class:: GzipFile([filename[, mode[, compresslevel[, fileobj]]]])
+
+ Constructor for the :class:`GzipFile` class, which simulates most of the methods
+ of a file object, with the exception of the :meth:`readinto` and
+ :meth:`truncate` methods. At least one of *fileobj* and *filename* must be
+ given a non-trivial value.
+
+ The new class instance is based on *fileobj*, which can be a regular file, a
+ :class:`StringIO` object, or any other object which simulates a file. It
+ defaults to ``None``, in which case *filename* is opened to provide a file
+ object.
+
+ When *fileobj* is not ``None``, the *filename* argument is only used to be
+ included in the :program:`gzip` file header, which may includes the original
+ filename of the uncompressed file. It defaults to the filename of *fileobj*, if
+ discernible; otherwise, it defaults to the empty string, and in this case the
+ original filename is not included in the header.
+
+ The *mode* argument can be any of ``'r'``, ``'rb'``, ``'a'``, ``'ab'``, ``'w'``,
+ or ``'wb'``, depending on whether the file will be read or written. The default
+ is the mode of *fileobj* if discernible; otherwise, the default is ``'rb'``. If
+ not given, the 'b' flag will be added to the mode to ensure the file is opened
+ in binary mode for cross-platform portability.
+
+ The *compresslevel* argument is an integer from ``1`` to ``9`` controlling the
+ level of compression; ``1`` is fastest and produces the least compression, and
+ ``9`` is slowest and produces the most compression. The default is ``9``.
+
+ Calling a :class:`GzipFile` object's :meth:`close` method does not close
+ *fileobj*, since you might wish to append more material after the compressed
+ data. This also allows you to pass a :class:`StringIO` object opened for
+ writing as *fileobj*, and retrieve the resulting memory buffer using the
+ :class:`StringIO` object's :meth:`getvalue` method.
+
+
+.. function:: open(filename[, mode[, compresslevel]])
+
+ This is a shorthand for ``GzipFile(filename,`` ``mode,`` ``compresslevel)``.
+ The *filename* argument is required; *mode* defaults to ``'rb'`` and
+ *compresslevel* defaults to ``9``.
+
+
+.. seealso::
+
+ Module :mod:`zlib`
+ The basic data compression module needed to support the :program:`gzip` file
+ format.
+
diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst
new file mode 100644
index 0000000000..f255554574
--- /dev/null
+++ b/Doc/library/hashlib.rst
@@ -0,0 +1,121 @@
+
+:mod:`hashlib` --- Secure hashes and message digests
+====================================================
+
+.. module:: hashlib
+ :synopsis: Secure hash and message digest algorithms.
+.. moduleauthor:: Gregory P. Smith <greg@users.sourceforge.net>
+.. sectionauthor:: Gregory P. Smith <greg@users.sourceforge.net>
+
+
+.. versionadded:: 2.5
+
+.. index::
+ single: message digest, MD5
+ single: secure hash algorithm, SHA1, SHA224, SHA256, SHA384, SHA512
+
+This module implements a common interface to many different secure hash and
+message digest algorithms. Included are the FIPS secure hash algorithms SHA1,
+SHA224, SHA256, SHA384, and SHA512 (defined in FIPS 180-2) as well as RSA's MD5
+algorithm (defined in Internet :rfc:`1321`). The terms secure hash and message
+digest are interchangeable. Older algorithms were called message digests. The
+modern term is secure hash.
+
+.. warning::
+
+ Some algorithms have known hash collision weaknesses, see the FAQ at the end.
+
+There is one constructor method named for each type of :dfn:`hash`. All return
+a hash object with the same simple interface. For example: use :func:`sha1` to
+create a SHA1 hash object. You can now feed this object with arbitrary strings
+using the :meth:`update` method. At any point you can ask it for the
+:dfn:`digest` of the concatenation of the strings fed to it so far using the
+:meth:`digest` or :meth:`hexdigest` methods.
+
+.. index:: single: OpenSSL
+
+Constructors for hash algorithms that are always present in this module are
+:func:`md5`, :func:`sha1`, :func:`sha224`, :func:`sha256`, :func:`sha384`, and
+:func:`sha512`. Additional algorithms may also be available depending upon the
+OpenSSL library that Python uses on your platform.
+
+For example, to obtain the digest of the string ``'Nobody inspects the spammish
+repetition'``::
+
+ >>> import hashlib
+ >>> m = hashlib.md5()
+ >>> m.update("Nobody inspects")
+ >>> m.update(" the spammish repetition")
+ >>> m.digest()
+ '\xbbd\x9c\x83\xdd\x1e\xa5\xc9\xd9\xde\xc9\xa1\x8d\xf0\xff\xe9'
+
+More condensed::
+
+ >>> hashlib.sha224("Nobody inspects the spammish repetition").hexdigest()
+ 'a4337bc45a8fc544c03f52dc550cd6e1e87021bc896588bd79e901e2'
+
+A generic :func:`new` constructor that takes the string name of the desired
+algorithm as its first parameter also exists to allow access to the above listed
+hashes as well as any other algorithms that your OpenSSL library may offer. The
+named constructors are much faster than :func:`new` and should be preferred.
+
+Using :func:`new` with an algorithm provided by OpenSSL::
+
+ >>> h = hashlib.new('ripemd160')
+ >>> h.update("Nobody inspects the spammish repetition")
+ >>> h.hexdigest()
+ 'cc4a5ce1b3df48aec5d22d1f16b894a0b894eccc'
+
+The following values are provided as constant attributes of the hash objects
+returned by the constructors:
+
+
+.. data:: digest_size
+
+ The size of the resulting digest in bytes.
+
+A hash object has the following methods:
+
+
+.. method:: hash.update(arg)
+
+ Update the hash object with the string *arg*. Repeated calls are equivalent to
+ a single call with the concatenation of all the arguments: ``m.update(a);
+ m.update(b)`` is equivalent to ``m.update(a+b)``.
+
+
+.. method:: hash.digest()
+
+ Return the digest of the strings passed to the :meth:`update` method so far.
+ This is a string of :attr:`digest_size` bytes which may contain non-ASCII
+ characters, including null bytes.
+
+
+.. method:: hash.hexdigest()
+
+ Like :meth:`digest` except the digest is returned as a string of double length,
+ containing only hexadecimal digits. This may be used to exchange the value
+ safely in email or other non-binary environments.
+
+
+.. method:: hash.copy()
+
+ Return a copy ("clone") of the hash object. This can be used to efficiently
+ compute the digests of strings that share a common initial substring.
+
+
+.. seealso::
+
+ Module :mod:`hmac`
+ A module to generate message authentication codes using hashes.
+
+ Module :mod:`base64`
+ Another way to encode binary hashes for non-binary environments.
+
+ http://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf
+ The FIPS 180-2 publication on Secure Hash Algorithms.
+
+ http://www.cryptography.com/cnews/hash.html
+ Hash Collision FAQ with information on which algorithms have known issues and
+ what that means regarding their use.
+
diff --git a/Doc/library/heapq.rst b/Doc/library/heapq.rst
new file mode 100644
index 0000000000..2d38c26151
--- /dev/null
+++ b/Doc/library/heapq.rst
@@ -0,0 +1,224 @@
+
+:mod:`heapq` --- Heap queue algorithm
+=====================================
+
+.. module:: heapq
+ :synopsis: Heap queue algorithm (a.k.a. priority queue).
+.. moduleauthor:: Kevin O'Connor
+.. sectionauthor:: Guido van Rossum <guido@python.org>
+.. sectionauthor:: François Pinard
+
+
+.. % Theoretical explanation:
+
+.. versionadded:: 2.3
+
+This module provides an implementation of the heap queue algorithm, also known
+as the priority queue algorithm.
+
+Heaps are arrays for which ``heap[k] <= heap[2*k+1]`` and ``heap[k] <=
+heap[2*k+2]`` for all *k*, counting elements from zero. For the sake of
+comparison, non-existing elements are considered to be infinite. The
+interesting property of a heap is that ``heap[0]`` is always its smallest
+element.
+
+The API below differs from textbook heap algorithms in two aspects: (a) We use
+zero-based indexing. This makes the relationship between the index for a node
+and the indexes for its children slightly less obvious, but is more suitable
+since Python uses zero-based indexing. (b) Our pop method returns the smallest
+item, not the largest (called a "min heap" in textbooks; a "max heap" is more
+common in texts because of its suitability for in-place sorting).
+
+These two make it possible to view the heap as a regular Python list without
+surprises: ``heap[0]`` is the smallest item, and ``heap.sort()`` maintains the
+heap invariant!
+
+To create a heap, use a list initialized to ``[]``, or you can transform a
+populated list into a heap via function :func:`heapify`.
+
+The following functions are provided:
+
+
+.. function:: heappush(heap, item)
+
+ Push the value *item* onto the *heap*, maintaining the heap invariant.
+
+
+.. function:: heappop(heap)
+
+ Pop and return the smallest item from the *heap*, maintaining the heap
+ invariant. If the heap is empty, :exc:`IndexError` is raised.
+
+
+.. function:: heapify(x)
+
+ Transform list *x* into a heap, in-place, in linear time.
+
+
+.. function:: heapreplace(heap, item)
+
+ Pop and return the smallest item from the *heap*, and also push the new *item*.
+ The heap size doesn't change. If the heap is empty, :exc:`IndexError` is raised.
+ This is more efficient than :func:`heappop` followed by :func:`heappush`, and
+ can be more appropriate when using a fixed-size heap. Note that the value
+ returned may be larger than *item*! That constrains reasonable uses of this
+ routine unless written as part of a conditional replacement::
+
+ if item > heap[0]:
+ item = heapreplace(heap, item)
+
+Example of use::
+
+ >>> from heapq import heappush, heappop
+ >>> heap = []
+ >>> data = [1, 3, 5, 7, 9, 2, 4, 6, 8, 0]
+ >>> for item in data:
+ ... heappush(heap, item)
+ ...
+ >>> ordered = []
+ >>> while heap:
+ ... ordered.append(heappop(heap))
+ ...
+ >>> print ordered
+ [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+ >>> data.sort()
+ >>> print data == ordered
+ True
+ >>>
+
+The module also offers three general purpose functions based on heaps.
+
+
+.. function:: merge(*iterables)
+
+ Merge multiple sorted inputs into a single sorted output (for example, merge
+ timestamped entries from multiple log files). Returns an iterator over over the
+ sorted values.
+
+ Similar to ``sorted(itertools.chain(*iterables))`` but returns an iterable, does
+ not pull the data into memory all at once, and assumes that each of the input
+ streams is already sorted (smallest to largest).
+
+ .. versionadded:: 2.6
+
+
+.. function:: nlargest(n, iterable[, key])
+
+ Return a list with the *n* largest elements from the dataset defined by
+ *iterable*. *key*, if provided, specifies a function of one argument that is
+ used to extract a comparison key from each element in the iterable:
+ ``key=str.lower`` Equivalent to: ``sorted(iterable, key=key,
+ reverse=True)[:n]``
+
+ .. versionadded:: 2.4
+
+ .. versionchanged:: 2.5
+ Added the optional *key* argument.
+
+
+.. function:: nsmallest(n, iterable[, key])
+
+ Return a list with the *n* smallest elements from the dataset defined by
+ *iterable*. *key*, if provided, specifies a function of one argument that is
+ used to extract a comparison key from each element in the iterable:
+ ``key=str.lower`` Equivalent to: ``sorted(iterable, key=key)[:n]``
+
+ .. versionadded:: 2.4
+
+ .. versionchanged:: 2.5
+ Added the optional *key* argument.
+
+The latter two functions perform best for smaller values of *n*. For larger
+values, it is more efficient to use the :func:`sorted` function. Also, when
+``n==1``, it is more efficient to use the builtin :func:`min` and :func:`max`
+functions.
+
+
+Theory
+------
+
+(This explanation is due to François Pinard. The Python code for this module
+was contributed by Kevin O'Connor.)
+
+Heaps are arrays for which ``a[k] <= a[2*k+1]`` and ``a[k] <= a[2*k+2]`` for all
+*k*, counting elements from 0. For the sake of comparison, non-existing
+elements are considered to be infinite. The interesting property of a heap is
+that ``a[0]`` is always its smallest element.
+
+The strange invariant above is meant to be an efficient memory representation
+for a tournament. The numbers below are *k*, not ``a[k]``::
+
+ 0
+
+ 1 2
+
+ 3 4 5 6
+
+ 7 8 9 10 11 12 13 14
+
+ 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
+
+In the tree above, each cell *k* is topping ``2*k+1`` and ``2*k+2``. In an usual
+binary tournament we see in sports, each cell is the winner over the two cells
+it tops, and we can trace the winner down the tree to see all opponents s/he
+had. However, in many computer applications of such tournaments, we do not need
+to trace the history of a winner. To be more memory efficient, when a winner is
+promoted, we try to replace it by something else at a lower level, and the rule
+becomes that a cell and the two cells it tops contain three different items, but
+the top cell "wins" over the two topped cells.
+
+If this heap invariant is protected at all time, index 0 is clearly the overall
+winner. The simplest algorithmic way to remove it and find the "next" winner is
+to move some loser (let's say cell 30 in the diagram above) into the 0 position,
+and then percolate this new 0 down the tree, exchanging values, until the
+invariant is re-established. This is clearly logarithmic on the total number of
+items in the tree. By iterating over all items, you get an O(n log n) sort.
+
+A nice feature of this sort is that you can efficiently insert new items while
+the sort is going on, provided that the inserted items are not "better" than the
+last 0'th element you extracted. This is especially useful in simulation
+contexts, where the tree holds all incoming events, and the "win" condition
+means the smallest scheduled time. When an event schedule other events for
+execution, they are scheduled into the future, so they can easily go into the
+heap. So, a heap is a good structure for implementing schedulers (this is what
+I used for my MIDI sequencer :-).
+
+Various structures for implementing schedulers have been extensively studied,
+and heaps are good for this, as they are reasonably speedy, the speed is almost
+constant, and the worst case is not much different than the average case.
+However, there are other representations which are more efficient overall, yet
+the worst cases might be terrible.
+
+Heaps are also very useful in big disk sorts. You most probably all know that a
+big sort implies producing "runs" (which are pre-sorted sequences, which size is
+usually related to the amount of CPU memory), followed by a merging passes for
+these runs, which merging is often very cleverly organised [#]_. It is very
+important that the initial sort produces the longest runs possible. Tournaments
+are a good way to that. If, using all the memory available to hold a
+tournament, you replace and percolate items that happen to fit the current run,
+you'll produce runs which are twice the size of the memory for random input, and
+much better for input fuzzily ordered.
+
+Moreover, if you output the 0'th item on disk and get an input which may not fit
+in the current tournament (because the value "wins" over the last output value),
+it cannot fit in the heap, so the size of the heap decreases. The freed memory
+could be cleverly reused immediately for progressively building a second heap,
+which grows at exactly the same rate the first heap is melting. When the first
+heap completely vanishes, you switch heaps and start a new run. Clever and
+quite effective!
+
+In a word, heaps are useful memory structures to know. I use them in a few
+applications, and I think it is good to keep a 'heap' module around. :-)
+
+.. rubric:: Footnotes
+
+.. [#] The disk balancing algorithms which are current, nowadays, are more annoying
+ than clever, and this is a consequence of the seeking capabilities of the disks.
+ On devices which cannot seek, like big tape drives, the story was quite
+ different, and one had to be very clever to ensure (far in advance) that each
+ tape movement will be the most effective possible (that is, will best
+ participate at "progressing" the merge). Some tapes were even able to read
+ backwards, and this was also used to avoid the rewinding time. Believe me, real
+ good tape sorts were quite spectacular to watch! From all times, sorting has
+ always been a Great Art! :-)
+
diff --git a/Doc/library/hmac.rst b/Doc/library/hmac.rst
new file mode 100644
index 0000000000..10d41f700d
--- /dev/null
+++ b/Doc/library/hmac.rst
@@ -0,0 +1,61 @@
+
+:mod:`hmac` --- Keyed-Hashing for Message Authentication
+========================================================
+
+.. module:: hmac
+ :synopsis: Keyed-Hashing for Message Authentication (HMAC) implementation for Python.
+.. moduleauthor:: Gerhard Häring <ghaering@users.sourceforge.net>
+.. sectionauthor:: Gerhard Häring <ghaering@users.sourceforge.net>
+
+
+.. versionadded:: 2.2
+
+This module implements the HMAC algorithm as described by :rfc:`2104`.
+
+
+.. function:: new(key[, msg[, digestmod]])
+
+ Return a new hmac object. If *msg* is present, the method call ``update(msg)``
+ is made. *digestmod* is the digest constructor or module for the HMAC object to
+ use. It defaults to the :func:`hashlib.md5` constructor.
+
+ .. note::
+
+ The md5 hash has known weaknesses but remains the default for backwards
+ compatibility. Choose a better one for your application.
+
+An HMAC object has the following methods:
+
+
+.. method:: hmac.update(msg)
+
+ Update the hmac object with the string *msg*. Repeated calls are equivalent to
+ a single call with the concatenation of all the arguments: ``m.update(a);
+ m.update(b)`` is equivalent to ``m.update(a + b)``.
+
+
+.. method:: hmac.digest()
+
+ Return the digest of the strings passed to the :meth:`update` method so far.
+ This string will be the same length as the *digest_size* of the digest given to
+ the constructor. It may contain non-ASCII characters, including NUL bytes.
+
+
+.. method:: hmac.hexdigest()
+
+ Like :meth:`digest` except the digest is returned as a string twice the length
+ containing only hexadecimal digits. This may be used to exchange the value
+ safely in email or other non-binary environments.
+
+
+.. method:: hmac.copy()
+
+ Return a copy ("clone") of the hmac object. This can be used to efficiently
+ compute the digests of strings that share a common initial substring.
+
+
+.. seealso::
+
+ Module :mod:`hashlib`
+ The python module providing secure hash functions.
+
diff --git a/Doc/library/hotshot.rst b/Doc/library/hotshot.rst
new file mode 100644
index 0000000000..f6b5b13708
--- /dev/null
+++ b/Doc/library/hotshot.rst
@@ -0,0 +1,152 @@
+
+:mod:`hotshot` --- High performance logging profiler
+====================================================
+
+.. module:: hotshot
+ :synopsis: High performance logging profiler, mostly written in C.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Anthony Baxter <anthony@interlink.com.au>
+
+
+.. versionadded:: 2.2
+
+This module provides a nicer interface to the :mod:`_hotshot` C module. Hotshot
+is a replacement for the existing :mod:`profile` module. As it's written mostly
+in C, it should result in a much smaller performance impact than the existing
+:mod:`profile` module.
+
+.. note::
+
+ The :mod:`hotshot` module focuses on minimizing the overhead while profiling, at
+ the expense of long data post-processing times. For common usages it is
+ recommended to use :mod:`cProfile` instead. :mod:`hotshot` is not maintained and
+ might be removed from the standard library in the future.
+
+.. versionchanged:: 2.5
+ the results should be more meaningful than in the past: the timing core
+ contained a critical bug.
+
+.. warning::
+
+ The :mod:`hotshot` profiler does not yet work well with threads. It is useful to
+ use an unthreaded script to run the profiler over the code you're interested in
+ measuring if at all possible.
+
+
+.. class:: Profile(logfile[, lineevents[, linetimings]])
+
+ The profiler object. The argument *logfile* is the name of a log file to use for
+ logged profile data. The argument *lineevents* specifies whether to generate
+ events for every source line, or just on function call/return. It defaults to
+ ``0`` (only log function call/return). The argument *linetimings* specifies
+ whether to record timing information. It defaults to ``1`` (store timing
+ information).
+
+
+.. _hotshot-objects:
+
+Profile Objects
+---------------
+
+Profile objects have the following methods:
+
+
+.. method:: Profile.addinfo(key, value)
+
+ Add an arbitrary labelled value to the profile output.
+
+
+.. method:: Profile.close()
+
+ Close the logfile and terminate the profiler.
+
+
+.. method:: Profile.fileno()
+
+ Return the file descriptor of the profiler's log file.
+
+
+.. method:: Profile.run(cmd)
+
+ Profile an :func:`exec`\ -compatible string in the script environment. The
+ globals from the :mod:`__main__` module are used as both the globals and locals
+ for the script.
+
+
+.. method:: Profile.runcall(func, *args, **keywords)
+
+ Profile a single call of a callable. Additional positional and keyword arguments
+ may be passed along; the result of the call is returned, and exceptions are
+ allowed to propagate cleanly, while ensuring that profiling is disabled on the
+ way out.
+
+
+.. method:: Profile.runctx(cmd, globals, locals)
+
+ Profile an :func:`exec`\ -compatible string in a specific environment. The
+ string is compiled before profiling begins.
+
+
+.. method:: Profile.start()
+
+ Start the profiler.
+
+
+.. method:: Profile.stop()
+
+ Stop the profiler.
+
+
+Using hotshot data
+------------------
+
+.. module:: hotshot.stats
+ :synopsis: Statistical analysis for Hotshot
+
+
+.. versionadded:: 2.2
+
+This module loads hotshot profiling data into the standard :mod:`pstats` Stats
+objects.
+
+
+.. function:: load(filename)
+
+ Load hotshot data from *filename*. Returns an instance of the
+ :class:`pstats.Stats` class.
+
+
+.. seealso::
+
+ Module :mod:`profile`
+ The :mod:`profile` module's :class:`Stats` class
+
+
+.. _hotshot-example:
+
+Example Usage
+-------------
+
+Note that this example runs the python "benchmark" pystones. It can take some
+time to run, and will produce large output files. ::
+
+ >>> import hotshot, hotshot.stats, test.pystone
+ >>> prof = hotshot.Profile("stones.prof")
+ >>> benchtime, stones = prof.runcall(test.pystone.pystones)
+ >>> prof.close()
+ >>> stats = hotshot.stats.load("stones.prof")
+ >>> stats.strip_dirs()
+ >>> stats.sort_stats('time', 'calls')
+ >>> stats.print_stats(20)
+ 850004 function calls in 10.090 CPU seconds
+
+ Ordered by: internal time, call count
+
+ ncalls tottime percall cumtime percall filename:lineno(function)
+ 1 3.295 3.295 10.090 10.090 pystone.py:79(Proc0)
+ 150000 1.315 0.000 1.315 0.000 pystone.py:203(Proc7)
+ 50000 1.313 0.000 1.463 0.000 pystone.py:229(Func2)
+ .
+ .
+ .
+
diff --git a/Doc/library/htmllib.rst b/Doc/library/htmllib.rst
new file mode 100644
index 0000000000..96a7d08125
--- /dev/null
+++ b/Doc/library/htmllib.rst
@@ -0,0 +1,186 @@
+
+:mod:`htmllib` --- A parser for HTML documents
+==============================================
+
+.. module:: htmllib
+ :synopsis: A parser for HTML documents.
+
+
+.. index::
+ single: HTML
+ single: hypertext
+
+.. index::
+ module: sgmllib
+ module: formatter
+ single: SGMLParser (in module sgmllib)
+
+This module defines a class which can serve as a base for parsing text files
+formatted in the HyperText Mark-up Language (HTML). The class is not directly
+concerned with I/O --- it must be provided with input in string form via a
+method, and makes calls to methods of a "formatter" object in order to produce
+output. The :class:`HTMLParser` class is designed to be used as a base class
+for other classes in order to add functionality, and allows most of its methods
+to be extended or overridden. In turn, this class is derived from and extends
+the :class:`SGMLParser` class defined in module :mod:`sgmllib`. The
+:class:`HTMLParser` implementation supports the HTML 2.0 language as described
+in :rfc:`1866`. Two implementations of formatter objects are provided in the
+:mod:`formatter` module; refer to the documentation for that module for
+information on the formatter interface.
+
+The following is a summary of the interface defined by
+:class:`sgmllib.SGMLParser`:
+
+* The interface to feed data to an instance is through the :meth:`feed` method,
+ which takes a string argument. This can be called with as little or as much
+ text at a time as desired; ``p.feed(a); p.feed(b)`` has the same effect as
+ ``p.feed(a+b)``. When the data contains complete HTML markup constructs, these
+ are processed immediately; incomplete constructs are saved in a buffer. To
+ force processing of all unprocessed data, call the :meth:`close` method.
+
+ For example, to parse the entire contents of a file, use::
+
+ parser.feed(open('myfile.html').read())
+ parser.close()
+
+* The interface to define semantics for HTML tags is very simple: derive a class
+ and define methods called :meth:`start_tag`, :meth:`end_tag`, or :meth:`do_tag`.
+ The parser will call these at appropriate moments: :meth:`start_tag` or
+ :meth:`do_tag` is called when an opening tag of the form ``<tag ...>`` is
+ encountered; :meth:`end_tag` is called when a closing tag of the form ``<tag>``
+ is encountered. If an opening tag requires a corresponding closing tag, like
+ ``<H1>`` ... ``</H1>``, the class should define the :meth:`start_tag` method; if
+ a tag requires no closing tag, like ``<P>``, the class should define the
+ :meth:`do_tag` method.
+
+The module defines a parser class and an exception:
+
+
+.. class:: HTMLParser(formatter)
+
+ This is the basic HTML parser class. It supports all entity names required by
+ the XHTML 1.0 Recommendation (http://www.w3.org/TR/xhtml1). It also defines
+ handlers for all HTML 2.0 and many HTML 3.0 and 3.2 elements.
+
+
+.. exception:: HTMLParseError
+
+ Exception raised by the :class:`HTMLParser` class when it encounters an error
+ while parsing.
+
+ .. versionadded:: 2.4
+
+
+.. seealso::
+
+ Module :mod:`formatter`
+ Interface definition for transforming an abstract flow of formatting events into
+ specific output events on writer objects.
+
+ Module :mod:`HTMLParser`
+ Alternate HTML parser that offers a slightly lower-level view of the input, but
+ is designed to work with XHTML, and does not implement some of the SGML syntax
+ not used in "HTML as deployed" and which isn't legal for XHTML.
+
+ Module :mod:`htmlentitydefs`
+ Definition of replacement text for XHTML 1.0 entities.
+
+ Module :mod:`sgmllib`
+ Base class for :class:`HTMLParser`.
+
+
+.. _html-parser-objects:
+
+HTMLParser Objects
+------------------
+
+In addition to tag methods, the :class:`HTMLParser` class provides some
+additional methods and instance variables for use within tag methods.
+
+
+.. attribute:: HTMLParser.formatter
+
+ This is the formatter instance associated with the parser.
+
+
+.. attribute:: HTMLParser.nofill
+
+ Boolean flag which should be true when whitespace should not be collapsed, or
+ false when it should be. In general, this should only be true when character
+ data is to be treated as "preformatted" text, as within a ``<PRE>`` element.
+ The default value is false. This affects the operation of :meth:`handle_data`
+ and :meth:`save_end`.
+
+
+.. method:: HTMLParser.anchor_bgn(href, name, type)
+
+ This method is called at the start of an anchor region. The arguments
+ correspond to the attributes of the ``<A>`` tag with the same names. The
+ default implementation maintains a list of hyperlinks (defined by the ``HREF``
+ attribute for ``<A>`` tags) within the document. The list of hyperlinks is
+ available as the data attribute :attr:`anchorlist`.
+
+
+.. method:: HTMLParser.anchor_end()
+
+ This method is called at the end of an anchor region. The default
+ implementation adds a textual footnote marker using an index into the list of
+ hyperlinks created by :meth:`anchor_bgn`.
+
+
+.. method:: HTMLParser.handle_image(source, alt[, ismap[, align[, width[, height]]]])
+
+ This method is called to handle images. The default implementation simply
+ passes the *alt* value to the :meth:`handle_data` method.
+
+
+.. method:: HTMLParser.save_bgn()
+
+ Begins saving character data in a buffer instead of sending it to the formatter
+ object. Retrieve the stored data via :meth:`save_end`. Use of the
+ :meth:`save_bgn` / :meth:`save_end` pair may not be nested.
+
+
+.. method:: HTMLParser.save_end()
+
+ Ends buffering character data and returns all data saved since the preceding
+ call to :meth:`save_bgn`. If the :attr:`nofill` flag is false, whitespace is
+ collapsed to single spaces. A call to this method without a preceding call to
+ :meth:`save_bgn` will raise a :exc:`TypeError` exception.
+
+
+:mod:`htmlentitydefs` --- Definitions of HTML general entities
+==============================================================
+
+.. module:: htmlentitydefs
+ :synopsis: Definitions of HTML general entities.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+This module defines three dictionaries, ``name2codepoint``, ``codepoint2name``,
+and ``entitydefs``. ``entitydefs`` is used by the :mod:`htmllib` module to
+provide the :attr:`entitydefs` member of the :class:`HTMLParser` class. The
+definition provided here contains all the entities defined by XHTML 1.0 that
+can be handled using simple textual substitution in the Latin-1 character set
+(ISO-8859-1).
+
+
+.. data:: entitydefs
+
+ A dictionary mapping XHTML 1.0 entity definitions to their replacement text in
+ ISO Latin-1.
+
+
+.. data:: name2codepoint
+
+ A dictionary that maps HTML entity names to the Unicode codepoints.
+
+ .. versionadded:: 2.3
+
+
+.. data:: codepoint2name
+
+ A dictionary that maps Unicode codepoints to HTML entity names.
+
+ .. versionadded:: 2.3
+
diff --git a/Doc/library/htmlparser.rst b/Doc/library/htmlparser.rst
new file mode 100644
index 0000000000..85a38fbe98
--- /dev/null
+++ b/Doc/library/htmlparser.rst
@@ -0,0 +1,183 @@
+
+:mod:`HTMLParser` --- Simple HTML and XHTML parser
+==================================================
+
+.. module:: HTMLParser
+ :synopsis: A simple parser that can handle HTML and XHTML.
+
+
+.. versionadded:: 2.2
+
+.. index::
+ single: HTML
+ single: XHTML
+
+This module defines a class :class:`HTMLParser` which serves as the basis for
+parsing text files formatted in HTML (HyperText Mark-up Language) and XHTML.
+Unlike the parser in :mod:`htmllib`, this parser is not based on the SGML parser
+in :mod:`sgmllib`.
+
+
+.. class:: HTMLParser()
+
+ The :class:`HTMLParser` class is instantiated without arguments.
+
+ An HTMLParser instance is fed HTML data and calls handler functions when tags
+ begin and end. The :class:`HTMLParser` class is meant to be overridden by the
+ user to provide a desired behavior.
+
+ Unlike the parser in :mod:`htmllib`, this parser does not check that end tags
+ match start tags or call the end-tag handler for elements which are closed
+ implicitly by closing an outer element.
+
+An exception is defined as well:
+
+
+.. exception:: HTMLParseError
+
+ Exception raised by the :class:`HTMLParser` class when it encounters an error
+ while parsing. This exception provides three attributes: :attr:`msg` is a brief
+ message explaining the error, :attr:`lineno` is the number of the line on which
+ the broken construct was detected, and :attr:`offset` is the number of
+ characters into the line at which the construct starts.
+
+:class:`HTMLParser` instances have the following methods:
+
+
+.. method:: HTMLParser.reset()
+
+ Reset the instance. Loses all unprocessed data. This is called implicitly at
+ instantiation time.
+
+
+.. method:: HTMLParser.feed(data)
+
+ Feed some text to the parser. It is processed insofar as it consists of
+ complete elements; incomplete data is buffered until more data is fed or
+ :meth:`close` is called.
+
+
+.. method:: HTMLParser.close()
+
+ Force processing of all buffered data as if it were followed by an end-of-file
+ mark. This method may be redefined by a derived class to define additional
+ processing at the end of the input, but the redefined version should always call
+ the :class:`HTMLParser` base class method :meth:`close`.
+
+
+.. method:: HTMLParser.getpos()
+
+ Return current line number and offset.
+
+
+.. method:: HTMLParser.get_starttag_text()
+
+ Return the text of the most recently opened start tag. This should not normally
+ be needed for structured processing, but may be useful in dealing with HTML "as
+ deployed" or for re-generating input with minimal changes (whitespace between
+ attributes can be preserved, etc.).
+
+
+.. method:: HTMLParser.handle_starttag(tag, attrs)
+
+ This method is called to handle the start of a tag. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+ The *tag* argument is the name of the tag converted to lower case. The *attrs*
+ argument is a list of ``(name, value)`` pairs containing the attributes found
+ inside the tag's ``<>`` brackets. The *name* will be translated to lower case,
+ and quotes in the *value* have been removed, and character and entity references
+ have been replaced. For instance, for the tag ``<A
+ HREF="http://www.cwi.nl/">``, this method would be called as
+ ``handle_starttag('a', [('href', 'http://www.cwi.nl/')])``.
+
+ .. versionchanged:: 2.6
+ All entity references from htmlentitydefs are now replaced in the attribute
+ values.
+
+
+.. method:: HTMLParser.handle_startendtag(tag, attrs)
+
+ Similar to :meth:`handle_starttag`, but called when the parser encounters an
+ XHTML-style empty tag (``<a .../>``). This method may be overridden by
+ subclasses which require this particular lexical information; the default
+ implementation simple calls :meth:`handle_starttag` and :meth:`handle_endtag`.
+
+
+.. method:: HTMLParser.handle_endtag(tag)
+
+ This method is called to handle the end tag of an element. It is intended to be
+ overridden by a derived class; the base class implementation does nothing. The
+ *tag* argument is the name of the tag converted to lower case.
+
+
+.. method:: HTMLParser.handle_data(data)
+
+ This method is called to process arbitrary data. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+
+.. method:: HTMLParser.handle_charref(name)
+
+ This method is called to process a character reference of the form ``&#ref;``.
+ It is intended to be overridden by a derived class; the base class
+ implementation does nothing.
+
+
+.. method:: HTMLParser.handle_entityref(name)
+
+ This method is called to process a general entity reference of the form
+ ``&name;`` where *name* is an general entity reference. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+
+.. method:: HTMLParser.handle_comment(data)
+
+ This method is called when a comment is encountered. The *comment* argument is
+ a string containing the text between the ``--`` and ``--`` delimiters, but not
+ the delimiters themselves. For example, the comment ``<!--text-->`` will cause
+ this method to be called with the argument ``'text'``. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+
+.. method:: HTMLParser.handle_decl(decl)
+
+ Method called when an SGML declaration is read by the parser. The *decl*
+ parameter will be the entire contents of the declaration inside the ``<!``...\
+ ``>`` markup. It is intended to be overridden by a derived class; the base
+ class implementation does nothing.
+
+
+.. method:: HTMLParser.handle_pi(data)
+
+ Method called when a processing instruction is encountered. The *data*
+ parameter will contain the entire processing instruction. For example, for the
+ processing instruction ``<?proc color='red'>``, this method would be called as
+ ``handle_pi("proc color='red'")``. It is intended to be overridden by a derived
+ class; the base class implementation does nothing.
+
+ .. note::
+
+ The :class:`HTMLParser` class uses the SGML syntactic rules for processing
+ instructions. An XHTML processing instruction using the trailing ``'?'`` will
+ cause the ``'?'`` to be included in *data*.
+
+
+.. _htmlparser-example:
+
+Example HTML Parser Application
+-------------------------------
+
+As a basic example, below is a very basic HTML parser that uses the
+:class:`HTMLParser` class to print out tags as they are encountered::
+
+ from HTMLParser import HTMLParser
+
+ class MyHTMLParser(HTMLParser):
+
+ def handle_starttag(self, tag, attrs):
+ print "Encountered the beginning of a %s tag" % tag
+
+ def handle_endtag(self, tag):
+ print "Encountered the end of a %s tag" % tag
+
diff --git a/Doc/library/httplib.rst b/Doc/library/httplib.rst
new file mode 100644
index 0000000000..aae2219cfb
--- /dev/null
+++ b/Doc/library/httplib.rst
@@ -0,0 +1,552 @@
+
+:mod:`httplib` --- HTTP protocol client
+=======================================
+
+.. module:: httplib
+ :synopsis: HTTP and HTTPS protocol client (requires sockets).
+
+
+.. index::
+ pair: HTTP; protocol
+ single: HTTP; httplib (standard module)
+
+.. index:: module: urllib
+
+This module defines classes which implement the client side of the HTTP and
+HTTPS protocols. It is normally not used directly --- the module :mod:`urllib`
+uses it to handle URLs that use HTTP and HTTPS.
+
+.. note::
+
+ HTTPS support is only available if the :mod:`socket` module was compiled with
+ SSL support.
+
+.. note::
+
+ The public interface for this module changed substantially in Python 2.0. The
+ :class:`HTTP` class is retained only for backward compatibility with 1.5.2. It
+ should not be used in new code. Refer to the online docstrings for usage.
+
+The module provides the following classes:
+
+
+.. class:: HTTPConnection(host[, port[, strict[, timeout]]])
+
+ An :class:`HTTPConnection` instance represents one transaction with an HTTP
+ server. It should be instantiated passing it a host and optional port number.
+ If no port number is passed, the port is extracted from the host string if it
+ has the form ``host:port``, else the default HTTP port (80) is used. When True,
+ the optional parameter *strict* causes ``BadStatusLine`` to be raised if the
+ status line can't be parsed as a valid HTTP/1.0 or 1.1 status line. If the
+ optional *timeout* parameter is given, connection attempts will timeout after
+ that many seconds (if it is not given or ``None``, the global default timeout
+ setting is used).
+
+ For example, the following calls all create instances that connect to the server
+ at the same host and port::
+
+ >>> h1 = httplib.HTTPConnection('www.cwi.nl')
+ >>> h2 = httplib.HTTPConnection('www.cwi.nl:80')
+ >>> h3 = httplib.HTTPConnection('www.cwi.nl', 80)
+ >>> h3 = httplib.HTTPConnection('www.cwi.nl', 80, timeout=10)
+
+ .. versionadded:: 2.0
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. class:: HTTPSConnection(host[, port[, key_file[, cert_file[, strict[, timeout]]]]])
+
+ A subclass of :class:`HTTPConnection` that uses SSL for communication with
+ secure servers. Default port is ``443``. *key_file* is the name of a PEM
+ formatted file that contains your private key. *cert_file* is a PEM formatted
+ certificate chain file.
+
+ .. warning::
+
+ This does not do any certificate verification!
+
+ .. versionadded:: 2.0
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. class:: HTTPResponse(sock[, debuglevel=0][, strict=0])
+
+ Class whose instances are returned upon successful connection. Not instantiated
+ directly by user.
+
+ .. versionadded:: 2.0
+
+The following exceptions are raised as appropriate:
+
+
+.. exception:: HTTPException
+
+ The base class of the other exceptions in this module. It is a subclass of
+ :exc:`Exception`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: NotConnected
+
+ A subclass of :exc:`HTTPException`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: InvalidURL
+
+ A subclass of :exc:`HTTPException`, raised if a port is given and is either
+ non-numeric or empty.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: UnknownProtocol
+
+ A subclass of :exc:`HTTPException`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: UnknownTransferEncoding
+
+ A subclass of :exc:`HTTPException`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: UnimplementedFileMode
+
+ A subclass of :exc:`HTTPException`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: IncompleteRead
+
+ A subclass of :exc:`HTTPException`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: ImproperConnectionState
+
+ A subclass of :exc:`HTTPException`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: CannotSendRequest
+
+ A subclass of :exc:`ImproperConnectionState`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: CannotSendHeader
+
+ A subclass of :exc:`ImproperConnectionState`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: ResponseNotReady
+
+ A subclass of :exc:`ImproperConnectionState`.
+
+ .. versionadded:: 2.0
+
+
+.. exception:: BadStatusLine
+
+ A subclass of :exc:`HTTPException`. Raised if a server responds with a HTTP
+ status code that we don't understand.
+
+ .. versionadded:: 2.0
+
+The constants defined in this module are:
+
+
+.. data:: HTTP_PORT
+
+ The default port for the HTTP protocol (always ``80``).
+
+
+.. data:: HTTPS_PORT
+
+ The default port for the HTTPS protocol (always ``443``).
+
+and also the following constants for integer status codes:
+
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| Constant | Value | Definition |
++==========================================+=========+=======================================================================+
+| :const:`CONTINUE` | ``100`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.1.1 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1.1>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`SWITCHING_PROTOCOLS` | ``101`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.1.2 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1.2>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`PROCESSING` | ``102`` | WEBDAV, `RFC 2518, Section 10.1 |
+| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_102>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`OK` | ``200`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.1 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.1>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`CREATED` | ``201`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.2 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.2>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`ACCEPTED` | ``202`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.3 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.3>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NON_AUTHORITATIVE_INFORMATION` | ``203`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.4 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.4>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NO_CONTENT` | ``204`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.5 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.5>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`RESET_CONTENT` | ``205`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.6 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.6>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`PARTIAL_CONTENT` | ``206`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.2.7 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.7>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`MULTI_STATUS` | ``207`` | WEBDAV `RFC 2518, Section 10.2 |
+| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_207>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`IM_USED` | ``226`` | Delta encoding in HTTP, |
+| | | :rfc:`3229`, Section 10.4.1 |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`MULTIPLE_CHOICES` | ``300`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.1 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.1>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`MOVED_PERMANENTLY` | ``301`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.2 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.2>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`FOUND` | ``302`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.3 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.3>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`SEE_OTHER` | ``303`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.4 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.4>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NOT_MODIFIED` | ``304`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.5 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.5>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`USE_PROXY` | ``305`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.6 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.6>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`TEMPORARY_REDIRECT` | ``307`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.3.8 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.8>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`BAD_REQUEST` | ``400`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.1 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.1>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`UNAUTHORIZED` | ``401`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.2 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.2>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`PAYMENT_REQUIRED` | ``402`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.3 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.3>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`FORBIDDEN` | ``403`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.4 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.4>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NOT_FOUND` | ``404`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.5 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.5>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`METHOD_NOT_ALLOWED` | ``405`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.6 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.6>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NOT_ACCEPTABLE` | ``406`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.7 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.7>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`PROXY_AUTHENTICATION_REQUIRED` | ``407`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.8 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.8>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`REQUEST_TIMEOUT` | ``408`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.9 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.9>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`CONFLICT` | ``409`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.10 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.10>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`GONE` | ``410`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.11 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.11>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`LENGTH_REQUIRED` | ``411`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.12 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.12>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`PRECONDITION_FAILED` | ``412`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.13 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.13>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`REQUEST_ENTITY_TOO_LARGE` | ``413`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.14 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.14>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`REQUEST_URI_TOO_LONG` | ``414`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.15 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.15>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`UNSUPPORTED_MEDIA_TYPE` | ``415`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.16 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.16>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`REQUESTED_RANGE_NOT_SATISFIABLE` | ``416`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.17 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.17>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`EXPECTATION_FAILED` | ``417`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.4.18 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.18>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`UNPROCESSABLE_ENTITY` | ``422`` | WEBDAV, `RFC 2518, Section 10.3 |
+| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_422>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`LOCKED` | ``423`` | WEBDAV `RFC 2518, Section 10.4 |
+| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_423>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`FAILED_DEPENDENCY` | ``424`` | WEBDAV, `RFC 2518, Section 10.5 |
+| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_424>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`UPGRADE_REQUIRED` | ``426`` | HTTP Upgrade to TLS, |
+| | | :rfc:`2817`, Section 6 |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`INTERNAL_SERVER_ERROR` | ``500`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.5.1 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NOT_IMPLEMENTED` | ``501`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.5.2 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.2>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`BAD_GATEWAY` | ``502`` | HTTP/1.1 `RFC 2616, Section |
+| | | 10.5.3 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.3>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`SERVICE_UNAVAILABLE` | ``503`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.5.4 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.4>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`GATEWAY_TIMEOUT` | ``504`` | HTTP/1.1 `RFC 2616, Section |
+| | | 10.5.5 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.5>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`HTTP_VERSION_NOT_SUPPORTED` | ``505`` | HTTP/1.1, `RFC 2616, Section |
+| | | 10.5.6 |
+| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.6>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`INSUFFICIENT_STORAGE` | ``507`` | WEBDAV, `RFC 2518, Section 10.6 |
+| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_507>`_ |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+| :const:`NOT_EXTENDED` | ``510`` | An HTTP Extension Framework, |
+| | | :rfc:`2774`, Section 7 |
++------------------------------------------+---------+-----------------------------------------------------------------------+
+
+
+.. data:: responses
+
+ This dictionary maps the HTTP 1.1 status codes to the W3C names.
+
+ Example: ``httplib.responses[httplib.NOT_FOUND]`` is ``'Not Found'``.
+
+ .. versionadded:: 2.5
+
+
+.. _httpconnection-objects:
+
+HTTPConnection Objects
+----------------------
+
+:class:`HTTPConnection` instances have the following methods:
+
+
+.. method:: HTTPConnection.request(method, url[, body[, headers]])
+
+ This will send a request to the server using the HTTP request method *method*
+ and the selector *url*. If the *body* argument is present, it should be a
+ string of data to send after the headers are finished. Alternatively, it may
+ be an open file object, in which case the contents of the file is sent; this
+ file object should support ``fileno()`` and ``read()`` methods. The header
+ Content-Length is automatically set to the correct value. The *headers*
+ argument should be a mapping of extra HTTP headers to send with the request.
+
+ .. versionchanged:: 2.6
+ *body* can be a file object.
+
+
+.. method:: HTTPConnection.getresponse()
+
+ Should be called after a request is sent to get the response from the server.
+ Returns an :class:`HTTPResponse` instance.
+
+ .. note::
+
+ Note that you must have read the whole response before you can send a new
+ request to the server.
+
+
+.. method:: HTTPConnection.set_debuglevel(level)
+
+ Set the debugging level (the amount of debugging output printed). The default
+ debug level is ``0``, meaning no debugging output is printed.
+
+
+.. method:: HTTPConnection.connect()
+
+ Connect to the server specified when the object was created.
+
+
+.. method:: HTTPConnection.close()
+
+ Close the connection to the server.
+
+As an alternative to using the :meth:`request` method described above, you can
+also send your request step by step, by using the four functions below.
+
+
+.. method:: HTTPConnection.putrequest(request, selector[, skip_host[, skip_accept_encoding]])
+
+ This should be the first call after the connection to the server has been made.
+ It sends a line to the server consisting of the *request* string, the *selector*
+ string, and the HTTP version (``HTTP/1.1``). To disable automatic sending of
+ ``Host:`` or ``Accept-Encoding:`` headers (for example to accept additional
+ content encodings), specify *skip_host* or *skip_accept_encoding* with non-False
+ values.
+
+ .. versionchanged:: 2.4
+ *skip_accept_encoding* argument added.
+
+
+.. method:: HTTPConnection.putheader(header, argument[, ...])
+
+ Send an :rfc:`822`\ -style header to the server. It sends a line to the server
+ consisting of the header, a colon and a space, and the first argument. If more
+ arguments are given, continuation lines are sent, each consisting of a tab and
+ an argument.
+
+
+.. method:: HTTPConnection.endheaders()
+
+ Send a blank line to the server, signalling the end of the headers.
+
+
+.. method:: HTTPConnection.send(data)
+
+ Send data to the server. This should be used directly only after the
+ :meth:`endheaders` method has been called and before :meth:`getresponse` is
+ called.
+
+
+.. _httpresponse-objects:
+
+HTTPResponse Objects
+--------------------
+
+:class:`HTTPResponse` instances have the following methods and attributes:
+
+
+.. method:: HTTPResponse.read([amt])
+
+ Reads and returns the response body, or up to the next *amt* bytes.
+
+
+.. method:: HTTPResponse.getheader(name[, default])
+
+ Get the contents of the header *name*, or *default* if there is no matching
+ header.
+
+
+.. method:: HTTPResponse.getheaders()
+
+ Return a list of (header, value) tuples.
+
+ .. versionadded:: 2.4
+
+
+.. attribute:: HTTPResponse.msg
+
+ A :class:`mimetools.Message` instance containing the response headers.
+
+
+.. attribute:: HTTPResponse.version
+
+ HTTP protocol version used by server. 10 for HTTP/1.0, 11 for HTTP/1.1.
+
+
+.. attribute:: HTTPResponse.status
+
+ Status code returned by server.
+
+
+.. attribute:: HTTPResponse.reason
+
+ Reason phrase returned by server.
+
+
+.. _httplib-examples:
+
+Examples
+--------
+
+Here is an example session that uses the ``GET`` method::
+
+ >>> import httplib
+ >>> conn = httplib.HTTPConnection("www.python.org")
+ >>> conn.request("GET", "/index.html")
+ >>> r1 = conn.getresponse()
+ >>> print r1.status, r1.reason
+ 200 OK
+ >>> data1 = r1.read()
+ >>> conn.request("GET", "/parrot.spam")
+ >>> r2 = conn.getresponse()
+ >>> print r2.status, r2.reason
+ 404 Not Found
+ >>> data2 = r2.read()
+ >>> conn.close()
+
+Here is an example session that shows how to ``POST`` requests::
+
+ >>> import httplib, urllib
+ >>> params = urllib.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0})
+ >>> headers = {"Content-type": "application/x-www-form-urlencoded",
+ ... "Accept": "text/plain"}
+ >>> conn = httplib.HTTPConnection("musi-cal.mojam.com:80")
+ >>> conn.request("POST", "/cgi-bin/query", params, headers)
+ >>> response = conn.getresponse()
+ >>> print response.status, response.reason
+ 200 OK
+ >>> data = response.read()
+ >>> conn.close()
+
diff --git a/Doc/library/i18n.rst b/Doc/library/i18n.rst
new file mode 100644
index 0000000000..8e5710254c
--- /dev/null
+++ b/Doc/library/i18n.rst
@@ -0,0 +1,19 @@
+
+.. _i18n:
+
+********************
+Internationalization
+********************
+
+The modules described in this chapter help you write software that is
+independent of language and locale by providing mechanisms for selecting a
+language to be used in program messages or by tailoring output to match local
+conventions.
+
+The list of modules described in this chapter is:
+
+
+.. toctree::
+
+ gettext.rst
+ locale.rst
diff --git a/Doc/library/ic.rst b/Doc/library/ic.rst
new file mode 100644
index 0000000000..d5e03bd4d3
--- /dev/null
+++ b/Doc/library/ic.rst
@@ -0,0 +1,119 @@
+
+:mod:`ic` --- Access to the Mac OS X Internet Config
+====================================================
+
+.. module:: ic
+ :platform: Mac
+ :synopsis: Access to the Mac OS X Internet Config.
+
+
+This module provides access to various internet-related preferences set through
+:program:`System Preferences` or the :program:`Finder`.
+
+.. index:: module: icglue
+
+There is a low-level companion module :mod:`icglue` which provides the basic
+Internet Config access functionality. This low-level module is not documented,
+but the docstrings of the routines document the parameters and the routine names
+are the same as for the Pascal or C API to Internet Config, so the standard IC
+programmers' documentation can be used if this module is needed.
+
+The :mod:`ic` module defines the :exc:`error` exception and symbolic names for
+all error codes Internet Config can produce; see the source for details.
+
+
+.. exception:: error
+
+ Exception raised on errors in the :mod:`ic` module.
+
+The :mod:`ic` module defines the following class and function:
+
+
+.. class:: IC([signature[, ic]])
+
+ Create an Internet Config object. The signature is a 4-character creator code of
+ the current application (default ``'Pyth'``) which may influence some of ICs
+ settings. The optional *ic* argument is a low-level ``icglue.icinstance``
+ created beforehand, this may be useful if you want to get preferences from a
+ different config file, etc.
+
+
+.. function:: launchurl(url[, hint])
+ parseurl(data[, start[, end[, hint]]])
+ mapfile(file)
+ maptypecreator(type, creator[, filename])
+ settypecreator(file)
+
+ These functions are "shortcuts" to the methods of the same name, described
+ below.
+
+
+IC Objects
+----------
+
+:class:`IC` objects have a mapping interface, hence to obtain the mail address
+you simply get ``ic['MailAddress']``. Assignment also works, and changes the
+option in the configuration file.
+
+The module knows about various datatypes, and converts the internal IC
+representation to a "logical" Python data structure. Running the :mod:`ic`
+module standalone will run a test program that lists all keys and values in your
+IC database, this will have to serve as documentation.
+
+If the module does not know how to represent the data it returns an instance of
+the ``ICOpaqueData`` type, with the raw data in its :attr:`data` attribute.
+Objects of this type are also acceptable values for assignment.
+
+Besides the dictionary interface, :class:`IC` objects have the following
+methods:
+
+
+.. method:: IC.launchurl(url[, hint])
+
+ Parse the given URL, launch the correct application and pass it the URL. The
+ optional *hint* can be a scheme name such as ``'mailto:'``, in which case
+ incomplete URLs are completed with this scheme. If *hint* is not provided,
+ incomplete URLs are invalid.
+
+
+.. method:: IC.parseurl(data[, start[, end[, hint]]])
+
+ Find an URL somewhere in *data* and return start position, end position and the
+ URL. The optional *start* and *end* can be used to limit the search, so for
+ instance if a user clicks in a long text field you can pass the whole text field
+ and the click-position in *start* and this routine will return the whole URL in
+ which the user clicked. As above, *hint* is an optional scheme used to complete
+ incomplete URLs.
+
+
+.. method:: IC.mapfile(file)
+
+ Return the mapping entry for the given *file*, which can be passed as either a
+ filename or an :func:`FSSpec` result, and which need not exist.
+
+ The mapping entry is returned as a tuple ``(version, type, creator, postcreator,
+ flags, extension, appname, postappname, mimetype, entryname)``, where *version*
+ is the entry version number, *type* is the 4-character filetype, *creator* is
+ the 4-character creator type, *postcreator* is the 4-character creator code of
+ an optional application to post-process the file after downloading, *flags* are
+ various bits specifying whether to transfer in binary or ascii and such,
+ *extension* is the filename extension for this file type, *appname* is the
+ printable name of the application to which this file belongs, *postappname* is
+ the name of the postprocessing application, *mimetype* is the MIME type of this
+ file and *entryname* is the name of this entry.
+
+
+.. method:: IC.maptypecreator(type, creator[, filename])
+
+ Return the mapping entry for files with given 4-character *type* and *creator*
+ codes. The optional *filename* may be specified to further help finding the
+ correct entry (if the creator code is ``'????'``, for instance).
+
+ The mapping entry is returned in the same format as for *mapfile*.
+
+
+.. method:: IC.settypecreator(file)
+
+ Given an existing *file*, specified either as a filename or as an :func:`FSSpec`
+ result, set its creator and type correctly based on its extension. The finder
+ is told about the change, so the finder icon will be updated quickly.
diff --git a/Doc/library/idle.rst b/Doc/library/idle.rst
new file mode 100644
index 0000000000..44b59e9f8e
--- /dev/null
+++ b/Doc/library/idle.rst
@@ -0,0 +1,288 @@
+.. _idle:
+
+Idle
+====
+
+.. moduleauthor:: Guido van Rossum <guido@Python.org>
+
+
+.. % \declaremodule{standard}{idle}
+.. % \modulesynopsis{A Python Integrated Development Environment}
+
+.. index::
+ single: Idle
+ single: Python Editor
+ single: Integrated Development Environment
+
+Idle is the Python IDE built with the :mod:`Tkinter` GUI toolkit.
+
+IDLE has the following features:
+
+* coded in 100% pure Python, using the :mod:`Tkinter` GUI toolkit
+
+* cross-platform: works on Windows and Unix (on Mac OS, there are currently
+ problems with Tcl/Tk)
+
+* multi-window text editor with multiple undo, Python colorizing and many other
+ features, e.g. smart indent and call tips
+
+* Python shell window (a.k.a. interactive interpreter)
+
+* debugger (not complete, but you can set breakpoints, view and step)
+
+
+Menus
+-----
+
+
+File menu
+^^^^^^^^^
+
+New window
+ create a new editing window
+
+Open...
+ open an existing file
+
+Open module...
+ open an existing module (searches sys.path)
+
+Class browser
+ show classes and methods in current file
+
+Path browser
+ show sys.path directories, modules, classes and methods
+
+.. index::
+ single: Class browser
+ single: Path browser
+
+Save
+ save current window to the associated file (unsaved windows have a \* before and
+ after the window title)
+
+Save As...
+ save current window to new file, which becomes the associated file
+
+Save Copy As...
+ save current window to different file without changing the associated file
+
+Close
+ close current window (asks to save if unsaved)
+
+Exit
+ close all windows and quit IDLE (asks to save if unsaved)
+
+
+Edit menu
+^^^^^^^^^
+
+Undo
+ Undo last change to current window (max 1000 changes)
+
+Redo
+ Redo last undone change to current window
+
+Cut
+ Copy selection into system-wide clipboard; then delete selection
+
+Copy
+ Copy selection into system-wide clipboard
+
+Paste
+ Insert system-wide clipboard into window
+
+Select All
+ Select the entire contents of the edit buffer
+
+Find...
+ Open a search dialog box with many options
+
+Find again
+ Repeat last search
+
+Find selection
+ Search for the string in the selection
+
+Find in Files...
+ Open a search dialog box for searching files
+
+Replace...
+ Open a search-and-replace dialog box
+
+Go to line
+ Ask for a line number and show that line
+
+Indent region
+ Shift selected lines right 4 spaces
+
+Dedent region
+ Shift selected lines left 4 spaces
+
+Comment out region
+ Insert ## in front of selected lines
+
+Uncomment region
+ Remove leading # or ## from selected lines
+
+Tabify region
+ Turns *leading* stretches of spaces into tabs
+
+Untabify region
+ Turn *all* tabs into the right number of spaces
+
+Expand word
+ Expand the word you have typed to match another word in the same buffer; repeat
+ to get a different expansion
+
+Format Paragraph
+ Reformat the current blank-line-separated paragraph
+
+Import module
+ Import or reload the current module
+
+Run script
+ Execute the current file in the __main__ namespace
+
+.. index::
+ single: Import module
+ single: Run script
+
+
+Windows menu
+^^^^^^^^^^^^
+
+Zoom Height
+ toggles the window between normal size (24x80) and maximum height.
+
+The rest of this menu lists the names of all open windows; select one to bring
+it to the foreground (deiconifying it if necessary).
+
+
+Debug menu (in the Python Shell window only)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Go to file/line
+ look around the insert point for a filename and linenumber, open the file, and
+ show the line.
+
+Open stack viewer
+ show the stack traceback of the last exception
+
+Debugger toggle
+ Run commands in the shell under the debugger
+
+JIT Stack viewer toggle
+ Open stack viewer on traceback
+
+.. index::
+ single: stack viewer
+ single: debugger
+
+
+Basic editing and navigation
+----------------------------
+
+* :kbd:`Backspace` deletes to the left; :kbd:`Del` deletes to the right
+
+* Arrow keys and :kbd:`Page Up`/:kbd:`Page Down` to move around
+
+* :kbd:`Home`/:kbd:`End` go to begin/end of line
+
+* :kbd:`C-Home`/:kbd:`C-End` go to begin/end of file
+
+* Some :program:`Emacs` bindings may also work, including :kbd:`C-B`,
+ :kbd:`C-P`, :kbd:`C-A`, :kbd:`C-E`, :kbd:`C-D`, :kbd:`C-L`
+
+
+Automatic indentation
+^^^^^^^^^^^^^^^^^^^^^
+
+After a block-opening statement, the next line is indented by 4 spaces (in the
+Python Shell window by one tab). After certain keywords (break, return etc.)
+the next line is dedented. In leading indentation, :kbd:`Backspace` deletes up
+to 4 spaces if they are there. :kbd:`Tab` inserts 1-4 spaces (in the Python
+Shell window one tab). See also the indent/dedent region commands in the edit
+menu.
+
+
+Python Shell window
+^^^^^^^^^^^^^^^^^^^
+
+* :kbd:`C-C` interrupts executing command
+
+* :kbd:`C-D` sends end-of-file; closes window if typed at a ``>>>`` prompt
+
+* :kbd:`Alt-p` retrieves previous command matching what you have typed
+
+* :kbd:`Alt-n` retrieves next
+
+* :kbd:`Return` while on any previous command retrieves that command
+
+* :kbd:`Alt-/` (Expand word) is also useful here
+
+.. index:: single: indentation
+
+
+Syntax colors
+-------------
+
+The coloring is applied in a background "thread," so you may occasionally see
+uncolorized text. To change the color scheme, edit the ``[Colors]`` section in
+:file:`config.txt`.
+
+Python syntax colors:
+ Keywords
+ orange
+
+ Strings
+ green
+
+ Comments
+ red
+
+ Definitions
+ blue
+
+Shell colors:
+ Console output
+ brown
+
+ stdout
+ blue
+
+ stderr
+ dark green
+
+ stdin
+ black
+
+
+Command line usage
+^^^^^^^^^^^^^^^^^^
+
+::
+
+ idle.py [-c command] [-d] [-e] [-s] [-t title] [arg] ...
+
+ -c command run this command
+ -d enable debugger
+ -e edit mode; arguments are files to be edited
+ -s run $IDLESTARTUP or $PYTHONSTARTUP first
+ -t title set title of shell window
+
+If there are arguments:
+
+#. If :option:`-e` is used, arguments are files opened for editing and
+ ``sys.argv`` reflects the arguments passed to IDLE itself.
+
+#. Otherwise, if :option:`-c` is used, all arguments are placed in
+ ``sys.argv[1:...]``, with ``sys.argv[0]`` set to ``'-c'``.
+
+#. Otherwise, if neither :option:`-e` nor :option:`-c` is used, the first
+ argument is a script which is executed with the remaining arguments in
+ ``sys.argv[1:...]`` and ``sys.argv[0]`` set to the script name. If the script
+ name is '-', no script is executed but an interactive Python session is started;
+ the arguments are still available in ``sys.argv``.
+
+
diff --git a/Doc/library/imaplib.rst b/Doc/library/imaplib.rst
new file mode 100644
index 0000000000..fc7c23041c
--- /dev/null
+++ b/Doc/library/imaplib.rst
@@ -0,0 +1,540 @@
+
+:mod:`imaplib` --- IMAP4 protocol client
+========================================
+
+.. module:: imaplib
+ :synopsis: IMAP4 protocol client (requires sockets).
+.. moduleauthor:: Piers Lauder <piers@communitysolutions.com.au>
+.. sectionauthor:: Piers Lauder <piers@communitysolutions.com.au>
+
+
+.. index::
+ pair: IMAP4; protocol
+ pair: IMAP4_SSL; protocol
+ pair: IMAP4_stream; protocol
+
+.. % Based on HTML documentation by Piers Lauder
+.. % <piers@communitysolutions.com.au>;
+.. % converted by Fred L. Drake, Jr. <fdrake@acm.org>.
+.. % Revised by ESR, January 2000.
+.. % Changes for IMAP4_SSL by Tino Lange <Tino.Lange@isg.de>, March 2002
+.. % Changes for IMAP4_stream by Piers Lauder
+.. % <piers@communitysolutions.com.au>, November 2002
+
+This module defines three classes, :class:`IMAP4`, :class:`IMAP4_SSL` and
+:class:`IMAP4_stream`, which encapsulate a connection to an IMAP4 server and
+implement a large subset of the IMAP4rev1 client protocol as defined in
+:rfc:`2060`. It is backward compatible with IMAP4 (:rfc:`1730`) servers, but
+note that the ``STATUS`` command is not supported in IMAP4.
+
+Three classes are provided by the :mod:`imaplib` module, :class:`IMAP4` is the
+base class:
+
+
+.. class:: IMAP4([host[, port]])
+
+ This class implements the actual IMAP4 protocol. The connection is created and
+ protocol version (IMAP4 or IMAP4rev1) is determined when the instance is
+ initialized. If *host* is not specified, ``''`` (the local host) is used. If
+ *port* is omitted, the standard IMAP4 port (143) is used.
+
+Three exceptions are defined as attributes of the :class:`IMAP4` class:
+
+
+.. exception:: IMAP4.error
+
+ Exception raised on any errors. The reason for the exception is passed to the
+ constructor as a string.
+
+
+.. exception:: IMAP4.abort
+
+ IMAP4 server errors cause this exception to be raised. This is a sub-class of
+ :exc:`IMAP4.error`. Note that closing the instance and instantiating a new one
+ will usually allow recovery from this exception.
+
+
+.. exception:: IMAP4.readonly
+
+ This exception is raised when a writable mailbox has its status changed by the
+ server. This is a sub-class of :exc:`IMAP4.error`. Some other client now has
+ write permission, and the mailbox will need to be re-opened to re-obtain write
+ permission.
+
+There's also a subclass for secure connections:
+
+
+.. class:: IMAP4_SSL([host[, port[, keyfile[, certfile]]]])
+
+ This is a subclass derived from :class:`IMAP4` that connects over an SSL
+ encrypted socket (to use this class you need a socket module that was compiled
+ with SSL support). If *host* is not specified, ``''`` (the local host) is used.
+ If *port* is omitted, the standard IMAP4-over-SSL port (993) is used. *keyfile*
+ and *certfile* are also optional - they can contain a PEM formatted private key
+ and certificate chain file for the SSL connection.
+
+The second subclass allows for connections created by a child process:
+
+
+.. class:: IMAP4_stream(command)
+
+ This is a subclass derived from :class:`IMAP4` that connects to the
+ ``stdin/stdout`` file descriptors created by passing *command* to
+ ``os.popen2()``.
+
+ .. versionadded:: 2.3
+
+The following utility functions are defined:
+
+
+.. function:: Internaldate2tuple(datestr)
+
+ Converts an IMAP4 INTERNALDATE string to Coordinated Universal Time. Returns a
+ :mod:`time` module tuple.
+
+
+.. function:: Int2AP(num)
+
+ Converts an integer into a string representation using characters from the set
+ [``A`` .. ``P``].
+
+
+.. function:: ParseFlags(flagstr)
+
+ Converts an IMAP4 ``FLAGS`` response to a tuple of individual flags.
+
+
+.. function:: Time2Internaldate(date_time)
+
+ Converts a :mod:`time` module tuple to an IMAP4 ``INTERNALDATE`` representation.
+ Returns a string in the form: ``"DD-Mmm-YYYY HH:MM:SS +HHMM"`` (including
+ double-quotes).
+
+Note that IMAP4 message numbers change as the mailbox changes; in particular,
+after an ``EXPUNGE`` command performs deletions the remaining messages are
+renumbered. So it is highly advisable to use UIDs instead, with the UID command.
+
+At the end of the module, there is a test section that contains a more extensive
+example of usage.
+
+
+.. seealso::
+
+ Documents describing the protocol, and sources and binaries for servers
+ implementing it, can all be found at the University of Washington's *IMAP
+ Information Center* (http://www.cac.washington.edu/imap/).
+
+
+.. _imap4-objects:
+
+IMAP4 Objects
+-------------
+
+All IMAP4rev1 commands are represented by methods of the same name, either
+upper-case or lower-case.
+
+All arguments to commands are converted to strings, except for ``AUTHENTICATE``,
+and the last argument to ``APPEND`` which is passed as an IMAP4 literal. If
+necessary (the string contains IMAP4 protocol-sensitive characters and isn't
+enclosed with either parentheses or double quotes) each string is quoted.
+However, the *password* argument to the ``LOGIN`` command is always quoted. If
+you want to avoid having an argument string quoted (eg: the *flags* argument to
+``STORE``) then enclose the string in parentheses (eg: ``r'(\Deleted)'``).
+
+Each command returns a tuple: ``(type, [data, ...])`` where *type* is usually
+``'OK'`` or ``'NO'``, and *data* is either the text from the command response,
+or mandated results from the command. Each *data* is either a string, or a
+tuple. If a tuple, then the first part is the header of the response, and the
+second part contains the data (ie: 'literal' value).
+
+The *message_set* options to commands below is a string specifying one or more
+messages to be acted upon. It may be a simple message number (``'1'``), a range
+of message numbers (``'2:4'``), or a group of non-contiguous ranges separated by
+commas (``'1:3,6:9'``). A range can contain an asterisk to indicate an infinite
+upper bound (``'3:*'``).
+
+An :class:`IMAP4` instance has the following methods:
+
+
+.. method:: IMAP4.append(mailbox, flags, date_time, message)
+
+ Append *message* to named mailbox.
+
+
+.. method:: IMAP4.authenticate(mechanism, authobject)
+
+ Authenticate command --- requires response processing.
+
+ *mechanism* specifies which authentication mechanism is to be used - it should
+ appear in the instance variable ``capabilities`` in the form ``AUTH=mechanism``.
+
+ *authobject* must be a callable object::
+
+ data = authobject(response)
+
+ It will be called to process server continuation responses. It should return
+ ``data`` that will be encoded and sent to server. It should return ``None`` if
+ the client abort response ``*`` should be sent instead.
+
+
+.. method:: IMAP4.check()
+
+ Checkpoint mailbox on server.
+
+
+.. method:: IMAP4.close()
+
+ Close currently selected mailbox. Deleted messages are removed from writable
+ mailbox. This is the recommended command before ``LOGOUT``.
+
+
+.. method:: IMAP4.copy(message_set, new_mailbox)
+
+ Copy *message_set* messages onto end of *new_mailbox*.
+
+
+.. method:: IMAP4.create(mailbox)
+
+ Create new mailbox named *mailbox*.
+
+
+.. method:: IMAP4.delete(mailbox)
+
+ Delete old mailbox named *mailbox*.
+
+
+.. method:: IMAP4.deleteacl(mailbox, who)
+
+ Delete the ACLs (remove any rights) set for who on mailbox.
+
+ .. versionadded:: 2.4
+
+
+.. method:: IMAP4.expunge()
+
+ Permanently remove deleted items from selected mailbox. Generates an ``EXPUNGE``
+ response for each deleted message. Returned data contains a list of ``EXPUNGE``
+ message numbers in order received.
+
+
+.. method:: IMAP4.fetch(message_set, message_parts)
+
+ Fetch (parts of) messages. *message_parts* should be a string of message part
+ names enclosed within parentheses, eg: ``"(UID BODY[TEXT])"``. Returned data
+ are tuples of message part envelope and data.
+
+
+.. method:: IMAP4.getacl(mailbox)
+
+ Get the ``ACL``\ s for *mailbox*. The method is non-standard, but is supported
+ by the ``Cyrus`` server.
+
+
+.. method:: IMAP4.getannotation(mailbox, entry, attribute)
+
+ Retrieve the specified ``ANNOTATION``\ s for *mailbox*. The method is
+ non-standard, but is supported by the ``Cyrus`` server.
+
+ .. versionadded:: 2.5
+
+
+.. method:: IMAP4.getquota(root)
+
+ Get the ``quota`` *root*'s resource usage and limits. This method is part of the
+ IMAP4 QUOTA extension defined in rfc2087.
+
+ .. versionadded:: 2.3
+
+
+.. method:: IMAP4.getquotaroot(mailbox)
+
+ Get the list of ``quota`` ``roots`` for the named *mailbox*. This method is part
+ of the IMAP4 QUOTA extension defined in rfc2087.
+
+ .. versionadded:: 2.3
+
+
+.. method:: IMAP4.list([directory[, pattern]])
+
+ List mailbox names in *directory* matching *pattern*. *directory* defaults to
+ the top-level mail folder, and *pattern* defaults to match anything. Returned
+ data contains a list of ``LIST`` responses.
+
+
+.. method:: IMAP4.login(user, password)
+
+ Identify the client using a plaintext password. The *password* will be quoted.
+
+
+.. method:: IMAP4.login_cram_md5(user, password)
+
+ Force use of ``CRAM-MD5`` authentication when identifying the client to protect
+ the password. Will only work if the server ``CAPABILITY`` response includes the
+ phrase ``AUTH=CRAM-MD5``.
+
+ .. versionadded:: 2.3
+
+
+.. method:: IMAP4.logout()
+
+ Shutdown connection to server. Returns server ``BYE`` response.
+
+
+.. method:: IMAP4.lsub([directory[, pattern]])
+
+ List subscribed mailbox names in directory matching pattern. *directory*
+ defaults to the top level directory and *pattern* defaults to match any mailbox.
+ Returned data are tuples of message part envelope and data.
+
+
+.. method:: IMAP4.myrights(mailbox)
+
+ Show my ACLs for a mailbox (i.e. the rights that I have on mailbox).
+
+ .. versionadded:: 2.4
+
+
+.. method:: IMAP4.namespace()
+
+ Returns IMAP namespaces as defined in RFC2342.
+
+ .. versionadded:: 2.3
+
+
+.. method:: IMAP4.noop()
+
+ Send ``NOOP`` to server.
+
+
+.. method:: IMAP4.open(host, port)
+
+ Opens socket to *port* at *host*. The connection objects established by this
+ method will be used in the ``read``, ``readline``, ``send``, and ``shutdown``
+ methods. You may override this method.
+
+
+.. method:: IMAP4.partial(message_num, message_part, start, length)
+
+ Fetch truncated part of a message. Returned data is a tuple of message part
+ envelope and data.
+
+
+.. method:: IMAP4.proxyauth(user)
+
+ Assume authentication as *user*. Allows an authorised administrator to proxy
+ into any user's mailbox.
+
+ .. versionadded:: 2.3
+
+
+.. method:: IMAP4.read(size)
+
+ Reads *size* bytes from the remote server. You may override this method.
+
+
+.. method:: IMAP4.readline()
+
+ Reads one line from the remote server. You may override this method.
+
+
+.. method:: IMAP4.recent()
+
+ Prompt server for an update. Returned data is ``None`` if no new messages, else
+ value of ``RECENT`` response.
+
+
+.. method:: IMAP4.rename(oldmailbox, newmailbox)
+
+ Rename mailbox named *oldmailbox* to *newmailbox*.
+
+
+.. method:: IMAP4.response(code)
+
+ Return data for response *code* if received, or ``None``. Returns the given
+ code, instead of the usual type.
+
+
+.. method:: IMAP4.search(charset, criterion[, ...])
+
+ Search mailbox for matching messages. *charset* may be ``None``, in which case
+ no ``CHARSET`` will be specified in the request to the server. The IMAP
+ protocol requires that at least one criterion be specified; an exception will be
+ raised when the server returns an error.
+
+ Example::
+
+ # M is a connected IMAP4 instance...
+ typ, msgnums = M.search(None, 'FROM', '"LDJ"')
+
+ # or:
+ typ, msgnums = M.search(None, '(FROM "LDJ")')
+
+
+.. method:: IMAP4.select([mailbox[, readonly]])
+
+ Select a mailbox. Returned data is the count of messages in *mailbox*
+ (``EXISTS`` response). The default *mailbox* is ``'INBOX'``. If the *readonly*
+ flag is set, modifications to the mailbox are not allowed.
+
+
+.. method:: IMAP4.send(data)
+
+ Sends ``data`` to the remote server. You may override this method.
+
+
+.. method:: IMAP4.setacl(mailbox, who, what)
+
+ Set an ``ACL`` for *mailbox*. The method is non-standard, but is supported by
+ the ``Cyrus`` server.
+
+
+.. method:: IMAP4.setannotation(mailbox, entry, attribute[, ...])
+
+ Set ``ANNOTATION``\ s for *mailbox*. The method is non-standard, but is
+ supported by the ``Cyrus`` server.
+
+ .. versionadded:: 2.5
+
+
+.. method:: IMAP4.setquota(root, limits)
+
+ Set the ``quota`` *root*'s resource *limits*. This method is part of the IMAP4
+ QUOTA extension defined in rfc2087.
+
+ .. versionadded:: 2.3
+
+
+.. method:: IMAP4.shutdown()
+
+ Close connection established in ``open``. You may override this method.
+
+
+.. method:: IMAP4.socket()
+
+ Returns socket instance used to connect to server.
+
+
+.. method:: IMAP4.sort(sort_criteria, charset, search_criterion[, ...])
+
+ The ``sort`` command is a variant of ``search`` with sorting semantics for the
+ results. Returned data contains a space separated list of matching message
+ numbers.
+
+ Sort has two arguments before the *search_criterion* argument(s); a
+ parenthesized list of *sort_criteria*, and the searching *charset*. Note that
+ unlike ``search``, the searching *charset* argument is mandatory. There is also
+ a ``uid sort`` command which corresponds to ``sort`` the way that ``uid search``
+ corresponds to ``search``. The ``sort`` command first searches the mailbox for
+ messages that match the given searching criteria using the charset argument for
+ the interpretation of strings in the searching criteria. It then returns the
+ numbers of matching messages.
+
+ This is an ``IMAP4rev1`` extension command.
+
+
+.. method:: IMAP4.status(mailbox, names)
+
+ Request named status conditions for *mailbox*.
+
+
+.. method:: IMAP4.store(message_set, command, flag_list)
+
+ Alters flag dispositions for messages in mailbox. *command* is specified by
+ section 6.4.6 of :rfc:`2060` as being one of "FLAGS", "+FLAGS", or "-FLAGS",
+ optionally with a suffix of ".SILENT".
+
+ For example, to set the delete flag on all messages::
+
+ typ, data = M.search(None, 'ALL')
+ for num in data[0].split():
+ M.store(num, '+FLAGS', '\\Deleted')
+ M.expunge()
+
+
+.. method:: IMAP4.subscribe(mailbox)
+
+ Subscribe to new mailbox.
+
+
+.. method:: IMAP4.thread(threading_algorithm, charset, search_criterion[, ...])
+
+ The ``thread`` command is a variant of ``search`` with threading semantics for
+ the results. Returned data contains a space separated list of thread members.
+
+ Thread members consist of zero or more messages numbers, delimited by spaces,
+ indicating successive parent and child.
+
+ Thread has two arguments before the *search_criterion* argument(s); a
+ *threading_algorithm*, and the searching *charset*. Note that unlike
+ ``search``, the searching *charset* argument is mandatory. There is also a
+ ``uid thread`` command which corresponds to ``thread`` the way that ``uid
+ search`` corresponds to ``search``. The ``thread`` command first searches the
+ mailbox for messages that match the given searching criteria using the charset
+ argument for the interpretation of strings in the searching criteria. It then
+ returns the matching messages threaded according to the specified threading
+ algorithm.
+
+ This is an ``IMAP4rev1`` extension command.
+
+ .. versionadded:: 2.4
+
+
+.. method:: IMAP4.uid(command, arg[, ...])
+
+ Execute command args with messages identified by UID, rather than message
+ number. Returns response appropriate to command. At least one argument must be
+ supplied; if none are provided, the server will return an error and an exception
+ will be raised.
+
+
+.. method:: IMAP4.unsubscribe(mailbox)
+
+ Unsubscribe from old mailbox.
+
+
+.. method:: IMAP4.xatom(name[, arg[, ...]])
+
+ Allow simple extension commands notified by server in ``CAPABILITY`` response.
+
+Instances of :class:`IMAP4_SSL` have just one additional method:
+
+
+.. method:: IMAP4_SSL.ssl()
+
+ Returns SSLObject instance used for the secure connection with the server.
+
+The following attributes are defined on instances of :class:`IMAP4`:
+
+
+.. attribute:: IMAP4.PROTOCOL_VERSION
+
+ The most recent supported protocol in the ``CAPABILITY`` response from the
+ server.
+
+
+.. attribute:: IMAP4.debug
+
+ Integer value to control debugging output. The initialize value is taken from
+ the module variable ``Debug``. Values greater than three trace each command.
+
+
+.. _imap4-example:
+
+IMAP4 Example
+-------------
+
+Here is a minimal example (without error checking) that opens a mailbox and
+retrieves and prints all messages::
+
+ import getpass, imaplib
+
+ M = imaplib.IMAP4()
+ M.login(getpass.getuser(), getpass.getpass())
+ M.select()
+ typ, data = M.search(None, 'ALL')
+ for num in data[0].split():
+ typ, data = M.fetch(num, '(RFC822)')
+ print 'Message %s\n%s\n' % (num, data[0][1])
+ M.close()
+ M.logout()
+
diff --git a/Doc/library/imghdr.rst b/Doc/library/imghdr.rst
new file mode 100644
index 0000000000..90a83045c3
--- /dev/null
+++ b/Doc/library/imghdr.rst
@@ -0,0 +1,71 @@
+
+:mod:`imghdr` --- Determine the type of an image
+================================================
+
+.. module:: imghdr
+ :synopsis: Determine the type of image contained in a file or byte stream.
+
+
+The :mod:`imghdr` module determines the type of image contained in a file or
+byte stream.
+
+The :mod:`imghdr` module defines the following function:
+
+
+.. function:: what(filename[, h])
+
+ Tests the image data contained in the file named by *filename*, and returns a
+ string describing the image type. If optional *h* is provided, the *filename*
+ is ignored and *h* is assumed to contain the byte stream to test.
+
+The following image types are recognized, as listed below with the return value
+from :func:`what`:
+
++------------+-----------------------------------+
+| Value | Image format |
++============+===================================+
+| ``'rgb'`` | SGI ImgLib Files |
++------------+-----------------------------------+
+| ``'gif'`` | GIF 87a and 89a Files |
++------------+-----------------------------------+
+| ``'pbm'`` | Portable Bitmap Files |
++------------+-----------------------------------+
+| ``'pgm'`` | Portable Graymap Files |
++------------+-----------------------------------+
+| ``'ppm'`` | Portable Pixmap Files |
++------------+-----------------------------------+
+| ``'tiff'`` | TIFF Files |
++------------+-----------------------------------+
+| ``'rast'`` | Sun Raster Files |
++------------+-----------------------------------+
+| ``'xbm'`` | X Bitmap Files |
++------------+-----------------------------------+
+| ``'jpeg'`` | JPEG data in JFIF or Exif formats |
++------------+-----------------------------------+
+| ``'bmp'`` | BMP files |
++------------+-----------------------------------+
+| ``'png'`` | Portable Network Graphics |
++------------+-----------------------------------+
+
+.. versionadded:: 2.5
+ Exif detection.
+
+You can extend the list of file types :mod:`imghdr` can recognize by appending
+to this variable:
+
+
+.. data:: tests
+
+ A list of functions performing the individual tests. Each function takes two
+ arguments: the byte-stream and an open file-like object. When :func:`what` is
+ called with a byte-stream, the file-like object will be ``None``.
+
+ The test function should return a string describing the image type if the test
+ succeeded, or ``None`` if it failed.
+
+Example::
+
+ >>> import imghdr
+ >>> imghdr.what('/tmp/bass.gif')
+ 'gif'
+
diff --git a/Doc/library/imp.rst b/Doc/library/imp.rst
new file mode 100644
index 0000000000..f80bea34dd
--- /dev/null
+++ b/Doc/library/imp.rst
@@ -0,0 +1,298 @@
+
+:mod:`imp` --- Access the :keyword:`import` internals
+=====================================================
+
+.. module:: imp
+ :synopsis: Access the implementation of the import statement.
+
+
+.. index:: statement: import
+
+This module provides an interface to the mechanisms used to implement the
+:keyword:`import` statement. It defines the following constants and functions:
+
+
+.. function:: get_magic()
+
+ .. index:: pair: file; byte-code
+
+ Return the magic string value used to recognize byte-compiled code files
+ (:file:`.pyc` files). (This value may be different for each Python version.)
+
+
+.. function:: get_suffixes()
+
+ Return a list of triples, each describing a particular type of module. Each
+ triple has the form ``(suffix, mode, type)``, where *suffix* is a string to be
+ appended to the module name to form the filename to search for, *mode* is the
+ mode string to pass to the built-in :func:`open` function to open the file (this
+ can be ``'r'`` for text files or ``'rb'`` for binary files), and *type* is the
+ file type, which has one of the values :const:`PY_SOURCE`, :const:`PY_COMPILED`,
+ or :const:`C_EXTENSION`, described below.
+
+
+.. function:: find_module(name[, path])
+
+ Try to find the module *name* on the search path *path*. If *path* is a list of
+ directory names, each directory is searched for files with any of the suffixes
+ returned by :func:`get_suffixes` above. Invalid names in the list are silently
+ ignored (but all list items must be strings). If *path* is omitted or ``None``,
+ the list of directory names given by ``sys.path`` is searched, but first it
+ searches a few special places: it tries to find a built-in module with the given
+ name (:const:`C_BUILTIN`), then a frozen module (:const:`PY_FROZEN`), and on
+ some systems some other places are looked in as well (on the Mac, it looks for a
+ resource (:const:`PY_RESOURCE`); on Windows, it looks in the registry which may
+ point to a specific file).
+
+ If search is successful, the return value is a triple ``(file, pathname,
+ description)`` where *file* is an open file object positioned at the beginning,
+ *pathname* is the pathname of the file found, and *description* is a triple as
+ contained in the list returned by :func:`get_suffixes` describing the kind of
+ module found. If the module does not live in a file, the returned *file* is
+ ``None``, *filename* is the empty string, and the *description* tuple contains
+ empty strings for its suffix and mode; the module type is as indicate in
+ parentheses above. If the search is unsuccessful, :exc:`ImportError` is raised.
+ Other exceptions indicate problems with the arguments or environment.
+
+ This function does not handle hierarchical module names (names containing dots).
+ In order to find *P*.*M*, that is, submodule *M* of package *P*, use
+ :func:`find_module` and :func:`load_module` to find and load package *P*, and
+ then use :func:`find_module` with the *path* argument set to ``P.__path__``.
+ When *P* itself has a dotted name, apply this recipe recursively.
+
+
+.. function:: load_module(name, file, filename, description)
+
+ Load a module that was previously found by :func:`find_module` (or by an
+ otherwise conducted search yielding compatible results). This function does
+ more than importing the module: if the module was already imported, it will
+ reload the module! The *name* argument indicates the full module name (including
+ the package name, if this is a submodule of a package). The *file* argument is
+ an open file, and *filename* is the corresponding file name; these can be
+ ``None`` and ``''``, respectively, when the module is not being loaded from a
+ file. The *description* argument is a tuple, as would be returned by
+ :func:`get_suffixes`, describing what kind of module must be loaded.
+
+ If the load is successful, the return value is the module object; otherwise, an
+ exception (usually :exc:`ImportError`) is raised.
+
+ **Important:** the caller is responsible for closing the *file* argument, if it
+ was not ``None``, even when an exception is raised. This is best done using a
+ :keyword:`try` ... :keyword:`finally` statement.
+
+
+.. function:: new_module(name)
+
+ Return a new empty module object called *name*. This object is *not* inserted
+ in ``sys.modules``.
+
+
+.. function:: lock_held()
+
+ Return ``True`` if the import lock is currently held, else ``False``. On
+ platforms without threads, always return ``False``.
+
+ On platforms with threads, a thread executing an import holds an internal lock
+ until the import is complete. This lock blocks other threads from doing an
+ import until the original import completes, which in turn prevents other threads
+ from seeing incomplete module objects constructed by the original thread while
+ in the process of completing its import (and the imports, if any, triggered by
+ that).
+
+
+.. function:: acquire_lock()
+
+ Acquires the interpreter's import lock for the current thread. This lock should
+ be used by import hooks to ensure thread-safety when importing modules. On
+ platforms without threads, this function does nothing.
+
+ .. versionadded:: 2.3
+
+
+.. function:: release_lock()
+
+ Release the interpreter's import lock. On platforms without threads, this
+ function does nothing.
+
+ .. versionadded:: 2.3
+
+The following constants with integer values, defined in this module, are used to
+indicate the search result of :func:`find_module`.
+
+
+.. data:: PY_SOURCE
+
+ The module was found as a source file.
+
+
+.. data:: PY_COMPILED
+
+ The module was found as a compiled code object file.
+
+
+.. data:: C_EXTENSION
+
+ The module was found as dynamically loadable shared library.
+
+
+.. data:: PY_RESOURCE
+
+ The module was found as a Mac OS 9 resource. This value can only be returned on
+ a Mac OS 9 or earlier Macintosh.
+
+
+.. data:: PKG_DIRECTORY
+
+ The module was found as a package directory.
+
+
+.. data:: C_BUILTIN
+
+ The module was found as a built-in module.
+
+
+.. data:: PY_FROZEN
+
+ The module was found as a frozen module (see :func:`init_frozen`).
+
+The following constant and functions are obsolete; their functionality is
+available through :func:`find_module` or :func:`load_module`. They are kept
+around for backward compatibility:
+
+
+.. data:: SEARCH_ERROR
+
+ Unused.
+
+
+.. function:: init_builtin(name)
+
+ Initialize the built-in module called *name* and return its module object along
+ with storing it in ``sys.modules``. If the module was already initialized, it
+ will be initialized *again*. Re-initialization involves the copying of the
+ built-in module's ``__dict__`` from the cached module over the module's entry in
+ ``sys.modules``. If there is no built-in module called *name*, ``None`` is
+ returned.
+
+
+.. function:: init_frozen(name)
+
+ Initialize the frozen module called *name* and return its module object. If
+ the module was already initialized, it will be initialized *again*. If there
+ is no frozen module called *name*, ``None`` is returned. (Frozen modules are
+ modules written in Python whose compiled byte-code object is incorporated
+ into a custom-built Python interpreter by Python's :program:`freeze`
+ utility. See :file:`Tools/freeze/` for now.)
+
+
+.. function:: is_builtin(name)
+
+ Return ``1`` if there is a built-in module called *name* which can be
+ initialized again. Return ``-1`` if there is a built-in module called *name*
+ which cannot be initialized again (see :func:`init_builtin`). Return ``0`` if
+ there is no built-in module called *name*.
+
+
+.. function:: is_frozen(name)
+
+ Return ``True`` if there is a frozen module (see :func:`init_frozen`) called
+ *name*, or ``False`` if there is no such module.
+
+
+.. function:: load_compiled(name, pathname, [file])
+
+ .. index:: pair: file; byte-code
+
+ Load and initialize a module implemented as a byte-compiled code file and return
+ its module object. If the module was already initialized, it will be
+ initialized *again*. The *name* argument is used to create or access a module
+ object. The *pathname* argument points to the byte-compiled code file. The
+ *file* argument is the byte-compiled code file, open for reading in binary mode,
+ from the beginning. It must currently be a real file object, not a user-defined
+ class emulating a file.
+
+
+.. function:: load_dynamic(name, pathname[, file])
+
+ Load and initialize a module implemented as a dynamically loadable shared
+ library and return its module object. If the module was already initialized, it
+ will be initialized *again*. Re-initialization involves copying the ``__dict__``
+ attribute of the cached instance of the module over the value used in the module
+ cached in ``sys.modules``. The *pathname* argument must point to the shared
+ library. The *name* argument is used to construct the name of the
+ initialization function: an external C function called ``initname()`` in the
+ shared library is called. The optional *file* argument is ignored. (Note:
+ using shared libraries is highly system dependent, and not all systems support
+ it.)
+
+
+.. function:: load_source(name, pathname[, file])
+
+ Load and initialize a module implemented as a Python source file and return its
+ module object. If the module was already initialized, it will be initialized
+ *again*. The *name* argument is used to create or access a module object. The
+ *pathname* argument points to the source file. The *file* argument is the
+ source file, open for reading as text, from the beginning. It must currently be
+ a real file object, not a user-defined class emulating a file. Note that if a
+ properly matching byte-compiled file (with suffix :file:`.pyc` or :file:`.pyo`)
+ exists, it will be used instead of parsing the given source file.
+
+
+.. class:: NullImporter(path_string)
+
+ The :class:`NullImporter` type is a :pep:`302` import hook that handles
+ non-directory path strings by failing to find any modules. Calling this type
+ with an existing directory or empty string raises :exc:`ImportError`.
+ Otherwise, a :class:`NullImporter` instance is returned.
+
+ Python adds instances of this type to ``sys.path_importer_cache`` for any path
+ entries that are not directories and are not handled by any other path hooks on
+ ``sys.path_hooks``. Instances have only one method:
+
+
+ .. method:: NullImporter.find_module(fullname [, path])
+
+ This method always returns ``None``, indicating that the requested module could
+ not be found.
+
+ .. versionadded:: 2.5
+
+
+.. _examples-imp:
+
+Examples
+--------
+
+The following function emulates what was the standard import statement up to
+Python 1.4 (no hierarchical module names). (This *implementation* wouldn't work
+in that version, since :func:`find_module` has been extended and
+:func:`load_module` has been added in 1.4.) ::
+
+ import imp
+ import sys
+
+ def __import__(name, globals=None, locals=None, fromlist=None):
+ # Fast path: see if the module has already been imported.
+ try:
+ return sys.modules[name]
+ except KeyError:
+ pass
+
+ # If any of the following calls raises an exception,
+ # there's a problem we can't handle -- let the caller handle it.
+
+ fp, pathname, description = imp.find_module(name)
+
+ try:
+ return imp.load_module(name, fp, pathname, description)
+ finally:
+ # Since we may exit via an exception, close fp explicitly.
+ if fp:
+ fp.close()
+
+.. index:: module: knee
+
+A more complete example that implements hierarchical module names and includes a
+:func:`reload` function can be found in the module :mod:`knee`. The :mod:`knee`
+module can be found in :file:`Demo/imputil/` in the Python source distribution.
+
diff --git a/Doc/library/index.rst b/Doc/library/index.rst
new file mode 100644
index 0000000000..1e872ac257
--- /dev/null
+++ b/Doc/library/index.rst
@@ -0,0 +1,81 @@
+.. _library-index:
+
+###############################
+ The Python Standard Library
+###############################
+
+:Release: |version|
+:Date: |today|
+
+While the :ref:`reference-index` describes the exact syntax and
+semantics of the Python language, this library reference manual
+describes the standard library that is distributed with Python. It also
+describes some of the optional components that are commonly included
+in Python distributions.
+
+Python's standard library is very extensive, offering a wide range of
+facilities as indicated by the long table of contents listed below. The
+library contains built-in modules (written in C) that provide access to
+system functionality such as file I/O that would otherwise be
+inaccessible to Python programmers, as well as modules written in Python
+that provide standardized solutions for many problems that occur in
+everyday programming. Some of these modules are explicitly designed to
+encourage and enhance the portability of Python programs by abstracting
+away platform-specifics into platform-neutral APIs.
+
+The Python installers for the Windows and Mac platforms usually include
+the entire standard library and often also include many additional
+components. For Unix-like operating systems Python is normally provided
+as a collection of packages, so it may be necessary to use the packaging
+tools provided with the operating system to obtain some or all of the
+optional components.
+
+In addition to the standard library, there is a growing collection of
+over 2500 additional components available from the `Python Package Index
+<http://pypi.python.org/pypi>`_.
+
+
+.. toctree::
+ :maxdepth: 2
+
+ intro.rst
+ functions.rst
+ constants.rst
+ objects.rst
+ stdtypes.rst
+ exceptions.rst
+
+ strings.rst
+ datatypes.rst
+ numeric.rst
+ filesys.rst
+ persistence.rst
+ archiving.rst
+ fileformats.rst
+ crypto.rst
+ allos.rst
+ someos.rst
+ ipc.rst
+ netdata.rst
+ markup.rst
+ internet.rst
+ mm.rst
+ i18n.rst
+ frameworks.rst
+ tk.rst
+ development.rst
+ pdb.rst
+ profile.rst
+ hotshot.rst
+ timeit.rst
+ trace.rst
+ python.rst
+ custominterp.rst
+ modules.rst
+ language.rst
+ misc.rst
+ windows.rst
+ unix.rst
+ mac.rst
+ macosa.rst
+ undoc.rst
diff --git a/Doc/library/inspect.rst b/Doc/library/inspect.rst
new file mode 100644
index 0000000000..edec9d58f0
--- /dev/null
+++ b/Doc/library/inspect.rst
@@ -0,0 +1,507 @@
+
+:mod:`inspect` --- Inspect live objects
+=======================================
+
+.. module:: inspect
+ :synopsis: Extract information and source code from live objects.
+.. moduleauthor:: Ka-Ping Yee <ping@lfw.org>
+.. sectionauthor:: Ka-Ping Yee <ping@lfw.org>
+
+
+.. versionadded:: 2.1
+
+The :mod:`inspect` module provides several useful functions to help get
+information about live objects such as modules, classes, methods, functions,
+tracebacks, frame objects, and code objects. For example, it can help you
+examine the contents of a class, retrieve the source code of a method, extract
+and format the argument list for a function, or get all the information you need
+to display a detailed traceback.
+
+There are four main kinds of services provided by this module: type checking,
+getting source code, inspecting classes and functions, and examining the
+interpreter stack.
+
+
+.. _inspect-types:
+
+Types and members
+-----------------
+
+The :func:`getmembers` function retrieves the members of an object such as a
+class or module. The eleven functions whose names begin with "is" are mainly
+provided as convenient choices for the second argument to :func:`getmembers`.
+They also help you determine when you can expect to find the following special
+attributes:
+
++-----------+-----------------+---------------------------+-------+
+| Type | Attribute | Description | Notes |
++===========+=================+===========================+=======+
+| module | __doc__ | documentation string | |
++-----------+-----------------+---------------------------+-------+
+| | __file__ | filename (missing for | |
+| | | built-in modules) | |
++-----------+-----------------+---------------------------+-------+
+| class | __doc__ | documentation string | |
++-----------+-----------------+---------------------------+-------+
+| | __module__ | name of module in which | |
+| | | this class was defined | |
++-----------+-----------------+---------------------------+-------+
+| method | __doc__ | documentation string | |
++-----------+-----------------+---------------------------+-------+
+| | __name__ | name with which this | |
+| | | method was defined | |
++-----------+-----------------+---------------------------+-------+
+| | im_class | class object that asked | \(1) |
+| | | for this method | |
++-----------+-----------------+---------------------------+-------+
+| | im_func | function object | |
+| | | containing implementation | |
+| | | of method | |
++-----------+-----------------+---------------------------+-------+
+| | im_self | instance to which this | |
+| | | method is bound, or | |
+| | | ``None`` | |
++-----------+-----------------+---------------------------+-------+
+| function | __doc__ | documentation string | |
++-----------+-----------------+---------------------------+-------+
+| | __name__ | name with which this | |
+| | | function was defined | |
++-----------+-----------------+---------------------------+-------+
+| | __code__ | code object containing | |
+| | | compiled function | |
+| | | bytecode | |
++-----------+-----------------+---------------------------+-------+
+| | __defaults__ | tuple of any default | |
+| | | values for arguments | |
++-----------+-----------------+---------------------------+-------+
+| | __globals__ | global namespace in which | |
+| | | this function was defined | |
++-----------+-----------------+---------------------------+-------+
+| traceback | tb_frame | frame object at this | |
+| | | level | |
++-----------+-----------------+---------------------------+-------+
+| | tb_lasti | index of last attempted | |
+| | | instruction in bytecode | |
++-----------+-----------------+---------------------------+-------+
+| | tb_lineno | current line number in | |
+| | | Python source code | |
++-----------+-----------------+---------------------------+-------+
+| | tb_next | next inner traceback | |
+| | | object (called by this | |
+| | | level) | |
++-----------+-----------------+---------------------------+-------+
+| frame | f_back | next outer frame object | |
+| | | (this frame's caller) | |
++-----------+-----------------+---------------------------+-------+
+| | f_builtins | built-in namespace seen | |
+| | | by this frame | |
++-----------+-----------------+---------------------------+-------+
+| | f_code | code object being | |
+| | | executed in this frame | |
++-----------+-----------------+---------------------------+-------+
+| | f_exc_traceback | traceback if raised in | |
+| | | this frame, or ``None`` | |
++-----------+-----------------+---------------------------+-------+
+| | f_exc_type | exception type if raised | |
+| | | in this frame, or | |
+| | | ``None`` | |
++-----------+-----------------+---------------------------+-------+
+| | f_exc_value | exception value if raised | |
+| | | in this frame, or | |
+| | | ``None`` | |
++-----------+-----------------+---------------------------+-------+
+| | f_globals | global namespace seen by | |
+| | | this frame | |
++-----------+-----------------+---------------------------+-------+
+| | f_lasti | index of last attempted | |
+| | | instruction in bytecode | |
++-----------+-----------------+---------------------------+-------+
+| | f_lineno | current line number in | |
+| | | Python source code | |
++-----------+-----------------+---------------------------+-------+
+| | f_locals | local namespace seen by | |
+| | | this frame | |
++-----------+-----------------+---------------------------+-------+
+| | f_restricted | 0 or 1 if frame is in | |
+| | | restricted execution mode | |
++-----------+-----------------+---------------------------+-------+
+| | f_trace | tracing function for this | |
+| | | frame, or ``None`` | |
++-----------+-----------------+---------------------------+-------+
+| code | co_argcount | number of arguments (not | |
+| | | including \* or \*\* | |
+| | | args) | |
++-----------+-----------------+---------------------------+-------+
+| | co_code | string of raw compiled | |
+| | | bytecode | |
++-----------+-----------------+---------------------------+-------+
+| | co_consts | tuple of constants used | |
+| | | in the bytecode | |
++-----------+-----------------+---------------------------+-------+
+| | co_filename | name of file in which | |
+| | | this code object was | |
+| | | created | |
++-----------+-----------------+---------------------------+-------+
+| | co_firstlineno | number of first line in | |
+| | | Python source code | |
++-----------+-----------------+---------------------------+-------+
+| | co_flags | bitmap: 1=optimized ``|`` | |
+| | | 2=newlocals ``|`` 4=\*arg | |
+| | | ``|`` 8=\*\*arg | |
++-----------+-----------------+---------------------------+-------+
+| | co_lnotab | encoded mapping of line | |
+| | | numbers to bytecode | |
+| | | indices | |
++-----------+-----------------+---------------------------+-------+
+| | co_name | name with which this code | |
+| | | object was defined | |
++-----------+-----------------+---------------------------+-------+
+| | co_names | tuple of names of local | |
+| | | variables | |
++-----------+-----------------+---------------------------+-------+
+| | co_nlocals | number of local variables | |
++-----------+-----------------+---------------------------+-------+
+| | co_stacksize | virtual machine stack | |
+| | | space required | |
++-----------+-----------------+---------------------------+-------+
+| | co_varnames | tuple of names of | |
+| | | arguments and local | |
+| | | variables | |
++-----------+-----------------+---------------------------+-------+
+| builtin | __doc__ | documentation string | |
++-----------+-----------------+---------------------------+-------+
+| | __name__ | original name of this | |
+| | | function or method | |
++-----------+-----------------+---------------------------+-------+
+| | __self__ | instance to which a | |
+| | | method is bound, or | |
+| | | ``None`` | |
++-----------+-----------------+---------------------------+-------+
+
+Note:
+
+(1)
+ .. versionchanged:: 2.2
+ :attr:`im_class` used to refer to the class that defined the method.
+
+
+.. function:: getmembers(object[, predicate])
+
+ Return all the members of an object in a list of (name, value) pairs sorted by
+ name. If the optional *predicate* argument is supplied, only members for which
+ the predicate returns a true value are included.
+
+
+.. function:: getmoduleinfo(path)
+
+ Return a tuple of values that describe how Python will interpret the file
+ identified by *path* if it is a module, or ``None`` if it would not be
+ identified as a module. The return tuple is ``(name, suffix, mode, mtype)``,
+ where *name* is the name of the module without the name of any enclosing
+ package, *suffix* is the trailing part of the file name (which may not be a
+ dot-delimited extension), *mode* is the :func:`open` mode that would be used
+ (``'r'`` or ``'rb'``), and *mtype* is an integer giving the type of the
+ module. *mtype* will have a value which can be compared to the constants
+ defined in the :mod:`imp` module; see the documentation for that module for
+ more information on module types.
+
+
+.. function:: getmodulename(path)
+
+ Return the name of the module named by the file *path*, without including the
+ names of enclosing packages. This uses the same algorithm as the interpreter
+ uses when searching for modules. If the name cannot be matched according to the
+ interpreter's rules, ``None`` is returned.
+
+
+.. function:: ismodule(object)
+
+ Return true if the object is a module.
+
+
+.. function:: isclass(object)
+
+ Return true if the object is a class.
+
+
+.. function:: ismethod(object)
+
+ Return true if the object is a method.
+
+
+.. function:: isfunction(object)
+
+ Return true if the object is a Python function or unnamed (lambda) function.
+
+
+.. function:: istraceback(object)
+
+ Return true if the object is a traceback.
+
+
+.. function:: isframe(object)
+
+ Return true if the object is a frame.
+
+
+.. function:: iscode(object)
+
+ Return true if the object is a code.
+
+
+.. function:: isbuiltin(object)
+
+ Return true if the object is a built-in function.
+
+
+.. function:: isroutine(object)
+
+ Return true if the object is a user-defined or built-in function or method.
+
+
+.. function:: ismethoddescriptor(object)
+
+ Return true if the object is a method descriptor, but not if ismethod() or
+ isclass() or isfunction() are true.
+
+ This is new as of Python 2.2, and, for example, is true of int.__add__. An
+ object passing this test has a __get__ attribute but not a __set__ attribute,
+ but beyond that the set of attributes varies. __name__ is usually sensible, and
+ __doc__ often is.
+
+ Methods implemented via descriptors that also pass one of the other tests return
+ false from the ismethoddescriptor() test, simply because the other tests promise
+ more -- you can, e.g., count on having the im_func attribute (etc) when an
+ object passes ismethod().
+
+
+.. function:: isdatadescriptor(object)
+
+ Return true if the object is a data descriptor.
+
+ Data descriptors have both a __get__ and a __set__ attribute. Examples are
+ properties (defined in Python), getsets, and members. The latter two are
+ defined in C and there are more specific tests available for those types, which
+ is robust across Python implementations. Typically, data descriptors will also
+ have __name__ and __doc__ attributes (properties, getsets, and members have both
+ of these attributes), but this is not guaranteed.
+
+ .. versionadded:: 2.3
+
+
+.. function:: isgetsetdescriptor(object)
+
+ Return true if the object is a getset descriptor.
+
+ getsets are attributes defined in extension modules via ``PyGetSetDef``
+ structures. For Python implementations without such types, this method will
+ always return ``False``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: ismemberdescriptor(object)
+
+ Return true if the object is a member descriptor.
+
+ Member descriptors are attributes defined in extension modules via
+ ``PyMemberDef`` structures. For Python implementations without such types, this
+ method will always return ``False``.
+
+ .. versionadded:: 2.5
+
+
+.. _inspect-source:
+
+Retrieving source code
+----------------------
+
+
+.. function:: getdoc(object)
+
+ Get the documentation string for an object. All tabs are expanded to spaces. To
+ clean up docstrings that are indented to line up with blocks of code, any
+ whitespace than can be uniformly removed from the second line onwards is
+ removed.
+
+
+.. function:: getcomments(object)
+
+ Return in a single string any lines of comments immediately preceding the
+ object's source code (for a class, function, or method), or at the top of the
+ Python source file (if the object is a module).
+
+
+.. function:: getfile(object)
+
+ Return the name of the (text or binary) file in which an object was defined.
+ This will fail with a :exc:`TypeError` if the object is a built-in module,
+ class, or function.
+
+
+.. function:: getmodule(object)
+
+ Try to guess which module an object was defined in.
+
+
+.. function:: getsourcefile(object)
+
+ Return the name of the Python source file in which an object was defined. This
+ will fail with a :exc:`TypeError` if the object is a built-in module, class, or
+ function.
+
+
+.. function:: getsourcelines(object)
+
+ Return a list of source lines and starting line number for an object. The
+ argument may be a module, class, method, function, traceback, frame, or code
+ object. The source code is returned as a list of the lines corresponding to the
+ object and the line number indicates where in the original source file the first
+ line of code was found. An :exc:`IOError` is raised if the source code cannot
+ be retrieved.
+
+
+.. function:: getsource(object)
+
+ Return the text of the source code for an object. The argument may be a module,
+ class, method, function, traceback, frame, or code object. The source code is
+ returned as a single string. An :exc:`IOError` is raised if the source code
+ cannot be retrieved.
+
+
+.. _inspect-classes-functions:
+
+Classes and functions
+---------------------
+
+
+.. function:: getclasstree(classes[, unique])
+
+ Arrange the given list of classes into a hierarchy of nested lists. Where a
+ nested list appears, it contains classes derived from the class whose entry
+ immediately precedes the list. Each entry is a 2-tuple containing a class and a
+ tuple of its base classes. If the *unique* argument is true, exactly one entry
+ appears in the returned structure for each class in the given list. Otherwise,
+ classes using multiple inheritance and their descendants will appear multiple
+ times.
+
+
+.. function:: getargspec(func)
+
+ Get the names and default values of a function's arguments. A tuple of four
+ things is returned: ``(args, varargs, varkw, defaults)``. *args* is a list of
+ the argument names (it may contain nested lists). *varargs* and *varkw* are the
+ names of the ``*`` and ``**`` arguments or ``None``. *defaults* is a tuple of
+ default argument values or None if there are no default arguments; if this tuple
+ has *n* elements, they correspond to the last *n* elements listed in *args*.
+
+
+.. function:: getargvalues(frame)
+
+ Get information about arguments passed into a particular frame. A tuple of four
+ things is returned: ``(args, varargs, varkw, locals)``. *args* is a list of the
+ argument names (it may contain nested lists). *varargs* and *varkw* are the
+ names of the ``*`` and ``**`` arguments or ``None``. *locals* is the locals
+ dictionary of the given frame.
+
+
+.. function:: formatargspec(args[, varargs, varkw, defaults, formatarg, formatvarargs, formatvarkw, formatvalue, join])
+
+ Format a pretty argument spec from the four values returned by
+ :func:`getargspec`. The format\* arguments are the corresponding optional
+ formatting functions that are called to turn names and values into strings.
+
+
+.. function:: formatargvalues(args[, varargs, varkw, locals, formatarg, formatvarargs, formatvarkw, formatvalue, join])
+
+ Format a pretty argument spec from the four values returned by
+ :func:`getargvalues`. The format\* arguments are the corresponding optional
+ formatting functions that are called to turn names and values into strings.
+
+
+.. function:: getmro(cls)
+
+ Return a tuple of class cls's base classes, including cls, in method resolution
+ order. No class appears more than once in this tuple. Note that the method
+ resolution order depends on cls's type. Unless a very peculiar user-defined
+ metatype is in use, cls will be the first element of the tuple.
+
+
+.. _inspect-stack:
+
+The interpreter stack
+---------------------
+
+When the following functions return "frame records," each record is a tuple of
+six items: the frame object, the filename, the line number of the current line,
+the function name, a list of lines of context from the source code, and the
+index of the current line within that list.
+
+.. warning::
+
+ Keeping references to frame objects, as found in the first element of the frame
+ records these functions return, can cause your program to create reference
+ cycles. Once a reference cycle has been created, the lifespan of all objects
+ which can be accessed from the objects which form the cycle can become much
+ longer even if Python's optional cycle detector is enabled. If such cycles must
+ be created, it is important to ensure they are explicitly broken to avoid the
+ delayed destruction of objects and increased memory consumption which occurs.
+
+ Though the cycle detector will catch these, destruction of the frames (and local
+ variables) can be made deterministic by removing the cycle in a
+ :keyword:`finally` clause. This is also important if the cycle detector was
+ disabled when Python was compiled or using :func:`gc.disable`. For example::
+
+ def handle_stackframe_without_leak():
+ frame = inspect.currentframe()
+ try:
+ # do something with the frame
+ finally:
+ del frame
+
+The optional *context* argument supported by most of these functions specifies
+the number of lines of context to return, which are centered around the current
+line.
+
+
+.. function:: getframeinfo(frame[, context])
+
+ Get information about a frame or traceback object. A 5-tuple is returned, the
+ last five elements of the frame's frame record.
+
+
+.. function:: getouterframes(frame[, context])
+
+ Get a list of frame records for a frame and all outer frames. These frames
+ represent the calls that lead to the creation of *frame*. The first entry in the
+ returned list represents *frame*; the last entry represents the outermost call
+ on *frame*'s stack.
+
+
+.. function:: getinnerframes(traceback[, context])
+
+ Get a list of frame records for a traceback's frame and all inner frames. These
+ frames represent calls made as a consequence of *frame*. The first entry in the
+ list represents *traceback*; the last entry represents where the exception was
+ raised.
+
+
+.. function:: currentframe()
+
+ Return the frame object for the caller's stack frame.
+
+
+.. function:: stack([context])
+
+ Return a list of frame records for the caller's stack. The first entry in the
+ returned list represents the caller; the last entry represents the outermost
+ call on the stack.
+
+
+.. function:: trace([context])
+
+ Return a list of frame records for the stack between the current frame and the
+ frame in which an exception currently being handled was raised in. The first
+ entry in the list represents the caller; the last entry represents where the
+ exception was raised.
+
diff --git a/Doc/library/internet.rst b/Doc/library/internet.rst
new file mode 100644
index 0000000000..16b0a446a8
--- /dev/null
+++ b/Doc/library/internet.rst
@@ -0,0 +1,47 @@
+
+.. _internet:
+
+******************************
+Internet Protocols and Support
+******************************
+
+.. index::
+ single: WWW
+ single: Internet
+ single: World Wide Web
+
+.. index:: module: socket
+
+The modules described in this chapter implement Internet protocols and support
+for related technology. They are all implemented in Python. Most of these
+modules require the presence of the system-dependent module :mod:`socket`, which
+is currently supported on most popular platforms. Here is an overview:
+
+
+.. toctree::
+
+ webbrowser.rst
+ cgi.rst
+ cgitb.rst
+ wsgiref.rst
+ urllib.rst
+ urllib2.rst
+ httplib.rst
+ ftplib.rst
+ poplib.rst
+ imaplib.rst
+ nntplib.rst
+ smtplib.rst
+ smtpd.rst
+ telnetlib.rst
+ uuid.rst
+ urlparse.rst
+ socketserver.rst
+ basehttpserver.rst
+ simplehttpserver.rst
+ cgihttpserver.rst
+ cookielib.rst
+ cookie.rst
+ xmlrpclib.rst
+ simplexmlrpcserver.rst
+ docxmlrpcserver.rst
diff --git a/Doc/library/intro.rst b/Doc/library/intro.rst
new file mode 100644
index 0000000000..33bdefd72e
--- /dev/null
+++ b/Doc/library/intro.rst
@@ -0,0 +1,51 @@
+
+.. _library-intro:
+
+************
+Introduction
+************
+
+The "Python library" contains several different kinds of components.
+
+It contains data types that would normally be considered part of the "core" of a
+language, such as numbers and lists. For these types, the Python language core
+defines the form of literals and places some constraints on their semantics, but
+does not fully define the semantics. (On the other hand, the language core does
+define syntactic properties like the spelling and priorities of operators.)
+
+The library also contains built-in functions and exceptions --- objects that can
+be used by all Python code without the need of an :keyword:`import` statement.
+Some of these are defined by the core language, but many are not essential for
+the core semantics and are only described here.
+
+The bulk of the library, however, consists of a collection of modules. There are
+many ways to dissect this collection. Some modules are written in C and built
+in to the Python interpreter; others are written in Python and imported in
+source form. Some modules provide interfaces that are highly specific to
+Python, like printing a stack trace; some provide interfaces that are specific
+to particular operating systems, such as access to specific hardware; others
+provide interfaces that are specific to a particular application domain, like
+the World Wide Web. Some modules are available in all versions and ports of
+Python; others are only available when the underlying system supports or
+requires them; yet others are available only when a particular configuration
+option was chosen at the time when Python was compiled and installed.
+
+This manual is organized "from the inside out:" it first describes the built-in
+data types, then the built-in functions and exceptions, and finally the modules,
+grouped in chapters of related modules. The ordering of the chapters as well as
+the ordering of the modules within each chapter is roughly from most relevant to
+least important.
+
+This means that if you start reading this manual from the start, and skip to the
+next chapter when you get bored, you will get a reasonable overview of the
+available modules and application areas that are supported by the Python
+library. Of course, you don't *have* to read it like a novel --- you can also
+browse the table of contents (in front of the manual), or look for a specific
+function, module or term in the index (in the back). And finally, if you enjoy
+learning about random subjects, you choose a random page number (see module
+:mod:`random`) and read a section or two. Regardless of the order in which you
+read the sections of this manual, it helps to start with chapter :ref:`builtin`,
+as the remainder of the manual assumes familiarity with this material.
+
+Let the show begin!
+
diff --git a/Doc/library/ipc.rst b/Doc/library/ipc.rst
new file mode 100644
index 0000000000..fd425ed1f9
--- /dev/null
+++ b/Doc/library/ipc.rst
@@ -0,0 +1,24 @@
+
+.. _ipc:
+
+*****************************************
+Interprocess Communication and Networking
+*****************************************
+
+The modules described in this chapter provide mechanisms for different processes
+to communicate.
+
+Some modules only work for two processes that are on the same machine, e.g.
+:mod:`signal` and :mod:`subprocess`. Other modules support networking protocols
+that two or more processes can used to communicate across machines.
+
+The list of modules described in this chapter is:
+
+
+.. toctree::
+
+ subprocess.rst
+ socket.rst
+ signal.rst
+ asyncore.rst
+ asynchat.rst
diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
new file mode 100644
index 0000000000..9f9cb24864
--- /dev/null
+++ b/Doc/library/itertools.rst
@@ -0,0 +1,547 @@
+
+:mod:`itertools` --- Functions creating iterators for efficient looping
+=======================================================================
+
+.. module:: itertools
+ :synopsis: Functions creating iterators for efficient looping.
+.. moduleauthor:: Raymond Hettinger <python@rcn.com>
+.. sectionauthor:: Raymond Hettinger <python@rcn.com>
+
+
+.. versionadded:: 2.3
+
+This module implements a number of iterator building blocks inspired by
+constructs from the Haskell and SML programming languages. Each has been recast
+in a form suitable for Python.
+
+The module standardizes a core set of fast, memory efficient tools that are
+useful by themselves or in combination. Standardization helps avoid the
+readability and reliability problems which arise when many different individuals
+create their own slightly varying implementations, each with their own quirks
+and naming conventions.
+
+The tools are designed to combine readily with one another. This makes it easy
+to construct more specialized tools succinctly and efficiently in pure Python.
+
+For instance, SML provides a tabulation tool: ``tabulate(f)`` which produces a
+sequence ``f(0), f(1), ...``. This toolbox provides :func:`imap` and
+:func:`count` which can be combined to form ``imap(f, count())`` and produce an
+equivalent result.
+
+Likewise, the functional tools are designed to work well with the high-speed
+functions provided by the :mod:`operator` module.
+
+The module author welcomes suggestions for other basic building blocks to be
+added to future versions of the module.
+
+Whether cast in pure python form or compiled code, tools that use iterators are
+more memory efficient (and faster) than their list based counterparts. Adopting
+the principles of just-in-time manufacturing, they create data when and where
+needed instead of consuming memory with the computer equivalent of "inventory".
+
+The performance advantage of iterators becomes more acute as the number of
+elements increases -- at some point, lists grow large enough to severely impact
+memory cache performance and start running slowly.
+
+
+.. seealso::
+
+ The Standard ML Basis Library, `The Standard ML Basis Library
+ <http://www.standardml.org/Basis/>`_.
+
+ Haskell, A Purely Functional Language, `Definition of Haskell and the Standard
+ Libraries <http://www.haskell.org/definition/>`_.
+
+
+.. _itertools-functions:
+
+Itertool functions
+------------------
+
+The following module functions all construct and return iterators. Some provide
+streams of infinite length, so they should only be accessed by functions or
+loops that truncate the stream.
+
+
+.. function:: chain(*iterables)
+
+ Make an iterator that returns elements from the first iterable until it is
+ exhausted, then proceeds to the next iterable, until all of the iterables are
+ exhausted. Used for treating consecutive sequences as a single sequence.
+ Equivalent to::
+
+ def chain(*iterables):
+ for it in iterables:
+ for element in it:
+ yield element
+
+
+.. function:: count([n])
+
+ Make an iterator that returns consecutive integers starting with *n*. If not
+ specified *n* defaults to zero. Does not currently support python long
+ integers. Often used as an argument to :func:`imap` to generate consecutive
+ data points. Also, used with :func:`izip` to add sequence numbers. Equivalent
+ to::
+
+ def count(n=0):
+ while True:
+ yield n
+ n += 1
+
+ Note, :func:`count` does not check for overflow and will return negative numbers
+ after exceeding ``sys.maxint``. This behavior may change in the future.
+
+
+.. function:: cycle(iterable)
+
+ Make an iterator returning elements from the iterable and saving a copy of each.
+ When the iterable is exhausted, return elements from the saved copy. Repeats
+ indefinitely. Equivalent to::
+
+ def cycle(iterable):
+ saved = []
+ for element in iterable:
+ yield element
+ saved.append(element)
+ while saved:
+ for element in saved:
+ yield element
+
+ Note, this member of the toolkit may require significant auxiliary storage
+ (depending on the length of the iterable).
+
+
+.. function:: dropwhile(predicate, iterable)
+
+ Make an iterator that drops elements from the iterable as long as the predicate
+ is true; afterwards, returns every element. Note, the iterator does not produce
+ *any* output until the predicate first becomes false, so it may have a lengthy
+ start-up time. Equivalent to::
+
+ def dropwhile(predicate, iterable):
+ iterable = iter(iterable)
+ for x in iterable:
+ if not predicate(x):
+ yield x
+ break
+ for x in iterable:
+ yield x
+
+
+.. function:: groupby(iterable[, key])
+
+ Make an iterator that returns consecutive keys and groups from the *iterable*.
+ The *key* is a function computing a key value for each element. If not
+ specified or is ``None``, *key* defaults to an identity function and returns
+ the element unchanged. Generally, the iterable needs to already be sorted on
+ the same key function.
+
+ The operation of :func:`groupby` is similar to the ``uniq`` filter in Unix. It
+ generates a break or new group every time the value of the key function changes
+ (which is why it is usually necessary to have sorted the data using the same key
+ function). That behavior differs from SQL's GROUP BY which aggregates common
+ elements regardless of their input order.
+
+ The returned group is itself an iterator that shares the underlying iterable
+ with :func:`groupby`. Because the source is shared, when the :func:`groupby`
+ object is advanced, the previous group is no longer visible. So, if that data
+ is needed later, it should be stored as a list::
+
+ groups = []
+ uniquekeys = []
+ data = sorted(data, key=keyfunc)
+ for k, g in groupby(data, keyfunc):
+ groups.append(list(g)) # Store group iterator as a list
+ uniquekeys.append(k)
+
+ :func:`groupby` is equivalent to::
+
+ class groupby(object):
+ def __init__(self, iterable, key=None):
+ if key is None:
+ key = lambda x: x
+ self.keyfunc = key
+ self.it = iter(iterable)
+ self.tgtkey = self.currkey = self.currvalue = []
+ def __iter__(self):
+ return self
+ def __next__(self):
+ while self.currkey == self.tgtkey:
+ self.currvalue = next(self.it) # Exit on StopIteration
+ self.currkey = self.keyfunc(self.currvalue)
+ self.tgtkey = self.currkey
+ return (self.currkey, self._grouper(self.tgtkey))
+ def _grouper(self, tgtkey):
+ while self.currkey == tgtkey:
+ yield self.currvalue
+ self.currvalue = next(self.it) # Exit on StopIteration
+ self.currkey = self.keyfunc(self.currvalue)
+
+ .. versionadded:: 2.4
+
+
+.. function:: ifilter(predicate, iterable)
+
+ Make an iterator that filters elements from iterable returning only those for
+ which the predicate is ``True``. If *predicate* is ``None``, return the items
+ that are true. Equivalent to::
+
+ def ifilter(predicate, iterable):
+ if predicate is None:
+ predicate = bool
+ for x in iterable:
+ if predicate(x):
+ yield x
+
+
+.. function:: ifilterfalse(predicate, iterable)
+
+ Make an iterator that filters elements from iterable returning only those for
+ which the predicate is ``False``. If *predicate* is ``None``, return the items
+ that are false. Equivalent to::
+
+ def ifilterfalse(predicate, iterable):
+ if predicate is None:
+ predicate = bool
+ for x in iterable:
+ if not predicate(x):
+ yield x
+
+
+.. function:: imap(function, *iterables)
+
+ Make an iterator that computes the function using arguments from each of the
+ iterables. If *function* is set to ``None``, then :func:`imap` returns the
+ arguments as a tuple. Like :func:`map` but stops when the shortest iterable is
+ exhausted instead of filling in ``None`` for shorter iterables. The reason for
+ the difference is that infinite iterator arguments are typically an error for
+ :func:`map` (because the output is fully evaluated) but represent a common and
+ useful way of supplying arguments to :func:`imap`. Equivalent to::
+
+ def imap(function, *iterables):
+ iterables = map(iter, iterables)
+ while True:
+ args = [next(i) for i in iterables]
+ if function is None:
+ yield tuple(args)
+ else:
+ yield function(*args)
+
+
+.. function:: islice(iterable, [start,] stop [, step])
+
+ Make an iterator that returns selected elements from the iterable. If *start* is
+ non-zero, then elements from the iterable are skipped until start is reached.
+ Afterward, elements are returned consecutively unless *step* is set higher than
+ one which results in items being skipped. If *stop* is ``None``, then iteration
+ continues until the iterator is exhausted, if at all; otherwise, it stops at the
+ specified position. Unlike regular slicing, :func:`islice` does not support
+ negative values for *start*, *stop*, or *step*. Can be used to extract related
+ fields from data where the internal structure has been flattened (for example, a
+ multi-line report may list a name field on every third line). Equivalent to::
+
+ def islice(iterable, *args):
+ s = slice(*args)
+ it = iter(range(s.start or 0, s.stop or sys.maxint, s.step or 1))
+ nexti = next(it)
+ for i, element in enumerate(iterable):
+ if i == nexti:
+ yield element
+ nexti = next(it)
+
+ If *start* is ``None``, then iteration starts at zero. If *step* is ``None``,
+ then the step defaults to one.
+
+ .. versionchanged:: 2.5
+ accept ``None`` values for default *start* and *step*.
+
+
+.. function:: izip(*iterables)
+
+ Make an iterator that aggregates elements from each of the iterables. Like
+ :func:`zip` except that it returns an iterator instead of a list. Used for
+ lock-step iteration over several iterables at a time. Equivalent to::
+
+ def izip(*iterables):
+ iterables = map(iter, iterables)
+ while iterables:
+ result = [next(it) for it in iterables]
+ yield tuple(result)
+
+ .. versionchanged:: 2.4
+ When no iterables are specified, returns a zero length iterator instead of
+ raising a :exc:`TypeError` exception.
+
+ Note, the left-to-right evaluation order of the iterables is guaranteed. This
+ makes possible an idiom for clustering a data series into n-length groups using
+ ``izip(*[iter(s)]*n)``. For data that doesn't fit n-length groups exactly, the
+ last tuple can be pre-padded with fill values using ``izip(*[chain(s,
+ [None]*(n-1))]*n)``.
+
+ Note, when :func:`izip` is used with unequal length inputs, subsequent
+ iteration over the longer iterables cannot reliably be continued after
+ :func:`izip` terminates. Potentially, up to one entry will be missing from
+ each of the left-over iterables. This occurs because a value is fetched from
+ each iterator in- turn, but the process ends when one of the iterators
+ terminates. This leaves the last fetched values in limbo (they cannot be
+ returned in a final, incomplete tuple and they are cannot be pushed back into
+ the iterator for retrieval with ``next(it)``). In general, :func:`izip`
+ should only be used with unequal length inputs when you don't care about
+ trailing, unmatched values from the longer iterables.
+
+
+.. function:: izip_longest(*iterables[, fillvalue])
+
+ Make an iterator that aggregates elements from each of the iterables. If the
+ iterables are of uneven length, missing values are filled-in with *fillvalue*.
+ Iteration continues until the longest iterable is exhausted. Equivalent to::
+
+ def izip_longest(*args, **kwds):
+ fillvalue = kwds.get('fillvalue')
+ def sentinel(counter = ([fillvalue]*(len(args)-1)).pop):
+ yield counter() # yields the fillvalue, or raises IndexError
+ fillers = repeat(fillvalue)
+ iters = [chain(it, sentinel(), fillers) for it in args]
+ try:
+ for tup in izip(*iters):
+ yield tup
+ except IndexError:
+ pass
+
+ If one of the iterables is potentially infinite, then the :func:`izip_longest`
+ function should be wrapped with something that limits the number of calls (for
+ example :func:`islice` or :func:`takewhile`).
+
+ .. versionadded:: 2.6
+
+
+.. function:: repeat(object[, times])
+
+ Make an iterator that returns *object* over and over again. Runs indefinitely
+ unless the *times* argument is specified. Used as argument to :func:`imap` for
+ invariant parameters to the called function. Also used with :func:`izip` to
+ create an invariant part of a tuple record. Equivalent to::
+
+ def repeat(object, times=None):
+ if times is None:
+ while True:
+ yield object
+ else:
+ for i in range(times):
+ yield object
+
+
+.. function:: starmap(function, iterable)
+
+ Make an iterator that computes the function using arguments tuples obtained from
+ the iterable. Used instead of :func:`imap` when argument parameters are already
+ grouped in tuples from a single iterable (the data has been "pre-zipped"). The
+ difference between :func:`imap` and :func:`starmap` parallels the distinction
+ between ``function(a,b)`` and ``function(*c)``. Equivalent to::
+
+ def starmap(function, iterable):
+ iterable = iter(iterable)
+ while True:
+ yield function(*next(iterable))
+
+
+.. function:: takewhile(predicate, iterable)
+
+ Make an iterator that returns elements from the iterable as long as the
+ predicate is true. Equivalent to::
+
+ def takewhile(predicate, iterable):
+ for x in iterable:
+ if predicate(x):
+ yield x
+ else:
+ break
+
+
+.. function:: tee(iterable[, n=2])
+
+ Return *n* independent iterators from a single iterable. The case where ``n==2``
+ is equivalent to::
+
+ def tee(iterable):
+ def gen(next, data={}, cnt=[0]):
+ for i in count():
+ if i == cnt[0]:
+ item = data[i] = next()
+ cnt[0] += 1
+ else:
+ item = data.pop(i)
+ yield item
+ it = iter(iterable)
+ return (gen(it.__next__), gen(it.__next__))
+
+ Note, once :func:`tee` has made a split, the original *iterable* should not be
+ used anywhere else; otherwise, the *iterable* could get advanced without the tee
+ objects being informed.
+
+ Note, this member of the toolkit may require significant auxiliary storage
+ (depending on how much temporary data needs to be stored). In general, if one
+ iterator is going to use most or all of the data before the other iterator, it
+ is faster to use :func:`list` instead of :func:`tee`.
+
+ .. versionadded:: 2.4
+
+
+.. _itertools-example:
+
+Examples
+--------
+
+The following examples show common uses for each tool and demonstrate ways they
+can be combined. ::
+
+ >>> amounts = [120.15, 764.05, 823.14]
+ >>> for checknum, amount in izip(count(1200), amounts):
+ ... print 'Check %d is for $%.2f' % (checknum, amount)
+ ...
+ Check 1200 is for $120.15
+ Check 1201 is for $764.05
+ Check 1202 is for $823.14
+
+ >>> import operator
+ >>> for cube in imap(operator.pow, range(1,5), repeat(3)):
+ ... print cube
+ ...
+ 1
+ 8
+ 27
+ 64
+
+ >>> reportlines = ['EuroPython', 'Roster', '', 'alex', '', 'laura',
+ ... '', 'martin', '', 'walter', '', 'mark']
+ >>> for name in islice(reportlines, 3, None, 2):
+ ... print name.title()
+ ...
+ Alex
+ Laura
+ Martin
+ Walter
+ Mark
+
+ # Show a dictionary sorted and grouped by value
+ >>> from operator import itemgetter
+ >>> d = dict(a=1, b=2, c=1, d=2, e=1, f=2, g=3)
+ >>> di = sorted(d.iteritems(), key=itemgetter(1))
+ >>> for k, g in groupby(di, key=itemgetter(1)):
+ ... print k, map(itemgetter(0), g)
+ ...
+ 1 ['a', 'c', 'e']
+ 2 ['b', 'd', 'f']
+ 3 ['g']
+
+ # Find runs of consecutive numbers using groupby. The key to the solution
+ # is differencing with a range so that consecutive numbers all appear in
+ # same group.
+ >>> data = [ 1, 4,5,6, 10, 15,16,17,18, 22, 25,26,27,28]
+ >>> for k, g in groupby(enumerate(data), lambda t:t[0]-t[1]):
+ ... print map(operator.itemgetter(1), g)
+ ...
+ [1]
+ [4, 5, 6]
+ [10]
+ [15, 16, 17, 18]
+ [22]
+ [25, 26, 27, 28]
+
+
+
+.. _itertools-recipes:
+
+Recipes
+-------
+
+This section shows recipes for creating an extended toolset using the existing
+itertools as building blocks.
+
+The extended tools offer the same high performance as the underlying toolset.
+The superior memory performance is kept by processing elements one at a time
+rather than bringing the whole iterable into memory all at once. Code volume is
+kept small by linking the tools together in a functional style which helps
+eliminate temporary variables. High speed is retained by preferring
+"vectorized" building blocks over the use of for-loops and generators which
+incur interpreter overhead. ::
+
+ def take(n, seq):
+ return list(islice(seq, n))
+
+ def enumerate(iterable):
+ return izip(count(), iterable)
+
+ def tabulate(function):
+ "Return function(0), function(1), ..."
+ return imap(function, count())
+
+ def iteritems(mapping):
+ return izip(mapping.iterkeys(), mapping.itervalues())
+
+ def nth(iterable, n):
+ "Returns the nth item or raise StopIteration"
+ return islice(iterable, n, None).next()
+
+ def all(seq, pred=None):
+ "Returns True if pred(x) is true for every element in the iterable"
+ for elem in ifilterfalse(pred, seq):
+ return False
+ return True
+
+ def any(seq, pred=None):
+ "Returns True if pred(x) is true for at least one element in the iterable"
+ for elem in ifilter(pred, seq):
+ return True
+ return False
+
+ def no(seq, pred=None):
+ "Returns True if pred(x) is false for every element in the iterable"
+ for elem in ifilter(pred, seq):
+ return False
+ return True
+
+ def quantify(seq, pred=None):
+ "Count how many times the predicate is true in the sequence"
+ return sum(imap(pred, seq))
+
+ def padnone(seq):
+ """Returns the sequence elements and then returns None indefinitely.
+
+ Useful for emulating the behavior of the built-in map() function.
+ """
+ return chain(seq, repeat(None))
+
+ def ncycles(seq, n):
+ "Returns the sequence elements n times"
+ return chain(*repeat(seq, n))
+
+ def dotproduct(vec1, vec2):
+ return sum(imap(operator.mul, vec1, vec2))
+
+ def flatten(listOfLists):
+ return list(chain(*listOfLists))
+
+ def repeatfunc(func, times=None, *args):
+ """Repeat calls to func with specified arguments.
+
+ Example: repeatfunc(random.random)
+ """
+ if times is None:
+ return starmap(func, repeat(args))
+ else:
+ return starmap(func, repeat(args, times))
+
+ def pairwise(iterable):
+ "s -> (s0,s1), (s1,s2), (s2, s3), ..."
+ a, b = tee(iterable)
+ next(b, None)
+ return izip(a, b)
+
+ def grouper(n, iterable, padvalue=None):
+ "grouper(3, 'abcdefg', 'x') --> ('a','b','c'), ('d','e','f'), ('g','x','x')"
+ return izip(*[chain(iterable, repeat(padvalue, n-1))]*n)
+
+
+
diff --git a/Doc/library/keyword.rst b/Doc/library/keyword.rst
new file mode 100644
index 0000000000..32a2d347df
--- /dev/null
+++ b/Doc/library/keyword.rst
@@ -0,0 +1,22 @@
+
+:mod:`keyword` --- Testing for Python keywords
+==============================================
+
+.. module:: keyword
+ :synopsis: Test whether a string is a keyword in Python.
+
+
+This module allows a Python program to determine if a string is a keyword.
+
+
+.. function:: iskeyword(s)
+
+ Return true if *s* is a Python keyword.
+
+
+.. data:: kwlist
+
+ Sequence containing all the keywords defined for the interpreter. If any
+ keywords are defined to only be active when particular :mod:`__future__`
+ statements are in effect, these will be included as well.
+
diff --git a/Doc/library/language.rst b/Doc/library/language.rst
new file mode 100644
index 0000000000..7d6af7deff
--- /dev/null
+++ b/Doc/library/language.rst
@@ -0,0 +1,29 @@
+
+.. _language:
+
+************************
+Python Language Services
+************************
+
+Python provides a number of modules to assist in working with the Python
+language. These modules support tokenizing, parsing, syntax analysis, bytecode
+disassembly, and various other facilities.
+
+These modules include:
+
+
+.. toctree::
+
+ parser.rst
+ _ast.rst
+ symbol.rst
+ token.rst
+ keyword.rst
+ tokenize.rst
+ tabnanny.rst
+ pyclbr.rst
+ py_compile.rst
+ compileall.rst
+ dis.rst
+ pickletools.rst
+ distutils.rst
diff --git a/Doc/library/linecache.rst b/Doc/library/linecache.rst
new file mode 100644
index 0000000000..f3d83799dc
--- /dev/null
+++ b/Doc/library/linecache.rst
@@ -0,0 +1,52 @@
+
+:mod:`linecache` --- Random access to text lines
+================================================
+
+.. module:: linecache
+ :synopsis: This module provides random access to individual lines from text files.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`linecache` module allows one to get any line from any file, while
+attempting to optimize internally, using a cache, the common case where many
+lines are read from a single file. This is used by the :mod:`traceback` module
+to retrieve source lines for inclusion in the formatted traceback.
+
+The :mod:`linecache` module defines the following functions:
+
+
+.. function:: getline(filename, lineno[, module_globals])
+
+ Get line *lineno* from file named *filename*. This function will never throw an
+ exception --- it will return ``''`` on errors (the terminating newline character
+ will be included for lines that are found).
+
+ .. index:: triple: module; search; path
+
+ If a file named *filename* is not found, the function will look for it in the
+ module search path, ``sys.path``, after first checking for a :pep:`302`
+ ``__loader__`` in *module_globals*, in case the module was imported from a
+ zipfile or other non-filesystem import source.
+
+ .. versionadded:: 2.5
+ The *module_globals* parameter was added.
+
+
+.. function:: clearcache()
+
+ Clear the cache. Use this function if you no longer need lines from files
+ previously read using :func:`getline`.
+
+
+.. function:: checkcache([filename])
+
+ Check the cache for validity. Use this function if files in the cache may have
+ changed on disk, and you require the updated version. If *filename* is omitted,
+ it will check all the entries in the cache.
+
+Example::
+
+ >>> import linecache
+ >>> linecache.getline('/etc/passwd', 4)
+ 'sys:x:3:3:sys:/dev:/bin/sh\n'
+
diff --git a/Doc/library/locale.rst b/Doc/library/locale.rst
new file mode 100644
index 0000000000..6d427b7dc6
--- /dev/null
+++ b/Doc/library/locale.rst
@@ -0,0 +1,578 @@
+
+:mod:`locale` --- Internationalization services
+===============================================
+
+.. module:: locale
+ :synopsis: Internationalization services.
+.. moduleauthor:: Martin von Löwis <martin@v.loewis.de>
+.. sectionauthor:: Martin von Löwis <martin@v.loewis.de>
+
+
+The :mod:`locale` module opens access to the POSIX locale database and
+functionality. The POSIX locale mechanism allows programmers to deal with
+certain cultural issues in an application, without requiring the programmer to
+know all the specifics of each country where the software is executed.
+
+.. index:: module: _locale
+
+The :mod:`locale` module is implemented on top of the :mod:`_locale` module,
+which in turn uses an ANSI C locale implementation if available.
+
+The :mod:`locale` module defines the following exception and functions:
+
+
+.. exception:: Error
+
+ Exception raised when :func:`setlocale` fails.
+
+
+.. function:: setlocale(category[, locale])
+
+ If *locale* is specified, it may be a string, a tuple of the form ``(language
+ code, encoding)``, or ``None``. If it is a tuple, it is converted to a string
+ using the locale aliasing engine. If *locale* is given and not ``None``,
+ :func:`setlocale` modifies the locale setting for the *category*. The available
+ categories are listed in the data description below. The value is the name of a
+ locale. An empty string specifies the user's default settings. If the
+ modification of the locale fails, the exception :exc:`Error` is raised. If
+ successful, the new locale setting is returned.
+
+ If *locale* is omitted or ``None``, the current setting for *category* is
+ returned.
+
+ :func:`setlocale` is not thread safe on most systems. Applications typically
+ start with a call of ::
+
+ import locale
+ locale.setlocale(locale.LC_ALL, '')
+
+ This sets the locale for all categories to the user's default setting (typically
+ specified in the :envvar:`LANG` environment variable). If the locale is not
+ changed thereafter, using multithreading should not cause problems.
+
+ .. versionchanged:: 2.0
+ Added support for tuple values of the *locale* parameter.
+
+
+.. function:: localeconv()
+
+ Returns the database of the local conventions as a dictionary. This dictionary
+ has the following strings as keys:
+
+ +----------------------+-------------------------------------+--------------------------------+
+ | Category | Key | Meaning |
+ +======================+=====================================+================================+
+ | :const:`LC_NUMERIC` | ``'decimal_point'`` | Decimal point character. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'grouping'`` | Sequence of numbers specifying |
+ | | | which relative positions the |
+ | | | ``'thousands_sep'`` is |
+ | | | expected. If the sequence is |
+ | | | terminated with |
+ | | | :const:`CHAR_MAX`, no further |
+ | | | grouping is performed. If the |
+ | | | sequence terminates with a |
+ | | | ``0``, the last group size is |
+ | | | repeatedly used. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'thousands_sep'`` | Character used between groups. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | :const:`LC_MONETARY` | ``'int_curr_symbol'`` | International currency symbol. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'currency_symbol'`` | Local currency symbol. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'p_cs_precedes/n_cs_precedes'`` | Whether the currency symbol |
+ | | | precedes the value (for |
+ | | | positive resp. negative |
+ | | | values). |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'p_sep_by_space/n_sep_by_space'`` | Whether the currency symbol is |
+ | | | separated from the value by a |
+ | | | space (for positive resp. |
+ | | | negative values). |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'mon_decimal_point'`` | Decimal point used for |
+ | | | monetary values. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'frac_digits'`` | Number of fractional digits |
+ | | | used in local formatting of |
+ | | | monetary values. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'int_frac_digits'`` | Number of fractional digits |
+ | | | used in international |
+ | | | formatting of monetary values. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'mon_thousands_sep'`` | Group separator used for |
+ | | | monetary values. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'mon_grouping'`` | Equivalent to ``'grouping'``, |
+ | | | used for monetary values. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'positive_sign'`` | Symbol used to annotate a |
+ | | | positive monetary value. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'negative_sign'`` | Symbol used to annotate a |
+ | | | negative monetary value. |
+ +----------------------+-------------------------------------+--------------------------------+
+ | | ``'p_sign_posn/n_sign_posn'`` | The position of the sign (for |
+ | | | positive resp. negative |
+ | | | values), see below. |
+ +----------------------+-------------------------------------+--------------------------------+
+
+ All numeric values can be set to :const:`CHAR_MAX` to indicate that there is no
+ value specified in this locale.
+
+ The possible values for ``'p_sign_posn'`` and ``'n_sign_posn'`` are given below.
+
+ +--------------+-----------------------------------------+
+ | Value | Explanation |
+ +==============+=========================================+
+ | ``0`` | Currency and value are surrounded by |
+ | | parentheses. |
+ +--------------+-----------------------------------------+
+ | ``1`` | The sign should precede the value and |
+ | | currency symbol. |
+ +--------------+-----------------------------------------+
+ | ``2`` | The sign should follow the value and |
+ | | currency symbol. |
+ +--------------+-----------------------------------------+
+ | ``3`` | The sign should immediately precede the |
+ | | value. |
+ +--------------+-----------------------------------------+
+ | ``4`` | The sign should immediately follow the |
+ | | value. |
+ +--------------+-----------------------------------------+
+ | ``CHAR_MAX`` | Nothing is specified in this locale. |
+ +--------------+-----------------------------------------+
+
+
+.. function:: nl_langinfo(option)
+
+ Return some locale-specific information as a string. This function is not
+ available on all systems, and the set of possible options might also vary across
+ platforms. The possible argument values are numbers, for which symbolic
+ constants are available in the locale module.
+
+
+.. function:: getdefaultlocale([envvars])
+
+ Tries to determine the default locale settings and returns them as a tuple of
+ the form ``(language code, encoding)``.
+
+ According to POSIX, a program which has not called ``setlocale(LC_ALL, '')``
+ runs using the portable ``'C'`` locale. Calling ``setlocale(LC_ALL, '')`` lets
+ it use the default locale as defined by the :envvar:`LANG` variable. Since we
+ do not want to interfere with the current locale setting we thus emulate the
+ behavior in the way described above.
+
+ To maintain compatibility with other platforms, not only the :envvar:`LANG`
+ variable is tested, but a list of variables given as envvars parameter. The
+ first found to be defined will be used. *envvars* defaults to the search path
+ used in GNU gettext; it must always contain the variable name ``LANG``. The GNU
+ gettext search path contains ``'LANGUAGE'``, ``'LC_ALL'``, ``'LC_CTYPE'``, and
+ ``'LANG'``, in that order.
+
+ Except for the code ``'C'``, the language code corresponds to :rfc:`1766`.
+ *language code* and *encoding* may be ``None`` if their values cannot be
+ determined.
+
+ .. versionadded:: 2.0
+
+
+.. function:: getlocale([category])
+
+ Returns the current setting for the given locale category as sequence containing
+ *language code*, *encoding*. *category* may be one of the :const:`LC_\*` values
+ except :const:`LC_ALL`. It defaults to :const:`LC_CTYPE`.
+
+ Except for the code ``'C'``, the language code corresponds to :rfc:`1766`.
+ *language code* and *encoding* may be ``None`` if their values cannot be
+ determined.
+
+ .. versionadded:: 2.0
+
+
+.. function:: getpreferredencoding([do_setlocale])
+
+ Return the encoding used for text data, according to user preferences. User
+ preferences are expressed differently on different systems, and might not be
+ available programmatically on some systems, so this function only returns a
+ guess.
+
+ On some systems, it is necessary to invoke :func:`setlocale` to obtain the user
+ preferences, so this function is not thread-safe. If invoking setlocale is not
+ necessary or desired, *do_setlocale* should be set to ``False``.
+
+ .. versionadded:: 2.3
+
+
+.. function:: normalize(localename)
+
+ Returns a normalized locale code for the given locale name. The returned locale
+ code is formatted for use with :func:`setlocale`. If normalization fails, the
+ original name is returned unchanged.
+
+ If the given encoding is not known, the function defaults to the default
+ encoding for the locale code just like :func:`setlocale`.
+
+ .. versionadded:: 2.0
+
+
+.. function:: resetlocale([category])
+
+ Sets the locale for *category* to the default setting.
+
+ The default setting is determined by calling :func:`getdefaultlocale`.
+ *category* defaults to :const:`LC_ALL`.
+
+ .. versionadded:: 2.0
+
+
+.. function:: strcoll(string1, string2)
+
+ Compares two strings according to the current :const:`LC_COLLATE` setting. As
+ any other compare function, returns a negative, or a positive value, or ``0``,
+ depending on whether *string1* collates before or after *string2* or is equal to
+ it.
+
+
+.. function:: strxfrm(string)
+
+ .. index:: builtin: cmp
+
+ Transforms a string to one that can be used for the built-in function
+ :func:`cmp`, and still returns locale-aware results. This function can be used
+ when the same string is compared repeatedly, e.g. when collating a sequence of
+ strings.
+
+
+.. function:: format(format, val[, grouping[, monetary]])
+
+ Formats a number *val* according to the current :const:`LC_NUMERIC` setting.
+ The format follows the conventions of the ``%`` operator. For floating point
+ values, the decimal point is modified if appropriate. If *grouping* is true,
+ also takes the grouping into account.
+
+ If *monetary* is true, the conversion uses monetary thousands separator and
+ grouping strings.
+
+ Please note that this function will only work for exactly one %char specifier.
+ For whole format strings, use :func:`format_string`.
+
+ .. versionchanged:: 2.5
+ Added the *monetary* parameter.
+
+
+.. function:: format_string(format, val[, grouping])
+
+ Processes formatting specifiers as in ``format % val``, but takes the current
+ locale settings into account.
+
+ .. versionadded:: 2.5
+
+
+.. function:: currency(val[, symbol[, grouping[, international]]])
+
+ Formats a number *val* according to the current :const:`LC_MONETARY` settings.
+
+ The returned string includes the currency symbol if *symbol* is true, which is
+ the default. If *grouping* is true (which is not the default), grouping is done
+ with the value. If *international* is true (which is not the default), the
+ international currency symbol is used.
+
+ Note that this function will not work with the 'C' locale, so you have to set a
+ locale via :func:`setlocale` first.
+
+ .. versionadded:: 2.5
+
+
+.. function:: str(float)
+
+ Formats a floating point number using the same format as the built-in function
+ ``str(float)``, but takes the decimal point into account.
+
+
+.. function:: atof(string)
+
+ Converts a string to a floating point number, following the :const:`LC_NUMERIC`
+ settings.
+
+
+.. function:: atoi(string)
+
+ Converts a string to an integer, following the :const:`LC_NUMERIC` conventions.
+
+
+.. data:: LC_CTYPE
+
+ .. index:: module: string
+
+ Locale category for the character type functions. Depending on the settings of
+ this category, the functions of module :mod:`string` dealing with case change
+ their behaviour.
+
+
+.. data:: LC_COLLATE
+
+ Locale category for sorting strings. The functions :func:`strcoll` and
+ :func:`strxfrm` of the :mod:`locale` module are affected.
+
+
+.. data:: LC_TIME
+
+ Locale category for the formatting of time. The function :func:`time.strftime`
+ follows these conventions.
+
+
+.. data:: LC_MONETARY
+
+ Locale category for formatting of monetary values. The available options are
+ available from the :func:`localeconv` function.
+
+
+.. data:: LC_MESSAGES
+
+ Locale category for message display. Python currently does not support
+ application specific locale-aware messages. Messages displayed by the operating
+ system, like those returned by :func:`os.strerror` might be affected by this
+ category.
+
+
+.. data:: LC_NUMERIC
+
+ Locale category for formatting numbers. The functions :func:`format`,
+ :func:`atoi`, :func:`atof` and :func:`str` of the :mod:`locale` module are
+ affected by that category. All other numeric formatting operations are not
+ affected.
+
+
+.. data:: LC_ALL
+
+ Combination of all locale settings. If this flag is used when the locale is
+ changed, setting the locale for all categories is attempted. If that fails for
+ any category, no category is changed at all. When the locale is retrieved using
+ this flag, a string indicating the setting for all categories is returned. This
+ string can be later used to restore the settings.
+
+
+.. data:: CHAR_MAX
+
+ This is a symbolic constant used for different values returned by
+ :func:`localeconv`.
+
+The :func:`nl_langinfo` function accepts one of the following keys. Most
+descriptions are taken from the corresponding description in the GNU C library.
+
+
+.. data:: CODESET
+
+ Return a string with the name of the character encoding used in the selected
+ locale.
+
+
+.. data:: D_T_FMT
+
+ Return a string that can be used as a format string for strftime(3) to represent
+ time and date in a locale-specific way.
+
+
+.. data:: D_FMT
+
+ Return a string that can be used as a format string for strftime(3) to represent
+ a date in a locale-specific way.
+
+
+.. data:: T_FMT
+
+ Return a string that can be used as a format string for strftime(3) to represent
+ a time in a locale-specific way.
+
+
+.. data:: T_FMT_AMPM
+
+ The return value can be used as a format string for 'strftime' to represent time
+ in the am/pm format.
+
+
+.. data:: DAY_1 ... DAY_7
+
+ Return name of the n-th day of the week.
+
+ .. warning::
+
+ This follows the US convention of :const:`DAY_1` being Sunday, not the
+ international convention (ISO 8601) that Monday is the first day of the week.
+
+
+.. data:: ABDAY_1 ... ABDAY_7
+
+ Return abbreviated name of the n-th day of the week.
+
+
+.. data:: MON_1 ... MON_12
+
+ Return name of the n-th month.
+
+
+.. data:: ABMON_1 ... ABMON_12
+
+ Return abbreviated name of the n-th month.
+
+
+.. data:: RADIXCHAR
+
+ Return radix character (decimal dot, decimal comma, etc.)
+
+
+.. data:: THOUSEP
+
+ Return separator character for thousands (groups of three digits).
+
+
+.. data:: YESEXPR
+
+ Return a regular expression that can be used with the regex function to
+ recognize a positive response to a yes/no question.
+
+ .. warning::
+
+ The expression is in the syntax suitable for the :cfunc:`regex` function from
+ the C library, which might differ from the syntax used in :mod:`re`.
+
+
+.. data:: NOEXPR
+
+ Return a regular expression that can be used with the regex(3) function to
+ recognize a negative response to a yes/no question.
+
+
+.. data:: CRNCYSTR
+
+ Return the currency symbol, preceded by "-" if the symbol should appear before
+ the value, "+" if the symbol should appear after the value, or "." if the symbol
+ should replace the radix character.
+
+
+.. data:: ERA
+
+ The return value represents the era used in the current locale.
+
+ Most locales do not define this value. An example of a locale which does define
+ this value is the Japanese one. In Japan, the traditional representation of
+ dates includes the name of the era corresponding to the then-emperor's reign.
+
+ Normally it should not be necessary to use this value directly. Specifying the
+ ``E`` modifier in their format strings causes the :func:`strftime` function to
+ use this information. The format of the returned string is not specified, and
+ therefore you should not assume knowledge of it on different systems.
+
+
+.. data:: ERA_YEAR
+
+ The return value gives the year in the relevant era of the locale.
+
+
+.. data:: ERA_D_T_FMT
+
+ This return value can be used as a format string for :func:`strftime` to
+ represent dates and times in a locale-specific era-based way.
+
+
+.. data:: ERA_D_FMT
+
+ This return value can be used as a format string for :func:`strftime` to
+ represent time in a locale-specific era-based way.
+
+
+.. data:: ALT_DIGITS
+
+ The return value is a representation of up to 100 values used to represent the
+ values 0 to 99.
+
+Example::
+
+ >>> import locale
+ >>> loc = locale.getlocale(locale.LC_ALL) # get current locale
+ >>> locale.setlocale(locale.LC_ALL, 'de_DE') # use German locale; name might vary with platform
+ >>> locale.strcoll('f\xe4n', 'foo') # compare a string containing an umlaut
+ >>> locale.setlocale(locale.LC_ALL, '') # use user's preferred locale
+ >>> locale.setlocale(locale.LC_ALL, 'C') # use default (C) locale
+ >>> locale.setlocale(locale.LC_ALL, loc) # restore saved locale
+
+
+Background, details, hints, tips and caveats
+--------------------------------------------
+
+The C standard defines the locale as a program-wide property that may be
+relatively expensive to change. On top of that, some implementation are broken
+in such a way that frequent locale changes may cause core dumps. This makes the
+locale somewhat painful to use correctly.
+
+Initially, when a program is started, the locale is the ``C`` locale, no matter
+what the user's preferred locale is. The program must explicitly say that it
+wants the user's preferred locale settings by calling ``setlocale(LC_ALL, '')``.
+
+It is generally a bad idea to call :func:`setlocale` in some library routine,
+since as a side effect it affects the entire program. Saving and restoring it
+is almost as bad: it is expensive and affects other threads that happen to run
+before the settings have been restored.
+
+If, when coding a module for general use, you need a locale independent version
+of an operation that is affected by the locale (such as :func:`string.lower`, or
+certain formats used with :func:`time.strftime`), you will have to find a way to
+do it without using the standard library routine. Even better is convincing
+yourself that using locale settings is okay. Only as a last resort should you
+document that your module is not compatible with non-\ ``C`` locale settings.
+
+.. index:: module: string
+
+The case conversion functions in the :mod:`string` module are affected by the
+locale settings. When a call to the :func:`setlocale` function changes the
+:const:`LC_CTYPE` settings, the variables ``string.lowercase``,
+``string.uppercase`` and ``string.letters`` are recalculated. Note that code
+that uses these variable through ':keyword:`from` ... :keyword:`import` ...',
+e.g. ``from string import letters``, is not affected by subsequent
+:func:`setlocale` calls.
+
+The only way to perform numeric operations according to the locale is to use the
+special functions defined by this module: :func:`atof`, :func:`atoi`,
+:func:`format`, :func:`str`.
+
+
+.. _embedding-locale:
+
+For extension writers and programs that embed Python
+----------------------------------------------------
+
+Extension modules should never call :func:`setlocale`, except to find out what
+the current locale is. But since the return value can only be used portably to
+restore it, that is not very useful (except perhaps to find out whether or not
+the locale is ``C``).
+
+When Python code uses the :mod:`locale` module to change the locale, this also
+affects the embedding application. If the embedding application doesn't want
+this to happen, it should remove the :mod:`_locale` extension module (which does
+all the work) from the table of built-in modules in the :file:`config.c` file,
+and make sure that the :mod:`_locale` module is not accessible as a shared
+library.
+
+
+.. _locale-gettext:
+
+Access to message catalogs
+--------------------------
+
+The locale module exposes the C library's gettext interface on systems that
+provide this interface. It consists of the functions :func:`gettext`,
+:func:`dgettext`, :func:`dcgettext`, :func:`textdomain`, :func:`bindtextdomain`,
+and :func:`bind_textdomain_codeset`. These are similar to the same functions in
+the :mod:`gettext` module, but use the C library's binary format for message
+catalogs, and the C library's search algorithms for locating message catalogs.
+
+Python applications should normally find no need to invoke these functions, and
+should use :mod:`gettext` instead. A known exception to this rule are
+applications that link use additional C libraries which internally invoke
+:cfunc:`gettext` or :func:`dcgettext`. For these applications, it may be
+necessary to bind the text domain, so that the libraries can properly locate
+their message catalogs.
+
diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst
new file mode 100644
index 0000000000..218fb0d8e7
--- /dev/null
+++ b/Doc/library/logging.rst
@@ -0,0 +1,1857 @@
+:mod:`logging` --- Logging facility for Python
+==============================================
+
+.. module:: logging
+ :synopsis: Flexible error logging system for applications.
+
+
+.. moduleauthor:: Vinay Sajip <vinay_sajip@red-dove.com>
+.. sectionauthor:: Vinay Sajip <vinay_sajip@red-dove.com>
+
+
+.. % These apply to all modules, and may be given more than once:
+
+
+
+.. index:: pair: Errors; logging
+
+.. versionadded:: 2.3
+
+This module defines functions and classes which implement a flexible error
+logging system for applications.
+
+Logging is performed by calling methods on instances of the :class:`Logger`
+class (hereafter called :dfn:`loggers`). Each instance has a name, and they are
+conceptually arranged in a name space hierarchy using dots (periods) as
+separators. For example, a logger named "scan" is the parent of loggers
+"scan.text", "scan.html" and "scan.pdf". Logger names can be anything you want,
+and indicate the area of an application in which a logged message originates.
+
+Logged messages also have levels of importance associated with them. The default
+levels provided are :const:`DEBUG`, :const:`INFO`, :const:`WARNING`,
+:const:`ERROR` and :const:`CRITICAL`. As a convenience, you indicate the
+importance of a logged message by calling an appropriate method of
+:class:`Logger`. The methods are :meth:`debug`, :meth:`info`, :meth:`warning`,
+:meth:`error` and :meth:`critical`, which mirror the default levels. You are not
+constrained to use these levels: you can specify your own and use a more general
+:class:`Logger` method, :meth:`log`, which takes an explicit level argument.
+
+The numeric values of logging levels are given in the following table. These are
+primarily of interest if you want to define your own levels, and need them to
+have specific values relative to the predefined levels. If you define a level
+with the same numeric value, it overwrites the predefined value; the predefined
+name is lost.
+
++--------------+---------------+
+| Level | Numeric value |
++==============+===============+
+| ``CRITICAL`` | 50 |
++--------------+---------------+
+| ``ERROR`` | 40 |
++--------------+---------------+
+| ``WARNING`` | 30 |
++--------------+---------------+
+| ``INFO`` | 20 |
++--------------+---------------+
+| ``DEBUG`` | 10 |
++--------------+---------------+
+| ``NOTSET`` | 0 |
++--------------+---------------+
+
+Levels can also be associated with loggers, being set either by the developer or
+through loading a saved logging configuration. When a logging method is called
+on a logger, the logger compares its own level with the level associated with
+the method call. If the logger's level is higher than the method call's, no
+logging message is actually generated. This is the basic mechanism controlling
+the verbosity of logging output.
+
+Logging messages are encoded as instances of the :class:`LogRecord` class. When
+a logger decides to actually log an event, a :class:`LogRecord` instance is
+created from the logging message.
+
+Logging messages are subjected to a dispatch mechanism through the use of
+:dfn:`handlers`, which are instances of subclasses of the :class:`Handler`
+class. Handlers are responsible for ensuring that a logged message (in the form
+of a :class:`LogRecord`) ends up in a particular location (or set of locations)
+which is useful for the target audience for that message (such as end users,
+support desk staff, system administrators, developers). Handlers are passed
+:class:`LogRecord` instances intended for particular destinations. Each logger
+can have zero, one or more handlers associated with it (via the
+:meth:`addHandler` method of :class:`Logger`). In addition to any handlers
+directly associated with a logger, *all handlers associated with all ancestors
+of the logger* are called to dispatch the message.
+
+Just as for loggers, handlers can have levels associated with them. A handler's
+level acts as a filter in the same way as a logger's level does. If a handler
+decides to actually dispatch an event, the :meth:`emit` method is used to send
+the message to its destination. Most user-defined subclasses of :class:`Handler`
+will need to override this :meth:`emit`.
+
+In addition to the base :class:`Handler` class, many useful subclasses are
+provided:
+
+#. :class:`StreamHandler` instances send error messages to streams (file-like
+ objects).
+
+#. :class:`FileHandler` instances send error messages to disk files.
+
+#. :class:`BaseRotatingHandler` is the base class for handlers that rotate log
+ files at a certain point. It is not meant to be instantiated directly. Instead,
+ use :class:`RotatingFileHandler` or :class:`TimedRotatingFileHandler`.
+
+#. :class:`RotatingFileHandler` instances send error messages to disk files,
+ with support for maximum log file sizes and log file rotation.
+
+#. :class:`TimedRotatingFileHandler` instances send error messages to disk files
+ rotating the log file at certain timed intervals.
+
+#. :class:`SocketHandler` instances send error messages to TCP/IP sockets.
+
+#. :class:`DatagramHandler` instances send error messages to UDP sockets.
+
+#. :class:`SMTPHandler` instances send error messages to a designated email
+ address.
+
+#. :class:`SysLogHandler` instances send error messages to a Unix syslog daemon,
+ possibly on a remote machine.
+
+#. :class:`NTEventLogHandler` instances send error messages to a Windows
+ NT/2000/XP event log.
+
+#. :class:`MemoryHandler` instances send error messages to a buffer in memory,
+ which is flushed whenever specific criteria are met.
+
+#. :class:`HTTPHandler` instances send error messages to an HTTP server using
+ either ``GET`` or ``POST`` semantics.
+
+The :class:`StreamHandler` and :class:`FileHandler` classes are defined in the
+core logging package. The other handlers are defined in a sub- module,
+:mod:`logging.handlers`. (There is also another sub-module,
+:mod:`logging.config`, for configuration functionality.)
+
+Logged messages are formatted for presentation through instances of the
+:class:`Formatter` class. They are initialized with a format string suitable for
+use with the % operator and a dictionary.
+
+For formatting multiple messages in a batch, instances of
+:class:`BufferingFormatter` can be used. In addition to the format string (which
+is applied to each message in the batch), there is provision for header and
+trailer format strings.
+
+When filtering based on logger level and/or handler level is not enough,
+instances of :class:`Filter` can be added to both :class:`Logger` and
+:class:`Handler` instances (through their :meth:`addFilter` method). Before
+deciding to process a message further, both loggers and handlers consult all
+their filters for permission. If any filter returns a false value, the message
+is not processed further.
+
+The basic :class:`Filter` functionality allows filtering by specific logger
+name. If this feature is used, messages sent to the named logger and its
+children are allowed through the filter, and all others dropped.
+
+In addition to the classes described above, there are a number of module- level
+functions.
+
+
+.. function:: getLogger([name])
+
+ Return a logger with the specified name or, if no name is specified, return a
+ logger which is the root logger of the hierarchy. If specified, the name is
+ typically a dot-separated hierarchical name like *"a"*, *"a.b"* or *"a.b.c.d"*.
+ Choice of these names is entirely up to the developer who is using logging.
+
+ All calls to this function with a given name return the same logger instance.
+ This means that logger instances never need to be passed between different parts
+ of an application.
+
+
+.. function:: getLoggerClass()
+
+ Return either the standard :class:`Logger` class, or the last class passed to
+ :func:`setLoggerClass`. This function may be called from within a new class
+ definition, to ensure that installing a customised :class:`Logger` class will
+ not undo customisations already applied by other code. For example::
+
+ class MyLogger(logging.getLoggerClass()):
+ # ... override behaviour here
+
+
+.. function:: debug(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`DEBUG` on the root logger. The *msg* is the
+ message format string, and the *args* are the arguments which are merged into
+ *msg* using the string formatting operator. (Note that this means that you can
+ use keywords in the format string, together with a single dictionary argument.)
+
+ There are two keyword arguments in *kwargs* which are inspected: *exc_info*
+ which, if it does not evaluate as false, causes exception information to be
+ added to the logging message. If an exception tuple (in the format returned by
+ :func:`sys.exc_info`) is provided, it is used; otherwise, :func:`sys.exc_info`
+ is called to get the exception information.
+
+ The other optional keyword argument is *extra* which can be used to pass a
+ dictionary which is used to populate the __dict__ of the LogRecord created for
+ the logging event with user-defined attributes. These custom attributes can then
+ be used as you like. For example, they could be incorporated into logged
+ messages. For example::
+
+ FORMAT = "%(asctime)-15s %(clientip)s %(user)-8s %(message)s"
+ logging.basicConfig(format=FORMAT)
+ d = {'clientip': '192.168.0.1', 'user': 'fbloggs'}
+ logging.warning("Protocol problem: %s", "connection reset", extra=d)
+
+ would print something like ::
+
+ 2006-02-08 22:20:02,165 192.168.0.1 fbloggs Protocol problem: connection reset
+
+ The keys in the dictionary passed in *extra* should not clash with the keys used
+ by the logging system. (See the :class:`Formatter` documentation for more
+ information on which keys are used by the logging system.)
+
+ If you choose to use these attributes in logged messages, you need to exercise
+ some care. In the above example, for instance, the :class:`Formatter` has been
+ set up with a format string which expects 'clientip' and 'user' in the attribute
+ dictionary of the LogRecord. If these are missing, the message will not be
+ logged because a string formatting exception will occur. So in this case, you
+ always need to pass the *extra* dictionary with these keys.
+
+ While this might be annoying, this feature is intended for use in specialized
+ circumstances, such as multi-threaded servers where the same code executes in
+ many contexts, and interesting conditions which arise are dependent on this
+ context (such as remote client IP address and authenticated user name, in the
+ above example). In such circumstances, it is likely that specialized
+ :class:`Formatter`\ s would be used with particular :class:`Handler`\ s.
+
+ .. versionchanged:: 2.5
+ *extra* was added.
+
+
+.. function:: info(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`INFO` on the root logger. The arguments are
+ interpreted as for :func:`debug`.
+
+
+.. function:: warning(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`WARNING` on the root logger. The arguments are
+ interpreted as for :func:`debug`.
+
+
+.. function:: error(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`ERROR` on the root logger. The arguments are
+ interpreted as for :func:`debug`.
+
+
+.. function:: critical(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`CRITICAL` on the root logger. The arguments
+ are interpreted as for :func:`debug`.
+
+
+.. function:: exception(msg[, *args])
+
+ Logs a message with level :const:`ERROR` on the root logger. The arguments are
+ interpreted as for :func:`debug`. Exception info is added to the logging
+ message. This function should only be called from an exception handler.
+
+
+.. function:: log(level, msg[, *args[, **kwargs]])
+
+ Logs a message with level *level* on the root logger. The other arguments are
+ interpreted as for :func:`debug`.
+
+
+.. function:: disable(lvl)
+
+ Provides an overriding level *lvl* for all loggers which takes precedence over
+ the logger's own level. When the need arises to temporarily throttle logging
+ output down across the whole application, this function can be useful.
+
+
+.. function:: addLevelName(lvl, levelName)
+
+ Associates level *lvl* with text *levelName* in an internal dictionary, which is
+ used to map numeric levels to a textual representation, for example when a
+ :class:`Formatter` formats a message. This function can also be used to define
+ your own levels. The only constraints are that all levels used must be
+ registered using this function, levels should be positive integers and they
+ should increase in increasing order of severity.
+
+
+.. function:: getLevelName(lvl)
+
+ Returns the textual representation of logging level *lvl*. If the level is one
+ of the predefined levels :const:`CRITICAL`, :const:`ERROR`, :const:`WARNING`,
+ :const:`INFO` or :const:`DEBUG` then you get the corresponding string. If you
+ have associated levels with names using :func:`addLevelName` then the name you
+ have associated with *lvl* is returned. If a numeric value corresponding to one
+ of the defined levels is passed in, the corresponding string representation is
+ returned. Otherwise, the string "Level %s" % lvl is returned.
+
+
+.. function:: makeLogRecord(attrdict)
+
+ Creates and returns a new :class:`LogRecord` instance whose attributes are
+ defined by *attrdict*. This function is useful for taking a pickled
+ :class:`LogRecord` attribute dictionary, sent over a socket, and reconstituting
+ it as a :class:`LogRecord` instance at the receiving end.
+
+
+.. function:: basicConfig([**kwargs])
+
+ Does basic configuration for the logging system by creating a
+ :class:`StreamHandler` with a default :class:`Formatter` and adding it to the
+ root logger. The functions :func:`debug`, :func:`info`, :func:`warning`,
+ :func:`error` and :func:`critical` will call :func:`basicConfig` automatically
+ if no handlers are defined for the root logger.
+
+ .. versionchanged:: 2.4
+ Formerly, :func:`basicConfig` did not take any keyword arguments.
+
+ The following keyword arguments are supported.
+
+ +--------------+---------------------------------------------+
+ | Format | Description |
+ +==============+=============================================+
+ | ``filename`` | Specifies that a FileHandler be created, |
+ | | using the specified filename, rather than a |
+ | | StreamHandler. |
+ +--------------+---------------------------------------------+
+ | ``filemode`` | Specifies the mode to open the file, if |
+ | | filename is specified (if filemode is |
+ | | unspecified, it defaults to 'a'). |
+ +--------------+---------------------------------------------+
+ | ``format`` | Use the specified format string for the |
+ | | handler. |
+ +--------------+---------------------------------------------+
+ | ``datefmt`` | Use the specified date/time format. |
+ +--------------+---------------------------------------------+
+ | ``level`` | Set the root logger level to the specified |
+ | | level. |
+ +--------------+---------------------------------------------+
+ | ``stream`` | Use the specified stream to initialize the |
+ | | StreamHandler. Note that this argument is |
+ | | incompatible with 'filename' - if both are |
+ | | present, 'stream' is ignored. |
+ +--------------+---------------------------------------------+
+
+
+.. function:: shutdown()
+
+ Informs the logging system to perform an orderly shutdown by flushing and
+ closing all handlers.
+
+
+.. function:: setLoggerClass(klass)
+
+ Tells the logging system to use the class *klass* when instantiating a logger.
+ The class should define :meth:`__init__` such that only a name argument is
+ required, and the :meth:`__init__` should call :meth:`Logger.__init__`. This
+ function is typically called before any loggers are instantiated by applications
+ which need to use custom logger behavior.
+
+
+.. seealso::
+
+ :pep:`282` - A Logging System
+ The proposal which described this feature for inclusion in the Python standard
+ library.
+
+ `Original Python :mod:`logging` package <http://www.red-dove.com/python_logging.html>`_
+ This is the original source for the :mod:`logging` package. The version of the
+ package available from this site is suitable for use with Python 1.5.2, 2.1.x
+ and 2.2.x, which do not include the :mod:`logging` package in the standard
+ library.
+
+
+Logger Objects
+--------------
+
+Loggers have the following attributes and methods. Note that Loggers are never
+instantiated directly, but always through the module-level function
+``logging.getLogger(name)``.
+
+
+.. attribute:: Logger.propagate
+
+ If this evaluates to false, logging messages are not passed by this logger or by
+ child loggers to higher level (ancestor) loggers. The constructor sets this
+ attribute to 1.
+
+
+.. method:: Logger.setLevel(lvl)
+
+ Sets the threshold for this logger to *lvl*. Logging messages which are less
+ severe than *lvl* will be ignored. When a logger is created, the level is set to
+ :const:`NOTSET` (which causes all messages to be processed when the logger is
+ the root logger, or delegation to the parent when the logger is a non-root
+ logger). Note that the root logger is created with level :const:`WARNING`.
+
+ The term "delegation to the parent" means that if a logger has a level of
+ NOTSET, its chain of ancestor loggers is traversed until either an ancestor with
+ a level other than NOTSET is found, or the root is reached.
+
+ If an ancestor is found with a level other than NOTSET, then that ancestor's
+ level is treated as the effective level of the logger where the ancestor search
+ began, and is used to determine how a logging event is handled.
+
+ If the root is reached, and it has a level of NOTSET, then all messages will be
+ processed. Otherwise, the root's level will be used as the effective level.
+
+
+.. method:: Logger.isEnabledFor(lvl)
+
+ Indicates if a message of severity *lvl* would be processed by this logger.
+ This method checks first the module-level level set by
+ ``logging.disable(lvl)`` and then the logger's effective level as determined
+ by :meth:`getEffectiveLevel`.
+
+
+.. method:: Logger.getEffectiveLevel()
+
+ Indicates the effective level for this logger. If a value other than
+ :const:`NOTSET` has been set using :meth:`setLevel`, it is returned. Otherwise,
+ the hierarchy is traversed towards the root until a value other than
+ :const:`NOTSET` is found, and that value is returned.
+
+
+.. method:: Logger.debug(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`DEBUG` on this logger. The *msg* is the
+ message format string, and the *args* are the arguments which are merged into
+ *msg* using the string formatting operator. (Note that this means that you can
+ use keywords in the format string, together with a single dictionary argument.)
+
+ There are two keyword arguments in *kwargs* which are inspected: *exc_info*
+ which, if it does not evaluate as false, causes exception information to be
+ added to the logging message. If an exception tuple (in the format returned by
+ :func:`sys.exc_info`) is provided, it is used; otherwise, :func:`sys.exc_info`
+ is called to get the exception information.
+
+ The other optional keyword argument is *extra* which can be used to pass a
+ dictionary which is used to populate the __dict__ of the LogRecord created for
+ the logging event with user-defined attributes. These custom attributes can then
+ be used as you like. For example, they could be incorporated into logged
+ messages. For example::
+
+ FORMAT = "%(asctime)-15s %(clientip)s %(user)-8s %(message)s"
+ logging.basicConfig(format=FORMAT)
+ dict = { 'clientip' : '192.168.0.1', 'user' : 'fbloggs' }
+ logger = logging.getLogger("tcpserver")
+ logger.warning("Protocol problem: %s", "connection reset", extra=d)
+
+ would print something like ::
+
+ 2006-02-08 22:20:02,165 192.168.0.1 fbloggs Protocol problem: connection reset
+
+ The keys in the dictionary passed in *extra* should not clash with the keys used
+ by the logging system. (See the :class:`Formatter` documentation for more
+ information on which keys are used by the logging system.)
+
+ If you choose to use these attributes in logged messages, you need to exercise
+ some care. In the above example, for instance, the :class:`Formatter` has been
+ set up with a format string which expects 'clientip' and 'user' in the attribute
+ dictionary of the LogRecord. If these are missing, the message will not be
+ logged because a string formatting exception will occur. So in this case, you
+ always need to pass the *extra* dictionary with these keys.
+
+ While this might be annoying, this feature is intended for use in specialized
+ circumstances, such as multi-threaded servers where the same code executes in
+ many contexts, and interesting conditions which arise are dependent on this
+ context (such as remote client IP address and authenticated user name, in the
+ above example). In such circumstances, it is likely that specialized
+ :class:`Formatter`\ s would be used with particular :class:`Handler`\ s.
+
+ .. versionchanged:: 2.5
+ *extra* was added.
+
+
+.. method:: Logger.info(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`INFO` on this logger. The arguments are
+ interpreted as for :meth:`debug`.
+
+
+.. method:: Logger.warning(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`WARNING` on this logger. The arguments are
+ interpreted as for :meth:`debug`.
+
+
+.. method:: Logger.error(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`ERROR` on this logger. The arguments are
+ interpreted as for :meth:`debug`.
+
+
+.. method:: Logger.critical(msg[, *args[, **kwargs]])
+
+ Logs a message with level :const:`CRITICAL` on this logger. The arguments are
+ interpreted as for :meth:`debug`.
+
+
+.. method:: Logger.log(lvl, msg[, *args[, **kwargs]])
+
+ Logs a message with integer level *lvl* on this logger. The other arguments are
+ interpreted as for :meth:`debug`.
+
+
+.. method:: Logger.exception(msg[, *args])
+
+ Logs a message with level :const:`ERROR` on this logger. The arguments are
+ interpreted as for :meth:`debug`. Exception info is added to the logging
+ message. This method should only be called from an exception handler.
+
+
+.. method:: Logger.addFilter(filt)
+
+ Adds the specified filter *filt* to this logger.
+
+
+.. method:: Logger.removeFilter(filt)
+
+ Removes the specified filter *filt* from this logger.
+
+
+.. method:: Logger.filter(record)
+
+ Applies this logger's filters to the record and returns a true value if the
+ record is to be processed.
+
+
+.. method:: Logger.addHandler(hdlr)
+
+ Adds the specified handler *hdlr* to this logger.
+
+
+.. method:: Logger.removeHandler(hdlr)
+
+ Removes the specified handler *hdlr* from this logger.
+
+
+.. method:: Logger.findCaller()
+
+ Finds the caller's source filename and line number. Returns the filename, line
+ number and function name as a 3-element tuple.
+
+ .. versionchanged:: 2.5
+ The function name was added. In earlier versions, the filename and line number
+ were returned as a 2-element tuple..
+
+
+.. method:: Logger.handle(record)
+
+ Handles a record by passing it to all handlers associated with this logger and
+ its ancestors (until a false value of *propagate* is found). This method is used
+ for unpickled records received from a socket, as well as those created locally.
+ Logger-level filtering is applied using :meth:`filter`.
+
+
+.. method:: Logger.makeRecord(name, lvl, fn, lno, msg, args, exc_info [, func, extra])
+
+ This is a factory method which can be overridden in subclasses to create
+ specialized :class:`LogRecord` instances.
+
+ .. versionchanged:: 2.5
+ *func* and *extra* were added.
+
+
+.. _minimal-example:
+
+Basic example
+-------------
+
+.. versionchanged:: 2.4
+ formerly :func:`basicConfig` did not take any keyword arguments.
+
+The :mod:`logging` package provides a lot of flexibility, and its configuration
+can appear daunting. This section demonstrates that simple use of the logging
+package is possible.
+
+The simplest example shows logging to the console::
+
+ import logging
+
+ logging.debug('A debug message')
+ logging.info('Some information')
+ logging.warning('A shot across the bows')
+
+If you run the above script, you'll see this::
+
+ WARNING:root:A shot across the bows
+
+Because no particular logger was specified, the system used the root logger. The
+debug and info messages didn't appear because by default, the root logger is
+configured to only handle messages with a severity of WARNING or above. The
+message format is also a configuration default, as is the output destination of
+the messages - ``sys.stderr``. The severity level, the message format and
+destination can be easily changed, as shown in the example below::
+
+ import logging
+
+ logging.basicConfig(level=logging.DEBUG,
+ format='%(asctime)s %(levelname)s %(message)s',
+ filename='/tmp/myapp.log',
+ filemode='w')
+ logging.debug('A debug message')
+ logging.info('Some information')
+ logging.warning('A shot across the bows')
+
+The :meth:`basicConfig` method is used to change the configuration defaults,
+which results in output (written to ``/tmp/myapp.log``) which should look
+something like the following::
+
+ 2004-07-02 13:00:08,743 DEBUG A debug message
+ 2004-07-02 13:00:08,743 INFO Some information
+ 2004-07-02 13:00:08,743 WARNING A shot across the bows
+
+This time, all messages with a severity of DEBUG or above were handled, and the
+format of the messages was also changed, and output went to the specified file
+rather than the console.
+
+Formatting uses standard Python string formatting - see section
+:ref:`string-formatting`. The format string takes the following common
+specifiers. For a complete list of specifiers, consult the :class:`Formatter`
+documentation.
+
++-------------------+-----------------------------------------------+
+| Format | Description |
++===================+===============================================+
+| ``%(name)s`` | Name of the logger (logging channel). |
++-------------------+-----------------------------------------------+
+| ``%(levelname)s`` | Text logging level for the message |
+| | (``'DEBUG'``, ``'INFO'``, ``'WARNING'``, |
+| | ``'ERROR'``, ``'CRITICAL'``). |
++-------------------+-----------------------------------------------+
+| ``%(asctime)s`` | Human-readable time when the |
+| | :class:`LogRecord` was created. By default |
+| | this is of the form "2003-07-08 16:49:45,896" |
+| | (the numbers after the comma are millisecond |
+| | portion of the time). |
++-------------------+-----------------------------------------------+
+| ``%(message)s`` | The logged message. |
++-------------------+-----------------------------------------------+
+
+To change the date/time format, you can pass an additional keyword parameter,
+*datefmt*, as in the following::
+
+ import logging
+
+ logging.basicConfig(level=logging.DEBUG,
+ format='%(asctime)s %(levelname)-8s %(message)s',
+ datefmt='%a, %d %b %Y %H:%M:%S',
+ filename='/temp/myapp.log',
+ filemode='w')
+ logging.debug('A debug message')
+ logging.info('Some information')
+ logging.warning('A shot across the bows')
+
+which would result in output like ::
+
+ Fri, 02 Jul 2004 13:06:18 DEBUG A debug message
+ Fri, 02 Jul 2004 13:06:18 INFO Some information
+ Fri, 02 Jul 2004 13:06:18 WARNING A shot across the bows
+
+The date format string follows the requirements of :func:`strftime` - see the
+documentation for the :mod:`time` module.
+
+If, instead of sending logging output to the console or a file, you'd rather use
+a file-like object which you have created separately, you can pass it to
+:func:`basicConfig` using the *stream* keyword argument. Note that if both
+*stream* and *filename* keyword arguments are passed, the *stream* argument is
+ignored.
+
+Of course, you can put variable information in your output. To do this, simply
+have the message be a format string and pass in additional arguments containing
+the variable information, as in the following example::
+
+ import logging
+
+ logging.basicConfig(level=logging.DEBUG,
+ format='%(asctime)s %(levelname)-8s %(message)s',
+ datefmt='%a, %d %b %Y %H:%M:%S',
+ filename='/temp/myapp.log',
+ filemode='w')
+ logging.error('Pack my box with %d dozen %s', 5, 'liquor jugs')
+
+which would result in ::
+
+ Wed, 21 Jul 2004 15:35:16 ERROR Pack my box with 5 dozen liquor jugs
+
+
+.. _multiple-destinations:
+
+Logging to multiple destinations
+--------------------------------
+
+Let's say you want to log to console and file with different message formats and
+in differing circumstances. Say you want to log messages with levels of DEBUG
+and higher to file, and those messages at level INFO and higher to the console.
+Let's also assume that the file should contain timestamps, but the console
+messages should not. Here's how you can achieve this::
+
+ import logging
+
+ # set up logging to file - see previous section for more details
+ logging.basicConfig(level=logging.DEBUG,
+ format='%(asctime)s %(name)-12s %(levelname)-8s %(message)s',
+ datefmt='%m-%d %H:%M',
+ filename='/temp/myapp.log',
+ filemode='w')
+ # define a Handler which writes INFO messages or higher to the sys.stderr
+ console = logging.StreamHandler()
+ console.setLevel(logging.INFO)
+ # set a format which is simpler for console use
+ formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s')
+ # tell the handler to use this format
+ console.setFormatter(formatter)
+ # add the handler to the root logger
+ logging.getLogger('').addHandler(console)
+
+ # Now, we can log to the root logger, or any other logger. First the root...
+ logging.info('Jackdaws love my big sphinx of quartz.')
+
+ # Now, define a couple of other loggers which might represent areas in your
+ # application:
+
+ logger1 = logging.getLogger('myapp.area1')
+ logger2 = logging.getLogger('myapp.area2')
+
+ logger1.debug('Quick zephyrs blow, vexing daft Jim.')
+ logger1.info('How quickly daft jumping zebras vex.')
+ logger2.warning('Jail zesty vixen who grabbed pay from quack.')
+ logger2.error('The five boxing wizards jump quickly.')
+
+When you run this, on the console you will see ::
+
+ root : INFO Jackdaws love my big sphinx of quartz.
+ myapp.area1 : INFO How quickly daft jumping zebras vex.
+ myapp.area2 : WARNING Jail zesty vixen who grabbed pay from quack.
+ myapp.area2 : ERROR The five boxing wizards jump quickly.
+
+and in the file you will see something like ::
+
+ 10-22 22:19 root INFO Jackdaws love my big sphinx of quartz.
+ 10-22 22:19 myapp.area1 DEBUG Quick zephyrs blow, vexing daft Jim.
+ 10-22 22:19 myapp.area1 INFO How quickly daft jumping zebras vex.
+ 10-22 22:19 myapp.area2 WARNING Jail zesty vixen who grabbed pay from quack.
+ 10-22 22:19 myapp.area2 ERROR The five boxing wizards jump quickly.
+
+As you can see, the DEBUG message only shows up in the file. The other messages
+are sent to both destinations.
+
+This example uses console and file handlers, but you can use any number and
+combination of handlers you choose.
+
+
+.. _network-logging:
+
+Sending and receiving logging events across a network
+-----------------------------------------------------
+
+Let's say you want to send logging events across a network, and handle them at
+the receiving end. A simple way of doing this is attaching a
+:class:`SocketHandler` instance to the root logger at the sending end::
+
+ import logging, logging.handlers
+
+ rootLogger = logging.getLogger('')
+ rootLogger.setLevel(logging.DEBUG)
+ socketHandler = logging.handlers.SocketHandler('localhost',
+ logging.handlers.DEFAULT_TCP_LOGGING_PORT)
+ # don't bother with a formatter, since a socket handler sends the event as
+ # an unformatted pickle
+ rootLogger.addHandler(socketHandler)
+
+ # Now, we can log to the root logger, or any other logger. First the root...
+ logging.info('Jackdaws love my big sphinx of quartz.')
+
+ # Now, define a couple of other loggers which might represent areas in your
+ # application:
+
+ logger1 = logging.getLogger('myapp.area1')
+ logger2 = logging.getLogger('myapp.area2')
+
+ logger1.debug('Quick zephyrs blow, vexing daft Jim.')
+ logger1.info('How quickly daft jumping zebras vex.')
+ logger2.warning('Jail zesty vixen who grabbed pay from quack.')
+ logger2.error('The five boxing wizards jump quickly.')
+
+At the receiving end, you can set up a receiver using the :mod:`SocketServer`
+module. Here is a basic working example::
+
+ import cPickle
+ import logging
+ import logging.handlers
+ import SocketServer
+ import struct
+
+
+ class LogRecordStreamHandler(SocketServer.StreamRequestHandler):
+ """Handler for a streaming logging request.
+
+ This basically logs the record using whatever logging policy is
+ configured locally.
+ """
+
+ def handle(self):
+ """
+ Handle multiple requests - each expected to be a 4-byte length,
+ followed by the LogRecord in pickle format. Logs the record
+ according to whatever policy is configured locally.
+ """
+ while 1:
+ chunk = self.connection.recv(4)
+ if len(chunk) < 4:
+ break
+ slen = struct.unpack(">L", chunk)[0]
+ chunk = self.connection.recv(slen)
+ while len(chunk) < slen:
+ chunk = chunk + self.connection.recv(slen - len(chunk))
+ obj = self.unPickle(chunk)
+ record = logging.makeLogRecord(obj)
+ self.handleLogRecord(record)
+
+ def unPickle(self, data):
+ return cPickle.loads(data)
+
+ def handleLogRecord(self, record):
+ # if a name is specified, we use the named logger rather than the one
+ # implied by the record.
+ if self.server.logname is not None:
+ name = self.server.logname
+ else:
+ name = record.name
+ logger = logging.getLogger(name)
+ # N.B. EVERY record gets logged. This is because Logger.handle
+ # is normally called AFTER logger-level filtering. If you want
+ # to do filtering, do it at the client end to save wasting
+ # cycles and network bandwidth!
+ logger.handle(record)
+
+ class LogRecordSocketReceiver(SocketServer.ThreadingTCPServer):
+ """simple TCP socket-based logging receiver suitable for testing.
+ """
+
+ allow_reuse_address = 1
+
+ def __init__(self, host='localhost',
+ port=logging.handlers.DEFAULT_TCP_LOGGING_PORT,
+ handler=LogRecordStreamHandler):
+ SocketServer.ThreadingTCPServer.__init__(self, (host, port), handler)
+ self.abort = 0
+ self.timeout = 1
+ self.logname = None
+
+ def serve_until_stopped(self):
+ import select
+ abort = 0
+ while not abort:
+ rd, wr, ex = select.select([self.socket.fileno()],
+ [], [],
+ self.timeout)
+ if rd:
+ self.handle_request()
+ abort = self.abort
+
+ def main():
+ logging.basicConfig(
+ format="%(relativeCreated)5d %(name)-15s %(levelname)-8s %(message)s")
+ tcpserver = LogRecordSocketReceiver()
+ print "About to start TCP server..."
+ tcpserver.serve_until_stopped()
+
+ if __name__ == "__main__":
+ main()
+
+First run the server, and then the client. On the client side, nothing is
+printed on the console; on the server side, you should see something like::
+
+ About to start TCP server...
+ 59 root INFO Jackdaws love my big sphinx of quartz.
+ 59 myapp.area1 DEBUG Quick zephyrs blow, vexing daft Jim.
+ 69 myapp.area1 INFO How quickly daft jumping zebras vex.
+ 69 myapp.area2 WARNING Jail zesty vixen who grabbed pay from quack.
+ 69 myapp.area2 ERROR The five boxing wizards jump quickly.
+
+
+Handler Objects
+---------------
+
+Handlers have the following attributes and methods. Note that :class:`Handler`
+is never instantiated directly; this class acts as a base for more useful
+subclasses. However, the :meth:`__init__` method in subclasses needs to call
+:meth:`Handler.__init__`.
+
+
+.. method:: Handler.__init__(level=NOTSET)
+
+ Initializes the :class:`Handler` instance by setting its level, setting the list
+ of filters to the empty list and creating a lock (using :meth:`createLock`) for
+ serializing access to an I/O mechanism.
+
+
+.. method:: Handler.createLock()
+
+ Initializes a thread lock which can be used to serialize access to underlying
+ I/O functionality which may not be threadsafe.
+
+
+.. method:: Handler.acquire()
+
+ Acquires the thread lock created with :meth:`createLock`.
+
+
+.. method:: Handler.release()
+
+ Releases the thread lock acquired with :meth:`acquire`.
+
+
+.. method:: Handler.setLevel(lvl)
+
+ Sets the threshold for this handler to *lvl*. Logging messages which are less
+ severe than *lvl* will be ignored. When a handler is created, the level is set
+ to :const:`NOTSET` (which causes all messages to be processed).
+
+
+.. method:: Handler.setFormatter(form)
+
+ Sets the :class:`Formatter` for this handler to *form*.
+
+
+.. method:: Handler.addFilter(filt)
+
+ Adds the specified filter *filt* to this handler.
+
+
+.. method:: Handler.removeFilter(filt)
+
+ Removes the specified filter *filt* from this handler.
+
+
+.. method:: Handler.filter(record)
+
+ Applies this handler's filters to the record and returns a true value if the
+ record is to be processed.
+
+
+.. method:: Handler.flush()
+
+ Ensure all logging output has been flushed. This version does nothing and is
+ intended to be implemented by subclasses.
+
+
+.. method:: Handler.close()
+
+ Tidy up any resources used by the handler. This version does nothing and is
+ intended to be implemented by subclasses.
+
+
+.. method:: Handler.handle(record)
+
+ Conditionally emits the specified logging record, depending on filters which may
+ have been added to the handler. Wraps the actual emission of the record with
+ acquisition/release of the I/O thread lock.
+
+
+.. method:: Handler.handleError(record)
+
+ This method should be called from handlers when an exception is encountered
+ during an :meth:`emit` call. By default it does nothing, which means that
+ exceptions get silently ignored. This is what is mostly wanted for a logging
+ system - most users will not care about errors in the logging system, they are
+ more interested in application errors. You could, however, replace this with a
+ custom handler if you wish. The specified record is the one which was being
+ processed when the exception occurred.
+
+
+.. method:: Handler.format(record)
+
+ Do formatting for a record - if a formatter is set, use it. Otherwise, use the
+ default formatter for the module.
+
+
+.. method:: Handler.emit(record)
+
+ Do whatever it takes to actually log the specified logging record. This version
+ is intended to be implemented by subclasses and so raises a
+ :exc:`NotImplementedError`.
+
+
+StreamHandler
+^^^^^^^^^^^^^
+
+The :class:`StreamHandler` class, located in the core :mod:`logging` package,
+sends logging output to streams such as *sys.stdout*, *sys.stderr* or any
+file-like object (or, more precisely, any object which supports :meth:`write`
+and :meth:`flush` methods).
+
+
+.. class:: StreamHandler([strm])
+
+ Returns a new instance of the :class:`StreamHandler` class. If *strm* is
+ specified, the instance will use it for logging output; otherwise, *sys.stderr*
+ will be used.
+
+
+.. method:: StreamHandler.emit(record)
+
+ If a formatter is specified, it is used to format the record. The record is then
+ written to the stream with a trailing newline. If exception information is
+ present, it is formatted using :func:`traceback.print_exception` and appended to
+ the stream.
+
+
+.. method:: StreamHandler.flush()
+
+ Flushes the stream by calling its :meth:`flush` method. Note that the
+ :meth:`close` method is inherited from :class:`Handler` and so does nothing, so
+ an explicit :meth:`flush` call may be needed at times.
+
+
+FileHandler
+^^^^^^^^^^^
+
+The :class:`FileHandler` class, located in the core :mod:`logging` package,
+sends logging output to a disk file. It inherits the output functionality from
+:class:`StreamHandler`.
+
+
+.. class:: FileHandler(filename[, mode[, encoding]])
+
+ Returns a new instance of the :class:`FileHandler` class. The specified file is
+ opened and used as the stream for logging. If *mode* is not specified,
+ :const:`'a'` is used. If *encoding* is not *None*, it is used to open the file
+ with that encoding. By default, the file grows indefinitely.
+
+
+.. method:: FileHandler.close()
+
+ Closes the file.
+
+
+.. method:: FileHandler.emit(record)
+
+ Outputs the record to the file.
+
+
+WatchedFileHandler
+^^^^^^^^^^^^^^^^^^
+
+.. versionadded:: 2.6
+
+The :class:`WatchedFileHandler` class, located in the :mod:`logging.handlers`
+module, is a :class:`FileHandler` which watches the file it is logging to. If
+the file changes, it is closed and reopened using the file name.
+
+A file change can happen because of usage of programs such as *newsyslog* and
+*logrotate* which perform log file rotation. This handler, intended for use
+under Unix/Linux, watches the file to see if it has changed since the last emit.
+(A file is deemed to have changed if its device or inode have changed.) If the
+file has changed, the old file stream is closed, and the file opened to get a
+new stream.
+
+This handler is not appropriate for use under Windows, because under Windows
+open log files cannot be moved or renamed - logging opens the files with
+exclusive locks - and so there is no need for such a handler. Furthermore,
+*ST_INO* is not supported under Windows; :func:`stat` always returns zero for
+this value.
+
+
+.. class:: WatchedFileHandler(filename[,mode[, encoding]])
+
+ Returns a new instance of the :class:`WatchedFileHandler` class. The specified
+ file is opened and used as the stream for logging. If *mode* is not specified,
+ :const:`'a'` is used. If *encoding* is not *None*, it is used to open the file
+ with that encoding. By default, the file grows indefinitely.
+
+
+.. method:: WatchedFileHandler.emit(record)
+
+ Outputs the record to the file, but first checks to see if the file has changed.
+ If it has, the existing stream is flushed and closed and the file opened again,
+ before outputting the record to the file.
+
+
+RotatingFileHandler
+^^^^^^^^^^^^^^^^^^^
+
+The :class:`RotatingFileHandler` class, located in the :mod:`logging.handlers`
+module, supports rotation of disk log files.
+
+
+.. class:: RotatingFileHandler(filename[, mode[, maxBytes[, backupCount]]])
+
+ Returns a new instance of the :class:`RotatingFileHandler` class. The specified
+ file is opened and used as the stream for logging. If *mode* is not specified,
+ ``'a'`` is used. By default, the file grows indefinitely.
+
+ You can use the *maxBytes* and *backupCount* values to allow the file to
+ :dfn:`rollover` at a predetermined size. When the size is about to be exceeded,
+ the file is closed and a new file is silently opened for output. Rollover occurs
+ whenever the current log file is nearly *maxBytes* in length; if *maxBytes* is
+ zero, rollover never occurs. If *backupCount* is non-zero, the system will save
+ old log files by appending the extensions ".1", ".2" etc., to the filename. For
+ example, with a *backupCount* of 5 and a base file name of :file:`app.log`, you
+ would get :file:`app.log`, :file:`app.log.1`, :file:`app.log.2`, up to
+ :file:`app.log.5`. The file being written to is always :file:`app.log`. When
+ this file is filled, it is closed and renamed to :file:`app.log.1`, and if files
+ :file:`app.log.1`, :file:`app.log.2`, etc. exist, then they are renamed to
+ :file:`app.log.2`, :file:`app.log.3` etc. respectively.
+
+
+.. method:: RotatingFileHandler.doRollover()
+
+ Does a rollover, as described above.
+
+
+.. method:: RotatingFileHandler.emit(record)
+
+ Outputs the record to the file, catering for rollover as described previously.
+
+
+TimedRotatingFileHandler
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+The :class:`TimedRotatingFileHandler` class, located in the
+:mod:`logging.handlers` module, supports rotation of disk log files at certain
+timed intervals.
+
+
+.. class:: TimedRotatingFileHandler(filename [,when [,interval [,backupCount]]])
+
+ Returns a new instance of the :class:`TimedRotatingFileHandler` class. The
+ specified file is opened and used as the stream for logging. On rotating it also
+ sets the filename suffix. Rotating happens based on the product of *when* and
+ *interval*.
+
+ You can use the *when* to specify the type of *interval*. The list of possible
+ values is, note that they are not case sensitive:
+
+ +----------+-----------------------+
+ | Value | Type of interval |
+ +==========+=======================+
+ | S | Seconds |
+ +----------+-----------------------+
+ | M | Minutes |
+ +----------+-----------------------+
+ | H | Hours |
+ +----------+-----------------------+
+ | D | Days |
+ +----------+-----------------------+
+ | W | Week day (0=Monday) |
+ +----------+-----------------------+
+ | midnight | Roll over at midnight |
+ +----------+-----------------------+
+
+ If *backupCount* is non-zero, the system will save old log files by appending
+ extensions to the filename. The extensions are date-and-time based, using the
+ strftime format ``%Y-%m-%d_%H-%M-%S`` or a leading portion thereof, depending on
+ the rollover interval. At most *backupCount* files will be kept, and if more
+ would be created when rollover occurs, the oldest one is deleted.
+
+
+.. method:: TimedRotatingFileHandler.doRollover()
+
+ Does a rollover, as described above.
+
+
+.. method:: TimedRotatingFileHandler.emit(record)
+
+ Outputs the record to the file, catering for rollover as described above.
+
+
+SocketHandler
+^^^^^^^^^^^^^
+
+The :class:`SocketHandler` class, located in the :mod:`logging.handlers` module,
+sends logging output to a network socket. The base class uses a TCP socket.
+
+
+.. class:: SocketHandler(host, port)
+
+ Returns a new instance of the :class:`SocketHandler` class intended to
+ communicate with a remote machine whose address is given by *host* and *port*.
+
+
+.. method:: SocketHandler.close()
+
+ Closes the socket.
+
+
+.. method:: SocketHandler.emit()
+
+ Pickles the record's attribute dictionary and writes it to the socket in binary
+ format. If there is an error with the socket, silently drops the packet. If the
+ connection was previously lost, re-establishes the connection. To unpickle the
+ record at the receiving end into a :class:`LogRecord`, use the
+ :func:`makeLogRecord` function.
+
+
+.. method:: SocketHandler.handleError()
+
+ Handles an error which has occurred during :meth:`emit`. The most likely cause
+ is a lost connection. Closes the socket so that we can retry on the next event.
+
+
+.. method:: SocketHandler.makeSocket()
+
+ This is a factory method which allows subclasses to define the precise type of
+ socket they want. The default implementation creates a TCP socket
+ (:const:`socket.SOCK_STREAM`).
+
+
+.. method:: SocketHandler.makePickle(record)
+
+ Pickles the record's attribute dictionary in binary format with a length prefix,
+ and returns it ready for transmission across the socket.
+
+
+.. method:: SocketHandler.send(packet)
+
+ Send a pickled string *packet* to the socket. This function allows for partial
+ sends which can happen when the network is busy.
+
+
+DatagramHandler
+^^^^^^^^^^^^^^^
+
+The :class:`DatagramHandler` class, located in the :mod:`logging.handlers`
+module, inherits from :class:`SocketHandler` to support sending logging messages
+over UDP sockets.
+
+
+.. class:: DatagramHandler(host, port)
+
+ Returns a new instance of the :class:`DatagramHandler` class intended to
+ communicate with a remote machine whose address is given by *host* and *port*.
+
+
+.. method:: DatagramHandler.emit()
+
+ Pickles the record's attribute dictionary and writes it to the socket in binary
+ format. If there is an error with the socket, silently drops the packet. To
+ unpickle the record at the receiving end into a :class:`LogRecord`, use the
+ :func:`makeLogRecord` function.
+
+
+.. method:: DatagramHandler.makeSocket()
+
+ The factory method of :class:`SocketHandler` is here overridden to create a UDP
+ socket (:const:`socket.SOCK_DGRAM`).
+
+
+.. method:: DatagramHandler.send(s)
+
+ Send a pickled string to a socket.
+
+
+SysLogHandler
+^^^^^^^^^^^^^
+
+The :class:`SysLogHandler` class, located in the :mod:`logging.handlers` module,
+supports sending logging messages to a remote or local Unix syslog.
+
+
+.. class:: SysLogHandler([address[, facility]])
+
+ Returns a new instance of the :class:`SysLogHandler` class intended to
+ communicate with a remote Unix machine whose address is given by *address* in
+ the form of a ``(host, port)`` tuple. If *address* is not specified,
+ ``('localhost', 514)`` is used. The address is used to open a UDP socket. An
+ alternative to providing a ``(host, port)`` tuple is providing an address as a
+ string, for example "/dev/log". In this case, a Unix domain socket is used to
+ send the message to the syslog. If *facility* is not specified,
+ :const:`LOG_USER` is used.
+
+
+.. method:: SysLogHandler.close()
+
+ Closes the socket to the remote host.
+
+
+.. method:: SysLogHandler.emit(record)
+
+ The record is formatted, and then sent to the syslog server. If exception
+ information is present, it is *not* sent to the server.
+
+
+.. method:: SysLogHandler.encodePriority(facility, priority)
+
+ Encodes the facility and priority into an integer. You can pass in strings or
+ integers - if strings are passed, internal mapping dictionaries are used to
+ convert them to integers.
+
+
+NTEventLogHandler
+^^^^^^^^^^^^^^^^^
+
+The :class:`NTEventLogHandler` class, located in the :mod:`logging.handlers`
+module, supports sending logging messages to a local Windows NT, Windows 2000 or
+Windows XP event log. Before you can use it, you need Mark Hammond's Win32
+extensions for Python installed.
+
+
+.. class:: NTEventLogHandler(appname[, dllname[, logtype]])
+
+ Returns a new instance of the :class:`NTEventLogHandler` class. The *appname* is
+ used to define the application name as it appears in the event log. An
+ appropriate registry entry is created using this name. The *dllname* should give
+ the fully qualified pathname of a .dll or .exe which contains message
+ definitions to hold in the log (if not specified, ``'win32service.pyd'`` is used
+ - this is installed with the Win32 extensions and contains some basic
+ placeholder message definitions. Note that use of these placeholders will make
+ your event logs big, as the entire message source is held in the log. If you
+ want slimmer logs, you have to pass in the name of your own .dll or .exe which
+ contains the message definitions you want to use in the event log). The
+ *logtype* is one of ``'Application'``, ``'System'`` or ``'Security'``, and
+ defaults to ``'Application'``.
+
+
+.. method:: NTEventLogHandler.close()
+
+ At this point, you can remove the application name from the registry as a source
+ of event log entries. However, if you do this, you will not be able to see the
+ events as you intended in the Event Log Viewer - it needs to be able to access
+ the registry to get the .dll name. The current version does not do this (in fact
+ it doesn't do anything).
+
+
+.. method:: NTEventLogHandler.emit(record)
+
+ Determines the message ID, event category and event type, and then logs the
+ message in the NT event log.
+
+
+.. method:: NTEventLogHandler.getEventCategory(record)
+
+ Returns the event category for the record. Override this if you want to specify
+ your own categories. This version returns 0.
+
+
+.. method:: NTEventLogHandler.getEventType(record)
+
+ Returns the event type for the record. Override this if you want to specify your
+ own types. This version does a mapping using the handler's typemap attribute,
+ which is set up in :meth:`__init__` to a dictionary which contains mappings for
+ :const:`DEBUG`, :const:`INFO`, :const:`WARNING`, :const:`ERROR` and
+ :const:`CRITICAL`. If you are using your own levels, you will either need to
+ override this method or place a suitable dictionary in the handler's *typemap*
+ attribute.
+
+
+.. method:: NTEventLogHandler.getMessageID(record)
+
+ Returns the message ID for the record. If you are using your own messages, you
+ could do this by having the *msg* passed to the logger being an ID rather than a
+ format string. Then, in here, you could use a dictionary lookup to get the
+ message ID. This version returns 1, which is the base message ID in
+ :file:`win32service.pyd`.
+
+
+SMTPHandler
+^^^^^^^^^^^
+
+The :class:`SMTPHandler` class, located in the :mod:`logging.handlers` module,
+supports sending logging messages to an email address via SMTP.
+
+
+.. class:: SMTPHandler(mailhost, fromaddr, toaddrs, subject[, credentials])
+
+ Returns a new instance of the :class:`SMTPHandler` class. The instance is
+ initialized with the from and to addresses and subject line of the email. The
+ *toaddrs* should be a list of strings. To specify a non-standard SMTP port, use
+ the (host, port) tuple format for the *mailhost* argument. If you use a string,
+ the standard SMTP port is used. If your SMTP server requires authentication, you
+ can specify a (username, password) tuple for the *credentials* argument.
+
+ .. versionchanged:: 2.6
+ *credentials* was added.
+
+
+.. method:: SMTPHandler.emit(record)
+
+ Formats the record and sends it to the specified addressees.
+
+
+.. method:: SMTPHandler.getSubject(record)
+
+ If you want to specify a subject line which is record-dependent, override this
+ method.
+
+
+MemoryHandler
+^^^^^^^^^^^^^
+
+The :class:`MemoryHandler` class, located in the :mod:`logging.handlers` module,
+supports buffering of logging records in memory, periodically flushing them to a
+:dfn:`target` handler. Flushing occurs whenever the buffer is full, or when an
+event of a certain severity or greater is seen.
+
+:class:`MemoryHandler` is a subclass of the more general
+:class:`BufferingHandler`, which is an abstract class. This buffers logging
+records in memory. Whenever each record is added to the buffer, a check is made
+by calling :meth:`shouldFlush` to see if the buffer should be flushed. If it
+should, then :meth:`flush` is expected to do the needful.
+
+
+.. class:: BufferingHandler(capacity)
+
+ Initializes the handler with a buffer of the specified capacity.
+
+
+.. method:: BufferingHandler.emit(record)
+
+ Appends the record to the buffer. If :meth:`shouldFlush` returns true, calls
+ :meth:`flush` to process the buffer.
+
+
+.. method:: BufferingHandler.flush()
+
+ You can override this to implement custom flushing behavior. This version just
+ zaps the buffer to empty.
+
+
+.. method:: BufferingHandler.shouldFlush(record)
+
+ Returns true if the buffer is up to capacity. This method can be overridden to
+ implement custom flushing strategies.
+
+
+.. class:: MemoryHandler(capacity[, flushLevel [, target]])
+
+ Returns a new instance of the :class:`MemoryHandler` class. The instance is
+ initialized with a buffer size of *capacity*. If *flushLevel* is not specified,
+ :const:`ERROR` is used. If no *target* is specified, the target will need to be
+ set using :meth:`setTarget` before this handler does anything useful.
+
+
+.. method:: MemoryHandler.close()
+
+ Calls :meth:`flush`, sets the target to :const:`None` and clears the buffer.
+
+
+.. method:: MemoryHandler.flush()
+
+ For a :class:`MemoryHandler`, flushing means just sending the buffered records
+ to the target, if there is one. Override if you want different behavior.
+
+
+.. method:: MemoryHandler.setTarget(target)
+
+ Sets the target handler for this handler.
+
+
+.. method:: MemoryHandler.shouldFlush(record)
+
+ Checks for buffer full or a record at the *flushLevel* or higher.
+
+
+HTTPHandler
+^^^^^^^^^^^
+
+The :class:`HTTPHandler` class, located in the :mod:`logging.handlers` module,
+supports sending logging messages to a Web server, using either ``GET`` or
+``POST`` semantics.
+
+
+.. class:: HTTPHandler(host, url[, method])
+
+ Returns a new instance of the :class:`HTTPHandler` class. The instance is
+ initialized with a host address, url and HTTP method. The *host* can be of the
+ form ``host:port``, should you need to use a specific port number. If no
+ *method* is specified, ``GET`` is used.
+
+
+.. method:: HTTPHandler.emit(record)
+
+ Sends the record to the Web server as an URL-encoded dictionary.
+
+
+Formatter Objects
+-----------------
+
+:class:`Formatter`\ s have the following attributes and methods. They are
+responsible for converting a :class:`LogRecord` to (usually) a string which can
+be interpreted by either a human or an external system. The base
+:class:`Formatter` allows a formatting string to be specified. If none is
+supplied, the default value of ``'%(message)s'`` is used.
+
+A Formatter can be initialized with a format string which makes use of knowledge
+of the :class:`LogRecord` attributes - such as the default value mentioned above
+making use of the fact that the user's message and arguments are pre-formatted
+into a :class:`LogRecord`'s *message* attribute. This format string contains
+standard python %-style mapping keys. See section :ref:`string-formatting`
+for more information on string formatting.
+
+Currently, the useful mapping keys in a :class:`LogRecord` are:
+
++-------------------------+-----------------------------------------------+
+| Format | Description |
++=========================+===============================================+
+| ``%(name)s`` | Name of the logger (logging channel). |
++-------------------------+-----------------------------------------------+
+| ``%(levelno)s`` | Numeric logging level for the message |
+| | (:const:`DEBUG`, :const:`INFO`, |
+| | :const:`WARNING`, :const:`ERROR`, |
+| | :const:`CRITICAL`). |
++-------------------------+-----------------------------------------------+
+| ``%(levelname)s`` | Text logging level for the message |
+| | (``'DEBUG'``, ``'INFO'``, ``'WARNING'``, |
+| | ``'ERROR'``, ``'CRITICAL'``). |
++-------------------------+-----------------------------------------------+
+| ``%(pathname)s`` | Full pathname of the source file where the |
+| | logging call was issued (if available). |
++-------------------------+-----------------------------------------------+
+| ``%(filename)s`` | Filename portion of pathname. |
++-------------------------+-----------------------------------------------+
+| ``%(module)s`` | Module (name portion of filename). |
++-------------------------+-----------------------------------------------+
+| ``%(funcName)s`` | Name of function containing the logging call. |
++-------------------------+-----------------------------------------------+
+| ``%(lineno)d`` | Source line number where the logging call was |
+| | issued (if available). |
++-------------------------+-----------------------------------------------+
+| ``%(created)f`` | Time when the :class:`LogRecord` was created |
+| | (as returned by :func:`time.time`). |
++-------------------------+-----------------------------------------------+
+| ``%(relativeCreated)d`` | Time in milliseconds when the LogRecord was |
+| | created, relative to the time the logging |
+| | module was loaded. |
++-------------------------+-----------------------------------------------+
+| ``%(asctime)s`` | Human-readable time when the |
+| | :class:`LogRecord` was created. By default |
+| | this is of the form "2003-07-08 16:49:45,896" |
+| | (the numbers after the comma are millisecond |
+| | portion of the time). |
++-------------------------+-----------------------------------------------+
+| ``%(msecs)d`` | Millisecond portion of the time when the |
+| | :class:`LogRecord` was created. |
++-------------------------+-----------------------------------------------+
+| ``%(thread)d`` | Thread ID (if available). |
++-------------------------+-----------------------------------------------+
+| ``%(threadName)s`` | Thread name (if available). |
++-------------------------+-----------------------------------------------+
+| ``%(process)d`` | Process ID (if available). |
++-------------------------+-----------------------------------------------+
+| ``%(message)s`` | The logged message, computed as ``msg % |
+| | args``. |
++-------------------------+-----------------------------------------------+
+
+.. versionchanged:: 2.5
+ *funcName* was added.
+
+
+.. class:: Formatter([fmt[, datefmt]])
+
+ Returns a new instance of the :class:`Formatter` class. The instance is
+ initialized with a format string for the message as a whole, as well as a format
+ string for the date/time portion of a message. If no *fmt* is specified,
+ ``'%(message)s'`` is used. If no *datefmt* is specified, the ISO8601 date format
+ is used.
+
+
+.. method:: Formatter.format(record)
+
+ The record's attribute dictionary is used as the operand to a string formatting
+ operation. Returns the resulting string. Before formatting the dictionary, a
+ couple of preparatory steps are carried out. The *message* attribute of the
+ record is computed using *msg* % *args*. If the formatting string contains
+ ``'(asctime)'``, :meth:`formatTime` is called to format the event time. If there
+ is exception information, it is formatted using :meth:`formatException` and
+ appended to the message.
+
+
+.. method:: Formatter.formatTime(record[, datefmt])
+
+ This method should be called from :meth:`format` by a formatter which wants to
+ make use of a formatted time. This method can be overridden in formatters to
+ provide for any specific requirement, but the basic behavior is as follows: if
+ *datefmt* (a string) is specified, it is used with :func:`time.strftime` to
+ format the creation time of the record. Otherwise, the ISO8601 format is used.
+ The resulting string is returned.
+
+
+.. method:: Formatter.formatException(exc_info)
+
+ Formats the specified exception information (a standard exception tuple as
+ returned by :func:`sys.exc_info`) as a string. This default implementation just
+ uses :func:`traceback.print_exception`. The resulting string is returned.
+
+
+Filter Objects
+--------------
+
+:class:`Filter`\ s can be used by :class:`Handler`\ s and :class:`Logger`\ s for
+more sophisticated filtering than is provided by levels. The base filter class
+only allows events which are below a certain point in the logger hierarchy. For
+example, a filter initialized with "A.B" will allow events logged by loggers
+"A.B", "A.B.C", "A.B.C.D", "A.B.D" etc. but not "A.BB", "B.A.B" etc. If
+initialized with the empty string, all events are passed.
+
+
+.. class:: Filter([name])
+
+ Returns an instance of the :class:`Filter` class. If *name* is specified, it
+ names a logger which, together with its children, will have its events allowed
+ through the filter. If no name is specified, allows every event.
+
+
+.. method:: Filter.filter(record)
+
+ Is the specified record to be logged? Returns zero for no, nonzero for yes. If
+ deemed appropriate, the record may be modified in-place by this method.
+
+
+LogRecord Objects
+-----------------
+
+:class:`LogRecord` instances are created every time something is logged. They
+contain all the information pertinent to the event being logged. The main
+information passed in is in msg and args, which are combined using msg % args to
+create the message field of the record. The record also includes information
+such as when the record was created, the source line where the logging call was
+made, and any exception information to be logged.
+
+
+.. class:: LogRecord(name, lvl, pathname, lineno, msg, args, exc_info [, func])
+
+ Returns an instance of :class:`LogRecord` initialized with interesting
+ information. The *name* is the logger name; *lvl* is the numeric level;
+ *pathname* is the absolute pathname of the source file in which the logging
+ call was made; *lineno* is the line number in that file where the logging
+ call is found; *msg* is the user-supplied message (a format string); *args*
+ is the tuple which, together with *msg*, makes up the user message; and
+ *exc_info* is the exception tuple obtained by calling :func:`sys.exc_info`
+ (or :const:`None`, if no exception information is available). The *func* is
+ the name of the function from which the logging call was made. If not
+ specified, it defaults to ``None``.
+
+ .. versionchanged:: 2.5
+ *func* was added.
+
+
+.. method:: LogRecord.getMessage()
+
+ Returns the message for this :class:`LogRecord` instance after merging any
+ user-supplied arguments with the message.
+
+
+Thread Safety
+-------------
+
+The logging module is intended to be thread-safe without any special work
+needing to be done by its clients. It achieves this though using threading
+locks; there is one lock to serialize access to the module's shared data, and
+each handler also creates a lock to serialize access to its underlying I/O.
+
+
+Configuration
+-------------
+
+
+.. _logging-config-api:
+
+Configuration functions
+^^^^^^^^^^^^^^^^^^^^^^^
+
+.. %
+
+The following functions configure the logging module. They are located in the
+:mod:`logging.config` module. Their use is optional --- you can configure the
+logging module using these functions or by making calls to the main API (defined
+in :mod:`logging` itself) and defining handlers which are declared either in
+:mod:`logging` or :mod:`logging.handlers`.
+
+
+.. function:: fileConfig(fname[, defaults])
+
+ Reads the logging configuration from a ConfigParser-format file named *fname*.
+ This function can be called several times from an application, allowing an end
+ user the ability to select from various pre-canned configurations (if the
+ developer provides a mechanism to present the choices and load the chosen
+ configuration). Defaults to be passed to ConfigParser can be specified in the
+ *defaults* argument.
+
+
+.. function:: listen([port])
+
+ Starts up a socket server on the specified port, and listens for new
+ configurations. If no port is specified, the module's default
+ :const:`DEFAULT_LOGGING_CONFIG_PORT` is used. Logging configurations will be
+ sent as a file suitable for processing by :func:`fileConfig`. Returns a
+ :class:`Thread` instance on which you can call :meth:`start` to start the
+ server, and which you can :meth:`join` when appropriate. To stop the server,
+ call :func:`stopListening`. To send a configuration to the socket, read in the
+ configuration file and send it to the socket as a string of bytes preceded by a
+ four-byte length packed in binary using struct.\ ``pack('>L', n)``.
+
+
+.. function:: stopListening()
+
+ Stops the listening server which was created with a call to :func:`listen`. This
+ is typically called before calling :meth:`join` on the return value from
+ :func:`listen`.
+
+
+.. _logging-config-fileformat:
+
+Configuration file format
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. %
+
+The configuration file format understood by :func:`fileConfig` is based on
+ConfigParser functionality. The file must contain sections called ``[loggers]``,
+``[handlers]`` and ``[formatters]`` which identify by name the entities of each
+type which are defined in the file. For each such entity, there is a separate
+section which identified how that entity is configured. Thus, for a logger named
+``log01`` in the ``[loggers]`` section, the relevant configuration details are
+held in a section ``[logger_log01]``. Similarly, a handler called ``hand01`` in
+the ``[handlers]`` section will have its configuration held in a section called
+``[handler_hand01]``, while a formatter called ``form01`` in the
+``[formatters]`` section will have its configuration specified in a section
+called ``[formatter_form01]``. The root logger configuration must be specified
+in a section called ``[logger_root]``.
+
+Examples of these sections in the file are given below. ::
+
+ [loggers]
+ keys=root,log02,log03,log04,log05,log06,log07
+
+ [handlers]
+ keys=hand01,hand02,hand03,hand04,hand05,hand06,hand07,hand08,hand09
+
+ [formatters]
+ keys=form01,form02,form03,form04,form05,form06,form07,form08,form09
+
+The root logger must specify a level and a list of handlers. An example of a
+root logger section is given below. ::
+
+ [logger_root]
+ level=NOTSET
+ handlers=hand01
+
+The ``level`` entry can be one of ``DEBUG, INFO, WARNING, ERROR, CRITICAL`` or
+``NOTSET``. For the root logger only, ``NOTSET`` means that all messages will be
+logged. Level values are :func:`eval`\ uated in the context of the ``logging``
+package's namespace.
+
+The ``handlers`` entry is a comma-separated list of handler names, which must
+appear in the ``[handlers]`` section. These names must appear in the
+``[handlers]`` section and have corresponding sections in the configuration
+file.
+
+For loggers other than the root logger, some additional information is required.
+This is illustrated by the following example. ::
+
+ [logger_parser]
+ level=DEBUG
+ handlers=hand01
+ propagate=1
+ qualname=compiler.parser
+
+The ``level`` and ``handlers`` entries are interpreted as for the root logger,
+except that if a non-root logger's level is specified as ``NOTSET``, the system
+consults loggers higher up the hierarchy to determine the effective level of the
+logger. The ``propagate`` entry is set to 1 to indicate that messages must
+propagate to handlers higher up the logger hierarchy from this logger, or 0 to
+indicate that messages are **not** propagated to handlers up the hierarchy. The
+``qualname`` entry is the hierarchical channel name of the logger, that is to
+say the name used by the application to get the logger.
+
+Sections which specify handler configuration are exemplified by the following.
+::
+
+ [handler_hand01]
+ class=StreamHandler
+ level=NOTSET
+ formatter=form01
+ args=(sys.stdout,)
+
+The ``class`` entry indicates the handler's class (as determined by :func:`eval`
+in the ``logging`` package's namespace). The ``level`` is interpreted as for
+loggers, and ``NOTSET`` is taken to mean "log everything".
+
+The ``formatter`` entry indicates the key name of the formatter for this
+handler. If blank, a default formatter (``logging._defaultFormatter``) is used.
+If a name is specified, it must appear in the ``[formatters]`` section and have
+a corresponding section in the configuration file.
+
+The ``args`` entry, when :func:`eval`\ uated in the context of the ``logging``
+package's namespace, is the list of arguments to the constructor for the handler
+class. Refer to the constructors for the relevant handlers, or to the examples
+below, to see how typical entries are constructed. ::
+
+ [handler_hand02]
+ class=FileHandler
+ level=DEBUG
+ formatter=form02
+ args=('python.log', 'w')
+
+ [handler_hand03]
+ class=handlers.SocketHandler
+ level=INFO
+ formatter=form03
+ args=('localhost', handlers.DEFAULT_TCP_LOGGING_PORT)
+
+ [handler_hand04]
+ class=handlers.DatagramHandler
+ level=WARN
+ formatter=form04
+ args=('localhost', handlers.DEFAULT_UDP_LOGGING_PORT)
+
+ [handler_hand05]
+ class=handlers.SysLogHandler
+ level=ERROR
+ formatter=form05
+ args=(('localhost', handlers.SYSLOG_UDP_PORT), handlers.SysLogHandler.LOG_USER)
+
+ [handler_hand06]
+ class=handlers.NTEventLogHandler
+ level=CRITICAL
+ formatter=form06
+ args=('Python Application', '', 'Application')
+
+ [handler_hand07]
+ class=handlers.SMTPHandler
+ level=WARN
+ formatter=form07
+ args=('localhost', 'from@abc', ['user1@abc', 'user2@xyz'], 'Logger Subject')
+
+ [handler_hand08]
+ class=handlers.MemoryHandler
+ level=NOTSET
+ formatter=form08
+ target=
+ args=(10, ERROR)
+
+ [handler_hand09]
+ class=handlers.HTTPHandler
+ level=NOTSET
+ formatter=form09
+ args=('localhost:9022', '/log', 'GET')
+
+Sections which specify formatter configuration are typified by the following. ::
+
+ [formatter_form01]
+ format=F1 %(asctime)s %(levelname)s %(message)s
+ datefmt=
+ class=logging.Formatter
+
+The ``format`` entry is the overall format string, and the ``datefmt`` entry is
+the :func:`strftime`\ -compatible date/time format string. If empty, the package
+substitutes ISO8601 format date/times, which is almost equivalent to specifying
+the date format string "The ISO8601 format also specifies milliseconds, which
+are appended to the result of using the above format string, with a comma
+separator. An example time in ISO8601 format is ``2003-01-23 00:29:50,411``.
+
+.. % Y-%m-%d %H:%M:%S".
+
+The ``class`` entry is optional. It indicates the name of the formatter's class
+(as a dotted module and class name.) This option is useful for instantiating a
+:class:`Formatter` subclass. Subclasses of :class:`Formatter` can present
+exception tracebacks in an expanded or condensed format.
+
diff --git a/Doc/library/mac.rst b/Doc/library/mac.rst
new file mode 100644
index 0000000000..791eb8132e
--- /dev/null
+++ b/Doc/library/mac.rst
@@ -0,0 +1,23 @@
+.. _mac-specific-services:
+
+*************************
+MacOS X specific services
+*************************
+
+This chapter describes modules that are only available on the Mac OS X platform.
+
+See the chapters :ref:`mac-scripting` and :ref:`undoc-mac-modules` for more
+modules, and the HOWTO :ref:`using-on-mac` for a general introduction to
+Mac-specific Python programming.
+
+
+.. toctree::
+
+ ic.rst
+ macos.rst
+ macostools.rst
+ easydialogs.rst
+ framework.rst
+ autogil.rst
+ carbon.rst
+ colorpicker.rst
diff --git a/Doc/library/macos.rst b/Doc/library/macos.rst
new file mode 100644
index 0000000000..543f8686cf
--- /dev/null
+++ b/Doc/library/macos.rst
@@ -0,0 +1,95 @@
+
+:mod:`MacOS` --- Access to Mac OS interpreter features
+======================================================
+
+.. module:: MacOS
+ :platform: Mac
+ :synopsis: Access to Mac OS-specific interpreter features.
+
+
+This module provides access to MacOS specific functionality in the Python
+interpreter, such as how the interpreter eventloop functions and the like. Use
+with care.
+
+Note the capitalization of the module name; this is a historical artifact.
+
+
+.. data:: runtimemodel
+
+ Always ``'macho'``, from Python 2.4 on. In earlier versions of Python the value
+ could also be ``'ppc'`` for the classic Mac OS 8 runtime model or ``'carbon'``
+ for the Mac OS 9 runtime model.
+
+
+.. data:: linkmodel
+
+ The way the interpreter has been linked. As extension modules may be
+ incompatible between linking models, packages could use this information to give
+ more decent error messages. The value is one of ``'static'`` for a statically
+ linked Python, ``'framework'`` for Python in a Mac OS X framework, ``'shared'``
+ for Python in a standard Unix shared library. Older Pythons could also have the
+ value ``'cfm'`` for Mac OS 9-compatible Python.
+
+
+.. exception:: Error
+
+ .. index:: module: macerrors
+
+ This exception is raised on MacOS generated errors, either from functions in
+ this module or from other mac-specific modules like the toolbox interfaces. The
+ arguments are the integer error code (the :cdata:`OSErr` value) and a textual
+ description of the error code. Symbolic names for all known error codes are
+ defined in the standard module :mod:`macerrors`.
+
+
+.. function:: GetErrorString(errno)
+
+ Return the textual description of MacOS error code *errno*.
+
+
+.. function:: DebugStr(message [, object])
+
+ On Mac OS X the string is simply printed to stderr (on older Mac OS systems more
+ elaborate functionality was available), but it provides a convenient location to
+ attach a breakpoint in a low-level debugger like :program:`gdb`.
+
+
+.. function:: SysBeep()
+
+ Ring the bell.
+
+
+.. function:: GetTicks()
+
+ Get the number of clock ticks (1/60th of a second) since system boot.
+
+
+.. function:: GetCreatorAndType(file)
+
+ Return the file creator and file type as two four-character strings. The *file*
+ parameter can be a pathname or an ``FSSpec`` or ``FSRef`` object.
+
+
+.. function:: SetCreatorAndType(file, creator, type)
+
+ Set the file creator and file type. The *file* parameter can be a pathname or an
+ ``FSSpec`` or ``FSRef`` object. *creator* and *type* must be four character
+ strings.
+
+
+.. function:: openrf(name [, mode])
+
+ Open the resource fork of a file. Arguments are the same as for the built-in
+ function :func:`open`. The object returned has file-like semantics, but it is
+ not a Python file object, so there may be subtle differences.
+
+
+.. function:: WMAvailable()
+
+ Checks whether the current process has access to the window manager. The method
+ will return ``False`` if the window manager is not available, for instance when
+ running on Mac OS X Server or when logged in via ssh, or when the current
+ interpreter is not running from a fullblown application bundle. A script runs
+ from an application bundle either when it has been started with
+ :program:`pythonw` instead of :program:`python` or when running as an applet.
+
diff --git a/Doc/library/macosa.rst b/Doc/library/macosa.rst
new file mode 100644
index 0000000000..67475eda5c
--- /dev/null
+++ b/Doc/library/macosa.rst
@@ -0,0 +1,92 @@
+
+.. _mac-scripting:
+
+*********************
+MacPython OSA Modules
+*********************
+
+This chapter describes the current implementation of the Open Scripting
+Architecure (OSA, also commonly referred to as AppleScript) for Python, allowing
+you to control scriptable applications from your Python program, and with a
+fairly pythonic interface. Development on this set of modules has stopped, and a
+replacement is expected for Python 2.5.
+
+For a description of the various components of AppleScript and OSA, and to get
+an understanding of the architecture and terminology, you should read Apple's
+documentation. The "Applescript Language Guide" explains the conceptual model
+and the terminology, and documents the standard suite. The "Open Scripting
+Architecture" document explains how to use OSA from an application programmers
+point of view. In the Apple Help Viewer these books are located in the Developer
+Documentation, Core Technologies section.
+
+As an example of scripting an application, the following piece of AppleScript
+will get the name of the frontmost :program:`Finder` window and print it::
+
+ tell application "Finder"
+ get name of window 1
+ end tell
+
+In Python, the following code fragment will do the same::
+
+ import Finder
+
+ f = Finder.Finder()
+ print f.get(f.window(1).name)
+
+As distributed the Python library includes packages that implement the standard
+suites, plus packages that interface to a small number of common applications.
+
+To send AppleEvents to an application you must first create the Python package
+interfacing to the terminology of the application (what :program:`Script Editor`
+calls the "Dictionary"). This can be done from within the :program:`PythonIDE`
+or by running the :file:`gensuitemodule.py` module as a standalone program from
+the command line.
+
+The generated output is a package with a number of modules, one for every suite
+used in the program plus an :mod:`__init__` module to glue it all together. The
+Python inheritance graph follows the AppleScript inheritance graph, so if a
+program's dictionary specifies that it includes support for the Standard Suite,
+but extends one or two verbs with extra arguments then the output suite will
+contain a module :mod:`Standard_Suite` that imports and re-exports everything
+from :mod:`StdSuites.Standard_Suite` but overrides the methods that have extra
+functionality. The output of :mod:`gensuitemodule` is pretty readable, and
+contains the documentation that was in the original AppleScript dictionary in
+Python docstrings, so reading it is a good source of documentation.
+
+The output package implements a main class with the same name as the package
+which contains all the AppleScript verbs as methods, with the direct object as
+the first argument and all optional parameters as keyword arguments. AppleScript
+classes are also implemented as Python classes, as are comparisons and all the
+other thingies.
+
+The main Python class implementing the verbs also allows access to the
+properties and elements declared in the AppleScript class "application". In the
+current release that is as far as the object orientation goes, so in the example
+above we need to use ``f.get(f.window(1).name)`` instead of the more Pythonic
+``f.window(1).name.get()``.
+
+If an AppleScript identifier is not a Python identifier the name is mangled
+according to a small number of rules:
+
+* spaces are replaced with underscores
+
+* other non-alphanumeric characters are replaced with ``_xx_`` where ``xx`` is
+ the hexadecimal character value
+
+* any Python reserved word gets an underscore appended
+
+Python also has support for creating scriptable applications in Python, but The
+following modules are relevant to MacPython AppleScript support:
+
+.. toctree::
+
+ gensuitemodule.rst
+ aetools.rst
+ aepack.rst
+ aetypes.rst
+ miniaeframe.rst
+
+
+In addition, support modules have been pre-generated for :mod:`Finder`,
+:mod:`Terminal`, :mod:`Explorer`, :mod:`Netscape`, :mod:`CodeWarrior`,
+:mod:`SystemEvents` and :mod:`StdSuites`.
diff --git a/Doc/library/macostools.rst b/Doc/library/macostools.rst
new file mode 100644
index 0000000000..275100e899
--- /dev/null
+++ b/Doc/library/macostools.rst
@@ -0,0 +1,115 @@
+
+:mod:`macostools` --- Convenience routines for file manipulation
+================================================================
+
+.. module:: macostools
+ :platform: Mac
+ :synopsis: Convenience routines for file manipulation.
+
+
+This module contains some convenience routines for file-manipulation on the
+Macintosh. All file parameters can be specified as pathnames, :class:`FSRef` or
+:class:`FSSpec` objects. This module expects a filesystem which supports forked
+files, so it should not be used on UFS partitions.
+
+The :mod:`macostools` module defines the following functions:
+
+
+.. function:: copy(src, dst[, createpath[, copytimes]])
+
+ Copy file *src* to *dst*. If *createpath* is non-zero the folders leading to
+ *dst* are created if necessary. The method copies data and resource fork and
+ some finder information (creator, type, flags) and optionally the creation,
+ modification and backup times (default is to copy them). Custom icons, comments
+ and icon position are not copied.
+
+
+.. function:: copytree(src, dst)
+
+ Recursively copy a file tree from *src* to *dst*, creating folders as needed.
+ *src* and *dst* should be specified as pathnames.
+
+
+.. function:: mkalias(src, dst)
+
+ Create a finder alias *dst* pointing to *src*.
+
+
+.. function:: touched(dst)
+
+ Tell the finder that some bits of finder-information such as creator or type for
+ file *dst* has changed. The file can be specified by pathname or fsspec. This
+ call should tell the finder to redraw the files icon.
+
+ .. deprecated:: 2.6
+ The function is a no-op on OS X.
+
+
+.. data:: BUFSIZ
+
+ The buffer size for ``copy``, default 1 megabyte.
+
+Note that the process of creating finder aliases is not specified in the Apple
+documentation. Hence, aliases created with :func:`mkalias` could conceivably
+have incompatible behaviour in some cases.
+
+
+:mod:`findertools` --- The :program:`finder`'s Apple Events interface
+=====================================================================
+
+.. module:: findertools
+ :platform: Mac
+ :synopsis: Wrappers around the finder's Apple Events interface.
+
+
+.. index:: single: AppleEvents
+
+This module contains routines that give Python programs access to some
+functionality provided by the finder. They are implemented as wrappers around
+the AppleEvent interface to the finder.
+
+All file and folder parameters can be specified either as full pathnames, or as
+:class:`FSRef` or :class:`FSSpec` objects.
+
+The :mod:`findertools` module defines the following functions:
+
+
+.. function:: launch(file)
+
+ Tell the finder to launch *file*. What launching means depends on the file:
+ applications are started, folders are opened and documents are opened in the
+ correct application.
+
+
+.. function:: Print(file)
+
+ Tell the finder to print a file. The behaviour is identical to selecting the
+ file and using the print command in the finder's file menu.
+
+
+.. function:: copy(file, destdir)
+
+ Tell the finder to copy a file or folder *file* to folder *destdir*. The
+ function returns an :class:`Alias` object pointing to the new file.
+
+
+.. function:: move(file, destdir)
+
+ Tell the finder to move a file or folder *file* to folder *destdir*. The
+ function returns an :class:`Alias` object pointing to the new file.
+
+
+.. function:: sleep()
+
+ Tell the finder to put the Macintosh to sleep, if your machine supports it.
+
+
+.. function:: restart()
+
+ Tell the finder to perform an orderly restart of the machine.
+
+
+.. function:: shutdown()
+
+ Tell the finder to perform an orderly shutdown of the machine.
+
diff --git a/Doc/library/macpath.rst b/Doc/library/macpath.rst
new file mode 100644
index 0000000000..66c54e5069
--- /dev/null
+++ b/Doc/library/macpath.rst
@@ -0,0 +1,17 @@
+
+:mod:`macpath` --- MacOS 9 path manipulation functions
+======================================================
+
+.. module:: macpath
+ :synopsis: MacOS 9 path manipulation functions.
+
+
+This module is the Mac OS 9 (and earlier) implementation of the :mod:`os.path`
+module. It can be used to manipulate old-style Macintosh pathnames on Mac OS X
+(or any other platform).
+
+The following functions are available in this module: :func:`normcase`,
+:func:`normpath`, :func:`isabs`, :func:`join`, :func:`split`, :func:`isdir`,
+:func:`isfile`, :func:`walk`, :func:`exists`. For other functions available in
+:mod:`os.path` dummy counterparts are available.
+
diff --git a/Doc/library/mailbox.rst b/Doc/library/mailbox.rst
new file mode 100644
index 0000000000..ce8dc59058
--- /dev/null
+++ b/Doc/library/mailbox.rst
@@ -0,0 +1,1679 @@
+
+:mod:`mailbox` --- Manipulate mailboxes in various formats
+==========================================================
+
+.. module:: mailbox
+ :synopsis: Manipulate mailboxes in various formats
+.. moduleauthor:: Gregory K. Johnson <gkj@gregorykjohnson.com>
+.. sectionauthor:: Gregory K. Johnson <gkj@gregorykjohnson.com>
+
+
+This module defines two classes, :class:`Mailbox` and :class:`Message`, for
+accessing and manipulating on-disk mailboxes and the messages they contain.
+:class:`Mailbox` offers a dictionary-like mapping from keys to messages.
+:class:`Message` extends the :mod:`email.Message` module's :class:`Message`
+class with format-specific state and behavior. Supported mailbox formats are
+Maildir, mbox, MH, Babyl, and MMDF.
+
+
+.. seealso::
+
+ Module :mod:`email`
+ Represent and manipulate messages.
+
+
+.. _mailbox-objects:
+
+:class:`Mailbox` objects
+------------------------
+
+
+.. class:: Mailbox
+
+ A mailbox, which may be inspected and modified.
+
+The :class:`Mailbox` class defines an interface and is not intended to be
+instantiated. Instead, format-specific subclasses should inherit from
+:class:`Mailbox` and your code should instantiate a particular subclass.
+
+The :class:`Mailbox` interface is dictionary-like, with small keys corresponding
+to messages. Keys are issued by the :class:`Mailbox` instance with which they
+will be used and are only meaningful to that :class:`Mailbox` instance. A key
+continues to identify a message even if the corresponding message is modified,
+such as by replacing it with another message.
+
+Messages may be added to a :class:`Mailbox` instance using the set-like method
+:meth:`add` and removed using a ``del`` statement or the set-like methods
+:meth:`remove` and :meth:`discard`.
+
+:class:`Mailbox` interface semantics differ from dictionary semantics in some
+noteworthy ways. Each time a message is requested, a new representation
+(typically a :class:`Message` instance) is generated based upon the current
+state of the mailbox. Similarly, when a message is added to a :class:`Mailbox`
+instance, the provided message representation's contents are copied. In neither
+case is a reference to the message representation kept by the :class:`Mailbox`
+instance.
+
+The default :class:`Mailbox` iterator iterates over message representations, not
+keys as the default dictionary iterator does. Moreover, modification of a
+mailbox during iteration is safe and well-defined. Messages added to the mailbox
+after an iterator is created will not be seen by the iterator. Messages removed
+from the mailbox before the iterator yields them will be silently skipped,
+though using a key from an iterator may result in a :exc:`KeyError` exception if
+the corresponding message is subsequently removed.
+
+.. warning::
+
+ Be very cautious when modifying mailboxes that might be simultaneously changed
+ by some other process. The safest mailbox format to use for such tasks is
+ Maildir; try to avoid using single-file formats such as mbox for concurrent
+ writing. If you're modifying a mailbox, you *must* lock it by calling the
+ :meth:`lock` and :meth:`unlock` methods *before* reading any messages in the
+ file or making any changes by adding or deleting a message. Failing to lock the
+ mailbox runs the risk of losing messages or corrupting the entire mailbox.
+
+:class:`Mailbox` instances have the following methods:
+
+
+.. method:: Mailbox.add(message)
+
+ Add *message* to the mailbox and return the key that has been assigned to it.
+
+ Parameter *message* may be a :class:`Message` instance, an
+ :class:`email.Message.Message` instance, a string, or a file-like object (which
+ should be open in text mode). If *message* is an instance of the appropriate
+ format-specific :class:`Message` subclass (e.g., if it's an :class:`mboxMessage`
+ instance and this is an :class:`mbox` instance), its format-specific information
+ is used. Otherwise, reasonable defaults for format-specific information are
+ used.
+
+
+.. method:: Mailbox.remove(key)
+ Mailbox.__delitem__(key)
+ Mailbox.discard(key)
+
+ Delete the message corresponding to *key* from the mailbox.
+
+ If no such message exists, a :exc:`KeyError` exception is raised if the method
+ was called as :meth:`remove` or :meth:`__delitem__` but no exception is raised
+ if the method was called as :meth:`discard`. The behavior of :meth:`discard` may
+ be preferred if the underlying mailbox format supports concurrent modification
+ by other processes.
+
+
+.. method:: Mailbox.__setitem__(key, message)
+
+ Replace the message corresponding to *key* with *message*. Raise a
+ :exc:`KeyError` exception if no message already corresponds to *key*.
+
+ As with :meth:`add`, parameter *message* may be a :class:`Message` instance, an
+ :class:`email.Message.Message` instance, a string, or a file-like object (which
+ should be open in text mode). If *message* is an instance of the appropriate
+ format-specific :class:`Message` subclass (e.g., if it's an :class:`mboxMessage`
+ instance and this is an :class:`mbox` instance), its format-specific information
+ is used. Otherwise, the format-specific information of the message that
+ currently corresponds to *key* is left unchanged.
+
+
+.. method:: Mailbox.iterkeys()
+ Mailbox.keys()
+
+ Return an iterator over all keys if called as :meth:`iterkeys` or return a list
+ of keys if called as :meth:`keys`.
+
+
+.. method:: Mailbox.itervalues()
+ Mailbox.__iter__()
+ Mailbox.values()
+
+ Return an iterator over representations of all messages if called as
+ :meth:`itervalues` or :meth:`__iter__` or return a list of such representations
+ if called as :meth:`values`. The messages are represented as instances of the
+ appropriate format-specific :class:`Message` subclass unless a custom message
+ factory was specified when the :class:`Mailbox` instance was initialized.
+
+ .. note::
+
+ The behavior of :meth:`__iter__` is unlike that of dictionaries, which iterate
+ over keys.
+
+
+.. method:: Mailbox.iteritems()
+ Mailbox.items()
+
+ Return an iterator over (*key*, *message*) pairs, where *key* is a key and
+ *message* is a message representation, if called as :meth:`iteritems` or return
+ a list of such pairs if called as :meth:`items`. The messages are represented as
+ instances of the appropriate format-specific :class:`Message` subclass unless a
+ custom message factory was specified when the :class:`Mailbox` instance was
+ initialized.
+
+
+.. method:: Mailbox.get(key[, default=None])
+ Mailbox.__getitem__(key)
+
+ Return a representation of the message corresponding to *key*. If no such
+ message exists, *default* is returned if the method was called as :meth:`get`
+ and a :exc:`KeyError` exception is raised if the method was called as
+ :meth:`__getitem__`. The message is represented as an instance of the
+ appropriate format-specific :class:`Message` subclass unless a custom message
+ factory was specified when the :class:`Mailbox` instance was initialized.
+
+
+.. method:: Mailbox.get_message(key)
+
+ Return a representation of the message corresponding to *key* as an instance of
+ the appropriate format-specific :class:`Message` subclass, or raise a
+ :exc:`KeyError` exception if no such message exists.
+
+
+.. method:: Mailbox.get_string(key)
+
+ Return a string representation of the message corresponding to *key*, or raise a
+ :exc:`KeyError` exception if no such message exists.
+
+
+.. method:: Mailbox.get_file(key)
+
+ Return a file-like representation of the message corresponding to *key*, or
+ raise a :exc:`KeyError` exception if no such message exists. The file-like
+ object behaves as if open in binary mode. This file should be closed once it is
+ no longer needed.
+
+ .. note::
+
+ Unlike other representations of messages, file-like representations are not
+ necessarily independent of the :class:`Mailbox` instance that created them or of
+ the underlying mailbox. More specific documentation is provided by each
+ subclass.
+
+
+.. method:: Mailbox.has_key(key)
+ Mailbox.__contains__(key)
+
+ Return ``True`` if *key* corresponds to a message, ``False`` otherwise.
+
+
+.. method:: Mailbox.__len__()
+
+ Return a count of messages in the mailbox.
+
+
+.. method:: Mailbox.clear()
+
+ Delete all messages from the mailbox.
+
+
+.. method:: Mailbox.pop(key[, default])
+
+ Return a representation of the message corresponding to *key* and delete the
+ message. If no such message exists, return *default* if it was supplied or else
+ raise a :exc:`KeyError` exception. The message is represented as an instance of
+ the appropriate format-specific :class:`Message` subclass unless a custom
+ message factory was specified when the :class:`Mailbox` instance was
+ initialized.
+
+
+.. method:: Mailbox.popitem()
+
+ Return an arbitrary (*key*, *message*) pair, where *key* is a key and *message*
+ is a message representation, and delete the corresponding message. If the
+ mailbox is empty, raise a :exc:`KeyError` exception. The message is represented
+ as an instance of the appropriate format-specific :class:`Message` subclass
+ unless a custom message factory was specified when the :class:`Mailbox` instance
+ was initialized.
+
+
+.. method:: Mailbox.update(arg)
+
+ Parameter *arg* should be a *key*-to-*message* mapping or an iterable of (*key*,
+ *message*) pairs. Updates the mailbox so that, for each given *key* and
+ *message*, the message corresponding to *key* is set to *message* as if by using
+ :meth:`__setitem__`. As with :meth:`__setitem__`, each *key* must already
+ correspond to a message in the mailbox or else a :exc:`KeyError` exception will
+ be raised, so in general it is incorrect for *arg* to be a :class:`Mailbox`
+ instance.
+
+ .. note::
+
+ Unlike with dictionaries, keyword arguments are not supported.
+
+
+.. method:: Mailbox.flush()
+
+ Write any pending changes to the filesystem. For some :class:`Mailbox`
+ subclasses, changes are always written immediately and :meth:`flush` does
+ nothing, but you should still make a habit of calling this method.
+
+
+.. method:: Mailbox.lock()
+
+ Acquire an exclusive advisory lock on the mailbox so that other processes know
+ not to modify it. An :exc:`ExternalClashError` is raised if the lock is not
+ available. The particular locking mechanisms used depend upon the mailbox
+ format. You should *always* lock the mailbox before making any modifications
+ to its contents.
+
+
+.. method:: Mailbox.unlock()
+
+ Release the lock on the mailbox, if any.
+
+
+.. method:: Mailbox.close()
+
+ Flush the mailbox, unlock it if necessary, and close any open files. For some
+ :class:`Mailbox` subclasses, this method does nothing.
+
+
+.. _mailbox-maildir:
+
+:class:`Maildir`
+^^^^^^^^^^^^^^^^
+
+
+.. class:: Maildir(dirname[, factory=rfc822.Message[, create=True]])
+
+ A subclass of :class:`Mailbox` for mailboxes in Maildir format. Parameter
+ *factory* is a callable object that accepts a file-like message representation
+ (which behaves as if opened in binary mode) and returns a custom representation.
+ If *factory* is ``None``, :class:`MaildirMessage` is used as the default message
+ representation. If *create* is ``True``, the mailbox is created if it does not
+ exist.
+
+ It is for historical reasons that *factory* defaults to :class:`rfc822.Message`
+ and that *dirname* is named as such rather than *path*. For a :class:`Maildir`
+ instance that behaves like instances of other :class:`Mailbox` subclasses, set
+ *factory* to ``None``.
+
+Maildir is a directory-based mailbox format invented for the qmail mail transfer
+agent and now widely supported by other programs. Messages in a Maildir mailbox
+are stored in separate files within a common directory structure. This design
+allows Maildir mailboxes to be accessed and modified by multiple unrelated
+programs without data corruption, so file locking is unnecessary.
+
+Maildir mailboxes contain three subdirectories, namely: :file:`tmp`,
+:file:`new`, and :file:`cur`. Messages are created momentarily in the
+:file:`tmp` subdirectory and then moved to the :file:`new` subdirectory to
+finalize delivery. A mail user agent may subsequently move the message to the
+:file:`cur` subdirectory and store information about the state of the message in
+a special "info" section appended to its file name.
+
+Folders of the style introduced by the Courier mail transfer agent are also
+supported. Any subdirectory of the main mailbox is considered a folder if
+``'.'`` is the first character in its name. Folder names are represented by
+:class:`Maildir` without the leading ``'.'``. Each folder is itself a Maildir
+mailbox but should not contain other folders. Instead, a logical nesting is
+indicated using ``'.'`` to delimit levels, e.g., "Archived.2005.07".
+
+.. note::
+
+ The Maildir specification requires the use of a colon (``':'``) in certain
+ message file names. However, some operating systems do not permit this character
+ in file names, If you wish to use a Maildir-like format on such an operating
+ system, you should specify another character to use instead. The exclamation
+ point (``'!'``) is a popular choice. For example::
+
+ import mailbox
+ mailbox.Maildir.colon = '!'
+
+ The :attr:`colon` attribute may also be set on a per-instance basis.
+
+:class:`Maildir` instances have all of the methods of :class:`Mailbox` in
+addition to the following:
+
+
+.. method:: Maildir.list_folders()
+
+ Return a list of the names of all folders.
+
+
+.. method:: Maildir.get_folder(folder)
+
+ Return a :class:`Maildir` instance representing the folder whose name is
+ *folder*. A :exc:`NoSuchMailboxError` exception is raised if the folder does not
+ exist.
+
+
+.. method:: Maildir.add_folder(folder)
+
+ Create a folder whose name is *folder* and return a :class:`Maildir` instance
+ representing it.
+
+
+.. method:: Maildir.remove_folder(folder)
+
+ Delete the folder whose name is *folder*. If the folder contains any messages, a
+ :exc:`NotEmptyError` exception will be raised and the folder will not be
+ deleted.
+
+
+.. method:: Maildir.clean()
+
+ Delete temporary files from the mailbox that have not been accessed in the last
+ 36 hours. The Maildir specification says that mail-reading programs should do
+ this occasionally.
+
+Some :class:`Mailbox` methods implemented by :class:`Maildir` deserve special
+remarks:
+
+
+.. method:: Maildir.add(message)
+ Maildir.__setitem__(key, message)
+ Maildir.update(arg)
+
+ .. warning::
+
+ These methods generate unique file names based upon the current process ID. When
+ using multiple threads, undetected name clashes may occur and cause corruption
+ of the mailbox unless threads are coordinated to avoid using these methods to
+ manipulate the same mailbox simultaneously.
+
+
+.. method:: Maildir.flush()
+
+ All changes to Maildir mailboxes are immediately applied, so this method does
+ nothing.
+
+
+.. method:: Maildir.lock()
+ Maildir.unlock()
+
+ Maildir mailboxes do not support (or require) locking, so these methods do
+ nothing.
+
+
+.. method:: Maildir.close()
+
+ :class:`Maildir` instances do not keep any open files and the underlying
+ mailboxes do not support locking, so this method does nothing.
+
+
+.. method:: Maildir.get_file(key)
+
+ Depending upon the host platform, it may not be possible to modify or remove the
+ underlying message while the returned file remains open.
+
+
+.. seealso::
+
+ `maildir man page from qmail <http://www.qmail.org/man/man5/maildir.html>`_
+ The original specification of the format.
+
+ `Using maildir format <http://cr.yp.to/proto/maildir.html>`_
+ Notes on Maildir by its inventor. Includes an updated name-creation scheme and
+ details on "info" semantics.
+
+ `maildir man page from Courier <http://www.courier-mta.org/?maildir.html>`_
+ Another specification of the format. Describes a common extension for supporting
+ folders.
+
+
+.. _mailbox-mbox:
+
+:class:`mbox`
+^^^^^^^^^^^^^
+
+
+.. class:: mbox(path[, factory=None[, create=True]])
+
+ A subclass of :class:`Mailbox` for mailboxes in mbox format. Parameter *factory*
+ is a callable object that accepts a file-like message representation (which
+ behaves as if opened in binary mode) and returns a custom representation. If
+ *factory* is ``None``, :class:`mboxMessage` is used as the default message
+ representation. If *create* is ``True``, the mailbox is created if it does not
+ exist.
+
+The mbox format is the classic format for storing mail on Unix systems. All
+messages in an mbox mailbox are stored in a single file with the beginning of
+each message indicated by a line whose first five characters are "From ".
+
+Several variations of the mbox format exist to address perceived shortcomings in
+the original. In the interest of compatibility, :class:`mbox` implements the
+original format, which is sometimes referred to as :dfn:`mboxo`. This means that
+the :mailheader:`Content-Length` header, if present, is ignored and that any
+occurrences of "From " at the beginning of a line in a message body are
+transformed to ">From " when storing the message, although occurences of ">From
+" are not transformed to "From " when reading the message.
+
+Some :class:`Mailbox` methods implemented by :class:`mbox` deserve special
+remarks:
+
+
+.. method:: mbox.get_file(key)
+
+ Using the file after calling :meth:`flush` or :meth:`close` on the :class:`mbox`
+ instance may yield unpredictable results or raise an exception.
+
+
+.. method:: mbox.lock()
+ mbox.unlock()
+
+ Three locking mechanisms are used---dot locking and, if available, the
+ :cfunc:`flock` and :cfunc:`lockf` system calls.
+
+
+.. seealso::
+
+ `mbox man page from qmail <http://www.qmail.org/man/man5/mbox.html>`_
+ A specification of the format and its variations.
+
+ `mbox man page from tin <http://www.tin.org/bin/man.cgi?section=5&topic=mbox>`_
+ Another specification of the format, with details on locking.
+
+ `Configuring Netscape Mail on Unix: Why The Content-Length Format is Bad <http://home.netscape.com/eng/mozilla/2.0/relnotes/demo/content-length.html>`_
+ An argument for using the original mbox format rather than a variation.
+
+ `"mbox" is a family of several mutually incompatible mailbox formats <http://homepages.tesco.net./~J.deBoynePollard/FGA/mail-mbox-formats.html>`_
+ A history of mbox variations.
+
+
+.. _mailbox-mh:
+
+:class:`MH`
+^^^^^^^^^^^
+
+
+.. class:: MH(path[, factory=None[, create=True]])
+
+ A subclass of :class:`Mailbox` for mailboxes in MH format. Parameter *factory*
+ is a callable object that accepts a file-like message representation (which
+ behaves as if opened in binary mode) and returns a custom representation. If
+ *factory* is ``None``, :class:`MHMessage` is used as the default message
+ representation. If *create* is ``True``, the mailbox is created if it does not
+ exist.
+
+MH is a directory-based mailbox format invented for the MH Message Handling
+System, a mail user agent. Each message in an MH mailbox resides in its own
+file. An MH mailbox may contain other MH mailboxes (called :dfn:`folders`) in
+addition to messages. Folders may be nested indefinitely. MH mailboxes also
+support :dfn:`sequences`, which are named lists used to logically group messages
+without moving them to sub-folders. Sequences are defined in a file called
+:file:`.mh_sequences` in each folder.
+
+The :class:`MH` class manipulates MH mailboxes, but it does not attempt to
+emulate all of :program:`mh`'s behaviors. In particular, it does not modify and
+is not affected by the :file:`context` or :file:`.mh_profile` files that are
+used by :program:`mh` to store its state and configuration.
+
+:class:`MH` instances have all of the methods of :class:`Mailbox` in addition to
+the following:
+
+
+.. method:: MH.list_folders()
+
+ Return a list of the names of all folders.
+
+
+.. method:: MH.get_folder(folder)
+
+ Return an :class:`MH` instance representing the folder whose name is *folder*. A
+ :exc:`NoSuchMailboxError` exception is raised if the folder does not exist.
+
+
+.. method:: MH.add_folder(folder)
+
+ Create a folder whose name is *folder* and return an :class:`MH` instance
+ representing it.
+
+
+.. method:: MH.remove_folder(folder)
+
+ Delete the folder whose name is *folder*. If the folder contains any messages, a
+ :exc:`NotEmptyError` exception will be raised and the folder will not be
+ deleted.
+
+
+.. method:: MH.get_sequences()
+
+ Return a dictionary of sequence names mapped to key lists. If there are no
+ sequences, the empty dictionary is returned.
+
+
+.. method:: MH.set_sequences(sequences)
+
+ Re-define the sequences that exist in the mailbox based upon *sequences*, a
+ dictionary of names mapped to key lists, like returned by :meth:`get_sequences`.
+
+
+.. method:: MH.pack()
+
+ Rename messages in the mailbox as necessary to eliminate gaps in numbering.
+ Entries in the sequences list are updated correspondingly.
+
+ .. note::
+
+ Already-issued keys are invalidated by this operation and should not be
+ subsequently used.
+
+Some :class:`Mailbox` methods implemented by :class:`MH` deserve special
+remarks:
+
+
+.. method:: MH.remove(key)
+ MH.__delitem__(key)
+ MH.discard(key)
+
+ These methods immediately delete the message. The MH convention of marking a
+ message for deletion by prepending a comma to its name is not used.
+
+
+.. method:: MH.lock()
+ MH.unlock()
+
+ Three locking mechanisms are used---dot locking and, if available, the
+ :cfunc:`flock` and :cfunc:`lockf` system calls. For MH mailboxes, locking the
+ mailbox means locking the :file:`.mh_sequences` file and, only for the duration
+ of any operations that affect them, locking individual message files.
+
+
+.. method:: MH.get_file(key)
+
+ Depending upon the host platform, it may not be possible to remove the
+ underlying message while the returned file remains open.
+
+
+.. method:: MH.flush()
+
+ All changes to MH mailboxes are immediately applied, so this method does
+ nothing.
+
+
+.. method:: MH.close()
+
+ :class:`MH` instances do not keep any open files, so this method is equivelant
+ to :meth:`unlock`.
+
+
+.. seealso::
+
+ `nmh - Message Handling System <http://www.nongnu.org/nmh/>`_
+ Home page of :program:`nmh`, an updated version of the original :program:`mh`.
+
+ `MH & nmh: Email for Users & Programmers <http://www.ics.uci.edu/~mh/book/>`_
+ A GPL-licensed book on :program:`mh` and :program:`nmh`, with some information
+ on the mailbox format.
+
+
+.. _mailbox-babyl:
+
+:class:`Babyl`
+^^^^^^^^^^^^^^
+
+
+.. class:: Babyl(path[, factory=None[, create=True]])
+
+ A subclass of :class:`Mailbox` for mailboxes in Babyl format. Parameter
+ *factory* is a callable object that accepts a file-like message representation
+ (which behaves as if opened in binary mode) and returns a custom representation.
+ If *factory* is ``None``, :class:`BabylMessage` is used as the default message
+ representation. If *create* is ``True``, the mailbox is created if it does not
+ exist.
+
+Babyl is a single-file mailbox format used by the Rmail mail user agent included
+with Emacs. The beginning of a message is indicated by a line containing the two
+characters Control-Underscore (``'\037'``) and Control-L (``'\014'``). The end
+of a message is indicated by the start of the next message or, in the case of
+the last message, a line containing a Control-Underscore (``'\037'``)
+character.
+
+Messages in a Babyl mailbox have two sets of headers, original headers and
+so-called visible headers. Visible headers are typically a subset of the
+original headers that have been reformatted or abridged to be more
+attractive. Each message in a Babyl mailbox also has an accompanying list of
+:dfn:`labels`, or short strings that record extra information about the message,
+and a list of all user-defined labels found in the mailbox is kept in the Babyl
+options section.
+
+:class:`Babyl` instances have all of the methods of :class:`Mailbox` in addition
+to the following:
+
+
+.. method:: Babyl.get_labels()
+
+ Return a list of the names of all user-defined labels used in the mailbox.
+
+ .. note::
+
+ The actual messages are inspected to determine which labels exist in the mailbox
+ rather than consulting the list of labels in the Babyl options section, but the
+ Babyl section is updated whenever the mailbox is modified.
+
+Some :class:`Mailbox` methods implemented by :class:`Babyl` deserve special
+remarks:
+
+
+.. method:: Babyl.get_file(key)
+
+ In Babyl mailboxes, the headers of a message are not stored contiguously with
+ the body of the message. To generate a file-like representation, the headers and
+ body are copied together into a :class:`StringIO` instance (from the
+ :mod:`StringIO` module), which has an API identical to that of a file. As a
+ result, the file-like object is truly independent of the underlying mailbox but
+ does not save memory compared to a string representation.
+
+
+.. method:: Babyl.lock()
+ Babyl.unlock()
+
+ Three locking mechanisms are used---dot locking and, if available, the
+ :cfunc:`flock` and :cfunc:`lockf` system calls.
+
+
+.. seealso::
+
+ `Format of Version 5 Babyl Files <http://quimby.gnus.org/notes/BABYL>`_
+ A specification of the Babyl format.
+
+ `Reading Mail with Rmail <http://www.gnu.org/software/emacs/manual/html_node/Rmail.html>`_
+ The Rmail manual, with some information on Babyl semantics.
+
+
+.. _mailbox-mmdf:
+
+:class:`MMDF`
+^^^^^^^^^^^^^
+
+
+.. class:: MMDF(path[, factory=None[, create=True]])
+
+ A subclass of :class:`Mailbox` for mailboxes in MMDF format. Parameter *factory*
+ is a callable object that accepts a file-like message representation (which
+ behaves as if opened in binary mode) and returns a custom representation. If
+ *factory* is ``None``, :class:`MMDFMessage` is used as the default message
+ representation. If *create* is ``True``, the mailbox is created if it does not
+ exist.
+
+MMDF is a single-file mailbox format invented for the Multichannel Memorandum
+Distribution Facility, a mail transfer agent. Each message is in the same form
+as an mbox message but is bracketed before and after by lines containing four
+Control-A (``'\001'``) characters. As with the mbox format, the beginning of
+each message is indicated by a line whose first five characters are "From ", but
+additional occurrences of "From " are not transformed to ">From " when storing
+messages because the extra message separator lines prevent mistaking such
+occurrences for the starts of subsequent messages.
+
+Some :class:`Mailbox` methods implemented by :class:`MMDF` deserve special
+remarks:
+
+
+.. method:: MMDF.get_file(key)
+
+ Using the file after calling :meth:`flush` or :meth:`close` on the :class:`MMDF`
+ instance may yield unpredictable results or raise an exception.
+
+
+.. method:: MMDF.lock()
+ MMDF.unlock()
+
+ Three locking mechanisms are used---dot locking and, if available, the
+ :cfunc:`flock` and :cfunc:`lockf` system calls.
+
+
+.. seealso::
+
+ `mmdf man page from tin <http://www.tin.org/bin/man.cgi?section=5&topic=mmdf>`_
+ A specification of MMDF format from the documentation of tin, a newsreader.
+
+ `MMDF <http://en.wikipedia.org/wiki/MMDF>`_
+ A Wikipedia article describing the Multichannel Memorandum Distribution
+ Facility.
+
+
+.. _mailbox-message-objects:
+
+:class:`Message` objects
+------------------------
+
+
+.. class:: Message([message])
+
+ A subclass of the :mod:`email.Message` module's :class:`Message`. Subclasses of
+ :class:`mailbox.Message` add mailbox-format-specific state and behavior.
+
+ If *message* is omitted, the new instance is created in a default, empty state.
+ If *message* is an :class:`email.Message.Message` instance, its contents are
+ copied; furthermore, any format-specific information is converted insofar as
+ possible if *message* is a :class:`Message` instance. If *message* is a string
+ or a file, it should contain an :rfc:`2822`\ -compliant message, which is read
+ and parsed.
+
+The format-specific state and behaviors offered by subclasses vary, but in
+general it is only the properties that are not specific to a particular mailbox
+that are supported (although presumably the properties are specific to a
+particular mailbox format). For example, file offsets for single-file mailbox
+formats and file names for directory-based mailbox formats are not retained,
+because they are only applicable to the original mailbox. But state such as
+whether a message has been read by the user or marked as important is retained,
+because it applies to the message itself.
+
+There is no requirement that :class:`Message` instances be used to represent
+messages retrieved using :class:`Mailbox` instances. In some situations, the
+time and memory required to generate :class:`Message` representations might not
+not acceptable. For such situations, :class:`Mailbox` instances also offer
+string and file-like representations, and a custom message factory may be
+specified when a :class:`Mailbox` instance is initialized.
+
+
+.. _mailbox-maildirmessage:
+
+:class:`MaildirMessage`
+^^^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: MaildirMessage([message])
+
+ A message with Maildir-specific behaviors. Parameter *message* has the same
+ meaning as with the :class:`Message` constructor.
+
+Typically, a mail user agent application moves all of the messages in the
+:file:`new` subdirectory to the :file:`cur` subdirectory after the first time
+the user opens and closes the mailbox, recording that the messages are old
+whether or not they've actually been read. Each message in :file:`cur` has an
+"info" section added to its file name to store information about its state.
+(Some mail readers may also add an "info" section to messages in :file:`new`.)
+The "info" section may take one of two forms: it may contain "2," followed by a
+list of standardized flags (e.g., "2,FR") or it may contain "1," followed by
+so-called experimental information. Standard flags for Maildir messages are as
+follows:
+
++------+---------+--------------------------------+
+| Flag | Meaning | Explanation |
++======+=========+================================+
+| D | Draft | Under composition |
++------+---------+--------------------------------+
+| F | Flagged | Marked as important |
++------+---------+--------------------------------+
+| P | Passed | Forwarded, resent, or bounced |
++------+---------+--------------------------------+
+| R | Replied | Replied to |
++------+---------+--------------------------------+
+| S | Seen | Read |
++------+---------+--------------------------------+
+| T | Trashed | Marked for subsequent deletion |
++------+---------+--------------------------------+
+
+:class:`MaildirMessage` instances offer the following methods:
+
+
+.. method:: MaildirMessage.get_subdir()
+
+ Return either "new" (if the message should be stored in the :file:`new`
+ subdirectory) or "cur" (if the message should be stored in the :file:`cur`
+ subdirectory).
+
+ .. note::
+
+ A message is typically moved from :file:`new` to :file:`cur` after its mailbox
+ has been accessed, whether or not the message is has been read. A message
+ ``msg`` has been read if ``"S" not in msg.get_flags()`` is ``True``.
+
+
+.. method:: MaildirMessage.set_subdir(subdir)
+
+ Set the subdirectory the message should be stored in. Parameter *subdir* must be
+ either "new" or "cur".
+
+
+.. method:: MaildirMessage.get_flags()
+
+ Return a string specifying the flags that are currently set. If the message
+ complies with the standard Maildir format, the result is the concatenation in
+ alphabetical order of zero or one occurrence of each of ``'D'``, ``'F'``,
+ ``'P'``, ``'R'``, ``'S'``, and ``'T'``. The empty string is returned if no flags
+ are set or if "info" contains experimental semantics.
+
+
+.. method:: MaildirMessage.set_flags(flags)
+
+ Set the flags specified by *flags* and unset all others.
+
+
+.. method:: MaildirMessage.add_flag(flag)
+
+ Set the flag(s) specified by *flag* without changing other flags. To add more
+ than one flag at a time, *flag* may be a string of more than one character. The
+ current "info" is overwritten whether or not it contains experimental
+ information rather than flags.
+
+
+.. method:: MaildirMessage.remove_flag(flag)
+
+ Unset the flag(s) specified by *flag* without changing other flags. To remove
+ more than one flag at a time, *flag* maybe a string of more than one character.
+ If "info" contains experimental information rather than flags, the current
+ "info" is not modified.
+
+
+.. method:: MaildirMessage.get_date()
+
+ Return the delivery date of the message as a floating-point number representing
+ seconds since the epoch.
+
+
+.. method:: MaildirMessage.set_date(date)
+
+ Set the delivery date of the message to *date*, a floating-point number
+ representing seconds since the epoch.
+
+
+.. method:: MaildirMessage.get_info()
+
+ Return a string containing the "info" for a message. This is useful for
+ accessing and modifying "info" that is experimental (i.e., not a list of flags).
+
+
+.. method:: MaildirMessage.set_info(info)
+
+ Set "info" to *info*, which should be a string.
+
+When a :class:`MaildirMessage` instance is created based upon an
+:class:`mboxMessage` or :class:`MMDFMessage` instance, the :mailheader:`Status`
+and :mailheader:`X-Status` headers are omitted and the following conversions
+take place:
+
++--------------------+----------------------------------------------+
+| Resulting state | :class:`mboxMessage` or :class:`MMDFMessage` |
+| | state |
++====================+==============================================+
+| "cur" subdirectory | O flag |
++--------------------+----------------------------------------------+
+| F flag | F flag |
++--------------------+----------------------------------------------+
+| R flag | A flag |
++--------------------+----------------------------------------------+
+| S flag | R flag |
++--------------------+----------------------------------------------+
+| T flag | D flag |
++--------------------+----------------------------------------------+
+
+When a :class:`MaildirMessage` instance is created based upon an
+:class:`MHMessage` instance, the following conversions take place:
+
++-------------------------------+--------------------------+
+| Resulting state | :class:`MHMessage` state |
++===============================+==========================+
+| "cur" subdirectory | "unseen" sequence |
++-------------------------------+--------------------------+
+| "cur" subdirectory and S flag | no "unseen" sequence |
++-------------------------------+--------------------------+
+| F flag | "flagged" sequence |
++-------------------------------+--------------------------+
+| R flag | "replied" sequence |
++-------------------------------+--------------------------+
+
+When a :class:`MaildirMessage` instance is created based upon a
+:class:`BabylMessage` instance, the following conversions take place:
+
++-------------------------------+-------------------------------+
+| Resulting state | :class:`BabylMessage` state |
++===============================+===============================+
+| "cur" subdirectory | "unseen" label |
++-------------------------------+-------------------------------+
+| "cur" subdirectory and S flag | no "unseen" label |
++-------------------------------+-------------------------------+
+| P flag | "forwarded" or "resent" label |
++-------------------------------+-------------------------------+
+| R flag | "answered" label |
++-------------------------------+-------------------------------+
+| T flag | "deleted" label |
++-------------------------------+-------------------------------+
+
+
+.. _mailbox-mboxmessage:
+
+:class:`mboxMessage`
+^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: mboxMessage([message])
+
+ A message with mbox-specific behaviors. Parameter *message* has the same meaning
+ as with the :class:`Message` constructor.
+
+Messages in an mbox mailbox are stored together in a single file. The sender's
+envelope address and the time of delivery are typically stored in a line
+beginning with "From " that is used to indicate the start of a message, though
+there is considerable variation in the exact format of this data among mbox
+implementations. Flags that indicate the state of the message, such as whether
+it has been read or marked as important, are typically stored in
+:mailheader:`Status` and :mailheader:`X-Status` headers.
+
+Conventional flags for mbox messages are as follows:
+
++------+----------+--------------------------------+
+| Flag | Meaning | Explanation |
++======+==========+================================+
+| R | Read | Read |
++------+----------+--------------------------------+
+| O | Old | Previously detected by MUA |
++------+----------+--------------------------------+
+| D | Deleted | Marked for subsequent deletion |
++------+----------+--------------------------------+
+| F | Flagged | Marked as important |
++------+----------+--------------------------------+
+| A | Answered | Replied to |
++------+----------+--------------------------------+
+
+The "R" and "O" flags are stored in the :mailheader:`Status` header, and the
+"D", "F", and "A" flags are stored in the :mailheader:`X-Status` header. The
+flags and headers typically appear in the order mentioned.
+
+:class:`mboxMessage` instances offer the following methods:
+
+
+.. method:: mboxMessage.get_from()
+
+ Return a string representing the "From " line that marks the start of the
+ message in an mbox mailbox. The leading "From " and the trailing newline are
+ excluded.
+
+
+.. method:: mboxMessage.set_from(from_[, time_=None])
+
+ Set the "From " line to *from_*, which should be specified without a leading
+ "From " or trailing newline. For convenience, *time_* may be specified and will
+ be formatted appropriately and appended to *from_*. If *time_* is specified, it
+ should be a :class:`struct_time` instance, a tuple suitable for passing to
+ :meth:`time.strftime`, or ``True`` (to use :meth:`time.gmtime`).
+
+
+.. method:: mboxMessage.get_flags()
+
+ Return a string specifying the flags that are currently set. If the message
+ complies with the conventional format, the result is the concatenation in the
+ following order of zero or one occurrence of each of ``'R'``, ``'O'``, ``'D'``,
+ ``'F'``, and ``'A'``.
+
+
+.. method:: mboxMessage.set_flags(flags)
+
+ Set the flags specified by *flags* and unset all others. Parameter *flags*
+ should be the concatenation in any order of zero or more occurrences of each of
+ ``'R'``, ``'O'``, ``'D'``, ``'F'``, and ``'A'``.
+
+
+.. method:: mboxMessage.add_flag(flag)
+
+ Set the flag(s) specified by *flag* without changing other flags. To add more
+ than one flag at a time, *flag* may be a string of more than one character.
+
+
+.. method:: mboxMessage.remove_flag(flag)
+
+ Unset the flag(s) specified by *flag* without changing other flags. To remove
+ more than one flag at a time, *flag* maybe a string of more than one character.
+
+When an :class:`mboxMessage` instance is created based upon a
+:class:`MaildirMessage` instance, a "From " line is generated based upon the
+:class:`MaildirMessage` instance's delivery date, and the following conversions
+take place:
+
++-----------------+-------------------------------+
+| Resulting state | :class:`MaildirMessage` state |
++=================+===============================+
+| R flag | S flag |
++-----------------+-------------------------------+
+| O flag | "cur" subdirectory |
++-----------------+-------------------------------+
+| D flag | T flag |
++-----------------+-------------------------------+
+| F flag | F flag |
++-----------------+-------------------------------+
+| A flag | R flag |
++-----------------+-------------------------------+
+
+When an :class:`mboxMessage` instance is created based upon an
+:class:`MHMessage` instance, the following conversions take place:
+
++-------------------+--------------------------+
+| Resulting state | :class:`MHMessage` state |
++===================+==========================+
+| R flag and O flag | no "unseen" sequence |
++-------------------+--------------------------+
+| O flag | "unseen" sequence |
++-------------------+--------------------------+
+| F flag | "flagged" sequence |
++-------------------+--------------------------+
+| A flag | "replied" sequence |
++-------------------+--------------------------+
+
+When an :class:`mboxMessage` instance is created based upon a
+:class:`BabylMessage` instance, the following conversions take place:
+
++-------------------+-----------------------------+
+| Resulting state | :class:`BabylMessage` state |
++===================+=============================+
+| R flag and O flag | no "unseen" label |
++-------------------+-----------------------------+
+| O flag | "unseen" label |
++-------------------+-----------------------------+
+| D flag | "deleted" label |
++-------------------+-----------------------------+
+| A flag | "answered" label |
++-------------------+-----------------------------+
+
+When a :class:`Message` instance is created based upon an :class:`MMDFMessage`
+instance, the "From " line is copied and all flags directly correspond:
+
++-----------------+----------------------------+
+| Resulting state | :class:`MMDFMessage` state |
++=================+============================+
+| R flag | R flag |
++-----------------+----------------------------+
+| O flag | O flag |
++-----------------+----------------------------+
+| D flag | D flag |
++-----------------+----------------------------+
+| F flag | F flag |
++-----------------+----------------------------+
+| A flag | A flag |
++-----------------+----------------------------+
+
+
+.. _mailbox-mhmessage:
+
+:class:`MHMessage`
+^^^^^^^^^^^^^^^^^^
+
+
+.. class:: MHMessage([message])
+
+ A message with MH-specific behaviors. Parameter *message* has the same meaning
+ as with the :class:`Message` constructor.
+
+MH messages do not support marks or flags in the traditional sense, but they do
+support sequences, which are logical groupings of arbitrary messages. Some mail
+reading programs (although not the standard :program:`mh` and :program:`nmh`)
+use sequences in much the same way flags are used with other formats, as
+follows:
+
++----------+------------------------------------------+
+| Sequence | Explanation |
++==========+==========================================+
+| unseen | Not read, but previously detected by MUA |
++----------+------------------------------------------+
+| replied | Replied to |
++----------+------------------------------------------+
+| flagged | Marked as important |
++----------+------------------------------------------+
+
+:class:`MHMessage` instances offer the following methods:
+
+
+.. method:: MHMessage.get_sequences()
+
+ Return a list of the names of sequences that include this message.
+
+
+.. method:: MHMessage.set_sequences(sequences)
+
+ Set the list of sequences that include this message.
+
+
+.. method:: MHMessage.add_sequence(sequence)
+
+ Add *sequence* to the list of sequences that include this message.
+
+
+.. method:: MHMessage.remove_sequence(sequence)
+
+ Remove *sequence* from the list of sequences that include this message.
+
+When an :class:`MHMessage` instance is created based upon a
+:class:`MaildirMessage` instance, the following conversions take place:
+
++--------------------+-------------------------------+
+| Resulting state | :class:`MaildirMessage` state |
++====================+===============================+
+| "unseen" sequence | no S flag |
++--------------------+-------------------------------+
+| "replied" sequence | R flag |
++--------------------+-------------------------------+
+| "flagged" sequence | F flag |
++--------------------+-------------------------------+
+
+When an :class:`MHMessage` instance is created based upon an
+:class:`mboxMessage` or :class:`MMDFMessage` instance, the :mailheader:`Status`
+and :mailheader:`X-Status` headers are omitted and the following conversions
+take place:
+
++--------------------+----------------------------------------------+
+| Resulting state | :class:`mboxMessage` or :class:`MMDFMessage` |
+| | state |
++====================+==============================================+
+| "unseen" sequence | no R flag |
++--------------------+----------------------------------------------+
+| "replied" sequence | A flag |
++--------------------+----------------------------------------------+
+| "flagged" sequence | F flag |
++--------------------+----------------------------------------------+
+
+When an :class:`MHMessage` instance is created based upon a
+:class:`BabylMessage` instance, the following conversions take place:
+
++--------------------+-----------------------------+
+| Resulting state | :class:`BabylMessage` state |
++====================+=============================+
+| "unseen" sequence | "unseen" label |
++--------------------+-----------------------------+
+| "replied" sequence | "answered" label |
++--------------------+-----------------------------+
+
+
+.. _mailbox-babylmessage:
+
+:class:`BabylMessage`
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: BabylMessage([message])
+
+ A message with Babyl-specific behaviors. Parameter *message* has the same
+ meaning as with the :class:`Message` constructor.
+
+Certain message labels, called :dfn:`attributes`, are defined by convention to
+have special meanings. The attributes are as follows:
+
++-----------+------------------------------------------+
+| Label | Explanation |
++===========+==========================================+
+| unseen | Not read, but previously detected by MUA |
++-----------+------------------------------------------+
+| deleted | Marked for subsequent deletion |
++-----------+------------------------------------------+
+| filed | Copied to another file or mailbox |
++-----------+------------------------------------------+
+| answered | Replied to |
++-----------+------------------------------------------+
+| forwarded | Forwarded |
++-----------+------------------------------------------+
+| edited | Modified by the user |
++-----------+------------------------------------------+
+| resent | Resent |
++-----------+------------------------------------------+
+
+By default, Rmail displays only visible headers. The :class:`BabylMessage`
+class, though, uses the original headers because they are more complete. Visible
+headers may be accessed explicitly if desired.
+
+:class:`BabylMessage` instances offer the following methods:
+
+
+.. method:: BabylMessage.get_labels()
+
+ Return a list of labels on the message.
+
+
+.. method:: BabylMessage.set_labels(labels)
+
+ Set the list of labels on the message to *labels*.
+
+
+.. method:: BabylMessage.add_label(label)
+
+ Add *label* to the list of labels on the message.
+
+
+.. method:: BabylMessage.remove_label(label)
+
+ Remove *label* from the list of labels on the message.
+
+
+.. method:: BabylMessage.get_visible()
+
+ Return an :class:`Message` instance whose headers are the message's visible
+ headers and whose body is empty.
+
+
+.. method:: BabylMessage.set_visible(visible)
+
+ Set the message's visible headers to be the same as the headers in *message*.
+ Parameter *visible* should be a :class:`Message` instance, an
+ :class:`email.Message.Message` instance, a string, or a file-like object (which
+ should be open in text mode).
+
+
+.. method:: BabylMessage.update_visible()
+
+ When a :class:`BabylMessage` instance's original headers are modified, the
+ visible headers are not automatically modified to correspond. This method
+ updates the visible headers as follows: each visible header with a corresponding
+ original header is set to the value of the original header, each visible header
+ without a corresponding original header is removed, and any of
+ :mailheader:`Date`, :mailheader:`From`, :mailheader:`Reply-To`,
+ :mailheader:`To`, :mailheader:`CC`, and :mailheader:`Subject` that are present
+ in the original headers but not the visible headers are added to the visible
+ headers.
+
+When a :class:`BabylMessage` instance is created based upon a
+:class:`MaildirMessage` instance, the following conversions take place:
+
++-------------------+-------------------------------+
+| Resulting state | :class:`MaildirMessage` state |
++===================+===============================+
+| "unseen" label | no S flag |
++-------------------+-------------------------------+
+| "deleted" label | T flag |
++-------------------+-------------------------------+
+| "answered" label | R flag |
++-------------------+-------------------------------+
+| "forwarded" label | P flag |
++-------------------+-------------------------------+
+
+When a :class:`BabylMessage` instance is created based upon an
+:class:`mboxMessage` or :class:`MMDFMessage` instance, the :mailheader:`Status`
+and :mailheader:`X-Status` headers are omitted and the following conversions
+take place:
+
++------------------+----------------------------------------------+
+| Resulting state | :class:`mboxMessage` or :class:`MMDFMessage` |
+| | state |
++==================+==============================================+
+| "unseen" label | no R flag |
++------------------+----------------------------------------------+
+| "deleted" label | D flag |
++------------------+----------------------------------------------+
+| "answered" label | A flag |
++------------------+----------------------------------------------+
+
+When a :class:`BabylMessage` instance is created based upon an
+:class:`MHMessage` instance, the following conversions take place:
+
++------------------+--------------------------+
+| Resulting state | :class:`MHMessage` state |
++==================+==========================+
+| "unseen" label | "unseen" sequence |
++------------------+--------------------------+
+| "answered" label | "replied" sequence |
++------------------+--------------------------+
+
+
+.. _mailbox-mmdfmessage:
+
+:class:`MMDFMessage`
+^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: MMDFMessage([message])
+
+ A message with MMDF-specific behaviors. Parameter *message* has the same meaning
+ as with the :class:`Message` constructor.
+
+As with message in an mbox mailbox, MMDF messages are stored with the sender's
+address and the delivery date in an initial line beginning with "From ".
+Likewise, flags that indicate the state of the message are typically stored in
+:mailheader:`Status` and :mailheader:`X-Status` headers.
+
+Conventional flags for MMDF messages are identical to those of mbox message and
+are as follows:
+
++------+----------+--------------------------------+
+| Flag | Meaning | Explanation |
++======+==========+================================+
+| R | Read | Read |
++------+----------+--------------------------------+
+| O | Old | Previously detected by MUA |
++------+----------+--------------------------------+
+| D | Deleted | Marked for subsequent deletion |
++------+----------+--------------------------------+
+| F | Flagged | Marked as important |
++------+----------+--------------------------------+
+| A | Answered | Replied to |
++------+----------+--------------------------------+
+
+The "R" and "O" flags are stored in the :mailheader:`Status` header, and the
+"D", "F", and "A" flags are stored in the :mailheader:`X-Status` header. The
+flags and headers typically appear in the order mentioned.
+
+:class:`MMDFMessage` instances offer the following methods, which are identical
+to those offered by :class:`mboxMessage`:
+
+
+.. method:: MMDFMessage.get_from()
+
+ Return a string representing the "From " line that marks the start of the
+ message in an mbox mailbox. The leading "From " and the trailing newline are
+ excluded.
+
+
+.. method:: MMDFMessage.set_from(from_[, time_=None])
+
+ Set the "From " line to *from_*, which should be specified without a leading
+ "From " or trailing newline. For convenience, *time_* may be specified and will
+ be formatted appropriately and appended to *from_*. If *time_* is specified, it
+ should be a :class:`struct_time` instance, a tuple suitable for passing to
+ :meth:`time.strftime`, or ``True`` (to use :meth:`time.gmtime`).
+
+
+.. method:: MMDFMessage.get_flags()
+
+ Return a string specifying the flags that are currently set. If the message
+ complies with the conventional format, the result is the concatenation in the
+ following order of zero or one occurrence of each of ``'R'``, ``'O'``, ``'D'``,
+ ``'F'``, and ``'A'``.
+
+
+.. method:: MMDFMessage.set_flags(flags)
+
+ Set the flags specified by *flags* and unset all others. Parameter *flags*
+ should be the concatenation in any order of zero or more occurrences of each of
+ ``'R'``, ``'O'``, ``'D'``, ``'F'``, and ``'A'``.
+
+
+.. method:: MMDFMessage.add_flag(flag)
+
+ Set the flag(s) specified by *flag* without changing other flags. To add more
+ than one flag at a time, *flag* may be a string of more than one character.
+
+
+.. method:: MMDFMessage.remove_flag(flag)
+
+ Unset the flag(s) specified by *flag* without changing other flags. To remove
+ more than one flag at a time, *flag* maybe a string of more than one character.
+
+When an :class:`MMDFMessage` instance is created based upon a
+:class:`MaildirMessage` instance, a "From " line is generated based upon the
+:class:`MaildirMessage` instance's delivery date, and the following conversions
+take place:
+
++-----------------+-------------------------------+
+| Resulting state | :class:`MaildirMessage` state |
++=================+===============================+
+| R flag | S flag |
++-----------------+-------------------------------+
+| O flag | "cur" subdirectory |
++-----------------+-------------------------------+
+| D flag | T flag |
++-----------------+-------------------------------+
+| F flag | F flag |
++-----------------+-------------------------------+
+| A flag | R flag |
++-----------------+-------------------------------+
+
+When an :class:`MMDFMessage` instance is created based upon an
+:class:`MHMessage` instance, the following conversions take place:
+
++-------------------+--------------------------+
+| Resulting state | :class:`MHMessage` state |
++===================+==========================+
+| R flag and O flag | no "unseen" sequence |
++-------------------+--------------------------+
+| O flag | "unseen" sequence |
++-------------------+--------------------------+
+| F flag | "flagged" sequence |
++-------------------+--------------------------+
+| A flag | "replied" sequence |
++-------------------+--------------------------+
+
+When an :class:`MMDFMessage` instance is created based upon a
+:class:`BabylMessage` instance, the following conversions take place:
+
++-------------------+-----------------------------+
+| Resulting state | :class:`BabylMessage` state |
++===================+=============================+
+| R flag and O flag | no "unseen" label |
++-------------------+-----------------------------+
+| O flag | "unseen" label |
++-------------------+-----------------------------+
+| D flag | "deleted" label |
++-------------------+-----------------------------+
+| A flag | "answered" label |
++-------------------+-----------------------------+
+
+When an :class:`MMDFMessage` instance is created based upon an
+:class:`mboxMessage` instance, the "From " line is copied and all flags directly
+correspond:
+
++-----------------+----------------------------+
+| Resulting state | :class:`mboxMessage` state |
++=================+============================+
+| R flag | R flag |
++-----------------+----------------------------+
+| O flag | O flag |
++-----------------+----------------------------+
+| D flag | D flag |
++-----------------+----------------------------+
+| F flag | F flag |
++-----------------+----------------------------+
+| A flag | A flag |
++-----------------+----------------------------+
+
+
+Exceptions
+----------
+
+The following exception classes are defined in the :mod:`mailbox` module:
+
+
+.. class:: Error()
+
+ The based class for all other module-specific exceptions.
+
+
+.. class:: NoSuchMailboxError()
+
+ Raised when a mailbox is expected but is not found, such as when instantiating a
+ :class:`Mailbox` subclass with a path that does not exist (and with the *create*
+ parameter set to ``False``), or when opening a folder that does not exist.
+
+
+.. class:: NotEmptyErrorError()
+
+ Raised when a mailbox is not empty but is expected to be, such as when deleting
+ a folder that contains messages.
+
+
+.. class:: ExternalClashError()
+
+ Raised when some mailbox-related condition beyond the control of the program
+ causes it to be unable to proceed, such as when failing to acquire a lock that
+ another program already holds a lock, or when a uniquely-generated file name
+ already exists.
+
+
+.. class:: FormatError()
+
+ Raised when the data in a file cannot be parsed, such as when an :class:`MH`
+ instance attempts to read a corrupted :file:`.mh_sequences` file.
+
+
+.. _mailbox-deprecated:
+
+Deprecated classes and methods
+------------------------------
+
+Older versions of the :mod:`mailbox` module do not support modification of
+mailboxes, such as adding or removing message, and do not provide classes to
+represent format-specific message properties. For backward compatibility, the
+older mailbox classes are still available, but the newer classes should be used
+in preference to them.
+
+Older mailbox objects support only iteration and provide a single public method:
+
+
+.. method:: oldmailbox.next()
+
+ Return the next message in the mailbox, created with the optional *factory*
+ argument passed into the mailbox object's constructor. By default this is an
+ :class:`rfc822.Message` object (see the :mod:`rfc822` module). Depending on the
+ mailbox implementation the *fp* attribute of this object may be a true file
+ object or a class instance simulating a file object, taking care of things like
+ message boundaries if multiple mail messages are contained in a single file,
+ etc. If no more messages are available, this method returns ``None``.
+
+Most of the older mailbox classes have names that differ from the current
+mailbox class names, except for :class:`Maildir`. For this reason, the new
+:class:`Maildir` class defines a :meth:`next` method and its constructor differs
+slightly from those of the other new mailbox classes.
+
+The older mailbox classes whose names are not the same as their newer
+counterparts are as follows:
+
+
+.. class:: UnixMailbox(fp[, factory])
+
+ Access to a classic Unix-style mailbox, where all messages are contained in a
+ single file and separated by ``From`` (a.k.a. ``From_``) lines. The file object
+ *fp* points to the mailbox file. The optional *factory* parameter is a callable
+ that should create new message objects. *factory* is called with one argument,
+ *fp* by the :meth:`next` method of the mailbox object. The default is the
+ :class:`rfc822.Message` class (see the :mod:`rfc822` module -- and the note
+ below).
+
+ .. note::
+
+ For reasons of this module's internal implementation, you will probably want to
+ open the *fp* object in binary mode. This is especially important on Windows.
+
+ For maximum portability, messages in a Unix-style mailbox are separated by any
+ line that begins exactly with the string ``'From '`` (note the trailing space)
+ if preceded by exactly two newlines. Because of the wide-range of variations in
+ practice, nothing else on the ``From_`` line should be considered. However, the
+ current implementation doesn't check for the leading two newlines. This is
+ usually fine for most applications.
+
+ The :class:`UnixMailbox` class implements a more strict version of ``From_``
+ line checking, using a regular expression that usually correctly matched
+ ``From_`` delimiters. It considers delimiter line to be separated by ``From
+ name time`` lines. For maximum portability, use the
+ :class:`PortableUnixMailbox` class instead. This class is identical to
+ :class:`UnixMailbox` except that individual messages are separated by only
+ ``From`` lines.
+
+ For more information, see `Configuring Netscape Mail on Unix: Why the
+ Content-Length Format is Bad
+ <http://home.netscape.com/eng/mozilla/2.0/relnotes/demo/content-length.html>`_.
+
+
+.. class:: PortableUnixMailbox(fp[, factory])
+
+ A less-strict version of :class:`UnixMailbox`, which considers only the ``From``
+ at the beginning of the line separating messages. The "*name* *time*" portion
+ of the From line is ignored, to protect against some variations that are
+ observed in practice. This works since lines in the message which begin with
+ ``'From '`` are quoted by mail handling software at delivery-time.
+
+
+.. class:: MmdfMailbox(fp[, factory])
+
+ Access an MMDF-style mailbox, where all messages are contained in a single file
+ and separated by lines consisting of 4 control-A characters. The file object
+ *fp* points to the mailbox file. Optional *factory* is as with the
+ :class:`UnixMailbox` class.
+
+
+.. class:: MHMailbox(dirname[, factory])
+
+ Access an MH mailbox, a directory with each message in a separate file with a
+ numeric name. The name of the mailbox directory is passed in *dirname*.
+ *factory* is as with the :class:`UnixMailbox` class.
+
+
+.. class:: BabylMailbox(fp[, factory])
+
+ Access a Babyl mailbox, which is similar to an MMDF mailbox. In Babyl format,
+ each message has two sets of headers, the *original* headers and the *visible*
+ headers. The original headers appear before a line containing only ``'*** EOOH
+ ***'`` (End-Of-Original-Headers) and the visible headers appear after the
+ ``EOOH`` line. Babyl-compliant mail readers will show you only the visible
+ headers, and :class:`BabylMailbox` objects will return messages containing only
+ the visible headers. You'll have to do your own parsing of the mailbox file to
+ get at the original headers. Mail messages start with the EOOH line and end
+ with a line containing only ``'\037\014'``. *factory* is as with the
+ :class:`UnixMailbox` class.
+
+If you wish to use the older mailbox classes with the :mod:`email` module rather
+than the deprecated :mod:`rfc822` module, you can do so as follows::
+
+ import email
+ import email.Errors
+ import mailbox
+
+ def msgfactory(fp):
+ try:
+ return email.message_from_file(fp)
+ except email.Errors.MessageParseError:
+ # Don't return None since that will
+ # stop the mailbox iterator
+ return ''
+
+ mbox = mailbox.UnixMailbox(fp, msgfactory)
+
+Alternatively, if you know your mailbox contains only well-formed MIME messages,
+you can simplify this to::
+
+ import email
+ import mailbox
+
+ mbox = mailbox.UnixMailbox(fp, email.message_from_file)
+
+
+.. _mailbox-examples:
+
+Examples
+--------
+
+A simple example of printing the subjects of all messages in a mailbox that seem
+interesting::
+
+ import mailbox
+ for message in mailbox.mbox('~/mbox'):
+ subject = message['subject'] # Could possibly be None.
+ if subject and 'python' in subject.lower():
+ print subject
+
+To copy all mail from a Babyl mailbox to an MH mailbox, converting all of the
+format-specific information that can be converted::
+
+ import mailbox
+ destination = mailbox.MH('~/Mail')
+ destination.lock()
+ for message in mailbox.Babyl('~/RMAIL'):
+ destination.add(MHMessage(message))
+ destination.flush()
+ destination.unlock()
+
+This example sorts mail from several mailing lists into different mailboxes,
+being careful to avoid mail corruption due to concurrent modification by other
+programs, mail loss due to interruption of the program, or premature termination
+due to malformed messages in the mailbox::
+
+ import mailbox
+ import email.Errors
+
+ list_names = ('python-list', 'python-dev', 'python-bugs')
+
+ boxes = dict((name, mailbox.mbox('~/email/%s' % name)) for name in list_names)
+ inbox = mailbox.Maildir('~/Maildir', factory=None)
+
+ for key in inbox.iterkeys():
+ try:
+ message = inbox[key]
+ except email.Errors.MessageParseError:
+ continue # The message is malformed. Just leave it.
+
+ for name in list_names:
+ list_id = message['list-id']
+ if list_id and name in list_id:
+ # Get mailbox to use
+ box = boxes[name]
+
+ # Write copy to disk before removing original.
+ # If there's a crash, you might duplicate a message, but
+ # that's better than losing a message completely.
+ box.lock()
+ box.add(message)
+ box.flush()
+ box.unlock()
+
+ # Remove original message
+ inbox.lock()
+ inbox.discard(key)
+ inbox.flush()
+ inbox.unlock()
+ break # Found destination, so stop looking.
+
+ for box in boxes.itervalues():
+ box.close()
+
diff --git a/Doc/library/mailcap.rst b/Doc/library/mailcap.rst
new file mode 100644
index 0000000000..8dcb1ec612
--- /dev/null
+++ b/Doc/library/mailcap.rst
@@ -0,0 +1,74 @@
+:mod:`mailcap` --- Mailcap file handling
+========================================
+
+.. module:: mailcap
+ :synopsis: Mailcap file handling.
+
+
+
+Mailcap files are used to configure how MIME-aware applications such as mail
+readers and Web browsers react to files with different MIME types. (The name
+"mailcap" is derived from the phrase "mail capability".) For example, a mailcap
+file might contain a line like ``video/mpeg; xmpeg %s``. Then, if the user
+encounters an email message or Web document with the MIME type
+:mimetype:`video/mpeg`, ``%s`` will be replaced by a filename (usually one
+belonging to a temporary file) and the :program:`xmpeg` program can be
+automatically started to view the file.
+
+The mailcap format is documented in :rfc:`1524`, "A User Agent Configuration
+Mechanism For Multimedia Mail Format Information," but is not an Internet
+standard. However, mailcap files are supported on most Unix systems.
+
+
+.. function:: findmatch(caps, MIMEtype[, key[, filename[, plist]]])
+
+ Return a 2-tuple; the first element is a string containing the command line to
+ be executed (which can be passed to :func:`os.system`), and the second element
+ is the mailcap entry for a given MIME type. If no matching MIME type can be
+ found, ``(None, None)`` is returned.
+
+ *key* is the name of the field desired, which represents the type of activity to
+ be performed; the default value is 'view', since in the most common case you
+ simply want to view the body of the MIME-typed data. Other possible values
+ might be 'compose' and 'edit', if you wanted to create a new body of the given
+ MIME type or alter the existing body data. See :rfc:`1524` for a complete list
+ of these fields.
+
+ *filename* is the filename to be substituted for ``%s`` in the command line; the
+ default value is ``'/dev/null'`` which is almost certainly not what you want, so
+ usually you'll override it by specifying a filename.
+
+ *plist* can be a list containing named parameters; the default value is simply
+ an empty list. Each entry in the list must be a string containing the parameter
+ name, an equals sign (``'='``), and the parameter's value. Mailcap entries can
+ contain named parameters like ``%{foo}``, which will be replaced by the value
+ of the parameter named 'foo'. For example, if the command line ``showpartial
+ %{id} %{number} %{total}`` was in a mailcap file, and *plist* was set to
+ ``['id=1', 'number=2', 'total=3']``, the resulting command line would be
+ ``'showpartial 1 2 3'``.
+
+ In a mailcap file, the "test" field can optionally be specified to test some
+ external condition (such as the machine architecture, or the window system in
+ use) to determine whether or not the mailcap line applies. :func:`findmatch`
+ will automatically check such conditions and skip the entry if the check fails.
+
+
+.. function:: getcaps()
+
+ Returns a dictionary mapping MIME types to a list of mailcap file entries. This
+ dictionary must be passed to the :func:`findmatch` function. An entry is stored
+ as a list of dictionaries, but it shouldn't be necessary to know the details of
+ this representation.
+
+ The information is derived from all of the mailcap files found on the system.
+ Settings in the user's mailcap file :file:`$HOME/.mailcap` will override
+ settings in the system mailcap files :file:`/etc/mailcap`,
+ :file:`/usr/etc/mailcap`, and :file:`/usr/local/etc/mailcap`.
+
+An example usage::
+
+ >>> import mailcap
+ >>> d=mailcap.getcaps()
+ >>> mailcap.findmatch(d, 'video/mpeg', filename='/tmp/tmp1223')
+ ('xmpeg /tmp/tmp1223', {'view': 'xmpeg %s'})
+
diff --git a/Doc/library/markup.rst b/Doc/library/markup.rst
new file mode 100644
index 0000000000..dd0dd8f08f
--- /dev/null
+++ b/Doc/library/markup.rst
@@ -0,0 +1,44 @@
+
+.. _markup:
+
+**********************************
+Structured Markup Processing Tools
+**********************************
+
+Python supports a variety of modules to work with various forms of structured
+data markup. This includes modules to work with the Standard Generalized Markup
+Language (SGML) and the Hypertext Markup Language (HTML), and several interfaces
+for working with the Extensible Markup Language (XML).
+
+It is important to note that modules in the :mod:`xml` package require that
+there be at least one SAX-compliant XML parser available. Starting with Python
+2.3, the Expat parser is included with Python, so the :mod:`xml.parsers.expat`
+module will always be available. You may still want to be aware of the `PyXML
+add-on package <http://pyxml.sourceforge.net/>`_; that package provides an
+extended set of XML libraries for Python.
+
+The documentation for the :mod:`xml.dom` and :mod:`xml.sax` packages are the
+definition of the Python bindings for the DOM and SAX interfaces.
+
+
+.. toctree::
+
+ htmlparser.rst
+ sgmllib.rst
+ htmllib.rst
+ pyexpat.rst
+ xml.dom.rst
+ xml.dom.minidom.rst
+ xml.dom.pulldom.rst
+ xml.sax.rst
+ xml.sax.handler.rst
+ xml.sax.utils.rst
+ xml.sax.reader.rst
+ xml.etree.elementtree.rst
+
+.. seealso::
+
+ `Python/XML Libraries <http://pyxml.sourceforge.net/>`_
+ Home page for the PyXML package, containing an extension of :mod:`xml` package
+ bundled with Python.
+
diff --git a/Doc/library/marshal.rst b/Doc/library/marshal.rst
new file mode 100644
index 0000000000..010ebc3c77
--- /dev/null
+++ b/Doc/library/marshal.rst
@@ -0,0 +1,127 @@
+
+:mod:`marshal` --- Internal Python object serialization
+=======================================================
+
+.. module:: marshal
+ :synopsis: Convert Python objects to streams of bytes and back (with different
+ constraints).
+
+
+This module contains functions that can read and write Python values in a binary
+format. The format is specific to Python, but independent of machine
+architecture issues (e.g., you can write a Python value to a file on a PC,
+transport the file to a Sun, and read it back there). Details of the format are
+undocumented on purpose; it may change between Python versions (although it
+rarely does). [#]_
+
+.. index::
+ module: pickle
+ module: shelve
+ object: code
+
+This is not a general "persistence" module. For general persistence and
+transfer of Python objects through RPC calls, see the modules :mod:`pickle` and
+:mod:`shelve`. The :mod:`marshal` module exists mainly to support reading and
+writing the "pseudo-compiled" code for Python modules of :file:`.pyc` files.
+Therefore, the Python maintainers reserve the right to modify the marshal format
+in backward incompatible ways should the need arise. If you're serializing and
+de-serializing Python objects, use the :mod:`pickle` module instead.
+
+.. warning::
+
+ The :mod:`marshal` module is not intended to be secure against erroneous or
+ maliciously constructed data. Never unmarshal data received from an
+ untrusted or unauthenticated source.
+
+Not all Python object types are supported; in general, only objects whose value
+is independent from a particular invocation of Python can be written and read by
+this module. The following types are supported: ``None``, integers, long
+integers, floating point numbers, strings, Unicode objects, tuples, lists,
+dictionaries, and code objects, where it should be understood that tuples, lists
+and dictionaries are only supported as long as the values contained therein are
+themselves supported; and recursive lists and dictionaries should not be written
+(they will cause infinite loops).
+
+**Caveat:** On machines where C's ``long int`` type has more than 32 bits (such
+as the DEC Alpha), it is possible to create plain Python integers that are
+longer than 32 bits. If such an integer is marshaled and read back in on a
+machine where C's ``long int`` type has only 32 bits, a Python long integer
+object is returned instead. While of a different type, the numeric value is the
+same. (This behavior is new in Python 2.2. In earlier versions, all but the
+least-significant 32 bits of the value were lost, and a warning message was
+printed.)
+
+There are functions that read/write files as well as functions operating on
+strings.
+
+The module defines these functions:
+
+
+.. function:: dump(value, file[, version])
+
+ Write the value on the open file. The value must be a supported type. The
+ file must be an open file object such as ``sys.stdout`` or returned by
+ :func:`open` or :func:`os.popen`. It must be opened in binary mode (``'wb'``
+ or ``'w+b'``).
+
+ If the value has (or contains an object that has) an unsupported type, a
+ :exc:`ValueError` exception is raised --- but garbage data will also be written
+ to the file. The object will not be properly read back by :func:`load`.
+
+ .. versionadded:: 2.4
+ The *version* argument indicates the data format that ``dump`` should use
+ (see below).
+
+
+.. function:: load(file)
+
+ Read one value from the open file and return it. If no valid value is read
+ (e.g. because the data has a different Python version's incompatible marshal
+ format), raise :exc:`EOFError`, :exc:`ValueError` or :exc:`TypeError`. The
+ file must be an open file object opened in binary mode (``'rb'`` or
+ ``'r+b'``).
+
+ .. warning::
+
+ If an object containing an unsupported type was marshalled with :func:`dump`,
+ :func:`load` will substitute ``None`` for the unmarshallable type.
+
+
+.. function:: dumps(value[, version])
+
+ Return the string that would be written to a file by ``dump(value, file)``. The
+ value must be a supported type. Raise a :exc:`ValueError` exception if value
+ has (or contains an object that has) an unsupported type.
+
+ .. versionadded:: 2.4
+ The *version* argument indicates the data format that ``dumps`` should use
+ (see below).
+
+
+.. function:: loads(string)
+
+ Convert the string to a value. If no valid value is found, raise
+ :exc:`EOFError`, :exc:`ValueError` or :exc:`TypeError`. Extra characters in the
+ string are ignored.
+
+
+In addition, the following constants are defined:
+
+.. data:: version
+
+ Indicates the format that the module uses. Version 0 is the historical format,
+ version 1 (added in Python 2.4) shares interned strings and version 2 (added in
+ Python 2.5) uses a binary format for floating point numbers. The current version
+ is 2.
+
+ .. versionadded:: 2.4
+
+
+.. rubric:: Footnotes
+
+.. [#] The name of this module stems from a bit of terminology used by the designers of
+ Modula-3 (amongst others), who use the term "marshalling" for shipping of data
+ around in a self-contained form. Strictly speaking, "to marshal" means to
+ convert some data from internal to external form (in an RPC buffer for instance)
+ and "unmarshalling" for the reverse process.
+
diff --git a/Doc/library/math.rst b/Doc/library/math.rst
new file mode 100644
index 0000000000..17c75d3f82
--- /dev/null
+++ b/Doc/library/math.rst
@@ -0,0 +1,227 @@
+
+:mod:`math` --- Mathematical functions
+======================================
+
+.. module:: math
+ :synopsis: Mathematical functions (sin() etc.).
+
+
+This module is always available. It provides access to the mathematical
+functions defined by the C standard.
+
+These functions cannot be used with complex numbers; use the functions of the
+same name from the :mod:`cmath` module if you require support for complex
+numbers. The distinction between functions which support complex numbers and
+those which don't is made since most users do not want to learn quite as much
+mathematics as required to understand complex numbers. Receiving an exception
+instead of a complex result allows earlier detection of the unexpected complex
+number used as a parameter, so that the programmer can determine how and why it
+was generated in the first place.
+
+The following functions are provided by this module. Except when explicitly
+noted otherwise, all return values are floats.
+
+Number-theoretic and representation functions:
+
+
+.. function:: ceil(x)
+
+ Return the ceiling of *x* as a float, the smallest integer value greater than or
+ equal to *x*.
+
+
+.. function:: fabs(x)
+
+ Return the absolute value of *x*.
+
+
+.. function:: floor(x)
+
+ Return the floor of *x* as a float, the largest integer value less than or equal
+ to *x*.
+
+
+.. function:: fmod(x, y)
+
+ Return ``fmod(x, y)``, as defined by the platform C library. Note that the
+ Python expression ``x % y`` may not return the same result. The intent of the C
+ standard is that ``fmod(x, y)`` be exactly (mathematically; to infinite
+ precision) equal to ``x - n*y`` for some integer *n* such that the result has
+ the same sign as *x* and magnitude less than ``abs(y)``. Python's ``x % y``
+ returns a result with the sign of *y* instead, and may not be exactly computable
+ for float arguments. For example, ``fmod(-1e-100, 1e100)`` is ``-1e-100``, but
+ the result of Python's ``-1e-100 % 1e100`` is ``1e100-1e-100``, which cannot be
+ represented exactly as a float, and rounds to the surprising ``1e100``. For
+ this reason, function :func:`fmod` is generally preferred when working with
+ floats, while Python's ``x % y`` is preferred when working with integers.
+
+
+.. function:: frexp(x)
+
+ Return the mantissa and exponent of *x* as the pair ``(m, e)``. *m* is a float
+ and *e* is an integer such that ``x == m * 2**e`` exactly. If *x* is zero,
+ returns ``(0.0, 0)``, otherwise ``0.5 <= abs(m) < 1``. This is used to "pick
+ apart" the internal representation of a float in a portable way.
+
+
+.. function:: ldexp(x, i)
+
+ Return ``x * (2**i)``. This is essentially the inverse of function
+ :func:`frexp`.
+
+
+.. function:: modf(x)
+
+ Return the fractional and integer parts of *x*. Both results carry the sign of
+ *x*, and both are floats.
+
+Note that :func:`frexp` and :func:`modf` have a different call/return pattern
+than their C equivalents: they take a single argument and return a pair of
+values, rather than returning their second return value through an 'output
+parameter' (there is no such thing in Python).
+
+For the :func:`ceil`, :func:`floor`, and :func:`modf` functions, note that *all*
+floating-point numbers of sufficiently large magnitude are exact integers.
+Python floats typically carry no more than 53 bits of precision (the same as the
+platform C double type), in which case any float *x* with ``abs(x) >= 2**52``
+necessarily has no fractional bits.
+
+Power and logarithmic functions:
+
+
+.. function:: exp(x)
+
+ Return ``e**x``.
+
+
+.. function:: log(x[, base])
+
+ Return the logarithm of *x* to the given *base*. If the *base* is not specified,
+ return the natural logarithm of *x* (that is, the logarithm to base *e*).
+
+ .. versionchanged:: 2.3
+ *base* argument added.
+
+
+.. function:: log10(x)
+
+ Return the base-10 logarithm of *x*.
+
+
+.. function:: pow(x, y)
+
+ Return ``x**y``.
+
+
+.. function:: sqrt(x)
+
+ Return the square root of *x*.
+
+Trigonometric functions:
+
+
+.. function:: acos(x)
+
+ Return the arc cosine of *x*, in radians.
+
+
+.. function:: asin(x)
+
+ Return the arc sine of *x*, in radians.
+
+
+.. function:: atan(x)
+
+ Return the arc tangent of *x*, in radians.
+
+
+.. function:: atan2(y, x)
+
+ Return ``atan(y / x)``, in radians. The result is between ``-pi`` and ``pi``.
+ The vector in the plane from the origin to point ``(x, y)`` makes this angle
+ with the positive X axis. The point of :func:`atan2` is that the signs of both
+ inputs are known to it, so it can compute the correct quadrant for the angle.
+ For example, ``atan(1``) and ``atan2(1, 1)`` are both ``pi/4``, but ``atan2(-1,
+ -1)`` is ``-3*pi/4``.
+
+
+.. function:: cos(x)
+
+ Return the cosine of *x* radians.
+
+
+.. function:: hypot(x, y)
+
+ Return the Euclidean norm, ``sqrt(x*x + y*y)``. This is the length of the vector
+ from the origin to point ``(x, y)``.
+
+
+.. function:: sin(x)
+
+ Return the sine of *x* radians.
+
+
+.. function:: tan(x)
+
+ Return the tangent of *x* radians.
+
+Angular conversion:
+
+
+.. function:: degrees(x)
+
+ Converts angle *x* from radians to degrees.
+
+
+.. function:: radians(x)
+
+ Converts angle *x* from degrees to radians.
+
+Hyperbolic functions:
+
+
+.. function:: cosh(x)
+
+ Return the hyperbolic cosine of *x*.
+
+
+.. function:: sinh(x)
+
+ Return the hyperbolic sine of *x*.
+
+
+.. function:: tanh(x)
+
+ Return the hyperbolic tangent of *x*.
+
+The module also defines two mathematical constants:
+
+
+.. data:: pi
+
+ The mathematical constant *pi*.
+
+
+.. data:: e
+
+ The mathematical constant *e*.
+
+.. note::
+
+ The :mod:`math` module consists mostly of thin wrappers around the platform C
+ math library functions. Behavior in exceptional cases is loosely specified
+ by the C standards, and Python inherits much of its math-function
+ error-reporting behavior from the platform C implementation. As a result,
+ the specific exceptions raised in error cases (and even whether some
+ arguments are considered to be exceptional at all) are not defined in any
+ useful cross-platform or cross-release way. For example, whether
+ ``math.log(0)`` returns ``-Inf`` or raises :exc:`ValueError` or
+ :exc:`OverflowError` isn't defined, and in cases where ``math.log(0)`` raises
+ :exc:`OverflowError`, ``math.log(0L)`` may raise :exc:`ValueError` instead.
+
+
+.. seealso::
+
+ Module :mod:`cmath`
+ Complex number versions of many of these functions.
+
diff --git a/Doc/library/mhlib.rst b/Doc/library/mhlib.rst
new file mode 100644
index 0000000000..15d2b05ff0
--- /dev/null
+++ b/Doc/library/mhlib.rst
@@ -0,0 +1,205 @@
+
+:mod:`mhlib` --- Access to MH mailboxes
+=======================================
+
+.. module:: mhlib
+ :synopsis: Manipulate MH mailboxes from Python.
+
+
+.. % LaTeX'ized from the comments in the module by Skip Montanaro
+.. % <skip@mojam.com>.
+
+The :mod:`mhlib` module provides a Python interface to MH folders and their
+contents.
+
+The module contains three basic classes, :class:`MH`, which represents a
+particular collection of folders, :class:`Folder`, which represents a single
+folder, and :class:`Message`, which represents a single message.
+
+
+.. class:: MH([path[, profile]])
+
+ :class:`MH` represents a collection of MH folders.
+
+
+.. class:: Folder(mh, name)
+
+ The :class:`Folder` class represents a single folder and its messages.
+
+
+.. class:: Message(folder, number[, name])
+
+ :class:`Message` objects represent individual messages in a folder. The Message
+ class is derived from :class:`mimetools.Message`.
+
+
+.. _mh-objects:
+
+MH Objects
+----------
+
+:class:`MH` instances have the following methods:
+
+
+.. method:: MH.error(format[, ...])
+
+ Print an error message -- can be overridden.
+
+
+.. method:: MH.getprofile(key)
+
+ Return a profile entry (``None`` if not set).
+
+
+.. method:: MH.getpath()
+
+ Return the mailbox pathname.
+
+
+.. method:: MH.getcontext()
+
+ Return the current folder name.
+
+
+.. method:: MH.setcontext(name)
+
+ Set the current folder name.
+
+
+.. method:: MH.listfolders()
+
+ Return a list of top-level folders.
+
+
+.. method:: MH.listallfolders()
+
+ Return a list of all folders.
+
+
+.. method:: MH.listsubfolders(name)
+
+ Return a list of direct subfolders of the given folder.
+
+
+.. method:: MH.listallsubfolders(name)
+
+ Return a list of all subfolders of the given folder.
+
+
+.. method:: MH.makefolder(name)
+
+ Create a new folder.
+
+
+.. method:: MH.deletefolder(name)
+
+ Delete a folder -- must have no subfolders.
+
+
+.. method:: MH.openfolder(name)
+
+ Return a new open folder object.
+
+
+.. _mh-folder-objects:
+
+Folder Objects
+--------------
+
+:class:`Folder` instances represent open folders and have the following methods:
+
+
+.. method:: Folder.error(format[, ...])
+
+ Print an error message -- can be overridden.
+
+
+.. method:: Folder.getfullname()
+
+ Return the folder's full pathname.
+
+
+.. method:: Folder.getsequencesfilename()
+
+ Return the full pathname of the folder's sequences file.
+
+
+.. method:: Folder.getmessagefilename(n)
+
+ Return the full pathname of message *n* of the folder.
+
+
+.. method:: Folder.listmessages()
+
+ Return a list of messages in the folder (as numbers).
+
+
+.. method:: Folder.getcurrent()
+
+ Return the current message number.
+
+
+.. method:: Folder.setcurrent(n)
+
+ Set the current message number to *n*.
+
+
+.. method:: Folder.parsesequence(seq)
+
+ Parse msgs syntax into list of messages.
+
+
+.. method:: Folder.getlast()
+
+ Get last message, or ``0`` if no messages are in the folder.
+
+
+.. method:: Folder.setlast(n)
+
+ Set last message (internal use only).
+
+
+.. method:: Folder.getsequences()
+
+ Return dictionary of sequences in folder. The sequence names are used as keys,
+ and the values are the lists of message numbers in the sequences.
+
+
+.. method:: Folder.putsequences(dict)
+
+ Return dictionary of sequences in folder name: list.
+
+
+.. method:: Folder.removemessages(list)
+
+ Remove messages in list from folder.
+
+
+.. method:: Folder.refilemessages(list, tofolder)
+
+ Move messages in list to other folder.
+
+
+.. method:: Folder.movemessage(n, tofolder, ton)
+
+ Move one message to a given destination in another folder.
+
+
+.. method:: Folder.copymessage(n, tofolder, ton)
+
+ Copy one message to a given destination in another folder.
+
+
+.. _mh-message-objects:
+
+Message Objects
+---------------
+
+The :class:`Message` class adds one method to those of
+:class:`mimetools.Message`:
+
+
+.. method:: Message.openmessage(n)
+
+ Return a new open message object (costs a file descriptor).
+
diff --git a/Doc/library/mimetools.rst b/Doc/library/mimetools.rst
new file mode 100644
index 0000000000..603bec6ef2
--- /dev/null
+++ b/Doc/library/mimetools.rst
@@ -0,0 +1,130 @@
+
+:mod:`mimetools` --- Tools for parsing MIME messages
+====================================================
+
+.. module:: mimetools
+ :synopsis: Tools for parsing MIME-style message bodies.
+
+
+.. deprecated:: 2.3
+ The :mod:`email` package should be used in preference to the :mod:`mimetools`
+ module. This module is present only to maintain backward compatibility.
+
+.. index:: module: rfc822
+
+This module defines a subclass of the :mod:`rfc822` module's :class:`Message`
+class and a number of utility functions that are useful for the manipulation for
+MIME multipart or encoded message.
+
+It defines the following items:
+
+
+.. class:: Message(fp[, seekable])
+
+ Return a new instance of the :class:`Message` class. This is a subclass of the
+ :class:`rfc822.Message` class, with some additional methods (see below). The
+ *seekable* argument has the same meaning as for :class:`rfc822.Message`.
+
+
+.. function:: choose_boundary()
+
+ Return a unique string that has a high likelihood of being usable as a part
+ boundary. The string has the form ``'hostipaddr.uid.pid.timestamp.random'``.
+
+
+.. function:: decode(input, output, encoding)
+
+ Read data encoded using the allowed MIME *encoding* from open file object
+ *input* and write the decoded data to open file object *output*. Valid values
+ for *encoding* include ``'base64'``, ``'quoted-printable'``, ``'uuencode'``,
+ ``'x-uuencode'``, ``'uue'``, ``'x-uue'``, ``'7bit'``, and ``'8bit'``. Decoding
+ messages encoded in ``'7bit'`` or ``'8bit'`` has no effect. The input is simply
+ copied to the output.
+
+
+.. function:: encode(input, output, encoding)
+
+ Read data from open file object *input* and write it encoded using the allowed
+ MIME *encoding* to open file object *output*. Valid values for *encoding* are
+ the same as for :meth:`decode`.
+
+
+.. function:: copyliteral(input, output)
+
+ Read lines from open file *input* until EOF and write them to open file
+ *output*.
+
+
+.. function:: copybinary(input, output)
+
+ Read blocks until EOF from open file *input* and write them to open file
+ *output*. The block size is currently fixed at 8192.
+
+
+.. seealso::
+
+ Module :mod:`email`
+ Comprehensive email handling package; supersedes the :mod:`mimetools` module.
+
+ Module :mod:`rfc822`
+ Provides the base class for :class:`mimetools.Message`.
+
+ Module :mod:`multifile`
+ Support for reading files which contain distinct parts, such as MIME data.
+
+ http://www.cs.uu.nl/wais/html/na-dir/mail/mime-faq/.html
+ The MIME Frequently Asked Questions document. For an overview of MIME, see the
+ answer to question 1.1 in Part 1 of this document.
+
+
+.. _mimetools-message-objects:
+
+Additional Methods of Message Objects
+-------------------------------------
+
+The :class:`Message` class defines the following methods in addition to the
+:class:`rfc822.Message` methods:
+
+
+.. method:: Message.getplist()
+
+ Return the parameter list of the :mailheader:`Content-Type` header. This is a
+ list of strings. For parameters of the form ``key=value``, *key* is converted
+ to lower case but *value* is not. For example, if the message contains the
+ header ``Content-type: text/html; spam=1; Spam=2; Spam`` then :meth:`getplist`
+ will return the Python list ``['spam=1', 'spam=2', 'Spam']``.
+
+
+.. method:: Message.getparam(name)
+
+ Return the *value* of the first parameter (as returned by :meth:`getplist`) of
+ the form ``name=value`` for the given *name*. If *value* is surrounded by
+ quotes of the form '``<``...\ ``>``' or '``"``...\ ``"``', these are removed.
+
+
+.. method:: Message.getencoding()
+
+ Return the encoding specified in the :mailheader:`Content-Transfer-Encoding`
+ message header. If no such header exists, return ``'7bit'``. The encoding is
+ converted to lower case.
+
+
+.. method:: Message.gettype()
+
+ Return the message type (of the form ``type/subtype``) as specified in the
+ :mailheader:`Content-Type` header. If no such header exists, return
+ ``'text/plain'``. The type is converted to lower case.
+
+
+.. method:: Message.getmaintype()
+
+ Return the main type as specified in the :mailheader:`Content-Type` header. If
+ no such header exists, return ``'text'``. The main type is converted to lower
+ case.
+
+
+.. method:: Message.getsubtype()
+
+ Return the subtype as specified in the :mailheader:`Content-Type` header. If no
+ such header exists, return ``'plain'``. The subtype is converted to lower case.
+
diff --git a/Doc/library/mimetypes.rst b/Doc/library/mimetypes.rst
new file mode 100644
index 0000000000..fd5e12d434
--- /dev/null
+++ b/Doc/library/mimetypes.rst
@@ -0,0 +1,232 @@
+
+:mod:`mimetypes` --- Map filenames to MIME types
+================================================
+
+.. module:: mimetypes
+ :synopsis: Mapping of filename extensions to MIME types.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. index:: pair: MIME; content type
+
+The :mod:`mimetypes` module converts between a filename or URL and the MIME type
+associated with the filename extension. Conversions are provided from filename
+to MIME type and from MIME type to filename extension; encodings are not
+supported for the latter conversion.
+
+The module provides one class and a number of convenience functions. The
+functions are the normal interface to this module, but some applications may be
+interested in the class as well.
+
+The functions described below provide the primary interface for this module. If
+the module has not been initialized, they will call :func:`init` if they rely on
+the information :func:`init` sets up.
+
+
+.. function:: guess_type(filename[, strict])
+
+ .. index:: pair: MIME; headers
+
+ Guess the type of a file based on its filename or URL, given by *filename*. The
+ return value is a tuple ``(type, encoding)`` where *type* is ``None`` if the
+ type can't be guessed (missing or unknown suffix) or a string of the form
+ ``'type/subtype'``, usable for a MIME :mailheader:`content-type` header.
+
+ *encoding* is ``None`` for no encoding or the name of the program used to encode
+ (e.g. :program:`compress` or :program:`gzip`). The encoding is suitable for use
+ as a :mailheader:`Content-Encoding` header, *not* as a
+ :mailheader:`Content-Transfer-Encoding` header. The mappings are table driven.
+ Encoding suffixes are case sensitive; type suffixes are first tried case
+ sensitively, then case insensitively.
+
+ Optional *strict* is a flag specifying whether the list of known MIME types
+ is limited to only the official types `registered with IANA
+ <http://www.isi.edu/in-notes/iana/assignments/media-types>`_ are recognized.
+ When *strict* is true (the default), only the IANA types are supported; when
+ *strict* is false, some additional non-standard but commonly used MIME types
+ are also recognized.
+
+
+.. function:: guess_all_extensions(type[, strict])
+
+ Guess the extensions for a file based on its MIME type, given by *type*. The
+ return value is a list of strings giving all possible filename extensions,
+ including the leading dot (``'.'``). The extensions are not guaranteed to have
+ been associated with any particular data stream, but would be mapped to the MIME
+ type *type* by :func:`guess_type`.
+
+ Optional *strict* has the same meaning as with the :func:`guess_type` function.
+
+
+.. function:: guess_extension(type[, strict])
+
+ Guess the extension for a file based on its MIME type, given by *type*. The
+ return value is a string giving a filename extension, including the leading dot
+ (``'.'``). The extension is not guaranteed to have been associated with any
+ particular data stream, but would be mapped to the MIME type *type* by
+ :func:`guess_type`. If no extension can be guessed for *type*, ``None`` is
+ returned.
+
+ Optional *strict* has the same meaning as with the :func:`guess_type` function.
+
+Some additional functions and data items are available for controlling the
+behavior of the module.
+
+
+.. function:: init([files])
+
+ Initialize the internal data structures. If given, *files* must be a sequence
+ of file names which should be used to augment the default type map. If omitted,
+ the file names to use are taken from :const:`knownfiles`. Each file named in
+ *files* or :const:`knownfiles` takes precedence over those named before it.
+ Calling :func:`init` repeatedly is allowed.
+
+
+.. function:: read_mime_types(filename)
+
+ Load the type map given in the file *filename*, if it exists. The type map is
+ returned as a dictionary mapping filename extensions, including the leading dot
+ (``'.'``), to strings of the form ``'type/subtype'``. If the file *filename*
+ does not exist or cannot be read, ``None`` is returned.
+
+
+.. function:: add_type(type, ext[, strict])
+
+ Add a mapping from the mimetype *type* to the extension *ext*. When the
+ extension is already known, the new type will replace the old one. When the type
+ is already known the extension will be added to the list of known extensions.
+
+ When *strict* is the mapping will added to the official MIME types, otherwise to
+ the non-standard ones.
+
+
+.. data:: inited
+
+ Flag indicating whether or not the global data structures have been initialized.
+ This is set to true by :func:`init`.
+
+
+.. data:: knownfiles
+
+ .. index:: single: file; mime.types
+
+ List of type map file names commonly installed. These files are typically named
+ :file:`mime.types` and are installed in different locations by different
+ packages.
+
+
+.. data:: suffix_map
+
+ Dictionary mapping suffixes to suffixes. This is used to allow recognition of
+ encoded files for which the encoding and the type are indicated by the same
+ extension. For example, the :file:`.tgz` extension is mapped to :file:`.tar.gz`
+ to allow the encoding and type to be recognized separately.
+
+
+.. data:: encodings_map
+
+ Dictionary mapping filename extensions to encoding types.
+
+
+.. data:: types_map
+
+ Dictionary mapping filename extensions to MIME types.
+
+
+.. data:: common_types
+
+ Dictionary mapping filename extensions to non-standard, but commonly found MIME
+ types.
+
+The :class:`MimeTypes` class may be useful for applications which may want more
+than one MIME-type database:
+
+
+.. class:: MimeTypes([filenames])
+
+ This class represents a MIME-types database. By default, it provides access to
+ the same database as the rest of this module. The initial database is a copy of
+ that provided by the module, and may be extended by loading additional
+ :file:`mime.types`\ -style files into the database using the :meth:`read` or
+ :meth:`readfp` methods. The mapping dictionaries may also be cleared before
+ loading additional data if the default data is not desired.
+
+ The optional *filenames* parameter can be used to cause additional files to be
+ loaded "on top" of the default database.
+
+ .. versionadded:: 2.2
+
+An example usage of the module::
+
+ >>> import mimetypes
+ >>> mimetypes.init()
+ >>> mimetypes.knownfiles
+ ['/etc/mime.types', '/etc/httpd/mime.types', ... ]
+ >>> mimetypes.suffix_map['.tgz']
+ '.tar.gz'
+ >>> mimetypes.encodings_map['.gz']
+ 'gzip'
+ >>> mimetypes.types_map['.tgz']
+ 'application/x-tar-gz'
+
+
+.. _mimetypes-objects:
+
+MimeTypes Objects
+-----------------
+
+:class:`MimeTypes` instances provide an interface which is very like that of the
+:mod:`mimetypes` module.
+
+
+.. attribute:: MimeTypes.suffix_map
+
+ Dictionary mapping suffixes to suffixes. This is used to allow recognition of
+ encoded files for which the encoding and the type are indicated by the same
+ extension. For example, the :file:`.tgz` extension is mapped to :file:`.tar.gz`
+ to allow the encoding and type to be recognized separately. This is initially a
+ copy of the global ``suffix_map`` defined in the module.
+
+
+.. attribute:: MimeTypes.encodings_map
+
+ Dictionary mapping filename extensions to encoding types. This is initially a
+ copy of the global ``encodings_map`` defined in the module.
+
+
+.. attribute:: MimeTypes.types_map
+
+ Dictionary mapping filename extensions to MIME types. This is initially a copy
+ of the global ``types_map`` defined in the module.
+
+
+.. attribute:: MimeTypes.common_types
+
+ Dictionary mapping filename extensions to non-standard, but commonly found MIME
+ types. This is initially a copy of the global ``common_types`` defined in the
+ module.
+
+
+.. method:: MimeTypes.guess_extension(type[, strict])
+
+ Similar to the :func:`guess_extension` function, using the tables stored as part
+ of the object.
+
+
+.. method:: MimeTypes.guess_type(url[, strict])
+
+ Similar to the :func:`guess_type` function, using the tables stored as part of
+ the object.
+
+
+.. method:: MimeTypes.read(path)
+
+ Load MIME information from a file named *path*. This uses :meth:`readfp` to
+ parse the file.
+
+
+.. method:: MimeTypes.readfp(file)
+
+ Load MIME type information from an open file. The file must have the format of
+ the standard :file:`mime.types` files.
+
diff --git a/Doc/library/miniaeframe.rst b/Doc/library/miniaeframe.rst
new file mode 100644
index 0000000000..5bf1b0724c
--- /dev/null
+++ b/Doc/library/miniaeframe.rst
@@ -0,0 +1,68 @@
+
+:mod:`MiniAEFrame` --- Open Scripting Architecture server support
+=================================================================
+
+.. module:: MiniAEFrame
+ :platform: Mac
+ :synopsis: Support to act as an Open Scripting Architecture (OSA) server ("Apple Events").
+
+
+.. index::
+ single: Open Scripting Architecture
+ single: AppleEvents
+ module: FrameWork
+
+The module :mod:`MiniAEFrame` provides a framework for an application that can
+function as an Open Scripting Architecture (OSA) server, i.e. receive and
+process AppleEvents. It can be used in conjunction with :mod:`FrameWork` or
+standalone. As an example, it is used in :program:`PythonCGISlave`.
+
+The :mod:`MiniAEFrame` module defines the following classes:
+
+
+.. class:: AEServer()
+
+ A class that handles AppleEvent dispatch. Your application should subclass this
+ class together with either :class:`MiniApplication` or
+ :class:`FrameWork.Application`. Your :meth:`__init__` method should call the
+ :meth:`__init__` method for both classes.
+
+
+.. class:: MiniApplication()
+
+ A class that is more or less compatible with :class:`FrameWork.Application` but
+ with less functionality. Its event loop supports the apple menu, command-dot and
+ AppleEvents; other events are passed on to the Python interpreter and/or Sioux.
+ Useful if your application wants to use :class:`AEServer` but does not provide
+ its own windows, etc.
+
+
+.. _aeserver-objects:
+
+AEServer Objects
+----------------
+
+
+.. method:: AEServer.installaehandler(classe, type, callback)
+
+ Installs an AppleEvent handler. *classe* and *type* are the four-character OSA
+ Class and Type designators, ``'****'`` wildcards are allowed. When a matching
+ AppleEvent is received the parameters are decoded and your callback is invoked.
+
+
+.. method:: AEServer.callback(_object, **kwargs)
+
+ Your callback is called with the OSA Direct Object as first positional
+ parameter. The other parameters are passed as keyword arguments, with the
+ 4-character designator as name. Three extra keyword parameters are passed:
+ ``_class`` and ``_type`` are the Class and Type designators and ``_attributes``
+ is a dictionary with the AppleEvent attributes.
+
+ The return value of your method is packed with :func:`aetools.packevent` and
+ sent as reply.
+
+Note that there are some serious problems with the current design. AppleEvents
+which have non-identifier 4-character designators for arguments are not
+implementable, and it is not possible to return an error to the originator. This
+will be addressed in a future release.
+
diff --git a/Doc/library/misc.rst b/Doc/library/misc.rst
new file mode 100644
index 0000000000..ee22561079
--- /dev/null
+++ b/Doc/library/misc.rst
@@ -0,0 +1,14 @@
+
+.. _misc:
+
+**********************
+Miscellaneous Services
+**********************
+
+The modules described in this chapter provide miscellaneous services that are
+available in all Python versions. Here's an overview:
+
+
+.. toctree::
+
+ formatter.rst
diff --git a/Doc/library/mm.rst b/Doc/library/mm.rst
new file mode 100644
index 0000000000..a7fbbecb3c
--- /dev/null
+++ b/Doc/library/mm.rst
@@ -0,0 +1,23 @@
+
+.. _mmedia:
+
+*******************
+Multimedia Services
+*******************
+
+The modules described in this chapter implement various algorithms or interfaces
+that are mainly useful for multimedia applications. They are available at the
+discretion of the installation. Here's an overview:
+
+
+.. toctree::
+
+ audioop.rst
+ aifc.rst
+ sunau.rst
+ wave.rst
+ chunk.rst
+ colorsys.rst
+ imghdr.rst
+ sndhdr.rst
+ ossaudiodev.rst
diff --git a/Doc/library/mmap.rst b/Doc/library/mmap.rst
new file mode 100644
index 0000000000..abe5b7bd07
--- /dev/null
+++ b/Doc/library/mmap.rst
@@ -0,0 +1,173 @@
+
+:mod:`mmap` --- Memory-mapped file support
+==========================================
+
+.. module:: mmap
+ :synopsis: Interface to memory-mapped files for Unix and Windows.
+
+
+Memory-mapped file objects behave like both strings and like file objects.
+Unlike normal string objects, however, these are mutable. You can use mmap
+objects in most places where strings are expected; for example, you can use the
+:mod:`re` module to search through a memory-mapped file. Since they're mutable,
+you can change a single character by doing ``obj[index] = 'a'``, or change a
+substring by assigning to a slice: ``obj[i1:i2] = '...'``. You can also read
+and write data starting at the current file position, and :meth:`seek` through
+the file to different positions.
+
+A memory-mapped file is created by the :func:`mmap` function, which is different
+on Unix and on Windows. In either case you must provide a file descriptor for a
+file opened for update. If you wish to map an existing Python file object, use
+its :meth:`fileno` method to obtain the correct value for the *fileno*
+parameter. Otherwise, you can open the file using the :func:`os.open` function,
+which returns a file descriptor directly (the file still needs to be closed when
+done).
+
+For both the Unix and Windows versions of the function, *access* may be
+specified as an optional keyword parameter. *access* accepts one of three
+values: :const:`ACCESS_READ`, :const:`ACCESS_WRITE`, or :const:`ACCESS_COPY` to
+specify readonly, write-through or copy-on-write memory respectively. *access*
+can be used on both Unix and Windows. If *access* is not specified, Windows
+mmap returns a write-through mapping. The initial memory values for all three
+access types are taken from the specified file. Assignment to an
+:const:`ACCESS_READ` memory map raises a :exc:`TypeError` exception. Assignment
+to an :const:`ACCESS_WRITE` memory map affects both memory and the underlying
+file. Assignment to an :const:`ACCESS_COPY` memory map affects memory but does
+not update the underlying file.
+
+.. versionchanged:: 2.5
+ To map anonymous memory, -1 should be passed as the fileno along with the
+ length.
+
+
+.. function:: mmap(fileno, length[, tagname[, access]])
+
+ **(Windows version)** Maps *length* bytes from the file specified by the file
+ handle *fileno*, and returns a mmap object. If *length* is larger than the
+ current size of the file, the file is extended to contain *length* bytes. If
+ *length* is ``0``, the maximum length of the map is the current size of the
+ file, except that if the file is empty Windows raises an exception (you cannot
+ create an empty mapping on Windows).
+
+ *tagname*, if specified and not ``None``, is a string giving a tag name for the
+ mapping. Windows allows you to have many different mappings against the same
+ file. If you specify the name of an existing tag, that tag is opened, otherwise
+ a new tag of this name is created. If this parameter is omitted or ``None``,
+ the mapping is created without a name. Avoiding the use of the tag parameter
+ will assist in keeping your code portable between Unix and Windows.
+
+
+.. function:: mmap(fileno, length[, flags[, prot[, access]]])
+ :noindex:
+
+ **(Unix version)** Maps *length* bytes from the file specified by the file
+ descriptor *fileno*, and returns a mmap object. If *length* is ``0``, the
+ maximum length of the map will be the current size of the file when :func:`mmap`
+ is called.
+
+ *flags* specifies the nature of the mapping. :const:`MAP_PRIVATE` creates a
+ private copy-on-write mapping, so changes to the contents of the mmap object
+ will be private to this process, and :const:`MAP_SHARED` creates a mapping
+ that's shared with all other processes mapping the same areas of the file. The
+ default value is :const:`MAP_SHARED`.
+
+ *prot*, if specified, gives the desired memory protection; the two most useful
+ values are :const:`PROT_READ` and :const:`PROT_WRITE`, to specify that the pages
+ may be read or written. *prot* defaults to :const:`PROT_READ \| PROT_WRITE`.
+
+ *access* may be specified in lieu of *flags* and *prot* as an optional keyword
+ parameter. It is an error to specify both *flags*, *prot* and *access*. See
+ the description of *access* above for information on how to use this parameter.
+
+Memory-mapped file objects support the following methods:
+
+
+.. method:: mmap.close()
+
+ Close the file. Subsequent calls to other methods of the object will result in
+ an exception being raised.
+
+
+.. method:: mmap.find(string[, start])
+
+ Returns the lowest index in the object where the substring *string* is found.
+ Returns ``-1`` on failure. *start* is the index at which the search begins, and
+ defaults to zero.
+
+
+.. method:: mmap.flush([offset, size])
+
+ Flushes changes made to the in-memory copy of a file back to disk. Without use
+ of this call there is no guarantee that changes are written back before the
+ object is destroyed. If *offset* and *size* are specified, only changes to the
+ given range of bytes will be flushed to disk; otherwise, the whole extent of the
+ mapping is flushed.
+
+
+.. method:: mmap.move(dest, src, count)
+
+ Copy the *count* bytes starting at offset *src* to the destination index *dest*.
+ If the mmap was created with :const:`ACCESS_READ`, then calls to move will throw
+ a :exc:`TypeError` exception.
+
+
+.. method:: mmap.read(num)
+
+ Return a string containing up to *num* bytes starting from the current file
+ position; the file position is updated to point after the bytes that were
+ returned.
+
+
+.. method:: mmap.read_byte()
+
+ Returns a string of length 1 containing the character at the current file
+ position, and advances the file position by 1.
+
+
+.. method:: mmap.readline()
+
+ Returns a single line, starting at the current file position and up to the next
+ newline.
+
+
+.. method:: mmap.resize(newsize)
+
+ Resizes the map and the underlying file, if any. If the mmap was created with
+ :const:`ACCESS_READ` or :const:`ACCESS_COPY`, resizing the map will throw a
+ :exc:`TypeError` exception.
+
+
+.. method:: mmap.seek(pos[, whence])
+
+ Set the file's current position. *whence* argument is optional and defaults to
+ ``os.SEEK_SET`` or ``0`` (absolute file positioning); other values are
+ ``os.SEEK_CUR`` or ``1`` (seek relative to the current position) and
+ ``os.SEEK_END`` or ``2`` (seek relative to the file's end).
+
+
+.. method:: mmap.size()
+
+ Return the length of the file, which can be larger than the size of the
+ memory-mapped area.
+
+
+.. method:: mmap.tell()
+
+ Returns the current position of the file pointer.
+
+
+.. method:: mmap.write(string)
+
+ Write the bytes in *string* into memory at the current position of the file
+ pointer; the file position is updated to point after the bytes that were
+ written. If the mmap was created with :const:`ACCESS_READ`, then writing to it
+ will throw a :exc:`TypeError` exception.
+
+
+.. method:: mmap.write_byte(byte)
+
+ Write the single-character string *byte* into memory at the current position of
+ the file pointer; the file position is advanced by ``1``. If the mmap was
+ created with :const:`ACCESS_READ`, then writing to it will throw a
+ :exc:`TypeError` exception.
+
diff --git a/Doc/library/modulefinder.rst b/Doc/library/modulefinder.rst
new file mode 100644
index 0000000000..334bd5d0bd
--- /dev/null
+++ b/Doc/library/modulefinder.rst
@@ -0,0 +1,52 @@
+
+:mod:`modulefinder` --- Find modules used by a script
+=====================================================
+
+.. sectionauthor:: A.M. Kuchling <amk@amk.ca>
+
+
+.. module:: modulefinder
+ :synopsis: Find modules used by a script.
+
+
+.. versionadded:: 2.3
+
+This module provides a :class:`ModuleFinder` class that can be used to determine
+the set of modules imported by a script. ``modulefinder.py`` can also be run as
+a script, giving the filename of a Python script as its argument, after which a
+report of the imported modules will be printed.
+
+
+.. function:: AddPackagePath(pkg_name, path)
+
+ Record that the package named *pkg_name* can be found in the specified *path*.
+
+
+.. function:: ReplacePackage(oldname, newname)
+
+ Allows specifying that the module named *oldname* is in fact the package named
+ *newname*. The most common usage would be to handle how the :mod:`_xmlplus`
+ package replaces the :mod:`xml` package.
+
+
+.. class:: ModuleFinder([path=None, debug=0, excludes=[], replace_paths=[]])
+
+ This class provides :meth:`run_script` and :meth:`report` methods to determine
+ the set of modules imported by a script. *path* can be a list of directories to
+ search for modules; if not specified, ``sys.path`` is used. *debug* sets the
+ debugging level; higher values make the class print debugging messages about
+ what it's doing. *excludes* is a list of module names to exclude from the
+ analysis. *replace_paths* is a list of ``(oldpath, newpath)`` tuples that will
+ be replaced in module paths.
+
+
+.. method:: ModuleFinder.report()
+
+ Print a report to standard output that lists the modules imported by the script
+ and their paths, as well as modules that are missing or seem to be missing.
+
+
+.. method:: ModuleFinder.run_script(pathname)
+
+ Analyze the contents of the *pathname* file, which must contain Python code.
+
diff --git a/Doc/library/modules.rst b/Doc/library/modules.rst
new file mode 100644
index 0000000000..2590a3a678
--- /dev/null
+++ b/Doc/library/modules.rst
@@ -0,0 +1,20 @@
+
+.. _modules:
+
+*****************
+Importing Modules
+*****************
+
+The modules described in this chapter provide new ways to import other Python
+modules and hooks for customizing the import process.
+
+The full list of modules described in this chapter is:
+
+
+.. toctree::
+
+ imp.rst
+ zipimport.rst
+ pkgutil.rst
+ modulefinder.rst
+ runpy.rst
diff --git a/Doc/library/msilib.rst b/Doc/library/msilib.rst
new file mode 100644
index 0000000000..6c7955a7fe
--- /dev/null
+++ b/Doc/library/msilib.rst
@@ -0,0 +1,537 @@
+
+:mod:`msilib` --- Read and write Microsoft Installer files
+==========================================================
+
+.. module:: msilib
+ :platform: Windows
+ :synopsis: Creation of Microsoft Installer files, and CAB files.
+.. moduleauthor:: Martin v. Löwis <martin@v.loewis.de>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. index:: single: msi
+
+.. versionadded:: 2.5
+
+The :mod:`msilib` supports the creation of Microsoft Installer (``.msi``) files.
+Because these files often contain an embedded "cabinet" file (``.cab``), it also
+exposes an API to create CAB files. Support for reading ``.cab`` files is
+currently not implemented; read support for the ``.msi`` database is possible.
+
+This package aims to provide complete access to all tables in an ``.msi`` file,
+therefore, it is a fairly low-level API. Two primary applications of this
+package are the :mod:`distutils` command ``bdist_msi``, and the creation of
+Python installer package itself (although that currently uses a different
+version of ``msilib``).
+
+The package contents can be roughly split into four parts: low-level CAB
+routines, low-level MSI routines, higher-level MSI routines, and standard table
+structures.
+
+
+.. function:: FCICreate(cabname, files)
+
+ Create a new CAB file named *cabname*. *files* must be a list of tuples, each
+ containing the name of the file on disk, and the name of the file inside the CAB
+ file.
+
+ The files are added to the CAB file in the order they appear in the list. All
+ files are added into a single CAB file, using the MSZIP compression algorithm.
+
+ Callbacks to Python for the various steps of MSI creation are currently not
+ exposed.
+
+
+.. function:: UUIDCreate()
+
+ Return the string representation of a new unique identifier. This wraps the
+ Windows API functions :cfunc:`UuidCreate` and :cfunc:`UuidToString`.
+
+
+.. function:: OpenDatabase(path, persist)
+
+ Return a new database object by calling MsiOpenDatabase. *path* is the file
+ name of the MSI file; *persist* can be one of the constants
+ ``MSIDBOPEN_CREATEDIRECT``, ``MSIDBOPEN_CREATE``, ``MSIDBOPEN_DIRECT``,
+ ``MSIDBOPEN_READONLY``, or ``MSIDBOPEN_TRANSACT``, and may include the flag
+ ``MSIDBOPEN_PATCHFILE``. See the Microsoft documentation for the meaning of
+ these flags; depending on the flags, an existing database is opened, or a new
+ one created.
+
+
+.. function:: CreateRecord(count)
+
+ Return a new record object by calling :cfunc:`MSICreateRecord`. *count* is the
+ number of fields of the record.
+
+
+.. function:: init_database(name, schema, ProductName, ProductCode, ProductVersion, Manufacturer)
+
+ Create and return a new database *name*, initialize it with *schema*, and set
+ the properties *ProductName*, *ProductCode*, *ProductVersion*, and
+ *Manufacturer*.
+
+ *schema* must be a module object containing ``tables`` and
+ ``_Validation_records`` attributes; typically, :mod:`msilib.schema` should be
+ used.
+
+ The database will contain just the schema and the validation records when this
+ function returns.
+
+
+.. function:: add_data(database, records)
+
+ Add all *records* to *database*. *records* should be a list of tuples, each one
+ containing all fields of a record according to the schema of the table. For
+ optional fields, ``None`` can be passed.
+
+ Field values can be int or long numbers, strings, or instances of the Binary
+ class.
+
+
+.. class:: Binary(filename)
+
+ Represents entries in the Binary table; inserting such an object using
+ :func:`add_data` reads the file named *filename* into the table.
+
+
+.. function:: add_tables(database, module)
+
+ Add all table content from *module* to *database*. *module* must contain an
+ attribute *tables* listing all tables for which content should be added, and one
+ attribute per table that has the actual content.
+
+ This is typically used to install the sequence tables.
+
+
+.. function:: add_stream(database, name, path)
+
+ Add the file *path* into the ``_Stream`` table of *database*, with the stream
+ name *name*.
+
+
+.. function:: gen_uuid()
+
+ Return a new UUID, in the format that MSI typically requires (i.e. in curly
+ braces, and with all hexdigits in upper-case).
+
+
+.. seealso::
+
+ `FCICreateFile <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/devnotes/winprog/fcicreate.asp>`_
+ `UuidCreate <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/rpc/rpc/uuidcreate.asp>`_
+ `UuidToString <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/rpc/rpc/uuidtostring.asp>`_
+
+.. _database-objects:
+
+Database Objects
+----------------
+
+
+.. method:: Database.OpenView(sql)
+
+ Return a view object, by calling :cfunc:`MSIDatabaseOpenView`. *sql* is the SQL
+ statement to execute.
+
+
+.. method:: Database.Commit()
+
+ Commit the changes pending in the current transaction, by calling
+ :cfunc:`MSIDatabaseCommit`.
+
+
+.. method:: Database.GetSummaryInformation(count)
+
+ Return a new summary information object, by calling
+ :cfunc:`MsiGetSummaryInformation`. *count* is the maximum number of updated
+ values.
+
+
+.. seealso::
+
+ `MSIOpenView <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msiopenview.asp>`_
+ `MSIDatabaseCommit <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msidatabasecommit.asp>`_
+ `MSIGetSummaryInformation <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msigetsummaryinformation.asp>`_
+
+.. _view-objects:
+
+View Objects
+------------
+
+
+.. method:: View.Execute([params=None])
+
+ Execute the SQL query of the view, through :cfunc:`MSIViewExecute`. *params* is
+ an optional record describing actual values of the parameter tokens in the
+ query.
+
+
+.. method:: View.GetColumnInfo(kind)
+
+ Return a record describing the columns of the view, through calling
+ :cfunc:`MsiViewGetColumnInfo`. *kind* can be either ``MSICOLINFO_NAMES`` or
+ ``MSICOLINFO_TYPES``.
+
+
+.. method:: View.Fetch()
+
+ Return a result record of the query, through calling :cfunc:`MsiViewFetch`.
+
+
+.. method:: View.Modify(kind, data)
+
+ Modify the view, by calling :cfunc:`MsiViewModify`. *kind* can be one of
+ ``MSIMODIFY_SEEK``, ``MSIMODIFY_REFRESH``, ``MSIMODIFY_INSERT``,
+ ``MSIMODIFY_UPDATE``, ``MSIMODIFY_ASSIGN``, ``MSIMODIFY_REPLACE``,
+ ``MSIMODIFY_MERGE``, ``MSIMODIFY_DELETE``, ``MSIMODIFY_INSERT_TEMPORARY``,
+ ``MSIMODIFY_VALIDATE``, ``MSIMODIFY_VALIDATE_NEW``,
+ ``MSIMODIFY_VALIDATE_FIELD``, or ``MSIMODIFY_VALIDATE_DELETE``.
+
+ *data* must be a record describing the new data.
+
+
+.. method:: View.Close()
+
+ Close the view, through :cfunc:`MsiViewClose`.
+
+
+.. seealso::
+
+ `MsiViewExecute <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msiviewexecute.asp>`_
+ `MSIViewGetColumnInfo <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msiviewgetcolumninfo.asp>`_
+ `MsiViewFetch <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msiviewfetch.asp>`_
+ `MsiViewModify <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msiviewmodify.asp>`_
+ `MsiViewClose <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msiviewclose.asp>`_
+
+.. _summary-objects:
+
+Summary Information Objects
+---------------------------
+
+
+.. method:: SummaryInformation.GetProperty(field)
+
+ Return a property of the summary, through :cfunc:`MsiSummaryInfoGetProperty`.
+ *field* is the name of the property, and can be one of the constants
+ ``PID_CODEPAGE``, ``PID_TITLE``, ``PID_SUBJECT``, ``PID_AUTHOR``,
+ ``PID_KEYWORDS``, ``PID_COMMENTS``, ``PID_TEMPLATE``, ``PID_LASTAUTHOR``,
+ ``PID_REVNUMBER``, ``PID_LASTPRINTED``, ``PID_CREATE_DTM``,
+ ``PID_LASTSAVE_DTM``, ``PID_PAGECOUNT``, ``PID_WORDCOUNT``, ``PID_CHARCOUNT``,
+ ``PID_APPNAME``, or ``PID_SECURITY``.
+
+
+.. method:: SummaryInformation.GetPropertyCount()
+
+ Return the number of summary properties, through
+ :cfunc:`MsiSummaryInfoGetPropertyCount`.
+
+
+.. method:: SummaryInformation.SetProperty(field, value)
+
+ Set a property through :cfunc:`MsiSummaryInfoSetProperty`. *field* can have the
+ same values as in :meth:`GetProperty`, *value* is the new value of the property.
+ Possible value types are integer and string.
+
+
+.. method:: SummaryInformation.Persist()
+
+ Write the modified properties to the summary information stream, using
+ :cfunc:`MsiSummaryInfoPersist`.
+
+
+.. seealso::
+
+ `MsiSummaryInfoGetProperty <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msisummaryinfogetproperty.asp>`_
+ `MsiSummaryInfoGetPropertyCount <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msisummaryinfogetpropertycount.asp>`_
+ `MsiSummaryInfoSetProperty <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msisummaryinfosetproperty.asp>`_
+ `MsiSummaryInfoPersist <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msisummaryinfopersist.asp>`_
+
+.. _record-objects:
+
+Record Objects
+--------------
+
+
+.. method:: Record.GetFieldCount()
+
+ Return the number of fields of the record, through
+ :cfunc:`MsiRecordGetFieldCount`.
+
+
+.. method:: Record.SetString(field, value)
+
+ Set *field* to *value* through :cfunc:`MsiRecordSetString`. *field* must be an
+ integer; *value* a string.
+
+
+.. method:: Record.SetStream(field, value)
+
+ Set *field* to the contents of the file named *value*, through
+ :cfunc:`MsiRecordSetStream`. *field* must be an integer; *value* a string.
+
+
+.. method:: Record.SetInteger(field, value)
+
+ Set *field* to *value* through :cfunc:`MsiRecordSetInteger`. Both *field* and
+ *value* must be an integer.
+
+
+.. method:: Record.ClearData()
+
+ Set all fields of the record to 0, through :cfunc:`MsiRecordClearData`.
+
+
+.. seealso::
+
+ `MsiRecordGetFieldCount <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msirecordgetfieldcount.asp>`_
+ `MsiRecordSetString <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msirecordsetstring.asp>`_
+ `MsiRecordSetStream <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msirecordsetstream.asp>`_
+ `MsiRecordSetInteger <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msirecordsetinteger.asp>`_
+ `MsiRecordClear <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msirecordclear.asp>`_
+
+.. _msi-errors:
+
+Errors
+------
+
+All wrappers around MSI functions raise :exc:`MsiError`; the string inside the
+exception will contain more detail.
+
+
+.. _cab:
+
+CAB Objects
+-----------
+
+
+.. class:: CAB(name)
+
+ The class :class:`CAB` represents a CAB file. During MSI construction, files
+ will be added simultaneously to the ``Files`` table, and to a CAB file. Then,
+ when all files have been added, the CAB file can be written, then added to the
+ MSI file.
+
+ *name* is the name of the CAB file in the MSI file.
+
+
+.. method:: CAB.append(full, file, logical)
+
+ Add the file with the pathname *full* to the CAB file, under the name *logical*.
+ If there is already a file named *logical*, a new file name is created.
+
+ Return the index of the file in the CAB file, and the new name of the file
+ inside the CAB file.
+
+
+.. method:: CAB.commit(database)
+
+ Generate a CAB file, add it as a stream to the MSI file, put it into the
+ ``Media`` table, and remove the generated file from the disk.
+
+
+.. _msi-directory:
+
+Directory Objects
+-----------------
+
+
+.. class:: Directory(database, cab, basedir, physical, logical, default, component, [componentflags])
+
+ Create a new directory in the Directory table. There is a current component at
+ each point in time for the directory, which is either explicitly created through
+ :meth:`start_component`, or implicitly when files are added for the first time.
+ Files are added into the current component, and into the cab file. To create a
+ directory, a base directory object needs to be specified (can be ``None``), the
+ path to the physical directory, and a logical directory name. *default*
+ specifies the DefaultDir slot in the directory table. *componentflags* specifies
+ the default flags that new components get.
+
+
+.. method:: Directory.start_component([component[, feature[, flags[, keyfile[, uuid]]]]])
+
+ Add an entry to the Component table, and make this component the current
+ component for this directory. If no component name is given, the directory name
+ is used. If no *feature* is given, the current feature is used. If no *flags*
+ are given, the directory's default flags are used. If no *keyfile* is given, the
+ KeyPath is left null in the Component table.
+
+
+.. method:: Directory.add_file(file[, src[, version[, language]]])
+
+ Add a file to the current component of the directory, starting a new one if
+ there is no current component. By default, the file name in the source and the
+ file table will be identical. If the *src* file is specified, it is interpreted
+ relative to the current directory. Optionally, a *version* and a *language* can
+ be specified for the entry in the File table.
+
+
+.. method:: Directory.glob(pattern[, exclude])
+
+ Add a list of files to the current component as specified in the glob pattern.
+ Individual files can be excluded in the *exclude* list.
+
+
+.. method:: Directory.remove_pyc()
+
+ Remove ``.pyc``/``.pyo`` files on uninstall.
+
+
+.. seealso::
+
+ `Directory Table <http://msdn.microsoft.com/library/en-us/msi/setup/directory_table.asp>`_
+ `File Table <http://msdn.microsoft.com/library/en-us/msi/setup/file_table.asp>`_
+ `Component Table <http://msdn.microsoft.com/library/en-us/msi/setup/component_table.asp>`_
+ `FeatureComponents Table <http://msdn.microsoft.com/library/en-us/msi/setup/featurecomponents_table.asp>`_
+
+.. _features:
+
+Features
+--------
+
+
+.. class:: Feature(database, id, title, desc, display[, level=1[, parent[, directory[, attributes=0]]]])
+
+ Add a new record to the ``Feature`` table, using the values *id*, *parent.id*,
+ *title*, *desc*, *display*, *level*, *directory*, and *attributes*. The
+ resulting feature object can be passed to the :meth:`start_component` method of
+ :class:`Directory`.
+
+
+.. method:: Feature.set_current()
+
+ Make this feature the current feature of :mod:`msilib`. New components are
+ automatically added to the default feature, unless a feature is explicitly
+ specified.
+
+
+.. seealso::
+
+ `Feature Table <http://msdn.microsoft.com/library/en-us/msi/setup/feature_table.asp>`_
+
+.. _msi-gui:
+
+GUI classes
+-----------
+
+:mod:`msilib` provides several classes that wrap the GUI tables in an MSI
+database. However, no standard user interface is provided; use :mod:`bdist_msi`
+to create MSI files with a user-interface for installing Python packages.
+
+
+.. class:: Control(dlg, name)
+
+ Base class of the dialog controls. *dlg* is the dialog object the control
+ belongs to, and *name* is the control's name.
+
+
+.. method:: Control.event(event, argument[, condition=1[, ordering]])
+
+ Make an entry into the ``ControlEvent`` table for this control.
+
+
+.. method:: Control.mapping(event, attribute)
+
+ Make an entry into the ``EventMapping`` table for this control.
+
+
+.. method:: Control.condition(action, condition)
+
+ Make an entry into the ``ControlCondition`` table for this control.
+
+
+.. class:: RadioButtonGroup(dlg, name, property)
+
+ Create a radio button control named *name*. *property* is the installer property
+ that gets set when a radio button is selected.
+
+
+.. method:: RadioButtonGroup.add(name, x, y, width, height, text [, value])
+
+ Add a radio button named *name* to the group, at the coordinates *x*, *y*,
+ *width*, *height*, and with the label *text*. If *value* is omitted, it defaults
+ to *name*.
+
+
+.. class:: Dialog(db, name, x, y, w, h, attr, title, first, default, cancel)
+
+ Return a new :class:`Dialog` object. An entry in the ``Dialog`` table is made,
+ with the specified coordinates, dialog attributes, title, name of the first,
+ default, and cancel controls.
+
+
+.. method:: Dialog.control(name, type, x, y, width, height, attributes, property, text, control_next, help)
+
+ Return a new :class:`Control` object. An entry in the ``Control`` table is made
+ with the specified parameters.
+
+ This is a generic method; for specific types, specialized methods are provided.
+
+
+.. method:: Dialog.text(name, x, y, width, height, attributes, text)
+
+ Add and return a ``Text`` control.
+
+
+.. method:: Dialog.bitmap(name, x, y, width, height, text)
+
+ Add and return a ``Bitmap`` control.
+
+
+.. method:: Dialog.line(name, x, y, width, height)
+
+ Add and return a ``Line`` control.
+
+
+.. method:: Dialog.pushbutton(name, x, y, width, height, attributes, text, next_control)
+
+ Add and return a ``PushButton`` control.
+
+
+.. method:: Dialog.radiogroup(name, x, y, width, height, attributes, property, text, next_control)
+
+ Add and return a ``RadioButtonGroup`` control.
+
+
+.. method:: Dialog.checkbox(name, x, y, width, height, attributes, property, text, next_control)
+
+ Add and return a ``CheckBox`` control.
+
+
+.. seealso::
+
+ `Dialog Table <http://msdn.microsoft.com/library/en-us/msi/setup/dialog_table.asp>`_
+ `Control Table <http://msdn.microsoft.com/library/en-us/msi/setup/control_table.asp>`_
+ `Control Types <http://msdn.microsoft.com/library/en-us/msi/setup/controls.asp>`_
+ `ControlCondition Table <http://msdn.microsoft.com/library/en-us/msi/setup/controlcondition_table.asp>`_
+ `ControlEvent Table <http://msdn.microsoft.com/library/en-us/msi/setup/controlevent_table.asp>`_
+ `EventMapping Table <http://msdn.microsoft.com/library/en-us/msi/setup/eventmapping_table.asp>`_
+ `RadioButton Table <http://msdn.microsoft.com/library/en-us/msi/setup/radiobutton_table.asp>`_
+
+.. _msi-tables:
+
+Precomputed tables
+------------------
+
+:mod:`msilib` provides a few subpackages that contain only schema and table
+definitions. Currently, these definitions are based on MSI version 2.0.
+
+
+.. data:: schema
+
+ This is the standard MSI schema for MSI 2.0, with the *tables* variable
+ providing a list of table definitions, and *_Validation_records* providing the
+ data for MSI validation.
+
+
+.. data:: sequence
+
+ This module contains table contents for the standard sequence tables:
+ *AdminExecuteSequence*, *AdminUISequence*, *AdvtExecuteSequence*,
+ *InstallExecuteSequence*, and *InstallUISequence*.
+
+
+.. data:: text
+
+ This module contains definitions for the UIText and ActionText tables, for the
+ standard installer actions.
+
diff --git a/Doc/library/msvcrt.rst b/Doc/library/msvcrt.rst
new file mode 100644
index 0000000000..d43bb4c60f
--- /dev/null
+++ b/Doc/library/msvcrt.rst
@@ -0,0 +1,126 @@
+
+:mod:`msvcrt` -- Useful routines from the MS VC++ runtime
+=========================================================
+
+.. module:: msvcrt
+ :platform: Windows
+ :synopsis: Miscellaneous useful routines from the MS VC++ runtime.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+These functions provide access to some useful capabilities on Windows platforms.
+Some higher-level modules use these functions to build the Windows
+implementations of their services. For example, the :mod:`getpass` module uses
+this in the implementation of the :func:`getpass` function.
+
+Further documentation on these functions can be found in the Platform API
+documentation.
+
+
+.. _msvcrt-files:
+
+File Operations
+---------------
+
+
+.. function:: locking(fd, mode, nbytes)
+
+ Lock part of a file based on file descriptor *fd* from the C runtime. Raises
+ :exc:`IOError` on failure. The locked region of the file extends from the
+ current file position for *nbytes* bytes, and may continue beyond the end of the
+ file. *mode* must be one of the :const:`LK_\*` constants listed below. Multiple
+ regions in a file may be locked at the same time, but may not overlap. Adjacent
+ regions are not merged; they must be unlocked individually.
+
+
+.. data:: LK_LOCK
+ LK_RLCK
+
+ Locks the specified bytes. If the bytes cannot be locked, the program
+ immediately tries again after 1 second. If, after 10 attempts, the bytes cannot
+ be locked, :exc:`IOError` is raised.
+
+
+.. data:: LK_NBLCK
+ LK_NBRLCK
+
+ Locks the specified bytes. If the bytes cannot be locked, :exc:`IOError` is
+ raised.
+
+
+.. data:: LK_UNLCK
+
+ Unlocks the specified bytes, which must have been previously locked.
+
+
+.. function:: setmode(fd, flags)
+
+ Set the line-end translation mode for the file descriptor *fd*. To set it to
+ text mode, *flags* should be :const:`os.O_TEXT`; for binary, it should be
+ :const:`os.O_BINARY`.
+
+
+.. function:: open_osfhandle(handle, flags)
+
+ Create a C runtime file descriptor from the file handle *handle*. The *flags*
+ parameter should be a bit-wise OR of :const:`os.O_APPEND`, :const:`os.O_RDONLY`,
+ and :const:`os.O_TEXT`. The returned file descriptor may be used as a parameter
+ to :func:`os.fdopen` to create a file object.
+
+
+.. function:: get_osfhandle(fd)
+
+ Return the file handle for the file descriptor *fd*. Raises :exc:`IOError` if
+ *fd* is not recognized.
+
+
+.. _msvcrt-console:
+
+Console I/O
+-----------
+
+
+.. function:: kbhit()
+
+ Return true if a keypress is waiting to be read.
+
+
+.. function:: getch()
+
+ Read a keypress and return the resulting character. Nothing is echoed to the
+ console. This call will block if a keypress is not already available, but will
+ not wait for :kbd:`Enter` to be pressed. If the pressed key was a special
+ function key, this will return ``'\000'`` or ``'\xe0'``; the next call will
+ return the keycode. The :kbd:`Control-C` keypress cannot be read with this
+ function.
+
+
+.. function:: getche()
+
+ Similar to :func:`getch`, but the keypress will be echoed if it represents a
+ printable character.
+
+
+.. function:: putch(char)
+
+ Print the character *char* to the console without buffering.
+
+
+.. function:: ungetch(char)
+
+ Cause the character *char* to be "pushed back" into the console buffer; it will
+ be the next character read by :func:`getch` or :func:`getche`.
+
+
+.. _msvcrt-other:
+
+Other Functions
+---------------
+
+
+.. function:: heapmin()
+
+ Force the :cfunc:`malloc` heap to clean itself up and return unused blocks to
+ the operating system. This only works on Windows NT. On failure, this raises
+ :exc:`IOError`.
+
diff --git a/Doc/library/multifile.rst b/Doc/library/multifile.rst
new file mode 100644
index 0000000000..c36ccb7a0f
--- /dev/null
+++ b/Doc/library/multifile.rst
@@ -0,0 +1,190 @@
+
+:mod:`multifile` --- Support for files containing distinct parts
+================================================================
+
+.. module:: multifile
+ :synopsis: Support for reading files which contain distinct parts, such as some MIME data.
+.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+
+
+.. deprecated:: 2.5
+ The :mod:`email` package should be used in preference to the :mod:`multifile`
+ module. This module is present only to maintain backward compatibility.
+
+The :class:`MultiFile` object enables you to treat sections of a text file as
+file-like input objects, with ``''`` being returned by :meth:`readline` when a
+given delimiter pattern is encountered. The defaults of this class are designed
+to make it useful for parsing MIME multipart messages, but by subclassing it and
+overriding methods it can be easily adapted for more general use.
+
+
+.. class:: MultiFile(fp[, seekable])
+
+ Create a multi-file. You must instantiate this class with an input object
+ argument for the :class:`MultiFile` instance to get lines from, such as a file
+ object returned by :func:`open`.
+
+ :class:`MultiFile` only ever looks at the input object's :meth:`readline`,
+ :meth:`seek` and :meth:`tell` methods, and the latter two are only needed if you
+ want random access to the individual MIME parts. To use :class:`MultiFile` on a
+ non-seekable stream object, set the optional *seekable* argument to false; this
+ will prevent using the input object's :meth:`seek` and :meth:`tell` methods.
+
+It will be useful to know that in :class:`MultiFile`'s view of the world, text
+is composed of three kinds of lines: data, section-dividers, and end-markers.
+MultiFile is designed to support parsing of messages that may have multiple
+nested message parts, each with its own pattern for section-divider and
+end-marker lines.
+
+
+.. seealso::
+
+ Module :mod:`email`
+ Comprehensive email handling package; supersedes the :mod:`multifile` module.
+
+
+.. _multifile-objects:
+
+MultiFile Objects
+-----------------
+
+A :class:`MultiFile` instance has the following methods:
+
+
+.. method:: MultiFile.readline(str)
+
+ Read a line. If the line is data (not a section-divider or end-marker or real
+ EOF) return it. If the line matches the most-recently-stacked boundary, return
+ ``''`` and set ``self.last`` to 1 or 0 according as the match is or is not an
+ end-marker. If the line matches any other stacked boundary, raise an error. On
+ encountering end-of-file on the underlying stream object, the method raises
+ :exc:`Error` unless all boundaries have been popped.
+
+
+.. method:: MultiFile.readlines(str)
+
+ Return all lines remaining in this part as a list of strings.
+
+
+.. method:: MultiFile.read()
+
+ Read all lines, up to the next section. Return them as a single (multiline)
+ string. Note that this doesn't take a size argument!
+
+
+.. method:: MultiFile.seek(pos[, whence])
+
+ Seek. Seek indices are relative to the start of the current section. The *pos*
+ and *whence* arguments are interpreted as for a file seek.
+
+
+.. method:: MultiFile.tell()
+
+ Return the file position relative to the start of the current section.
+
+
+.. method:: MultiFile.next()
+
+ Skip lines to the next section (that is, read lines until a section-divider or
+ end-marker has been consumed). Return true if there is such a section, false if
+ an end-marker is seen. Re-enable the most-recently-pushed boundary.
+
+
+.. method:: MultiFile.is_data(str)
+
+ Return true if *str* is data and false if it might be a section boundary. As
+ written, it tests for a prefix other than ``'-``\ ``-'`` at start of line (which
+ all MIME boundaries have) but it is declared so it can be overridden in derived
+ classes.
+
+ Note that this test is used intended as a fast guard for the real boundary
+ tests; if it always returns false it will merely slow processing, not cause it
+ to fail.
+
+
+.. method:: MultiFile.push(str)
+
+ Push a boundary string. When a decorated version of this boundary is found as
+ an input line, it will be interpreted as a section-divider or end-marker
+ (depending on the decoration, see :rfc:`2045`). All subsequent reads will
+ return the empty string to indicate end-of-file, until a call to :meth:`pop`
+ removes the boundary a or :meth:`next` call reenables it.
+
+ It is possible to push more than one boundary. Encountering the
+ most-recently-pushed boundary will return EOF; encountering any other
+ boundary will raise an error.
+
+
+.. method:: MultiFile.pop()
+
+ Pop a section boundary. This boundary will no longer be interpreted as EOF.
+
+
+.. method:: MultiFile.section_divider(str)
+
+ Turn a boundary into a section-divider line. By default, this method
+ prepends ``'--'`` (which MIME section boundaries have) but it is declared so
+ it can be overridden in derived classes. This method need not append LF or
+ CR-LF, as comparison with the result ignores trailing whitespace.
+
+
+.. method:: MultiFile.end_marker(str)
+
+ Turn a boundary string into an end-marker line. By default, this method
+ prepends ``'--'`` and appends ``'--'`` (like a MIME-multipart end-of-message
+ marker) but it is declared so it can be overridden in derived classes. This
+ method need not append LF or CR-LF, as comparison with the result ignores
+ trailing whitespace.
+
+Finally, :class:`MultiFile` instances have two public instance variables:
+
+
+.. attribute:: MultiFile.level
+
+ Nesting depth of the current part.
+
+
+.. attribute:: MultiFile.last
+
+ True if the last end-of-file was for an end-of-message marker.
+
+
+.. _multifile-example:
+
+:class:`MultiFile` Example
+--------------------------
+
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+::
+
+ import mimetools
+ import multifile
+ import StringIO
+
+ def extract_mime_part_matching(stream, mimetype):
+ """Return the first element in a multipart MIME message on stream
+ matching mimetype."""
+
+ msg = mimetools.Message(stream)
+ msgtype = msg.gettype()
+ params = msg.getplist()
+
+ data = StringIO.StringIO()
+ if msgtype[:10] == "multipart/":
+
+ file = multifile.MultiFile(stream)
+ file.push(msg.getparam("boundary"))
+ while file.next():
+ submsg = mimetools.Message(file)
+ try:
+ data = StringIO.StringIO()
+ mimetools.decode(file, data, submsg.getencoding())
+ except ValueError:
+ continue
+ if submsg.gettype() == mimetype:
+ break
+ file.pop()
+ return data.getvalue()
+
diff --git a/Doc/library/mutex.rst b/Doc/library/mutex.rst
new file mode 100644
index 0000000000..523692f066
--- /dev/null
+++ b/Doc/library/mutex.rst
@@ -0,0 +1,62 @@
+
+:mod:`mutex` --- Mutual exclusion support
+=========================================
+
+.. module:: mutex
+ :synopsis: Lock and queue for mutual exclusion.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`mutex` module defines a class that allows mutual-exclusion via
+acquiring and releasing locks. It does not require (or imply) threading or
+multi-tasking, though it could be useful for those purposes.
+
+The :mod:`mutex` module defines the following class:
+
+
+.. class:: mutex()
+
+ Create a new (unlocked) mutex.
+
+ A mutex has two pieces of state --- a "locked" bit and a queue. When the mutex
+ is not locked, the queue is empty. Otherwise, the queue contains zero or more
+ ``(function, argument)`` pairs representing functions (or methods) waiting to
+ acquire the lock. When the mutex is unlocked while the queue is not empty, the
+ first queue entry is removed and its ``function(argument)`` pair called,
+ implying it now has the lock.
+
+ Of course, no multi-threading is implied -- hence the funny interface for
+ :meth:`lock`, where a function is called once the lock is acquired.
+
+
+.. _mutex-objects:
+
+Mutex Objects
+-------------
+
+:class:`mutex` objects have following methods:
+
+
+.. method:: mutex.test()
+
+ Check whether the mutex is locked.
+
+
+.. method:: mutex.testandset()
+
+ "Atomic" test-and-set, grab the lock if it is not set, and return ``True``,
+ otherwise, return ``False``.
+
+
+.. method:: mutex.lock(function, argument)
+
+ Execute ``function(argument)``, unless the mutex is locked. In the case it is
+ locked, place the function and argument on the queue. See :meth:`unlock` for
+ explanation of when ``function(argument)`` is executed in that case.
+
+
+.. method:: mutex.unlock()
+
+ Unlock the mutex if queue is empty, otherwise execute the first element in the
+ queue.
+
diff --git a/Doc/library/netdata.rst b/Doc/library/netdata.rst
new file mode 100644
index 0000000000..add01d2a27
--- /dev/null
+++ b/Doc/library/netdata.rst
@@ -0,0 +1,26 @@
+
+.. _netdata:
+
+**********************
+Internet Data Handling
+**********************
+
+This chapter describes modules which support handling data formats commonly used
+on the Internet.
+
+
+.. toctree::
+
+ email.rst
+ mailcap.rst
+ mailbox.rst
+ mhlib.rst
+ mimetools.rst
+ mimetypes.rst
+ multifile.rst
+ rfc822.rst
+ base64.rst
+ binhex.rst
+ binascii.rst
+ quopri.rst
+ uu.rst
diff --git a/Doc/library/netrc.rst b/Doc/library/netrc.rst
new file mode 100644
index 0000000000..bf3d92ec8d
--- /dev/null
+++ b/Doc/library/netrc.rst
@@ -0,0 +1,78 @@
+
+:mod:`netrc` --- netrc file processing
+======================================
+
+.. module:: netrc
+ :synopsis: Loading of .netrc files.
+.. moduleauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+
+
+.. % Note the \protect needed for \file... ;-(
+
+.. versionadded:: 1.5.2
+
+The :class:`netrc` class parses and encapsulates the netrc file format used by
+the Unix :program:`ftp` program and other FTP clients.
+
+
+.. class:: netrc([file])
+
+ A :class:`netrc` instance or subclass instance encapsulates data from a netrc
+ file. The initialization argument, if present, specifies the file to parse. If
+ no argument is given, the file :file:`.netrc` in the user's home directory will
+ be read. Parse errors will raise :exc:`NetrcParseError` with diagnostic
+ information including the file name, line number, and terminating token.
+
+
+.. exception:: NetrcParseError
+
+ Exception raised by the :class:`netrc` class when syntactical errors are
+ encountered in source text. Instances of this exception provide three
+ interesting attributes: :attr:`msg` is a textual explanation of the error,
+ :attr:`filename` is the name of the source file, and :attr:`lineno` gives the
+ line number on which the error was found.
+
+
+.. _netrc-objects:
+
+netrc Objects
+-------------
+
+A :class:`netrc` instance has the following methods:
+
+
+.. method:: netrc.authenticators(host)
+
+ Return a 3-tuple ``(login, account, password)`` of authenticators for *host*.
+ If the netrc file did not contain an entry for the given host, return the tuple
+ associated with the 'default' entry. If neither matching host nor default entry
+ is available, return ``None``.
+
+
+.. method:: netrc.__repr__()
+
+ Dump the class data as a string in the format of a netrc file. (This discards
+ comments and may reorder the entries.)
+
+Instances of :class:`netrc` have public instance variables:
+
+
+.. attribute:: netrc.hosts
+
+ Dictionary mapping host names to ``(login, account, password)`` tuples. The
+ 'default' entry, if any, is represented as a pseudo-host by that name.
+
+
+.. attribute:: netrc.macros
+
+ Dictionary mapping macro names to string lists.
+
+.. note::
+
+ Passwords are limited to a subset of the ASCII character set. Versions of
+ this module prior to 2.3 were extremely limited. Starting with 2.3, all
+ ASCII punctuation is allowed in passwords. However, note that whitespace and
+ non-printable characters are not allowed in passwords. This is a limitation
+ of the way the .netrc file is parsed and may be removed in the future.
+
diff --git a/Doc/library/new.rst b/Doc/library/new.rst
new file mode 100644
index 0000000000..852fb58126
--- /dev/null
+++ b/Doc/library/new.rst
@@ -0,0 +1,53 @@
+
+:mod:`new` --- Creation of runtime internal objects
+===================================================
+
+.. module:: new
+ :synopsis: Interface to the creation of runtime implementation objects.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`new` module allows an interface to the interpreter object creation
+functions. This is for use primarily in marshal-type functions, when a new
+object needs to be created "magically" and not by using the regular creation
+functions. This module provides a low-level interface to the interpreter, so
+care must be exercised when using this module. It is possible to supply
+non-sensical arguments which crash the interpreter when the object is used.
+
+The :mod:`new` module defines the following functions:
+
+
+.. function:: instancemethod(function, instance, class)
+
+ This function will return a method object, bound to *instance*, or unbound if
+ *instance* is ``None``. *function* must be callable.
+
+
+.. function:: function(code, globals[, name[, argdefs[, closure]]])
+
+ Returns a (Python) function with the given code and globals. If *name* is given,
+ it must be a string or ``None``. If it is a string, the function will have the
+ given name, otherwise the function name will be taken from ``code.co_name``. If
+ *argdefs* is given, it must be a tuple and will be used to determine the default
+ values of parameters. If *closure* is given, it must be ``None`` or a tuple of
+ cell objects containing objects to bind to the names in ``code.co_freevars``.
+
+
+.. function:: code(argcount, nlocals, stacksize, flags, codestring, constants, names, varnames, filename, name, firstlineno, lnotab)
+
+ This function is an interface to the :cfunc:`PyCode_New` C function.
+
+ .. % XXX This is still undocumented!!!!!!!!!!!
+
+
+.. function:: module(name[, doc])
+
+ This function returns a new module object with name *name*. *name* must be a
+ string. The optional *doc* argument can have any type.
+
+
+.. function:: classobj(name, baseclasses, dict)
+
+ This function returns a new class object, with name *name*, derived from
+ *baseclasses* (which should be a tuple of classes) and with namespace *dict*.
+
diff --git a/Doc/library/nis.rst b/Doc/library/nis.rst
new file mode 100644
index 0000000000..77684bf28e
--- /dev/null
+++ b/Doc/library/nis.rst
@@ -0,0 +1,68 @@
+
+:mod:`nis` --- Interface to Sun's NIS (Yellow Pages)
+====================================================
+
+.. module:: nis
+ :platform: Unix
+ :synopsis: Interface to Sun's NIS (Yellow Pages) library.
+.. moduleauthor:: Fred Gansevles <Fred.Gansevles@cs.utwente.nl>
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`nis` module gives a thin wrapper around the NIS library, useful for
+central administration of several hosts.
+
+Because NIS exists only on Unix systems, this module is only available for Unix.
+
+The :mod:`nis` module defines the following functions:
+
+
+.. function:: match(key, mapname[, domain=default_domain])
+
+ Return the match for *key* in map *mapname*, or raise an error
+ (:exc:`nis.error`) if there is none. Both should be strings, *key* is 8-bit
+ clean. Return value is an arbitrary array of bytes (may contain ``NULL`` and
+ other joys).
+
+ Note that *mapname* is first checked if it is an alias to another name.
+
+ .. versionchanged:: 2.5
+ The *domain* argument allows to override the NIS domain used for the lookup. If
+ unspecified, lookup is in the default NIS domain.
+
+
+.. function:: cat(mapname[, domain=default_domain])
+
+ Return a dictionary mapping *key* to *value* such that ``match(key,
+ mapname)==value``. Note that both keys and values of the dictionary are
+ arbitrary arrays of bytes.
+
+ Note that *mapname* is first checked if it is an alias to another name.
+
+ .. versionchanged:: 2.5
+ The *domain* argument allows to override the NIS domain used for the lookup. If
+ unspecified, lookup is in the default NIS domain.
+
+
+.. function:: maps([domain=default_domain])
+
+ Return a list of all valid maps.
+
+ .. versionchanged:: 2.5
+ The *domain* argument allows to override the NIS domain used for the lookup. If
+ unspecified, lookup is in the default NIS domain.
+
+
+.. function:: get_default_domain()
+
+ Return the system default NIS domain.
+
+ .. versionadded:: 2.5
+
+The :mod:`nis` module defines the following exception:
+
+
+.. exception:: error
+
+ An error raised when a NIS function returns an error code.
+
diff --git a/Doc/library/nntplib.rst b/Doc/library/nntplib.rst
new file mode 100644
index 0000000000..5bc947e11d
--- /dev/null
+++ b/Doc/library/nntplib.rst
@@ -0,0 +1,350 @@
+
+:mod:`nntplib` --- NNTP protocol client
+=======================================
+
+.. module:: nntplib
+ :synopsis: NNTP protocol client (requires sockets).
+
+
+.. index::
+ pair: NNTP; protocol
+ single: Network News Transfer Protocol
+
+This module defines the class :class:`NNTP` which implements the client side of
+the NNTP protocol. It can be used to implement a news reader or poster, or
+automated news processors. For more information on NNTP (Network News Transfer
+Protocol), see Internet :rfc:`977`.
+
+Here are two small examples of how it can be used. To list some statistics
+about a newsgroup and print the subjects of the last 10 articles::
+
+ >>> s = NNTP('news.cwi.nl')
+ >>> resp, count, first, last, name = s.group('comp.lang.python')
+ >>> print 'Group', name, 'has', count, 'articles, range', first, 'to', last
+ Group comp.lang.python has 59 articles, range 3742 to 3803
+ >>> resp, subs = s.xhdr('subject', first + '-' + last)
+ >>> for id, sub in subs[-10:]: print id, sub
+ ...
+ 3792 Re: Removing elements from a list while iterating...
+ 3793 Re: Who likes Info files?
+ 3794 Emacs and doc strings
+ 3795 a few questions about the Mac implementation
+ 3796 Re: executable python scripts
+ 3797 Re: executable python scripts
+ 3798 Re: a few questions about the Mac implementation
+ 3799 Re: PROPOSAL: A Generic Python Object Interface for Python C Modules
+ 3802 Re: executable python scripts
+ 3803 Re: \POSIX{} wait and SIGCHLD
+ >>> s.quit()
+ '205 news.cwi.nl closing connection. Goodbye.'
+
+To post an article from a file (this assumes that the article has valid
+headers)::
+
+ >>> s = NNTP('news.cwi.nl')
+ >>> f = open('/tmp/article')
+ >>> s.post(f)
+ '240 Article posted successfully.'
+ >>> s.quit()
+ '205 news.cwi.nl closing connection. Goodbye.'
+
+The module itself defines the following items:
+
+
+.. class:: NNTP(host[, port [, user[, password [, readermode] [, usenetrc]]]])
+
+ Return a new instance of the :class:`NNTP` class, representing a connection
+ to the NNTP server running on host *host*, listening at port *port*. The
+ default *port* is 119. If the optional *user* and *password* are provided,
+ or if suitable credentials are present in :file:`/.netrc` and the optional
+ flag *usenetrc* is true (the default), the ``AUTHINFO USER`` and ``AUTHINFO
+ PASS`` commands are used to identify and authenticate the user to the server.
+ If the optional flag *readermode* is true, then a ``mode reader`` command is
+ sent before authentication is performed. Reader mode is sometimes necessary
+ if you are connecting to an NNTP server on the local machine and intend to
+ call reader-specific commands, such as ``group``. If you get unexpected
+ :exc:`NNTPPermanentError`\ s, you might need to set *readermode*.
+ *readermode* defaults to ``None``. *usenetrc* defaults to ``True``.
+
+ .. versionchanged:: 2.4
+ *usenetrc* argument added.
+
+
+.. exception:: NNTPError
+
+ Derived from the standard exception :exc:`Exception`, this is the base class for
+ all exceptions raised by the :mod:`nntplib` module.
+
+
+.. exception:: NNTPReplyError
+
+ Exception raised when an unexpected reply is received from the server. For
+ backwards compatibility, the exception ``error_reply`` is equivalent to this
+ class.
+
+
+.. exception:: NNTPTemporaryError
+
+ Exception raised when an error code in the range 400--499 is received. For
+ backwards compatibility, the exception ``error_temp`` is equivalent to this
+ class.
+
+
+.. exception:: NNTPPermanentError
+
+ Exception raised when an error code in the range 500--599 is received. For
+ backwards compatibility, the exception ``error_perm`` is equivalent to this
+ class.
+
+
+.. exception:: NNTPProtocolError
+
+ Exception raised when a reply is received from the server that does not begin
+ with a digit in the range 1--5. For backwards compatibility, the exception
+ ``error_proto`` is equivalent to this class.
+
+
+.. exception:: NNTPDataError
+
+ Exception raised when there is some error in the response data. For backwards
+ compatibility, the exception ``error_data`` is equivalent to this class.
+
+
+.. _nntp-objects:
+
+NNTP Objects
+------------
+
+NNTP instances have the following methods. The *response* that is returned as
+the first item in the return tuple of almost all methods is the server's
+response: a string beginning with a three-digit code. If the server's response
+indicates an error, the method raises one of the above exceptions.
+
+
+.. method:: NNTP.getwelcome()
+
+ Return the welcome message sent by the server in reply to the initial
+ connection. (This message sometimes contains disclaimers or help information
+ that may be relevant to the user.)
+
+
+.. method:: NNTP.set_debuglevel(level)
+
+ Set the instance's debugging level. This controls the amount of debugging
+ output printed. The default, ``0``, produces no debugging output. A value of
+ ``1`` produces a moderate amount of debugging output, generally a single line
+ per request or response. A value of ``2`` or higher produces the maximum amount
+ of debugging output, logging each line sent and received on the connection
+ (including message text).
+
+
+.. method:: NNTP.newgroups(date, time, [file])
+
+ Send a ``NEWGROUPS`` command. The *date* argument should be a string of the
+ form ``'yymmdd'`` indicating the date, and *time* should be a string of the form
+ ``'hhmmss'`` indicating the time. Return a pair ``(response, groups)`` where
+ *groups* is a list of group names that are new since the given date and time. If
+ the *file* parameter is supplied, then the output of the ``NEWGROUPS`` command
+ is stored in a file. If *file* is a string, then the method will open a file
+ object with that name, write to it then close it. If *file* is a file object,
+ then it will start calling :meth:`write` on it to store the lines of the command
+ output. If *file* is supplied, then the returned *list* is an empty list.
+
+
+.. method:: NNTP.newnews(group, date, time, [file])
+
+ Send a ``NEWNEWS`` command. Here, *group* is a group name or ``'*'``, and
+ *date* and *time* have the same meaning as for :meth:`newgroups`. Return a pair
+ ``(response, articles)`` where *articles* is a list of message ids. If the
+ *file* parameter is supplied, then the output of the ``NEWNEWS`` command is
+ stored in a file. If *file* is a string, then the method will open a file
+ object with that name, write to it then close it. If *file* is a file object,
+ then it will start calling :meth:`write` on it to store the lines of the command
+ output. If *file* is supplied, then the returned *list* is an empty list.
+
+
+.. method:: NNTP.list([file])
+
+ Send a ``LIST`` command. Return a pair ``(response, list)`` where *list* is a
+ list of tuples. Each tuple has the form ``(group, last, first, flag)``, where
+ *group* is a group name, *last* and *first* are the last and first article
+ numbers (as strings), and *flag* is ``'y'`` if posting is allowed, ``'n'`` if
+ not, and ``'m'`` if the newsgroup is moderated. (Note the ordering: *last*,
+ *first*.) If the *file* parameter is supplied, then the output of the ``LIST``
+ command is stored in a file. If *file* is a string, then the method will open
+ a file object with that name, write to it then close it. If *file* is a file
+ object, then it will start calling :meth:`write` on it to store the lines of the
+ command output. If *file* is supplied, then the returned *list* is an empty
+ list.
+
+
+.. method:: NNTP.descriptions(grouppattern)
+
+ Send a ``LIST NEWSGROUPS`` command, where *grouppattern* is a wildmat string as
+ specified in RFC2980 (it's essentially the same as DOS or UNIX shell wildcard
+ strings). Return a pair ``(response, list)``, where *list* is a list of tuples
+ containing ``(name, title)``.
+
+ .. versionadded:: 2.4
+
+
+.. method:: NNTP.description(group)
+
+ Get a description for a single group *group*. If more than one group matches
+ (if 'group' is a real wildmat string), return the first match. If no group
+ matches, return an empty string.
+
+ This elides the response code from the server. If the response code is needed,
+ use :meth:`descriptions`.
+
+ .. versionadded:: 2.4
+
+
+.. method:: NNTP.group(name)
+
+ Send a ``GROUP`` command, where *name* is the group name. Return a tuple
+ ``(response, count, first, last, name)`` where *count* is the (estimated) number
+ of articles in the group, *first* is the first article number in the group,
+ *last* is the last article number in the group, and *name* is the group name.
+ The numbers are returned as strings.
+
+
+.. method:: NNTP.help([file])
+
+ Send a ``HELP`` command. Return a pair ``(response, list)`` where *list* is a
+ list of help strings. If the *file* parameter is supplied, then the output of
+ the ``HELP`` command is stored in a file. If *file* is a string, then the
+ method will open a file object with that name, write to it then close it. If
+ *file* is a file object, then it will start calling :meth:`write` on it to store
+ the lines of the command output. If *file* is supplied, then the returned *list*
+ is an empty list.
+
+
+.. method:: NNTP.stat(id)
+
+ Send a ``STAT`` command, where *id* is the message id (enclosed in ``'<'`` and
+ ``'>'``) or an article number (as a string). Return a triple ``(response,
+ number, id)`` where *number* is the article number (as a string) and *id* is the
+ message id (enclosed in ``'<'`` and ``'>'``).
+
+
+.. method:: NNTP.next()
+
+ Send a ``NEXT`` command. Return as for :meth:`stat`.
+
+
+.. method:: NNTP.last()
+
+ Send a ``LAST`` command. Return as for :meth:`stat`.
+
+
+.. method:: NNTP.head(id)
+
+ Send a ``HEAD`` command, where *id* has the same meaning as for :meth:`stat`.
+ Return a tuple ``(response, number, id, list)`` where the first three are the
+ same as for :meth:`stat`, and *list* is a list of the article's headers (an
+ uninterpreted list of lines, without trailing newlines).
+
+
+.. method:: NNTP.body(id,[file])
+
+ Send a ``BODY`` command, where *id* has the same meaning as for :meth:`stat`.
+ If the *file* parameter is supplied, then the body is stored in a file. If
+ *file* is a string, then the method will open a file object with that name,
+ write to it then close it. If *file* is a file object, then it will start
+ calling :meth:`write` on it to store the lines of the body. Return as for
+ :meth:`head`. If *file* is supplied, then the returned *list* is an empty list.
+
+
+.. method:: NNTP.article(id)
+
+ Send an ``ARTICLE`` command, where *id* has the same meaning as for
+ :meth:`stat`. Return as for :meth:`head`.
+
+
+.. method:: NNTP.slave()
+
+ Send a ``SLAVE`` command. Return the server's *response*.
+
+
+.. method:: NNTP.xhdr(header, string, [file])
+
+ Send an ``XHDR`` command. This command is not defined in the RFC but is a
+ common extension. The *header* argument is a header keyword, e.g.
+ ``'subject'``. The *string* argument should have the form ``'first-last'``
+ where *first* and *last* are the first and last article numbers to search.
+ Return a pair ``(response, list)``, where *list* is a list of pairs ``(id,
+ text)``, where *id* is an article number (as a string) and *text* is the text of
+ the requested header for that article. If the *file* parameter is supplied, then
+ the output of the ``XHDR`` command is stored in a file. If *file* is a string,
+ then the method will open a file object with that name, write to it then close
+ it. If *file* is a file object, then it will start calling :meth:`write` on it
+ to store the lines of the command output. If *file* is supplied, then the
+ returned *list* is an empty list.
+
+
+.. method:: NNTP.post(file)
+
+ Post an article using the ``POST`` command. The *file* argument is an open file
+ object which is read until EOF using its :meth:`readline` method. It should be
+ a well-formed news article, including the required headers. The :meth:`post`
+ method automatically escapes lines beginning with ``.``.
+
+
+.. method:: NNTP.ihave(id, file)
+
+ Send an ``IHAVE`` command. *id* is a message id (enclosed in ``'<'`` and
+ ``'>'``). If the response is not an error, treat *file* exactly as for the
+ :meth:`post` method.
+
+
+.. method:: NNTP.date()
+
+ Return a triple ``(response, date, time)``, containing the current date and time
+ in a form suitable for the :meth:`newnews` and :meth:`newgroups` methods. This
+ is an optional NNTP extension, and may not be supported by all servers.
+
+
+.. method:: NNTP.xgtitle(name, [file])
+
+ Process an ``XGTITLE`` command, returning a pair ``(response, list)``, where
+ *list* is a list of tuples containing ``(name, title)``. If the *file* parameter
+ is supplied, then the output of the ``XGTITLE`` command is stored in a file.
+ If *file* is a string, then the method will open a file object with that name,
+ write to it then close it. If *file* is a file object, then it will start
+ calling :meth:`write` on it to store the lines of the command output. If *file*
+ is supplied, then the returned *list* is an empty list. This is an optional NNTP
+ extension, and may not be supported by all servers.
+
+ .. % XXX huh? Should that be name, description?
+
+ RFC2980 says "It is suggested that this extension be deprecated". Use
+ :meth:`descriptions` or :meth:`description` instead.
+
+
+.. method:: NNTP.xover(start, end, [file])
+
+ Return a pair ``(resp, list)``. *list* is a list of tuples, one for each
+ article in the range delimited by the *start* and *end* article numbers. Each
+ tuple is of the form ``(article number, subject, poster, date, id, references,
+ size, lines)``. If the *file* parameter is supplied, then the output of the
+ ``XOVER`` command is stored in a file. If *file* is a string, then the method
+ will open a file object with that name, write to it then close it. If *file*
+ is a file object, then it will start calling :meth:`write` on it to store the
+ lines of the command output. If *file* is supplied, then the returned *list* is
+ an empty list. This is an optional NNTP extension, and may not be supported by
+ all servers.
+
+
+.. method:: NNTP.xpath(id)
+
+ Return a pair ``(resp, path)``, where *path* is the directory path to the
+ article with message ID *id*. This is an optional NNTP extension, and may not
+ be supported by all servers.
+
+
+.. method:: NNTP.quit()
+
+ Send a ``QUIT`` command and close the connection. Once this method has been
+ called, no other methods of the NNTP object should be called.
+
diff --git a/Doc/library/numeric.rst b/Doc/library/numeric.rst
new file mode 100644
index 0000000000..0d9d59fbe1
--- /dev/null
+++ b/Doc/library/numeric.rst
@@ -0,0 +1,25 @@
+
+.. _numeric:
+
+********************************
+Numeric and Mathematical Modules
+********************************
+
+The modules described in this chapter provide numeric and math-related functions
+and data types. The :mod:`math` and :mod:`cmath` contain various mathematical
+functions for floating-point and complex numbers. For users more interested in
+decimal accuracy than in speed, the :mod:`decimal` module supports exact
+representations of decimal numbers.
+
+The following modules are documented in this chapter:
+
+
+.. toctree::
+
+ math.rst
+ cmath.rst
+ decimal.rst
+ random.rst
+ itertools.rst
+ functools.rst
+ operator.rst
diff --git a/Doc/library/objects.rst b/Doc/library/objects.rst
new file mode 100644
index 0000000000..c6cc9e454e
--- /dev/null
+++ b/Doc/library/objects.rst
@@ -0,0 +1,32 @@
+
+.. _builtin:
+
+****************
+Built-in Objects
+****************
+
+.. index::
+ pair: built-in; types
+ pair: built-in; exceptions
+ pair: built-in; functions
+ pair: built-in; constants
+ single: symbol table
+
+Names for built-in exceptions and functions and a number of constants are found
+in a separate symbol table. This table is searched last when the interpreter
+looks up the meaning of a name, so local and global user-defined names can
+override built-in names. Built-in types are described together here for easy
+reference. [#]_
+
+The tables in this chapter document the priorities of operators by listing them
+in order of ascending priority (within a table) and grouping operators that have
+the same priority in the same box. Binary operators of the same priority group
+from left to right. (Unary operators group from right to left, but there you
+have no real choice.) See :ref:`operator-summary` for the complete picture on
+operator priorities.
+
+.. rubric:: Footnotes
+
+.. [#] Most descriptions sorely lack explanations of the exceptions that may be raised
+ --- this will be fixed in a future version of this manual.
+
diff --git a/Doc/library/operator.rst b/Doc/library/operator.rst
new file mode 100644
index 0000000000..4e85569072
--- /dev/null
+++ b/Doc/library/operator.rst
@@ -0,0 +1,612 @@
+:mod:`operator` --- Standard operators as functions
+===================================================
+
+.. module:: operator
+ :synopsis: Functions corresponding to the standard operators.
+.. sectionauthor:: Skip Montanaro <skip@automatrix.com>
+
+
+
+The :mod:`operator` module exports a set of functions implemented in C
+corresponding to the intrinsic operators of Python. For example,
+``operator.add(x, y)`` is equivalent to the expression ``x+y``. The function
+names are those used for special class methods; variants without leading and
+trailing ``__`` are also provided for convenience.
+
+The functions fall into categories that perform object comparisons, logical
+operations, mathematical operations, sequence operations, and abstract type
+tests.
+
+The object comparison functions are useful for all objects, and are named after
+the rich comparison operators they support:
+
+
+.. function:: lt(a, b)
+ le(a, b)
+ eq(a, b)
+ ne(a, b)
+ ge(a, b)
+ gt(a, b)
+ __lt__(a, b)
+ __le__(a, b)
+ __eq__(a, b)
+ __ne__(a, b)
+ __ge__(a, b)
+ __gt__(a, b)
+
+ Perform "rich comparisons" between *a* and *b*. Specifically, ``lt(a, b)`` is
+ equivalent to ``a < b``, ``le(a, b)`` is equivalent to ``a <= b``, ``eq(a,
+ b)`` is equivalent to ``a == b``, ``ne(a, b)`` is equivalent to ``a != b``,
+ ``gt(a, b)`` is equivalent to ``a > b`` and ``ge(a, b)`` is equivalent to ``a
+ >= b``. Note that unlike the built-in :func:`cmp`, these functions can
+ return any value, which may or may not be interpretable as a Boolean value.
+ See :ref:`comparisons` for more information about rich comparisons.
+
+ .. versionadded:: 2.2
+
+The logical operations are also generally applicable to all objects, and support
+truth tests, identity tests, and boolean operations:
+
+
+.. function:: not_(o)
+ __not__(o)
+
+ Return the outcome of :keyword:`not` *o*. (Note that there is no
+ :meth:`__not__` method for object instances; only the interpreter core defines
+ this operation. The result is affected by the :meth:`__bool__` and
+ :meth:`__len__` methods.)
+
+
+.. function:: truth(o)
+
+ Return :const:`True` if *o* is true, and :const:`False` otherwise. This is
+ equivalent to using the :class:`bool` constructor.
+
+
+.. function:: is_(a, b)
+
+ Return ``a is b``. Tests object identity.
+
+ .. versionadded:: 2.3
+
+
+.. function:: is_not(a, b)
+
+ Return ``a is not b``. Tests object identity.
+
+ .. versionadded:: 2.3
+
+The mathematical and bitwise operations are the most numerous:
+
+
+.. function:: abs(o)
+ __abs__(o)
+
+ Return the absolute value of *o*.
+
+
+.. function:: add(a, b)
+ __add__(a, b)
+
+ Return ``a + b``, for *a* and *b* numbers.
+
+
+.. function:: and_(a, b)
+ __and__(a, b)
+
+ Return the bitwise and of *a* and *b*.
+
+
+.. function:: div(a, b)
+ __div__(a, b)
+
+ Return ``a / b`` when ``__future__.division`` is not in effect. This is
+ also known as "classic" division.
+
+
+.. function:: floordiv(a, b)
+ __floordiv__(a, b)
+
+ Return ``a // b``.
+
+ .. versionadded:: 2.2
+
+
+.. function:: inv(o)
+ invert(o)
+ __inv__(o)
+ __invert__(o)
+
+ Return the bitwise inverse of the number *o*. This is equivalent to ``~o``.
+
+ .. versionadded:: 2.0
+ The names :func:`invert` and :func:`__invert__`.
+
+
+.. function:: lshift(a, b)
+ __lshift__(a, b)
+
+ Return *a* shifted left by *b*.
+
+
+.. function:: mod(a, b)
+ __mod__(a, b)
+
+ Return ``a % b``.
+
+
+.. function:: mul(a, b)
+ __mul__(a, b)
+
+ Return ``a * b``, for *a* and *b* numbers.
+
+
+.. function:: neg(o)
+ __neg__(o)
+
+ Return *o* negated.
+
+
+.. function:: or_(a, b)
+ __or__(a, b)
+
+ Return the bitwise or of *a* and *b*.
+
+
+.. function:: pos(o)
+ __pos__(o)
+
+ Return *o* positive.
+
+
+.. function:: pow(a, b)
+ __pow__(a, b)
+
+ Return ``a ** b``, for *a* and *b* numbers.
+
+ .. versionadded:: 2.3
+
+
+.. function:: rshift(a, b)
+ __rshift__(a, b)
+
+ Return *a* shifted right by *b*.
+
+
+.. function:: sub(a, b)
+ __sub__(a, b)
+
+ Return ``a - b``.
+
+
+.. function:: truediv(a, b)
+ __truediv__(a, b)
+
+ Return ``a / b`` when ``__future__.division`` is in effect. This is also
+ known as "true" division.
+
+ .. versionadded:: 2.2
+
+
+.. function:: xor(a, b)
+ __xor__(a, b)
+
+ Return the bitwise exclusive or of *a* and *b*.
+
+
+.. function:: index(a)
+ __index__(a)
+
+ Return *a* converted to an integer. Equivalent to ``a.__index__()``.
+
+ .. versionadded:: 2.5
+
+
+Operations which work with sequences include:
+
+.. function:: concat(a, b)
+ __concat__(a, b)
+
+ Return ``a + b`` for *a* and *b* sequences.
+
+
+.. function:: contains(a, b)
+ __contains__(a, b)
+
+ Return the outcome of the test ``b in a``. Note the reversed operands.
+
+ .. versionadded:: 2.0
+ The name :func:`__contains__`.
+
+
+.. function:: countOf(a, b)
+
+ Return the number of occurrences of *b* in *a*.
+
+
+.. function:: delitem(a, b)
+ __delitem__(a, b)
+
+ Remove the value of *a* at index *b*.
+
+
+.. function:: delslice(a, b, c)
+ __delslice__(a, b, c)
+
+ Delete the slice of *a* from index *b* to index *c-1*.
+
+
+.. function:: getitem(a, b)
+ __getitem__(a, b)
+
+ Return the value of *a* at index *b*.
+
+
+.. function:: getslice(a, b, c)
+ __getslice__(a, b, c)
+
+ Return the slice of *a* from index *b* to index *c-1*.
+
+
+.. function:: indexOf(a, b)
+
+ Return the index of the first of occurrence of *b* in *a*.
+
+
+.. function:: repeat(a, b)
+ __repeat__(a, b)
+
+ Return ``a * b`` where *a* is a sequence and *b* is an integer.
+
+
+.. function:: sequenceIncludes(...)
+
+ .. deprecated:: 2.0
+ Use :func:`contains` instead.
+
+ Alias for :func:`contains`.
+
+
+.. function:: setitem(a, b, c)
+ __setitem__(a, b, c)
+
+ Set the value of *a* at index *b* to *c*.
+
+
+.. function:: setslice(a, b, c, v)
+ __setslice__(a, b, c, v)
+
+ Set the slice of *a* from index *b* to index *c-1* to the sequence *v*.
+
+Many operations have an "in-place" version. The following functions provide a
+more primitive access to in-place operators than the usual syntax does; for
+example, the statement ``x += y`` is equivalent to ``x = operator.iadd(x, y)``.
+Another way to put it is to say that ``z = operator.iadd(x, y)`` is equivalent
+to the compound statement ``z = x; z += y``.
+
+
+.. function:: iadd(a, b)
+ __iadd__(a, b)
+
+ ``a = iadd(a, b)`` is equivalent to ``a += b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: iand(a, b)
+ __iand__(a, b)
+
+ ``a = iand(a, b)`` is equivalent to ``a &= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: iconcat(a, b)
+ __iconcat__(a, b)
+
+ ``a = iconcat(a, b)`` is equivalent to ``a += b`` for *a* and *b* sequences.
+
+ .. versionadded:: 2.5
+
+
+.. function:: idiv(a, b)
+ __idiv__(a, b)
+
+ ``a = idiv(a, b)`` is equivalent to ``a /= b`` when ``__future__.division`` is
+ not in effect.
+
+ .. versionadded:: 2.5
+
+
+.. function:: ifloordiv(a, b)
+ __ifloordiv__(a, b)
+
+ ``a = ifloordiv(a, b)`` is equivalent to ``a //= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: ilshift(a, b)
+ __ilshift__(a, b)
+
+ ``a = ilshift(a, b)`` is equivalent to ``a <``\ ``<= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: imod(a, b)
+ __imod__(a, b)
+
+ ``a = imod(a, b)`` is equivalent to ``a %= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: imul(a, b)
+ __imul__(a, b)
+
+ ``a = imul(a, b)`` is equivalent to ``a *= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: ior(a, b)
+ __ior__(a, b)
+
+ ``a = ior(a, b)`` is equivalent to ``a |= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: ipow(a, b)
+ __ipow__(a, b)
+
+ ``a = ipow(a, b)`` is equivalent to ``a **= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: irepeat(a, b)
+ __irepeat__(a, b)
+
+ ``a = irepeat(a, b)`` is equivalent to ``a *= b`` where *a* is a sequence and
+ *b* is an integer.
+
+ .. versionadded:: 2.5
+
+
+.. function:: irshift(a, b)
+ __irshift__(a, b)
+
+ ``a = irshift(a, b)`` is equivalent to ``a >>= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: isub(a, b)
+ __isub__(a, b)
+
+ ``a = isub(a, b)`` is equivalent to ``a -= b``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: itruediv(a, b)
+ __itruediv__(a, b)
+
+ ``a = itruediv(a, b)`` is equivalent to ``a /= b`` when ``__future__.division``
+ is in effect.
+
+ .. versionadded:: 2.5
+
+
+.. function:: ixor(a, b)
+ __ixor__(a, b)
+
+ ``a = ixor(a, b)`` is equivalent to ``a ^= b``.
+
+ .. versionadded:: 2.5
+
+
+The :mod:`operator` module also defines a few predicates to test the type of
+objects.
+
+.. note::
+
+ Be careful not to misinterpret the results of these functions; only
+ :func:`isCallable` has any measure of reliability with instance objects.
+ For example::
+
+ >>> class C:
+ ... pass
+ ...
+ >>> import operator
+ >>> o = C()
+ >>> operator.isMappingType(o)
+ True
+
+
+.. function:: isCallable(o)
+
+ .. deprecated:: 2.0
+ Use the :func:`callable` built-in function instead.
+
+ Returns true if the object *o* can be called like a function, otherwise it
+ returns false. True is returned for functions, bound and unbound methods, class
+ objects, and instance objects which support the :meth:`__call__` method.
+
+
+.. function:: isMappingType(o)
+
+ Returns true if the object *o* supports the mapping interface. This is true for
+ dictionaries and all instance objects defining :meth:`__getitem__`.
+
+ .. warning::
+
+ There is no reliable way to test if an instance supports the complete mapping
+ protocol since the interface itself is ill-defined. This makes this test less
+ useful than it otherwise might be.
+
+
+.. function:: isNumberType(o)
+
+ Returns true if the object *o* represents a number. This is true for all
+ numeric types implemented in C.
+
+ .. warning::
+
+ There is no reliable way to test if an instance supports the complete numeric
+ interface since the interface itself is ill-defined. This makes this test less
+ useful than it otherwise might be.
+
+
+.. function:: isSequenceType(o)
+
+ Returns true if the object *o* supports the sequence protocol. This returns true
+ for all objects which define sequence methods in C, and for all instance objects
+ defining :meth:`__getitem__`.
+
+ .. warning::
+
+ There is no reliable way to test if an instance supports the complete sequence
+ interface since the interface itself is ill-defined. This makes this test less
+ useful than it otherwise might be.
+
+Example: Build a dictionary that maps the ordinals from ``0`` to ``255`` to
+their character equivalents. ::
+
+ >>> import operator
+ >>> d = {}
+ >>> keys = range(256)
+ >>> vals = map(chr, keys)
+ >>> map(operator.setitem, [d]*len(keys), keys, vals)
+
+.. XXX: find a better, readable, example
+
+The :mod:`operator` module also defines tools for generalized attribute and item
+lookups. These are useful for making fast field extractors as arguments for
+:func:`map`, :func:`sorted`, :meth:`itertools.groupby`, or other functions that
+expect a function argument.
+
+
+.. function:: attrgetter(attr[, args...])
+
+ Return a callable object that fetches *attr* from its operand. If more than one
+ attribute is requested, returns a tuple of attributes. After,
+ ``f=attrgetter('name')``, the call ``f(b)`` returns ``b.name``. After,
+ ``f=attrgetter('name', 'date')``, the call ``f(b)`` returns ``(b.name,
+ b.date)``.
+
+ .. versionadded:: 2.4
+
+ .. versionchanged:: 2.5
+ Added support for multiple attributes.
+
+
+.. function:: itemgetter(item[, args...])
+
+ Return a callable object that fetches *item* from its operand. If more than one
+ item is requested, returns a tuple of items. After, ``f=itemgetter(2)``, the
+ call ``f(b)`` returns ``b[2]``. After, ``f=itemgetter(2,5,3)``, the call
+ ``f(b)`` returns ``(b[2], b[5], b[3])``.
+
+ .. versionadded:: 2.4
+
+ .. versionchanged:: 2.5
+ Added support for multiple item extraction.
+
+Examples::
+
+ >>> from operator import itemgetter
+ >>> inventory = [('apple', 3), ('banana', 2), ('pear', 5), ('orange', 1)]
+ >>> getcount = itemgetter(1)
+ >>> map(getcount, inventory)
+ [3, 2, 5, 1]
+ >>> sorted(inventory, key=getcount)
+ [('orange', 1), ('banana', 2), ('apple', 3), ('pear', 5)]
+
+
+.. _operator-map:
+
+Mapping Operators to Functions
+------------------------------
+
+This table shows how abstract operations correspond to operator symbols in the
+Python syntax and the functions in the :mod:`operator` module.
+
++-----------------------+-------------------------+---------------------------------+
+| Operation | Syntax | Function |
++=======================+=========================+=================================+
+| Addition | ``a + b`` | ``add(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Concatenation | ``seq1 + seq2`` | ``concat(seq1, seq2)`` |
++-----------------------+-------------------------+---------------------------------+
+| Containment Test | ``o in seq`` | ``contains(seq, o)`` |
++-----------------------+-------------------------+---------------------------------+
+| Division | ``a / b`` | ``div(a, b)`` (without |
+| | | ``__future__.division``) |
++-----------------------+-------------------------+---------------------------------+
+| Division | ``a / b`` | ``truediv(a, b)`` (with |
+| | | ``__future__.division``) |
++-----------------------+-------------------------+---------------------------------+
+| Division | ``a // b`` | ``floordiv(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Bitwise And | ``a & b`` | ``and_(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Bitwise Exclusive Or | ``a ^ b`` | ``xor(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Bitwise Inversion | ``~ a`` | ``invert(a)`` |
++-----------------------+-------------------------+---------------------------------+
+| Bitwise Or | ``a | b`` | ``or_(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Exponentiation | ``a ** b`` | ``pow(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Identity | ``a is b`` | ``is_(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Identity | ``a is not b`` | ``is_not(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Indexed Assignment | ``o[k] = v`` | ``setitem(o, k, v)`` |
++-----------------------+-------------------------+---------------------------------+
+| Indexed Deletion | ``del o[k]`` | ``delitem(o, k)`` |
++-----------------------+-------------------------+---------------------------------+
+| Indexing | ``o[k]`` | ``getitem(o, k)`` |
++-----------------------+-------------------------+---------------------------------+
+| Left Shift | ``a << b`` | ``lshift(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Modulo | ``a % b`` | ``mod(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Multiplication | ``a * b`` | ``mul(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Negation (Arithmetic) | ``- a`` | ``neg(a)`` |
++-----------------------+-------------------------+---------------------------------+
+| Negation (Logical) | ``not a`` | ``not_(a)`` |
++-----------------------+-------------------------+---------------------------------+
+| Right Shift | ``a >> b`` | ``rshift(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Sequence Repitition | ``seq * i`` | ``repeat(seq, i)`` |
++-----------------------+-------------------------+---------------------------------+
+| Slice Assignment | ``seq[i:j] = values`` | ``setslice(seq, i, j, values)`` |
++-----------------------+-------------------------+---------------------------------+
+| Slice Deletion | ``del seq[i:j]`` | ``delslice(seq, i, j)`` |
++-----------------------+-------------------------+---------------------------------+
+| Slicing | ``seq[i:j]`` | ``getslice(seq, i, j)`` |
++-----------------------+-------------------------+---------------------------------+
+| String Formatting | ``s % o`` | ``mod(s, o)`` |
++-----------------------+-------------------------+---------------------------------+
+| Subtraction | ``a - b`` | ``sub(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Truth Test | ``o`` | ``truth(o)`` |
++-----------------------+-------------------------+---------------------------------+
+| Ordering | ``a < b`` | ``lt(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Ordering | ``a <= b`` | ``le(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Equality | ``a == b`` | ``eq(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Difference | ``a != b`` | ``ne(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Ordering | ``a >= b`` | ``ge(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+| Ordering | ``a > b`` | ``gt(a, b)`` |
++-----------------------+-------------------------+---------------------------------+
+
diff --git a/Doc/library/optparse.rst b/Doc/library/optparse.rst
new file mode 100644
index 0000000000..cfcd8a6599
--- /dev/null
+++ b/Doc/library/optparse.rst
@@ -0,0 +1,1827 @@
+.. % THIS FILE IS AUTO-GENERATED! DO NOT EDIT!
+.. % (Your changes will be lost the next time it is generated.)
+
+
+:mod:`optparse` --- More powerful command line option parser
+============================================================
+
+.. module:: optparse
+ :synopsis: More convenient, flexible, and powerful command-line parsing library.
+.. moduleauthor:: Greg Ward <gward@python.net>
+
+
+.. versionadded:: 2.3
+
+.. sectionauthor:: Greg Ward <gward@python.net>
+
+
+``optparse`` is a more convenient, flexible, and powerful library for parsing
+command-line options than ``getopt``. ``optparse`` uses a more declarative
+style of command-line parsing: you create an instance of :class:`OptionParser`,
+populate it with options, and parse the command line. ``optparse`` allows users
+to specify options in the conventional GNU/POSIX syntax, and additionally
+generates usage and help messages for you.
+
+.. % An intro blurb used only when generating LaTeX docs for the Python
+.. % manual (based on README.txt).
+
+Here's an example of using ``optparse`` in a simple script::
+
+ from optparse import OptionParser
+ [...]
+ parser = OptionParser()
+ parser.add_option("-f", "--file", dest="filename",
+ help="write report to FILE", metavar="FILE")
+ parser.add_option("-q", "--quiet",
+ action="store_false", dest="verbose", default=True,
+ help="don't print status messages to stdout")
+
+ (options, args) = parser.parse_args()
+
+With these few lines of code, users of your script can now do the "usual thing"
+on the command-line, for example::
+
+ <yourscript> --file=outfile -q
+
+As it parses the command line, ``optparse`` sets attributes of the ``options``
+object returned by :meth:`parse_args` based on user-supplied command-line
+values. When :meth:`parse_args` returns from parsing this command line,
+``options.filename`` will be ``"outfile"`` and ``options.verbose`` will be
+``False``. ``optparse`` supports both long and short options, allows short
+options to be merged together, and allows options to be associated with their
+arguments in a variety of ways. Thus, the following command lines are all
+equivalent to the above example::
+
+ <yourscript> -f outfile --quiet
+ <yourscript> --quiet --file outfile
+ <yourscript> -q -foutfile
+ <yourscript> -qfoutfile
+
+Additionally, users can run one of ::
+
+ <yourscript> -h
+ <yourscript> --help
+
+and ``optparse`` will print out a brief summary of your script's options::
+
+ usage: <yourscript> [options]
+
+ options:
+ -h, --help show this help message and exit
+ -f FILE, --file=FILE write report to FILE
+ -q, --quiet don't print status messages to stdout
+
+where the value of *yourscript* is determined at runtime (normally from
+``sys.argv[0]``).
+
+.. % $Id: intro.txt 413 2004-09-28 00:59:13Z greg $
+
+
+.. _optparse-background:
+
+Background
+----------
+
+:mod:`optparse` was explicitly designed to encourage the creation of programs
+with straightforward, conventional command-line interfaces. To that end, it
+supports only the most common command-line syntax and semantics conventionally
+used under Unix. If you are unfamiliar with these conventions, read this
+section to acquaint yourself with them.
+
+
+.. _optparse-terminology:
+
+Terminology
+^^^^^^^^^^^
+
+argument
+ a string entered on the command-line, and passed by the shell to ``execl()`` or
+ ``execv()``. In Python, arguments are elements of ``sys.argv[1:]``
+ (``sys.argv[0]`` is the name of the program being executed). Unix shells also
+ use the term "word".
+
+ It is occasionally desirable to substitute an argument list other than
+ ``sys.argv[1:]``, so you should read "argument" as "an element of
+ ``sys.argv[1:]``, or of some other list provided as a substitute for
+ ``sys.argv[1:]``".
+
+option
+ an argument used to supply extra information to guide or customize the execution
+ of a program. There are many different syntaxes for options; the traditional
+ Unix syntax is a hyphen ("-") followed by a single letter, e.g. ``"-x"`` or
+ ``"-F"``. Also, traditional Unix syntax allows multiple options to be merged
+ into a single argument, e.g. ``"-x -F"`` is equivalent to ``"-xF"``. The GNU
+ project introduced ``"--"`` followed by a series of hyphen-separated words, e.g.
+ ``"--file"`` or ``"--dry-run"``. These are the only two option syntaxes
+ provided by :mod:`optparse`.
+
+ Some other option syntaxes that the world has seen include:
+
+ * a hyphen followed by a few letters, e.g. ``"-pf"`` (this is *not* the same
+ as multiple options merged into a single argument)
+
+ * a hyphen followed by a whole word, e.g. ``"-file"`` (this is technically
+ equivalent to the previous syntax, but they aren't usually seen in the same
+ program)
+
+ * a plus sign followed by a single letter, or a few letters, or a word, e.g.
+ ``"+f"``, ``"+rgb"``
+
+ * a slash followed by a letter, or a few letters, or a word, e.g. ``"/f"``,
+ ``"/file"``
+
+ These option syntaxes are not supported by :mod:`optparse`, and they never will
+ be. This is deliberate: the first three are non-standard on any environment,
+ and the last only makes sense if you're exclusively targeting VMS, MS-DOS,
+ and/or Windows.
+
+option argument
+ an argument that follows an option, is closely associated with that option, and
+ is consumed from the argument list when that option is. With :mod:`optparse`,
+ option arguments may either be in a separate argument from their option::
+
+ -f foo
+ --file foo
+
+ or included in the same argument::
+
+ -ffoo
+ --file=foo
+
+ Typically, a given option either takes an argument or it doesn't. Lots of people
+ want an "optional option arguments" feature, meaning that some options will take
+ an argument if they see it, and won't if they don't. This is somewhat
+ controversial, because it makes parsing ambiguous: if ``"-a"`` takes an optional
+ argument and ``"-b"`` is another option entirely, how do we interpret ``"-ab"``?
+ Because of this ambiguity, :mod:`optparse` does not support this feature.
+
+positional argument
+ something leftover in the argument list after options have been parsed, i.e.
+ after options and their arguments have been parsed and removed from the argument
+ list.
+
+required option
+ an option that must be supplied on the command-line; note that the phrase
+ "required option" is self-contradictory in English. :mod:`optparse` doesn't
+ prevent you from implementing required options, but doesn't give you much help
+ at it either. See ``examples/required_1.py`` and ``examples/required_2.py`` in
+ the :mod:`optparse` source distribution for two ways to implement required
+ options with :mod:`optparse`.
+
+For example, consider this hypothetical command-line::
+
+ prog -v --report /tmp/report.txt foo bar
+
+``"-v"`` and ``"--report"`` are both options. Assuming that :option:`--report`
+takes one argument, ``"/tmp/report.txt"`` is an option argument. ``"foo"`` and
+``"bar"`` are positional arguments.
+
+
+.. _optparse-what-options-for:
+
+What are options for?
+^^^^^^^^^^^^^^^^^^^^^
+
+Options are used to provide extra information to tune or customize the execution
+of a program. In case it wasn't clear, options are usually *optional*. A
+program should be able to run just fine with no options whatsoever. (Pick a
+random program from the Unix or GNU toolsets. Can it run without any options at
+all and still make sense? The main exceptions are ``find``, ``tar``, and
+``dd``\ ---all of which are mutant oddballs that have been rightly criticized
+for their non-standard syntax and confusing interfaces.)
+
+Lots of people want their programs to have "required options". Think about it.
+If it's required, then it's *not optional*! If there is a piece of information
+that your program absolutely requires in order to run successfully, that's what
+positional arguments are for.
+
+As an example of good command-line interface design, consider the humble ``cp``
+utility, for copying files. It doesn't make much sense to try to copy files
+without supplying a destination and at least one source. Hence, ``cp`` fails if
+you run it with no arguments. However, it has a flexible, useful syntax that
+does not require any options at all::
+
+ cp SOURCE DEST
+ cp SOURCE ... DEST-DIR
+
+You can get pretty far with just that. Most ``cp`` implementations provide a
+bunch of options to tweak exactly how the files are copied: you can preserve
+mode and modification time, avoid following symlinks, ask before clobbering
+existing files, etc. But none of this distracts from the core mission of
+``cp``, which is to copy either one file to another, or several files to another
+directory.
+
+
+.. _optparse-what-positional-arguments-for:
+
+What are positional arguments for?
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Positional arguments are for those pieces of information that your program
+absolutely, positively requires to run.
+
+A good user interface should have as few absolute requirements as possible. If
+your program requires 17 distinct pieces of information in order to run
+successfully, it doesn't much matter *how* you get that information from the
+user---most people will give up and walk away before they successfully run the
+program. This applies whether the user interface is a command-line, a
+configuration file, or a GUI: if you make that many demands on your users, most
+of them will simply give up.
+
+In short, try to minimize the amount of information that users are absolutely
+required to supply---use sensible defaults whenever possible. Of course, you
+also want to make your programs reasonably flexible. That's what options are
+for. Again, it doesn't matter if they are entries in a config file, widgets in
+the "Preferences" dialog of a GUI, or command-line options---the more options
+you implement, the more flexible your program is, and the more complicated its
+implementation becomes. Too much flexibility has drawbacks as well, of course;
+too many options can overwhelm users and make your code much harder to maintain.
+
+.. % $Id: tao.txt 413 2004-09-28 00:59:13Z greg $
+
+
+.. _optparse-tutorial:
+
+Tutorial
+--------
+
+While :mod:`optparse` is quite flexible and powerful, it's also straightforward
+to use in most cases. This section covers the code patterns that are common to
+any :mod:`optparse`\ -based program.
+
+First, you need to import the OptionParser class; then, early in the main
+program, create an OptionParser instance::
+
+ from optparse import OptionParser
+ [...]
+ parser = OptionParser()
+
+Then you can start defining options. The basic syntax is::
+
+ parser.add_option(opt_str, ...,
+ attr=value, ...)
+
+Each option has one or more option strings, such as ``"-f"`` or ``"--file"``,
+and several option attributes that tell :mod:`optparse` what to expect and what
+to do when it encounters that option on the command line.
+
+Typically, each option will have one short option string and one long option
+string, e.g.::
+
+ parser.add_option("-f", "--file", ...)
+
+You're free to define as many short option strings and as many long option
+strings as you like (including zero), as long as there is at least one option
+string overall.
+
+The option strings passed to :meth:`add_option` are effectively labels for the
+option defined by that call. For brevity, we will frequently refer to
+*encountering an option* on the command line; in reality, :mod:`optparse`
+encounters *option strings* and looks up options from them.
+
+Once all of your options are defined, instruct :mod:`optparse` to parse your
+program's command line::
+
+ (options, args) = parser.parse_args()
+
+(If you like, you can pass a custom argument list to :meth:`parse_args`, but
+that's rarely necessary: by default it uses ``sys.argv[1:]``.)
+
+:meth:`parse_args` returns two values:
+
+* ``options``, an object containing values for all of your options---e.g. if
+ ``"--file"`` takes a single string argument, then ``options.file`` will be the
+ filename supplied by the user, or ``None`` if the user did not supply that
+ option
+
+* ``args``, the list of positional arguments leftover after parsing options
+
+This tutorial section only covers the four most important option attributes:
+:attr:`action`, :attr:`type`, :attr:`dest` (destination), and :attr:`help`. Of
+these, :attr:`action` is the most fundamental.
+
+
+.. _optparse-understanding-option-actions:
+
+Understanding option actions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Actions tell :mod:`optparse` what to do when it encounters an option on the
+command line. There is a fixed set of actions hard-coded into :mod:`optparse`;
+adding new actions is an advanced topic covered in section
+:ref:`optparse-extending-optparse`. Most actions tell
+:mod:`optparse` to store a value in some variable---for example, take a string
+from the command line and store it in an attribute of ``options``.
+
+If you don't specify an option action, :mod:`optparse` defaults to ``store``.
+
+
+.. _optparse-store-action:
+
+The store action
+^^^^^^^^^^^^^^^^
+
+The most common option action is ``store``, which tells :mod:`optparse` to take
+the next argument (or the remainder of the current argument), ensure that it is
+of the correct type, and store it to your chosen destination.
+
+For example::
+
+ parser.add_option("-f", "--file",
+ action="store", type="string", dest="filename")
+
+Now let's make up a fake command line and ask :mod:`optparse` to parse it::
+
+ args = ["-f", "foo.txt"]
+ (options, args) = parser.parse_args(args)
+
+When :mod:`optparse` sees the option string ``"-f"``, it consumes the next
+argument, ``"foo.txt"``, and stores it in ``options.filename``. So, after this
+call to :meth:`parse_args`, ``options.filename`` is ``"foo.txt"``.
+
+Some other option types supported by :mod:`optparse` are ``int`` and ``float``.
+Here's an option that expects an integer argument::
+
+ parser.add_option("-n", type="int", dest="num")
+
+Note that this option has no long option string, which is perfectly acceptable.
+Also, there's no explicit action, since the default is ``store``.
+
+Let's parse another fake command-line. This time, we'll jam the option argument
+right up against the option: since ``"-n42"`` (one argument) is equivalent to
+``"-n 42"`` (two arguments), the code ::
+
+ (options, args) = parser.parse_args(["-n42"])
+ print options.num
+
+will print ``"42"``.
+
+If you don't specify a type, :mod:`optparse` assumes ``string``. Combined with
+the fact that the default action is ``store``, that means our first example can
+be a lot shorter::
+
+ parser.add_option("-f", "--file", dest="filename")
+
+If you don't supply a destination, :mod:`optparse` figures out a sensible
+default from the option strings: if the first long option string is
+``"--foo-bar"``, then the default destination is ``foo_bar``. If there are no
+long option strings, :mod:`optparse` looks at the first short option string: the
+default destination for ``"-f"`` is ``f``.
+
+:mod:`optparse` also includes built-in ``long`` and ``complex`` types. Adding
+types is covered in section :ref:`optparse-extending-optparse`.
+
+
+.. _optparse-handling-boolean-options:
+
+Handling boolean (flag) options
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Flag options---set a variable to true or false when a particular option is seen
+---are quite common. :mod:`optparse` supports them with two separate actions,
+``store_true`` and ``store_false``. For example, you might have a ``verbose``
+flag that is turned on with ``"-v"`` and off with ``"-q"``::
+
+ parser.add_option("-v", action="store_true", dest="verbose")
+ parser.add_option("-q", action="store_false", dest="verbose")
+
+Here we have two different options with the same destination, which is perfectly
+OK. (It just means you have to be a bit careful when setting default values---
+see below.)
+
+When :mod:`optparse` encounters ``"-v"`` on the command line, it sets
+``options.verbose`` to ``True``; when it encounters ``"-q"``,
+``options.verbose`` is set to ``False``.
+
+
+.. _optparse-other-actions:
+
+Other actions
+^^^^^^^^^^^^^
+
+Some other actions supported by :mod:`optparse` are:
+
+``store_const``
+ store a constant value
+
+``append``
+ append this option's argument to a list
+
+``count``
+ increment a counter by one
+
+``callback``
+ call a specified function
+
+These are covered in section :ref:`optparse-reference-guide`, Reference Guide
+and section :ref:`optparse-option-callbacks`.
+
+
+.. _optparse-default-values:
+
+Default values
+^^^^^^^^^^^^^^
+
+All of the above examples involve setting some variable (the "destination") when
+certain command-line options are seen. What happens if those options are never
+seen? Since we didn't supply any defaults, they are all set to ``None``. This
+is usually fine, but sometimes you want more control. :mod:`optparse` lets you
+supply a default value for each destination, which is assigned before the
+command line is parsed.
+
+First, consider the verbose/quiet example. If we want :mod:`optparse` to set
+``verbose`` to ``True`` unless ``"-q"`` is seen, then we can do this::
+
+ parser.add_option("-v", action="store_true", dest="verbose", default=True)
+ parser.add_option("-q", action="store_false", dest="verbose")
+
+Since default values apply to the *destination* rather than to any particular
+option, and these two options happen to have the same destination, this is
+exactly equivalent::
+
+ parser.add_option("-v", action="store_true", dest="verbose")
+ parser.add_option("-q", action="store_false", dest="verbose", default=True)
+
+Consider this::
+
+ parser.add_option("-v", action="store_true", dest="verbose", default=False)
+ parser.add_option("-q", action="store_false", dest="verbose", default=True)
+
+Again, the default value for ``verbose`` will be ``True``: the last default
+value supplied for any particular destination is the one that counts.
+
+A clearer way to specify default values is the :meth:`set_defaults` method of
+OptionParser, which you can call at any time before calling :meth:`parse_args`::
+
+ parser.set_defaults(verbose=True)
+ parser.add_option(...)
+ (options, args) = parser.parse_args()
+
+As before, the last value specified for a given option destination is the one
+that counts. For clarity, try to use one method or the other of setting default
+values, not both.
+
+
+.. _optparse-generating-help:
+
+Generating help
+^^^^^^^^^^^^^^^
+
+:mod:`optparse`'s ability to generate help and usage text automatically is
+useful for creating user-friendly command-line interfaces. All you have to do
+is supply a :attr:`help` value for each option, and optionally a short usage
+message for your whole program. Here's an OptionParser populated with
+user-friendly (documented) options::
+
+ usage = "usage: %prog [options] arg1 arg2"
+ parser = OptionParser(usage=usage)
+ parser.add_option("-v", "--verbose",
+ action="store_true", dest="verbose", default=True,
+ help="make lots of noise [default]")
+ parser.add_option("-q", "--quiet",
+ action="store_false", dest="verbose",
+ help="be vewwy quiet (I'm hunting wabbits)")
+ parser.add_option("-f", "--filename",
+ metavar="FILE", help="write output to FILE"),
+ parser.add_option("-m", "--mode",
+ default="intermediate",
+ help="interaction mode: novice, intermediate, "
+ "or expert [default: %default]")
+
+If :mod:`optparse` encounters either ``"-h"`` or ``"--help"`` on the
+command-line, or if you just call :meth:`parser.print_help`, it prints the
+following to standard output::
+
+ usage: <yourscript> [options] arg1 arg2
+
+ options:
+ -h, --help show this help message and exit
+ -v, --verbose make lots of noise [default]
+ -q, --quiet be vewwy quiet (I'm hunting wabbits)
+ -f FILE, --filename=FILE
+ write output to FILE
+ -m MODE, --mode=MODE interaction mode: novice, intermediate, or
+ expert [default: intermediate]
+
+(If the help output is triggered by a help option, :mod:`optparse` exits after
+printing the help text.)
+
+There's a lot going on here to help :mod:`optparse` generate the best possible
+help message:
+
+* the script defines its own usage message::
+
+ usage = "usage: %prog [options] arg1 arg2"
+
+ :mod:`optparse` expands ``"%prog"`` in the usage string to the name of the
+ current program, i.e. ``os.path.basename(sys.argv[0])``. The expanded string is
+ then printed before the detailed option help.
+
+ If you don't supply a usage string, :mod:`optparse` uses a bland but sensible
+ default: ``"usage: %prog [options]"``, which is fine if your script doesn't take
+ any positional arguments.
+
+* every option defines a help string, and doesn't worry about line-wrapping---
+ :mod:`optparse` takes care of wrapping lines and making the help output look
+ good.
+
+* options that take a value indicate this fact in their automatically-generated
+ help message, e.g. for the "mode" option::
+
+ -m MODE, --mode=MODE
+
+ Here, "MODE" is called the meta-variable: it stands for the argument that the
+ user is expected to supply to :option:`-m`/:option:`--mode`. By default,
+ :mod:`optparse` converts the destination variable name to uppercase and uses
+ that for the meta-variable. Sometimes, that's not what you want---for example,
+ the :option:`--filename` option explicitly sets ``metavar="FILE"``, resulting in
+ this automatically-generated option description::
+
+ -f FILE, --filename=FILE
+
+ This is important for more than just saving space, though: the manually written
+ help text uses the meta-variable "FILE" to clue the user in that there's a
+ connection between the semi-formal syntax "-f FILE" and the informal semantic
+ description "write output to FILE". This is a simple but effective way to make
+ your help text a lot clearer and more useful for end users.
+
+* options that have a default value can include ``%default`` in the help
+ string---\ :mod:`optparse` will replace it with :func:`str` of the option's
+ default value. If an option has no default value (or the default value is
+ ``None``), ``%default`` expands to ``none``.
+
+
+.. _optparse-printing-version-string:
+
+Printing a version string
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Similar to the brief usage string, :mod:`optparse` can also print a version
+string for your program. You have to supply the string as the ``version``
+argument to OptionParser::
+
+ parser = OptionParser(usage="%prog [-f] [-q]", version="%prog 1.0")
+
+``"%prog"`` is expanded just like it is in ``usage``. Apart from that,
+``version`` can contain anything you like. When you supply it, :mod:`optparse`
+automatically adds a ``"--version"`` option to your parser. If it encounters
+this option on the command line, it expands your ``version`` string (by
+replacing ``"%prog"``), prints it to stdout, and exits.
+
+For example, if your script is called ``/usr/bin/foo``::
+
+ $ /usr/bin/foo --version
+ foo 1.0
+
+
+.. _optparse-how-optparse-handles-errors:
+
+How :mod:`optparse` handles errors
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+There are two broad classes of errors that :mod:`optparse` has to worry about:
+programmer errors and user errors. Programmer errors are usually erroneous
+calls to ``parser.add_option()``, e.g. invalid option strings, unknown option
+attributes, missing option attributes, etc. These are dealt with in the usual
+way: raise an exception (either ``optparse.OptionError`` or ``TypeError``) and
+let the program crash.
+
+Handling user errors is much more important, since they are guaranteed to happen
+no matter how stable your code is. :mod:`optparse` can automatically detect
+some user errors, such as bad option arguments (passing ``"-n 4x"`` where
+:option:`-n` takes an integer argument), missing arguments (``"-n"`` at the end
+of the command line, where :option:`-n` takes an argument of any type). Also,
+you can call ``parser.error()`` to signal an application-defined error
+condition::
+
+ (options, args) = parser.parse_args()
+ [...]
+ if options.a and options.b:
+ parser.error("options -a and -b are mutually exclusive")
+
+In either case, :mod:`optparse` handles the error the same way: it prints the
+program's usage message and an error message to standard error and exits with
+error status 2.
+
+Consider the first example above, where the user passes ``"4x"`` to an option
+that takes an integer::
+
+ $ /usr/bin/foo -n 4x
+ usage: foo [options]
+
+ foo: error: option -n: invalid integer value: '4x'
+
+Or, where the user fails to pass a value at all::
+
+ $ /usr/bin/foo -n
+ usage: foo [options]
+
+ foo: error: -n option requires an argument
+
+:mod:`optparse`\ -generated error messages take care always to mention the
+option involved in the error; be sure to do the same when calling
+``parser.error()`` from your application code.
+
+If :mod:`optparse`'s default error-handling behaviour does not suite your needs,
+you'll need to subclass OptionParser and override ``exit()`` and/or
+:meth:`error`.
+
+
+.. _optparse-putting-it-all-together:
+
+Putting it all together
+^^^^^^^^^^^^^^^^^^^^^^^
+
+Here's what :mod:`optparse`\ -based scripts usually look like::
+
+ from optparse import OptionParser
+ [...]
+ def main():
+ usage = "usage: %prog [options] arg"
+ parser = OptionParser(usage)
+ parser.add_option("-f", "--file", dest="filename",
+ help="read data from FILENAME")
+ parser.add_option("-v", "--verbose",
+ action="store_true", dest="verbose")
+ parser.add_option("-q", "--quiet",
+ action="store_false", dest="verbose")
+ [...]
+ (options, args) = parser.parse_args()
+ if len(args) != 1:
+ parser.error("incorrect number of arguments")
+ if options.verbose:
+ print "reading %s..." % options.filename
+ [...]
+
+ if __name__ == "__main__":
+ main()
+
+.. % $Id: tutorial.txt 515 2006-06-10 15:37:45Z gward $
+
+
+.. _optparse-reference-guide:
+
+Reference Guide
+---------------
+
+
+.. _optparse-creating-parser:
+
+Creating the parser
+^^^^^^^^^^^^^^^^^^^
+
+The first step in using :mod:`optparse` is to create an OptionParser instance::
+
+ parser = OptionParser(...)
+
+The OptionParser constructor has no required arguments, but a number of optional
+keyword arguments. You should always pass them as keyword arguments, i.e. do
+not rely on the order in which the arguments are declared.
+
+ ``usage`` (default: ``"%prog [options]"``)
+ The usage summary to print when your program is run incorrectly or with a help
+ option. When :mod:`optparse` prints the usage string, it expands ``%prog`` to
+ ``os.path.basename(sys.argv[0])`` (or to ``prog`` if you passed that keyword
+ argument). To suppress a usage message, pass the special value
+ ``optparse.SUPPRESS_USAGE``.
+
+ ``option_list`` (default: ``[]``)
+ A list of Option objects to populate the parser with. The options in
+ ``option_list`` are added after any options in ``standard_option_list`` (a class
+ attribute that may be set by OptionParser subclasses), but before any version or
+ help options. Deprecated; use :meth:`add_option` after creating the parser
+ instead.
+
+ ``option_class`` (default: optparse.Option)
+ Class to use when adding options to the parser in :meth:`add_option`.
+
+ ``version`` (default: ``None``)
+ A version string to print when the user supplies a version option. If you supply
+ a true value for ``version``, :mod:`optparse` automatically adds a version
+ option with the single option string ``"--version"``. The substring ``"%prog"``
+ is expanded the same as for ``usage``.
+
+ ``conflict_handler`` (default: ``"error"``)
+ Specifies what to do when options with conflicting option strings are added to
+ the parser; see section :ref:`optparse-conflicts-between-options`.
+
+ ``description`` (default: ``None``)
+ A paragraph of text giving a brief overview of your program. :mod:`optparse`
+ reformats this paragraph to fit the current terminal width and prints it when
+ the user requests help (after ``usage``, but before the list of options).
+
+ ``formatter`` (default: a new IndentedHelpFormatter)
+ An instance of optparse.HelpFormatter that will be used for printing help text.
+ :mod:`optparse` provides two concrete classes for this purpose:
+ IndentedHelpFormatter and TitledHelpFormatter.
+
+ ``add_help_option`` (default: ``True``)
+ If true, :mod:`optparse` will add a help option (with option strings ``"-h"``
+ and ``"--help"``) to the parser.
+
+ ``prog``
+ The string to use when expanding ``"%prog"`` in ``usage`` and ``version``
+ instead of ``os.path.basename(sys.argv[0])``.
+
+
+
+.. _optparse-populating-parser:
+
+Populating the parser
+^^^^^^^^^^^^^^^^^^^^^
+
+There are several ways to populate the parser with options. The preferred way
+is by using ``OptionParser.add_option()``, as shown in section
+:ref:`optparse-tutorial`. :meth:`add_option` can be called in one of two ways:
+
+* pass it an Option instance (as returned by :func:`make_option`)
+
+* pass it any combination of positional and keyword arguments that are
+ acceptable to :func:`make_option` (i.e., to the Option constructor), and it will
+ create the Option instance for you
+
+The other alternative is to pass a list of pre-constructed Option instances to
+the OptionParser constructor, as in::
+
+ option_list = [
+ make_option("-f", "--filename",
+ action="store", type="string", dest="filename"),
+ make_option("-q", "--quiet",
+ action="store_false", dest="verbose"),
+ ]
+ parser = OptionParser(option_list=option_list)
+
+(:func:`make_option` is a factory function for creating Option instances;
+currently it is an alias for the Option constructor. A future version of
+:mod:`optparse` may split Option into several classes, and :func:`make_option`
+will pick the right class to instantiate. Do not instantiate Option directly.)
+
+
+.. _optparse-defining-options:
+
+Defining options
+^^^^^^^^^^^^^^^^
+
+Each Option instance represents a set of synonymous command-line option strings,
+e.g. :option:`-f` and :option:`--file`. You can specify any number of short or
+long option strings, but you must specify at least one overall option string.
+
+The canonical way to create an Option instance is with the :meth:`add_option`
+method of :class:`OptionParser`::
+
+ parser.add_option(opt_str[, ...], attr=value, ...)
+
+To define an option with only a short option string::
+
+ parser.add_option("-f", attr=value, ...)
+
+And to define an option with only a long option string::
+
+ parser.add_option("--foo", attr=value, ...)
+
+The keyword arguments define attributes of the new Option object. The most
+important option attribute is :attr:`action`, and it largely determines which
+other attributes are relevant or required. If you pass irrelevant option
+attributes, or fail to pass required ones, :mod:`optparse` raises an OptionError
+exception explaining your mistake.
+
+An options's *action* determines what :mod:`optparse` does when it encounters
+this option on the command-line. The standard option actions hard-coded into
+:mod:`optparse` are:
+
+``store``
+ store this option's argument (default)
+
+``store_const``
+ store a constant value
+
+``store_true``
+ store a true value
+
+``store_false``
+ store a false value
+
+``append``
+ append this option's argument to a list
+
+``append_const``
+ append a constant value to a list
+
+``count``
+ increment a counter by one
+
+``callback``
+ call a specified function
+
+:attr:`help`
+ print a usage message including all options and the documentation for them
+
+(If you don't supply an action, the default is ``store``. For this action, you
+may also supply :attr:`type` and :attr:`dest` option attributes; see below.)
+
+As you can see, most actions involve storing or updating a value somewhere.
+:mod:`optparse` always creates a special object for this, conventionally called
+``options`` (it happens to be an instance of ``optparse.Values``). Option
+arguments (and various other values) are stored as attributes of this object,
+according to the :attr:`dest` (destination) option attribute.
+
+For example, when you call ::
+
+ parser.parse_args()
+
+one of the first things :mod:`optparse` does is create the ``options`` object::
+
+ options = Values()
+
+If one of the options in this parser is defined with ::
+
+ parser.add_option("-f", "--file", action="store", type="string", dest="filename")
+
+and the command-line being parsed includes any of the following::
+
+ -ffoo
+ -f foo
+ --file=foo
+ --file foo
+
+then :mod:`optparse`, on seeing this option, will do the equivalent of ::
+
+ options.filename = "foo"
+
+The :attr:`type` and :attr:`dest` option attributes are almost as important as
+:attr:`action`, but :attr:`action` is the only one that makes sense for *all*
+options.
+
+
+.. _optparse-standard-option-actions:
+
+Standard option actions
+^^^^^^^^^^^^^^^^^^^^^^^
+
+The various option actions all have slightly different requirements and effects.
+Most actions have several relevant option attributes which you may specify to
+guide :mod:`optparse`'s behaviour; a few have required attributes, which you
+must specify for any option using that action.
+
+* ``store`` [relevant: :attr:`type`, :attr:`dest`, ``nargs``, ``choices``]
+
+ The option must be followed by an argument, which is converted to a value
+ according to :attr:`type` and stored in :attr:`dest`. If ``nargs`` > 1,
+ multiple arguments will be consumed from the command line; all will be converted
+ according to :attr:`type` and stored to :attr:`dest` as a tuple. See the
+ "Option types" section below.
+
+ If ``choices`` is supplied (a list or tuple of strings), the type defaults to
+ ``choice``.
+
+ If :attr:`type` is not supplied, it defaults to ``string``.
+
+ If :attr:`dest` is not supplied, :mod:`optparse` derives a destination from the
+ first long option string (e.g., ``"--foo-bar"`` implies ``foo_bar``). If there
+ are no long option strings, :mod:`optparse` derives a destination from the first
+ short option string (e.g., ``"-f"`` implies ``f``).
+
+ Example::
+
+ parser.add_option("-f")
+ parser.add_option("-p", type="float", nargs=3, dest="point")
+
+ As it parses the command line ::
+
+ -f foo.txt -p 1 -3.5 4 -fbar.txt
+
+ :mod:`optparse` will set ::
+
+ options.f = "foo.txt"
+ options.point = (1.0, -3.5, 4.0)
+ options.f = "bar.txt"
+
+* ``store_const`` [required: ``const``; relevant: :attr:`dest`]
+
+ The value ``const`` is stored in :attr:`dest`.
+
+ Example::
+
+ parser.add_option("-q", "--quiet",
+ action="store_const", const=0, dest="verbose")
+ parser.add_option("-v", "--verbose",
+ action="store_const", const=1, dest="verbose")
+ parser.add_option("--noisy",
+ action="store_const", const=2, dest="verbose")
+
+ If ``"--noisy"`` is seen, :mod:`optparse` will set ::
+
+ options.verbose = 2
+
+* ``store_true`` [relevant: :attr:`dest`]
+
+ A special case of ``store_const`` that stores a true value to :attr:`dest`.
+
+* ``store_false`` [relevant: :attr:`dest`]
+
+ Like ``store_true``, but stores a false value.
+
+ Example::
+
+ parser.add_option("--clobber", action="store_true", dest="clobber")
+ parser.add_option("--no-clobber", action="store_false", dest="clobber")
+
+* ``append`` [relevant: :attr:`type`, :attr:`dest`, ``nargs``, ``choices``]
+
+ The option must be followed by an argument, which is appended to the list in
+ :attr:`dest`. If no default value for :attr:`dest` is supplied, an empty list
+ is automatically created when :mod:`optparse` first encounters this option on
+ the command-line. If ``nargs`` > 1, multiple arguments are consumed, and a
+ tuple of length ``nargs`` is appended to :attr:`dest`.
+
+ The defaults for :attr:`type` and :attr:`dest` are the same as for the ``store``
+ action.
+
+ Example::
+
+ parser.add_option("-t", "--tracks", action="append", type="int")
+
+ If ``"-t3"`` is seen on the command-line, :mod:`optparse` does the equivalent
+ of::
+
+ options.tracks = []
+ options.tracks.append(int("3"))
+
+ If, a little later on, ``"--tracks=4"`` is seen, it does::
+
+ options.tracks.append(int("4"))
+
+* ``append_const`` [required: ``const``; relevant: :attr:`dest`]
+
+ Like ``store_const``, but the value ``const`` is appended to :attr:`dest`; as
+ with ``append``, :attr:`dest` defaults to ``None``, and an an empty list is
+ automatically created the first time the option is encountered.
+
+* ``count`` [relevant: :attr:`dest`]
+
+ Increment the integer stored at :attr:`dest`. If no default value is supplied,
+ :attr:`dest` is set to zero before being incremented the first time.
+
+ Example::
+
+ parser.add_option("-v", action="count", dest="verbosity")
+
+ The first time ``"-v"`` is seen on the command line, :mod:`optparse` does the
+ equivalent of::
+
+ options.verbosity = 0
+ options.verbosity += 1
+
+ Every subsequent occurrence of ``"-v"`` results in ::
+
+ options.verbosity += 1
+
+* ``callback`` [required: ``callback``; relevant: :attr:`type`, ``nargs``,
+ ``callback_args``, ``callback_kwargs``]
+
+ Call the function specified by ``callback``, which is called as ::
+
+ func(option, opt_str, value, parser, *args, **kwargs)
+
+ See section :ref:`optparse-option-callbacks` for more detail.
+
+* :attr:`help`
+
+ Prints a complete help message for all the options in the current option parser.
+ The help message is constructed from the ``usage`` string passed to
+ OptionParser's constructor and the :attr:`help` string passed to every option.
+
+ If no :attr:`help` string is supplied for an option, it will still be listed in
+ the help message. To omit an option entirely, use the special value
+ ``optparse.SUPPRESS_HELP``.
+
+ :mod:`optparse` automatically adds a :attr:`help` option to all OptionParsers,
+ so you do not normally need to create one.
+
+ Example::
+
+ from optparse import OptionParser, SUPPRESS_HELP
+
+ parser = OptionParser()
+ parser.add_option("-h", "--help", action="help"),
+ parser.add_option("-v", action="store_true", dest="verbose",
+ help="Be moderately verbose")
+ parser.add_option("--file", dest="filename",
+ help="Input file to read data from"),
+ parser.add_option("--secret", help=SUPPRESS_HELP)
+
+ If :mod:`optparse` sees either ``"-h"`` or ``"--help"`` on the command line, it
+ will print something like the following help message to stdout (assuming
+ ``sys.argv[0]`` is ``"foo.py"``)::
+
+ usage: foo.py [options]
+
+ options:
+ -h, --help Show this help message and exit
+ -v Be moderately verbose
+ --file=FILENAME Input file to read data from
+
+ After printing the help message, :mod:`optparse` terminates your process with
+ ``sys.exit(0)``.
+
+* ``version``
+
+ Prints the version number supplied to the OptionParser to stdout and exits. The
+ version number is actually formatted and printed by the ``print_version()``
+ method of OptionParser. Generally only relevant if the ``version`` argument is
+ supplied to the OptionParser constructor. As with :attr:`help` options, you
+ will rarely create ``version`` options, since :mod:`optparse` automatically adds
+ them when needed.
+
+
+.. _optparse-option-attributes:
+
+Option attributes
+^^^^^^^^^^^^^^^^^
+
+The following option attributes may be passed as keyword arguments to
+``parser.add_option()``. If you pass an option attribute that is not relevant
+to a particular option, or fail to pass a required option attribute,
+:mod:`optparse` raises OptionError.
+
+* :attr:`action` (default: ``"store"``)
+
+ Determines :mod:`optparse`'s behaviour when this option is seen on the command
+ line; the available options are documented above.
+
+* :attr:`type` (default: ``"string"``)
+
+ The argument type expected by this option (e.g., ``"string"`` or ``"int"``); the
+ available option types are documented below.
+
+* :attr:`dest` (default: derived from option strings)
+
+ If the option's action implies writing or modifying a value somewhere, this
+ tells :mod:`optparse` where to write it: :attr:`dest` names an attribute of the
+ ``options`` object that :mod:`optparse` builds as it parses the command line.
+
+* ``default`` (deprecated)
+
+ The value to use for this option's destination if the option is not seen on the
+ command line. Deprecated; use ``parser.set_defaults()`` instead.
+
+* ``nargs`` (default: 1)
+
+ How many arguments of type :attr:`type` should be consumed when this option is
+ seen. If > 1, :mod:`optparse` will store a tuple of values to :attr:`dest`.
+
+* ``const``
+
+ For actions that store a constant value, the constant value to store.
+
+* ``choices``
+
+ For options of type ``"choice"``, the list of strings the user may choose from.
+
+* ``callback``
+
+ For options with action ``"callback"``, the callable to call when this option
+ is seen. See section :ref:`optparse-option-callbacks` for detail on the
+ arguments passed to ``callable``.
+
+* ``callback_args``, ``callback_kwargs``
+
+ Additional positional and keyword arguments to pass to ``callback`` after the
+ four standard callback arguments.
+
+* :attr:`help`
+
+ Help text to print for this option when listing all available options after the
+ user supplies a :attr:`help` option (such as ``"--help"``). If no help text is
+ supplied, the option will be listed without help text. To hide this option, use
+ the special value ``SUPPRESS_HELP``.
+
+* ``metavar`` (default: derived from option strings)
+
+ Stand-in for the option argument(s) to use when printing help text. See section
+ :ref:`optparse-tutorial` for an example.
+
+
+.. _optparse-standard-option-types:
+
+Standard option types
+^^^^^^^^^^^^^^^^^^^^^
+
+:mod:`optparse` has six built-in option types: ``string``, ``int``, ``long``,
+``choice``, ``float`` and ``complex``. If you need to add new option types, see
+section :ref:`optparse-extending-optparse`.
+
+Arguments to string options are not checked or converted in any way: the text on
+the command line is stored in the destination (or passed to the callback) as-is.
+
+Integer arguments (type ``int`` or ``long``) are parsed as follows:
+
+* if the number starts with ``0x``, it is parsed as a hexadecimal number
+
+* if the number starts with ``0``, it is parsed as an octal number
+
+* if the number starts with ``0b``, is is parsed as a binary number
+
+* otherwise, the number is parsed as a decimal number
+
+
+The conversion is done by calling either ``int()`` or ``long()`` with the
+appropriate base (2, 8, 10, or 16). If this fails, so will :mod:`optparse`,
+although with a more useful error message.
+
+``float`` and ``complex`` option arguments are converted directly with
+``float()`` and ``complex()``, with similar error-handling.
+
+``choice`` options are a subtype of ``string`` options. The ``choices`` option
+attribute (a sequence of strings) defines the set of allowed option arguments.
+``optparse.check_choice()`` compares user-supplied option arguments against this
+master list and raises OptionValueError if an invalid string is given.
+
+
+.. _optparse-parsing-arguments:
+
+Parsing arguments
+^^^^^^^^^^^^^^^^^
+
+The whole point of creating and populating an OptionParser is to call its
+:meth:`parse_args` method::
+
+ (options, args) = parser.parse_args(args=None, values=None)
+
+where the input parameters are
+
+``args``
+ the list of arguments to process (default: ``sys.argv[1:]``)
+
+``values``
+ object to store option arguments in (default: a new instance of optparse.Values)
+
+and the return values are
+
+``options``
+ the same object that was passed in as ``options``, or the optparse.Values
+ instance created by :mod:`optparse`
+
+``args``
+ the leftover positional arguments after all options have been processed
+
+The most common usage is to supply neither keyword argument. If you supply
+``options``, it will be modified with repeated ``setattr()`` calls (roughly one
+for every option argument stored to an option destination) and returned by
+:meth:`parse_args`.
+
+If :meth:`parse_args` encounters any errors in the argument list, it calls the
+OptionParser's :meth:`error` method with an appropriate end-user error message.
+This ultimately terminates your process with an exit status of 2 (the
+traditional Unix exit status for command-line errors).
+
+
+.. _optparse-querying-manipulating-option-parser:
+
+Querying and manipulating your option parser
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sometimes, it's useful to poke around your option parser and see what's there.
+OptionParser provides a couple of methods to help you out:
+
+``has_option(opt_str)``
+ Return true if the OptionParser has an option with option string ``opt_str``
+ (e.g., ``"-q"`` or ``"--verbose"``).
+
+``get_option(opt_str)``
+ Returns the Option instance with the option string ``opt_str``, or ``None`` if
+ no options have that option string.
+
+``remove_option(opt_str)``
+ If the OptionParser has an option corresponding to ``opt_str``, that option is
+ removed. If that option provided any other option strings, all of those option
+ strings become invalid. If ``opt_str`` does not occur in any option belonging to
+ this OptionParser, raises ValueError.
+
+
+.. _optparse-conflicts-between-options:
+
+Conflicts between options
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If you're not careful, it's easy to define options with conflicting option
+strings::
+
+ parser.add_option("-n", "--dry-run", ...)
+ [...]
+ parser.add_option("-n", "--noisy", ...)
+
+(This is particularly true if you've defined your own OptionParser subclass with
+some standard options.)
+
+Every time you add an option, :mod:`optparse` checks for conflicts with existing
+options. If it finds any, it invokes the current conflict-handling mechanism.
+You can set the conflict-handling mechanism either in the constructor::
+
+ parser = OptionParser(..., conflict_handler=handler)
+
+or with a separate call::
+
+ parser.set_conflict_handler(handler)
+
+The available conflict handlers are:
+
+ ``error`` (default)
+ assume option conflicts are a programming error and raise OptionConflictError
+
+ ``resolve``
+ resolve option conflicts intelligently (see below)
+
+
+As an example, let's define an OptionParser that resolves conflicts
+intelligently and add conflicting options to it::
+
+ parser = OptionParser(conflict_handler="resolve")
+ parser.add_option("-n", "--dry-run", ..., help="do no harm")
+ parser.add_option("-n", "--noisy", ..., help="be noisy")
+
+At this point, :mod:`optparse` detects that a previously-added option is already
+using the ``"-n"`` option string. Since ``conflict_handler`` is ``"resolve"``,
+it resolves the situation by removing ``"-n"`` from the earlier option's list of
+option strings. Now ``"--dry-run"`` is the only way for the user to activate
+that option. If the user asks for help, the help message will reflect that::
+
+ options:
+ --dry-run do no harm
+ [...]
+ -n, --noisy be noisy
+
+It's possible to whittle away the option strings for a previously-added option
+until there are none left, and the user has no way of invoking that option from
+the command-line. In that case, :mod:`optparse` removes that option completely,
+so it doesn't show up in help text or anywhere else. Carrying on with our
+existing OptionParser::
+
+ parser.add_option("--dry-run", ..., help="new dry-run option")
+
+At this point, the original :option:`-n/--dry-run` option is no longer
+accessible, so :mod:`optparse` removes it, leaving this help text::
+
+ options:
+ [...]
+ -n, --noisy be noisy
+ --dry-run new dry-run option
+
+
+.. _optparse-cleanup:
+
+Cleanup
+^^^^^^^
+
+OptionParser instances have several cyclic references. This should not be a
+problem for Python's garbage collector, but you may wish to break the cyclic
+references explicitly by calling ``destroy()`` on your OptionParser once you are
+done with it. This is particularly useful in long-running applications where
+large object graphs are reachable from your OptionParser.
+
+
+.. _optparse-other-methods:
+
+Other methods
+^^^^^^^^^^^^^
+
+OptionParser supports several other public methods:
+
+* ``set_usage(usage)``
+
+ Set the usage string according to the rules described above for the ``usage``
+ constructor keyword argument. Passing ``None`` sets the default usage string;
+ use ``SUPPRESS_USAGE`` to suppress a usage message.
+
+* ``enable_interspersed_args()``, ``disable_interspersed_args()``
+
+ Enable/disable positional arguments interspersed with options, similar to GNU
+ getopt (enabled by default). For example, if ``"-a"`` and ``"-b"`` are both
+ simple options that take no arguments, :mod:`optparse` normally accepts this
+ syntax::
+
+ prog -a arg1 -b arg2
+
+ and treats it as equivalent to ::
+
+ prog -a -b arg1 arg2
+
+ To disable this feature, call ``disable_interspersed_args()``. This restores
+ traditional Unix syntax, where option parsing stops with the first non-option
+ argument.
+
+* ``set_defaults(dest=value, ...)``
+
+ Set default values for several option destinations at once. Using
+ :meth:`set_defaults` is the preferred way to set default values for options,
+ since multiple options can share the same destination. For example, if several
+ "mode" options all set the same destination, any one of them can set the
+ default, and the last one wins::
+
+ parser.add_option("--advanced", action="store_const",
+ dest="mode", const="advanced",
+ default="novice") # overridden below
+ parser.add_option("--novice", action="store_const",
+ dest="mode", const="novice",
+ default="advanced") # overrides above setting
+
+ To avoid this confusion, use :meth:`set_defaults`::
+
+ parser.set_defaults(mode="advanced")
+ parser.add_option("--advanced", action="store_const",
+ dest="mode", const="advanced")
+ parser.add_option("--novice", action="store_const",
+ dest="mode", const="novice")
+
+.. % $Id: reference.txt 519 2006-06-11 14:39:11Z gward $
+
+
+.. _optparse-option-callbacks:
+
+Option Callbacks
+----------------
+
+When :mod:`optparse`'s built-in actions and types aren't quite enough for your
+needs, you have two choices: extend :mod:`optparse` or define a callback option.
+Extending :mod:`optparse` is more general, but overkill for a lot of simple
+cases. Quite often a simple callback is all you need.
+
+There are two steps to defining a callback option:
+
+* define the option itself using the ``callback`` action
+
+* write the callback; this is a function (or method) that takes at least four
+ arguments, as described below
+
+
+.. _optparse-defining-callback-option:
+
+Defining a callback option
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+As always, the easiest way to define a callback option is by using the
+``parser.add_option()`` method. Apart from :attr:`action`, the only option
+attribute you must specify is ``callback``, the function to call::
+
+ parser.add_option("-c", action="callback", callback=my_callback)
+
+``callback`` is a function (or other callable object), so you must have already
+defined ``my_callback()`` when you create this callback option. In this simple
+case, :mod:`optparse` doesn't even know if :option:`-c` takes any arguments,
+which usually means that the option takes no arguments---the mere presence of
+:option:`-c` on the command-line is all it needs to know. In some
+circumstances, though, you might want your callback to consume an arbitrary
+number of command-line arguments. This is where writing callbacks gets tricky;
+it's covered later in this section.
+
+:mod:`optparse` always passes four particular arguments to your callback, and it
+will only pass additional arguments if you specify them via ``callback_args``
+and ``callback_kwargs``. Thus, the minimal callback function signature is::
+
+ def my_callback(option, opt, value, parser):
+
+The four arguments to a callback are described below.
+
+There are several other option attributes that you can supply when you define a
+callback option:
+
+:attr:`type`
+ has its usual meaning: as with the ``store`` or ``append`` actions, it instructs
+ :mod:`optparse` to consume one argument and convert it to :attr:`type`. Rather
+ than storing the converted value(s) anywhere, though, :mod:`optparse` passes it
+ to your callback function.
+
+``nargs``
+ also has its usual meaning: if it is supplied and > 1, :mod:`optparse` will
+ consume ``nargs`` arguments, each of which must be convertible to :attr:`type`.
+ It then passes a tuple of converted values to your callback.
+
+``callback_args``
+ a tuple of extra positional arguments to pass to the callback
+
+``callback_kwargs``
+ a dictionary of extra keyword arguments to pass to the callback
+
+
+.. _optparse-how-callbacks-called:
+
+How callbacks are called
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+All callbacks are called as follows::
+
+ func(option, opt_str, value, parser, *args, **kwargs)
+
+where
+
+``option``
+ is the Option instance that's calling the callback
+
+``opt_str``
+ is the option string seen on the command-line that's triggering the callback.
+ (If an abbreviated long option was used, ``opt_str`` will be the full, canonical
+ option string---e.g. if the user puts ``"--foo"`` on the command-line as an
+ abbreviation for ``"--foobar"``, then ``opt_str`` will be ``"--foobar"``.)
+
+``value``
+ is the argument to this option seen on the command-line. :mod:`optparse` will
+ only expect an argument if :attr:`type` is set; the type of ``value`` will be
+ the type implied by the option's type. If :attr:`type` for this option is
+ ``None`` (no argument expected), then ``value`` will be ``None``. If ``nargs``
+ > 1, ``value`` will be a tuple of values of the appropriate type.
+
+``parser``
+ is the OptionParser instance driving the whole thing, mainly useful because you
+ can access some other interesting data through its instance attributes:
+
+ ``parser.largs``
+ the current list of leftover arguments, ie. arguments that have been consumed
+ but are neither options nor option arguments. Feel free to modify
+ ``parser.largs``, e.g. by adding more arguments to it. (This list will become
+ ``args``, the second return value of :meth:`parse_args`.)
+
+ ``parser.rargs``
+ the current list of remaining arguments, ie. with ``opt_str`` and ``value`` (if
+ applicable) removed, and only the arguments following them still there. Feel
+ free to modify ``parser.rargs``, e.g. by consuming more arguments.
+
+ ``parser.values``
+ the object where option values are by default stored (an instance of
+ optparse.OptionValues). This lets callbacks use the same mechanism as the rest
+ of :mod:`optparse` for storing option values; you don't need to mess around with
+ globals or closures. You can also access or modify the value(s) of any options
+ already encountered on the command-line.
+
+``args``
+ is a tuple of arbitrary positional arguments supplied via the ``callback_args``
+ option attribute.
+
+``kwargs``
+ is a dictionary of arbitrary keyword arguments supplied via ``callback_kwargs``.
+
+
+.. _optparse-raising-errors-in-callback:
+
+Raising errors in a callback
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The callback function should raise OptionValueError if there are any problems
+with the option or its argument(s). :mod:`optparse` catches this and terminates
+the program, printing the error message you supply to stderr. Your message
+should be clear, concise, accurate, and mention the option at fault. Otherwise,
+the user will have a hard time figuring out what he did wrong.
+
+
+.. _optparse-callback-example-1:
+
+Callback example 1: trivial callback
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Here's an example of a callback option that takes no arguments, and simply
+records that the option was seen::
+
+ def record_foo_seen(option, opt_str, value, parser):
+ parser.saw_foo = True
+
+ parser.add_option("--foo", action="callback", callback=record_foo_seen)
+
+Of course, you could do that with the ``store_true`` action.
+
+
+.. _optparse-callback-example-2:
+
+Callback example 2: check option order
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Here's a slightly more interesting example: record the fact that ``"-a"`` is
+seen, but blow up if it comes after ``"-b"`` in the command-line. ::
+
+ def check_order(option, opt_str, value, parser):
+ if parser.values.b:
+ raise OptionValueError("can't use -a after -b")
+ parser.values.a = 1
+ [...]
+ parser.add_option("-a", action="callback", callback=check_order)
+ parser.add_option("-b", action="store_true", dest="b")
+
+
+.. _optparse-callback-example-3:
+
+Callback example 3: check option order (generalized)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If you want to re-use this callback for several similar options (set a flag, but
+blow up if ``"-b"`` has already been seen), it needs a bit of work: the error
+message and the flag that it sets must be generalized. ::
+
+ def check_order(option, opt_str, value, parser):
+ if parser.values.b:
+ raise OptionValueError("can't use %s after -b" % opt_str)
+ setattr(parser.values, option.dest, 1)
+ [...]
+ parser.add_option("-a", action="callback", callback=check_order, dest='a')
+ parser.add_option("-b", action="store_true", dest="b")
+ parser.add_option("-c", action="callback", callback=check_order, dest='c')
+
+
+.. _optparse-callback-example-4:
+
+Callback example 4: check arbitrary condition
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Of course, you could put any condition in there---you're not limited to checking
+the values of already-defined options. For example, if you have options that
+should not be called when the moon is full, all you have to do is this::
+
+ def check_moon(option, opt_str, value, parser):
+ if is_moon_full():
+ raise OptionValueError("%s option invalid when moon is full"
+ % opt_str)
+ setattr(parser.values, option.dest, 1)
+ [...]
+ parser.add_option("--foo",
+ action="callback", callback=check_moon, dest="foo")
+
+(The definition of ``is_moon_full()`` is left as an exercise for the reader.)
+
+
+.. _optparse-callback-example-5:
+
+Callback example 5: fixed arguments
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Things get slightly more interesting when you define callback options that take
+a fixed number of arguments. Specifying that a callback option takes arguments
+is similar to defining a ``store`` or ``append`` option: if you define
+:attr:`type`, then the option takes one argument that must be convertible to
+that type; if you further define ``nargs``, then the option takes ``nargs``
+arguments.
+
+Here's an example that just emulates the standard ``store`` action::
+
+ def store_value(option, opt_str, value, parser):
+ setattr(parser.values, option.dest, value)
+ [...]
+ parser.add_option("--foo",
+ action="callback", callback=store_value,
+ type="int", nargs=3, dest="foo")
+
+Note that :mod:`optparse` takes care of consuming 3 arguments and converting
+them to integers for you; all you have to do is store them. (Or whatever;
+obviously you don't need a callback for this example.)
+
+
+.. _optparse-callback-example-6:
+
+Callback example 6: variable arguments
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Things get hairy when you want an option to take a variable number of arguments.
+For this case, you must write a callback, as :mod:`optparse` doesn't provide any
+built-in capabilities for it. And you have to deal with certain intricacies of
+conventional Unix command-line parsing that :mod:`optparse` normally handles for
+you. In particular, callbacks should implement the conventional rules for bare
+``"--"`` and ``"-"`` arguments:
+
+* either ``"--"`` or ``"-"`` can be option arguments
+
+* bare ``"--"`` (if not the argument to some option): halt command-line
+ processing and discard the ``"--"``
+
+* bare ``"-"`` (if not the argument to some option): halt command-line
+ processing but keep the ``"-"`` (append it to ``parser.largs``)
+
+If you want an option that takes a variable number of arguments, there are
+several subtle, tricky issues to worry about. The exact implementation you
+choose will be based on which trade-offs you're willing to make for your
+application (which is why :mod:`optparse` doesn't support this sort of thing
+directly).
+
+Nevertheless, here's a stab at a callback for an option with variable
+arguments::
+
+ def vararg_callback(option, opt_str, value, parser):
+ assert value is None
+ done = 0
+ value = []
+ rargs = parser.rargs
+ while rargs:
+ arg = rargs[0]
+
+ # Stop if we hit an arg like "--foo", "-a", "-fx", "--file=f",
+ # etc. Note that this also stops on "-3" or "-3.0", so if
+ # your option takes numeric values, you will need to handle
+ # this.
+ if ((arg[:2] == "--" and len(arg) > 2) or
+ (arg[:1] == "-" and len(arg) > 1 and arg[1] != "-")):
+ break
+ else:
+ value.append(arg)
+ del rargs[0]
+
+ setattr(parser.values, option.dest, value)
+
+ [...]
+ parser.add_option("-c", "--callback",
+ action="callback", callback=varargs)
+
+The main weakness with this particular implementation is that negative numbers
+in the arguments following ``"-c"`` will be interpreted as further options
+(probably causing an error), rather than as arguments to ``"-c"``. Fixing this
+is left as an exercise for the reader.
+
+.. % $Id: callbacks.txt 415 2004-09-30 02:26:17Z greg $
+
+
+.. _optparse-extending-optparse:
+
+Extending :mod:`optparse`
+-------------------------
+
+Since the two major controlling factors in how :mod:`optparse` interprets
+command-line options are the action and type of each option, the most likely
+direction of extension is to add new actions and new types.
+
+
+.. _optparse-adding-new-types:
+
+Adding new types
+^^^^^^^^^^^^^^^^
+
+To add new types, you need to define your own subclass of :mod:`optparse`'s
+Option class. This class has a couple of attributes that define
+:mod:`optparse`'s types: :attr:`TYPES` and :attr:`TYPE_CHECKER`.
+
+:attr:`TYPES` is a tuple of type names; in your subclass, simply define a new
+tuple :attr:`TYPES` that builds on the standard one.
+
+:attr:`TYPE_CHECKER` is a dictionary mapping type names to type-checking
+functions. A type-checking function has the following signature::
+
+ def check_mytype(option, opt, value)
+
+where ``option`` is an :class:`Option` instance, ``opt`` is an option string
+(e.g., ``"-f"``), and ``value`` is the string from the command line that must be
+checked and converted to your desired type. ``check_mytype()`` should return an
+object of the hypothetical type ``mytype``. The value returned by a
+type-checking function will wind up in the OptionValues instance returned by
+:meth:`OptionParser.parse_args`, or be passed to a callback as the ``value``
+parameter.
+
+Your type-checking function should raise OptionValueError if it encounters any
+problems. OptionValueError takes a single string argument, which is passed
+as-is to OptionParser's :meth:`error` method, which in turn prepends the program
+name and the string ``"error:"`` and prints everything to stderr before
+terminating the process.
+
+Here's a silly example that demonstrates adding a ``complex`` option type to
+parse Python-style complex numbers on the command line. (This is even sillier
+than it used to be, because :mod:`optparse` 1.3 added built-in support for
+complex numbers, but never mind.)
+
+First, the necessary imports::
+
+ from copy import copy
+ from optparse import Option, OptionValueError
+
+You need to define your type-checker first, since it's referred to later (in the
+:attr:`TYPE_CHECKER` class attribute of your Option subclass)::
+
+ def check_complex(option, opt, value):
+ try:
+ return complex(value)
+ except ValueError:
+ raise OptionValueError(
+ "option %s: invalid complex value: %r" % (opt, value))
+
+Finally, the Option subclass::
+
+ class MyOption (Option):
+ TYPES = Option.TYPES + ("complex",)
+ TYPE_CHECKER = copy(Option.TYPE_CHECKER)
+ TYPE_CHECKER["complex"] = check_complex
+
+(If we didn't make a :func:`copy` of :attr:`Option.TYPE_CHECKER`, we would end
+up modifying the :attr:`TYPE_CHECKER` attribute of :mod:`optparse`'s Option
+class. This being Python, nothing stops you from doing that except good manners
+and common sense.)
+
+That's it! Now you can write a script that uses the new option type just like
+any other :mod:`optparse`\ -based script, except you have to instruct your
+OptionParser to use MyOption instead of Option::
+
+ parser = OptionParser(option_class=MyOption)
+ parser.add_option("-c", type="complex")
+
+Alternately, you can build your own option list and pass it to OptionParser; if
+you don't use :meth:`add_option` in the above way, you don't need to tell
+OptionParser which option class to use::
+
+ option_list = [MyOption("-c", action="store", type="complex", dest="c")]
+ parser = OptionParser(option_list=option_list)
+
+
+.. _optparse-adding-new-actions:
+
+Adding new actions
+^^^^^^^^^^^^^^^^^^
+
+Adding new actions is a bit trickier, because you have to understand that
+:mod:`optparse` has a couple of classifications for actions:
+
+"store" actions
+ actions that result in :mod:`optparse` storing a value to an attribute of the
+ current OptionValues instance; these options require a :attr:`dest` attribute to
+ be supplied to the Option constructor
+
+"typed" actions
+ actions that take a value from the command line and expect it to be of a certain
+ type; or rather, a string that can be converted to a certain type. These
+ options require a :attr:`type` attribute to the Option constructor.
+
+These are overlapping sets: some default "store" actions are ``store``,
+``store_const``, ``append``, and ``count``, while the default "typed" actions
+are ``store``, ``append``, and ``callback``.
+
+When you add an action, you need to categorize it by listing it in at least one
+of the following class attributes of Option (all are lists of strings):
+
+:attr:`ACTIONS`
+ all actions must be listed in ACTIONS
+
+:attr:`STORE_ACTIONS`
+ "store" actions are additionally listed here
+
+:attr:`TYPED_ACTIONS`
+ "typed" actions are additionally listed here
+
+``ALWAYS_TYPED_ACTIONS``
+ actions that always take a type (i.e. whose options always take a value) are
+ additionally listed here. The only effect of this is that :mod:`optparse`
+ assigns the default type, ``string``, to options with no explicit type whose
+ action is listed in ``ALWAYS_TYPED_ACTIONS``.
+
+In order to actually implement your new action, you must override Option's
+:meth:`take_action` method and add a case that recognizes your action.
+
+For example, let's add an ``extend`` action. This is similar to the standard
+``append`` action, but instead of taking a single value from the command-line
+and appending it to an existing list, ``extend`` will take multiple values in a
+single comma-delimited string, and extend an existing list with them. That is,
+if ``"--names"`` is an ``extend`` option of type ``string``, the command line
+::
+
+ --names=foo,bar --names blah --names ding,dong
+
+would result in a list ::
+
+ ["foo", "bar", "blah", "ding", "dong"]
+
+Again we define a subclass of Option::
+
+ class MyOption (Option):
+
+ ACTIONS = Option.ACTIONS + ("extend",)
+ STORE_ACTIONS = Option.STORE_ACTIONS + ("extend",)
+ TYPED_ACTIONS = Option.TYPED_ACTIONS + ("extend",)
+ ALWAYS_TYPED_ACTIONS = Option.ALWAYS_TYPED_ACTIONS + ("extend",)
+
+ def take_action(self, action, dest, opt, value, values, parser):
+ if action == "extend":
+ lvalue = value.split(",")
+ values.ensure_value(dest, []).extend(lvalue)
+ else:
+ Option.take_action(
+ self, action, dest, opt, value, values, parser)
+
+Features of note:
+
+* ``extend`` both expects a value on the command-line and stores that value
+ somewhere, so it goes in both :attr:`STORE_ACTIONS` and :attr:`TYPED_ACTIONS`
+
+* to ensure that :mod:`optparse` assigns the default type of ``string`` to
+ ``extend`` actions, we put the ``extend`` action in ``ALWAYS_TYPED_ACTIONS`` as
+ well
+
+* :meth:`MyOption.take_action` implements just this one new action, and passes
+ control back to :meth:`Option.take_action` for the standard :mod:`optparse`
+ actions
+
+* ``values`` is an instance of the optparse_parser.Values class, which
+ provides the very useful :meth:`ensure_value` method. :meth:`ensure_value` is
+ essentially :func:`getattr` with a safety valve; it is called as ::
+
+ values.ensure_value(attr, value)
+
+ If the ``attr`` attribute of ``values`` doesn't exist or is None, then
+ ensure_value() first sets it to ``value``, and then returns 'value. This is very
+ handy for actions like ``extend``, ``append``, and ``count``, all of which
+ accumulate data in a variable and expect that variable to be of a certain type
+ (a list for the first two, an integer for the latter). Using
+ :meth:`ensure_value` means that scripts using your action don't have to worry
+ about setting a default value for the option destinations in question; they can
+ just leave the default as None and :meth:`ensure_value` will take care of
+ getting it right when it's needed.
+
+.. % $Id: extending.txt 517 2006-06-10 16:18:11Z gward $
+
diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst
new file mode 100644
index 0000000000..291d15579f
--- /dev/null
+++ b/Doc/library/os.path.rst
@@ -0,0 +1,317 @@
+
+:mod:`os.path` --- Common pathname manipulations
+================================================
+
+.. module:: os.path
+ :synopsis: Operations on pathnames.
+
+
+.. index:: single: path; operations
+
+This module implements some useful functions on pathnames. To read or
+write files see :func:`open`, and for accessing the filesystem see the
+:mod:`os` module.
+
+.. warning::
+
+ On Windows, many of these functions do not properly support UNC pathnames.
+ :func:`splitunc` and :func:`ismount` do handle them correctly.
+
+
+.. function:: abspath(path)
+
+ Return a normalized absolutized version of the pathname *path*. On most
+ platforms, this is equivalent to ``normpath(join(os.getcwd(), path))``.
+
+ .. versionadded:: 1.5.2
+
+
+.. function:: basename(path)
+
+ Return the base name of pathname *path*. This is the second half of the pair
+ returned by ``split(path)``. Note that the result of this function is different
+ from the Unix :program:`basename` program; where :program:`basename` for
+ ``'/foo/bar/'`` returns ``'bar'``, the :func:`basename` function returns an
+ empty string (``''``).
+
+
+.. function:: commonprefix(list)
+
+ Return the longest path prefix (taken character-by-character) that is a prefix
+ of all paths in *list*. If *list* is empty, return the empty string (``''``).
+ Note that this may return invalid paths because it works a character at a time.
+
+
+.. function:: dirname(path)
+
+ Return the directory name of pathname *path*. This is the first half of the
+ pair returned by ``split(path)``.
+
+
+.. function:: exists(path)
+
+ Return ``True`` if *path* refers to an existing path. Returns ``False`` for
+ broken symbolic links. On some platforms, this function may return ``False`` if
+ permission is not granted to execute :func:`os.stat` on the requested file, even
+ if the *path* physically exists.
+
+
+.. function:: lexists(path)
+
+ Return ``True`` if *path* refers to an existing path. Returns ``True`` for
+ broken symbolic links. Equivalent to :func:`exists` on platforms lacking
+ :func:`os.lstat`.
+
+ .. versionadded:: 2.4
+
+
+.. function:: expanduser(path)
+
+ On Unix and Windows, return the argument with an initial component of ``~`` or
+ ``~user`` replaced by that *user*'s home directory.
+
+ .. index:: module: pwd
+
+ On Unix, an initial ``~`` is replaced by the environment variable :envvar:`HOME`
+ if it is set; otherwise the current user's home directory is looked up in the
+ password directory through the built-in module :mod:`pwd`. An initial ``~user``
+ is looked up directly in the password directory.
+
+ On Windows, :envvar:`HOME` and :envvar:`USERPROFILE` will be used if set,
+ otherwise a combination of :envvar:`HOMEPATH` and :envvar:`HOMEDRIVE` will be
+ used. An initial ``~user`` is handled by stripping the last directory component
+ from the created user path derived above.
+
+ If the expansion fails or if the path does not begin with a tilde, the path is
+ returned unchanged.
+
+
+.. function:: expandvars(path)
+
+ Return the argument with environment variables expanded. Substrings of the form
+ ``$name`` or ``${name}`` are replaced by the value of environment variable
+ *name*. Malformed variable names and references to non-existing variables are
+ left unchanged.
+
+ On Windows, ``%name%`` expansions are supported in addition to ``$name`` and
+ ``${name}``.
+
+
+.. function:: getatime(path)
+
+ Return the time of last access of *path*. The return value is a number giving
+ the number of seconds since the epoch (see the :mod:`time` module). Raise
+ :exc:`os.error` if the file does not exist or is inaccessible.
+
+ .. versionadded:: 1.5.2
+
+ .. versionchanged:: 2.3
+ If :func:`os.stat_float_times` returns True, the result is a floating point
+ number.
+
+
+.. function:: getmtime(path)
+
+ Return the time of last modification of *path*. The return value is a number
+ giving the number of seconds since the epoch (see the :mod:`time` module).
+ Raise :exc:`os.error` if the file does not exist or is inaccessible.
+
+ .. versionadded:: 1.5.2
+
+ .. versionchanged:: 2.3
+ If :func:`os.stat_float_times` returns True, the result is a floating point
+ number.
+
+
+.. function:: getctime(path)
+
+ Return the system's ctime which, on some systems (like Unix) is the time of the
+ last change, and, on others (like Windows), is the creation time for *path*.
+ The return value is a number giving the number of seconds since the epoch (see
+ the :mod:`time` module). Raise :exc:`os.error` if the file does not exist or
+ is inaccessible.
+
+ .. versionadded:: 2.3
+
+
+.. function:: getsize(path)
+
+ Return the size, in bytes, of *path*. Raise :exc:`os.error` if the file does
+ not exist or is inaccessible.
+
+ .. versionadded:: 1.5.2
+
+
+.. function:: isabs(path)
+
+ Return ``True`` if *path* is an absolute pathname (begins with a slash).
+
+
+.. function:: isfile(path)
+
+ Return ``True`` if *path* is an existing regular file. This follows symbolic
+ links, so both :func:`islink` and :func:`isfile` can be true for the same path.
+
+
+.. function:: isdir(path)
+
+ Return ``True`` if *path* is an existing directory. This follows symbolic
+ links, so both :func:`islink` and :func:`isdir` can be true for the same path.
+
+
+.. function:: islink(path)
+
+ Return ``True`` if *path* refers to a directory entry that is a symbolic link.
+ Always ``False`` if symbolic links are not supported.
+
+
+.. function:: ismount(path)
+
+ Return ``True`` if pathname *path* is a :dfn:`mount point`: a point in a file
+ system where a different file system has been mounted. The function checks
+ whether *path*'s parent, :file:`path/..`, is on a different device than *path*,
+ or whether :file:`path/..` and *path* point to the same i-node on the same
+ device --- this should detect mount points for all Unix and POSIX variants.
+
+
+.. function:: join(path1[, path2[, ...]])
+
+ Join one or more path components intelligently. If any component is an absolute
+ path, all previous components (on Windows, including the previous drive letter,
+ if there was one) are thrown away, and joining continues. The return value is
+ the concatenation of *path1*, and optionally *path2*, etc., with exactly one
+ directory separator (``os.sep``) inserted between components, unless *path2* is
+ empty. Note that on Windows, since there is a current directory for each drive,
+ ``os.path.join("c:", "foo")`` represents a path relative to the current
+ directory on drive :file:`C:` (:file:`c:foo`), not :file:`c:\\foo`.
+
+
+.. function:: normcase(path)
+
+ Normalize the case of a pathname. On Unix, this returns the path unchanged; on
+ case-insensitive filesystems, it converts the path to lowercase. On Windows, it
+ also converts forward slashes to backward slashes.
+
+
+.. function:: normpath(path)
+
+ Normalize a pathname. This collapses redundant separators and up-level
+ references so that ``A//B``, ``A/./B`` and ``A/foo/../B`` all become ``A/B``.
+ It does not normalize the case (use :func:`normcase` for that). On Windows, it
+ converts forward slashes to backward slashes. It should be understood that this
+ may change the meaning of the path if it contains symbolic links!
+
+
+.. function:: realpath(path)
+
+ Return the canonical path of the specified filename, eliminating any symbolic
+ links encountered in the path (if they are supported by the operating system).
+
+ .. versionadded:: 2.2
+
+
+.. function:: relpath(path[, start])
+
+ Return a relative filepath to *path* either from the current directory or from
+ an optional *start* point.
+
+ *start* defaults to :attr:`os.curdir`. Availability: Windows, Unix.
+
+ .. versionadded:: 2.6
+
+
+.. function:: samefile(path1, path2)
+
+ Return ``True`` if both pathname arguments refer to the same file or directory
+ (as indicated by device number and i-node number). Raise an exception if a
+ :func:`os.stat` call on either pathname fails. Availability: Macintosh, Unix.
+
+
+.. function:: sameopenfile(fp1, fp2)
+
+ Return ``True`` if the file descriptors *fp1* and *fp2* refer to the same file.
+ Availability: Macintosh, Unix.
+
+
+.. function:: samestat(stat1, stat2)
+
+ Return ``True`` if the stat tuples *stat1* and *stat2* refer to the same file.
+ These structures may have been returned by :func:`fstat`, :func:`lstat`, or
+ :func:`stat`. This function implements the underlying comparison used by
+ :func:`samefile` and :func:`sameopenfile`. Availability: Macintosh, Unix.
+
+
+.. function:: split(path)
+
+ Split the pathname *path* into a pair, ``(head, tail)`` where *tail* is the last
+ pathname component and *head* is everything leading up to that. The *tail* part
+ will never contain a slash; if *path* ends in a slash, *tail* will be empty. If
+ there is no slash in *path*, *head* will be empty. If *path* is empty, both
+ *head* and *tail* are empty. Trailing slashes are stripped from *head* unless
+ it is the root (one or more slashes only). In nearly all cases, ``join(head,
+ tail)`` equals *path* (the only exception being when there were multiple slashes
+ separating *head* from *tail*).
+
+
+.. function:: splitdrive(path)
+
+ Split the pathname *path* into a pair ``(drive, tail)`` where *drive* is either
+ a drive specification or the empty string. On systems which do not use drive
+ specifications, *drive* will always be the empty string. In all cases, ``drive
+ + tail`` will be the same as *path*.
+
+ .. versionadded:: 1.3
+
+
+.. function:: splitext(path)
+
+ Split the pathname *path* into a pair ``(root, ext)`` such that ``root + ext ==
+ path``, and *ext* is empty or begins with a period and contains at most one
+ period. Leading periods on the basename are ignored; ``splitext('.cshrc')``
+ returns ``('.cshrc', '')``.
+
+ .. versionchanged:: 2.6
+ Earlier versions could produce an empty root when the only period was the
+ first character.
+
+
+.. function:: splitunc(path)
+
+ Split the pathname *path* into a pair ``(unc, rest)`` so that *unc* is the UNC
+ mount point (such as ``r'\\host\mount'``), if present, and *rest* the rest of
+ the path (such as ``r'\path\file.ext'``). For paths containing drive letters,
+ *unc* will always be the empty string. Availability: Windows.
+
+
+.. function:: walk(path, visit, arg)
+
+ Calls the function *visit* with arguments ``(arg, dirname, names)`` for each
+ directory in the directory tree rooted at *path* (including *path* itself, if it
+ is a directory). The argument *dirname* specifies the visited directory, the
+ argument *names* lists the files in the directory (gotten from
+ ``os.listdir(dirname)``). The *visit* function may modify *names* to influence
+ the set of directories visited below *dirname*, e.g. to avoid visiting certain
+ parts of the tree. (The object referred to by *names* must be modified in
+ place, using :keyword:`del` or slice assignment.)
+
+ .. note::
+
+ Symbolic links to directories are not treated as subdirectories, and that
+ :func:`walk` therefore will not visit them. To visit linked directories you must
+ identify them with ``os.path.islink(file)`` and ``os.path.isdir(file)``, and
+ invoke :func:`walk` as necessary.
+
+ .. note::
+
+ The newer :func:`os.walk` generator supplies similar functionality and can be
+ easier to use.
+
+
+.. data:: supports_unicode_filenames
+
+ True if arbitrary Unicode strings can be used as file names (within limitations
+ imposed by the file system), and if :func:`os.listdir` returns Unicode strings
+ for a Unicode argument.
+
+ .. versionadded:: 2.3
+
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
new file mode 100644
index 0000000000..5d057f1161
--- /dev/null
+++ b/Doc/library/os.rst
@@ -0,0 +1,2036 @@
+
+:mod:`os` --- Miscellaneous operating system interfaces
+=======================================================
+
+.. module:: os
+ :synopsis: Miscellaneous operating system interfaces.
+
+
+This module provides a more portable way of using operating system dependent
+functionality than importing a operating system dependent built-in module like
+:mod:`posix` or :mod:`nt`. (If you just want to read or write a file see
+:func:`open`, and if you want to manipulate paths, see the :mod:`os.path`
+module.)
+
+This module searches for an operating system dependent built-in module like
+:mod:`mac` or :mod:`posix` and exports the same functions and data as found
+there. The design of all Python's built-in operating system dependent modules
+is such that as long as the same functionality is available, it uses the same
+interface; for example, the function ``os.stat(path)`` returns stat information
+about *path* in the same format (which happens to have originated with the POSIX
+interface).
+
+Extensions peculiar to a particular operating system are also available through
+the :mod:`os` module, but using them is of course a threat to portability!
+
+Note that after the first time :mod:`os` is imported, there is *no* performance
+penalty in using functions from :mod:`os` instead of directly from the operating
+system dependent built-in module, so there should be *no* reason not to use
+:mod:`os`!
+
+The :mod:`os` module contains many functions and data values. The items below
+and in the following sub-sections are all available directly from the :mod:`os`
+module.
+
+.. % Frank Stajano <fstajano@uk.research.att.com> complained that it
+.. % wasn't clear that the entries described in the subsections were all
+.. % available at the module level (most uses of subsections are
+.. % different); I think this is only a problem for the HTML version,
+.. % where the relationship may not be as clear.
+.. %
+
+
+.. exception:: error
+
+ .. index:: module: errno
+
+ This exception is raised when a function returns a system-related error (not for
+ illegal argument types or other incidental errors). This is also known as the
+ built-in exception :exc:`OSError`. The accompanying value is a pair containing
+ the numeric error code from :cdata:`errno` and the corresponding string, as
+ would be printed by the C function :cfunc:`perror`. See the module
+ :mod:`errno`, which contains names for the error codes defined by the underlying
+ operating system.
+
+ When exceptions are classes, this exception carries two attributes,
+ :attr:`errno` and :attr:`strerror`. The first holds the value of the C
+ :cdata:`errno` variable, and the latter holds the corresponding error message
+ from :cfunc:`strerror`. For exceptions that involve a file system path (such as
+ :func:`chdir` or :func:`unlink`), the exception instance will contain a third
+ attribute, :attr:`filename`, which is the file name passed to the function.
+
+
+.. data:: name
+
+ The name of the operating system dependent module imported. The following names
+ have currently been registered: ``'posix'``, ``'nt'``, ``'mac'``, ``'os2'``,
+ ``'ce'``, ``'java'``, ``'riscos'``.
+
+
+.. data:: path
+
+ The corresponding operating system dependent standard module for pathname
+ operations, such as :mod:`posixpath` or :mod:`macpath`. Thus, given the proper
+ imports, ``os.path.split(file)`` is equivalent to but more portable than
+ ``posixpath.split(file)``. Note that this is also an importable module: it may
+ be imported directly as :mod:`os.path`.
+
+
+.. _os-procinfo:
+
+Process Parameters
+------------------
+
+These functions and data items provide information and operate on the current
+process and user.
+
+
+.. data:: environ
+
+ A mapping object representing the string environment. For example,
+ ``environ['HOME']`` is the pathname of your home directory (on some platforms),
+ and is equivalent to ``getenv("HOME")`` in C.
+
+ This mapping is captured the first time the :mod:`os` module is imported,
+ typically during Python startup as part of processing :file:`site.py`. Changes
+ to the environment made after this time are not reflected in ``os.environ``,
+ except for changes made by modifying ``os.environ`` directly.
+
+ If the platform supports the :func:`putenv` function, this mapping may be used
+ to modify the environment as well as query the environment. :func:`putenv` will
+ be called automatically when the mapping is modified.
+
+ .. note::
+
+ Calling :func:`putenv` directly does not change ``os.environ``, so it's better
+ to modify ``os.environ``.
+
+ .. note::
+
+ On some platforms, including FreeBSD and Mac OS X, setting ``environ`` may cause
+ memory leaks. Refer to the system documentation for :cfunc:`putenv`.
+
+ If :func:`putenv` is not provided, a modified copy of this mapping may be
+ passed to the appropriate process-creation functions to cause child processes
+ to use a modified environment.
+
+ If the platform supports the :func:`unsetenv` function, you can delete items in
+ this mapping to unset environment variables. :func:`unsetenv` will be called
+ automatically when an item is deleted from ``os.environ``.
+
+
+.. function:: chdir(path)
+ fchdir(fd)
+ getcwd()
+ :noindex:
+
+ These functions are described in :ref:`os-file-dir`.
+
+
+.. function:: ctermid()
+
+ Return the filename corresponding to the controlling terminal of the process.
+ Availability: Unix.
+
+
+.. function:: getegid()
+
+ Return the effective group id of the current process. This corresponds to the
+ 'set id' bit on the file being executed in the current process. Availability:
+ Unix.
+
+
+.. function:: geteuid()
+
+ .. index:: single: user; effective id
+
+ Return the current process' effective user id. Availability: Unix.
+
+
+.. function:: getgid()
+
+ .. index:: single: process; group
+
+ Return the real group id of the current process. Availability: Unix.
+
+
+.. function:: getgroups()
+
+ Return list of supplemental group ids associated with the current process.
+ Availability: Unix.
+
+
+.. function:: getlogin()
+
+ Return the name of the user logged in on the controlling terminal of the
+ process. For most purposes, it is more useful to use the environment variable
+ :envvar:`LOGNAME` to find out who the user is, or
+ ``pwd.getpwuid(os.getuid())[0]`` to get the login name of the currently
+ effective user ID. Availability: Unix.
+
+
+.. function:: getpgid(pid)
+
+ Return the process group id of the process with process id *pid*. If *pid* is 0,
+ the process group id of the current process is returned. Availability: Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: getpgrp()
+
+ .. index:: single: process; group
+
+ Return the id of the current process group. Availability: Unix.
+
+
+.. function:: getpid()
+
+ .. index:: single: process; id
+
+ Return the current process id. Availability: Unix, Windows.
+
+
+.. function:: getppid()
+
+ .. index:: single: process; id of parent
+
+ Return the parent's process id. Availability: Unix.
+
+
+.. function:: getuid()
+
+ .. index:: single: user; id
+
+ Return the current process' user id. Availability: Unix.
+
+
+.. function:: getenv(varname[, value])
+
+ Return the value of the environment variable *varname* if it exists, or *value*
+ if it doesn't. *value* defaults to ``None``. Availability: most flavors of
+ Unix, Windows.
+
+
+.. function:: putenv(varname, value)
+
+ .. index:: single: environment variables; setting
+
+ Set the environment variable named *varname* to the string *value*. Such
+ changes to the environment affect subprocesses started with :func:`os.system`,
+ :func:`popen` or :func:`fork` and :func:`execv`. Availability: most flavors of
+ Unix, Windows.
+
+ .. note::
+
+ On some platforms, including FreeBSD and Mac OS X, setting ``environ`` may cause
+ memory leaks. Refer to the system documentation for putenv.
+
+ When :func:`putenv` is supported, assignments to items in ``os.environ`` are
+ automatically translated into corresponding calls to :func:`putenv`; however,
+ calls to :func:`putenv` don't update ``os.environ``, so it is actually
+ preferable to assign to items of ``os.environ``.
+
+
+.. function:: setegid(egid)
+
+ Set the current process's effective group id. Availability: Unix.
+
+
+.. function:: seteuid(euid)
+
+ Set the current process's effective user id. Availability: Unix.
+
+
+.. function:: setgid(gid)
+
+ Set the current process' group id. Availability: Unix.
+
+
+.. function:: setgroups(groups)
+
+ Set the list of supplemental group ids associated with the current process to
+ *groups*. *groups* must be a sequence, and each element must be an integer
+ identifying a group. This operation is typical available only to the superuser.
+ Availability: Unix.
+
+ .. versionadded:: 2.2
+
+
+.. function:: setpgrp()
+
+ Calls the system call :cfunc:`setpgrp` or :cfunc:`setpgrp(0, 0)` depending on
+ which version is implemented (if any). See the Unix manual for the semantics.
+ Availability: Unix.
+
+
+.. function:: setpgid(pid, pgrp)
+
+ Calls the system call :cfunc:`setpgid` to set the process group id of the
+ process with id *pid* to the process group with id *pgrp*. See the Unix manual
+ for the semantics. Availability: Unix.
+
+
+.. function:: setreuid(ruid, euid)
+
+ Set the current process's real and effective user ids. Availability: Unix.
+
+
+.. function:: setregid(rgid, egid)
+
+ Set the current process's real and effective group ids. Availability: Unix.
+
+
+.. function:: getsid(pid)
+
+ Calls the system call :cfunc:`getsid`. See the Unix manual for the semantics.
+ Availability: Unix.
+
+ .. versionadded:: 2.4
+
+
+.. function:: setsid()
+
+ Calls the system call :cfunc:`setsid`. See the Unix manual for the semantics.
+ Availability: Unix.
+
+
+.. function:: setuid(uid)
+
+ .. index:: single: user; id, setting
+
+ Set the current process' user id. Availability: Unix.
+
+.. % placed in this section since it relates to errno.... a little weak
+
+
+.. function:: strerror(code)
+
+ Return the error message corresponding to the error code in *code*.
+ Availability: Unix, Windows.
+
+
+.. function:: umask(mask)
+
+ Set the current numeric umask and returns the previous umask. Availability:
+ Unix, Windows.
+
+
+.. function:: uname()
+
+ .. index::
+ single: gethostname() (in module socket)
+ single: gethostbyaddr() (in module socket)
+
+ Return a 5-tuple containing information identifying the current operating
+ system. The tuple contains 5 strings: ``(sysname, nodename, release, version,
+ machine)``. Some systems truncate the nodename to 8 characters or to the
+ leading component; a better way to get the hostname is
+ :func:`socket.gethostname` or even
+ ``socket.gethostbyaddr(socket.gethostname())``. Availability: recent flavors of
+ Unix.
+
+
+.. function:: unsetenv(varname)
+
+ .. index:: single: environment variables; deleting
+
+ Unset (delete) the environment variable named *varname*. Such changes to the
+ environment affect subprocesses started with :func:`os.system`, :func:`popen` or
+ :func:`fork` and :func:`execv`. Availability: most flavors of Unix, Windows.
+
+ When :func:`unsetenv` is supported, deletion of items in ``os.environ`` is
+ automatically translated into a corresponding call to :func:`unsetenv`; however,
+ calls to :func:`unsetenv` don't update ``os.environ``, so it is actually
+ preferable to delete items of ``os.environ``.
+
+
+.. _os-newstreams:
+
+File Object Creation
+--------------------
+
+These functions create new file objects. (See also :func:`open`.)
+
+
+.. function:: fdopen(fd[, mode[, bufsize]])
+
+ .. index:: single: I/O control; buffering
+
+ Return an open file object connected to the file descriptor *fd*. The *mode*
+ and *bufsize* arguments have the same meaning as the corresponding arguments to
+ the built-in :func:`open` function. Availability: Macintosh, Unix, Windows.
+
+ .. versionchanged:: 2.3
+ When specified, the *mode* argument must now start with one of the letters
+ ``'r'``, ``'w'``, or ``'a'``, otherwise a :exc:`ValueError` is raised.
+
+ .. versionchanged:: 2.5
+ On Unix, when the *mode* argument starts with ``'a'``, the *O_APPEND* flag is
+ set on the file descriptor (which the :cfunc:`fdopen` implementation already
+ does on most platforms).
+
+
+.. function:: popen(command[, mode[, bufsize]])
+
+ Open a pipe to or from *command*. The return value is an open file object
+ connected to the pipe, which can be read or written depending on whether *mode*
+ is ``'r'`` (default) or ``'w'``. The *bufsize* argument has the same meaning as
+ the corresponding argument to the built-in :func:`open` function. The exit
+ status of the command (encoded in the format specified for :func:`wait`) is
+ available as the return value of the :meth:`close` method of the file object,
+ except that when the exit status is zero (termination without errors), ``None``
+ is returned. Availability: Macintosh, Unix, Windows.
+
+ .. deprecated:: 2.6
+ This function is obsolete. Use the :mod:`subprocess` module.
+
+ .. versionchanged:: 2.0
+ This function worked unreliably under Windows in earlier versions of Python.
+ This was due to the use of the :cfunc:`_popen` function from the libraries
+ provided with Windows. Newer versions of Python do not use the broken
+ implementation from the Windows libraries.
+
+
+.. function:: tmpfile()
+
+ Return a new file object opened in update mode (``w+b``). The file has no
+ directory entries associated with it and will be automatically deleted once
+ there are no file descriptors for the file. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. _os-fd-ops:
+
+File Descriptor Operations
+--------------------------
+
+These functions operate on I/O streams referenced using file descriptors.
+
+File descriptors are small integers corresponding to a file that has been opened
+by the current process. For example, standard input is usually file descriptor
+0, standard output is 1, and standard error is 2. Further files opened by a
+process will then be assigned 3, 4, 5, and so forth. The name "file descriptor"
+is slightly deceptive; on Unix platforms, sockets and pipes are also referenced
+by file descriptors.
+
+
+.. function:: close(fd)
+
+ Close file descriptor *fd*. Availability: Macintosh, Unix, Windows.
+
+ .. note::
+
+ This function is intended for low-level I/O and must be applied to a file
+ descriptor as returned by :func:`open` or :func:`pipe`. To close a "file
+ object" returned by the built-in function :func:`open` or by :func:`popen` or
+ :func:`fdopen`, use its :meth:`close` method.
+
+
+.. function:: dup(fd)
+
+ Return a duplicate of file descriptor *fd*. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. function:: dup2(fd, fd2)
+
+ Duplicate file descriptor *fd* to *fd2*, closing the latter first if necessary.
+ Availability: Macintosh, Unix, Windows.
+
+
+.. function:: fdatasync(fd)
+
+ Force write of file with filedescriptor *fd* to disk. Does not force update of
+ metadata. Availability: Unix.
+
+
+.. function:: fpathconf(fd, name)
+
+ Return system configuration information relevant to an open file. *name*
+ specifies the configuration value to retrieve; it may be a string which is the
+ name of a defined system value; these names are specified in a number of
+ standards (POSIX.1, Unix 95, Unix 98, and others). Some platforms define
+ additional names as well. The names known to the host operating system are
+ given in the ``pathconf_names`` dictionary. For configuration variables not
+ included in that mapping, passing an integer for *name* is also accepted.
+ Availability: Macintosh, Unix.
+
+ If *name* is a string and is not known, :exc:`ValueError` is raised. If a
+ specific value for *name* is not supported by the host system, even if it is
+ included in ``pathconf_names``, an :exc:`OSError` is raised with
+ :const:`errno.EINVAL` for the error number.
+
+
+.. function:: fstat(fd)
+
+ Return status for file descriptor *fd*, like :func:`stat`. Availability:
+ Macintosh, Unix, Windows.
+
+
+.. function:: fstatvfs(fd)
+
+ Return information about the filesystem containing the file associated with file
+ descriptor *fd*, like :func:`statvfs`. Availability: Unix.
+
+
+.. function:: fsync(fd)
+
+ Force write of file with filedescriptor *fd* to disk. On Unix, this calls the
+ native :cfunc:`fsync` function; on Windows, the MS :cfunc:`_commit` function.
+
+ If you're starting with a Python file object *f*, first do ``f.flush()``, and
+ then do ``os.fsync(f.fileno())``, to ensure that all internal buffers associated
+ with *f* are written to disk. Availability: Macintosh, Unix, and Windows
+ starting in 2.2.3.
+
+
+.. function:: ftruncate(fd, length)
+
+ Truncate the file corresponding to file descriptor *fd*, so that it is at most
+ *length* bytes in size. Availability: Macintosh, Unix.
+
+
+.. function:: isatty(fd)
+
+ Return ``True`` if the file descriptor *fd* is open and connected to a
+ tty(-like) device, else ``False``. Availability: Macintosh, Unix.
+
+
+.. function:: lseek(fd, pos, how)
+
+ Set the current position of file descriptor *fd* to position *pos*, modified by
+ *how*: ``0`` to set the position relative to the beginning of the file; ``1`` to
+ set it relative to the current position; ``2`` to set it relative to the end of
+ the file. Availability: Macintosh, Unix, Windows.
+
+
+.. function:: open(file, flags[, mode])
+
+ Open the file *file* and set various flags according to *flags* and possibly its
+ mode according to *mode*. The default *mode* is ``0777`` (octal), and the
+ current umask value is first masked out. Return the file descriptor for the
+ newly opened file. Availability: Macintosh, Unix, Windows.
+
+ For a description of the flag and mode values, see the C run-time documentation;
+ flag constants (like :const:`O_RDONLY` and :const:`O_WRONLY`) are defined in
+ this module too (see below).
+
+ .. note::
+
+ This function is intended for low-level I/O. For normal usage, use the built-in
+ function :func:`open`, which returns a "file object" with :meth:`read` and
+ :meth:`write` methods (and many more). To wrap a file descriptor in a "file
+ object", use :func:`fdopen`.
+
+
+.. function:: openpty()
+
+ .. index:: module: pty
+
+ Open a new pseudo-terminal pair. Return a pair of file descriptors ``(master,
+ slave)`` for the pty and the tty, respectively. For a (slightly) more portable
+ approach, use the :mod:`pty` module. Availability: Macintosh, Some flavors of
+ Unix.
+
+
+.. function:: pipe()
+
+ Create a pipe. Return a pair of file descriptors ``(r, w)`` usable for reading
+ and writing, respectively. Availability: Macintosh, Unix, Windows.
+
+
+.. function:: read(fd, n)
+
+ Read at most *n* bytes from file descriptor *fd*. Return a string containing the
+ bytes read. If the end of the file referred to by *fd* has been reached, an
+ empty string is returned. Availability: Macintosh, Unix, Windows.
+
+ .. note::
+
+ This function is intended for low-level I/O and must be applied to a file
+ descriptor as returned by :func:`open` or :func:`pipe`. To read a "file object"
+ returned by the built-in function :func:`open` or by :func:`popen` or
+ :func:`fdopen`, or ``sys.stdin``, use its :meth:`read` or :meth:`readline`
+ methods.
+
+
+.. function:: tcgetpgrp(fd)
+
+ Return the process group associated with the terminal given by *fd* (an open
+ file descriptor as returned by :func:`open`). Availability: Macintosh, Unix.
+
+
+.. function:: tcsetpgrp(fd, pg)
+
+ Set the process group associated with the terminal given by *fd* (an open file
+ descriptor as returned by :func:`open`) to *pg*. Availability: Macintosh, Unix.
+
+
+.. function:: ttyname(fd)
+
+ Return a string which specifies the terminal device associated with
+ file-descriptor *fd*. If *fd* is not associated with a terminal device, an
+ exception is raised. Availability:Macintosh, Unix.
+
+
+.. function:: write(fd, str)
+
+ Write the string *str* to file descriptor *fd*. Return the number of bytes
+ actually written. Availability: Macintosh, Unix, Windows.
+
+ .. note::
+
+ This function is intended for low-level I/O and must be applied to a file
+ descriptor as returned by :func:`open` or :func:`pipe`. To write a "file
+ object" returned by the built-in function :func:`open` or by :func:`popen` or
+ :func:`fdopen`, or ``sys.stdout`` or ``sys.stderr``, use its :meth:`write`
+ method.
+
+The following data items are available for use in constructing the *flags*
+parameter to the :func:`open` function. Some items will not be available on all
+platforms. For descriptions of their availability and use, consult
+:manpage:`open(2)`.
+
+
+.. data:: O_RDONLY
+ O_WRONLY
+ O_RDWR
+ O_APPEND
+ O_CREAT
+ O_EXCL
+ O_TRUNC
+
+ Options for the *flag* argument to the :func:`open` function. These can be
+ bit-wise OR'd together. Availability: Macintosh, Unix, Windows.
+
+
+.. data:: O_DSYNC
+ O_RSYNC
+ O_SYNC
+ O_NDELAY
+ O_NONBLOCK
+ O_NOCTTY
+ O_SHLOCK
+ O_EXLOCK
+
+ More options for the *flag* argument to the :func:`open` function. Availability:
+ Macintosh, Unix.
+
+
+.. data:: O_BINARY
+
+ Option for the *flag* argument to the :func:`open` function. This can be
+ bit-wise OR'd together with those listed above. Availability: Windows.
+
+ .. % XXX need to check on the availability of this one.
+
+
+.. data:: O_NOINHERIT
+ O_SHORT_LIVED
+ O_TEMPORARY
+ O_RANDOM
+ O_SEQUENTIAL
+ O_TEXT
+
+ Options for the *flag* argument to the :func:`open` function. These can be
+ bit-wise OR'd together. Availability: Windows.
+
+
+.. data:: SEEK_SET
+ SEEK_CUR
+ SEEK_END
+
+ Parameters to the :func:`lseek` function. Their values are 0, 1, and 2,
+ respectively. Availability: Windows, Macintosh, Unix.
+
+ .. versionadded:: 2.5
+
+
+.. _os-file-dir:
+
+Files and Directories
+---------------------
+
+
+.. function:: access(path, mode)
+
+ Use the real uid/gid to test for access to *path*. Note that most operations
+ will use the effective uid/gid, therefore this routine can be used in a
+ suid/sgid environment to test if the invoking user has the specified access to
+ *path*. *mode* should be :const:`F_OK` to test the existence of *path*, or it
+ can be the inclusive OR of one or more of :const:`R_OK`, :const:`W_OK`, and
+ :const:`X_OK` to test permissions. Return :const:`True` if access is allowed,
+ :const:`False` if not. See the Unix man page :manpage:`access(2)` for more
+ information. Availability: Macintosh, Unix, Windows.
+
+ .. note::
+
+ Using :func:`access` to check if a user is authorized to e.g. open a file before
+ actually doing so using :func:`open` creates a security hole, because the user
+ might exploit the short time interval between checking and opening the file to
+ manipulate it.
+
+ .. note::
+
+ I/O operations may fail even when :func:`access` indicates that they would
+ succeed, particularly for operations on network filesystems which may have
+ permissions semantics beyond the usual POSIX permission-bit model.
+
+
+.. data:: F_OK
+
+ Value to pass as the *mode* parameter of :func:`access` to test the existence of
+ *path*.
+
+
+.. data:: R_OK
+
+ Value to include in the *mode* parameter of :func:`access` to test the
+ readability of *path*.
+
+
+.. data:: W_OK
+
+ Value to include in the *mode* parameter of :func:`access` to test the
+ writability of *path*.
+
+
+.. data:: X_OK
+
+ Value to include in the *mode* parameter of :func:`access` to determine if
+ *path* can be executed.
+
+
+.. function:: chdir(path)
+
+ .. index:: single: directory; changing
+
+ Change the current working directory to *path*. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. function:: fchdir(fd)
+
+ Change the current working directory to the directory represented by the file
+ descriptor *fd*. The descriptor must refer to an opened directory, not an open
+ file. Availability: Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: getcwd()
+
+ Return a string representing the current working directory. Availability:
+ Macintosh, Unix, Windows.
+
+
+.. function:: getcwdu()
+
+ Return a Unicode object representing the current working directory.
+ Availability: Macintosh, Unix, Windows.
+
+ .. versionadded:: 2.3
+
+
+.. function:: chflags(path, flags)
+
+ Set the flags of *path* to the numeric *flags*. *flags* may take a combination
+ (bitwise OR) of the following values (as defined in the :mod:`stat` module):
+
+ * ``UF_NODUMP``
+ * ``UF_IMMUTABLE``
+ * ``UF_APPEND``
+ * ``UF_OPAQUE``
+ * ``UF_NOUNLINK``
+ * ``SF_ARCHIVED``
+ * ``SF_IMMUTABLE``
+ * ``SF_APPEND``
+ * ``SF_NOUNLINK``
+ * ``SF_SNAPSHOT``
+
+ Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.6
+
+
+.. function:: chroot(path)
+
+ Change the root directory of the current process to *path*. Availability:
+ Macintosh, Unix.
+
+ .. versionadded:: 2.2
+
+
+.. function:: chmod(path, mode)
+
+ Change the mode of *path* to the numeric *mode*. *mode* may take one of the
+ following values (as defined in the :mod:`stat` module) or bitwise or-ed
+ combinations of them:
+
+ * ``stat.S_ISUID``
+ * ``stat.S_ISGID``
+ * ``stat.S_ENFMT``
+ * ``stat.S_ISVTX``
+ * ``stat.S_IREAD``
+ * ``stat.S_IWRITE``
+ * ``stat.S_IEXEC``
+ * ``stat.S_IRWXU``
+ * ``stat.S_IRUSR``
+ * ``stat.S_IWUSR``
+ * ``stat.S_IXUSR``
+ * ``stat.S_IRWXG``
+ * ``stat.S_IRGRP``
+ * ``stat.S_IWGRP``
+ * ``stat.S_IXGRP``
+ * ``stat.S_IRWXO``
+ * ``stat.S_IROTH``
+ * ``stat.S_IWOTH``
+ * ``stat.S_IXOTH``
+
+ Availability: Macintosh, Unix, Windows.
+
+ .. note::
+
+ Although Windows supports :func:`chmod`, you can only set the file's read-only
+ flag with it (via the ``stat.S_IWRITE`` and ``stat.S_IREAD``
+ constants or a corresponding integer value). All other bits are
+ ignored.
+
+
+.. function:: chown(path, uid, gid)
+
+ Change the owner and group id of *path* to the numeric *uid* and *gid*. To leave
+ one of the ids unchanged, set it to -1. Availability: Macintosh, Unix.
+
+
+.. function:: lchflags(path, flags)
+
+ Set the flags of *path* to the numeric *flags*, like :func:`chflags`, but do not
+ follow symbolic links. Availability: Unix.
+
+ .. versionadded:: 2.6
+
+
+.. function:: lchown(path, uid, gid)
+
+ Change the owner and group id of *path* to the numeric *uid* and gid. This
+ function will not follow symbolic links. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: link(src, dst)
+
+ Create a hard link pointing to *src* named *dst*. Availability: Macintosh, Unix.
+
+
+.. function:: listdir(path)
+
+ Return a list containing the names of the entries in the directory. The list is
+ in arbitrary order. It does not include the special entries ``'.'`` and
+ ``'..'`` even if they are present in the directory. Availability: Macintosh,
+ Unix, Windows.
+
+ .. versionchanged:: 2.3
+ On Windows NT/2k/XP and Unix, if *path* is a Unicode object, the result will be
+ a list of Unicode objects.
+
+
+.. function:: lstat(path)
+
+ Like :func:`stat`, but do not follow symbolic links. Availability: Macintosh,
+ Unix.
+
+
+.. function:: mkfifo(path[, mode])
+
+ Create a FIFO (a named pipe) named *path* with numeric mode *mode*. The default
+ *mode* is ``0666`` (octal). The current umask value is first masked out from
+ the mode. Availability: Macintosh, Unix.
+
+ FIFOs are pipes that can be accessed like regular files. FIFOs exist until they
+ are deleted (for example with :func:`os.unlink`). Generally, FIFOs are used as
+ rendezvous between "client" and "server" type processes: the server opens the
+ FIFO for reading, and the client opens it for writing. Note that :func:`mkfifo`
+ doesn't open the FIFO --- it just creates the rendezvous point.
+
+
+.. function:: mknod(filename[, mode=0600, device])
+
+ Create a filesystem node (file, device special file or named pipe) named
+ *filename*. *mode* specifies both the permissions to use and the type of node to
+ be created, being combined (bitwise OR) with one of ``stat.S_IFREG``,
+ ``stat.S_IFCHR``, ``stat.S_IFBLK``,
+ and ``stat.S_IFIFO`` (those constants are available in :mod:`stat`).
+ For ``stat.S_IFCHR`` and
+ ``stat.S_IFBLK``, *device* defines the newly created device special file (probably using
+ :func:`os.makedev`), otherwise it is ignored.
+
+ .. versionadded:: 2.3
+
+
+.. function:: major(device)
+
+ Extracts the device major number from a raw device number (usually the
+ :attr:`st_dev` or :attr:`st_rdev` field from :ctype:`stat`).
+
+ .. versionadded:: 2.3
+
+
+.. function:: minor(device)
+
+ Extracts the device minor number from a raw device number (usually the
+ :attr:`st_dev` or :attr:`st_rdev` field from :ctype:`stat`).
+
+ .. versionadded:: 2.3
+
+
+.. function:: makedev(major, minor)
+
+ Composes a raw device number from the major and minor device numbers.
+
+ .. versionadded:: 2.3
+
+
+.. function:: mkdir(path[, mode])
+
+ Create a directory named *path* with numeric mode *mode*. The default *mode* is
+ ``0777`` (octal). On some systems, *mode* is ignored. Where it is used, the
+ current umask value is first masked out. Availability: Macintosh, Unix, Windows.
+
+
+.. function:: makedirs(path[, mode])
+
+ .. index::
+ single: directory; creating
+ single: UNC paths; and os.makedirs()
+
+ Recursive directory creation function. Like :func:`mkdir`, but makes all
+ intermediate-level directories needed to contain the leaf directory. Throws an
+ :exc:`error` exception if the leaf directory already exists or cannot be
+ created. The default *mode* is ``0777`` (octal). On some systems, *mode* is
+ ignored. Where it is used, the current umask value is first masked out.
+
+ .. note::
+
+ :func:`makedirs` will become confused if the path elements to create include
+ *os.pardir*.
+
+ .. versionadded:: 1.5.2
+
+ .. versionchanged:: 2.3
+ This function now handles UNC paths correctly.
+
+
+.. function:: pathconf(path, name)
+
+ Return system configuration information relevant to a named file. *name*
+ specifies the configuration value to retrieve; it may be a string which is the
+ name of a defined system value; these names are specified in a number of
+ standards (POSIX.1, Unix 95, Unix 98, and others). Some platforms define
+ additional names as well. The names known to the host operating system are
+ given in the ``pathconf_names`` dictionary. For configuration variables not
+ included in that mapping, passing an integer for *name* is also accepted.
+ Availability: Macintosh, Unix.
+
+ If *name* is a string and is not known, :exc:`ValueError` is raised. If a
+ specific value for *name* is not supported by the host system, even if it is
+ included in ``pathconf_names``, an :exc:`OSError` is raised with
+ :const:`errno.EINVAL` for the error number.
+
+
+.. data:: pathconf_names
+
+ Dictionary mapping names accepted by :func:`pathconf` and :func:`fpathconf` to
+ the integer values defined for those names by the host operating system. This
+ can be used to determine the set of names known to the system. Availability:
+ Macintosh, Unix.
+
+
+.. function:: readlink(path)
+
+ Return a string representing the path to which the symbolic link points. The
+ result may be either an absolute or relative pathname; if it is relative, it may
+ be converted to an absolute pathname using ``os.path.join(os.path.dirname(path),
+ result)``.
+
+ .. versionchanged:: 2.6
+ If the *path* is a Unicode object the result will also be a Unicode object.
+
+ Availability: Macintosh, Unix.
+
+
+.. function:: remove(path)
+
+ Remove the file *path*. If *path* is a directory, :exc:`OSError` is raised; see
+ :func:`rmdir` below to remove a directory. This is identical to the
+ :func:`unlink` function documented below. On Windows, attempting to remove a
+ file that is in use causes an exception to be raised; on Unix, the directory
+ entry is removed but the storage allocated to the file is not made available
+ until the original file is no longer in use. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. function:: removedirs(path)
+
+ .. index:: single: directory; deleting
+
+ Removes directories recursively. Works like :func:`rmdir` except that, if the
+ leaf directory is successfully removed, :func:`removedirs` tries to
+ successively remove every parent directory mentioned in *path* until an error
+ is raised (which is ignored, because it generally means that a parent directory
+ is not empty). For example, ``os.removedirs('foo/bar/baz')`` will first remove
+ the directory ``'foo/bar/baz'``, and then remove ``'foo/bar'`` and ``'foo'`` if
+ they are empty. Raises :exc:`OSError` if the leaf directory could not be
+ successfully removed.
+
+ .. versionadded:: 1.5.2
+
+
+.. function:: rename(src, dst)
+
+ Rename the file or directory *src* to *dst*. If *dst* is a directory,
+ :exc:`OSError` will be raised. On Unix, if *dst* exists and is a file, it will
+ be removed silently if the user has permission. The operation may fail on some
+ Unix flavors if *src* and *dst* are on different filesystems. If successful,
+ the renaming will be an atomic operation (this is a POSIX requirement). On
+ Windows, if *dst* already exists, :exc:`OSError` will be raised even if it is a
+ file; there may be no way to implement an atomic rename when *dst* names an
+ existing file. Availability: Macintosh, Unix, Windows.
+
+
+.. function:: renames(old, new)
+
+ Recursive directory or file renaming function. Works like :func:`rename`, except
+ creation of any intermediate directories needed to make the new pathname good is
+ attempted first. After the rename, directories corresponding to rightmost path
+ segments of the old name will be pruned away using :func:`removedirs`.
+
+ .. versionadded:: 1.5.2
+
+ .. note::
+
+ This function can fail with the new directory structure made if you lack
+ permissions needed to remove the leaf directory or file.
+
+
+.. function:: rmdir(path)
+
+ Remove the directory *path*. Availability: Macintosh, Unix, Windows.
+
+
+.. function:: stat(path)
+
+ Perform a :cfunc:`stat` system call on the given path. The return value is an
+ object whose attributes correspond to the members of the :ctype:`stat`
+ structure, namely: :attr:`st_mode` (protection bits), :attr:`st_ino` (inode
+ number), :attr:`st_dev` (device), :attr:`st_nlink` (number of hard links),
+ :attr:`st_uid` (user ID of owner), :attr:`st_gid` (group ID of owner),
+ :attr:`st_size` (size of file, in bytes), :attr:`st_atime` (time of most recent
+ access), :attr:`st_mtime` (time of most recent content modification),
+ :attr:`st_ctime` (platform dependent; time of most recent metadata change on
+ Unix, or the time of creation on Windows)::
+
+ >>> import os
+ >>> statinfo = os.stat('somefile.txt')
+ >>> statinfo
+ (33188, 422511L, 769L, 1, 1032, 100, 926L, 1105022698,1105022732, 1105022732)
+ >>> statinfo.st_size
+ 926L
+ >>>
+
+ .. versionchanged:: 2.3
+ If :func:`stat_float_times` returns true, the time values are floats, measuring
+ seconds. Fractions of a second may be reported if the system supports that. On
+ Mac OS, the times are always floats. See :func:`stat_float_times` for further
+ discussion.
+
+ On some Unix systems (such as Linux), the following attributes may also be
+ available: :attr:`st_blocks` (number of blocks allocated for file),
+ :attr:`st_blksize` (filesystem blocksize), :attr:`st_rdev` (type of device if an
+ inode device). :attr:`st_flags` (user defined flags for file).
+
+ On other Unix systems (such as FreeBSD), the following attributes may be
+ available (but may be only filled out if root tries to use them): :attr:`st_gen`
+ (file generation number), :attr:`st_birthtime` (time of file creation).
+
+ On Mac OS systems, the following attributes may also be available:
+ :attr:`st_rsize`, :attr:`st_creator`, :attr:`st_type`.
+
+ On RISCOS systems, the following attributes are also available: :attr:`st_ftype`
+ (file type), :attr:`st_attrs` (attributes), :attr:`st_obtype` (object type).
+
+ .. index:: module: stat
+
+ For backward compatibility, the return value of :func:`stat` is also accessible
+ as a tuple of at least 10 integers giving the most important (and portable)
+ members of the :ctype:`stat` structure, in the order :attr:`st_mode`,
+ :attr:`st_ino`, :attr:`st_dev`, :attr:`st_nlink`, :attr:`st_uid`,
+ :attr:`st_gid`, :attr:`st_size`, :attr:`st_atime`, :attr:`st_mtime`,
+ :attr:`st_ctime`. More items may be added at the end by some implementations.
+ The standard module :mod:`stat` defines functions and constants that are useful
+ for extracting information from a :ctype:`stat` structure. (On Windows, some
+ items are filled with dummy values.)
+
+ .. note::
+
+ The exact meaning and resolution of the :attr:`st_atime`, :attr:`st_mtime`, and
+ :attr:`st_ctime` members depends on the operating system and the file system.
+ For example, on Windows systems using the FAT or FAT32 file systems,
+ :attr:`st_mtime` has 2-second resolution, and :attr:`st_atime` has only 1-day
+ resolution. See your operating system documentation for details.
+
+ Availability: Macintosh, Unix, Windows.
+
+ .. versionchanged:: 2.2
+ Added access to values as attributes of the returned object.
+
+ .. versionchanged:: 2.5
+ Added st_gen, st_birthtime.
+
+
+.. function:: stat_float_times([newvalue])
+
+ Determine whether :class:`stat_result` represents time stamps as float objects.
+ If *newvalue* is ``True``, future calls to :func:`stat` return floats, if it is
+ ``False``, future calls return ints. If *newvalue* is omitted, return the
+ current setting.
+
+ For compatibility with older Python versions, accessing :class:`stat_result` as
+ a tuple always returns integers.
+
+ .. versionchanged:: 2.5
+ Python now returns float values by default. Applications which do not work
+ correctly with floating point time stamps can use this function to restore the
+ old behaviour.
+
+ The resolution of the timestamps (that is the smallest possible fraction)
+ depends on the system. Some systems only support second resolution; on these
+ systems, the fraction will always be zero.
+
+ It is recommended that this setting is only changed at program startup time in
+ the *__main__* module; libraries should never change this setting. If an
+ application uses a library that works incorrectly if floating point time stamps
+ are processed, this application should turn the feature off until the library
+ has been corrected.
+
+
+.. function:: statvfs(path)
+
+ Perform a :cfunc:`statvfs` system call on the given path. The return value is
+ an object whose attributes describe the filesystem on the given path, and
+ correspond to the members of the :ctype:`statvfs` structure, namely:
+ :attr:`f_bsize`, :attr:`f_frsize`, :attr:`f_blocks`, :attr:`f_bfree`,
+ :attr:`f_bavail`, :attr:`f_files`, :attr:`f_ffree`, :attr:`f_favail`,
+ :attr:`f_flag`, :attr:`f_namemax`. Availability: Unix.
+
+ .. index:: module: statvfs
+
+ For backward compatibility, the return value is also accessible as a tuple whose
+ values correspond to the attributes, in the order given above. The standard
+ module :mod:`statvfs` defines constants that are useful for extracting
+ information from a :ctype:`statvfs` structure when accessing it as a sequence;
+ this remains useful when writing code that needs to work with versions of Python
+ that don't support accessing the fields as attributes.
+
+ .. versionchanged:: 2.2
+ Added access to values as attributes of the returned object.
+
+
+.. function:: symlink(src, dst)
+
+ Create a symbolic link pointing to *src* named *dst*. Availability: Unix.
+
+
+.. function:: tempnam([dir[, prefix]])
+
+ Return a unique path name that is reasonable for creating a temporary file.
+ This will be an absolute path that names a potential directory entry in the
+ directory *dir* or a common location for temporary files if *dir* is omitted or
+ ``None``. If given and not ``None``, *prefix* is used to provide a short prefix
+ to the filename. Applications are responsible for properly creating and
+ managing files created using paths returned by :func:`tempnam`; no automatic
+ cleanup is provided. On Unix, the environment variable :envvar:`TMPDIR`
+ overrides *dir*, while on Windows the :envvar:`TMP` is used. The specific
+ behavior of this function depends on the C library implementation; some aspects
+ are underspecified in system documentation.
+
+ .. warning::
+
+ Use of :func:`tempnam` is vulnerable to symlink attacks; consider using
+ :func:`tmpfile` (section :ref:`os-newstreams`) instead.
+
+ Availability: Macintosh, Unix, Windows.
+
+
+.. function:: tmpnam()
+
+ Return a unique path name that is reasonable for creating a temporary file.
+ This will be an absolute path that names a potential directory entry in a common
+ location for temporary files. Applications are responsible for properly
+ creating and managing files created using paths returned by :func:`tmpnam`; no
+ automatic cleanup is provided.
+
+ .. warning::
+
+ Use of :func:`tmpnam` is vulnerable to symlink attacks; consider using
+ :func:`tmpfile` (section :ref:`os-newstreams`) instead.
+
+ Availability: Unix, Windows. This function probably shouldn't be used on
+ Windows, though: Microsoft's implementation of :func:`tmpnam` always creates a
+ name in the root directory of the current drive, and that's generally a poor
+ location for a temp file (depending on privileges, you may not even be able to
+ open a file using this name).
+
+
+.. data:: TMP_MAX
+
+ The maximum number of unique names that :func:`tmpnam` will generate before
+ reusing names.
+
+
+.. function:: unlink(path)
+
+ Remove the file *path*. This is the same function as :func:`remove`; the
+ :func:`unlink` name is its traditional Unix name. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. function:: utime(path, times)
+
+ Set the access and modified times of the file specified by *path*. If *times* is
+ ``None``, then the file's access and modified times are set to the current time.
+ Otherwise, *times* must be a 2-tuple of numbers, of the form ``(atime, mtime)``
+ which is used to set the access and modified times, respectively. Whether a
+ directory can be given for *path* depends on whether the operating system
+ implements directories as files (for example, Windows does not). Note that the
+ exact times you set here may not be returned by a subsequent :func:`stat` call,
+ depending on the resolution with which your operating system records access and
+ modification times; see :func:`stat`.
+
+ .. versionchanged:: 2.0
+ Added support for ``None`` for *times*.
+
+ Availability: Macintosh, Unix, Windows.
+
+
+.. function:: walk(top[, topdown=True [, onerror=None[, followlinks=False]]])
+
+ .. index::
+ single: directory; walking
+ single: directory; traversal
+
+ :func:`walk` generates the file names in a directory tree, by walking the tree
+ either top down or bottom up. For each directory in the tree rooted at directory
+ *top* (including *top* itself), it yields a 3-tuple ``(dirpath, dirnames,
+ filenames)``.
+
+ *dirpath* is a string, the path to the directory. *dirnames* is a list of the
+ names of the subdirectories in *dirpath* (excluding ``'.'`` and ``'..'``).
+ *filenames* is a list of the names of the non-directory files in *dirpath*.
+ Note that the names in the lists contain no path components. To get a full path
+ (which begins with *top*) to a file or directory in *dirpath*, do
+ ``os.path.join(dirpath, name)``.
+
+ If optional argument *topdown* is true or not specified, the triple for a
+ directory is generated before the triples for any of its subdirectories
+ (directories are generated top down). If *topdown* is false, the triple for a
+ directory is generated after the triples for all of its subdirectories
+ (directories are generated bottom up).
+
+ When *topdown* is true, the caller can modify the *dirnames* list in-place
+ (perhaps using :keyword:`del` or slice assignment), and :func:`walk` will only
+ recurse into the subdirectories whose names remain in *dirnames*; this can be
+ used to prune the search, impose a specific order of visiting, or even to inform
+ :func:`walk` about directories the caller creates or renames before it resumes
+ :func:`walk` again. Modifying *dirnames* when *topdown* is false is
+ ineffective, because in bottom-up mode the directories in *dirnames* are
+ generated before *dirpath* itself is generated.
+
+ By default errors from the ``os.listdir()`` call are ignored. If optional
+ argument *onerror* is specified, it should be a function; it will be called with
+ one argument, an :exc:`OSError` instance. It can report the error to continue
+ with the walk, or raise the exception to abort the walk. Note that the filename
+ is available as the ``filename`` attribute of the exception object.
+
+ By default, :func:`walk` will not walk down into symbolic links that resolve to
+ directories. Set *followlinks* to True to visit directories pointed to by
+ symlinks, on systems that support them.
+
+ .. versionadded:: 2.6
+ The *followlinks* parameter.
+
+ .. note::
+
+ Be aware that setting *followlinks* to true can lead to infinite recursion if a
+ link points to a parent directory of itself. :func:`walk` does not keep track of
+ the directories it visited already.
+
+ .. note::
+
+ If you pass a relative pathname, don't change the current working directory
+ between resumptions of :func:`walk`. :func:`walk` never changes the current
+ directory, and assumes that its caller doesn't either.
+
+ This example displays the number of bytes taken by non-directory files in each
+ directory under the starting directory, except that it doesn't look under any
+ CVS subdirectory::
+
+ import os
+ from os.path import join, getsize
+ for root, dirs, files in os.walk('python/Lib/email'):
+ print root, "consumes",
+ print sum(getsize(join(root, name)) for name in files),
+ print "bytes in", len(files), "non-directory files"
+ if 'CVS' in dirs:
+ dirs.remove('CVS') # don't visit CVS directories
+
+ In the next example, walking the tree bottom up is essential: :func:`rmdir`
+ doesn't allow deleting a directory before the directory is empty::
+
+ # Delete everything reachable from the directory named in 'top',
+ # assuming there are no symbolic links.
+ # CAUTION: This is dangerous! For example, if top == '/', it
+ # could delete all your disk files.
+ import os
+ for root, dirs, files in os.walk(top, topdown=False):
+ for name in files:
+ os.remove(os.path.join(root, name))
+ for name in dirs:
+ os.rmdir(os.path.join(root, name))
+
+ .. versionadded:: 2.3
+
+
+.. _os-process:
+
+Process Management
+------------------
+
+These functions may be used to create and manage processes.
+
+The various :func:`exec\*` functions take a list of arguments for the new
+program loaded into the process. In each case, the first of these arguments is
+passed to the new program as its own name rather than as an argument a user may
+have typed on a command line. For the C programmer, this is the ``argv[0]``
+passed to a program's :cfunc:`main`. For example, ``os.execv('/bin/echo',
+['foo', 'bar'])`` will only print ``bar`` on standard output; ``foo`` will seem
+to be ignored.
+
+
+.. function:: abort()
+
+ Generate a :const:`SIGABRT` signal to the current process. On Unix, the default
+ behavior is to produce a core dump; on Windows, the process immediately returns
+ an exit code of ``3``. Be aware that programs which use :func:`signal.signal`
+ to register a handler for :const:`SIGABRT` will behave differently.
+ Availability: Macintosh, Unix, Windows.
+
+
+.. function:: execl(path, arg0, arg1, ...)
+ execle(path, arg0, arg1, ..., env)
+ execlp(file, arg0, arg1, ...)
+ execlpe(file, arg0, arg1, ..., env)
+ execv(path, args)
+ execve(path, args, env)
+ execvp(file, args)
+ execvpe(file, args, env)
+
+ These functions all execute a new program, replacing the current process; they
+ do not return. On Unix, the new executable is loaded into the current process,
+ and will have the same process ID as the caller. Errors will be reported as
+ :exc:`OSError` exceptions.
+
+ The ``'l'`` and ``'v'`` variants of the :func:`exec\*` functions differ in how
+ command-line arguments are passed. The ``'l'`` variants are perhaps the easiest
+ to work with if the number of parameters is fixed when the code is written; the
+ individual parameters simply become additional parameters to the :func:`execl\*`
+ functions. The ``'v'`` variants are good when the number of parameters is
+ variable, with the arguments being passed in a list or tuple as the *args*
+ parameter. In either case, the arguments to the child process should start with
+ the name of the command being run, but this is not enforced.
+
+ The variants which include a ``'p'`` near the end (:func:`execlp`,
+ :func:`execlpe`, :func:`execvp`, and :func:`execvpe`) will use the
+ :envvar:`PATH` environment variable to locate the program *file*. When the
+ environment is being replaced (using one of the :func:`exec\*e` variants,
+ discussed in the next paragraph), the new environment is used as the source of
+ the :envvar:`PATH` variable. The other variants, :func:`execl`, :func:`execle`,
+ :func:`execv`, and :func:`execve`, will not use the :envvar:`PATH` variable to
+ locate the executable; *path* must contain an appropriate absolute or relative
+ path.
+
+ For :func:`execle`, :func:`execlpe`, :func:`execve`, and :func:`execvpe` (note
+ that these all end in ``'e'``), the *env* parameter must be a mapping which is
+ used to define the environment variables for the new process; the :func:`execl`,
+ :func:`execlp`, :func:`execv`, and :func:`execvp` all cause the new process to
+ inherit the environment of the current process. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. function:: _exit(n)
+
+ Exit to the system with status *n*, without calling cleanup handlers, flushing
+ stdio buffers, etc. Availability: Macintosh, Unix, Windows.
+
+ .. note::
+
+ The standard way to exit is ``sys.exit(n)``. :func:`_exit` should normally only
+ be used in the child process after a :func:`fork`.
+
+The following exit codes are a defined, and can be used with :func:`_exit`,
+although they are not required. These are typically used for system programs
+written in Python, such as a mail server's external command delivery program.
+
+.. note::
+
+ Some of these may not be available on all Unix platforms, since there is some
+ variation. These constants are defined where they are defined by the underlying
+ platform.
+
+
+.. data:: EX_OK
+
+ Exit code that means no error occurred. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_USAGE
+
+ Exit code that means the command was used incorrectly, such as when the wrong
+ number of arguments are given. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_DATAERR
+
+ Exit code that means the input data was incorrect. Availability: Macintosh,
+ Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_NOINPUT
+
+ Exit code that means an input file did not exist or was not readable.
+ Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_NOUSER
+
+ Exit code that means a specified user did not exist. Availability: Macintosh,
+ Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_NOHOST
+
+ Exit code that means a specified host did not exist. Availability: Macintosh,
+ Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_UNAVAILABLE
+
+ Exit code that means that a required service is unavailable. Availability:
+ Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_SOFTWARE
+
+ Exit code that means an internal software error was detected. Availability:
+ Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_OSERR
+
+ Exit code that means an operating system error was detected, such as the
+ inability to fork or create a pipe. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_OSFILE
+
+ Exit code that means some system file did not exist, could not be opened, or had
+ some other kind of error. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_CANTCREAT
+
+ Exit code that means a user specified output file could not be created.
+ Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_IOERR
+
+ Exit code that means that an error occurred while doing I/O on some file.
+ Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_TEMPFAIL
+
+ Exit code that means a temporary failure occurred. This indicates something
+ that may not really be an error, such as a network connection that couldn't be
+ made during a retryable operation. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_PROTOCOL
+
+ Exit code that means that a protocol exchange was illegal, invalid, or not
+ understood. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_NOPERM
+
+ Exit code that means that there were insufficient permissions to perform the
+ operation (but not intended for file system problems). Availability: Macintosh,
+ Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_CONFIG
+
+ Exit code that means that some kind of configuration error occurred.
+ Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. data:: EX_NOTFOUND
+
+ Exit code that means something like "an entry was not found". Availability:
+ Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: fork()
+
+ Fork a child process. Return ``0`` in the child, the child's process id in the
+ parent. Availability: Macintosh, Unix.
+
+
+.. function:: forkpty()
+
+ Fork a child process, using a new pseudo-terminal as the child's controlling
+ terminal. Return a pair of ``(pid, fd)``, where *pid* is ``0`` in the child, the
+ new child's process id in the parent, and *fd* is the file descriptor of the
+ master end of the pseudo-terminal. For a more portable approach, use the
+ :mod:`pty` module. Availability: Macintosh, Some flavors of Unix.
+
+
+.. function:: kill(pid, sig)
+
+ .. index::
+ single: process; killing
+ single: process; signalling
+
+ Send signal *sig* to the process *pid*. Constants for the specific signals
+ available on the host platform are defined in the :mod:`signal` module.
+ Availability: Macintosh, Unix.
+
+
+.. function:: killpg(pgid, sig)
+
+ .. index::
+ single: process; killing
+ single: process; signalling
+
+ Send the signal *sig* to the process group *pgid*. Availability: Macintosh,
+ Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: nice(increment)
+
+ Add *increment* to the process's "niceness". Return the new niceness.
+ Availability: Macintosh, Unix.
+
+
+.. function:: plock(op)
+
+ Lock program segments into memory. The value of *op* (defined in
+ ``<sys/lock.h>``) determines which segments are locked. Availability: Macintosh,
+ Unix.
+
+
+.. function:: popen(...)
+ :noindex:
+
+ Run child processes, returning opened pipes for communications. These functions
+ are described in section :ref:`os-newstreams`.
+
+
+.. function:: spawnl(mode, path, ...)
+ spawnle(mode, path, ..., env)
+ spawnlp(mode, file, ...)
+ spawnlpe(mode, file, ..., env)
+ spawnv(mode, path, args)
+ spawnve(mode, path, args, env)
+ spawnvp(mode, file, args)
+ spawnvpe(mode, file, args, env)
+
+ Execute the program *path* in a new process.
+
+ (Note that the :mod:`subprocess` module provides more powerful facilities for
+ spawning new processes and retrieving their results; using that module is
+ preferable to using these functions.)
+
+ If *mode* is :const:`P_NOWAIT`, this function returns the process ID of the new
+ process; if *mode* is :const:`P_WAIT`, returns the process's exit code if it
+ exits normally, or ``-signal``, where *signal* is the signal that killed the
+ process. On Windows, the process ID will actually be the process handle, so can
+ be used with the :func:`waitpid` function.
+
+ The ``'l'`` and ``'v'`` variants of the :func:`spawn\*` functions differ in how
+ command-line arguments are passed. The ``'l'`` variants are perhaps the easiest
+ to work with if the number of parameters is fixed when the code is written; the
+ individual parameters simply become additional parameters to the
+ :func:`spawnl\*` functions. The ``'v'`` variants are good when the number of
+ parameters is variable, with the arguments being passed in a list or tuple as
+ the *args* parameter. In either case, the arguments to the child process must
+ start with the name of the command being run.
+
+ The variants which include a second ``'p'`` near the end (:func:`spawnlp`,
+ :func:`spawnlpe`, :func:`spawnvp`, and :func:`spawnvpe`) will use the
+ :envvar:`PATH` environment variable to locate the program *file*. When the
+ environment is being replaced (using one of the :func:`spawn\*e` variants,
+ discussed in the next paragraph), the new environment is used as the source of
+ the :envvar:`PATH` variable. The other variants, :func:`spawnl`,
+ :func:`spawnle`, :func:`spawnv`, and :func:`spawnve`, will not use the
+ :envvar:`PATH` variable to locate the executable; *path* must contain an
+ appropriate absolute or relative path.
+
+ For :func:`spawnle`, :func:`spawnlpe`, :func:`spawnve`, and :func:`spawnvpe`
+ (note that these all end in ``'e'``), the *env* parameter must be a mapping
+ which is used to define the environment variables for the new process; the
+ :func:`spawnl`, :func:`spawnlp`, :func:`spawnv`, and :func:`spawnvp` all cause
+ the new process to inherit the environment of the current process.
+
+ As an example, the following calls to :func:`spawnlp` and :func:`spawnvpe` are
+ equivalent::
+
+ import os
+ os.spawnlp(os.P_WAIT, 'cp', 'cp', 'index.html', '/dev/null')
+
+ L = ['cp', 'index.html', '/dev/null']
+ os.spawnvpe(os.P_WAIT, 'cp', L, os.environ)
+
+ Availability: Unix, Windows. :func:`spawnlp`, :func:`spawnlpe`, :func:`spawnvp`
+ and :func:`spawnvpe` are not available on Windows.
+
+ .. versionadded:: 1.6
+
+
+.. data:: P_NOWAIT
+ P_NOWAITO
+
+ Possible values for the *mode* parameter to the :func:`spawn\*` family of
+ functions. If either of these values is given, the :func:`spawn\*` functions
+ will return as soon as the new process has been created, with the process ID as
+ the return value. Availability: Macintosh, Unix, Windows.
+
+ .. versionadded:: 1.6
+
+
+.. data:: P_WAIT
+
+ Possible value for the *mode* parameter to the :func:`spawn\*` family of
+ functions. If this is given as *mode*, the :func:`spawn\*` functions will not
+ return until the new process has run to completion and will return the exit code
+ of the process the run is successful, or ``-signal`` if a signal kills the
+ process. Availability: Macintosh, Unix, Windows.
+
+ .. versionadded:: 1.6
+
+
+.. data:: P_DETACH
+ P_OVERLAY
+
+ Possible values for the *mode* parameter to the :func:`spawn\*` family of
+ functions. These are less portable than those listed above. :const:`P_DETACH`
+ is similar to :const:`P_NOWAIT`, but the new process is detached from the
+ console of the calling process. If :const:`P_OVERLAY` is used, the current
+ process will be replaced; the :func:`spawn\*` function will not return.
+ Availability: Windows.
+
+ .. versionadded:: 1.6
+
+
+.. function:: startfile(path[, operation])
+
+ Start a file with its associated application.
+
+ When *operation* is not specified or ``'open'``, this acts like double-clicking
+ the file in Windows Explorer, or giving the file name as an argument to the
+ :program:`start` command from the interactive command shell: the file is opened
+ with whatever application (if any) its extension is associated.
+
+ When another *operation* is given, it must be a "command verb" that specifies
+ what should be done with the file. Common verbs documented by Microsoft are
+ ``'print'`` and ``'edit'`` (to be used on files) as well as ``'explore'`` and
+ ``'find'`` (to be used on directories).
+
+ :func:`startfile` returns as soon as the associated application is launched.
+ There is no option to wait for the application to close, and no way to retrieve
+ the application's exit status. The *path* parameter is relative to the current
+ directory. If you want to use an absolute path, make sure the first character
+ is not a slash (``'/'``); the underlying Win32 :cfunc:`ShellExecute` function
+ doesn't work if it is. Use the :func:`os.path.normpath` function to ensure that
+ the path is properly encoded for Win32. Availability: Windows.
+
+ .. versionadded:: 2.0
+
+ .. versionadded:: 2.5
+ The *operation* parameter.
+
+
+.. function:: system(command)
+
+ Execute the command (a string) in a subshell. This is implemented by calling
+ the Standard C function :cfunc:`system`, and has the same limitations. Changes
+ to ``posix.environ``, ``sys.stdin``, etc. are not reflected in the environment
+ of the executed command.
+
+ On Unix, the return value is the exit status of the process encoded in the
+ format specified for :func:`wait`. Note that POSIX does not specify the meaning
+ of the return value of the C :cfunc:`system` function, so the return value of
+ the Python function is system-dependent.
+
+ On Windows, the return value is that returned by the system shell after running
+ *command*, given by the Windows environment variable :envvar:`COMSPEC`: on
+ :program:`command.com` systems (Windows 95, 98 and ME) this is always ``0``; on
+ :program:`cmd.exe` systems (Windows NT, 2000 and XP) this is the exit status of
+ the command run; on systems using a non-native shell, consult your shell
+ documentation.
+
+ Availability: Macintosh, Unix, Windows.
+
+ The :mod:`subprocess` module provides more powerful facilities for spawning new
+ processes and retrieving their results; using that module is preferable to using
+ this function.
+
+
+.. function:: times()
+
+ Return a 5-tuple of floating point numbers indicating accumulated (processor or
+ other) times, in seconds. The items are: user time, system time, children's
+ user time, children's system time, and elapsed real time since a fixed point in
+ the past, in that order. See the Unix manual page :manpage:`times(2)` or the
+ corresponding Windows Platform API documentation. Availability: Macintosh, Unix,
+ Windows.
+
+
+.. function:: wait()
+
+ Wait for completion of a child process, and return a tuple containing its pid
+ and exit status indication: a 16-bit number, whose low byte is the signal number
+ that killed the process, and whose high byte is the exit status (if the signal
+ number is zero); the high bit of the low byte is set if a core file was
+ produced. Availability: Macintosh, Unix.
+
+
+.. function:: waitpid(pid, options)
+
+ The details of this function differ on Unix and Windows.
+
+ On Unix: Wait for completion of a child process given by process id *pid*, and
+ return a tuple containing its process id and exit status indication (encoded as
+ for :func:`wait`). The semantics of the call are affected by the value of the
+ integer *options*, which should be ``0`` for normal operation.
+
+ If *pid* is greater than ``0``, :func:`waitpid` requests status information for
+ that specific process. If *pid* is ``0``, the request is for the status of any
+ child in the process group of the current process. If *pid* is ``-1``, the
+ request pertains to any child of the current process. If *pid* is less than
+ ``-1``, status is requested for any process in the process group ``-pid`` (the
+ absolute value of *pid*).
+
+ On Windows: Wait for completion of a process given by process handle *pid*, and
+ return a tuple containing *pid*, and its exit status shifted left by 8 bits
+ (shifting makes cross-platform use of the function easier). A *pid* less than or
+ equal to ``0`` has no special meaning on Windows, and raises an exception. The
+ value of integer *options* has no effect. *pid* can refer to any process whose
+ id is known, not necessarily a child process. The :func:`spawn` functions called
+ with :const:`P_NOWAIT` return suitable process handles.
+
+
+.. function:: wait3([options])
+
+ Similar to :func:`waitpid`, except no process id argument is given and a
+ 3-element tuple containing the child's process id, exit status indication, and
+ resource usage information is returned. Refer to :mod:`resource`.\
+ :func:`getrusage` for details on resource usage information. The option
+ argument is the same as that provided to :func:`waitpid` and :func:`wait4`.
+ Availability: Unix.
+
+ .. versionadded:: 2.5
+
+
+.. function:: wait4(pid, options)
+
+ Similar to :func:`waitpid`, except a 3-element tuple, containing the child's
+ process id, exit status indication, and resource usage information is returned.
+ Refer to :mod:`resource`.\ :func:`getrusage` for details on resource usage
+ information. The arguments to :func:`wait4` are the same as those provided to
+ :func:`waitpid`. Availability: Unix.
+
+ .. versionadded:: 2.5
+
+
+.. data:: WNOHANG
+
+ The option for :func:`waitpid` to return immediately if no child process status
+ is available immediately. The function returns ``(0, 0)`` in this case.
+ Availability: Macintosh, Unix.
+
+
+.. data:: WCONTINUED
+
+ This option causes child processes to be reported if they have been continued
+ from a job control stop since their status was last reported. Availability: Some
+ Unix systems.
+
+ .. versionadded:: 2.3
+
+
+.. data:: WUNTRACED
+
+ This option causes child processes to be reported if they have been stopped but
+ their current state has not been reported since they were stopped. Availability:
+ Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+The following functions take a process status code as returned by
+:func:`system`, :func:`wait`, or :func:`waitpid` as a parameter. They may be
+used to determine the disposition of a process.
+
+
+.. function:: WCOREDUMP(status)
+
+ Returns ``True`` if a core dump was generated for the process, otherwise it
+ returns ``False``. Availability: Macintosh, Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: WIFCONTINUED(status)
+
+ Returns ``True`` if the process has been continued from a job control stop,
+ otherwise it returns ``False``. Availability: Unix.
+
+ .. versionadded:: 2.3
+
+
+.. function:: WIFSTOPPED(status)
+
+ Returns ``True`` if the process has been stopped, otherwise it returns
+ ``False``. Availability: Unix.
+
+
+.. function:: WIFSIGNALED(status)
+
+ Returns ``True`` if the process exited due to a signal, otherwise it returns
+ ``False``. Availability: Macintosh, Unix.
+
+
+.. function:: WIFEXITED(status)
+
+ Returns ``True`` if the process exited using the :manpage:`exit(2)` system call,
+ otherwise it returns ``False``. Availability: Macintosh, Unix.
+
+
+.. function:: WEXITSTATUS(status)
+
+ If ``WIFEXITED(status)`` is true, return the integer parameter to the
+ :manpage:`exit(2)` system call. Otherwise, the return value is meaningless.
+ Availability: Macintosh, Unix.
+
+
+.. function:: WSTOPSIG(status)
+
+ Return the signal which caused the process to stop. Availability: Macintosh,
+ Unix.
+
+
+.. function:: WTERMSIG(status)
+
+ Return the signal which caused the process to exit. Availability: Macintosh,
+ Unix.
+
+
+.. _os-path:
+
+Miscellaneous System Information
+--------------------------------
+
+
+.. function:: confstr(name)
+
+ Return string-valued system configuration values. *name* specifies the
+ configuration value to retrieve; it may be a string which is the name of a
+ defined system value; these names are specified in a number of standards (POSIX,
+ Unix 95, Unix 98, and others). Some platforms define additional names as well.
+ The names known to the host operating system are given as the keys of the
+ ``confstr_names`` dictionary. For configuration variables not included in that
+ mapping, passing an integer for *name* is also accepted. Availability:
+ Macintosh, Unix.
+
+ If the configuration value specified by *name* isn't defined, ``None`` is
+ returned.
+
+ If *name* is a string and is not known, :exc:`ValueError` is raised. If a
+ specific value for *name* is not supported by the host system, even if it is
+ included in ``confstr_names``, an :exc:`OSError` is raised with
+ :const:`errno.EINVAL` for the error number.
+
+
+.. data:: confstr_names
+
+ Dictionary mapping names accepted by :func:`confstr` to the integer values
+ defined for those names by the host operating system. This can be used to
+ determine the set of names known to the system. Availability: Macintosh, Unix.
+
+
+.. function:: getloadavg()
+
+ Return the number of processes in the system run queue averaged over the last 1,
+ 5, and 15 minutes or raises :exc:`OSError` if the load average was
+ unobtainable.
+
+ .. versionadded:: 2.3
+
+
+.. function:: sysconf(name)
+
+ Return integer-valued system configuration values. If the configuration value
+ specified by *name* isn't defined, ``-1`` is returned. The comments regarding
+ the *name* parameter for :func:`confstr` apply here as well; the dictionary that
+ provides information on the known names is given by ``sysconf_names``.
+ Availability: Macintosh, Unix.
+
+
+.. data:: sysconf_names
+
+ Dictionary mapping names accepted by :func:`sysconf` to the integer values
+ defined for those names by the host operating system. This can be used to
+ determine the set of names known to the system. Availability: Macintosh, Unix.
+
+The follow data values are used to support path manipulation operations. These
+are defined for all platforms.
+
+Higher-level operations on pathnames are defined in the :mod:`os.path` module.
+
+
+.. data:: curdir
+
+ The constant string used by the operating system to refer to the current
+ directory. For example: ``'.'`` for POSIX or ``':'`` for Mac OS 9. Also
+ available via :mod:`os.path`.
+
+
+.. data:: pardir
+
+ The constant string used by the operating system to refer to the parent
+ directory. For example: ``'..'`` for POSIX or ``'::'`` for Mac OS 9. Also
+ available via :mod:`os.path`.
+
+
+.. data:: sep
+
+ The character used by the operating system to separate pathname components, for
+ example, ``'/'`` for POSIX or ``':'`` for Mac OS 9. Note that knowing this is
+ not sufficient to be able to parse or concatenate pathnames --- use
+ :func:`os.path.split` and :func:`os.path.join` --- but it is occasionally
+ useful. Also available via :mod:`os.path`.
+
+
+.. data:: altsep
+
+ An alternative character used by the operating system to separate pathname
+ components, or ``None`` if only one separator character exists. This is set to
+ ``'/'`` on Windows systems where ``sep`` is a backslash. Also available via
+ :mod:`os.path`.
+
+
+.. data:: extsep
+
+ The character which separates the base filename from the extension; for example,
+ the ``'.'`` in :file:`os.py`. Also available via :mod:`os.path`.
+
+ .. versionadded:: 2.2
+
+
+.. data:: pathsep
+
+ The character conventionally used by the operating system to separate search
+ path components (as in :envvar:`PATH`), such as ``':'`` for POSIX or ``';'`` for
+ Windows. Also available via :mod:`os.path`.
+
+
+.. data:: defpath
+
+ The default search path used by :func:`exec\*p\*` and :func:`spawn\*p\*` if the
+ environment doesn't have a ``'PATH'`` key. Also available via :mod:`os.path`.
+
+
+.. data:: linesep
+
+ The string used to separate (or, rather, terminate) lines on the current
+ platform. This may be a single character, such as ``'\n'`` for POSIX or
+ ``'\r'`` for Mac OS, or multiple characters, for example, ``'\r\n'`` for
+ Windows. Do not use *os.linesep* as a line terminator when writing files opened
+ in text mode (the default); use a single ``'\n'`` instead, on all platforms.
+
+
+.. data:: devnull
+
+ The file path of the null device. For example: ``'/dev/null'`` for POSIX or
+ ``'Dev:Nul'`` for Mac OS 9. Also available via :mod:`os.path`.
+
+ .. versionadded:: 2.4
+
+
+.. _os-miscfunc:
+
+Miscellaneous Functions
+-----------------------
+
+
+.. function:: urandom(n)
+
+ Return a string of *n* random bytes suitable for cryptographic use.
+
+ This function returns random bytes from an OS-specific randomness source. The
+ returned data should be unpredictable enough for cryptographic applications,
+ though its exact quality depends on the OS implementation. On a UNIX-like
+ system this will query /dev/urandom, and on Windows it will use CryptGenRandom.
+ If a randomness source is not found, :exc:`NotImplementedError` will be raised.
+
+ .. versionadded:: 2.4
+
diff --git a/Doc/library/ossaudiodev.rst b/Doc/library/ossaudiodev.rst
new file mode 100644
index 0000000000..066b26bca2
--- /dev/null
+++ b/Doc/library/ossaudiodev.rst
@@ -0,0 +1,429 @@
+
+:mod:`ossaudiodev` --- Access to OSS-compatible audio devices
+=============================================================
+
+.. module:: ossaudiodev
+ :platform: Linux, FreeBSD
+ :synopsis: Access to OSS-compatible audio devices.
+
+
+.. versionadded:: 2.3
+
+This module allows you to access the OSS (Open Sound System) audio interface.
+OSS is available for a wide range of open-source and commercial Unices, and is
+the standard audio interface for Linux and recent versions of FreeBSD.
+
+.. % Things will get more complicated for future Linux versions, since
+.. % ALSA is in the standard kernel as of 2.5.x. Presumably if you
+.. % use ALSA, you'll have to make sure its OSS compatibility layer
+.. % is active to use ossaudiodev, but you're gonna need it for the vast
+.. % majority of Linux audio apps anyways.
+.. %
+.. % Sounds like things are also complicated for other BSDs. In response
+.. % to my python-dev query, Thomas Wouters said:
+.. %
+.. % > Likewise, googling shows OpenBSD also uses OSS/Free -- the commercial
+.. % > OSS installation manual tells you to remove references to OSS/Free from the
+.. % > kernel :)
+.. %
+.. % but Aleksander Piotrowsk actually has an OpenBSD box, and he quotes
+.. % from its <soundcard.h>:
+.. % > * WARNING! WARNING!
+.. % > * This is an OSS (Linux) audio emulator.
+.. % > * Use the Native NetBSD API for developing new code, and this
+.. % > * only for compiling Linux programs.
+.. %
+.. % There's also an ossaudio manpage on OpenBSD that explains things
+.. % further. Presumably NetBSD and OpenBSD have a different standard
+.. % audio interface. That's the great thing about standards, there are so
+.. % many to choose from ... ;-)
+.. %
+.. % This probably all warrants a footnote or two, but I don't understand
+.. % things well enough right now to write it! --GPW
+
+
+.. seealso::
+
+ `Open Sound System Programmer's Guide <http://www.opensound.com/pguide/oss.pdf>`_
+ the official documentation for the OSS C API
+
+ The module defines a large number of constants supplied by the OSS device
+ driver; see ``<sys/soundcard.h>`` on either Linux or FreeBSD for a listing .
+
+:mod:`ossaudiodev` defines the following variables and functions:
+
+
+.. exception:: OSSAudioError
+
+ This exception is raised on certain errors. The argument is a string describing
+ what went wrong.
+
+ (If :mod:`ossaudiodev` receives an error from a system call such as
+ :cfunc:`open`, :cfunc:`write`, or :cfunc:`ioctl`, it raises :exc:`IOError`.
+ Errors detected directly by :mod:`ossaudiodev` result in :exc:`OSSAudioError`.)
+
+ (For backwards compatibility, the exception class is also available as
+ ``ossaudiodev.error``.)
+
+
+.. function:: open([device, ]mode)
+
+ Open an audio device and return an OSS audio device object. This object
+ supports many file-like methods, such as :meth:`read`, :meth:`write`, and
+ :meth:`fileno` (although there are subtle differences between conventional Unix
+ read/write semantics and those of OSS audio devices). It also supports a number
+ of audio-specific methods; see below for the complete list of methods.
+
+ *device* is the audio device filename to use. If it is not specified, this
+ module first looks in the environment variable :envvar:`AUDIODEV` for a device
+ to use. If not found, it falls back to :file:`/dev/dsp`.
+
+ *mode* is one of ``'r'`` for read-only (record) access, ``'w'`` for
+ write-only (playback) access and ``'rw'`` for both. Since many sound cards
+ only allow one process to have the recorder or player open at a time, it is a
+ good idea to open the device only for the activity needed. Further, some
+ sound cards are half-duplex: they can be opened for reading or writing, but
+ not both at once.
+
+ Note the unusual calling syntax: the *first* argument is optional, and the
+ second is required. This is a historical artifact for compatibility with the
+ older :mod:`linuxaudiodev` module which :mod:`ossaudiodev` supersedes.
+
+ .. % XXX it might also be motivated
+ .. % by my unfounded-but-still-possibly-true belief that the default
+ .. % audio device varies unpredictably across operating systems. -GW
+
+
+.. function:: openmixer([device])
+
+ Open a mixer device and return an OSS mixer device object. *device* is the
+ mixer device filename to use. If it is not specified, this module first looks
+ in the environment variable :envvar:`MIXERDEV` for a device to use. If not
+ found, it falls back to :file:`/dev/mixer`.
+
+
+.. _ossaudio-device-objects:
+
+Audio Device Objects
+--------------------
+
+Before you can write to or read from an audio device, you must call three
+methods in the correct order:
+
+#. :meth:`setfmt` to set the output format
+
+#. :meth:`channels` to set the number of channels
+
+#. :meth:`speed` to set the sample rate
+
+Alternately, you can use the :meth:`setparameters` method to set all three audio
+parameters at once. This is more convenient, but may not be as flexible in all
+cases.
+
+The audio device objects returned by :func:`open` define the following methods
+and (read-only) attributes:
+
+
+.. method:: oss_audio_device.close()
+
+ Explicitly close the audio device. When you are done writing to or reading from
+ an audio device, you should explicitly close it. A closed device cannot be used
+ again.
+
+
+.. method:: oss_audio_device.fileno()
+
+ Return the file descriptor associated with the device.
+
+
+.. method:: oss_audio_device.read(size)
+
+ Read *size* bytes from the audio input and return them as a Python string.
+ Unlike most Unix device drivers, OSS audio devices in blocking mode (the
+ default) will block :func:`read` until the entire requested amount of data is
+ available.
+
+
+.. method:: oss_audio_device.write(data)
+
+ Write the Python string *data* to the audio device and return the number of
+ bytes written. If the audio device is in blocking mode (the default), the
+ entire string is always written (again, this is different from usual Unix device
+ semantics). If the device is in non-blocking mode, some data may not be written
+ ---see :meth:`writeall`.
+
+
+.. method:: oss_audio_device.writeall(data)
+
+ Write the entire Python string *data* to the audio device: waits until the audio
+ device is able to accept data, writes as much data as it will accept, and
+ repeats until *data* has been completely written. If the device is in blocking
+ mode (the default), this has the same effect as :meth:`write`; :meth:`writeall`
+ is only useful in non-blocking mode. Has no return value, since the amount of
+ data written is always equal to the amount of data supplied.
+
+The following methods each map to exactly one :func:`ioctl` system call. The
+correspondence is obvious: for example, :meth:`setfmt` corresponds to the
+``SNDCTL_DSP_SETFMT`` ioctl, and :meth:`sync` to ``SNDCTL_DSP_SYNC`` (this can
+be useful when consulting the OSS documentation). If the underlying
+:func:`ioctl` fails, they all raise :exc:`IOError`.
+
+
+.. method:: oss_audio_device.nonblock()
+
+ Put the device into non-blocking mode. Once in non-blocking mode, there is no
+ way to return it to blocking mode.
+
+
+.. method:: oss_audio_device.getfmts()
+
+ Return a bitmask of the audio output formats supported by the soundcard. Some
+ of the formats supported by OSS are:
+
+ +-------------------------+---------------------------------------------+
+ | Format | Description |
+ +=========================+=============================================+
+ | :const:`AFMT_MU_LAW` | a logarithmic encoding (used by Sun ``.au`` |
+ | | files and :file:`/dev/audio`) |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_A_LAW` | a logarithmic encoding |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_IMA_ADPCM` | a 4:1 compressed format defined by the |
+ | | Interactive Multimedia Association |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_U8` | Unsigned, 8-bit audio |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_S16_LE` | Signed, 16-bit audio, little-endian byte |
+ | | order (as used by Intel processors) |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_S16_BE` | Signed, 16-bit audio, big-endian byte order |
+ | | (as used by 68k, PowerPC, Sparc) |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_S8` | Signed, 8 bit audio |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_U16_LE` | Unsigned, 16-bit little-endian audio |
+ +-------------------------+---------------------------------------------+
+ | :const:`AFMT_U16_BE` | Unsigned, 16-bit big-endian audio |
+ +-------------------------+---------------------------------------------+
+
+ Consult the OSS documentation for a full list of audio formats, and note that
+ most devices support only a subset of these formats. Some older devices only
+ support :const:`AFMT_U8`; the most common format used today is
+ :const:`AFMT_S16_LE`.
+
+
+.. method:: oss_audio_device.setfmt(format)
+
+ Try to set the current audio format to *format*---see :meth:`getfmts` for a
+ list. Returns the audio format that the device was set to, which may not be the
+ requested format. May also be used to return the current audio format---do this
+ by passing an "audio format" of :const:`AFMT_QUERY`.
+
+
+.. method:: oss_audio_device.channels(nchannels)
+
+ Set the number of output channels to *nchannels*. A value of 1 indicates
+ monophonic sound, 2 stereophonic. Some devices may have more than 2 channels,
+ and some high-end devices may not support mono. Returns the number of channels
+ the device was set to.
+
+
+.. method:: oss_audio_device.speed(samplerate)
+
+ Try to set the audio sampling rate to *samplerate* samples per second. Returns
+ the rate actually set. Most sound devices don't support arbitrary sampling
+ rates. Common rates are:
+
+ +-------+-------------------------------------------+
+ | Rate | Description |
+ +=======+===========================================+
+ | 8000 | default rate for :file:`/dev/audio` |
+ +-------+-------------------------------------------+
+ | 11025 | speech recording |
+ +-------+-------------------------------------------+
+ | 22050 | |
+ +-------+-------------------------------------------+
+ | 44100 | CD quality audio (at 16 bits/sample and 2 |
+ | | channels) |
+ +-------+-------------------------------------------+
+ | 96000 | DVD quality audio (at 24 bits/sample) |
+ +-------+-------------------------------------------+
+
+
+.. method:: oss_audio_device.sync()
+
+ Wait until the sound device has played every byte in its buffer. (This happens
+ implicitly when the device is closed.) The OSS documentation recommends closing
+ and re-opening the device rather than using :meth:`sync`.
+
+
+.. method:: oss_audio_device.reset()
+
+ Immediately stop playing or recording and return the device to a state where it
+ can accept commands. The OSS documentation recommends closing and re-opening
+ the device after calling :meth:`reset`.
+
+
+.. method:: oss_audio_device.post()
+
+ Tell the driver that there is likely to be a pause in the output, making it
+ possible for the device to handle the pause more intelligently. You might use
+ this after playing a spot sound effect, before waiting for user input, or before
+ doing disk I/O.
+
+The following convenience methods combine several ioctls, or one ioctl and some
+simple calculations.
+
+
+.. method:: oss_audio_device.setparameters(format, nchannels, samplerate [, strict=False])
+
+ Set the key audio sampling parameters---sample format, number of channels, and
+ sampling rate---in one method call. *format*, *nchannels*, and *samplerate*
+ should be as specified in the :meth:`setfmt`, :meth:`channels`, and
+ :meth:`speed` methods. If *strict* is true, :meth:`setparameters` checks to
+ see if each parameter was actually set to the requested value, and raises
+ :exc:`OSSAudioError` if not. Returns a tuple (*format*, *nchannels*,
+ *samplerate*) indicating the parameter values that were actually set by the
+ device driver (i.e., the same as the return values of :meth:`setfmt`,
+ :meth:`channels`, and :meth:`speed`).
+
+ For example, ::
+
+ (fmt, channels, rate) = dsp.setparameters(fmt, channels, rate)
+
+ is equivalent to ::
+
+ fmt = dsp.setfmt(fmt)
+ channels = dsp.channels(channels)
+ rate = dsp.rate(channels)
+
+
+.. method:: oss_audio_device.bufsize()
+
+ Returns the size of the hardware buffer, in samples.
+
+
+.. method:: oss_audio_device.obufcount()
+
+ Returns the number of samples that are in the hardware buffer yet to be played.
+
+
+.. method:: oss_audio_device.obuffree()
+
+ Returns the number of samples that could be queued into the hardware buffer to
+ be played without blocking.
+
+Audio device objects also support several read-only attributes:
+
+
+.. attribute:: oss_audio_device.closed
+
+ Boolean indicating whether the device has been closed.
+
+
+.. attribute:: oss_audio_device.name
+
+ String containing the name of the device file.
+
+
+.. attribute:: oss_audio_device.mode
+
+ The I/O mode for the file, either ``"r"``, ``"rw"``, or ``"w"``.
+
+
+.. _mixer-device-objects:
+
+Mixer Device Objects
+--------------------
+
+The mixer object provides two file-like methods:
+
+
+.. method:: oss_mixer_device.close()
+
+ This method closes the open mixer device file. Any further attempts to use the
+ mixer after this file is closed will raise an :exc:`IOError`.
+
+
+.. method:: oss_mixer_device.fileno()
+
+ Returns the file handle number of the open mixer device file.
+
+The remaining methods are specific to audio mixing:
+
+
+.. method:: oss_mixer_device.controls()
+
+ This method returns a bitmask specifying the available mixer controls ("Control"
+ being a specific mixable "channel", such as :const:`SOUND_MIXER_PCM` or
+ :const:`SOUND_MIXER_SYNTH`). This bitmask indicates a subset of all available
+ mixer controls---the :const:`SOUND_MIXER_\*` constants defined at module level.
+ To determine if, for example, the current mixer object supports a PCM mixer, use
+ the following Python code::
+
+ mixer=ossaudiodev.openmixer()
+ if mixer.controls() & (1 << ossaudiodev.SOUND_MIXER_PCM):
+ # PCM is supported
+ ... code ...
+
+ For most purposes, the :const:`SOUND_MIXER_VOLUME` (master volume) and
+ :const:`SOUND_MIXER_PCM` controls should suffice---but code that uses the mixer
+ should be flexible when it comes to choosing mixer controls. On the Gravis
+ Ultrasound, for example, :const:`SOUND_MIXER_VOLUME` does not exist.
+
+
+.. method:: oss_mixer_device.stereocontrols()
+
+ Returns a bitmask indicating stereo mixer controls. If a bit is set, the
+ corresponding control is stereo; if it is unset, the control is either
+ monophonic or not supported by the mixer (use in combination with
+ :meth:`controls` to determine which).
+
+ See the code example for the :meth:`controls` function for an example of getting
+ data from a bitmask.
+
+
+.. method:: oss_mixer_device.reccontrols()
+
+ Returns a bitmask specifying the mixer controls that may be used to record. See
+ the code example for :meth:`controls` for an example of reading from a bitmask.
+
+
+.. method:: oss_mixer_device.get(control)
+
+ Returns the volume of a given mixer control. The returned volume is a 2-tuple
+ ``(left_volume,right_volume)``. Volumes are specified as numbers from 0
+ (silent) to 100 (full volume). If the control is monophonic, a 2-tuple is still
+ returned, but both volumes are the same.
+
+ Raises :exc:`OSSAudioError` if an invalid control was is specified, or
+ :exc:`IOError` if an unsupported control is specified.
+
+
+.. method:: oss_mixer_device.set(control, (left, right))
+
+ Sets the volume for a given mixer control to ``(left,right)``. ``left`` and
+ ``right`` must be ints and between 0 (silent) and 100 (full volume). On
+ success, the new volume is returned as a 2-tuple. Note that this may not be
+ exactly the same as the volume specified, because of the limited resolution of
+ some soundcard's mixers.
+
+ Raises :exc:`OSSAudioError` if an invalid mixer control was specified, or if the
+ specified volumes were out-of-range.
+
+
+.. method:: oss_mixer_device.get_recsrc()
+
+ This method returns a bitmask indicating which control(s) are currently being
+ used as a recording source.
+
+
+.. method:: oss_mixer_device.set_recsrc(bitmask)
+
+ Call this function to specify a recording source. Returns a bitmask indicating
+ the new recording source (or sources) if successful; raises :exc:`IOError` if an
+ invalid source was specified. To set the current recording source to the
+ microphone input::
+
+ mixer.setrecsrc (1 << ossaudiodev.SOUND_MIXER_MIC)
+
diff --git a/Doc/library/othergui.rst b/Doc/library/othergui.rst
new file mode 100644
index 0000000000..aadb74d773
--- /dev/null
+++ b/Doc/library/othergui.rst
@@ -0,0 +1,84 @@
+.. _other-gui-packages:
+
+Other Graphical User Interface Packages
+=======================================
+
+There are an number of extension widget sets to :mod:`Tkinter`.
+
+
+.. seealso::
+
+ `Python megawidgets <http://pmw.sourceforge.net/>`_
+ is a toolkit for building high-level compound widgets in Python using the
+ :mod:`Tkinter` module. It consists of a set of base classes and a library of
+ flexible and extensible megawidgets built on this foundation. These megawidgets
+ include notebooks, comboboxes, selection widgets, paned widgets, scrolled
+ widgets, dialog windows, etc. Also, with the Pmw.Blt interface to BLT, the
+ busy, graph, stripchart, tabset and vector commands are be available.
+
+ The initial ideas for Pmw were taken from the Tk ``itcl`` extensions ``[incr
+ Tk]`` by Michael McLennan and ``[incr Widgets]`` by Mark Ulferts. Several of the
+ megawidgets are direct translations from the itcl to Python. It offers most of
+ the range of widgets that ``[incr Widgets]`` does, and is almost as complete as
+ Tix, lacking however Tix's fast :class:`HList` widget for drawing trees.
+
+ `Tkinter3000 Widget Construction Kit (WCK) <http://tkinter.effbot.org/>`_
+ is a library that allows you to write new Tkinter widgets in pure Python. The
+ WCK framework gives you full control over widget creation, configuration, screen
+ appearance, and event handling. WCK widgets can be very fast and light-weight,
+ since they can operate directly on Python data structures, without having to
+ transfer data through the Tk/Tcl layer.
+
+ .. %
+
+The major cross-platform (Windows, Mac OS X, Unix-like) GUI toolkits that are
+also available for Python:
+
+
+.. seealso::
+
+ `PyGTK <http://www.pygtk.org/>`_
+ is a set of bindings for the `GTK <http://www.gtk.org/>`_ widget set. It
+ provides an object oriented interface that is slightly higher level than the C
+ one. It comes with many more widgets than Tkinter provides, and
+ has good Python-specific reference documentation. There are also `bindings
+ <http://www.daa.com.au/~james/gnome/>`_ to `GNOME <http://www.gnome.org>`_.
+ One well known PyGTK application is
+ `PythonCAD <http://www.pythoncad.org/>`_. An
+ online `tutorial <http://www.pygtk.org/pygtk2tutorial/index.html>`_ is
+ available.
+
+ `PyQt <//http://www.riverbankcomputing.co.uk/pyqt/index.php>`_
+ PyQt is a :program:`sip`\ -wrapped binding to the Qt toolkit. Qt is an
+ extensive C++ GUI application development framework that is
+ available for Unix, Windows and Mac OS X. :program:`sip` is a tool
+ for generating bindings for C++ libraries as Python classes, and
+ is specifically designed for Python. The *PyQt3* bindings have a
+ book, `GUI Programming with Python: QT Edition
+ <http://www.commandprompt.com/community/pyqt/>`_ by Boudewijn
+ Rempt. The *PyQt4* bindings also have a book, `Rapid GUI Programming
+ with Python and Qt <http://www.qtrac.eu/pyqtbook.html>`_, by Mark
+ Summerfield.
+
+ `wxPython <http://www.wxpython.org>`_
+ wxPython is a cross-platform GUI toolkit for Python that is built around
+ the popular `wxWidgets <http://www.wxwidgets.org/>`_ (formerly wxWindows)
+ C++ toolkit.  It provides a native look and feel for applications on
+ Windows, Mac OS X, and Unix systems by using each platform's native
+ widgets where ever possible, (GTK+ on Unix-like systems).  In addition to
+ an extensive set of widgets, wxPython provides classes for online
+ documentation and context sensitive help, printing, HTML viewing,
+ low-level device context drawing, drag and drop, system clipboard access,
+ an XML-based resource format and more, including an ever growing library
+ of user-contributed modules.  wxPython has a book, `wxPython in Action
+ <http://www.amazon.com/exec/obidos/ASIN/1932394621>`_, by Noel Rappin and
+ Robin Dunn.
+
+PyGTK, PyQt, and wxPython, all have a modern look and feel and far more
+widgets and better documentation than Tkinter. In addition,
+there are many other GUI toolkits for Python, both cross-platform, and
+platform-specific. See the `GUI Programming
+<http://wiki.python.org/moin/GuiProgramming>`_ page in the Python Wiki for a
+much more complete list, and also for links to documents where the
+different GUI toolkits are compared.
+
diff --git a/Doc/library/parser.rst b/Doc/library/parser.rst
new file mode 100644
index 0000000000..b7675617fd
--- /dev/null
+++ b/Doc/library/parser.rst
@@ -0,0 +1,683 @@
+
+:mod:`parser` --- Access Python parse trees
+===========================================
+
+.. module:: parser
+ :synopsis: Access parse trees for Python source code.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. % Copyright 1995 Virginia Polytechnic Institute and State University
+.. % and Fred L. Drake, Jr. This copyright notice must be distributed on
+.. % all copies, but this document otherwise may be distributed as part
+.. % of the Python distribution. No fee may be charged for this document
+.. % in any representation, either on paper or electronically. This
+.. % restriction does not affect other elements in a distributed package
+.. % in any way.
+
+.. index:: single: parsing; Python source code
+
+The :mod:`parser` module provides an interface to Python's internal parser and
+byte-code compiler. The primary purpose for this interface is to allow Python
+code to edit the parse tree of a Python expression and create executable code
+from this. This is better than trying to parse and modify an arbitrary Python
+code fragment as a string because parsing is performed in a manner identical to
+the code forming the application. It is also faster.
+
+There are a few things to note about this module which are important to making
+use of the data structures created. This is not a tutorial on editing the parse
+trees for Python code, but some examples of using the :mod:`parser` module are
+presented.
+
+Most importantly, a good understanding of the Python grammar processed by the
+internal parser is required. For full information on the language syntax, refer
+to :ref:`reference-index`. The parser
+itself is created from a grammar specification defined in the file
+:file:`Grammar/Grammar` in the standard Python distribution. The parse trees
+stored in the AST objects created by this module are the actual output from the
+internal parser when created by the :func:`expr` or :func:`suite` functions,
+described below. The AST objects created by :func:`sequence2ast` faithfully
+simulate those structures. Be aware that the values of the sequences which are
+considered "correct" will vary from one version of Python to another as the
+formal grammar for the language is revised. However, transporting code from one
+Python version to another as source text will always allow correct parse trees
+to be created in the target version, with the only restriction being that
+migrating to an older version of the interpreter will not support more recent
+language constructs. The parse trees are not typically compatible from one
+version to another, whereas source code has always been forward-compatible.
+
+Each element of the sequences returned by :func:`ast2list` or :func:`ast2tuple`
+has a simple form. Sequences representing non-terminal elements in the grammar
+always have a length greater than one. The first element is an integer which
+identifies a production in the grammar. These integers are given symbolic names
+in the C header file :file:`Include/graminit.h` and the Python module
+:mod:`symbol`. Each additional element of the sequence represents a component
+of the production as recognized in the input string: these are always sequences
+which have the same form as the parent. An important aspect of this structure
+which should be noted is that keywords used to identify the parent node type,
+such as the keyword :keyword:`if` in an :const:`if_stmt`, are included in the
+node tree without any special treatment. For example, the :keyword:`if` keyword
+is represented by the tuple ``(1, 'if')``, where ``1`` is the numeric value
+associated with all :const:`NAME` tokens, including variable and function names
+defined by the user. In an alternate form returned when line number information
+is requested, the same token might be represented as ``(1, 'if', 12)``, where
+the ``12`` represents the line number at which the terminal symbol was found.
+
+Terminal elements are represented in much the same way, but without any child
+elements and the addition of the source text which was identified. The example
+of the :keyword:`if` keyword above is representative. The various types of
+terminal symbols are defined in the C header file :file:`Include/token.h` and
+the Python module :mod:`token`.
+
+The AST objects are not required to support the functionality of this module,
+but are provided for three purposes: to allow an application to amortize the
+cost of processing complex parse trees, to provide a parse tree representation
+which conserves memory space when compared to the Python list or tuple
+representation, and to ease the creation of additional modules in C which
+manipulate parse trees. A simple "wrapper" class may be created in Python to
+hide the use of AST objects.
+
+The :mod:`parser` module defines functions for a few distinct purposes. The
+most important purposes are to create AST objects and to convert AST objects to
+other representations such as parse trees and compiled code objects, but there
+are also functions which serve to query the type of parse tree represented by an
+AST object.
+
+
+.. seealso::
+
+ Module :mod:`symbol`
+ Useful constants representing internal nodes of the parse tree.
+
+ Module :mod:`token`
+ Useful constants representing leaf nodes of the parse tree and functions for
+ testing node values.
+
+
+.. _creating-asts:
+
+Creating AST Objects
+--------------------
+
+AST objects may be created from source code or from a parse tree. When creating
+an AST object from source, different functions are used to create the ``'eval'``
+and ``'exec'`` forms.
+
+
+.. function:: expr(source)
+
+ The :func:`expr` function parses the parameter *source* as if it were an input
+ to ``compile(source, 'file.py', 'eval')``. If the parse succeeds, an AST object
+ is created to hold the internal parse tree representation, otherwise an
+ appropriate exception is thrown.
+
+
+.. function:: suite(source)
+
+ The :func:`suite` function parses the parameter *source* as if it were an input
+ to ``compile(source, 'file.py', 'exec')``. If the parse succeeds, an AST object
+ is created to hold the internal parse tree representation, otherwise an
+ appropriate exception is thrown.
+
+
+.. function:: sequence2ast(sequence)
+
+ This function accepts a parse tree represented as a sequence and builds an
+ internal representation if possible. If it can validate that the tree conforms
+ to the Python grammar and all nodes are valid node types in the host version of
+ Python, an AST object is created from the internal representation and returned
+ to the called. If there is a problem creating the internal representation, or
+ if the tree cannot be validated, a :exc:`ParserError` exception is thrown. An
+ AST object created this way should not be assumed to compile correctly; normal
+ exceptions thrown by compilation may still be initiated when the AST object is
+ passed to :func:`compileast`. This may indicate problems not related to syntax
+ (such as a :exc:`MemoryError` exception), but may also be due to constructs such
+ as the result of parsing ``del f(0)``, which escapes the Python parser but is
+ checked by the bytecode compiler.
+
+ Sequences representing terminal tokens may be represented as either two-element
+ lists of the form ``(1, 'name')`` or as three-element lists of the form ``(1,
+ 'name', 56)``. If the third element is present, it is assumed to be a valid
+ line number. The line number may be specified for any subset of the terminal
+ symbols in the input tree.
+
+
+.. function:: tuple2ast(sequence)
+
+ This is the same function as :func:`sequence2ast`. This entry point is
+ maintained for backward compatibility.
+
+
+.. _converting-asts:
+
+Converting AST Objects
+----------------------
+
+AST objects, regardless of the input used to create them, may be converted to
+parse trees represented as list- or tuple- trees, or may be compiled into
+executable code objects. Parse trees may be extracted with or without line
+numbering information.
+
+
+.. function:: ast2list(ast[, line_info])
+
+ This function accepts an AST object from the caller in *ast* and returns a
+ Python list representing the equivalent parse tree. The resulting list
+ representation can be used for inspection or the creation of a new parse tree in
+ list form. This function does not fail so long as memory is available to build
+ the list representation. If the parse tree will only be used for inspection,
+ :func:`ast2tuple` should be used instead to reduce memory consumption and
+ fragmentation. When the list representation is required, this function is
+ significantly faster than retrieving a tuple representation and converting that
+ to nested lists.
+
+ If *line_info* is true, line number information will be included for all
+ terminal tokens as a third element of the list representing the token. Note
+ that the line number provided specifies the line on which the token *ends*.
+ This information is omitted if the flag is false or omitted.
+
+
+.. function:: ast2tuple(ast[, line_info])
+
+ This function accepts an AST object from the caller in *ast* and returns a
+ Python tuple representing the equivalent parse tree. Other than returning a
+ tuple instead of a list, this function is identical to :func:`ast2list`.
+
+ If *line_info* is true, line number information will be included for all
+ terminal tokens as a third element of the list representing the token. This
+ information is omitted if the flag is false or omitted.
+
+
+.. function:: compileast(ast[, filename='<ast>'])
+
+ .. index::
+ builtin: exec
+ builtin: eval
+
+ The Python byte compiler can be invoked on an AST object to produce code objects
+ which can be used as part of a call to the built-in :func:`exec` or :func:`eval`
+ functions. This function provides the interface to the compiler, passing the
+ internal parse tree from *ast* to the parser, using the source file name
+ specified by the *filename* parameter. The default value supplied for *filename*
+ indicates that the source was an AST object.
+
+ Compiling an AST object may result in exceptions related to compilation; an
+ example would be a :exc:`SyntaxError` caused by the parse tree for ``del f(0)``:
+ this statement is considered legal within the formal grammar for Python but is
+ not a legal language construct. The :exc:`SyntaxError` raised for this
+ condition is actually generated by the Python byte-compiler normally, which is
+ why it can be raised at this point by the :mod:`parser` module. Most causes of
+ compilation failure can be diagnosed programmatically by inspection of the parse
+ tree.
+
+
+.. _querying-asts:
+
+Queries on AST Objects
+----------------------
+
+Two functions are provided which allow an application to determine if an AST was
+created as an expression or a suite. Neither of these functions can be used to
+determine if an AST was created from source code via :func:`expr` or
+:func:`suite` or from a parse tree via :func:`sequence2ast`.
+
+
+.. function:: isexpr(ast)
+
+ .. index:: builtin: compile
+
+ When *ast* represents an ``'eval'`` form, this function returns true, otherwise
+ it returns false. This is useful, since code objects normally cannot be queried
+ for this information using existing built-in functions. Note that the code
+ objects created by :func:`compileast` cannot be queried like this either, and
+ are identical to those created by the built-in :func:`compile` function.
+
+
+.. function:: issuite(ast)
+
+ This function mirrors :func:`isexpr` in that it reports whether an AST object
+ represents an ``'exec'`` form, commonly known as a "suite." It is not safe to
+ assume that this function is equivalent to ``not isexpr(ast)``, as additional
+ syntactic fragments may be supported in the future.
+
+
+.. _ast-errors:
+
+Exceptions and Error Handling
+-----------------------------
+
+The parser module defines a single exception, but may also pass other built-in
+exceptions from other portions of the Python runtime environment. See each
+function for information about the exceptions it can raise.
+
+
+.. exception:: ParserError
+
+ Exception raised when a failure occurs within the parser module. This is
+ generally produced for validation failures rather than the built in
+ :exc:`SyntaxError` thrown during normal parsing. The exception argument is
+ either a string describing the reason of the failure or a tuple containing a
+ sequence causing the failure from a parse tree passed to :func:`sequence2ast`
+ and an explanatory string. Calls to :func:`sequence2ast` need to be able to
+ handle either type of exception, while calls to other functions in the module
+ will only need to be aware of the simple string values.
+
+Note that the functions :func:`compileast`, :func:`expr`, and :func:`suite` may
+throw exceptions which are normally thrown by the parsing and compilation
+process. These include the built in exceptions :exc:`MemoryError`,
+:exc:`OverflowError`, :exc:`SyntaxError`, and :exc:`SystemError`. In these
+cases, these exceptions carry all the meaning normally associated with them.
+Refer to the descriptions of each function for detailed information.
+
+
+.. _ast-objects:
+
+AST Objects
+-----------
+
+Ordered and equality comparisons are supported between AST objects. Pickling of
+AST objects (using the :mod:`pickle` module) is also supported.
+
+
+.. data:: ASTType
+
+ The type of the objects returned by :func:`expr`, :func:`suite` and
+ :func:`sequence2ast`.
+
+AST objects have the following methods:
+
+
+.. method:: AST.compile([filename])
+
+ Same as ``compileast(ast, filename)``.
+
+
+.. method:: AST.isexpr()
+
+ Same as ``isexpr(ast)``.
+
+
+.. method:: AST.issuite()
+
+ Same as ``issuite(ast)``.
+
+
+.. method:: AST.tolist([line_info])
+
+ Same as ``ast2list(ast, line_info)``.
+
+
+.. method:: AST.totuple([line_info])
+
+ Same as ``ast2tuple(ast, line_info)``.
+
+
+.. _ast-examples:
+
+Examples
+--------
+
+.. index:: builtin: compile
+
+The parser modules allows operations to be performed on the parse tree of Python
+source code before the bytecode is generated, and provides for inspection of the
+parse tree for information gathering purposes. Two examples are presented. The
+simple example demonstrates emulation of the :func:`compile` built-in function
+and the complex example shows the use of a parse tree for information discovery.
+
+
+Emulation of :func:`compile`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+While many useful operations may take place between parsing and bytecode
+generation, the simplest operation is to do nothing. For this purpose, using
+the :mod:`parser` module to produce an intermediate data structure is equivalent
+to the code ::
+
+ >>> code = compile('a + 5', 'file.py', 'eval')
+ >>> a = 5
+ >>> eval(code)
+ 10
+
+The equivalent operation using the :mod:`parser` module is somewhat longer, and
+allows the intermediate internal parse tree to be retained as an AST object::
+
+ >>> import parser
+ >>> ast = parser.expr('a + 5')
+ >>> code = ast.compile('file.py')
+ >>> a = 5
+ >>> eval(code)
+ 10
+
+An application which needs both AST and code objects can package this code into
+readily available functions::
+
+ import parser
+
+ def load_suite(source_string):
+ ast = parser.suite(source_string)
+ return ast, ast.compile()
+
+ def load_expression(source_string):
+ ast = parser.expr(source_string)
+ return ast, ast.compile()
+
+
+Information Discovery
+^^^^^^^^^^^^^^^^^^^^^
+
+.. index::
+ single: string; documentation
+ single: docstrings
+
+Some applications benefit from direct access to the parse tree. The remainder
+of this section demonstrates how the parse tree provides access to module
+documentation defined in docstrings without requiring that the code being
+examined be loaded into a running interpreter via :keyword:`import`. This can
+be very useful for performing analyses of untrusted code.
+
+Generally, the example will demonstrate how the parse tree may be traversed to
+distill interesting information. Two functions and a set of classes are
+developed which provide programmatic access to high level function and class
+definitions provided by a module. The classes extract information from the
+parse tree and provide access to the information at a useful semantic level, one
+function provides a simple low-level pattern matching capability, and the other
+function defines a high-level interface to the classes by handling file
+operations on behalf of the caller. All source files mentioned here which are
+not part of the Python installation are located in the :file:`Demo/parser/`
+directory of the distribution.
+
+The dynamic nature of Python allows the programmer a great deal of flexibility,
+but most modules need only a limited measure of this when defining classes,
+functions, and methods. In this example, the only definitions that will be
+considered are those which are defined in the top level of their context, e.g.,
+a function defined by a :keyword:`def` statement at column zero of a module, but
+not a function defined within a branch of an :keyword:`if` ... :keyword:`else`
+construct, though there are some good reasons for doing so in some situations.
+Nesting of definitions will be handled by the code developed in the example.
+
+To construct the upper-level extraction methods, we need to know what the parse
+tree structure looks like and how much of it we actually need to be concerned
+about. Python uses a moderately deep parse tree so there are a large number of
+intermediate nodes. It is important to read and understand the formal grammar
+used by Python. This is specified in the file :file:`Grammar/Grammar` in the
+distribution. Consider the simplest case of interest when searching for
+docstrings: a module consisting of a docstring and nothing else. (See file
+:file:`docstring.py`.) ::
+
+ """Some documentation.
+ """
+
+Using the interpreter to take a look at the parse tree, we find a bewildering
+mass of numbers and parentheses, with the documentation buried deep in nested
+tuples. ::
+
+ >>> import parser
+ >>> import pprint
+ >>> ast = parser.suite(open('docstring.py').read())
+ >>> tup = ast.totuple()
+ >>> pprint.pprint(tup)
+ (257,
+ (264,
+ (265,
+ (266,
+ (267,
+ (307,
+ (287,
+ (288,
+ (289,
+ (290,
+ (292,
+ (293,
+ (294,
+ (295,
+ (296,
+ (297,
+ (298,
+ (299,
+ (300, (3, '"""Some documentation.\n"""'))))))))))))))))),
+ (4, ''))),
+ (4, ''),
+ (0, ''))
+
+The numbers at the first element of each node in the tree are the node types;
+they map directly to terminal and non-terminal symbols in the grammar.
+Unfortunately, they are represented as integers in the internal representation,
+and the Python structures generated do not change that. However, the
+:mod:`symbol` and :mod:`token` modules provide symbolic names for the node types
+and dictionaries which map from the integers to the symbolic names for the node
+types.
+
+In the output presented above, the outermost tuple contains four elements: the
+integer ``257`` and three additional tuples. Node type ``257`` has the symbolic
+name :const:`file_input`. Each of these inner tuples contains an integer as the
+first element; these integers, ``264``, ``4``, and ``0``, represent the node
+types :const:`stmt`, :const:`NEWLINE`, and :const:`ENDMARKER`, respectively.
+Note that these values may change depending on the version of Python you are
+using; consult :file:`symbol.py` and :file:`token.py` for details of the
+mapping. It should be fairly clear that the outermost node is related primarily
+to the input source rather than the contents of the file, and may be disregarded
+for the moment. The :const:`stmt` node is much more interesting. In
+particular, all docstrings are found in subtrees which are formed exactly as
+this node is formed, with the only difference being the string itself. The
+association between the docstring in a similar tree and the defined entity
+(class, function, or module) which it describes is given by the position of the
+docstring subtree within the tree defining the described structure.
+
+By replacing the actual docstring with something to signify a variable component
+of the tree, we allow a simple pattern matching approach to check any given
+subtree for equivalence to the general pattern for docstrings. Since the
+example demonstrates information extraction, we can safely require that the tree
+be in tuple form rather than list form, allowing a simple variable
+representation to be ``['variable_name']``. A simple recursive function can
+implement the pattern matching, returning a Boolean and a dictionary of variable
+name to value mappings. (See file :file:`example.py`.) ::
+
+ from types import ListType, TupleType
+
+ def match(pattern, data, vars=None):
+ if vars is None:
+ vars = {}
+ if type(pattern) is ListType:
+ vars[pattern[0]] = data
+ return 1, vars
+ if type(pattern) is not TupleType:
+ return (pattern == data), vars
+ if len(data) != len(pattern):
+ return 0, vars
+ for pattern, data in map(None, pattern, data):
+ same, vars = match(pattern, data, vars)
+ if not same:
+ break
+ return same, vars
+
+Using this simple representation for syntactic variables and the symbolic node
+types, the pattern for the candidate docstring subtrees becomes fairly readable.
+(See file :file:`example.py`.) ::
+
+ import symbol
+ import token
+
+ DOCSTRING_STMT_PATTERN = (
+ symbol.stmt,
+ (symbol.simple_stmt,
+ (symbol.small_stmt,
+ (symbol.expr_stmt,
+ (symbol.testlist,
+ (symbol.test,
+ (symbol.and_test,
+ (symbol.not_test,
+ (symbol.comparison,
+ (symbol.expr,
+ (symbol.xor_expr,
+ (symbol.and_expr,
+ (symbol.shift_expr,
+ (symbol.arith_expr,
+ (symbol.term,
+ (symbol.factor,
+ (symbol.power,
+ (symbol.atom,
+ (token.STRING, ['docstring'])
+ )))))))))))))))),
+ (token.NEWLINE, '')
+ ))
+
+Using the :func:`match` function with this pattern, extracting the module
+docstring from the parse tree created previously is easy::
+
+ >>> found, vars = match(DOCSTRING_STMT_PATTERN, tup[1])
+ >>> found
+ 1
+ >>> vars
+ {'docstring': '"""Some documentation.\n"""'}
+
+Once specific data can be extracted from a location where it is expected, the
+question of where information can be expected needs to be answered. When
+dealing with docstrings, the answer is fairly simple: the docstring is the first
+:const:`stmt` node in a code block (:const:`file_input` or :const:`suite` node
+types). A module consists of a single :const:`file_input` node, and class and
+function definitions each contain exactly one :const:`suite` node. Classes and
+functions are readily identified as subtrees of code block nodes which start
+with ``(stmt, (compound_stmt, (classdef, ...`` or ``(stmt, (compound_stmt,
+(funcdef, ...``. Note that these subtrees cannot be matched by :func:`match`
+since it does not support multiple sibling nodes to match without regard to
+number. A more elaborate matching function could be used to overcome this
+limitation, but this is sufficient for the example.
+
+Given the ability to determine whether a statement might be a docstring and
+extract the actual string from the statement, some work needs to be performed to
+walk the parse tree for an entire module and extract information about the names
+defined in each context of the module and associate any docstrings with the
+names. The code to perform this work is not complicated, but bears some
+explanation.
+
+The public interface to the classes is straightforward and should probably be
+somewhat more flexible. Each "major" block of the module is described by an
+object providing several methods for inquiry and a constructor which accepts at
+least the subtree of the complete parse tree which it represents. The
+:class:`ModuleInfo` constructor accepts an optional *name* parameter since it
+cannot otherwise determine the name of the module.
+
+The public classes include :class:`ClassInfo`, :class:`FunctionInfo`, and
+:class:`ModuleInfo`. All objects provide the methods :meth:`get_name`,
+:meth:`get_docstring`, :meth:`get_class_names`, and :meth:`get_class_info`. The
+:class:`ClassInfo` objects support :meth:`get_method_names` and
+:meth:`get_method_info` while the other classes provide
+:meth:`get_function_names` and :meth:`get_function_info`.
+
+Within each of the forms of code block that the public classes represent, most
+of the required information is in the same form and is accessed in the same way,
+with classes having the distinction that functions defined at the top level are
+referred to as "methods." Since the difference in nomenclature reflects a real
+semantic distinction from functions defined outside of a class, the
+implementation needs to maintain the distinction. Hence, most of the
+functionality of the public classes can be implemented in a common base class,
+:class:`SuiteInfoBase`, with the accessors for function and method information
+provided elsewhere. Note that there is only one class which represents function
+and method information; this parallels the use of the :keyword:`def` statement
+to define both types of elements.
+
+Most of the accessor functions are declared in :class:`SuiteInfoBase` and do not
+need to be overridden by subclasses. More importantly, the extraction of most
+information from a parse tree is handled through a method called by the
+:class:`SuiteInfoBase` constructor. The example code for most of the classes is
+clear when read alongside the formal grammar, but the method which recursively
+creates new information objects requires further examination. Here is the
+relevant part of the :class:`SuiteInfoBase` definition from :file:`example.py`::
+
+ class SuiteInfoBase:
+ _docstring = ''
+ _name = ''
+
+ def __init__(self, tree = None):
+ self._class_info = {}
+ self._function_info = {}
+ if tree:
+ self._extract_info(tree)
+
+ def _extract_info(self, tree):
+ # extract docstring
+ if len(tree) == 2:
+ found, vars = match(DOCSTRING_STMT_PATTERN[1], tree[1])
+ else:
+ found, vars = match(DOCSTRING_STMT_PATTERN, tree[3])
+ if found:
+ self._docstring = eval(vars['docstring'])
+ # discover inner definitions
+ for node in tree[1:]:
+ found, vars = match(COMPOUND_STMT_PATTERN, node)
+ if found:
+ cstmt = vars['compound']
+ if cstmt[0] == symbol.funcdef:
+ name = cstmt[2][1]
+ self._function_info[name] = FunctionInfo(cstmt)
+ elif cstmt[0] == symbol.classdef:
+ name = cstmt[2][1]
+ self._class_info[name] = ClassInfo(cstmt)
+
+After initializing some internal state, the constructor calls the
+:meth:`_extract_info` method. This method performs the bulk of the information
+extraction which takes place in the entire example. The extraction has two
+distinct phases: the location of the docstring for the parse tree passed in, and
+the discovery of additional definitions within the code block represented by the
+parse tree.
+
+The initial :keyword:`if` test determines whether the nested suite is of the
+"short form" or the "long form." The short form is used when the code block is
+on the same line as the definition of the code block, as in ::
+
+ def square(x): "Square an argument."; return x ** 2
+
+while the long form uses an indented block and allows nested definitions::
+
+ def make_power(exp):
+ "Make a function that raises an argument to the exponent `exp'."
+ def raiser(x, y=exp):
+ return x ** y
+ return raiser
+
+When the short form is used, the code block may contain a docstring as the
+first, and possibly only, :const:`small_stmt` element. The extraction of such a
+docstring is slightly different and requires only a portion of the complete
+pattern used in the more common case. As implemented, the docstring will only
+be found if there is only one :const:`small_stmt` node in the
+:const:`simple_stmt` node. Since most functions and methods which use the short
+form do not provide a docstring, this may be considered sufficient. The
+extraction of the docstring proceeds using the :func:`match` function as
+described above, and the value of the docstring is stored as an attribute of the
+:class:`SuiteInfoBase` object.
+
+After docstring extraction, a simple definition discovery algorithm operates on
+the :const:`stmt` nodes of the :const:`suite` node. The special case of the
+short form is not tested; since there are no :const:`stmt` nodes in the short
+form, the algorithm will silently skip the single :const:`simple_stmt` node and
+correctly not discover any nested definitions.
+
+Each statement in the code block is categorized as a class definition, function
+or method definition, or something else. For the definition statements, the
+name of the element defined is extracted and a representation object appropriate
+to the definition is created with the defining subtree passed as an argument to
+the constructor. The representation objects are stored in instance variables
+and may be retrieved by name using the appropriate accessor methods.
+
+The public classes provide any accessors required which are more specific than
+those provided by the :class:`SuiteInfoBase` class, but the real extraction
+algorithm remains common to all forms of code blocks. A high-level function can
+be used to extract the complete set of information from a source file. (See
+file :file:`example.py`.) ::
+
+ def get_docs(fileName):
+ import os
+ import parser
+
+ source = open(fileName).read()
+ basename = os.path.basename(os.path.splitext(fileName)[0])
+ ast = parser.suite(source)
+ return ModuleInfo(ast.totuple(), basename)
+
+This provides an easy-to-use interface to the documentation of a module. If
+information is required which is not extracted by the code of this example, the
+code may be extended at clearly defined points to provide additional
+capabilities.
+
diff --git a/Doc/library/pdb.rst b/Doc/library/pdb.rst
new file mode 100644
index 0000000000..804dd237ac
--- /dev/null
+++ b/Doc/library/pdb.rst
@@ -0,0 +1,409 @@
+
+.. _debugger:
+
+*******************
+The Python Debugger
+*******************
+
+.. module:: pdb
+ :synopsis: The Python debugger for interactive interpreters.
+
+
+.. index:: single: debugging
+
+The module :mod:`pdb` defines an interactive source code debugger for Python
+programs. It supports setting (conditional) breakpoints and single stepping at
+the source line level, inspection of stack frames, source code listing, and
+evaluation of arbitrary Python code in the context of any stack frame. It also
+supports post-mortem debugging and can be called under program control.
+
+.. index::
+ single: Pdb (class in pdb)
+ module: bdb
+ module: cmd
+
+The debugger is extensible --- it is actually defined as the class :class:`Pdb`.
+This is currently undocumented but easily understood by reading the source. The
+extension interface uses the modules :mod:`bdb` (undocumented) and :mod:`cmd`.
+
+The debugger's prompt is ``(Pdb)``. Typical usage to run a program under control
+of the debugger is::
+
+ >>> import pdb
+ >>> import mymodule
+ >>> pdb.run('mymodule.test()')
+ > <string>(0)?()
+ (Pdb) continue
+ > <string>(1)?()
+ (Pdb) continue
+ NameError: 'spam'
+ > <string>(1)?()
+ (Pdb)
+
+:file:`pdb.py` can also be invoked as a script to debug other scripts. For
+example::
+
+ python -m pdb myscript.py
+
+When invoked as a script, pdb will automatically enter post-mortem debugging if
+the program being debugged exits abnormally. After post-mortem debugging (or
+after normal exit of the program), pdb will restart the program. Automatic
+restarting preserves pdb's state (such as breakpoints) and in most cases is more
+useful than quitting the debugger upon program's exit.
+
+.. versionadded:: 2.4
+ Restarting post-mortem behavior added.
+
+Typical usage to inspect a crashed program is::
+
+ >>> import pdb
+ >>> import mymodule
+ >>> mymodule.test()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "./mymodule.py", line 4, in test
+ test2()
+ File "./mymodule.py", line 3, in test2
+ print spam
+ NameError: spam
+ >>> pdb.pm()
+ > ./mymodule.py(3)test2()
+ -> print spam
+ (Pdb)
+
+The module defines the following functions; each enters the debugger in a
+slightly different way:
+
+
+.. function:: run(statement[, globals[, locals]])
+
+ Execute the *statement* (given as a string) under debugger control. The
+ debugger prompt appears before any code is executed; you can set breakpoints and
+ type ``continue``, or you can step through the statement using ``step`` or
+ ``next`` (all these commands are explained below). The optional *globals* and
+ *locals* arguments specify the environment in which the code is executed; by
+ default the dictionary of the module :mod:`__main__` is used. (See the
+ explanation of the built-in :func:`exec` or :func:`eval` functions.)
+
+
+.. function:: runeval(expression[, globals[, locals]])
+
+ Evaluate the *expression* (given as a string) under debugger control. When
+ :func:`runeval` returns, it returns the value of the expression. Otherwise this
+ function is similar to :func:`run`.
+
+
+.. function:: runcall(function[, argument, ...])
+
+ Call the *function* (a function or method object, not a string) with the given
+ arguments. When :func:`runcall` returns, it returns whatever the function call
+ returned. The debugger prompt appears as soon as the function is entered.
+
+
+.. function:: set_trace()
+
+ Enter the debugger at the calling stack frame. This is useful to hard-code a
+ breakpoint at a given point in a program, even if the code is not otherwise
+ being debugged (e.g. when an assertion fails).
+
+
+.. function:: post_mortem(traceback)
+
+ Enter post-mortem debugging of the given *traceback* object.
+
+
+.. function:: pm()
+
+ Enter post-mortem debugging of the traceback found in ``sys.last_traceback``.
+
+
+.. _debugger-commands:
+
+Debugger Commands
+=================
+
+The debugger recognizes the following commands. Most commands can be
+abbreviated to one or two letters; e.g. ``h(elp)`` means that either ``h`` or
+``help`` can be used to enter the help command (but not ``he`` or ``hel``, nor
+``H`` or ``Help`` or ``HELP``). Arguments to commands must be separated by
+whitespace (spaces or tabs). Optional arguments are enclosed in square brackets
+(``[]``) in the command syntax; the square brackets must not be typed.
+Alternatives in the command syntax are separated by a vertical bar (``|``).
+
+Entering a blank line repeats the last command entered. Exception: if the last
+command was a ``list`` command, the next 11 lines are listed.
+
+Commands that the debugger doesn't recognize are assumed to be Python statements
+and are executed in the context of the program being debugged. Python
+statements can also be prefixed with an exclamation point (``!``). This is a
+powerful way to inspect the program being debugged; it is even possible to
+change a variable or call a function. When an exception occurs in such a
+statement, the exception name is printed but the debugger's state is not
+changed.
+
+Multiple commands may be entered on a single line, separated by ``;;``. (A
+single ``;`` is not used as it is the separator for multiple commands in a line
+that is passed to the Python parser.) No intelligence is applied to separating
+the commands; the input is split at the first ``;;`` pair, even if it is in the
+middle of a quoted string.
+
+The debugger supports aliases. Aliases can have parameters which allows one a
+certain level of adaptability to the context under examination.
+
+.. index::
+ pair: .pdbrc; file
+ triple: debugger; configuration; file
+
+If a file :file:`.pdbrc` exists in the user's home directory or in the current
+directory, it is read in and executed as if it had been typed at the debugger
+prompt. This is particularly useful for aliases. If both files exist, the one
+in the home directory is read first and aliases defined there can be overridden
+by the local file.
+
+h(elp) [*command*]
+ Without argument, print the list of available commands. With a *command* as
+ argument, print help about that command. ``help pdb`` displays the full
+ documentation file; if the environment variable :envvar:`PAGER` is defined, the
+ file is piped through that command instead. Since the *command* argument must
+ be an identifier, ``help exec`` must be entered to get help on the ``!``
+ command.
+
+w(here)
+ Print a stack trace, with the most recent frame at the bottom. An arrow
+ indicates the current frame, which determines the context of most commands.
+
+d(own)
+ Move the current frame one level down in the stack trace (to a newer frame).
+
+u(p)
+ Move the current frame one level up in the stack trace (to an older frame).
+
+b(reak) [[*filename*:]*lineno*``|``*function*[, *condition*]]
+ With a *lineno* argument, set a break there in the current file. With a
+ *function* argument, set a break at the first executable statement within that
+ function. The line number may be prefixed with a filename and a colon, to
+ specify a breakpoint in another file (probably one that hasn't been loaded yet).
+ The file is searched on ``sys.path``. Note that each breakpoint is assigned a
+ number to which all the other breakpoint commands refer.
+
+ If a second argument is present, it is an expression which must evaluate to true
+ before the breakpoint is honored.
+
+ Without argument, list all breaks, including for each breakpoint, the number of
+ times that breakpoint has been hit, the current ignore count, and the associated
+ condition if any.
+
+tbreak [[*filename*:]*lineno*``|``*function*[, *condition*]]
+ Temporary breakpoint, which is removed automatically when it is first hit. The
+ arguments are the same as break.
+
+cl(ear) [*bpnumber* [*bpnumber ...*]]
+ With a space separated list of breakpoint numbers, clear those breakpoints.
+ Without argument, clear all breaks (but first ask confirmation).
+
+disable [*bpnumber* [*bpnumber ...*]]
+ Disables the breakpoints given as a space separated list of breakpoint numbers.
+ Disabling a breakpoint means it cannot cause the program to stop execution, but
+ unlike clearing a breakpoint, it remains in the list of breakpoints and can be
+ (re-)enabled.
+
+enable [*bpnumber* [*bpnumber ...*]]
+ Enables the breakpoints specified.
+
+ignore *bpnumber* [*count*]
+ Sets the ignore count for the given breakpoint number. If count is omitted, the
+ ignore count is set to 0. A breakpoint becomes active when the ignore count is
+ zero. When non-zero, the count is decremented each time the breakpoint is
+ reached and the breakpoint is not disabled and any associated condition
+ evaluates to true.
+
+condition *bpnumber* [*condition*]
+ Condition is an expression which must evaluate to true before the breakpoint is
+ honored. If condition is absent, any existing condition is removed; i.e., the
+ breakpoint is made unconditional.
+
+commands [*bpnumber*]
+ Specify a list of commands for breakpoint number *bpnumber*. The commands
+ themselves appear on the following lines. Type a line containing just 'end' to
+ terminate the commands. An example::
+
+ (Pdb) commands 1
+ (com) print some_variable
+ (com) end
+ (Pdb)
+
+ To remove all commands from a breakpoint, type commands and follow it
+ immediately with end; that is, give no commands.
+
+ With no *bpnumber* argument, commands refers to the last breakpoint set.
+
+ You can use breakpoint commands to start your program up again. Simply use the
+ continue command, or step, or any other command that resumes execution.
+
+ Specifying any command resuming execution (currently continue, step, next,
+ return, jump, quit and their abbreviations) terminates the command list (as if
+ that command was immediately followed by end). This is because any time you
+ resume execution (even with a simple next or step), you may encounter· another
+ breakpoint--which could have its own command list, leading to ambiguities about
+ which list to execute.
+
+ If you use the 'silent' command in the command list, the usual message about
+ stopping at a breakpoint is not printed. This may be desirable for breakpoints
+ that are to print a specific message and then continue. If none of the other
+ commands print anything, you see no sign that the breakpoint was reached.
+
+ .. versionadded:: 2.5
+
+s(tep)
+ Execute the current line, stop at the first possible occasion (either in a
+ function that is called or on the next line in the current function).
+
+n(ext)
+ Continue execution until the next line in the current function is reached or it
+ returns. (The difference between ``next`` and ``step`` is that ``step`` stops
+ inside a called function, while ``next`` executes called functions at (nearly)
+ full speed, only stopping at the next line in the current function.)
+
+r(eturn)
+ Continue execution until the current function returns.
+
+c(ont(inue))
+ Continue execution, only stop when a breakpoint is encountered.
+
+j(ump) *lineno*
+ Set the next line that will be executed. Only available in the bottom-most
+ frame. This lets you jump back and execute code again, or jump forward to skip
+ code that you don't want to run.
+
+ It should be noted that not all jumps are allowed --- for instance it is not
+ possible to jump into the middle of a :keyword:`for` loop or out of a
+ :keyword:`finally` clause.
+
+l(ist) [*first*[, *last*]]
+ List source code for the current file. Without arguments, list 11 lines around
+ the current line or continue the previous listing. With one argument, list 11
+ lines around at that line. With two arguments, list the given range; if the
+ second argument is less than the first, it is interpreted as a count.
+
+a(rgs)
+ Print the argument list of the current function.
+
+p *expression*
+ Evaluate the *expression* in the current context and print its value.
+
+ .. note::
+
+ ``print`` can also be used, but is not a debugger command --- this executes the
+ Python :keyword:`print` statement.
+
+pp *expression*
+ Like the ``p`` command, except the value of the expression is pretty-printed
+ using the :mod:`pprint` module.
+
+alias [*name* [command]]
+ Creates an alias called *name* that executes *command*. The command must *not*
+ be enclosed in quotes. Replaceable parameters can be indicated by ``%1``,
+ ``%2``, and so on, while ``%*`` is replaced by all the parameters. If no
+ command is given, the current alias for *name* is shown. If no arguments are
+ given, all aliases are listed.
+
+ Aliases may be nested and can contain anything that can be legally typed at the
+ pdb prompt. Note that internal pdb commands *can* be overridden by aliases.
+ Such a command is then hidden until the alias is removed. Aliasing is
+ recursively applied to the first word of the command line; all other words in
+ the line are left alone.
+
+ As an example, here are two useful aliases (especially when placed in the
+ :file:`.pdbrc` file)::
+
+ #Print instance variables (usage "pi classInst")
+ alias pi for k in %1.__dict__.keys(): print "%1.",k,"=",%1.__dict__[k]
+ #Print instance variables in self
+ alias ps pi self
+
+unalias *name*
+ Deletes the specified alias.
+
+[!]*statement*
+ Execute the (one-line) *statement* in the context of the current stack frame.
+ The exclamation point can be omitted unless the first word of the statement
+ resembles a debugger command. To set a global variable, you can prefix the
+ assignment command with a ``global`` command on the same line, e.g.::
+
+ (Pdb) global list_options; list_options = ['-l']
+ (Pdb)
+
+run [*args* ...]
+ Restart the debugged python program. If an argument is supplied, it is splitted
+ with "shlex" and the result is used as the new sys.argv. History, breakpoints,
+ actions and debugger options are preserved. "restart" is an alias for "run".
+
+ .. versionadded:: 2.6
+
+q(uit)
+ Quit from the debugger. The program being executed is aborted.
+
+
+.. _debugger-hooks:
+
+How It Works
+============
+
+Some changes were made to the interpreter:
+
+* ``sys.settrace(func)`` sets the global trace function
+
+* there can also a local trace function (see later)
+
+Trace functions have three arguments: *frame*, *event*, and *arg*. *frame* is
+the current stack frame. *event* is a string: ``'call'``, ``'line'``,
+``'return'``, ``'exception'``, ``'c_call'``, ``'c_return'``, or
+``'c_exception'``. *arg* depends on the event type.
+
+The global trace function is invoked (with *event* set to ``'call'``) whenever a
+new local scope is entered; it should return a reference to the local trace
+function to be used that scope, or ``None`` if the scope shouldn't be traced.
+
+The local trace function should return a reference to itself (or to another
+function for further tracing in that scope), or ``None`` to turn off tracing in
+that scope.
+
+Instance methods are accepted (and very useful!) as trace functions.
+
+The events have the following meaning:
+
+``'call'``
+ A function is called (or some other code block entered). The global trace
+ function is called; *arg* is ``None``; the return value specifies the local
+ trace function.
+
+``'line'``
+ The interpreter is about to execute a new line of code (sometimes multiple line
+ events on one line exist). The local trace function is called; *arg* is
+ ``None``; the return value specifies the new local trace function.
+
+``'return'``
+ A function (or other code block) is about to return. The local trace function
+ is called; *arg* is the value that will be returned. The trace function's
+ return value is ignored.
+
+``'exception'``
+ An exception has occurred. The local trace function is called; *arg* is a
+ triple ``(exception, value, traceback)``; the return value specifies the new
+ local trace function.
+
+``'c_call'``
+ A C function is about to be called. This may be an extension function or a
+ builtin. *arg* is the C function object.
+
+``'c_return'``
+ A C function has returned. *arg* is ``None``.
+
+``'c_exception'``
+ A C function has thrown an exception. *arg* is ``None``.
+
+Note that as an exception is propagated down the chain of callers, an
+``'exception'`` event is generated at each level.
+
+For more information on code and frame objects, refer to :ref:`types`.
+
diff --git a/Doc/library/persistence.rst b/Doc/library/persistence.rst
new file mode 100644
index 0000000000..78e40f6446
--- /dev/null
+++ b/Doc/library/persistence.rst
@@ -0,0 +1,32 @@
+
+.. _persistence:
+
+****************
+Data Persistence
+****************
+
+The modules described in this chapter support storing Python data in a
+persistent form on disk. The :mod:`pickle` and :mod:`marshal` modules can turn
+many Python data types into a stream of bytes and then recreate the objects from
+the bytes. The various DBM-related modules support a family of hash-based file
+formats that store a mapping of strings to other strings. The :mod:`bsddb`
+module also provides such disk-based string-to-string mappings based on hashing,
+and also supports B-Tree and record-based formats.
+
+The list of modules described in this chapter is:
+
+
+.. toctree::
+
+ pickle.rst
+ copy_reg.rst
+ shelve.rst
+ marshal.rst
+ anydbm.rst
+ whichdb.rst
+ dbm.rst
+ gdbm.rst
+ dbhash.rst
+ bsddb.rst
+ dumbdbm.rst
+ sqlite3.rst
diff --git a/Doc/library/pickle.rst b/Doc/library/pickle.rst
new file mode 100644
index 0000000000..ab19ff89e9
--- /dev/null
+++ b/Doc/library/pickle.rst
@@ -0,0 +1,868 @@
+
+:mod:`pickle` --- Python object serialization
+=============================================
+
+.. index::
+ single: persistence
+ pair: persistent; objects
+ pair: serializing; objects
+ pair: marshalling; objects
+ pair: flattening; objects
+ pair: pickling; objects
+
+.. module:: pickle
+ :synopsis: Convert Python objects to streams of bytes and back.
+
+
+.. % Substantial improvements by Jim Kerr <jbkerr@sr.hp.com>.
+.. % Rewritten by Barry Warsaw <barry@zope.com>
+
+The :mod:`pickle` module implements a fundamental, but powerful algorithm for
+serializing and de-serializing a Python object structure. "Pickling" is the
+process whereby a Python object hierarchy is converted into a byte stream, and
+"unpickling" is the inverse operation, whereby a byte stream is converted back
+into an object hierarchy. Pickling (and unpickling) is alternatively known as
+"serialization", "marshalling," [#]_ or "flattening", however, to avoid
+confusion, the terms used here are "pickling" and "unpickling".
+
+This documentation describes both the :mod:`pickle` module and the
+:mod:`cPickle` module.
+
+
+Relationship to other Python modules
+------------------------------------
+
+The :mod:`pickle` module has an optimized cousin called the :mod:`cPickle`
+module. As its name implies, :mod:`cPickle` is written in C, so it can be up to
+1000 times faster than :mod:`pickle`. However it does not support subclassing
+of the :func:`Pickler` and :func:`Unpickler` classes, because in :mod:`cPickle`
+these are functions, not classes. Most applications have no need for this
+functionality, and can benefit from the improved performance of :mod:`cPickle`.
+Other than that, the interfaces of the two modules are nearly identical; the
+common interface is described in this manual and differences are pointed out
+where necessary. In the following discussions, we use the term "pickle" to
+collectively describe the :mod:`pickle` and :mod:`cPickle` modules.
+
+The data streams the two modules produce are guaranteed to be interchangeable.
+
+Python has a more primitive serialization module called :mod:`marshal`, but in
+general :mod:`pickle` should always be the preferred way to serialize Python
+objects. :mod:`marshal` exists primarily to support Python's :file:`.pyc`
+files.
+
+The :mod:`pickle` module differs from :mod:`marshal` several significant ways:
+
+* The :mod:`pickle` module keeps track of the objects it has already serialized,
+ so that later references to the same object won't be serialized again.
+ :mod:`marshal` doesn't do this.
+
+ This has implications both for recursive objects and object sharing. Recursive
+ objects are objects that contain references to themselves. These are not
+ handled by marshal, and in fact, attempting to marshal recursive objects will
+ crash your Python interpreter. Object sharing happens when there are multiple
+ references to the same object in different places in the object hierarchy being
+ serialized. :mod:`pickle` stores such objects only once, and ensures that all
+ other references point to the master copy. Shared objects remain shared, which
+ can be very important for mutable objects.
+
+* :mod:`marshal` cannot be used to serialize user-defined classes and their
+ instances. :mod:`pickle` can save and restore class instances transparently,
+ however the class definition must be importable and live in the same module as
+ when the object was stored.
+
+* The :mod:`marshal` serialization format is not guaranteed to be portable
+ across Python versions. Because its primary job in life is to support
+ :file:`.pyc` files, the Python implementers reserve the right to change the
+ serialization format in non-backwards compatible ways should the need arise.
+ The :mod:`pickle` serialization format is guaranteed to be backwards compatible
+ across Python releases.
+
+.. warning::
+
+ The :mod:`pickle` module is not intended to be secure against erroneous or
+ maliciously constructed data. Never unpickle data received from an untrusted or
+ unauthenticated source.
+
+Note that serialization is a more primitive notion than persistence; although
+:mod:`pickle` reads and writes file objects, it does not handle the issue of
+naming persistent objects, nor the (even more complicated) issue of concurrent
+access to persistent objects. The :mod:`pickle` module can transform a complex
+object into a byte stream and it can transform the byte stream into an object
+with the same internal structure. Perhaps the most obvious thing to do with
+these byte streams is to write them onto a file, but it is also conceivable to
+send them across a network or store them in a database. The module
+:mod:`shelve` provides a simple interface to pickle and unpickle objects on
+DBM-style database files.
+
+
+Data stream format
+------------------
+
+.. index::
+ single: XDR
+ single: External Data Representation
+
+The data format used by :mod:`pickle` is Python-specific. This has the
+advantage that there are no restrictions imposed by external standards such as
+XDR (which can't represent pointer sharing); however it means that non-Python
+programs may not be able to reconstruct pickled Python objects.
+
+By default, the :mod:`pickle` data format uses a printable ASCII representation.
+This is slightly more voluminous than a binary representation. The big
+advantage of using printable ASCII (and of some other characteristics of
+:mod:`pickle`'s representation) is that for debugging or recovery purposes it is
+possible for a human to read the pickled file with a standard text editor.
+
+There are currently 3 different protocols which can be used for pickling.
+
+* Protocol version 0 is the original ASCII protocol and is backwards compatible
+ with earlier versions of Python.
+
+* Protocol version 1 is the old binary format which is also compatible with
+ earlier versions of Python.
+
+* Protocol version 2 was introduced in Python 2.3. It provides much more
+ efficient pickling of new-style classes.
+
+Refer to :pep:`307` for more information.
+
+If a *protocol* is not specified, protocol 0 is used. If *protocol* is specified
+as a negative value or :const:`HIGHEST_PROTOCOL`, the highest protocol version
+available will be used.
+
+.. versionchanged:: 2.3
+ Introduced the *protocol* parameter.
+
+A binary format, which is slightly more efficient, can be chosen by specifying a
+*protocol* version >= 1.
+
+
+Usage
+-----
+
+To serialize an object hierarchy, you first create a pickler, then you call the
+pickler's :meth:`dump` method. To de-serialize a data stream, you first create
+an unpickler, then you call the unpickler's :meth:`load` method. The
+:mod:`pickle` module provides the following constant:
+
+
+.. data:: HIGHEST_PROTOCOL
+
+ The highest protocol version available. This value can be passed as a
+ *protocol* value.
+
+ .. versionadded:: 2.3
+
+.. note::
+
+ Be sure to always open pickle files created with protocols >= 1 in binary mode.
+ For the old ASCII-based pickle protocol 0 you can use either text mode or binary
+ mode as long as you stay consistent.
+
+ A pickle file written with protocol 0 in binary mode will contain lone linefeeds
+ as line terminators and therefore will look "funny" when viewed in Notepad or
+ other editors which do not support this format.
+
+The :mod:`pickle` module provides the following functions to make the pickling
+process more convenient:
+
+
+.. function:: dump(obj, file[, protocol])
+
+ Write a pickled representation of *obj* to the open file object *file*. This is
+ equivalent to ``Pickler(file, protocol).dump(obj)``.
+
+ If the *protocol* parameter is omitted, protocol 0 is used. If *protocol* is
+ specified as a negative value or :const:`HIGHEST_PROTOCOL`, the highest protocol
+ version will be used.
+
+ .. versionchanged:: 2.3
+ Introduced the *protocol* parameter.
+
+ *file* must have a :meth:`write` method that accepts a single string argument.
+ It can thus be a file object opened for writing, a :mod:`StringIO` object, or
+ any other custom object that meets this interface.
+
+
+.. function:: load(file)
+
+ Read a string from the open file object *file* and interpret it as a pickle data
+ stream, reconstructing and returning the original object hierarchy. This is
+ equivalent to ``Unpickler(file).load()``.
+
+ *file* must have two methods, a :meth:`read` method that takes an integer
+ argument, and a :meth:`readline` method that requires no arguments. Both
+ methods should return a string. Thus *file* can be a file object opened for
+ reading, a :mod:`StringIO` object, or any other custom object that meets this
+ interface.
+
+ This function automatically determines whether the data stream was written in
+ binary mode or not.
+
+
+.. function:: dumps(obj[, protocol])
+
+ Return the pickled representation of the object as a string, instead of writing
+ it to a file.
+
+ If the *protocol* parameter is omitted, protocol 0 is used. If *protocol* is
+ specified as a negative value or :const:`HIGHEST_PROTOCOL`, the highest protocol
+ version will be used.
+
+ .. versionchanged:: 2.3
+ The *protocol* parameter was added.
+
+
+.. function:: loads(string)
+
+ Read a pickled object hierarchy from a string. Characters in the string past
+ the pickled object's representation are ignored.
+
+The :mod:`pickle` module also defines three exceptions:
+
+
+.. exception:: PickleError
+
+ A common base class for the other exceptions defined below. This inherits from
+ :exc:`Exception`.
+
+
+.. exception:: PicklingError
+
+ This exception is raised when an unpicklable object is passed to the
+ :meth:`dump` method.
+
+
+.. exception:: UnpicklingError
+
+ This exception is raised when there is a problem unpickling an object. Note that
+ other exceptions may also be raised during unpickling, including (but not
+ necessarily limited to) :exc:`AttributeError`, :exc:`EOFError`,
+ :exc:`ImportError`, and :exc:`IndexError`.
+
+The :mod:`pickle` module also exports two callables [#]_, :class:`Pickler` and
+:class:`Unpickler`:
+
+
+.. class:: Pickler(file[, protocol])
+
+ This takes a file-like object to which it will write a pickle data stream.
+
+ If the *protocol* parameter is omitted, protocol 0 is used. If *protocol* is
+ specified as a negative value or :const:`HIGHEST_PROTOCOL`, the highest
+ protocol version will be used.
+
+ .. versionchanged:: 2.3
+ Introduced the *protocol* parameter.
+
+ *file* must have a :meth:`write` method that accepts a single string argument.
+ It can thus be an open file object, a :mod:`StringIO` object, or any other
+ custom object that meets this interface.
+
+:class:`Pickler` objects define one (or two) public methods:
+
+
+.. method:: Pickler.dump(obj)
+
+ Write a pickled representation of *obj* to the open file object given in the
+ constructor. Either the binary or ASCII format will be used, depending on the
+ value of the *protocol* argument passed to the constructor.
+
+
+.. method:: Pickler.clear_memo()
+
+ Clears the pickler's "memo". The memo is the data structure that remembers
+ which objects the pickler has already seen, so that shared or recursive objects
+ pickled by reference and not by value. This method is useful when re-using
+ picklers.
+
+ .. note::
+
+ Prior to Python 2.3, :meth:`clear_memo` was only available on the picklers
+ created by :mod:`cPickle`. In the :mod:`pickle` module, picklers have an
+ instance variable called :attr:`memo` which is a Python dictionary. So to clear
+ the memo for a :mod:`pickle` module pickler, you could do the following::
+
+ mypickler.memo.clear()
+
+ Code that does not need to support older versions of Python should simply use
+ :meth:`clear_memo`.
+
+It is possible to make multiple calls to the :meth:`dump` method of the same
+:class:`Pickler` instance. These must then be matched to the same number of
+calls to the :meth:`load` method of the corresponding :class:`Unpickler`
+instance. If the same object is pickled by multiple :meth:`dump` calls, the
+:meth:`load` will all yield references to the same object. [#]_
+
+:class:`Unpickler` objects are defined as:
+
+
+.. class:: Unpickler(file)
+
+ This takes a file-like object from which it will read a pickle data stream.
+ This class automatically determines whether the data stream was written in
+ binary mode or not, so it does not need a flag as in the :class:`Pickler`
+ factory.
+
+ *file* must have two methods, a :meth:`read` method that takes an integer
+ argument, and a :meth:`readline` method that requires no arguments. Both
+ methods should return a string. Thus *file* can be a file object opened for
+ reading, a :mod:`StringIO` object, or any other custom object that meets this
+ interface.
+
+:class:`Unpickler` objects have one (or two) public methods:
+
+
+.. method:: Unpickler.load()
+
+ Read a pickled object representation from the open file object given in the
+ constructor, and return the reconstituted object hierarchy specified therein.
+
+ This method automatically determines whether the data stream was written in
+ binary mode or not.
+
+
+.. method:: Unpickler.noload()
+
+ This is just like :meth:`load` except that it doesn't actually create any
+ objects. This is useful primarily for finding what's called "persistent ids"
+ that may be referenced in a pickle data stream. See section
+ :ref:`pickle-protocol` below for more details.
+
+ **Note:** the :meth:`noload` method is currently only available on
+ :class:`Unpickler` objects created with the :mod:`cPickle` module.
+ :mod:`pickle` module :class:`Unpickler`\ s do not have the :meth:`noload`
+ method.
+
+
+What can be pickled and unpickled?
+----------------------------------
+
+The following types can be pickled:
+
+* ``None``, ``True``, and ``False``
+
+* integers, long integers, floating point numbers, complex numbers
+
+* normal and Unicode strings
+
+* tuples, lists, sets, and dictionaries containing only picklable objects
+
+* functions defined at the top level of a module
+
+* built-in functions defined at the top level of a module
+
+* classes that are defined at the top level of a module
+
+* instances of such classes whose :attr:`__dict__` or :meth:`__setstate__` is
+ picklable (see section :ref:`pickle-protocol` for details)
+
+Attempts to pickle unpicklable objects will raise the :exc:`PicklingError`
+exception; when this happens, an unspecified number of bytes may have already
+been written to the underlying file. Trying to pickle a highly recursive data
+structure may exceed the maximum recursion depth, a :exc:`RuntimeError` will be
+raised in this case. You can carefully raise this limit with
+:func:`sys.setrecursionlimit`.
+
+Note that functions (built-in and user-defined) are pickled by "fully qualified"
+name reference, not by value. This means that only the function name is
+pickled, along with the name of module the function is defined in. Neither the
+function's code, nor any of its function attributes are pickled. Thus the
+defining module must be importable in the unpickling environment, and the module
+must contain the named object, otherwise an exception will be raised. [#]_
+
+Similarly, classes are pickled by named reference, so the same restrictions in
+the unpickling environment apply. Note that none of the class's code or data is
+pickled, so in the following example the class attribute ``attr`` is not
+restored in the unpickling environment::
+
+ class Foo:
+ attr = 'a class attr'
+
+ picklestring = pickle.dumps(Foo)
+
+These restrictions are why picklable functions and classes must be defined in
+the top level of a module.
+
+Similarly, when class instances are pickled, their class's code and data are not
+pickled along with them. Only the instance data are pickled. This is done on
+purpose, so you can fix bugs in a class or add methods to the class and still
+load objects that were created with an earlier version of the class. If you
+plan to have long-lived objects that will see many versions of a class, it may
+be worthwhile to put a version number in the objects so that suitable
+conversions can be made by the class's :meth:`__setstate__` method.
+
+
+.. _pickle-protocol:
+
+The pickle protocol
+-------------------
+
+This section describes the "pickling protocol" that defines the interface
+between the pickler/unpickler and the objects that are being serialized. This
+protocol provides a standard way for you to define, customize, and control how
+your objects are serialized and de-serialized. The description in this section
+doesn't cover specific customizations that you can employ to make the unpickling
+environment slightly safer from untrusted pickle data streams; see section
+:ref:`pickle-sub` for more details.
+
+
+.. _pickle-inst:
+
+Pickling and unpickling normal class instances
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. index::
+ single: __getinitargs__() (copy protocol)
+ single: __init__() (instance constructor)
+
+When a pickled class instance is unpickled, its :meth:`__init__` method is
+normally *not* invoked. If it is desirable that the :meth:`__init__` method be
+called on unpickling, an old-style class can define a method
+:meth:`__getinitargs__`, which should return a *tuple* containing the arguments
+to be passed to the class constructor (:meth:`__init__` for example). The
+:meth:`__getinitargs__` method is called at pickle time; the tuple it returns is
+incorporated in the pickle for the instance.
+
+.. index:: single: __getnewargs__() (copy protocol)
+
+New-style types can provide a :meth:`__getnewargs__` method that is used for
+protocol 2. Implementing this method is needed if the type establishes some
+internal invariants when the instance is created, or if the memory allocation is
+affected by the values passed to the :meth:`__new__` method for the type (as it
+is for tuples and strings). Instances of a new-style type :class:`C` are
+created using ::
+
+ obj = C.__new__(C, *args)
+
+
+where *args* is the result of calling :meth:`__getnewargs__` on the original
+object; if there is no :meth:`__getnewargs__`, an empty tuple is assumed.
+
+.. index::
+ single: __getstate__() (copy protocol)
+ single: __setstate__() (copy protocol)
+ single: __dict__ (instance attribute)
+
+Classes can further influence how their instances are pickled; if the class
+defines the method :meth:`__getstate__`, it is called and the return state is
+pickled as the contents for the instance, instead of the contents of the
+instance's dictionary. If there is no :meth:`__getstate__` method, the
+instance's :attr:`__dict__` is pickled.
+
+Upon unpickling, if the class also defines the method :meth:`__setstate__`, it
+is called with the unpickled state. [#]_ If there is no :meth:`__setstate__`
+method, the pickled state must be a dictionary and its items are assigned to the
+new instance's dictionary. If a class defines both :meth:`__getstate__` and
+:meth:`__setstate__`, the state object needn't be a dictionary and these methods
+can do what they want. [#]_
+
+.. warning::
+
+ For new-style classes, if :meth:`__getstate__` returns a false value, the
+ :meth:`__setstate__` method will not be called.
+
+
+Pickling and unpickling extension types
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When the :class:`Pickler` encounters an object of a type it knows nothing about
+--- such as an extension type --- it looks in two places for a hint of how to
+pickle it. One alternative is for the object to implement a :meth:`__reduce__`
+method. If provided, at pickling time :meth:`__reduce__` will be called with no
+arguments, and it must return either a string or a tuple.
+
+If a string is returned, it names a global variable whose contents are pickled
+as normal. The string returned by :meth:`__reduce__` should be the object's
+local name relative to its module; the pickle module searches the module
+namespace to determine the object's module.
+
+When a tuple is returned, it must be between two and five elements long.
+Optional elements can either be omitted, or ``None`` can be provided as their
+value. The semantics of each element are:
+
+* A callable object that will be called to create the initial version of the
+ object. The next element of the tuple will provide arguments for this callable,
+ and later elements provide additional state information that will subsequently
+ be used to fully reconstruct the pickled data.
+
+ In the unpickling environment this object must be either a class, a callable
+ registered as a "safe constructor" (see below), or it must have an attribute
+ :attr:`__safe_for_unpickling__` with a true value. Otherwise, an
+ :exc:`UnpicklingError` will be raised in the unpickling environment. Note that
+ as usual, the callable itself is pickled by name.
+
+* A tuple of arguments for the callable object.
+
+ .. versionchanged:: 2.5
+ Formerly, this argument could also be ``None``.
+
+* Optionally, the object's state, which will be passed to the object's
+ :meth:`__setstate__` method as described in section :ref:`pickle-inst`. If the
+ object has no :meth:`__setstate__` method, then, as above, the value must be a
+ dictionary and it will be added to the object's :attr:`__dict__`.
+
+* Optionally, an iterator (and not a sequence) yielding successive list items.
+ These list items will be pickled, and appended to the object using either
+ ``obj.append(item)`` or ``obj.extend(list_of_items)``. This is primarily used
+ for list subclasses, but may be used by other classes as long as they have
+ :meth:`append` and :meth:`extend` methods with the appropriate signature.
+ (Whether :meth:`append` or :meth:`extend` is used depends on which pickle
+ protocol version is used as well as the number of items to append, so both must
+ be supported.)
+
+* Optionally, an iterator (not a sequence) yielding successive dictionary items,
+ which should be tuples of the form ``(key, value)``. These items will be
+ pickled and stored to the object using ``obj[key] = value``. This is primarily
+ used for dictionary subclasses, but may be used by other classes as long as they
+ implement :meth:`__setitem__`.
+
+It is sometimes useful to know the protocol version when implementing
+:meth:`__reduce__`. This can be done by implementing a method named
+:meth:`__reduce_ex__` instead of :meth:`__reduce__`. :meth:`__reduce_ex__`, when
+it exists, is called in preference over :meth:`__reduce__` (you may still
+provide :meth:`__reduce__` for backwards compatibility). The
+:meth:`__reduce_ex__` method will be called with a single integer argument, the
+protocol version.
+
+The :class:`object` class implements both :meth:`__reduce__` and
+:meth:`__reduce_ex__`; however, if a subclass overrides :meth:`__reduce__` but
+not :meth:`__reduce_ex__`, the :meth:`__reduce_ex__` implementation detects this
+and calls :meth:`__reduce__`.
+
+An alternative to implementing a :meth:`__reduce__` method on the object to be
+pickled, is to register the callable with the :mod:`copy_reg` module. This
+module provides a way for programs to register "reduction functions" and
+constructors for user-defined types. Reduction functions have the same
+semantics and interface as the :meth:`__reduce__` method described above, except
+that they are called with a single argument, the object to be pickled.
+
+The registered constructor is deemed a "safe constructor" for purposes of
+unpickling as described above.
+
+
+Pickling and unpickling external objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+For the benefit of object persistence, the :mod:`pickle` module supports the
+notion of a reference to an object outside the pickled data stream. Such
+objects are referenced by a "persistent id", which is just an arbitrary string
+of printable ASCII characters. The resolution of such names is not defined by
+the :mod:`pickle` module; it will delegate this resolution to user defined
+functions on the pickler and unpickler. [#]_
+
+To define external persistent id resolution, you need to set the
+:attr:`persistent_id` attribute of the pickler object and the
+:attr:`persistent_load` attribute of the unpickler object.
+
+To pickle objects that have an external persistent id, the pickler must have a
+custom :func:`persistent_id` method that takes an object as an argument and
+returns either ``None`` or the persistent id for that object. When ``None`` is
+returned, the pickler simply pickles the object as normal. When a persistent id
+string is returned, the pickler will pickle that string, along with a marker so
+that the unpickler will recognize the string as a persistent id.
+
+To unpickle external objects, the unpickler must have a custom
+:func:`persistent_load` function that takes a persistent id string and returns
+the referenced object.
+
+Here's a silly example that *might* shed more light::
+
+ import pickle
+ from cStringIO import StringIO
+
+ src = StringIO()
+ p = pickle.Pickler(src)
+
+ def persistent_id(obj):
+ if hasattr(obj, 'x'):
+ return 'the value %d' % obj.x
+ else:
+ return None
+
+ p.persistent_id = persistent_id
+
+ class Integer:
+ def __init__(self, x):
+ self.x = x
+ def __str__(self):
+ return 'My name is integer %d' % self.x
+
+ i = Integer(7)
+ print i
+ p.dump(i)
+
+ datastream = src.getvalue()
+ print repr(datastream)
+ dst = StringIO(datastream)
+
+ up = pickle.Unpickler(dst)
+
+ class FancyInteger(Integer):
+ def __str__(self):
+ return 'I am the integer %d' % self.x
+
+ def persistent_load(persid):
+ if persid.startswith('the value '):
+ value = int(persid.split()[2])
+ return FancyInteger(value)
+ else:
+ raise pickle.UnpicklingError, 'Invalid persistent id'
+
+ up.persistent_load = persistent_load
+
+ j = up.load()
+ print j
+
+In the :mod:`cPickle` module, the unpickler's :attr:`persistent_load` attribute
+can also be set to a Python list, in which case, when the unpickler reaches a
+persistent id, the persistent id string will simply be appended to this list.
+This functionality exists so that a pickle data stream can be "sniffed" for
+object references without actually instantiating all the objects in a pickle.
+[#]_ Setting :attr:`persistent_load` to a list is usually used in conjunction
+with the :meth:`noload` method on the Unpickler.
+
+.. % BAW: Both pickle and cPickle support something called
+.. % inst_persistent_id() which appears to give unknown types a second
+.. % shot at producing a persistent id. Since Jim Fulton can't remember
+.. % why it was added or what it's for, I'm leaving it undocumented.
+
+
+.. _pickle-sub:
+
+Subclassing Unpicklers
+----------------------
+
+By default, unpickling will import any class that it finds in the pickle data.
+You can control exactly what gets unpickled and what gets called by customizing
+your unpickler. Unfortunately, exactly how you do this is different depending
+on whether you're using :mod:`pickle` or :mod:`cPickle`. [#]_
+
+In the :mod:`pickle` module, you need to derive a subclass from
+:class:`Unpickler`, overriding the :meth:`load_global` method.
+:meth:`load_global` should read two lines from the pickle data stream where the
+first line will the name of the module containing the class and the second line
+will be the name of the instance's class. It then looks up the class, possibly
+importing the module and digging out the attribute, then it appends what it
+finds to the unpickler's stack. Later on, this class will be assigned to the
+:attr:`__class__` attribute of an empty class, as a way of magically creating an
+instance without calling its class's :meth:`__init__`. Your job (should you
+choose to accept it), would be to have :meth:`load_global` push onto the
+unpickler's stack, a known safe version of any class you deem safe to unpickle.
+It is up to you to produce such a class. Or you could raise an error if you
+want to disallow all unpickling of instances. If this sounds like a hack,
+you're right. Refer to the source code to make this work.
+
+Things are a little cleaner with :mod:`cPickle`, but not by much. To control
+what gets unpickled, you can set the unpickler's :attr:`find_global` attribute
+to a function or ``None``. If it is ``None`` then any attempts to unpickle
+instances will raise an :exc:`UnpicklingError`. If it is a function, then it
+should accept a module name and a class name, and return the corresponding class
+object. It is responsible for looking up the class and performing any necessary
+imports, and it may raise an error to prevent instances of the class from being
+unpickled.
+
+The moral of the story is that you should be really careful about the source of
+the strings your application unpickles.
+
+
+.. _pickle-example:
+
+Example
+-------
+
+For the simplest code, use the :func:`dump` and :func:`load` functions. Note
+that a self-referencing list is pickled and restored correctly. ::
+
+ import pickle
+
+ data1 = {'a': [1, 2.0, 3, 4+6j],
+ 'b': ('string', u'Unicode string'),
+ 'c': None}
+
+ selfref_list = [1, 2, 3]
+ selfref_list.append(selfref_list)
+
+ output = open('data.pkl', 'wb')
+
+ # Pickle dictionary using protocol 0.
+ pickle.dump(data1, output)
+
+ # Pickle the list using the highest protocol available.
+ pickle.dump(selfref_list, output, -1)
+
+ output.close()
+
+The following example reads the resulting pickled data. When reading a
+pickle-containing file, you should open the file in binary mode because you
+can't be sure if the ASCII or binary format was used. ::
+
+ import pprint, pickle
+
+ pkl_file = open('data.pkl', 'rb')
+
+ data1 = pickle.load(pkl_file)
+ pprint.pprint(data1)
+
+ data2 = pickle.load(pkl_file)
+ pprint.pprint(data2)
+
+ pkl_file.close()
+
+Here's a larger example that shows how to modify pickling behavior for a class.
+The :class:`TextReader` class opens a text file, and returns the line number and
+line contents each time its :meth:`readline` method is called. If a
+:class:`TextReader` instance is pickled, all attributes *except* the file object
+member are saved. When the instance is unpickled, the file is reopened, and
+reading resumes from the last location. The :meth:`__setstate__` and
+:meth:`__getstate__` methods are used to implement this behavior. ::
+
+ #!/usr/local/bin/python
+
+ class TextReader:
+ """Print and number lines in a text file."""
+ def __init__(self, file):
+ self.file = file
+ self.fh = open(file)
+ self.lineno = 0
+
+ def readline(self):
+ self.lineno = self.lineno + 1
+ line = self.fh.readline()
+ if not line:
+ return None
+ if line.endswith("\n"):
+ line = line[:-1]
+ return "%d: %s" % (self.lineno, line)
+
+ def __getstate__(self):
+ odict = self.__dict__.copy() # copy the dict since we change it
+ del odict['fh'] # remove filehandle entry
+ return odict
+
+ def __setstate__(self, dict):
+ fh = open(dict['file']) # reopen file
+ count = dict['lineno'] # read from file...
+ while count: # until line count is restored
+ fh.readline()
+ count = count - 1
+ self.__dict__.update(dict) # update attributes
+ self.fh = fh # save the file object
+
+A sample usage might be something like this::
+
+ >>> import TextReader
+ >>> obj = TextReader.TextReader("TextReader.py")
+ >>> obj.readline()
+ '1: #!/usr/local/bin/python'
+ >>> obj.readline()
+ '2: '
+ >>> obj.readline()
+ '3: class TextReader:'
+ >>> import pickle
+ >>> pickle.dump(obj, open('save.p', 'wb'))
+
+If you want to see that :mod:`pickle` works across Python processes, start
+another Python session, before continuing. What follows can happen from either
+the same process or a new process. ::
+
+ >>> import pickle
+ >>> reader = pickle.load(open('save.p', 'rb'))
+ >>> reader.readline()
+ '4: """Print and number lines in a text file."""'
+
+
+.. seealso::
+
+ Module :mod:`copy_reg`
+ Pickle interface constructor registration for extension types.
+
+ Module :mod:`shelve`
+ Indexed databases of objects; uses :mod:`pickle`.
+
+ Module :mod:`copy`
+ Shallow and deep object copying.
+
+ Module :mod:`marshal`
+ High-performance serialization of built-in types.
+
+
+:mod:`cPickle` --- A faster :mod:`pickle`
+=========================================
+
+.. module:: cPickle
+ :synopsis: Faster version of pickle, but not subclassable.
+.. moduleauthor:: Jim Fulton <jim@zope.com>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. index:: module: pickle
+
+The :mod:`cPickle` module supports serialization and de-serialization of Python
+objects, providing an interface and functionality nearly identical to the
+:mod:`pickle` module. There are several differences, the most important being
+performance and subclassability.
+
+First, :mod:`cPickle` can be up to 1000 times faster than :mod:`pickle` because
+the former is implemented in C. Second, in the :mod:`cPickle` module the
+callables :func:`Pickler` and :func:`Unpickler` are functions, not classes.
+This means that you cannot use them to derive custom pickling and unpickling
+subclasses. Most applications have no need for this functionality and should
+benefit from the greatly improved performance of the :mod:`cPickle` module.
+
+The pickle data stream produced by :mod:`pickle` and :mod:`cPickle` are
+identical, so it is possible to use :mod:`pickle` and :mod:`cPickle`
+interchangeably with existing pickles. [#]_
+
+There are additional minor differences in API between :mod:`cPickle` and
+:mod:`pickle`, however for most applications, they are interchangeable. More
+documentation is provided in the :mod:`pickle` module documentation, which
+includes a list of the documented differences.
+
+.. rubric:: Footnotes
+
+.. [#] Don't confuse this with the :mod:`marshal` module
+
+.. [#] In the :mod:`pickle` module these callables are classes, which you could
+ subclass to customize the behavior. However, in the :mod:`cPickle` module these
+ callables are factory functions and so cannot be subclassed. One common reason
+ to subclass is to control what objects can actually be unpickled. See section
+ :ref:`pickle-sub` for more details.
+
+.. [#] *Warning*: this is intended for pickling multiple objects without intervening
+ modifications to the objects or their parts. If you modify an object and then
+ pickle it again using the same :class:`Pickler` instance, the object is not
+ pickled again --- a reference to it is pickled and the :class:`Unpickler` will
+ return the old value, not the modified one. There are two problems here: (1)
+ detecting changes, and (2) marshalling a minimal set of changes. Garbage
+ Collection may also become a problem here.
+
+.. [#] The exception raised will likely be an :exc:`ImportError` or an
+ :exc:`AttributeError` but it could be something else.
+
+.. [#] These methods can also be used to implement copying class instances.
+
+.. [#] This protocol is also used by the shallow and deep copying operations defined in
+ the :mod:`copy` module.
+
+.. [#] The actual mechanism for associating these user defined functions is slightly
+ different for :mod:`pickle` and :mod:`cPickle`. The description given here
+ works the same for both implementations. Users of the :mod:`pickle` module
+ could also use subclassing to effect the same results, overriding the
+ :meth:`persistent_id` and :meth:`persistent_load` methods in the derived
+ classes.
+
+.. [#] We'll leave you with the image of Guido and Jim sitting around sniffing pickles
+ in their living rooms.
+
+.. [#] A word of caution: the mechanisms described here use internal attributes and
+ methods, which are subject to change in future versions of Python. We intend to
+ someday provide a common interface for controlling this behavior, which will
+ work in either :mod:`pickle` or :mod:`cPickle`.
+
+.. [#] Since the pickle data format is actually a tiny stack-oriented programming
+ language, and some freedom is taken in the encodings of certain objects, it is
+ possible that the two modules produce different data streams for the same input
+ objects. However it is guaranteed that they will always be able to read each
+ other's data streams.
+
diff --git a/Doc/library/pickletools.rst b/Doc/library/pickletools.rst
new file mode 100644
index 0000000000..ec220d960d
--- /dev/null
+++ b/Doc/library/pickletools.rst
@@ -0,0 +1,37 @@
+
+:mod:`pickletools` --- Tools for pickle developers.
+===================================================
+
+.. module:: pickletools
+ :synopsis: Contains extensive comments about the pickle protocols and pickle-machine
+ opcodes, as well as some useful functions.
+
+
+.. versionadded:: 2.3
+
+This module contains various constants relating to the intimate details of the
+:mod:`pickle` module, some lengthy comments about the implementation, and a few
+useful functions for analyzing pickled data. The contents of this module are
+useful for Python core developers who are working on the :mod:`pickle` and
+:mod:`cPickle` implementations; ordinary users of the :mod:`pickle` module
+probably won't find the :mod:`pickletools` module relevant.
+
+
+.. function:: dis(pickle[, out=None, memo=None, indentlevel=4])
+
+ Outputs a symbolic disassembly of the pickle to the file-like object *out*,
+ defaulting to ``sys.stdout``. *pickle* can be a string or a file-like object.
+ *memo* can be a Python dictionary that will be used as the pickle's memo; it can
+ be used to perform disassemblies across multiple pickles created by the same
+ pickler. Successive levels, indicated by ``MARK`` opcodes in the stream, are
+ indented by *indentlevel* spaces.
+
+
+.. function:: genops(pickle)
+
+ Provides an iterator over all of the opcodes in a pickle, returning a sequence
+ of ``(opcode, arg, pos)`` triples. *opcode* is an instance of an
+ :class:`OpcodeInfo` class; *arg* is the decoded value, as a Python object, of
+ the opcode's argument; *pos* is the position at which this opcode is located.
+ *pickle* can be a string or a file-like object.
+
diff --git a/Doc/library/pipes.rst b/Doc/library/pipes.rst
new file mode 100644
index 0000000000..1f2b2ff239
--- /dev/null
+++ b/Doc/library/pipes.rst
@@ -0,0 +1,92 @@
+
+:mod:`pipes` --- Interface to shell pipelines
+=============================================
+
+.. module:: pipes
+ :platform: Unix
+ :synopsis: A Python interface to Unix shell pipelines.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`pipes` module defines a class to abstract the concept of a *pipeline*
+--- a sequence of converters from one file to another.
+
+Because the module uses :program:`/bin/sh` command lines, a POSIX or compatible
+shell for :func:`os.system` and :func:`os.popen` is required.
+
+The :mod:`pipes` module defines the following class:
+
+
+.. class:: Template()
+
+ An abstraction of a pipeline.
+
+Example::
+
+ >>> import pipes
+ >>> t=pipes.Template()
+ >>> t.append('tr a-z A-Z', '--')
+ >>> f=t.open('/tmp/1', 'w')
+ >>> f.write('hello world')
+ >>> f.close()
+ >>> open('/tmp/1').read()
+ 'HELLO WORLD'
+
+
+.. _template-objects:
+
+Template Objects
+----------------
+
+Template objects following methods:
+
+
+.. method:: Template.reset()
+
+ Restore a pipeline template to its initial state.
+
+
+.. method:: Template.clone()
+
+ Return a new, equivalent, pipeline template.
+
+
+.. method:: Template.debug(flag)
+
+ If *flag* is true, turn debugging on. Otherwise, turn debugging off. When
+ debugging is on, commands to be executed are printed, and the shell is given
+ ``set -x`` command to be more verbose.
+
+
+.. method:: Template.append(cmd, kind)
+
+ Append a new action at the end. The *cmd* variable must be a valid bourne shell
+ command. The *kind* variable consists of two letters.
+
+ The first letter can be either of ``'-'`` (which means the command reads its
+ standard input), ``'f'`` (which means the commands reads a given file on the
+ command line) or ``'.'`` (which means the commands reads no input, and hence
+ must be first.)
+
+ Similarly, the second letter can be either of ``'-'`` (which means the command
+ writes to standard output), ``'f'`` (which means the command writes a file on
+ the command line) or ``'.'`` (which means the command does not write anything,
+ and hence must be last.)
+
+
+.. method:: Template.prepend(cmd, kind)
+
+ Add a new action at the beginning. See :meth:`append` for explanations of the
+ arguments.
+
+
+.. method:: Template.open(file, mode)
+
+ Return a file-like object, open to *file*, but read from or written to by the
+ pipeline. Note that only one of ``'r'``, ``'w'`` may be given.
+
+
+.. method:: Template.copy(infile, outfile)
+
+ Copy *infile* to *outfile* through the pipe.
+
diff --git a/Doc/library/pkgutil.rst b/Doc/library/pkgutil.rst
new file mode 100644
index 0000000000..1fbfb041dc
--- /dev/null
+++ b/Doc/library/pkgutil.rst
@@ -0,0 +1,43 @@
+
+:mod:`pkgutil` --- Package extension utility
+============================================
+
+.. module:: pkgutil
+ :synopsis: Utilities to support extension of packages.
+
+
+.. versionadded:: 2.3
+
+This module provides a single function:
+
+
+.. function:: extend_path(path, name)
+
+ Extend the search path for the modules which comprise a package. Intended use is
+ to place the following code in a package's :file:`__init__.py`::
+
+ from pkgutil import extend_path
+ __path__ = extend_path(__path__, __name__)
+
+ This will add to the package's ``__path__`` all subdirectories of directories on
+ ``sys.path`` named after the package. This is useful if one wants to distribute
+ different parts of a single logical package as multiple directories.
+
+ It also looks for :file:`\*.pkg` files beginning where ``*`` matches the *name*
+ argument. This feature is similar to :file:`\*.pth` files (see the :mod:`site`
+ module for more information), except that it doesn't special-case lines starting
+ with ``import``. A :file:`\*.pkg` file is trusted at face value: apart from
+ checking for duplicates, all entries found in a :file:`\*.pkg` file are added to
+ the path, regardless of whether they exist on the filesystem. (This is a
+ feature.)
+
+ If the input path is not a list (as is the case for frozen packages) it is
+ returned unchanged. The input path is not modified; an extended copy is
+ returned. Items are only appended to the copy at the end.
+
+ It is assumed that ``sys.path`` is a sequence. Items of ``sys.path`` that are
+ not (Unicode or 8-bit) strings referring to existing directories are ignored.
+ Unicode items on ``sys.path`` that cause errors when used as filenames may cause
+ this function to raise an exception (in line with :func:`os.path.isdir`
+ behavior).
+
diff --git a/Doc/library/platform.rst b/Doc/library/platform.rst
new file mode 100644
index 0000000000..a4570d2591
--- /dev/null
+++ b/Doc/library/platform.rst
@@ -0,0 +1,256 @@
+
+:mod:`platform` --- Access to underlying platform's identifying data.
+======================================================================
+
+.. module:: platform
+ :synopsis: Retrieves as much platform identifying data as possible.
+.. moduleauthor:: Marc-Andre Lemburg <mal@egenix.com>
+.. sectionauthor:: Bjorn Pettersen <bpettersen@corp.fairisaac.com>
+
+
+.. versionadded:: 2.3
+
+.. note::
+
+ Specific platforms listed alphabetically, with Linux included in the Unix
+ section.
+
+
+Cross Platform
+--------------
+
+
+.. function:: architecture(executable=sys.executable, bits='', linkage='')
+
+ Queries the given executable (defaults to the Python interpreter binary) for
+ various architecture information.
+
+ Returns a tuple ``(bits, linkage)`` which contain information about the bit
+ architecture and the linkage format used for the executable. Both values are
+ returned as strings.
+
+ Values that cannot be determined are returned as given by the parameter presets.
+ If bits is given as ``''``, the :cfunc:`sizeof(pointer)` (or
+ :cfunc:`sizeof(long)` on Python version < 1.5.2) is used as indicator for the
+ supported pointer size.
+
+ The function relies on the system's :file:`file` command to do the actual work.
+ This is available on most if not all Unix platforms and some non-Unix platforms
+ and then only if the executable points to the Python interpreter. Reasonable
+ defaults are used when the above needs are not met.
+
+
+.. function:: machine()
+
+ Returns the machine type, e.g. ``'i386'``. An empty string is returned if the
+ value cannot be determined.
+
+
+.. function:: node()
+
+ Returns the computer's network name (may not be fully qualified!). An empty
+ string is returned if the value cannot be determined.
+
+
+.. function:: platform(aliased=0, terse=0)
+
+ Returns a single string identifying the underlying platform with as much useful
+ information as possible.
+
+ The output is intended to be *human readable* rather than machine parseable. It
+ may look different on different platforms and this is intended.
+
+ If *aliased* is true, the function will use aliases for various platforms that
+ report system names which differ from their common names, for example SunOS will
+ be reported as Solaris. The :func:`system_alias` function is used to implement
+ this.
+
+ Setting *terse* to true causes the function to return only the absolute minimum
+ information needed to identify the platform.
+
+
+.. function:: processor()
+
+ Returns the (real) processor name, e.g. ``'amdk6'``.
+
+ An empty string is returned if the value cannot be determined. Note that many
+ platforms do not provide this information or simply return the same value as for
+ :func:`machine`. NetBSD does this.
+
+
+.. function:: python_build()
+
+ Returns a tuple ``(buildno, builddate)`` stating the Python build number and
+ date as strings.
+
+
+.. function:: python_compiler()
+
+ Returns a string identifying the compiler used for compiling Python.
+
+
+.. function:: python_branch()
+
+ Returns a string identifying the Python implementation SCM branch.
+
+ .. versionadded:: 2.6
+
+
+.. function:: python_implementation()
+
+ Returns a string identifying the Python implementation. Possible return values
+ are: 'CPython', 'IronPython', 'Jython'
+
+ .. versionadded:: 2.6
+
+
+.. function:: python_revision()
+
+ Returns a string identifying the Python implementation SCM revision.
+
+ .. versionadded:: 2.6
+
+
+.. function:: python_version()
+
+ Returns the Python version as string ``'major.minor.patchlevel'``
+
+ Note that unlike the Python ``sys.version``, the returned value will always
+ include the patchlevel (it defaults to 0).
+
+
+.. function:: python_version_tuple()
+
+ Returns the Python version as tuple ``(major, minor, patchlevel)`` of strings.
+
+ Note that unlike the Python ``sys.version``, the returned value will always
+ include the patchlevel (it defaults to ``'0'``).
+
+
+.. function:: release()
+
+ Returns the system's release, e.g. ``'2.2.0'`` or ``'NT'`` An empty string is
+ returned if the value cannot be determined.
+
+
+.. function:: system()
+
+ Returns the system/OS name, e.g. ``'Linux'``, ``'Windows'``, or ``'Java'``. An
+ empty string is returned if the value cannot be determined.
+
+
+.. function:: system_alias(system, release, version)
+
+ Returns ``(system, release, version)`` aliased to common marketing names used
+ for some systems. It also does some reordering of the information in some cases
+ where it would otherwise cause confusion.
+
+
+.. function:: version()
+
+ Returns the system's release version, e.g. ``'#3 on degas'``. An empty string is
+ returned if the value cannot be determined.
+
+
+.. function:: uname()
+
+ Fairly portable uname interface. Returns a tuple of strings ``(system, node,
+ release, version, machine, processor)`` identifying the underlying platform.
+
+ Note that unlike the :func:`os.uname` function this also returns possible
+ processor information as additional tuple entry.
+
+ Entries which cannot be determined are set to ``''``.
+
+
+Java Platform
+-------------
+
+
+.. function:: java_ver(release='', vendor='', vminfo=('','',''), osinfo=('','',''))
+
+ Version interface for JPython.
+
+ Returns a tuple ``(release, vendor, vminfo, osinfo)`` with *vminfo* being a
+ tuple ``(vm_name, vm_release, vm_vendor)`` and *osinfo* being a tuple
+ ``(os_name, os_version, os_arch)``. Values which cannot be determined are set to
+ the defaults given as parameters (which all default to ``''``).
+
+
+Windows Platform
+----------------
+
+
+.. function:: win32_ver(release='', version='', csd='', ptype='')
+
+ Get additional version information from the Windows Registry and return a tuple
+ ``(version, csd, ptype)`` referring to version number, CSD level and OS type
+ (multi/single processor).
+
+ As a hint: *ptype* is ``'Uniprocessor Free'`` on single processor NT machines
+ and ``'Multiprocessor Free'`` on multi processor machines. The *'Free'* refers
+ to the OS version being free of debugging code. It could also state *'Checked'*
+ which means the OS version uses debugging code, i.e. code that checks arguments,
+ ranges, etc.
+
+ .. note::
+
+ This function only works if Mark Hammond's :mod:`win32all` package is installed
+ and (obviously) only runs on Win32 compatible platforms.
+
+
+Win95/98 specific
+^^^^^^^^^^^^^^^^^
+
+
+.. function:: popen(cmd, mode='r', bufsize=None)
+
+ Portable :func:`popen` interface. Find a working popen implementation
+ preferring :func:`win32pipe.popen`. On Windows NT, :func:`win32pipe.popen`
+ should work; on Windows 9x it hangs due to bugs in the MS C library.
+
+ .. % This KnowledgeBase article appears to be missing...
+ .. % See also \ulink{MS KnowledgeBase article Q150956}{}.
+
+
+Mac OS Platform
+---------------
+
+
+.. function:: mac_ver(release='', versioninfo=('','',''), machine='')
+
+ Get Mac OS version information and return it as tuple ``(release, versioninfo,
+ machine)`` with *versioninfo* being a tuple ``(version, dev_stage,
+ non_release_version)``.
+
+ Entries which cannot be determined are set to ``''``. All tuple entries are
+ strings.
+
+ Documentation for the underlying :cfunc:`gestalt` API is available online at
+ http://www.rgaros.nl/gestalt/.
+
+
+Unix Platforms
+--------------
+
+
+.. function:: dist(distname='', version='', id='', supported_dists=('SuSE','debian','redhat','mandrake'))
+
+ Tries to determine the name of the OS distribution name Returns a tuple
+ ``(distname, version, id)`` which defaults to the args given as parameters.
+
+.. % Document linux_distribution()?
+
+
+.. function:: libc_ver(executable=sys.executable, lib='', version='', chunksize=2048)
+
+ Tries to determine the libc version against which the file executable (defaults
+ to the Python interpreter) is linked. Returns a tuple of strings ``(lib,
+ version)`` which default to the given parameters in case the lookup fails.
+
+ Note that this function has intimate knowledge of how different libc versions
+ add symbols to the executable is probably only useable for executables compiled
+ using :program:`gcc`.
+
+ The file is read and scanned in chunks of *chunksize* bytes.
+
diff --git a/Doc/library/poplib.rst b/Doc/library/poplib.rst
new file mode 100644
index 0000000000..5716204324
--- /dev/null
+++ b/Doc/library/poplib.rst
@@ -0,0 +1,202 @@
+
+:mod:`poplib` --- POP3 protocol client
+======================================
+
+.. module:: poplib
+ :synopsis: POP3 protocol client (requires sockets).
+
+
+.. index:: pair: POP3; protocol
+
+.. % By Andrew T. Csillag
+.. % Even though I put it into LaTeX, I cannot really claim that I wrote
+.. % it since I just stole most of it from the poplib.py source code and
+.. % the imaplib ``chapter''.
+.. % Revised by ESR, January 2000
+
+This module defines a class, :class:`POP3`, which encapsulates a connection to a
+POP3 server and implements the protocol as defined in :rfc:`1725`. The
+:class:`POP3` class supports both the minimal and optional command sets.
+Additionally, this module provides a class :class:`POP3_SSL`, which provides
+support for connecting to POP3 servers that use SSL as an underlying protocol
+layer.
+
+Note that POP3, though widely supported, is obsolescent. The implementation
+quality of POP3 servers varies widely, and too many are quite poor. If your
+mailserver supports IMAP, you would be better off using the
+:class:`imaplib.IMAP4` class, as IMAP servers tend to be better implemented.
+
+A single class is provided by the :mod:`poplib` module:
+
+
+.. class:: POP3(host[, port[, timeout]])
+
+ This class implements the actual POP3 protocol. The connection is created when
+ the instance is initialized. If *port* is omitted, the standard POP3 port (110)
+ is used. The optional *timeout* parameter specifies a timeout in seconds for the
+ connection attempt (if not specified, or passed as None, the global default
+ timeout setting will be used).
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. class:: POP3_SSL(host[, port[, keyfile[, certfile]]])
+
+ This is a subclass of :class:`POP3` that connects to the server over an SSL
+ encrypted socket. If *port* is not specified, 995, the standard POP3-over-SSL
+ port is used. *keyfile* and *certfile* are also optional - they can contain a
+ PEM formatted private key and certificate chain file for the SSL connection.
+
+ .. versionadded:: 2.4
+
+One exception is defined as an attribute of the :mod:`poplib` module:
+
+
+.. exception:: error_proto
+
+ Exception raised on any errors from this module (errors from :mod:`socket`
+ module are not caught). The reason for the exception is passed to the
+ constructor as a string.
+
+
+.. seealso::
+
+ Module :mod:`imaplib`
+ The standard Python IMAP module.
+
+ `Frequently Asked Questions About Fetchmail <http://www.catb.org/~esr/fetchmail/fetchmail-FAQ.html>`_
+ The FAQ for the :program:`fetchmail` POP/IMAP client collects information on
+ POP3 server variations and RFC noncompliance that may be useful if you need to
+ write an application based on the POP protocol.
+
+
+.. _pop3-objects:
+
+POP3 Objects
+------------
+
+All POP3 commands are represented by methods of the same name, in lower-case;
+most return the response text sent by the server.
+
+An :class:`POP3` instance has the following methods:
+
+
+.. method:: POP3.set_debuglevel(level)
+
+ Set the instance's debugging level. This controls the amount of debugging
+ output printed. The default, ``0``, produces no debugging output. A value of
+ ``1`` produces a moderate amount of debugging output, generally a single line
+ per request. A value of ``2`` or higher produces the maximum amount of
+ debugging output, logging each line sent and received on the control connection.
+
+
+.. method:: POP3.getwelcome()
+
+ Returns the greeting string sent by the POP3 server.
+
+
+.. method:: POP3.user(username)
+
+ Send user command, response should indicate that a password is required.
+
+
+.. method:: POP3.pass_(password)
+
+ Send password, response includes message count and mailbox size. Note: the
+ mailbox on the server is locked until :meth:`quit` is called.
+
+
+.. method:: POP3.apop(user, secret)
+
+ Use the more secure APOP authentication to log into the POP3 server.
+
+
+.. method:: POP3.rpop(user)
+
+ Use RPOP authentication (similar to UNIX r-commands) to log into POP3 server.
+
+
+.. method:: POP3.stat()
+
+ Get mailbox status. The result is a tuple of 2 integers: ``(message count,
+ mailbox size)``.
+
+
+.. method:: POP3.list([which])
+
+ Request message list, result is in the form ``(response, ['mesg_num octets',
+ ...], octets)``. If *which* is set, it is the message to list.
+
+
+.. method:: POP3.retr(which)
+
+ Retrieve whole message number *which*, and set its seen flag. Result is in form
+ ``(response, ['line', ...], octets)``.
+
+
+.. method:: POP3.dele(which)
+
+ Flag message number *which* for deletion. On most servers deletions are not
+ actually performed until QUIT (the major exception is Eudora QPOP, which
+ deliberately violates the RFCs by doing pending deletes on any disconnect).
+
+
+.. method:: POP3.rset()
+
+ Remove any deletion marks for the mailbox.
+
+
+.. method:: POP3.noop()
+
+ Do nothing. Might be used as a keep-alive.
+
+
+.. method:: POP3.quit()
+
+ Signoff: commit changes, unlock mailbox, drop connection.
+
+
+.. method:: POP3.top(which, howmuch)
+
+ Retrieves the message header plus *howmuch* lines of the message after the
+ header of message number *which*. Result is in form ``(response, ['line', ...],
+ octets)``.
+
+ The POP3 TOP command this method uses, unlike the RETR command, doesn't set the
+ message's seen flag; unfortunately, TOP is poorly specified in the RFCs and is
+ frequently broken in off-brand servers. Test this method by hand against the
+ POP3 servers you will use before trusting it.
+
+
+.. method:: POP3.uidl([which])
+
+ Return message digest (unique id) list. If *which* is specified, result contains
+ the unique id for that message in the form ``'response mesgnum uid``, otherwise
+ result is list ``(response, ['mesgnum uid', ...], octets)``.
+
+Instances of :class:`POP3_SSL` have no additional methods. The interface of this
+subclass is identical to its parent.
+
+
+.. _pop3-example:
+
+POP3 Example
+------------
+
+Here is a minimal example (without error checking) that opens a mailbox and
+retrieves and prints all messages::
+
+ import getpass, poplib
+
+ M = poplib.POP3('localhost')
+ M.user(getpass.getuser())
+ M.pass_(getpass.getpass())
+ numMessages = len(M.list()[1])
+ for i in range(numMessages):
+ for j in M.retr(i+1)[1]:
+ print j
+
+At the end of the module, there is a test section that contains a more extensive
+example of usage.
+
diff --git a/Doc/library/posix.rst b/Doc/library/posix.rst
new file mode 100644
index 0000000000..07ecb48f43
--- /dev/null
+++ b/Doc/library/posix.rst
@@ -0,0 +1,103 @@
+
+:mod:`posix` --- The most common POSIX system calls
+===================================================
+
+.. module:: posix
+ :platform: Unix
+ :synopsis: The most common POSIX system calls (normally used via module os).
+
+
+This module provides access to operating system functionality that is
+standardized by the C Standard and the POSIX standard (a thinly disguised Unix
+interface).
+
+.. index:: module: os
+
+**Do not import this module directly.** Instead, import the module :mod:`os`,
+which provides a *portable* version of this interface. On Unix, the :mod:`os`
+module provides a superset of the :mod:`posix` interface. On non-Unix operating
+systems the :mod:`posix` module is not available, but a subset is always
+available through the :mod:`os` interface. Once :mod:`os` is imported, there is
+*no* performance penalty in using it instead of :mod:`posix`. In addition,
+:mod:`os` provides some additional functionality, such as automatically calling
+:func:`putenv` when an entry in ``os.environ`` is changed.
+
+The descriptions below are very terse; refer to the corresponding Unix manual
+(or POSIX documentation) entry for more information. Arguments called *path*
+refer to a pathname given as a string.
+
+Errors are reported as exceptions; the usual exceptions are given for type
+errors, while errors reported by the system calls raise :exc:`error` (a synonym
+for the standard exception :exc:`OSError`), described below.
+
+
+.. _posix-large-files:
+
+Large File Support
+------------------
+
+.. index::
+ single: large files
+ single: file; large files
+
+.. sectionauthor:: Steve Clift <clift@mail.anacapa.net>
+
+
+Several operating systems (including AIX, HPUX, Irix and Solaris) provide
+support for files that are larger than 2 Gb from a C programming model where
+:ctype:`int` and :ctype:`long` are 32-bit values. This is typically accomplished
+by defining the relevant size and offset types as 64-bit values. Such files are
+sometimes referred to as :dfn:`large files`.
+
+Large file support is enabled in Python when the size of an :ctype:`off_t` is
+larger than a :ctype:`long` and the :ctype:`long long` type is available and is
+at least as large as an :ctype:`off_t`. Python longs are then used to represent
+file sizes, offsets and other values that can exceed the range of a Python int.
+It may be necessary to configure and compile Python with certain compiler flags
+to enable this mode. For example, it is enabled by default with recent versions
+of Irix, but with Solaris 2.6 and 2.7 you need to do something like::
+
+ CFLAGS="`getconf LFS_CFLAGS`" OPT="-g -O2 $CFLAGS" \
+ ./configure
+
+On large-file-capable Linux systems, this might work:
+
+.. % $ <-- bow to font-lock
+
+::
+
+ CFLAGS='-D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64' OPT="-g -O2 $CFLAGS" \
+ ./configure
+
+.. % $ <-- bow to font-lock
+
+
+.. _posix-contents:
+
+Module Contents
+---------------
+
+Module :mod:`posix` defines the following data item:
+
+
+.. data:: environ
+
+ A dictionary representing the string environment at the time the interpreter was
+ started. For example, ``environ['HOME']`` is the pathname of your home
+ directory, equivalent to ``getenv("HOME")`` in C.
+
+ Modifying this dictionary does not affect the string environment passed on by
+ :func:`execv`, :func:`popen` or :func:`system`; if you need to change the
+ environment, pass ``environ`` to :func:`execve` or add variable assignments and
+ export statements to the command string for :func:`system` or :func:`popen`.
+
+ .. note::
+
+ The :mod:`os` module provides an alternate implementation of ``environ`` which
+ updates the environment on modification. Note also that updating ``os.environ``
+ will render this dictionary obsolete. Use of the :mod:`os` module version of
+ this is recommended over direct access to the :mod:`posix` module.
+
+Additional contents of this module should only be accessed via the :mod:`os`
+module; refer to the documentation for that module for further information.
+
diff --git a/Doc/library/pprint.rst b/Doc/library/pprint.rst
new file mode 100644
index 0000000000..36301765c8
--- /dev/null
+++ b/Doc/library/pprint.rst
@@ -0,0 +1,213 @@
+
+:mod:`pprint` --- Data pretty printer
+=====================================
+
+.. module:: pprint
+ :synopsis: Data pretty printer.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`pprint` module provides a capability to "pretty-print" arbitrary
+Python data structures in a form which can be used as input to the interpreter.
+If the formatted structures include objects which are not fundamental Python
+types, the representation may not be loadable. This may be the case if objects
+such as files, sockets, classes, or instances are included, as well as many
+other builtin objects which are not representable as Python constants.
+
+The formatted representation keeps objects on a single line if it can, and
+breaks them onto multiple lines if they don't fit within the allowed width.
+Construct :class:`PrettyPrinter` objects explicitly if you need to adjust the
+width constraint.
+
+.. versionchanged:: 2.5
+ Dictionaries are sorted by key before the display is computed; before 2.5, a
+ dictionary was sorted only if its display required more than one line, although
+ that wasn't documented.
+
+The :mod:`pprint` module defines one class:
+
+.. % First the implementation class:
+
+
+.. class:: PrettyPrinter(...)
+
+ Construct a :class:`PrettyPrinter` instance. This constructor understands
+ several keyword parameters. An output stream may be set using the *stream*
+ keyword; the only method used on the stream object is the file protocol's
+ :meth:`write` method. If not specified, the :class:`PrettyPrinter` adopts
+ ``sys.stdout``. Three additional parameters may be used to control the
+ formatted representation. The keywords are *indent*, *depth*, and *width*. The
+ amount of indentation added for each recursive level is specified by *indent*;
+ the default is one. Other values can cause output to look a little odd, but can
+ make nesting easier to spot. The number of levels which may be printed is
+ controlled by *depth*; if the data structure being printed is too deep, the next
+ contained level is replaced by ``...``. By default, there is no constraint on
+ the depth of the objects being formatted. The desired output width is
+ constrained using the *width* parameter; the default is 80 characters. If a
+ structure cannot be formatted within the constrained width, a best effort will
+ be made. ::
+
+ >>> import pprint, sys
+ >>> stuff = sys.path[:]
+ >>> stuff.insert(0, stuff[:])
+ >>> pp = pprint.PrettyPrinter(indent=4)
+ >>> pp.pprint(stuff)
+ [ [ '',
+ '/usr/local/lib/python1.5',
+ '/usr/local/lib/python1.5/test',
+ '/usr/local/lib/python1.5/sunos5',
+ '/usr/local/lib/python1.5/sharedmodules',
+ '/usr/local/lib/python1.5/tkinter'],
+ '',
+ '/usr/local/lib/python1.5',
+ '/usr/local/lib/python1.5/test',
+ '/usr/local/lib/python1.5/sunos5',
+ '/usr/local/lib/python1.5/sharedmodules',
+ '/usr/local/lib/python1.5/tkinter']
+ >>>
+ >>> import parser
+ >>> tup = parser.ast2tuple(
+ ... parser.suite(open('pprint.py').read()))[1][1][1]
+ >>> pp = pprint.PrettyPrinter(depth=6)
+ >>> pp.pprint(tup)
+ (266, (267, (307, (287, (288, (...))))))
+
+The :class:`PrettyPrinter` class supports several derivative functions:
+
+.. % Now the derivative functions:
+
+
+.. function:: pformat(object[, indent[, width[, depth]]])
+
+ Return the formatted representation of *object* as a string. *indent*, *width*
+ and *depth* will be passed to the :class:`PrettyPrinter` constructor as
+ formatting parameters.
+
+ .. versionchanged:: 2.4
+ The parameters *indent*, *width* and *depth* were added.
+
+
+.. function:: pprint(object[, stream[, indent[, width[, depth]]]])
+
+ Prints the formatted representation of *object* on *stream*, followed by a
+ newline. If *stream* is omitted, ``sys.stdout`` is used. This may be used in
+ the interactive interpreter instead of a :keyword:`print` statement for
+ inspecting values. *indent*, *width* and *depth* will be passed to the
+ :class:`PrettyPrinter` constructor as formatting parameters. ::
+
+ >>> stuff = sys.path[:]
+ >>> stuff.insert(0, stuff)
+ >>> pprint.pprint(stuff)
+ [<Recursion on list with id=869440>,
+ '',
+ '/usr/local/lib/python1.5',
+ '/usr/local/lib/python1.5/test',
+ '/usr/local/lib/python1.5/sunos5',
+ '/usr/local/lib/python1.5/sharedmodules',
+ '/usr/local/lib/python1.5/tkinter']
+
+ .. versionchanged:: 2.4
+ The parameters *indent*, *width* and *depth* were added.
+
+
+.. function:: isreadable(object)
+
+ .. index:: builtin: eval
+
+ Determine if the formatted representation of *object* is "readable," or can be
+ used to reconstruct the value using :func:`eval`. This always returns ``False``
+ for recursive objects. ::
+
+ >>> pprint.isreadable(stuff)
+ False
+
+
+.. function:: isrecursive(object)
+
+ Determine if *object* requires a recursive representation.
+
+One more support function is also defined:
+
+
+.. function:: saferepr(object)
+
+ Return a string representation of *object*, protected against recursive data
+ structures. If the representation of *object* exposes a recursive entry, the
+ recursive reference will be represented as ``<Recursion on typename with
+ id=number>``. The representation is not otherwise formatted.
+
+.. % This example is outside the {funcdesc} to keep it from running over
+.. % the right margin.
+
+::
+
+ >>> pprint.saferepr(stuff)
+ "[<Recursion on list with id=682968>, '', '/usr/local/lib/python1.5', '/usr/loca
+ l/lib/python1.5/test', '/usr/local/lib/python1.5/sunos5', '/usr/local/lib/python
+ 1.5/sharedmodules', '/usr/local/lib/python1.5/tkinter']"
+
+
+.. _prettyprinter-objects:
+
+PrettyPrinter Objects
+---------------------
+
+:class:`PrettyPrinter` instances have the following methods:
+
+
+.. method:: PrettyPrinter.pformat(object)
+
+ Return the formatted representation of *object*. This takes into account the
+ options passed to the :class:`PrettyPrinter` constructor.
+
+
+.. method:: PrettyPrinter.pprint(object)
+
+ Print the formatted representation of *object* on the configured stream,
+ followed by a newline.
+
+The following methods provide the implementations for the corresponding
+functions of the same names. Using these methods on an instance is slightly
+more efficient since new :class:`PrettyPrinter` objects don't need to be
+created.
+
+
+.. method:: PrettyPrinter.isreadable(object)
+
+ .. index:: builtin: eval
+
+ Determine if the formatted representation of the object is "readable," or can be
+ used to reconstruct the value using :func:`eval`. Note that this returns
+ ``False`` for recursive objects. If the *depth* parameter of the
+ :class:`PrettyPrinter` is set and the object is deeper than allowed, this
+ returns ``False``.
+
+
+.. method:: PrettyPrinter.isrecursive(object)
+
+ Determine if the object requires a recursive representation.
+
+This method is provided as a hook to allow subclasses to modify the way objects
+are converted to strings. The default implementation uses the internals of the
+:func:`saferepr` implementation.
+
+
+.. method:: PrettyPrinter.format(object, context, maxlevels, level)
+
+ Returns three values: the formatted version of *object* as a string, a flag
+ indicating whether the result is readable, and a flag indicating whether
+ recursion was detected. The first argument is the object to be presented. The
+ second is a dictionary which contains the :func:`id` of objects that are part of
+ the current presentation context (direct and indirect containers for *object*
+ that are affecting the presentation) as the keys; if an object needs to be
+ presented which is already represented in *context*, the third return value
+ should be ``True``. Recursive calls to the :meth:`format` method should add
+ additional entries for containers to this dictionary. The third argument,
+ *maxlevels*, gives the requested limit to recursion; this will be ``0`` if there
+ is no requested limit. This argument should be passed unmodified to recursive
+ calls. The fourth argument, *level*, gives the current level; recursive calls
+ should be passed a value less than that of the current call.
+
+ .. versionadded:: 2.3
+
diff --git a/Doc/library/profile.rst b/Doc/library/profile.rst
new file mode 100644
index 0000000000..2ab24c56ae
--- /dev/null
+++ b/Doc/library/profile.rst
@@ -0,0 +1,682 @@
+
+.. _profile:
+
+********************
+The Python Profilers
+********************
+
+.. sectionauthor:: James Roskind
+
+
+.. index:: single: InfoSeek Corporation
+
+Copyright © 1994, by InfoSeek Corporation, all rights reserved.
+
+Written by James Roskind. [#]_
+
+Permission to use, copy, modify, and distribute this Python software and its
+associated documentation for any purpose (subject to the restriction in the
+following sentence) without fee is hereby granted, provided that the above
+copyright notice appears in all copies, and that both that copyright notice and
+this permission notice appear in supporting documentation, and that the name of
+InfoSeek not be used in advertising or publicity pertaining to distribution of
+the software without specific, written prior permission. This permission is
+explicitly restricted to the copying and modification of the software to remain
+in Python, compiled Python, or other languages (such as C) wherein the modified
+or derived code is exclusively imported into a Python module.
+
+INFOSEEK CORPORATION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT
+SHALL INFOSEEK CORPORATION BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
+DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+The profiler was written after only programming in Python for 3 weeks. As a
+result, it is probably clumsy code, but I don't know for sure yet 'cause I'm a
+beginner :-). I did work hard to make the code run fast, so that profiling
+would be a reasonable thing to do. I tried not to repeat code fragments, but
+I'm sure I did some stuff in really awkward ways at times. Please send
+suggestions for improvements to: jar@netscape.com. I won't promise *any*
+support. ...but I'd appreciate the feedback.
+
+
+.. _profiler-introduction:
+
+Introduction to the profilers
+=============================
+
+.. index::
+ single: deterministic profiling
+ single: profiling, deterministic
+
+A :dfn:`profiler` is a program that describes the run time performance of a
+program, providing a variety of statistics. This documentation describes the
+profiler functionality provided in the modules :mod:`profile` and :mod:`pstats`.
+This profiler provides :dfn:`deterministic profiling` of any Python programs.
+It also provides a series of report generation tools to allow users to rapidly
+examine the results of a profile operation.
+
+The Python standard library provides three different profilers:
+
+#. :mod:`profile`, a pure Python module, described in the sequel. Copyright ©
+ 1994, by InfoSeek Corporation.
+
+ .. versionchanged:: 2.4
+ also reports the time spent in calls to built-in functions and methods.
+
+#. :mod:`cProfile`, a module written in C, with a reasonable overhead that makes
+ it suitable for profiling long-running programs. Based on :mod:`lsprof`,
+ contributed by Brett Rosen and Ted Czotter.
+
+ .. versionadded:: 2.5
+
+#. :mod:`hotshot`, a C module focusing on minimizing the overhead while
+ profiling, at the expense of long data post-processing times.
+
+ .. versionchanged:: 2.5
+ the results should be more meaningful than in the past: the timing core
+ contained a critical bug.
+
+The :mod:`profile` and :mod:`cProfile` modules export the same interface, so
+they are mostly interchangeables; :mod:`cProfile` has a much lower overhead but
+is not so far as well-tested and might not be available on all systems.
+:mod:`cProfile` is really a compatibility layer on top of the internal
+:mod:`_lsprof` module. The :mod:`hotshot` module is reserved to specialized
+usages.
+
+.. % \section{How Is This Profiler Different From The Old Profiler?}
+.. % \nodename{Profiler Changes}
+.. %
+.. % (This section is of historical importance only; the old profiler
+.. % discussed here was last seen in Python 1.1.)
+.. %
+.. % The big changes from old profiling module are that you get more
+.. % information, and you pay less CPU time. It's not a trade-off, it's a
+.. % trade-up.
+.. %
+.. % To be specific:
+.. %
+.. % \begin{description}
+.. %
+.. % \item[Bugs removed:]
+.. % Local stack frame is no longer molested, execution time is now charged
+.. % to correct functions.
+.. %
+.. % \item[Accuracy increased:]
+.. % Profiler execution time is no longer charged to user's code,
+.. % calibration for platform is supported, file reads are not done \emph{by}
+.. % profiler \emph{during} profiling (and charged to user's code!).
+.. %
+.. % \item[Speed increased:]
+.. % Overhead CPU cost was reduced by more than a factor of two (perhaps a
+.. % factor of five), lightweight profiler module is all that must be
+.. % loaded, and the report generating module (\module{pstats}) is not needed
+.. % during profiling.
+.. %
+.. % \item[Recursive functions support:]
+.. % Cumulative times in recursive functions are correctly calculated;
+.. % recursive entries are counted.
+.. %
+.. % \item[Large growth in report generating UI:]
+.. % Distinct profiles runs can be added together forming a comprehensive
+.. % report; functions that import statistics take arbitrary lists of
+.. % files; sorting criteria is now based on keywords (instead of 4 integer
+.. % options); reports shows what functions were profiled as well as what
+.. % profile file was referenced; output format has been improved.
+.. %
+.. % \end{description}
+
+
+.. _profile-instant:
+
+Instant User's Manual
+=====================
+
+This section is provided for users that "don't want to read the manual." It
+provides a very brief overview, and allows a user to rapidly perform profiling
+on an existing application.
+
+To profile an application with a main entry point of :func:`foo`, you would add
+the following to your module::
+
+ import cProfile
+ cProfile.run('foo()')
+
+(Use :mod:`profile` instead of :mod:`cProfile` if the latter is not available on
+your system.)
+
+The above action would cause :func:`foo` to be run, and a series of informative
+lines (the profile) to be printed. The above approach is most useful when
+working with the interpreter. If you would like to save the results of a
+profile into a file for later examination, you can supply a file name as the
+second argument to the :func:`run` function::
+
+ import cProfile
+ cProfile.run('foo()', 'fooprof')
+
+The file :file:`cProfile.py` can also be invoked as a script to profile another
+script. For example::
+
+ python -m cProfile myscript.py
+
+:file:`cProfile.py` accepts two optional arguments on the command line::
+
+ cProfile.py [-o output_file] [-s sort_order]
+
+:option:`-s` only applies to standard output (:option:`-o` is not supplied).
+Look in the :class:`Stats` documentation for valid sort values.
+
+When you wish to review the profile, you should use the methods in the
+:mod:`pstats` module. Typically you would load the statistics data as follows::
+
+ import pstats
+ p = pstats.Stats('fooprof')
+
+The class :class:`Stats` (the above code just created an instance of this class)
+has a variety of methods for manipulating and printing the data that was just
+read into ``p``. When you ran :func:`cProfile.run` above, what was printed was
+the result of three method calls::
+
+ p.strip_dirs().sort_stats(-1).print_stats()
+
+The first method removed the extraneous path from all the module names. The
+second method sorted all the entries according to the standard module/line/name
+string that is printed. The third method printed out all the statistics. You
+might try the following sort calls:
+
+.. % (this is to comply with the semantics of the old profiler).
+
+::
+
+ p.sort_stats('name')
+ p.print_stats()
+
+The first call will actually sort the list by function name, and the second call
+will print out the statistics. The following are some interesting calls to
+experiment with::
+
+ p.sort_stats('cumulative').print_stats(10)
+
+This sorts the profile by cumulative time in a function, and then only prints
+the ten most significant lines. If you want to understand what algorithms are
+taking time, the above line is what you would use.
+
+If you were looking to see what functions were looping a lot, and taking a lot
+of time, you would do::
+
+ p.sort_stats('time').print_stats(10)
+
+to sort according to time spent within each function, and then print the
+statistics for the top ten functions.
+
+You might also try::
+
+ p.sort_stats('file').print_stats('__init__')
+
+This will sort all the statistics by file name, and then print out statistics
+for only the class init methods (since they are spelled with ``__init__`` in
+them). As one final example, you could try::
+
+ p.sort_stats('time', 'cum').print_stats(.5, 'init')
+
+This line sorts statistics with a primary key of time, and a secondary key of
+cumulative time, and then prints out some of the statistics. To be specific, the
+list is first culled down to 50% (re: ``.5``) of its original size, then only
+lines containing ``init`` are maintained, and that sub-sub-list is printed.
+
+If you wondered what functions called the above functions, you could now (``p``
+is still sorted according to the last criteria) do::
+
+ p.print_callers(.5, 'init')
+
+and you would get a list of callers for each of the listed functions.
+
+If you want more functionality, you're going to have to read the manual, or
+guess what the following functions do::
+
+ p.print_callees()
+ p.add('fooprof')
+
+Invoked as a script, the :mod:`pstats` module is a statistics browser for
+reading and examining profile dumps. It has a simple line-oriented interface
+(implemented using :mod:`cmd`) and interactive help.
+
+
+.. _deterministic-profiling:
+
+What Is Deterministic Profiling?
+================================
+
+:dfn:`Deterministic profiling` is meant to reflect the fact that all *function
+call*, *function return*, and *exception* events are monitored, and precise
+timings are made for the intervals between these events (during which time the
+user's code is executing). In contrast, :dfn:`statistical profiling` (which is
+not done by this module) randomly samples the effective instruction pointer, and
+deduces where time is being spent. The latter technique traditionally involves
+less overhead (as the code does not need to be instrumented), but provides only
+relative indications of where time is being spent.
+
+In Python, since there is an interpreter active during execution, the presence
+of instrumented code is not required to do deterministic profiling. Python
+automatically provides a :dfn:`hook` (optional callback) for each event. In
+addition, the interpreted nature of Python tends to add so much overhead to
+execution, that deterministic profiling tends to only add small processing
+overhead in typical applications. The result is that deterministic profiling is
+not that expensive, yet provides extensive run time statistics about the
+execution of a Python program.
+
+Call count statistics can be used to identify bugs in code (surprising counts),
+and to identify possible inline-expansion points (high call counts). Internal
+time statistics can be used to identify "hot loops" that should be carefully
+optimized. Cumulative time statistics should be used to identify high level
+errors in the selection of algorithms. Note that the unusual handling of
+cumulative times in this profiler allows statistics for recursive
+implementations of algorithms to be directly compared to iterative
+implementations.
+
+
+Reference Manual -- :mod:`profile` and :mod:`cProfile`
+======================================================
+
+.. module:: cProfile
+ :synopsis: Python profiler
+
+
+The primary entry point for the profiler is the global function
+:func:`profile.run` (resp. :func:`cProfile.run`). It is typically used to create
+any profile information. The reports are formatted and printed using methods of
+the class :class:`pstats.Stats`. The following is a description of all of these
+standard entry points and functions. For a more in-depth view of some of the
+code, consider reading the later section on Profiler Extensions, which includes
+discussion of how to derive "better" profilers from the classes presented, or
+reading the source code for these modules.
+
+
+.. function:: run(command[, filename])
+
+ This function takes a single argument that can be passed to the :func:`exec`
+ function, and an optional file name. In all cases this routine attempts to
+ :func:`exec` its first argument, and gather profiling statistics from the
+ execution. If no file name is present, then this function automatically
+ prints a simple profiling report, sorted by the standard name string
+ (file/line/function-name) that is presented in each line. The following is a
+ typical output from such a call::
+
+ 2706 function calls (2004 primitive calls) in 4.504 CPU seconds
+
+ Ordered by: standard name
+
+ ncalls tottime percall cumtime percall filename:lineno(function)
+ 2 0.006 0.003 0.953 0.477 pobject.py:75(save_objects)
+ 43/3 0.533 0.012 0.749 0.250 pobject.py:99(evaluate)
+ ...
+
+ The first line indicates that 2706 calls were monitored. Of those calls, 2004
+ were :dfn:`primitive`. We define :dfn:`primitive` to mean that the call was not
+ induced via recursion. The next line: ``Ordered by: standard name``, indicates
+ that the text string in the far right column was used to sort the output. The
+ column headings include:
+
+ ncalls
+ for the number of calls,
+
+ tottime
+ for the total time spent in the given function (and excluding time made in calls
+ to sub-functions),
+
+ percall
+ is the quotient of ``tottime`` divided by ``ncalls``
+
+ cumtime
+ is the total time spent in this and all subfunctions (from invocation till
+ exit). This figure is accurate *even* for recursive functions.
+
+ percall
+ is the quotient of ``cumtime`` divided by primitive calls
+
+ filename:lineno(function)
+ provides the respective data of each function
+
+ When there are two numbers in the first column (for example, ``43/3``), then the
+ latter is the number of primitive calls, and the former is the actual number of
+ calls. Note that when the function does not recurse, these two values are the
+ same, and only the single figure is printed.
+
+
+.. function:: runctx(command, globals, locals[, filename])
+
+ This function is similar to :func:`run`, with added arguments to supply the
+ globals and locals dictionaries for the *command* string.
+
+Analysis of the profiler data is done using the :class:`Stats` class.
+
+.. note::
+
+ The :class:`Stats` class is defined in the :mod:`pstats` module.
+
+
+.. module:: pstats
+ :synopsis: Statistics object for use with the profiler.
+
+
+.. class:: Stats(filename[, stream=sys.stdout[, ...]])
+
+ This class constructor creates an instance of a "statistics object" from a
+ *filename* (or set of filenames). :class:`Stats` objects are manipulated by
+ methods, in order to print useful reports. You may specify an alternate output
+ stream by giving the keyword argument, ``stream``.
+
+ The file selected by the above constructor must have been created by the
+ corresponding version of :mod:`profile` or :mod:`cProfile`. To be specific,
+ there is *no* file compatibility guaranteed with future versions of this
+ profiler, and there is no compatibility with files produced by other profilers.
+ If several files are provided, all the statistics for identical functions will
+ be coalesced, so that an overall view of several processes can be considered in
+ a single report. If additional files need to be combined with data in an
+ existing :class:`Stats` object, the :meth:`add` method can be used.
+
+ .. % (such as the old system profiler).
+
+ .. versionchanged:: 2.5
+ The *stream* parameter was added.
+
+
+.. _profile-stats:
+
+The :class:`Stats` Class
+------------------------
+
+:class:`Stats` objects have the following methods:
+
+
+.. method:: Stats.strip_dirs()
+
+ This method for the :class:`Stats` class removes all leading path information
+ from file names. It is very useful in reducing the size of the printout to fit
+ within (close to) 80 columns. This method modifies the object, and the stripped
+ information is lost. After performing a strip operation, the object is
+ considered to have its entries in a "random" order, as it was just after object
+ initialization and loading. If :meth:`strip_dirs` causes two function names to
+ be indistinguishable (they are on the same line of the same filename, and have
+ the same function name), then the statistics for these two entries are
+ accumulated into a single entry.
+
+
+.. method:: Stats.add(filename[, ...])
+
+ This method of the :class:`Stats` class accumulates additional profiling
+ information into the current profiling object. Its arguments should refer to
+ filenames created by the corresponding version of :func:`profile.run` or
+ :func:`cProfile.run`. Statistics for identically named (re: file, line, name)
+ functions are automatically accumulated into single function statistics.
+
+
+.. method:: Stats.dump_stats(filename)
+
+ Save the data loaded into the :class:`Stats` object to a file named *filename*.
+ The file is created if it does not exist, and is overwritten if it already
+ exists. This is equivalent to the method of the same name on the
+ :class:`profile.Profile` and :class:`cProfile.Profile` classes.
+
+ .. versionadded:: 2.3
+
+
+.. method:: Stats.sort_stats(key[, ...])
+
+ This method modifies the :class:`Stats` object by sorting it according to the
+ supplied criteria. The argument is typically a string identifying the basis of
+ a sort (example: ``'time'`` or ``'name'``).
+
+ When more than one key is provided, then additional keys are used as secondary
+ criteria when there is equality in all keys selected before them. For example,
+ ``sort_stats('name', 'file')`` will sort all the entries according to their
+ function name, and resolve all ties (identical function names) by sorting by
+ file name.
+
+ Abbreviations can be used for any key names, as long as the abbreviation is
+ unambiguous. The following are the keys currently defined:
+
+ +------------------+----------------------+
+ | Valid Arg | Meaning |
+ +==================+======================+
+ | ``'calls'`` | call count |
+ +------------------+----------------------+
+ | ``'cumulative'`` | cumulative time |
+ +------------------+----------------------+
+ | ``'file'`` | file name |
+ +------------------+----------------------+
+ | ``'module'`` | file name |
+ +------------------+----------------------+
+ | ``'pcalls'`` | primitive call count |
+ +------------------+----------------------+
+ | ``'line'`` | line number |
+ +------------------+----------------------+
+ | ``'name'`` | function name |
+ +------------------+----------------------+
+ | ``'nfl'`` | name/file/line |
+ +------------------+----------------------+
+ | ``'stdname'`` | standard name |
+ +------------------+----------------------+
+ | ``'time'`` | internal time |
+ +------------------+----------------------+
+
+ Note that all sorts on statistics are in descending order (placing most time
+ consuming items first), where as name, file, and line number searches are in
+ ascending order (alphabetical). The subtle distinction between ``'nfl'`` and
+ ``'stdname'`` is that the standard name is a sort of the name as printed, which
+ means that the embedded line numbers get compared in an odd way. For example,
+ lines 3, 20, and 40 would (if the file names were the same) appear in the string
+ order 20, 3 and 40. In contrast, ``'nfl'`` does a numeric compare of the line
+ numbers. In fact, ``sort_stats('nfl')`` is the same as ``sort_stats('name',
+ 'file', 'line')``.
+
+ For backward-compatibility reasons, the numeric arguments ``-1``, ``0``, ``1``,
+ and ``2`` are permitted. They are interpreted as ``'stdname'``, ``'calls'``,
+ ``'time'``, and ``'cumulative'`` respectively. If this old style format
+ (numeric) is used, only one sort key (the numeric key) will be used, and
+ additional arguments will be silently ignored.
+
+ .. % For compatibility with the old profiler,
+
+
+.. method:: Stats.reverse_order()
+
+ This method for the :class:`Stats` class reverses the ordering of the basic list
+ within the object. Note that by default ascending vs descending order is
+ properly selected based on the sort key of choice.
+
+ .. % This method is provided primarily for
+ .. % compatibility with the old profiler.
+
+
+.. method:: Stats.print_stats([restriction, ...])
+
+ This method for the :class:`Stats` class prints out a report as described in the
+ :func:`profile.run` definition.
+
+ The order of the printing is based on the last :meth:`sort_stats` operation done
+ on the object (subject to caveats in :meth:`add` and :meth:`strip_dirs`).
+
+ The arguments provided (if any) can be used to limit the list down to the
+ significant entries. Initially, the list is taken to be the complete set of
+ profiled functions. Each restriction is either an integer (to select a count of
+ lines), or a decimal fraction between 0.0 and 1.0 inclusive (to select a
+ percentage of lines), or a regular expression (to pattern match the standard
+ name that is printed; as of Python 1.5b1, this uses the Perl-style regular
+ expression syntax defined by the :mod:`re` module). If several restrictions are
+ provided, then they are applied sequentially. For example::
+
+ print_stats(.1, 'foo:')
+
+ would first limit the printing to first 10% of list, and then only print
+ functions that were part of filename :file:`.\*foo:`. In contrast, the
+ command::
+
+ print_stats('foo:', .1)
+
+ would limit the list to all functions having file names :file:`.\*foo:`, and
+ then proceed to only print the first 10% of them.
+
+
+.. method:: Stats.print_callers([restriction, ...])
+
+ This method for the :class:`Stats` class prints a list of all functions that
+ called each function in the profiled database. The ordering is identical to
+ that provided by :meth:`print_stats`, and the definition of the restricting
+ argument is also identical. Each caller is reported on its own line. The
+ format differs slightly depending on the profiler that produced the stats:
+
+ * With :mod:`profile`, a number is shown in parentheses after each caller to
+ show how many times this specific call was made. For convenience, a second
+ non-parenthesized number repeats the cumulative time spent in the function
+ at the right.
+
+ * With :mod:`cProfile`, each caller is preceeded by three numbers: the number of
+ times this specific call was made, and the total and cumulative times spent in
+ the current function while it was invoked by this specific caller.
+
+
+.. method:: Stats.print_callees([restriction, ...])
+
+ This method for the :class:`Stats` class prints a list of all function that were
+ called by the indicated function. Aside from this reversal of direction of
+ calls (re: called vs was called by), the arguments and ordering are identical to
+ the :meth:`print_callers` method.
+
+
+.. _profile-limits:
+
+Limitations
+===========
+
+One limitation has to do with accuracy of timing information. There is a
+fundamental problem with deterministic profilers involving accuracy. The most
+obvious restriction is that the underlying "clock" is only ticking at a rate
+(typically) of about .001 seconds. Hence no measurements will be more accurate
+than the underlying clock. If enough measurements are taken, then the "error"
+will tend to average out. Unfortunately, removing this first error induces a
+second source of error.
+
+The second problem is that it "takes a while" from when an event is dispatched
+until the profiler's call to get the time actually *gets* the state of the
+clock. Similarly, there is a certain lag when exiting the profiler event
+handler from the time that the clock's value was obtained (and then squirreled
+away), until the user's code is once again executing. As a result, functions
+that are called many times, or call many functions, will typically accumulate
+this error. The error that accumulates in this fashion is typically less than
+the accuracy of the clock (less than one clock tick), but it *can* accumulate
+and become very significant.
+
+The problem is more important with :mod:`profile` than with the lower-overhead
+:mod:`cProfile`. For this reason, :mod:`profile` provides a means of
+calibrating itself for a given platform so that this error can be
+probabilistically (on the average) removed. After the profiler is calibrated, it
+will be more accurate (in a least square sense), but it will sometimes produce
+negative numbers (when call counts are exceptionally low, and the gods of
+probability work against you :-). ) Do *not* be alarmed by negative numbers in
+the profile. They should *only* appear if you have calibrated your profiler,
+and the results are actually better than without calibration.
+
+
+.. _profile-calibration:
+
+Calibration
+===========
+
+The profiler of the :mod:`profile` module subtracts a constant from each event
+handling time to compensate for the overhead of calling the time function, and
+socking away the results. By default, the constant is 0. The following
+procedure can be used to obtain a better constant for a given platform (see
+discussion in section Limitations above). ::
+
+ import profile
+ pr = profile.Profile()
+ for i in range(5):
+ print pr.calibrate(10000)
+
+The method executes the number of Python calls given by the argument, directly
+and again under the profiler, measuring the time for both. It then computes the
+hidden overhead per profiler event, and returns that as a float. For example,
+on an 800 MHz Pentium running Windows 2000, and using Python's time.clock() as
+the timer, the magical number is about 12.5e-6.
+
+The object of this exercise is to get a fairly consistent result. If your
+computer is *very* fast, or your timer function has poor resolution, you might
+have to pass 100000, or even 1000000, to get consistent results.
+
+When you have a consistent answer, there are three ways you can use it: [#]_ ::
+
+ import profile
+
+ # 1. Apply computed bias to all Profile instances created hereafter.
+ profile.Profile.bias = your_computed_bias
+
+ # 2. Apply computed bias to a specific Profile instance.
+ pr = profile.Profile()
+ pr.bias = your_computed_bias
+
+ # 3. Specify computed bias in instance constructor.
+ pr = profile.Profile(bias=your_computed_bias)
+
+If you have a choice, you are better off choosing a smaller constant, and then
+your results will "less often" show up as negative in profile statistics.
+
+
+.. _profiler-extensions:
+
+Extensions --- Deriving Better Profilers
+========================================
+
+The :class:`Profile` class of both modules, :mod:`profile` and :mod:`cProfile`,
+were written so that derived classes could be developed to extend the profiler.
+The details are not described here, as doing this successfully requires an
+expert understanding of how the :class:`Profile` class works internally. Study
+the source code of the module carefully if you want to pursue this.
+
+If all you want to do is change how current time is determined (for example, to
+force use of wall-clock time or elapsed process time), pass the timing function
+you want to the :class:`Profile` class constructor::
+
+ pr = profile.Profile(your_time_func)
+
+The resulting profiler will then call :func:`your_time_func`.
+
+:class:`profile.Profile`
+ :func:`your_time_func` should return a single number, or a list of numbers whose
+ sum is the current time (like what :func:`os.times` returns). If the function
+ returns a single time number, or the list of returned numbers has length 2, then
+ you will get an especially fast version of the dispatch routine.
+
+ Be warned that you should calibrate the profiler class for the timer function
+ that you choose. For most machines, a timer that returns a lone integer value
+ will provide the best results in terms of low overhead during profiling.
+ (:func:`os.times` is *pretty* bad, as it returns a tuple of floating point
+ values). If you want to substitute a better timer in the cleanest fashion,
+ derive a class and hardwire a replacement dispatch method that best handles your
+ timer call, along with the appropriate calibration constant.
+
+:class:`cProfile.Profile`
+ :func:`your_time_func` should return a single number. If it returns plain
+ integers, you can also invoke the class constructor with a second argument
+ specifying the real duration of one unit of time. For example, if
+ :func:`your_integer_time_func` returns times measured in thousands of seconds,
+ you would constuct the :class:`Profile` instance as follows::
+
+ pr = profile.Profile(your_integer_time_func, 0.001)
+
+ As the :mod:`cProfile.Profile` class cannot be calibrated, custom timer
+ functions should be used with care and should be as fast as possible. For the
+ best results with a custom timer, it might be necessary to hard-code it in the C
+ source of the internal :mod:`_lsprof` module.
+
+.. rubric:: Footnotes
+
+.. [#] Updated and converted to LaTeX by Guido van Rossum. Further updated by Armin
+ Rigo to integrate the documentation for the new :mod:`cProfile` module of Python
+ 2.5.
+
+.. [#] Prior to Python 2.2, it was necessary to edit the profiler source code to embed
+ the bias as a literal number. You still can, but that method is no longer
+ described, because no longer needed.
+
diff --git a/Doc/library/pty.rst b/Doc/library/pty.rst
new file mode 100644
index 0000000000..5e1da225dc
--- /dev/null
+++ b/Doc/library/pty.rst
@@ -0,0 +1,48 @@
+
+:mod:`pty` --- Pseudo-terminal utilities
+========================================
+
+.. module:: pty
+ :platform: IRIX, Linux
+ :synopsis: Pseudo-Terminal Handling for SGI and Linux.
+.. moduleauthor:: Steen Lumholt
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`pty` module defines operations for handling the pseudo-terminal
+concept: starting another process and being able to write to and read from its
+controlling terminal programmatically.
+
+Because pseudo-terminal handling is highly platform dependant, there is code to
+do it only for SGI and Linux. (The Linux code is supposed to work on other
+platforms, but hasn't been tested yet.)
+
+The :mod:`pty` module defines the following functions:
+
+
+.. function:: fork()
+
+ Fork. Connect the child's controlling terminal to a pseudo-terminal. Return
+ value is ``(pid, fd)``. Note that the child gets *pid* 0, and the *fd* is
+ *invalid*. The parent's return value is the *pid* of the child, and *fd* is a
+ file descriptor connected to the child's controlling terminal (and also to the
+ child's standard input and output).
+
+
+.. function:: openpty()
+
+ Open a new pseudo-terminal pair, using :func:`os.openpty` if possible, or
+ emulation code for SGI and generic Unix systems. Return a pair of file
+ descriptors ``(master, slave)``, for the master and the slave end, respectively.
+
+
+.. function:: spawn(argv[, master_read[, stdin_read]])
+
+ Spawn a process, and connect its controlling terminal with the current
+ process's standard io. This is often used to baffle programs which insist on
+ reading from the controlling terminal.
+
+ The functions *master_read* and *stdin_read* should be functions which read from
+ a file-descriptor. The defaults try to read 1024 bytes each time they are
+ called.
+
diff --git a/Doc/library/pwd.rst b/Doc/library/pwd.rst
new file mode 100644
index 0000000000..562afd920f
--- /dev/null
+++ b/Doc/library/pwd.rst
@@ -0,0 +1,76 @@
+
+:mod:`pwd` --- The password database
+====================================
+
+.. module:: pwd
+ :platform: Unix
+ :synopsis: The password database (getpwnam() and friends).
+
+
+This module provides access to the Unix user account and password database. It
+is available on all Unix versions.
+
+Password database entries are reported as a tuple-like object, whose attributes
+correspond to the members of the ``passwd`` structure (Attribute field below,
+see ``<pwd.h>``):
+
++-------+---------------+-----------------------------+
+| Index | Attribute | Meaning |
++=======+===============+=============================+
+| 0 | ``pw_name`` | Login name |
++-------+---------------+-----------------------------+
+| 1 | ``pw_passwd`` | Optional encrypted password |
++-------+---------------+-----------------------------+
+| 2 | ``pw_uid`` | Numerical user ID |
++-------+---------------+-----------------------------+
+| 3 | ``pw_gid`` | Numerical group ID |
++-------+---------------+-----------------------------+
+| 4 | ``pw_gecos`` | User name or comment field |
++-------+---------------+-----------------------------+
+| 5 | ``pw_dir`` | User home directory |
++-------+---------------+-----------------------------+
+| 6 | ``pw_shell`` | User command interpreter |
++-------+---------------+-----------------------------+
+
+The uid and gid items are integers, all others are strings. :exc:`KeyError` is
+raised if the entry asked for cannot be found.
+
+.. note::
+
+ .. index:: module: crypt
+
+ In traditional Unix the field ``pw_passwd`` usually contains a password
+ encrypted with a DES derived algorithm (see module :mod:`crypt`). However most
+ modern unices use a so-called *shadow password* system. On those unices the
+ *pw_passwd* field only contains an asterisk (``'*'``) or the letter ``'x'``
+ where the encrypted password is stored in a file :file:`/etc/shadow` which is
+ not world readable. Whether the *pw_passwd* field contains anything useful is
+ system-dependent. If available, the :mod:`spwd` module should be used where
+ access to the encrypted password is required.
+
+It defines the following items:
+
+
+.. function:: getpwuid(uid)
+
+ Return the password database entry for the given numeric user ID.
+
+
+.. function:: getpwnam(name)
+
+ Return the password database entry for the given user name.
+
+
+.. function:: getpwall()
+
+ Return a list of all available password database entries, in arbitrary order.
+
+
+.. seealso::
+
+ Module :mod:`grp`
+ An interface to the group database, similar to this.
+
+ Module :mod:`spwd`
+ An interface to the shadow password database, similar to this.
+
diff --git a/Doc/library/py_compile.rst b/Doc/library/py_compile.rst
new file mode 100644
index 0000000000..c81584660f
--- /dev/null
+++ b/Doc/library/py_compile.rst
@@ -0,0 +1,55 @@
+:mod:`py_compile` --- Compile Python source files
+=================================================
+
+.. module:: py_compile
+ :synopsis: Generate byte-code files from Python source files.
+
+.. % Documentation based on module docstrings, by Fred L. Drake, Jr.
+.. % <fdrake@acm.org>
+
+
+
+.. index:: pair: file; byte-code
+
+The :mod:`py_compile` module provides a function to generate a byte-code file
+from a source file, and another function used when the module source file is
+invoked as a script.
+
+Though not often needed, this function can be useful when installing modules for
+shared use, especially if some of the users may not have permission to write the
+byte-code cache files in the directory containing the source code.
+
+
+.. exception:: PyCompileError
+
+ Exception raised when an error occurs while attempting to compile the file.
+
+
+.. function:: compile(file[, cfile[, dfile[, doraise]]])
+
+ Compile a source file to byte-code and write out the byte-code cache file. The
+ source code is loaded from the file name *file*. The byte-code is written to
+ *cfile*, which defaults to *file* ``+`` ``'c'`` (``'o'`` if optimization is
+ enabled in the current interpreter). If *dfile* is specified, it is used as the
+ name of the source file in error messages instead of *file*. If *doraise* is
+ true, a :exc:`PyCompileError` is raised when an error is encountered while
+ compiling *file*. If *doraise* is false (the default), an error string is
+ written to ``sys.stderr``, but no exception is raised.
+
+
+.. function:: main([args])
+
+ Compile several source files. The files named in *args* (or on the command
+ line, if *args* is not specified) are compiled and the resulting bytecode is
+ cached in the normal manner. This function does not search a directory
+ structure to locate source files; it only compiles files named explicitly.
+
+When this module is run as a script, the :func:`main` is used to compile all the
+files named on the command line.
+
+
+.. seealso::
+
+ Module :mod:`compileall`
+ Utilities to compile all Python source files in a directory tree.
+
diff --git a/Doc/library/pyclbr.rst b/Doc/library/pyclbr.rst
new file mode 100644
index 0000000000..5a77b4e876
--- /dev/null
+++ b/Doc/library/pyclbr.rst
@@ -0,0 +1,112 @@
+
+:mod:`pyclbr` --- Python class browser support
+==============================================
+
+.. module:: pyclbr
+ :synopsis: Supports information extraction for a Python class browser.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`pyclbr` can be used to determine some limited information about the
+classes, methods and top-level functions defined in a module. The information
+provided is sufficient to implement a traditional three-pane class browser. The
+information is extracted from the source code rather than by importing the
+module, so this module is safe to use with untrusted source code. This
+restriction makes it impossible to use this module with modules not implemented
+in Python, including many standard and optional extension modules.
+
+
+.. function:: readmodule(module[, path])
+
+ Read a module and return a dictionary mapping class names to class descriptor
+ objects. The parameter *module* should be the name of a module as a string; it
+ may be the name of a module within a package. The *path* parameter should be a
+ sequence, and is used to augment the value of ``sys.path``, which is used to
+ locate module source code.
+
+ .. % The 'inpackage' parameter appears to be for internal use only....
+
+
+.. function:: readmodule_ex(module[, path])
+
+ Like :func:`readmodule`, but the returned dictionary, in addition to mapping
+ class names to class descriptor objects, also maps top-level function names to
+ function descriptor objects. Moreover, if the module being read is a package,
+ the key ``'__path__'`` in the returned dictionary has as its value a list which
+ contains the package search path.
+
+ .. % The 'inpackage' parameter appears to be for internal use only....
+
+
+.. _pyclbr-class-objects:
+
+Class Descriptor Objects
+------------------------
+
+The class descriptor objects used as values in the dictionary returned by
+:func:`readmodule` and :func:`readmodule_ex` provide the following data members:
+
+
+.. attribute:: class_descriptor.module
+
+ The name of the module defining the class described by the class descriptor.
+
+
+.. attribute:: class_descriptor.name
+
+ The name of the class.
+
+
+.. attribute:: class_descriptor.super
+
+ A list of class descriptors which describe the immediate base classes of the
+ class being described. Classes which are named as superclasses but which are
+ not discoverable by :func:`readmodule` are listed as a string with the class
+ name instead of class descriptors.
+
+
+.. attribute:: class_descriptor.methods
+
+ A dictionary mapping method names to line numbers.
+
+
+.. attribute:: class_descriptor.file
+
+ Name of the file containing the ``class`` statement defining the class.
+
+
+.. attribute:: class_descriptor.lineno
+
+ The line number of the ``class`` statement within the file named by
+ :attr:`file`.
+
+
+.. _pyclbr-function-objects:
+
+Function Descriptor Objects
+---------------------------
+
+The function descriptor objects used as values in the dictionary returned by
+:func:`readmodule_ex` provide the following data members:
+
+
+.. attribute:: function_descriptor.module
+
+ The name of the module defining the function described by the function
+ descriptor.
+
+
+.. attribute:: function_descriptor.name
+
+ The name of the function.
+
+
+.. attribute:: function_descriptor.file
+
+ Name of the file containing the ``def`` statement defining the function.
+
+
+.. attribute:: function_descriptor.lineno
+
+ The line number of the ``def`` statement within the file named by :attr:`file`.
+
diff --git a/Doc/library/pydoc.rst b/Doc/library/pydoc.rst
new file mode 100644
index 0000000000..2df127c0af
--- /dev/null
+++ b/Doc/library/pydoc.rst
@@ -0,0 +1,65 @@
+
+:mod:`pydoc` --- Documentation generator and online help system
+===============================================================
+
+.. module:: pydoc
+ :synopsis: Documentation generator and online help system.
+.. moduleauthor:: Ka-Ping Yee <ping@lfw.org>
+.. sectionauthor:: Ka-Ping Yee <ping@lfw.org>
+
+
+.. versionadded:: 2.1
+
+.. index::
+ single: documentation; generation
+ single: documentation; online
+ single: help; online
+
+The :mod:`pydoc` module automatically generates documentation from Python
+modules. The documentation can be presented as pages of text on the console,
+served to a Web browser, or saved to HTML files.
+
+The built-in function :func:`help` invokes the online help system in the
+interactive interpreter, which uses :mod:`pydoc` to generate its documentation
+as text on the console. The same text documentation can also be viewed from
+outside the Python interpreter by running :program:`pydoc` as a script at the
+operating system's command prompt. For example, running ::
+
+ pydoc sys
+
+at a shell prompt will display documentation on the :mod:`sys` module, in a
+style similar to the manual pages shown by the Unix :program:`man` command. The
+argument to :program:`pydoc` can be the name of a function, module, or package,
+or a dotted reference to a class, method, or function within a module or module
+in a package. If the argument to :program:`pydoc` looks like a path (that is,
+it contains the path separator for your operating system, such as a slash in
+Unix), and refers to an existing Python source file, then documentation is
+produced for that file.
+
+Specifying a :option:`-w` flag before the argument will cause HTML documentation
+to be written out to a file in the current directory, instead of displaying text
+on the console.
+
+Specifying a :option:`-k` flag before the argument will search the synopsis
+lines of all available modules for the keyword given as the argument, again in a
+manner similar to the Unix :program:`man` command. The synopsis line of a
+module is the first line of its documentation string.
+
+You can also use :program:`pydoc` to start an HTTP server on the local machine
+that will serve documentation to visiting Web browsers. :program:`pydoc`
+:option:`-p 1234` will start a HTTP server on port 1234, allowing you to browse
+the documentation at ``http://localhost:1234/`` in your preferred Web browser.
+:program:`pydoc` :option:`-g` will start the server and additionally bring up a
+small :mod:`Tkinter`\ -based graphical interface to help you search for
+documentation pages.
+
+When :program:`pydoc` generates documentation, it uses the current environment
+and path to locate modules. Thus, invoking :program:`pydoc` :option:`spam`
+documents precisely the version of the module you would get if you started the
+Python interpreter and typed ``import spam``.
+
+Module docs for core modules are assumed to reside in
+http://www.python.org/doc/current/lib/. This can be overridden by setting the
+:envvar:`PYTHONDOCS` environment variable to a different URL or to a local
+directory containing the Library Reference Manual pages.
+
diff --git a/Doc/library/pyexpat.rst b/Doc/library/pyexpat.rst
new file mode 100644
index 0000000000..87ed501408
--- /dev/null
+++ b/Doc/library/pyexpat.rst
@@ -0,0 +1,873 @@
+
+:mod:`xml.parsers.expat` --- Fast XML parsing using Expat
+=========================================================
+
+.. module:: xml.parsers.expat
+ :synopsis: An interface to the Expat non-validating XML parser.
+.. moduleauthor:: Paul Prescod <paul@prescod.net>
+
+
+.. % Markup notes:
+.. %
+.. % Many of the attributes of the XMLParser objects are callbacks.
+.. % Since signature information must be presented, these are described
+.. % using the methoddesc environment. Since they are attributes which
+.. % are set by client code, in-text references to these attributes
+.. % should be marked using the \member macro and should not include the
+.. % parentheses used when marking functions and methods.
+
+.. versionadded:: 2.0
+
+.. index:: single: Expat
+
+The :mod:`xml.parsers.expat` module is a Python interface to the Expat
+non-validating XML parser. The module provides a single extension type,
+:class:`xmlparser`, that represents the current state of an XML parser. After
+an :class:`xmlparser` object has been created, various attributes of the object
+can be set to handler functions. When an XML document is then fed to the
+parser, the handler functions are called for the character data and markup in
+the XML document.
+
+.. index:: module: pyexpat
+
+This module uses the :mod:`pyexpat` module to provide access to the Expat
+parser. Direct use of the :mod:`pyexpat` module is deprecated.
+
+This module provides one exception and one type object:
+
+
+.. exception:: ExpatError
+
+ The exception raised when Expat reports an error. See section
+ :ref:`expaterror-objects` for more information on interpreting Expat errors.
+
+
+.. exception:: error
+
+ Alias for :exc:`ExpatError`.
+
+
+.. data:: XMLParserType
+
+ The type of the return values from the :func:`ParserCreate` function.
+
+The :mod:`xml.parsers.expat` module contains two functions:
+
+
+.. function:: ErrorString(errno)
+
+ Returns an explanatory string for a given error number *errno*.
+
+
+.. function:: ParserCreate([encoding[, namespace_separator]])
+
+ Creates and returns a new :class:`xmlparser` object. *encoding*, if specified,
+ must be a string naming the encoding used by the XML data. Expat doesn't
+ support as many encodings as Python does, and its repertoire of encodings can't
+ be extended; it supports UTF-8, UTF-16, ISO-8859-1 (Latin1), and ASCII. If
+ *encoding* is given it will override the implicit or explicit encoding of the
+ document.
+
+ Expat can optionally do XML namespace processing for you, enabled by providing a
+ value for *namespace_separator*. The value must be a one-character string; a
+ :exc:`ValueError` will be raised if the string has an illegal length (``None``
+ is considered the same as omission). When namespace processing is enabled,
+ element type names and attribute names that belong to a namespace will be
+ expanded. The element name passed to the element handlers
+ :attr:`StartElementHandler` and :attr:`EndElementHandler` will be the
+ concatenation of the namespace URI, the namespace separator character, and the
+ local part of the name. If the namespace separator is a zero byte (``chr(0)``)
+ then the namespace URI and the local part will be concatenated without any
+ separator.
+
+ For example, if *namespace_separator* is set to a space character (``' '``) and
+ the following document is parsed::
+
+ <?xml version="1.0"?>
+ <root xmlns = "http://default-namespace.org/"
+ xmlns:py = "http://www.python.org/ns/">
+ <py:elem1 />
+ <elem2 xmlns="" />
+ </root>
+
+ :attr:`StartElementHandler` will receive the following strings for each
+ element::
+
+ http://default-namespace.org/ root
+ http://www.python.org/ns/ elem1
+ elem2
+
+
+.. seealso::
+
+ `The Expat XML Parser <http://www.libexpat.org/>`_
+ Home page of the Expat project.
+
+
+.. _xmlparser-objects:
+
+XMLParser Objects
+-----------------
+
+:class:`xmlparser` objects have the following methods:
+
+
+.. method:: xmlparser.Parse(data[, isfinal])
+
+ Parses the contents of the string *data*, calling the appropriate handler
+ functions to process the parsed data. *isfinal* must be true on the final call
+ to this method. *data* can be the empty string at any time.
+
+
+.. method:: xmlparser.ParseFile(file)
+
+ Parse XML data reading from the object *file*. *file* only needs to provide
+ the ``read(nbytes)`` method, returning the empty string when there's no more
+ data.
+
+
+.. method:: xmlparser.SetBase(base)
+
+ Sets the base to be used for resolving relative URIs in system identifiers in
+ declarations. Resolving relative identifiers is left to the application: this
+ value will be passed through as the *base* argument to the
+ :func:`ExternalEntityRefHandler`, :func:`NotationDeclHandler`, and
+ :func:`UnparsedEntityDeclHandler` functions.
+
+
+.. method:: xmlparser.GetBase()
+
+ Returns a string containing the base set by a previous call to :meth:`SetBase`,
+ or ``None`` if :meth:`SetBase` hasn't been called.
+
+
+.. method:: xmlparser.GetInputContext()
+
+ Returns the input data that generated the current event as a string. The data is
+ in the encoding of the entity which contains the text. When called while an
+ event handler is not active, the return value is ``None``.
+
+ .. versionadded:: 2.1
+
+
+.. method:: xmlparser.ExternalEntityParserCreate(context[, encoding])
+
+ Create a "child" parser which can be used to parse an external parsed entity
+ referred to by content parsed by the parent parser. The *context* parameter
+ should be the string passed to the :meth:`ExternalEntityRefHandler` handler
+ function, described below. The child parser is created with the
+ :attr:`ordered_attributes` and :attr:`specified_attributes` set to the values of
+ this parser.
+
+
+.. method:: xmlparser.UseForeignDTD([flag])
+
+ Calling this with a true value for *flag* (the default) will cause Expat to call
+ the :attr:`ExternalEntityRefHandler` with :const:`None` for all arguments to
+ allow an alternate DTD to be loaded. If the document does not contain a
+ document type declaration, the :attr:`ExternalEntityRefHandler` will still be
+ called, but the :attr:`StartDoctypeDeclHandler` and
+ :attr:`EndDoctypeDeclHandler` will not be called.
+
+ Passing a false value for *flag* will cancel a previous call that passed a true
+ value, but otherwise has no effect.
+
+ This method can only be called before the :meth:`Parse` or :meth:`ParseFile`
+ methods are called; calling it after either of those have been called causes
+ :exc:`ExpatError` to be raised with the :attr:`code` attribute set to
+ :const:`errors.XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING`.
+
+ .. versionadded:: 2.3
+
+:class:`xmlparser` objects have the following attributes:
+
+
+.. attribute:: xmlparser.buffer_size
+
+ The size of the buffer used when :attr:`buffer_text` is true. This value cannot
+ be changed at this time.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: xmlparser.buffer_text
+
+ Setting this to true causes the :class:`xmlparser` object to buffer textual
+ content returned by Expat to avoid multiple calls to the
+ :meth:`CharacterDataHandler` callback whenever possible. This can improve
+ performance substantially since Expat normally breaks character data into chunks
+ at every line ending. This attribute is false by default, and may be changed at
+ any time.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: xmlparser.buffer_used
+
+ If :attr:`buffer_text` is enabled, the number of bytes stored in the buffer.
+ These bytes represent UTF-8 encoded text. This attribute has no meaningful
+ interpretation when :attr:`buffer_text` is false.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: xmlparser.ordered_attributes
+
+ Setting this attribute to a non-zero integer causes the attributes to be
+ reported as a list rather than a dictionary. The attributes are presented in
+ the order found in the document text. For each attribute, two list entries are
+ presented: the attribute name and the attribute value. (Older versions of this
+ module also used this format.) By default, this attribute is false; it may be
+ changed at any time.
+
+ .. versionadded:: 2.1
+
+
+.. attribute:: xmlparser.specified_attributes
+
+ If set to a non-zero integer, the parser will report only those attributes which
+ were specified in the document instance and not those which were derived from
+ attribute declarations. Applications which set this need to be especially
+ careful to use what additional information is available from the declarations as
+ needed to comply with the standards for the behavior of XML processors. By
+ default, this attribute is false; it may be changed at any time.
+
+ .. versionadded:: 2.1
+
+The following attributes contain values relating to the most recent error
+encountered by an :class:`xmlparser` object, and will only have correct values
+once a call to :meth:`Parse` or :meth:`ParseFile` has raised a
+:exc:`xml.parsers.expat.ExpatError` exception.
+
+
+.. attribute:: xmlparser.ErrorByteIndex
+
+ Byte index at which an error occurred.
+
+
+.. attribute:: xmlparser.ErrorCode
+
+ Numeric code specifying the problem. This value can be passed to the
+ :func:`ErrorString` function, or compared to one of the constants defined in the
+ ``errors`` object.
+
+
+.. attribute:: xmlparser.ErrorColumnNumber
+
+ Column number at which an error occurred.
+
+
+.. attribute:: xmlparser.ErrorLineNumber
+
+ Line number at which an error occurred.
+
+The following attributes contain values relating to the current parse location
+in an :class:`xmlparser` object. During a callback reporting a parse event they
+indicate the location of the first of the sequence of characters that generated
+the event. When called outside of a callback, the position indicated will be
+just past the last parse event (regardless of whether there was an associated
+callback).
+
+.. versionadded:: 2.4
+
+
+.. attribute:: xmlparser.CurrentByteIndex
+
+ Current byte index in the parser input.
+
+
+.. attribute:: xmlparser.CurrentColumnNumber
+
+ Current column number in the parser input.
+
+
+.. attribute:: xmlparser.CurrentLineNumber
+
+ Current line number in the parser input.
+
+Here is the list of handlers that can be set. To set a handler on an
+:class:`xmlparser` object *o*, use ``o.handlername = func``. *handlername* must
+be taken from the following list, and *func* must be a callable object accepting
+the correct number of arguments. The arguments are all strings, unless
+otherwise stated.
+
+
+.. method:: xmlparser.XmlDeclHandler(version, encoding, standalone)
+
+ Called when the XML declaration is parsed. The XML declaration is the
+ (optional) declaration of the applicable version of the XML recommendation, the
+ encoding of the document text, and an optional "standalone" declaration.
+ *version* and *encoding* will be strings, and *standalone* will be ``1`` if the
+ document is declared standalone, ``0`` if it is declared not to be standalone,
+ or ``-1`` if the standalone clause was omitted. This is only available with
+ Expat version 1.95.0 or newer.
+
+ .. versionadded:: 2.1
+
+
+.. method:: xmlparser.StartDoctypeDeclHandler(doctypeName, systemId, publicId, has_internal_subset)
+
+ Called when Expat begins parsing the document type declaration (``<!DOCTYPE
+ ...``). The *doctypeName* is provided exactly as presented. The *systemId* and
+ *publicId* parameters give the system and public identifiers if specified, or
+ ``None`` if omitted. *has_internal_subset* will be true if the document
+ contains and internal document declaration subset. This requires Expat version
+ 1.2 or newer.
+
+
+.. method:: xmlparser.EndDoctypeDeclHandler()
+
+ Called when Expat is done parsing the document type declaration. This requires
+ Expat version 1.2 or newer.
+
+
+.. method:: xmlparser.ElementDeclHandler(name, model)
+
+ Called once for each element type declaration. *name* is the name of the
+ element type, and *model* is a representation of the content model.
+
+
+.. method:: xmlparser.AttlistDeclHandler(elname, attname, type, default, required)
+
+ Called for each declared attribute for an element type. If an attribute list
+ declaration declares three attributes, this handler is called three times, once
+ for each attribute. *elname* is the name of the element to which the
+ declaration applies and *attname* is the name of the attribute declared. The
+ attribute type is a string passed as *type*; the possible values are
+ ``'CDATA'``, ``'ID'``, ``'IDREF'``, ... *default* gives the default value for
+ the attribute used when the attribute is not specified by the document instance,
+ or ``None`` if there is no default value (``#IMPLIED`` values). If the
+ attribute is required to be given in the document instance, *required* will be
+ true. This requires Expat version 1.95.0 or newer.
+
+
+.. method:: xmlparser.StartElementHandler(name, attributes)
+
+ Called for the start of every element. *name* is a string containing the
+ element name, and *attributes* is a dictionary mapping attribute names to their
+ values.
+
+
+.. method:: xmlparser.EndElementHandler(name)
+
+ Called for the end of every element.
+
+
+.. method:: xmlparser.ProcessingInstructionHandler(target, data)
+
+ Called for every processing instruction.
+
+
+.. method:: xmlparser.CharacterDataHandler(data)
+
+ Called for character data. This will be called for normal character data, CDATA
+ marked content, and ignorable whitespace. Applications which must distinguish
+ these cases can use the :attr:`StartCdataSectionHandler`,
+ :attr:`EndCdataSectionHandler`, and :attr:`ElementDeclHandler` callbacks to
+ collect the required information.
+
+
+.. method:: xmlparser.UnparsedEntityDeclHandler(entityName, base, systemId, publicId, notationName)
+
+ Called for unparsed (NDATA) entity declarations. This is only present for
+ version 1.2 of the Expat library; for more recent versions, use
+ :attr:`EntityDeclHandler` instead. (The underlying function in the Expat
+ library has been declared obsolete.)
+
+
+.. method:: xmlparser.EntityDeclHandler(entityName, is_parameter_entity, value, base, systemId, publicId, notationName)
+
+ Called for all entity declarations. For parameter and internal entities,
+ *value* will be a string giving the declared contents of the entity; this will
+ be ``None`` for external entities. The *notationName* parameter will be
+ ``None`` for parsed entities, and the name of the notation for unparsed
+ entities. *is_parameter_entity* will be true if the entity is a parameter entity
+ or false for general entities (most applications only need to be concerned with
+ general entities). This is only available starting with version 1.95.0 of the
+ Expat library.
+
+ .. versionadded:: 2.1
+
+
+.. method:: xmlparser.NotationDeclHandler(notationName, base, systemId, publicId)
+
+ Called for notation declarations. *notationName*, *base*, and *systemId*, and
+ *publicId* are strings if given. If the public identifier is omitted,
+ *publicId* will be ``None``.
+
+
+.. method:: xmlparser.StartNamespaceDeclHandler(prefix, uri)
+
+ Called when an element contains a namespace declaration. Namespace declarations
+ are processed before the :attr:`StartElementHandler` is called for the element
+ on which declarations are placed.
+
+
+.. method:: xmlparser.EndNamespaceDeclHandler(prefix)
+
+ Called when the closing tag is reached for an element that contained a
+ namespace declaration. This is called once for each namespace declaration on
+ the element in the reverse of the order for which the
+ :attr:`StartNamespaceDeclHandler` was called to indicate the start of each
+ namespace declaration's scope. Calls to this handler are made after the
+ corresponding :attr:`EndElementHandler` for the end of the element.
+
+
+.. method:: xmlparser.CommentHandler(data)
+
+ Called for comments. *data* is the text of the comment, excluding the leading
+ '``<!-``\ ``-``' and trailing '``-``\ ``->``'.
+
+
+.. method:: xmlparser.StartCdataSectionHandler()
+
+ Called at the start of a CDATA section. This and :attr:`EndCdataSectionHandler`
+ are needed to be able to identify the syntactical start and end for CDATA
+ sections.
+
+
+.. method:: xmlparser.EndCdataSectionHandler()
+
+ Called at the end of a CDATA section.
+
+
+.. method:: xmlparser.DefaultHandler(data)
+
+ Called for any characters in the XML document for which no applicable handler
+ has been specified. This means characters that are part of a construct which
+ could be reported, but for which no handler has been supplied.
+
+
+.. method:: xmlparser.DefaultHandlerExpand(data)
+
+ This is the same as the :func:`DefaultHandler`, but doesn't inhibit expansion
+ of internal entities. The entity reference will not be passed to the default
+ handler.
+
+
+.. method:: xmlparser.NotStandaloneHandler()
+
+ Called if the XML document hasn't been declared as being a standalone document.
+ This happens when there is an external subset or a reference to a parameter
+ entity, but the XML declaration does not set standalone to ``yes`` in an XML
+ declaration. If this handler returns ``0``, then the parser will throw an
+ :const:`XML_ERROR_NOT_STANDALONE` error. If this handler is not set, no
+ exception is raised by the parser for this condition.
+
+
+.. method:: xmlparser.ExternalEntityRefHandler(context, base, systemId, publicId)
+
+ Called for references to external entities. *base* is the current base, as set
+ by a previous call to :meth:`SetBase`. The public and system identifiers,
+ *systemId* and *publicId*, are strings if given; if the public identifier is not
+ given, *publicId* will be ``None``. The *context* value is opaque and should
+ only be used as described below.
+
+ For external entities to be parsed, this handler must be implemented. It is
+ responsible for creating the sub-parser using
+ ``ExternalEntityParserCreate(context)``, initializing it with the appropriate
+ callbacks, and parsing the entity. This handler should return an integer; if it
+ returns ``0``, the parser will throw an
+ :const:`XML_ERROR_EXTERNAL_ENTITY_HANDLING` error, otherwise parsing will
+ continue.
+
+ If this handler is not provided, external entities are reported by the
+ :attr:`DefaultHandler` callback, if provided.
+
+
+.. _expaterror-objects:
+
+ExpatError Exceptions
+---------------------
+
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+:exc:`ExpatError` exceptions have a number of interesting attributes:
+
+
+.. attribute:: ExpatError.code
+
+ Expat's internal error number for the specific error. This will match one of
+ the constants defined in the ``errors`` object from this module.
+
+ .. versionadded:: 2.1
+
+
+.. attribute:: ExpatError.lineno
+
+ Line number on which the error was detected. The first line is numbered ``1``.
+
+ .. versionadded:: 2.1
+
+
+.. attribute:: ExpatError.offset
+
+ Character offset into the line where the error occurred. The first column is
+ numbered ``0``.
+
+ .. versionadded:: 2.1
+
+
+.. _expat-example:
+
+Example
+-------
+
+The following program defines three handlers that just print out their
+arguments. ::
+
+ import xml.parsers.expat
+
+ # 3 handler functions
+ def start_element(name, attrs):
+ print 'Start element:', name, attrs
+ def end_element(name):
+ print 'End element:', name
+ def char_data(data):
+ print 'Character data:', repr(data)
+
+ p = xml.parsers.expat.ParserCreate()
+
+ p.StartElementHandler = start_element
+ p.EndElementHandler = end_element
+ p.CharacterDataHandler = char_data
+
+ p.Parse("""<?xml version="1.0"?>
+ <parent id="top"><child1 name="paul">Text goes here</child1>
+ <child2 name="fred">More text</child2>
+ </parent>""", 1)
+
+The output from this program is::
+
+ Start element: parent {'id': 'top'}
+ Start element: child1 {'name': 'paul'}
+ Character data: 'Text goes here'
+ End element: child1
+ Character data: '\n'
+ Start element: child2 {'name': 'fred'}
+ Character data: 'More text'
+ End element: child2
+ Character data: '\n'
+ End element: parent
+
+
+.. _expat-content-models:
+
+Content Model Descriptions
+--------------------------
+
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+Content modules are described using nested tuples. Each tuple contains four
+values: the type, the quantifier, the name, and a tuple of children. Children
+are simply additional content module descriptions.
+
+The values of the first two fields are constants defined in the ``model`` object
+of the :mod:`xml.parsers.expat` module. These constants can be collected in two
+groups: the model type group and the quantifier group.
+
+The constants in the model type group are:
+
+
+.. data:: XML_CTYPE_ANY
+ :noindex:
+
+ The element named by the model name was declared to have a content model of
+ ``ANY``.
+
+
+.. data:: XML_CTYPE_CHOICE
+ :noindex:
+
+ The named element allows a choice from a number of options; this is used for
+ content models such as ``(A | B | C)``.
+
+
+.. data:: XML_CTYPE_EMPTY
+ :noindex:
+
+ Elements which are declared to be ``EMPTY`` have this model type.
+
+
+.. data:: XML_CTYPE_MIXED
+ :noindex:
+
+
+.. data:: XML_CTYPE_NAME
+ :noindex:
+
+
+.. data:: XML_CTYPE_SEQ
+ :noindex:
+
+ Models which represent a series of models which follow one after the other are
+ indicated with this model type. This is used for models such as ``(A, B, C)``.
+
+The constants in the quantifier group are:
+
+
+.. data:: XML_CQUANT_NONE
+ :noindex:
+
+ No modifier is given, so it can appear exactly once, as for ``A``.
+
+
+.. data:: XML_CQUANT_OPT
+ :noindex:
+
+ The model is optional: it can appear once or not at all, as for ``A?``.
+
+
+.. data:: XML_CQUANT_PLUS
+ :noindex:
+
+ The model must occur one or more times (like ``A+``).
+
+
+.. data:: XML_CQUANT_REP
+ :noindex:
+
+ The model must occur zero or more times, as for ``A*``.
+
+
+.. _expat-errors:
+
+Expat error constants
+---------------------
+
+The following constants are provided in the ``errors`` object of the
+:mod:`xml.parsers.expat` module. These constants are useful in interpreting
+some of the attributes of the :exc:`ExpatError` exception objects raised when an
+error has occurred.
+
+The ``errors`` object has the following attributes:
+
+
+.. data:: XML_ERROR_ASYNC_ENTITY
+ :noindex:
+
+
+.. data:: XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF
+ :noindex:
+
+ An entity reference in an attribute value referred to an external entity instead
+ of an internal entity.
+
+
+.. data:: XML_ERROR_BAD_CHAR_REF
+ :noindex:
+
+ A character reference referred to a character which is illegal in XML (for
+ example, character ``0``, or '``&#0;``').
+
+
+.. data:: XML_ERROR_BINARY_ENTITY_REF
+ :noindex:
+
+ An entity reference referred to an entity which was declared with a notation, so
+ cannot be parsed.
+
+
+.. data:: XML_ERROR_DUPLICATE_ATTRIBUTE
+ :noindex:
+
+ An attribute was used more than once in a start tag.
+
+
+.. data:: XML_ERROR_INCORRECT_ENCODING
+ :noindex:
+
+
+.. data:: XML_ERROR_INVALID_TOKEN
+ :noindex:
+
+ Raised when an input byte could not properly be assigned to a character; for
+ example, a NUL byte (value ``0``) in a UTF-8 input stream.
+
+
+.. data:: XML_ERROR_JUNK_AFTER_DOC_ELEMENT
+ :noindex:
+
+ Something other than whitespace occurred after the document element.
+
+
+.. data:: XML_ERROR_MISPLACED_XML_PI
+ :noindex:
+
+ An XML declaration was found somewhere other than the start of the input data.
+
+
+.. data:: XML_ERROR_NO_ELEMENTS
+ :noindex:
+
+ The document contains no elements (XML requires all documents to contain exactly
+ one top-level element)..
+
+
+.. data:: XML_ERROR_NO_MEMORY
+ :noindex:
+
+ Expat was not able to allocate memory internally.
+
+
+.. data:: XML_ERROR_PARAM_ENTITY_REF
+ :noindex:
+
+ A parameter entity reference was found where it was not allowed.
+
+
+.. data:: XML_ERROR_PARTIAL_CHAR
+ :noindex:
+
+ An incomplete character was found in the input.
+
+
+.. data:: XML_ERROR_RECURSIVE_ENTITY_REF
+ :noindex:
+
+ An entity reference contained another reference to the same entity; possibly via
+ a different name, and possibly indirectly.
+
+
+.. data:: XML_ERROR_SYNTAX
+ :noindex:
+
+ Some unspecified syntax error was encountered.
+
+
+.. data:: XML_ERROR_TAG_MISMATCH
+ :noindex:
+
+ An end tag did not match the innermost open start tag.
+
+
+.. data:: XML_ERROR_UNCLOSED_TOKEN
+ :noindex:
+
+ Some token (such as a start tag) was not closed before the end of the stream or
+ the next token was encountered.
+
+
+.. data:: XML_ERROR_UNDEFINED_ENTITY
+ :noindex:
+
+ A reference was made to a entity which was not defined.
+
+
+.. data:: XML_ERROR_UNKNOWN_ENCODING
+ :noindex:
+
+ The document encoding is not supported by Expat.
+
+
+.. data:: XML_ERROR_UNCLOSED_CDATA_SECTION
+ :noindex:
+
+ A CDATA marked section was not closed.
+
+
+.. data:: XML_ERROR_EXTERNAL_ENTITY_HANDLING
+ :noindex:
+
+
+.. data:: XML_ERROR_NOT_STANDALONE
+ :noindex:
+
+ The parser determined that the document was not "standalone" though it declared
+ itself to be in the XML declaration, and the :attr:`NotStandaloneHandler` was
+ set and returned ``0``.
+
+
+.. data:: XML_ERROR_UNEXPECTED_STATE
+ :noindex:
+
+
+.. data:: XML_ERROR_ENTITY_DECLARED_IN_PE
+ :noindex:
+
+
+.. data:: XML_ERROR_FEATURE_REQUIRES_XML_DTD
+ :noindex:
+
+ An operation was requested that requires DTD support to be compiled in, but
+ Expat was configured without DTD support. This should never be reported by a
+ standard build of the :mod:`xml.parsers.expat` module.
+
+
+.. data:: XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING
+ :noindex:
+
+ A behavioral change was requested after parsing started that can only be changed
+ before parsing has started. This is (currently) only raised by
+ :meth:`UseForeignDTD`.
+
+
+.. data:: XML_ERROR_UNBOUND_PREFIX
+ :noindex:
+
+ An undeclared prefix was found when namespace processing was enabled.
+
+
+.. data:: XML_ERROR_UNDECLARING_PREFIX
+ :noindex:
+
+ The document attempted to remove the namespace declaration associated with a
+ prefix.
+
+
+.. data:: XML_ERROR_INCOMPLETE_PE
+ :noindex:
+
+ A parameter entity contained incomplete markup.
+
+
+.. data:: XML_ERROR_XML_DECL
+ :noindex:
+
+ The document contained no document element at all.
+
+
+.. data:: XML_ERROR_TEXT_DECL
+ :noindex:
+
+ There was an error parsing a text declaration in an external entity.
+
+
+.. data:: XML_ERROR_PUBLICID
+ :noindex:
+
+ Characters were found in the public id that are not allowed.
+
+
+.. data:: XML_ERROR_SUSPENDED
+ :noindex:
+
+ The requested operation was made on a suspended parser, but isn't allowed. This
+ includes attempts to provide additional input or to stop the parser.
+
+
+.. data:: XML_ERROR_NOT_SUSPENDED
+ :noindex:
+
+ An attempt to resume the parser was made when the parser had not been suspended.
+
+
+.. data:: XML_ERROR_ABORTED
+ :noindex:
+
+ This should not be reported to Python applications.
+
+
+.. data:: XML_ERROR_FINISHED
+ :noindex:
+
+ The requested operation was made on a parser which was finished parsing input,
+ but isn't allowed. This includes attempts to provide additional input or to
+ stop the parser.
+
+
+.. data:: XML_ERROR_SUSPEND_PE
+ :noindex:
+
diff --git a/Doc/library/python.rst b/Doc/library/python.rst
new file mode 100644
index 0000000000..3b58eee981
--- /dev/null
+++ b/Doc/library/python.rst
@@ -0,0 +1,27 @@
+
+.. _python:
+
+***********************
+Python Runtime Services
+***********************
+
+The modules described in this chapter provide a wide range of services related
+to the Python interpreter and its interaction with its environment. Here's an
+overview:
+
+
+.. toctree::
+
+ sys.rst
+ __builtin__.rst
+ __main__.rst
+ warnings.rst
+ contextlib.rst
+ atexit.rst
+ traceback.rst
+ __future__.rst
+ gc.rst
+ inspect.rst
+ site.rst
+ user.rst
+ fpectl.rst
diff --git a/Doc/library/queue.rst b/Doc/library/queue.rst
new file mode 100644
index 0000000000..c7b65fdd56
--- /dev/null
+++ b/Doc/library/queue.rst
@@ -0,0 +1,152 @@
+
+:mod:`Queue` --- A synchronized queue class
+===========================================
+
+.. module:: Queue
+ :synopsis: A synchronized queue class.
+
+
+The :mod:`Queue` module implements a multi-producer, multi-consumer FIFO queue.
+It is especially useful in threads programming when information must be
+exchanged safely between multiple threads. The :class:`Queue` class in this
+module implements all the required locking semantics. It depends on the
+availability of thread support in Python.
+
+The :mod:`Queue` module defines the following class and exception:
+
+
+.. class:: Queue(maxsize)
+
+ Constructor for the class. *maxsize* is an integer that sets the upperbound
+ limit on the number of items that can be placed in the queue. Insertion will
+ block once this size has been reached, until queue items are consumed. If
+ *maxsize* is less than or equal to zero, the queue size is infinite.
+
+
+.. exception:: Empty
+
+ Exception raised when non-blocking :meth:`get` (or :meth:`get_nowait`) is called
+ on a :class:`Queue` object which is empty.
+
+
+.. exception:: Full
+
+ Exception raised when non-blocking :meth:`put` (or :meth:`put_nowait`) is called
+ on a :class:`Queue` object which is full.
+
+
+.. _queueobjects:
+
+Queue Objects
+-------------
+
+Class :class:`Queue` implements queue objects and has the methods described
+below. This class can be derived from in order to implement other queue
+organizations (e.g. stack) but the inheritable interface is not described here.
+See the source code for details. The public methods are:
+
+
+.. method:: Queue.qsize()
+
+ Return the approximate size of the queue. Because of multithreading semantics,
+ this number is not reliable.
+
+
+.. method:: Queue.empty()
+
+ Return ``True`` if the queue is empty, ``False`` otherwise. Because of
+ multithreading semantics, this is not reliable.
+
+
+.. method:: Queue.full()
+
+ Return ``True`` if the queue is full, ``False`` otherwise. Because of
+ multithreading semantics, this is not reliable.
+
+
+.. method:: Queue.put(item[, block[, timeout]])
+
+ Put *item* into the queue. If optional args *block* is true and *timeout* is
+ None (the default), block if necessary until a free slot is available. If
+ *timeout* is a positive number, it blocks at most *timeout* seconds and raises
+ the :exc:`Full` exception if no free slot was available within that time.
+ Otherwise (*block* is false), put an item on the queue if a free slot is
+ immediately available, else raise the :exc:`Full` exception (*timeout* is
+ ignored in that case).
+
+ .. versionadded:: 2.3
+ The *timeout* parameter.
+
+
+.. method:: Queue.put_nowait(item)
+
+ Equivalent to ``put(item, False)``.
+
+
+.. method:: Queue.get([block[, timeout]])
+
+ Remove and return an item from the queue. If optional args *block* is true and
+ *timeout* is None (the default), block if necessary until an item is available.
+ If *timeout* is a positive number, it blocks at most *timeout* seconds and
+ raises the :exc:`Empty` exception if no item was available within that time.
+ Otherwise (*block* is false), return an item if one is immediately available,
+ else raise the :exc:`Empty` exception (*timeout* is ignored in that case).
+
+ .. versionadded:: 2.3
+ The *timeout* parameter.
+
+
+.. method:: Queue.get_nowait()
+
+ Equivalent to ``get(False)``.
+
+Two methods are offered to support tracking whether enqueued tasks have been
+fully processed by daemon consumer threads.
+
+
+.. method:: Queue.task_done()
+
+ Indicate that a formerly enqueued task is complete. Used by queue consumer
+ threads. For each :meth:`get` used to fetch a task, a subsequent call to
+ :meth:`task_done` tells the queue that the processing on the task is complete.
+
+ If a :meth:`join` is currently blocking, it will resume when all items have been
+ processed (meaning that a :meth:`task_done` call was received for every item
+ that had been :meth:`put` into the queue).
+
+ Raises a :exc:`ValueError` if called more times than there were items placed in
+ the queue.
+
+ .. versionadded:: 2.5
+
+
+.. method:: Queue.join()
+
+ Blocks until all items in the queue have been gotten and processed.
+
+ The count of unfinished tasks goes up whenever an item is added to the queue.
+ The count goes down whenever a consumer thread calls :meth:`task_done` to
+ indicate that the item was retrieved and all work on it is complete. When the
+ count of unfinished tasks drops to zero, join() unblocks.
+
+ .. versionadded:: 2.5
+
+Example of how to wait for enqueued tasks to be completed::
+
+ def worker():
+ while True:
+ item = q.get()
+ do_work(item)
+ q.task_done()
+
+ q = Queue()
+ for i in range(num_worker_threads):
+ t = Thread(target=worker)
+ t.setDaemon(True)
+ t.start()
+
+ for item in source():
+ q.put(item)
+
+ q.join() # block until all tasks are done
+
diff --git a/Doc/library/quopri.rst b/Doc/library/quopri.rst
new file mode 100644
index 0000000000..8f525efdf8
--- /dev/null
+++ b/Doc/library/quopri.rst
@@ -0,0 +1,61 @@
+
+:mod:`quopri` --- Encode and decode MIME quoted-printable data
+==============================================================
+
+.. module:: quopri
+ :synopsis: Encode and decode files using the MIME quoted-printable encoding.
+
+
+.. index::
+ pair: quoted-printable; encoding
+ single: MIME; quoted-printable encoding
+
+This module performs quoted-printable transport encoding and decoding, as
+defined in :rfc:`1521`: "MIME (Multipurpose Internet Mail Extensions) Part One:
+Mechanisms for Specifying and Describing the Format of Internet Message Bodies".
+The quoted-printable encoding is designed for data where there are relatively
+few nonprintable characters; the base64 encoding scheme available via the
+:mod:`base64` module is more compact if there are many such characters, as when
+sending a graphics file.
+
+
+.. function:: decode(input, output[,header])
+
+ Decode the contents of the *input* file and write the resulting decoded binary
+ data to the *output* file. *input* and *output* must either be file objects or
+ objects that mimic the file object interface. *input* will be read until
+ ``input.readline()`` returns an empty string. If the optional argument *header*
+ is present and true, underscore will be decoded as space. This is used to decode
+ "Q"-encoded headers as described in :rfc:`1522`: "MIME (Multipurpose Internet
+ Mail Extensions) Part Two: Message Header Extensions for Non-ASCII Text".
+
+
+.. function:: encode(input, output, quotetabs)
+
+ Encode the contents of the *input* file and write the resulting quoted-printable
+ data to the *output* file. *input* and *output* must either be file objects or
+ objects that mimic the file object interface. *input* will be read until
+ ``input.readline()`` returns an empty string. *quotetabs* is a flag which
+ controls whether to encode embedded spaces and tabs; when true it encodes such
+ embedded whitespace, and when false it leaves them unencoded. Note that spaces
+ and tabs appearing at the end of lines are always encoded, as per :rfc:`1521`.
+
+
+.. function:: decodestring(s[,header])
+
+ Like :func:`decode`, except that it accepts a source string and returns the
+ corresponding decoded string.
+
+
+.. function:: encodestring(s[, quotetabs])
+
+ Like :func:`encode`, except that it accepts a source string and returns the
+ corresponding encoded string. *quotetabs* is optional (defaulting to 0), and is
+ passed straight through to :func:`encode`.
+
+
+.. seealso::
+
+ Module :mod:`base64`
+ Encode and decode MIME base64 data
+
diff --git a/Doc/library/random.rst b/Doc/library/random.rst
new file mode 100644
index 0000000000..c5d289c697
--- /dev/null
+++ b/Doc/library/random.rst
@@ -0,0 +1,315 @@
+
+:mod:`random` --- Generate pseudo-random numbers
+================================================
+
+.. module:: random
+ :synopsis: Generate pseudo-random numbers with various common distributions.
+
+
+This module implements pseudo-random number generators for various
+distributions.
+
+For integers, uniform selection from a range. For sequences, uniform selection
+of a random element, a function to generate a random permutation of a list
+in-place, and a function for random sampling without replacement.
+
+On the real line, there are functions to compute uniform, normal (Gaussian),
+lognormal, negative exponential, gamma, and beta distributions. For generating
+distributions of angles, the von Mises distribution is available.
+
+Almost all module functions depend on the basic function :func:`random`, which
+generates a random float uniformly in the semi-open range [0.0, 1.0). Python
+uses the Mersenne Twister as the core generator. It produces 53-bit precision
+floats and has a period of 2\*\*19937-1. The underlying implementation in C is
+both fast and threadsafe. The Mersenne Twister is one of the most extensively
+tested random number generators in existence. However, being completely
+deterministic, it is not suitable for all purposes, and is completely unsuitable
+for cryptographic purposes.
+
+The functions supplied by this module are actually bound methods of a hidden
+instance of the :class:`random.Random` class. You can instantiate your own
+instances of :class:`Random` to get generators that don't share state. This is
+especially useful for multi-threaded programs, creating a different instance of
+:class:`Random` for each thread, and using the :meth:`jumpahead` method to make
+it likely that the generated sequences seen by each thread don't overlap.
+
+Class :class:`Random` can also be subclassed if you want to use a different
+basic generator of your own devising: in that case, override the :meth:`random`,
+:meth:`seed`, :meth:`getstate`, :meth:`setstate` and :meth:`jumpahead` methods.
+Optionally, a new generator can supply a :meth:`getrandombits` method --- this
+allows :meth:`randrange` to produce selections over an arbitrarily large range.
+
+.. versionadded:: 2.4
+ the :meth:`getrandombits` method.
+
+As an example of subclassing, the :mod:`random` module provides the
+:class:`WichmannHill` class that implements an alternative generator in pure
+Python. The class provides a backward compatible way to reproduce results from
+earlier versions of Python, which used the Wichmann-Hill algorithm as the core
+generator. Note that this Wichmann-Hill generator can no longer be recommended:
+its period is too short by contemporary standards, and the sequence generated is
+known to fail some stringent randomness tests. See the references below for a
+recent variant that repairs these flaws.
+
+.. versionchanged:: 2.3
+ Substituted MersenneTwister for Wichmann-Hill.
+
+Bookkeeping functions:
+
+
+.. function:: seed([x])
+
+ Initialize the basic random number generator. Optional argument *x* can be any
+ hashable object. If *x* is omitted or ``None``, current system time is used;
+ current system time is also used to initialize the generator when the module is
+ first imported. If randomness sources are provided by the operating system,
+ they are used instead of the system time (see the :func:`os.urandom` function
+ for details on availability).
+
+ .. versionchanged:: 2.4
+ formerly, operating system resources were not used.
+
+ If *x* is not ``None`` or an int or long, ``hash(x)`` is used instead. If *x* is
+ an int or long, *x* is used directly.
+
+
+.. function:: getstate()
+
+ Return an object capturing the current internal state of the generator. This
+ object can be passed to :func:`setstate` to restore the state.
+
+ .. versionadded:: 2.1
+
+
+.. function:: setstate(state)
+
+ *state* should have been obtained from a previous call to :func:`getstate`, and
+ :func:`setstate` restores the internal state of the generator to what it was at
+ the time :func:`setstate` was called.
+
+ .. versionadded:: 2.1
+
+
+.. function:: jumpahead(n)
+
+ Change the internal state to one different from and likely far away from the
+ current state. *n* is a non-negative integer which is used to scramble the
+ current state vector. This is most useful in multi-threaded programs, in
+ conjuction with multiple instances of the :class:`Random` class:
+ :meth:`setstate` or :meth:`seed` can be used to force all instances into the
+ same internal state, and then :meth:`jumpahead` can be used to force the
+ instances' states far apart.
+
+ .. versionadded:: 2.1
+
+ .. versionchanged:: 2.3
+ Instead of jumping to a specific state, *n* steps ahead, ``jumpahead(n)``
+ jumps to another state likely to be separated by many steps.
+
+
+.. function:: getrandbits(k)
+
+ Returns a python :class:`long` int with *k* random bits. This method is supplied
+ with the MersenneTwister generator and some other generators may also provide it
+ as an optional part of the API. When available, :meth:`getrandbits` enables
+ :meth:`randrange` to handle arbitrarily large ranges.
+
+ .. versionadded:: 2.4
+
+Functions for integers:
+
+
+.. function:: randrange([start,] stop[, step])
+
+ Return a randomly selected element from ``range(start, stop, step)``. This is
+ equivalent to ``choice(range(start, stop, step))``, but doesn't actually build a
+ range object.
+
+ .. versionadded:: 1.5.2
+
+
+.. function:: randint(a, b)
+
+ Return a random integer *N* such that ``a <= N <= b``.
+
+Functions for sequences:
+
+
+.. function:: choice(seq)
+
+ Return a random element from the non-empty sequence *seq*. If *seq* is empty,
+ raises :exc:`IndexError`.
+
+
+.. function:: shuffle(x[, random])
+
+ Shuffle the sequence *x* in place. The optional argument *random* is a
+ 0-argument function returning a random float in [0.0, 1.0); by default, this is
+ the function :func:`random`.
+
+ Note that for even rather small ``len(x)``, the total number of permutations of
+ *x* is larger than the period of most random number generators; this implies
+ that most permutations of a long sequence can never be generated.
+
+
+.. function:: sample(population, k)
+
+ Return a *k* length list of unique elements chosen from the population sequence.
+ Used for random sampling without replacement.
+
+ .. versionadded:: 2.3
+
+ Returns a new list containing elements from the population while leaving the
+ original population unchanged. The resulting list is in selection order so that
+ all sub-slices will also be valid random samples. This allows raffle winners
+ (the sample) to be partitioned into grand prize and second place winners (the
+ subslices).
+
+ Members of the population need not be hashable or unique. If the population
+ contains repeats, then each occurrence is a possible selection in the sample.
+
+ To choose a sample from a range of integers, use an :func:`range` object as an
+ argument. This is especially fast and space efficient for sampling from a large
+ population: ``sample(range(10000000), 60)``.
+
+The following functions generate specific real-valued distributions. Function
+parameters are named after the corresponding variables in the distribution's
+equation, as used in common mathematical practice; most of these equations can
+be found in any statistics text.
+
+
+.. function:: random()
+
+ Return the next random floating point number in the range [0.0, 1.0).
+
+
+.. function:: uniform(a, b)
+
+ Return a random floating point number *N* such that ``a <= N < b``.
+
+
+.. function:: betavariate(alpha, beta)
+
+ Beta distribution. Conditions on the parameters are ``alpha > 0`` and ``beta >
+ 0``. Returned values range between 0 and 1.
+
+
+.. function:: expovariate(lambd)
+
+ Exponential distribution. *lambd* is 1.0 divided by the desired mean. (The
+ parameter would be called "lambda", but that is a reserved word in Python.)
+ Returned values range from 0 to positive infinity.
+
+
+.. function:: gammavariate(alpha, beta)
+
+ Gamma distribution. (*Not* the gamma function!) Conditions on the parameters
+ are ``alpha > 0`` and ``beta > 0``.
+
+
+.. function:: gauss(mu, sigma)
+
+ Gaussian distribution. *mu* is the mean, and *sigma* is the standard deviation.
+ This is slightly faster than the :func:`normalvariate` function defined below.
+
+
+.. function:: lognormvariate(mu, sigma)
+
+ Log normal distribution. If you take the natural logarithm of this
+ distribution, you'll get a normal distribution with mean *mu* and standard
+ deviation *sigma*. *mu* can have any value, and *sigma* must be greater than
+ zero.
+
+
+.. function:: normalvariate(mu, sigma)
+
+ Normal distribution. *mu* is the mean, and *sigma* is the standard deviation.
+
+
+.. function:: vonmisesvariate(mu, kappa)
+
+ *mu* is the mean angle, expressed in radians between 0 and 2\*\ *pi*, and *kappa*
+ is the concentration parameter, which must be greater than or equal to zero. If
+ *kappa* is equal to zero, this distribution reduces to a uniform random angle
+ over the range 0 to 2\*\ *pi*.
+
+
+.. function:: paretovariate(alpha)
+
+ Pareto distribution. *alpha* is the shape parameter.
+
+
+.. function:: weibullvariate(alpha, beta)
+
+ Weibull distribution. *alpha* is the scale parameter and *beta* is the shape
+ parameter.
+
+
+Alternative Generators:
+
+.. class:: WichmannHill([seed])
+
+ Class that implements the Wichmann-Hill algorithm as the core generator. Has all
+ of the same methods as :class:`Random` plus the :meth:`whseed` method described
+ below. Because this class is implemented in pure Python, it is not threadsafe
+ and may require locks between calls. The period of the generator is
+ 6,953,607,871,644 which is small enough to require care that two independent
+ random sequences do not overlap.
+
+
+.. function:: whseed([x])
+
+ This is obsolete, supplied for bit-level compatibility with versions of Python
+ prior to 2.1. See :func:`seed` for details. :func:`whseed` does not guarantee
+ that distinct integer arguments yield distinct internal states, and can yield no
+ more than about 2\*\*24 distinct internal states in all.
+
+
+.. class:: SystemRandom([seed])
+
+ Class that uses the :func:`os.urandom` function for generating random numbers
+ from sources provided by the operating system. Not available on all systems.
+ Does not rely on software state and sequences are not reproducible. Accordingly,
+ the :meth:`seed` and :meth:`jumpahead` methods have no effect and are ignored.
+ The :meth:`getstate` and :meth:`setstate` methods raise
+ :exc:`NotImplementedError` if called.
+
+ .. versionadded:: 2.4
+
+Examples of basic usage::
+
+ >>> random.random() # Random float x, 0.0 <= x < 1.0
+ 0.37444887175646646
+ >>> random.uniform(1, 10) # Random float x, 1.0 <= x < 10.0
+ 1.1800146073117523
+ >>> random.randint(1, 10) # Integer from 1 to 10, endpoints included
+ 7
+ >>> random.randrange(0, 101, 2) # Even integer from 0 to 100
+ 26
+ >>> random.choice('abcdefghij') # Choose a random element
+ 'c'
+
+ >>> items = [1, 2, 3, 4, 5, 6, 7]
+ >>> random.shuffle(items)
+ >>> items
+ [7, 3, 2, 5, 6, 4, 1]
+
+ >>> random.sample([1, 2, 3, 4, 5], 3) # Choose 3 elements
+ [4, 1, 5]
+
+
+
+.. seealso::
+
+ M. Matsumoto and T. Nishimura, "Mersenne Twister: A 623-dimensionally
+ equidistributed uniform pseudorandom number generator", ACM Transactions on
+ Modeling and Computer Simulation Vol. 8, No. 1, January pp.3-30 1998.
+
+ Wichmann, B. A. & Hill, I. D., "Algorithm AS 183: An efficient and portable
+ pseudo-random number generator", Applied Statistics 31 (1982) 188-190.
+
+ http://www.npl.co.uk/ssfm/download/abstracts.html#196
+ A modern variation of the Wichmann-Hill generator that greatly increases the
+ period, and passes now-standard statistical tests that the original generator
+ failed.
+
diff --git a/Doc/library/re.rst b/Doc/library/re.rst
new file mode 100644
index 0000000000..027ff16a1c
--- /dev/null
+++ b/Doc/library/re.rst
@@ -0,0 +1,921 @@
+
+:mod:`re` --- Regular expression operations
+===========================================
+
+.. module:: re
+ :synopsis: Regular expression operations.
+.. moduleauthor:: Fredrik Lundh <fredrik@pythonware.com>
+.. sectionauthor:: Andrew M. Kuchling <amk@amk.ca>
+
+
+
+
+This module provides regular expression matching operations similar to
+those found in Perl. Both patterns and strings to be searched can be
+Unicode strings as well as 8-bit strings. The :mod:`re` module is
+always available.
+
+Regular expressions use the backslash character (``'\'``) to indicate
+special forms or to allow special characters to be used without invoking
+their special meaning. This collides with Python's usage of the same
+character for the same purpose in string literals; for example, to match
+a literal backslash, one might have to write ``'\\\\'`` as the pattern
+string, because the regular expression must be ``\\``, and each
+backslash must be expressed as ``\\`` inside a regular Python string
+literal.
+
+The solution is to use Python's raw string notation for regular expression
+patterns; backslashes are not handled in any special way in a string literal
+prefixed with ``'r'``. So ``r"\n"`` is a two-character string containing
+``'\'`` and ``'n'``, while ``"\n"`` is a one-character string containing a
+newline. Usually patterns will be expressed in Python code using this raw string
+notation.
+
+.. seealso::
+
+ Mastering Regular Expressions
+ Book on regular expressions by Jeffrey Friedl, published by O'Reilly. The
+ second edition of the book no longer covers Python at all, but the first
+ edition covered writing good regular expression patterns in great detail.
+
+
+.. _re-syntax:
+
+Regular Expression Syntax
+-------------------------
+
+A regular expression (or RE) specifies a set of strings that matches it; the
+functions in this module let you check if a particular string matches a given
+regular expression (or if a given regular expression matches a particular
+string, which comes down to the same thing).
+
+Regular expressions can be concatenated to form new regular expressions; if *A*
+and *B* are both regular expressions, then *AB* is also a regular expression.
+In general, if a string *p* matches *A* and another string *q* matches *B*, the
+string *pq* will match AB. This holds unless *A* or *B* contain low precedence
+operations; boundary conditions between *A* and *B*; or have numbered group
+references. Thus, complex expressions can easily be constructed from simpler
+primitive expressions like the ones described here. For details of the theory
+and implementation of regular expressions, consult the Friedl book referenced
+above, or almost any textbook about compiler construction.
+
+A brief explanation of the format of regular expressions follows. For further
+information and a gentler presentation, consult the Regular Expression HOWTO,
+accessible from http://www.python.org/doc/howto/.
+
+Regular expressions can contain both special and ordinary characters. Most
+ordinary characters, like ``'A'``, ``'a'``, or ``'0'``, are the simplest regular
+expressions; they simply match themselves. You can concatenate ordinary
+characters, so ``last`` matches the string ``'last'``. (In the rest of this
+section, we'll write RE's in ``this special style``, usually without quotes, and
+strings to be matched ``'in single quotes'``.)
+
+Some characters, like ``'|'`` or ``'('``, are special. Special
+characters either stand for classes of ordinary characters, or affect
+how the regular expressions around them are interpreted. Regular
+expression pattern strings may not contain null bytes, but can specify
+the null byte using the ``\number`` notation, e.g., ``'\x00'``.
+
+
+The special characters are:
+
+.. %
+
+``'.'``
+ (Dot.) In the default mode, this matches any character except a newline. If
+ the :const:`DOTALL` flag has been specified, this matches any character
+ including a newline.
+
+``'^'``
+ (Caret.) Matches the start of the string, and in :const:`MULTILINE` mode also
+ matches immediately after each newline.
+
+``'$'``
+ Matches the end of the string or just before the newline at the end of the
+ string, and in :const:`MULTILINE` mode also matches before a newline. ``foo``
+ matches both 'foo' and 'foobar', while the regular expression ``foo$`` matches
+ only 'foo'. More interestingly, searching for ``foo.$`` in ``'foo1\nfoo2\n'``
+ matches 'foo2' normally, but 'foo1' in :const:`MULTILINE` mode.
+
+``'*'``
+ Causes the resulting RE to match 0 or more repetitions of the preceding RE, as
+ many repetitions as are possible. ``ab*`` will match 'a', 'ab', or 'a' followed
+ by any number of 'b's.
+
+``'+'``
+ Causes the resulting RE to match 1 or more repetitions of the preceding RE.
+ ``ab+`` will match 'a' followed by any non-zero number of 'b's; it will not
+ match just 'a'.
+
+``'?'``
+ Causes the resulting RE to match 0 or 1 repetitions of the preceding RE.
+ ``ab?`` will match either 'a' or 'ab'.
+
+``*?``, ``+?``, ``??``
+ The ``'*'``, ``'+'``, and ``'?'`` qualifiers are all :dfn:`greedy`; they match
+ as much text as possible. Sometimes this behaviour isn't desired; if the RE
+ ``<.*>`` is matched against ``'<H1>title</H1>'``, it will match the entire
+ string, and not just ``'<H1>'``. Adding ``'?'`` after the qualifier makes it
+ perform the match in :dfn:`non-greedy` or :dfn:`minimal` fashion; as *few*
+ characters as possible will be matched. Using ``.*?`` in the previous
+ expression will match only ``'<H1>'``.
+
+``{m}``
+ Specifies that exactly *m* copies of the previous RE should be matched; fewer
+ matches cause the entire RE not to match. For example, ``a{6}`` will match
+ exactly six ``'a'`` characters, but not five.
+
+``{m,n}``
+ Causes the resulting RE to match from *m* to *n* repetitions of the preceding
+ RE, attempting to match as many repetitions as possible. For example,
+ ``a{3,5}`` will match from 3 to 5 ``'a'`` characters. Omitting *m* specifies a
+ lower bound of zero, and omitting *n* specifies an infinite upper bound. As an
+ example, ``a{4,}b`` will match ``aaaab`` or a thousand ``'a'`` characters
+ followed by a ``b``, but not ``aaab``. The comma may not be omitted or the
+ modifier would be confused with the previously described form.
+
+``{m,n}?``
+ Causes the resulting RE to match from *m* to *n* repetitions of the preceding
+ RE, attempting to match as *few* repetitions as possible. This is the
+ non-greedy version of the previous qualifier. For example, on the
+ 6-character string ``'aaaaaa'``, ``a{3,5}`` will match 5 ``'a'`` characters,
+ while ``a{3,5}?`` will only match 3 characters.
+
+``'\'``
+ Either escapes special characters (permitting you to match characters like
+ ``'*'``, ``'?'``, and so forth), or signals a special sequence; special
+ sequences are discussed below.
+
+ If you're not using a raw string to express the pattern, remember that Python
+ also uses the backslash as an escape sequence in string literals; if the escape
+ sequence isn't recognized by Python's parser, the backslash and subsequent
+ character are included in the resulting string. However, if Python would
+ recognize the resulting sequence, the backslash should be repeated twice. This
+ is complicated and hard to understand, so it's highly recommended that you use
+ raw strings for all but the simplest expressions.
+
+``[]``
+ Used to indicate a set of characters. Characters can be listed individually, or
+ a range of characters can be indicated by giving two characters and separating
+ them by a ``'-'``. Special characters are not active inside sets. For example,
+ ``[akm$]`` will match any of the characters ``'a'``, ``'k'``,
+ ``'m'``, or ``'$'``; ``[a-z]`` will match any lowercase letter, and
+ ``[a-zA-Z0-9]`` matches any letter or digit. Character classes such
+ as ``\w`` or ``\S`` (defined below) are also acceptable inside a
+ range, although the characters they match depends on whether :const:`LOCALE`
+ or :const:`UNICODE` mode is in force. If you want to include a
+ ``']'`` or a ``'-'`` inside a set, precede it with a backslash, or
+ place it as the first character. The pattern ``[]]`` will match
+ ``']'``, for example.
+
+ You can match the characters not within a range by :dfn:`complementing` the set.
+ This is indicated by including a ``'^'`` as the first character of the set;
+ ``'^'`` elsewhere will simply match the ``'^'`` character. For example,
+ ``[^5]`` will match any character except ``'5'``, and ``[^^]`` will match any
+ character except ``'^'``.
+
+``'|'``
+ ``A|B``, where A and B can be arbitrary REs, creates a regular expression that
+ will match either A or B. An arbitrary number of REs can be separated by the
+ ``'|'`` in this way. This can be used inside groups (see below) as well. As
+ the target string is scanned, REs separated by ``'|'`` are tried from left to
+ right. When one pattern completely matches, that branch is accepted. This means
+ that once ``A`` matches, ``B`` will not be tested further, even if it would
+ produce a longer overall match. In other words, the ``'|'`` operator is never
+ greedy. To match a literal ``'|'``, use ``\|``, or enclose it inside a
+ character class, as in ``[|]``.
+
+``(...)``
+ Matches whatever regular expression is inside the parentheses, and indicates the
+ start and end of a group; the contents of a group can be retrieved after a match
+ has been performed, and can be matched later in the string with the ``\number``
+ special sequence, described below. To match the literals ``'('`` or ``')'``,
+ use ``\(`` or ``\)``, or enclose them inside a character class: ``[(] [)]``.
+
+``(?...)``
+ This is an extension notation (a ``'?'`` following a ``'('`` is not meaningful
+ otherwise). The first character after the ``'?'`` determines what the meaning
+ and further syntax of the construct is. Extensions usually do not create a new
+ group; ``(?P<name>...)`` is the only exception to this rule. Following are the
+ currently supported extensions.
+
+``(?iLmsux)``
+ (One or more letters from the set ``'i'``, ``'L'``, ``'m'``, ``'s'``,
+ ``'u'``, ``'x'``.) The group matches the empty string; the letters
+ set the corresponding flags: :const:`re.I` (ignore case),
+ :const:`re.L` (locale dependent), :const:`re.M` (multi-line),
+ :const:`re.S` (dot matches all), :const:`re.U` (Unicode dependent),
+ and :const:`re.X` (verbose), for the entire regular expression. (The
+ flags are described in :ref:`contents-of-module-re`.) This
+ is useful if you wish to include the flags as part of the regular
+ expression, instead of passing a *flag* argument to the
+ :func:`compile` function.
+
+ Note that the ``(?x)`` flag changes how the expression is parsed. It should be
+ used first in the expression string, or after one or more whitespace characters.
+ If there are non-whitespace characters before the flag, the results are
+ undefined.
+
+``(?:...)``
+ A non-grouping version of regular parentheses. Matches whatever regular
+ expression is inside the parentheses, but the substring matched by the group
+ *cannot* be retrieved after performing a match or referenced later in the
+ pattern.
+
+``(?P<name>...)``
+ Similar to regular parentheses, but the substring matched by the group is
+ accessible via the symbolic group name *name*. Group names must be valid Python
+ identifiers, and each group name must be defined only once within a regular
+ expression. A symbolic group is also a numbered group, just as if the group
+ were not named. So the group named 'id' in the example below can also be
+ referenced as the numbered group 1.
+
+ For example, if the pattern is ``(?P<id>[a-zA-Z_]\w*)``, the group can be
+ referenced by its name in arguments to methods of match objects, such as
+ ``m.group('id')`` or ``m.end('id')``, and also by name in pattern text (for
+ example, ``(?P=id)``) and replacement text (such as ``\g<id>``).
+
+``(?P=name)``
+ Matches whatever text was matched by the earlier group named *name*.
+
+``(?#...)``
+ A comment; the contents of the parentheses are simply ignored.
+
+``(?=...)``
+ Matches if ``...`` matches next, but doesn't consume any of the string. This is
+ called a lookahead assertion. For example, ``Isaac (?=Asimov)`` will match
+ ``'Isaac '`` only if it's followed by ``'Asimov'``.
+
+``(?!...)``
+ Matches if ``...`` doesn't match next. This is a negative lookahead assertion.
+ For example, ``Isaac (?!Asimov)`` will match ``'Isaac '`` only if it's *not*
+ followed by ``'Asimov'``.
+
+``(?<=...)``
+ Matches if the current position in the string is preceded by a match for ``...``
+ that ends at the current position. This is called a :dfn:`positive lookbehind
+ assertion`. ``(?<=abc)def`` will find a match in ``abcdef``, since the
+ lookbehind will back up 3 characters and check if the contained pattern matches.
+ The contained pattern must only match strings of some fixed length, meaning that
+ ``abc`` or ``a|b`` are allowed, but ``a*`` and ``a{3,4}`` are not. Note that
+ patterns which start with positive lookbehind assertions will never match at the
+ beginning of the string being searched; you will most likely want to use the
+ :func:`search` function rather than the :func:`match` function::
+
+ >>> import re
+ >>> m = re.search('(?<=abc)def', 'abcdef')
+ >>> m.group(0)
+ 'def'
+
+ This example looks for a word following a hyphen::
+
+ >>> m = re.search('(?<=-)\w+', 'spam-egg')
+ >>> m.group(0)
+ 'egg'
+
+``(?<!...)``
+ Matches if the current position in the string is not preceded by a match for
+ ``...``. This is called a :dfn:`negative lookbehind assertion`. Similar to
+ positive lookbehind assertions, the contained pattern must only match strings of
+ some fixed length. Patterns which start with negative lookbehind assertions may
+ match at the beginning of the string being searched.
+
+``(?(id/name)yes-pattern|no-pattern)``
+ Will try to match with ``yes-pattern`` if the group with given *id* or *name*
+ exists, and with ``no-pattern`` if it doesn't. ``no-pattern`` is optional and
+ can be omitted. For example, ``(<)?(\w+@\w+(?:\.\w+)+)(?(1)>)`` is a poor email
+ matching pattern, which will match with ``'<user@host.com>'`` as well as
+ ``'user@host.com'``, but not with ``'<user@host.com'``.
+
+ .. versionadded:: 2.4
+
+The special sequences consist of ``'\'`` and a character from the list below.
+If the ordinary character is not on the list, then the resulting RE will match
+the second character. For example, ``\$`` matches the character ``'$'``.
+
+.. %
+
+``\number``
+ Matches the contents of the group of the same number. Groups are numbered
+ starting from 1. For example, ``(.+) \1`` matches ``'the the'`` or ``'55 55'``,
+ but not ``'the end'`` (note the space after the group). This special sequence
+ can only be used to match one of the first 99 groups. If the first digit of
+ *number* is 0, or *number* is 3 octal digits long, it will not be interpreted as
+ a group match, but as the character with octal value *number*. Inside the
+ ``'['`` and ``']'`` of a character class, all numeric escapes are treated as
+ characters.
+
+``\A``
+ Matches only at the start of the string.
+
+``\b``
+ Matches the empty string, but only at the beginning or end of a word. A word is
+ defined as a sequence of alphanumeric or underscore characters, so the end of a
+ word is indicated by whitespace or a non-alphanumeric, non-underscore character.
+ Note that ``\b`` is defined as the boundary between ``\w`` and ``\ W``, so the
+ precise set of characters deemed to be alphanumeric depends on the values of the
+ ``UNICODE`` and ``LOCALE`` flags. Inside a character range, ``\b`` represents
+ the backspace character, for compatibility with Python's string literals.
+
+``\B``
+ Matches the empty string, but only when it is *not* at the beginning or end of a
+ word. This is just the opposite of ``\b``, so is also subject to the settings
+ of ``LOCALE`` and ``UNICODE``.
+
+``\d``
+ When the :const:`UNICODE` flag is not specified, matches any decimal digit; this
+ is equivalent to the set ``[0-9]``. With :const:`UNICODE`, it will match
+ whatever is classified as a digit in the Unicode character properties database.
+
+``\D``
+ When the :const:`UNICODE` flag is not specified, matches any non-digit
+ character; this is equivalent to the set ``[^0-9]``. With :const:`UNICODE`, it
+ will match anything other than character marked as digits in the Unicode
+ character properties database.
+
+``\s``
+ When the :const:`LOCALE` and :const:`UNICODE` flags are not specified, matches
+ any whitespace character; this is equivalent to the set ``[ \t\n\r\f\v]``. With
+ :const:`LOCALE`, it will match this set plus whatever characters are defined as
+ space for the current locale. If :const:`UNICODE` is set, this will match the
+ characters ``[ \t\n\r\f\v]`` plus whatever is classified as space in the Unicode
+ character properties database.
+
+``\S``
+ When the :const:`LOCALE` and :const:`UNICODE` flags are not specified, matches
+ any non-whitespace character; this is equivalent to the set ``[^ \t\n\r\f\v]``
+ With :const:`LOCALE`, it will match any character not in this set, and not
+ defined as space in the current locale. If :const:`UNICODE` is set, this will
+ match anything other than ``[ \t\n\r\f\v]`` and characters marked as space in
+ the Unicode character properties database.
+
+``\w``
+ When the :const:`LOCALE` and :const:`UNICODE` flags are not specified, matches
+ any alphanumeric character and the underscore; this is equivalent to the set
+ ``[a-zA-Z0-9_]``. With :const:`LOCALE`, it will match the set ``[0-9_]`` plus
+ whatever characters are defined as alphanumeric for the current locale. If
+ :const:`UNICODE` is set, this will match the characters ``[0-9_]`` plus whatever
+ is classified as alphanumeric in the Unicode character properties database.
+
+``\W``
+ When the :const:`LOCALE` and :const:`UNICODE` flags are not specified, matches
+ any non-alphanumeric character; this is equivalent to the set ``[^a-zA-Z0-9_]``.
+ With :const:`LOCALE`, it will match any character not in the set ``[0-9_]``, and
+ not defined as alphanumeric for the current locale. If :const:`UNICODE` is set,
+ this will match anything other than ``[0-9_]`` and characters marked as
+ alphanumeric in the Unicode character properties database.
+
+``\Z``
+ Matches only at the end of the string.
+
+Most of the standard escapes supported by Python string literals are also
+accepted by the regular expression parser::
+
+ \a \b \f \n
+ \r \t \v \x
+ \\
+
+Octal escapes are included in a limited form: If the first digit is a 0, or if
+there are three octal digits, it is considered an octal escape. Otherwise, it is
+a group reference. As for string literals, octal escapes are always at most
+three digits in length.
+
+.. % Note the lack of a period in the section title; it causes problems
+.. % with readers of the GNU info version. See http://www.python.org/sf/581414.
+
+
+.. _matching-searching:
+
+Matching vs Searching
+---------------------
+
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+Python offers two different primitive operations based on regular expressions:
+match and search. If you are accustomed to Perl's semantics, the search
+operation is what you're looking for. See the :func:`search` function and
+corresponding method of compiled regular expression objects.
+
+Note that match may differ from search using a regular expression beginning with
+``'^'``: ``'^'`` matches only at the start of the string, or in
+:const:`MULTILINE` mode also immediately following a newline. The "match"
+operation succeeds only if the pattern matches at the start of the string
+regardless of mode, or at the starting position given by the optional *pos*
+argument regardless of whether a newline precedes it.
+
+.. % Examples from Tim Peters:
+
+::
+
+ re.compile("a").match("ba", 1) # succeeds
+ re.compile("^a").search("ba", 1) # fails; 'a' not at start
+ re.compile("^a").search("\na", 1) # fails; 'a' not at start
+ re.compile("^a", re.M).search("\na", 1) # succeeds
+ re.compile("^a", re.M).search("ba", 1) # fails; no preceding \n
+
+
+.. _contents-of-module-re:
+
+Module Contents
+---------------
+
+The module defines several functions, constants, and an exception. Some of the
+functions are simplified versions of the full featured methods for compiled
+regular expressions. Most non-trivial applications always use the compiled
+form.
+
+
+.. function:: compile(pattern[, flags])
+
+ Compile a regular expression pattern into a regular expression object, which can
+ be used for matching using its :func:`match` and :func:`search` methods,
+ described below.
+
+ The expression's behaviour can be modified by specifying a *flags* value.
+ Values can be any of the following variables, combined using bitwise OR (the
+ ``|`` operator).
+
+ The sequence ::
+
+ prog = re.compile(pat)
+ result = prog.match(str)
+
+ is equivalent to ::
+
+ result = re.match(pat, str)
+
+ but the version using :func:`compile` is more efficient when the expression will
+ be used several times in a single program.
+
+ .. % (The compiled version of the last pattern passed to
+ .. % \function{re.match()} or \function{re.search()} is cached, so
+ .. % programs that use only a single regular expression at a time needn't
+ .. % worry about compiling regular expressions.)
+
+
+.. data:: I
+ IGNORECASE
+
+ Perform case-insensitive matching; expressions like ``[A-Z]`` will match
+ lowercase letters, too. This is not affected by the current locale.
+
+
+.. data:: L
+ LOCALE
+
+ Make ``\w``, ``\W``, ``\b``, ``\B``, ``\s`` and ``\S`` dependent on the current
+ locale.
+
+
+.. data:: M
+ MULTILINE
+
+ When specified, the pattern character ``'^'`` matches at the beginning of the
+ string and at the beginning of each line (immediately following each newline);
+ and the pattern character ``'$'`` matches at the end of the string and at the
+ end of each line (immediately preceding each newline). By default, ``'^'``
+ matches only at the beginning of the string, and ``'$'`` only at the end of the
+ string and immediately before the newline (if any) at the end of the string.
+
+
+.. data:: S
+ DOTALL
+
+ Make the ``'.'`` special character match any character at all, including a
+ newline; without this flag, ``'.'`` will match anything *except* a newline.
+
+
+.. data:: U
+ UNICODE
+
+ Make ``\w``, ``\W``, ``\b``, ``\B``, ``\d``, ``\D``, ``\s`` and ``\S`` dependent
+ on the Unicode character properties database.
+
+ .. versionadded:: 2.0
+
+
+.. data:: X
+ VERBOSE
+
+ This flag allows you to write regular expressions that look nicer. Whitespace
+ within the pattern is ignored, except when in a character class or preceded by
+ an unescaped backslash, and, when a line contains a ``'#'`` neither in a
+ character class or preceded by an unescaped backslash, all characters from the
+ leftmost such ``'#'`` through the end of the line are ignored.
+
+ .. % XXX should add an example here
+
+
+.. function:: search(pattern, string[, flags])
+
+ Scan through *string* looking for a location where the regular expression
+ *pattern* produces a match, and return a corresponding :class:`MatchObject`
+ instance. Return ``None`` if no position in the string matches the pattern; note
+ that this is different from finding a zero-length match at some point in the
+ string.
+
+
+.. function:: match(pattern, string[, flags])
+
+ If zero or more characters at the beginning of *string* match the regular
+ expression *pattern*, return a corresponding :class:`MatchObject` instance.
+ Return ``None`` if the string does not match the pattern; note that this is
+ different from a zero-length match.
+
+ .. note::
+
+ If you want to locate a match anywhere in *string*, use :meth:`search` instead.
+
+
+.. function:: split(pattern, string[, maxsplit=0])
+
+ Split *string* by the occurrences of *pattern*. If capturing parentheses are
+ used in *pattern*, then the text of all groups in the pattern are also returned
+ as part of the resulting list. If *maxsplit* is nonzero, at most *maxsplit*
+ splits occur, and the remainder of the string is returned as the final element
+ of the list. (Incompatibility note: in the original Python 1.5 release,
+ *maxsplit* was ignored. This has been fixed in later releases.) ::
+
+ >>> re.split('\W+', 'Words, words, words.')
+ ['Words', 'words', 'words', '']
+ >>> re.split('(\W+)', 'Words, words, words.')
+ ['Words', ', ', 'words', ', ', 'words', '.', '']
+ >>> re.split('\W+', 'Words, words, words.', 1)
+ ['Words', 'words, words.']
+
+
+.. function:: findall(pattern, string[, flags])
+
+ Return a list of all non-overlapping matches of *pattern* in *string*. If one
+ or more groups are present in the pattern, return a list of groups; this will be
+ a list of tuples if the pattern has more than one group. Empty matches are
+ included in the result unless they touch the beginning of another match.
+
+ .. versionadded:: 1.5.2
+
+ .. versionchanged:: 2.4
+ Added the optional flags argument.
+
+
+.. function:: finditer(pattern, string[, flags])
+
+ Return an iterator over all non-overlapping matches for the RE *pattern* in
+ *string*. For each match, the iterator returns a match object. Empty matches
+ are included in the result unless they touch the beginning of another match.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.4
+ Added the optional flags argument.
+
+
+.. function:: sub(pattern, repl, string[, count])
+
+ Return the string obtained by replacing the leftmost non-overlapping occurrences
+ of *pattern* in *string* by the replacement *repl*. If the pattern isn't found,
+ *string* is returned unchanged. *repl* can be a string or a function; if it is
+ a string, any backslash escapes in it are processed. That is, ``\n`` is
+ converted to a single newline character, ``\r`` is converted to a linefeed, and
+ so forth. Unknown escapes such as ``\j`` are left alone. Backreferences, such
+ as ``\6``, are replaced with the substring matched by group 6 in the pattern.
+ For example::
+
+ >>> re.sub(r'def\s+([a-zA-Z_][a-zA-Z_0-9]*)\s*\(\s*\):',
+ ... r'static PyObject*\npy_\1(void)\n{',
+ ... 'def myfunc():')
+ 'static PyObject*\npy_myfunc(void)\n{'
+
+ If *repl* is a function, it is called for every non-overlapping occurrence of
+ *pattern*. The function takes a single match object argument, and returns the
+ replacement string. For example::
+
+ >>> def dashrepl(matchobj):
+ ... if matchobj.group(0) == '-': return ' '
+ ... else: return '-'
+ >>> re.sub('-{1,2}', dashrepl, 'pro----gram-files')
+ 'pro--gram files'
+
+ The pattern may be a string or an RE object; if you need to specify regular
+ expression flags, you must use a RE object, or use embedded modifiers in a
+ pattern; for example, ``sub("(?i)b+", "x", "bbbb BBBB")`` returns ``'x x'``.
+
+ The optional argument *count* is the maximum number of pattern occurrences to be
+ replaced; *count* must be a non-negative integer. If omitted or zero, all
+ occurrences will be replaced. Empty matches for the pattern are replaced only
+ when not adjacent to a previous match, so ``sub('x*', '-', 'abc')`` returns
+ ``'-a-b-c-'``.
+
+ In addition to character escapes and backreferences as described above,
+ ``\g<name>`` will use the substring matched by the group named ``name``, as
+ defined by the ``(?P<name>...)`` syntax. ``\g<number>`` uses the corresponding
+ group number; ``\g<2>`` is therefore equivalent to ``\2``, but isn't ambiguous
+ in a replacement such as ``\g<2>0``. ``\20`` would be interpreted as a
+ reference to group 20, not a reference to group 2 followed by the literal
+ character ``'0'``. The backreference ``\g<0>`` substitutes in the entire
+ substring matched by the RE.
+
+
+.. function:: subn(pattern, repl, string[, count])
+
+ Perform the same operation as :func:`sub`, but return a tuple ``(new_string,
+ number_of_subs_made)``.
+
+
+.. function:: escape(string)
+
+ Return *string* with all non-alphanumerics backslashed; this is useful if you
+ want to match an arbitrary literal string that may have regular expression
+ metacharacters in it.
+
+
+.. exception:: error
+
+ Exception raised when a string passed to one of the functions here is not a
+ valid regular expression (for example, it might contain unmatched parentheses)
+ or when some other error occurs during compilation or matching. It is never an
+ error if a string contains no match for a pattern.
+
+
+.. _re-objects:
+
+Regular Expression Objects
+--------------------------
+
+Compiled regular expression objects support the following methods and
+attributes:
+
+
+.. method:: RegexObject.match(string[, pos[, endpos]])
+
+ If zero or more characters at the beginning of *string* match this regular
+ expression, return a corresponding :class:`MatchObject` instance. Return
+ ``None`` if the string does not match the pattern; note that this is different
+ from a zero-length match.
+
+ .. note::
+
+ If you want to locate a match anywhere in *string*, use :meth:`search` instead.
+
+ The optional second parameter *pos* gives an index in the string where the
+ search is to start; it defaults to ``0``. This is not completely equivalent to
+ slicing the string; the ``'^'`` pattern character matches at the real beginning
+ of the string and at positions just after a newline, but not necessarily at the
+ index where the search is to start.
+
+ The optional parameter *endpos* limits how far the string will be searched; it
+ will be as if the string is *endpos* characters long, so only the characters
+ from *pos* to ``endpos - 1`` will be searched for a match. If *endpos* is less
+ than *pos*, no match will be found, otherwise, if *rx* is a compiled regular
+ expression object, ``rx.match(string, 0, 50)`` is equivalent to
+ ``rx.match(string[:50], 0)``.
+
+
+.. method:: RegexObject.search(string[, pos[, endpos]])
+
+ Scan through *string* looking for a location where this regular expression
+ produces a match, and return a corresponding :class:`MatchObject` instance.
+ Return ``None`` if no position in the string matches the pattern; note that this
+ is different from finding a zero-length match at some point in the string.
+
+ The optional *pos* and *endpos* parameters have the same meaning as for the
+ :meth:`match` method.
+
+
+.. method:: RegexObject.split(string[, maxsplit=0])
+
+ Identical to the :func:`split` function, using the compiled pattern.
+
+
+.. method:: RegexObject.findall(string[, pos[, endpos]])
+
+ Identical to the :func:`findall` function, using the compiled pattern.
+
+
+.. method:: RegexObject.finditer(string[, pos[, endpos]])
+
+ Identical to the :func:`finditer` function, using the compiled pattern.
+
+
+.. method:: RegexObject.sub(repl, string[, count=0])
+
+ Identical to the :func:`sub` function, using the compiled pattern.
+
+
+.. method:: RegexObject.subn(repl, string[, count=0])
+
+ Identical to the :func:`subn` function, using the compiled pattern.
+
+
+.. attribute:: RegexObject.flags
+
+ The flags argument used when the RE object was compiled, or ``0`` if no flags
+ were provided.
+
+
+.. attribute:: RegexObject.groupindex
+
+ A dictionary mapping any symbolic group names defined by ``(?P<id>)`` to group
+ numbers. The dictionary is empty if no symbolic groups were used in the
+ pattern.
+
+
+.. attribute:: RegexObject.pattern
+
+ The pattern string from which the RE object was compiled.
+
+
+.. _match-objects:
+
+Match Objects
+-------------
+
+:class:`MatchObject` instances support the following methods and attributes:
+
+
+.. method:: MatchObject.expand(template)
+
+ Return the string obtained by doing backslash substitution on the template
+ string *template*, as done by the :meth:`sub` method. Escapes such as ``\n`` are
+ converted to the appropriate characters, and numeric backreferences (``\1``,
+ ``\2``) and named backreferences (``\g<1>``, ``\g<name>``) are replaced by the
+ contents of the corresponding group.
+
+
+.. method:: MatchObject.group([group1, ...])
+
+ Returns one or more subgroups of the match. If there is a single argument, the
+ result is a single string; if there are multiple arguments, the result is a
+ tuple with one item per argument. Without arguments, *group1* defaults to zero
+ (the whole match is returned). If a *groupN* argument is zero, the corresponding
+ return value is the entire matching string; if it is in the inclusive range
+ [1..99], it is the string matching the corresponding parenthesized group. If a
+ group number is negative or larger than the number of groups defined in the
+ pattern, an :exc:`IndexError` exception is raised. If a group is contained in a
+ part of the pattern that did not match, the corresponding result is ``None``.
+ If a group is contained in a part of the pattern that matched multiple times,
+ the last match is returned.
+
+ If the regular expression uses the ``(?P<name>...)`` syntax, the *groupN*
+ arguments may also be strings identifying groups by their group name. If a
+ string argument is not used as a group name in the pattern, an :exc:`IndexError`
+ exception is raised.
+
+ A moderately complicated example::
+
+ m = re.match(r"(?P<int>\d+)\.(\d*)", '3.14')
+
+ After performing this match, ``m.group(1)`` is ``'3'``, as is
+ ``m.group('int')``, and ``m.group(2)`` is ``'14'``.
+
+
+.. method:: MatchObject.groups([default])
+
+ Return a tuple containing all the subgroups of the match, from 1 up to however
+ many groups are in the pattern. The *default* argument is used for groups that
+ did not participate in the match; it defaults to ``None``. (Incompatibility
+ note: in the original Python 1.5 release, if the tuple was one element long, a
+ string would be returned instead. In later versions (from 1.5.1 on), a
+ singleton tuple is returned in such cases.)
+
+
+.. method:: MatchObject.groupdict([default])
+
+ Return a dictionary containing all the *named* subgroups of the match, keyed by
+ the subgroup name. The *default* argument is used for groups that did not
+ participate in the match; it defaults to ``None``.
+
+
+.. method:: MatchObject.start([group])
+ MatchObject.end([group])
+
+ Return the indices of the start and end of the substring matched by *group*;
+ *group* defaults to zero (meaning the whole matched substring). Return ``-1`` if
+ *group* exists but did not contribute to the match. For a match object *m*, and
+ a group *g* that did contribute to the match, the substring matched by group *g*
+ (equivalent to ``m.group(g)``) is ::
+
+ m.string[m.start(g):m.end(g)]
+
+ Note that ``m.start(group)`` will equal ``m.end(group)`` if *group* matched a
+ null string. For example, after ``m = re.search('b(c?)', 'cba')``,
+ ``m.start(0)`` is 1, ``m.end(0)`` is 2, ``m.start(1)`` and ``m.end(1)`` are both
+ 2, and ``m.start(2)`` raises an :exc:`IndexError` exception.
+
+
+.. method:: MatchObject.span([group])
+
+ For :class:`MatchObject` *m*, return the 2-tuple ``(m.start(group),
+ m.end(group))``. Note that if *group* did not contribute to the match, this is
+ ``(-1, -1)``. Again, *group* defaults to zero.
+
+
+.. attribute:: MatchObject.pos
+
+ The value of *pos* which was passed to the :func:`search` or :func:`match`
+ method of the :class:`RegexObject`. This is the index into the string at which
+ the RE engine started looking for a match.
+
+
+.. attribute:: MatchObject.endpos
+
+ The value of *endpos* which was passed to the :func:`search` or :func:`match`
+ method of the :class:`RegexObject`. This is the index into the string beyond
+ which the RE engine will not go.
+
+
+.. attribute:: MatchObject.lastindex
+
+ The integer index of the last matched capturing group, or ``None`` if no group
+ was matched at all. For example, the expressions ``(a)b``, ``((a)(b))``, and
+ ``((ab))`` will have ``lastindex == 1`` if applied to the string ``'ab'``, while
+ the expression ``(a)(b)`` will have ``lastindex == 2``, if applied to the same
+ string.
+
+
+.. attribute:: MatchObject.lastgroup
+
+ The name of the last matched capturing group, or ``None`` if the group didn't
+ have a name, or if no group was matched at all.
+
+
+.. attribute:: MatchObject.re
+
+ The regular expression object whose :meth:`match` or :meth:`search` method
+ produced this :class:`MatchObject` instance.
+
+
+.. attribute:: MatchObject.string
+
+ The string passed to :func:`match` or :func:`search`.
+
+
+Examples
+--------
+
+**Simulating scanf()**
+
+.. index:: single: scanf()
+
+Python does not currently have an equivalent to :cfunc:`scanf`. Regular
+expressions are generally more powerful, though also more verbose, than
+:cfunc:`scanf` format strings. The table below offers some more-or-less
+equivalent mappings between :cfunc:`scanf` format tokens and regular
+expressions.
+
++--------------------------------+---------------------------------------------+
+| :cfunc:`scanf` Token | Regular Expression |
++================================+=============================================+
+| ``%c`` | ``.`` |
++--------------------------------+---------------------------------------------+
+| ``%5c`` | ``.{5}`` |
++--------------------------------+---------------------------------------------+
+| ``%d`` | ``[-+]?\d+`` |
++--------------------------------+---------------------------------------------+
+| ``%e``, ``%E``, ``%f``, ``%g`` | ``[-+]?(\d+(\.\d*)?|\.\d+)([eE][-+]?\d+)?`` |
++--------------------------------+---------------------------------------------+
+| ``%i`` | ``[-+]?(0[xX][\dA-Fa-f]+|0[0-7]*|\d+)`` |
++--------------------------------+---------------------------------------------+
+| ``%o`` | ``0[0-7]*`` |
++--------------------------------+---------------------------------------------+
+| ``%s`` | ``\S+`` |
++--------------------------------+---------------------------------------------+
+| ``%u`` | ``\d+`` |
++--------------------------------+---------------------------------------------+
+| ``%x``, ``%X`` | ``0[xX][\dA-Fa-f]+`` |
++--------------------------------+---------------------------------------------+
+
+To extract the filename and numbers from a string like ::
+
+ /usr/sbin/sendmail - 0 errors, 4 warnings
+
+you would use a :cfunc:`scanf` format like ::
+
+ %s - %d errors, %d warnings
+
+The equivalent regular expression would be ::
+
+ (\S+) - (\d+) errors, (\d+) warnings
+
+**Avoiding recursion**
+
+If you create regular expressions that require the engine to perform a lot of
+recursion, you may encounter a :exc:`RuntimeError` exception with the message
+``maximum recursion limit`` exceeded. For example, ::
+
+ >>> import re
+ >>> s = 'Begin ' + 1000*'a very long string ' + 'end'
+ >>> re.match('Begin (\w| )*? end', s).end()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "/usr/local/lib/python2.5/re.py", line 132, in match
+ return _compile(pattern, flags).match(string)
+ RuntimeError: maximum recursion limit exceeded
+
+You can often restructure your regular expression to avoid recursion.
+
+Starting with Python 2.3, simple uses of the ``*?`` pattern are special-cased to
+avoid recursion. Thus, the above regular expression can avoid recursion by
+being recast as ``Begin [a-zA-Z0-9_ ]*?end``. As a further benefit, such
+regular expressions will run faster than their recursive equivalents.
+
diff --git a/Doc/library/readline.rst b/Doc/library/readline.rst
new file mode 100644
index 0000000000..9a40747b4f
--- /dev/null
+++ b/Doc/library/readline.rst
@@ -0,0 +1,222 @@
+
+:mod:`readline` --- GNU readline interface
+==========================================
+
+.. module:: readline
+ :platform: Unix
+ :synopsis: GNU readline support for Python.
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+The :mod:`readline` module defines a number of functions to facilitate
+completion and reading/writing of history files from the Python interpreter.
+This module can be used directly or via the :mod:`rlcompleter` module. Settings
+made using this module affect the behaviour of both the interpreter's
+interactive prompt and the prompts offered by the :func:`raw_input` and
+:func:`input` built-in functions.
+
+The :mod:`readline` module defines the following functions:
+
+
+.. function:: parse_and_bind(string)
+
+ Parse and execute single line of a readline init file.
+
+
+.. function:: get_line_buffer()
+
+ Return the current contents of the line buffer.
+
+
+.. function:: insert_text(string)
+
+ Insert text into the command line.
+
+
+.. function:: read_init_file([filename])
+
+ Parse a readline initialization file. The default filename is the last filename
+ used.
+
+
+.. function:: read_history_file([filename])
+
+ Load a readline history file. The default filename is :file:`~/.history`.
+
+
+.. function:: write_history_file([filename])
+
+ Save a readline history file. The default filename is :file:`~/.history`.
+
+
+.. function:: clear_history()
+
+ Clear the current history. (Note: this function is not available if the
+ installed version of GNU readline doesn't support it.)
+
+ .. versionadded:: 2.4
+
+
+.. function:: get_history_length()
+
+ Return the desired length of the history file. Negative values imply unlimited
+ history file size.
+
+
+.. function:: set_history_length(length)
+
+ Set the number of lines to save in the history file. :func:`write_history_file`
+ uses this value to truncate the history file when saving. Negative values imply
+ unlimited history file size.
+
+
+.. function:: get_current_history_length()
+
+ Return the number of lines currently in the history. (This is different from
+ :func:`get_history_length`, which returns the maximum number of lines that will
+ be written to a history file.)
+
+ .. versionadded:: 2.3
+
+
+.. function:: get_history_item(index)
+
+ Return the current contents of history item at *index*.
+
+ .. versionadded:: 2.3
+
+
+.. function:: remove_history_item(pos)
+
+ Remove history item specified by its position from the history.
+
+ .. versionadded:: 2.4
+
+
+.. function:: replace_history_item(pos, line)
+
+ Replace history item specified by its position with the given line.
+
+ .. versionadded:: 2.4
+
+
+.. function:: redisplay()
+
+ Change what's displayed on the screen to reflect the current contents of the
+ line buffer.
+
+ .. versionadded:: 2.3
+
+
+.. function:: set_startup_hook([function])
+
+ Set or remove the startup_hook function. If *function* is specified, it will be
+ used as the new startup_hook function; if omitted or ``None``, any hook function
+ already installed is removed. The startup_hook function is called with no
+ arguments just before readline prints the first prompt.
+
+
+.. function:: set_pre_input_hook([function])
+
+ Set or remove the pre_input_hook function. If *function* is specified, it will
+ be used as the new pre_input_hook function; if omitted or ``None``, any hook
+ function already installed is removed. The pre_input_hook function is called
+ with no arguments after the first prompt has been printed and just before
+ readline starts reading input characters.
+
+
+.. function:: set_completer([function])
+
+ Set or remove the completer function. If *function* is specified, it will be
+ used as the new completer function; if omitted or ``None``, any completer
+ function already installed is removed. The completer function is called as
+ ``function(text, state)``, for *state* in ``0``, ``1``, ``2``, ..., until it
+ returns a non-string value. It should return the next possible completion
+ starting with *text*.
+
+
+.. function:: get_completer()
+
+ Get the completer function, or ``None`` if no completer function has been set.
+
+ .. versionadded:: 2.3
+
+
+.. function:: get_begidx()
+
+ Get the beginning index of the readline tab-completion scope.
+
+
+.. function:: get_endidx()
+
+ Get the ending index of the readline tab-completion scope.
+
+
+.. function:: set_completer_delims(string)
+
+ Set the readline word delimiters for tab-completion.
+
+
+.. function:: get_completer_delims()
+
+ Get the readline word delimiters for tab-completion.
+
+
+.. function:: add_history(line)
+
+ Append a line to the history buffer, as if it was the last line typed.
+
+
+.. seealso::
+
+ Module :mod:`rlcompleter`
+ Completion of Python identifiers at the interactive prompt.
+
+
+.. _readline-example:
+
+Example
+-------
+
+The following example demonstrates how to use the :mod:`readline` module's
+history reading and writing functions to automatically load and save a history
+file named :file:`.pyhist` from the user's home directory. The code below would
+normally be executed automatically during interactive sessions from the user's
+:envvar:`PYTHONSTARTUP` file. ::
+
+ import os
+ histfile = os.path.join(os.environ["HOME"], ".pyhist")
+ try:
+ readline.read_history_file(histfile)
+ except IOError:
+ pass
+ import atexit
+ atexit.register(readline.write_history_file, histfile)
+ del os, histfile
+
+The following example extends the :class:`code.InteractiveConsole` class to
+support history save/restore. ::
+
+ import code
+ import readline
+ import atexit
+ import os
+
+ class HistoryConsole(code.InteractiveConsole):
+ def __init__(self, locals=None, filename="<console>",
+ histfile=os.path.expanduser("~/.console-history")):
+ code.InteractiveConsole.__init__(self)
+ self.init_history(histfile)
+
+ def init_history(self, histfile):
+ readline.parse_and_bind("tab: complete")
+ if hasattr(readline, "read_history_file"):
+ try:
+ readline.read_history_file(histfile)
+ except IOError:
+ pass
+ atexit.register(self.save_history, histfile)
+
+ def save_history(self, histfile):
+ readline.write_history_file(histfile)
+
diff --git a/Doc/library/repr.rst b/Doc/library/repr.rst
new file mode 100644
index 0000000000..493e2b32f1
--- /dev/null
+++ b/Doc/library/repr.rst
@@ -0,0 +1,136 @@
+
+:mod:`repr` --- Alternate :func:`repr` implementation
+=====================================================
+
+.. module:: repr
+ :synopsis: Alternate repr() implementation with size limits.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`repr` module provides a means for producing object representations
+with limits on the size of the resulting strings. This is used in the Python
+debugger and may be useful in other contexts as well.
+
+This module provides a class, an instance, and a function:
+
+
+.. class:: Repr()
+
+ Class which provides formatting services useful in implementing functions
+ similar to the built-in :func:`repr`; size limits for different object types
+ are added to avoid the generation of representations which are excessively long.
+
+
+.. data:: aRepr
+
+ This is an instance of :class:`Repr` which is used to provide the :func:`repr`
+ function described below. Changing the attributes of this object will affect
+ the size limits used by :func:`repr` and the Python debugger.
+
+
+.. function:: repr(obj)
+
+ This is the :meth:`repr` method of ``aRepr``. It returns a string similar to
+ that returned by the built-in function of the same name, but with limits on
+ most sizes.
+
+
+.. _repr-objects:
+
+Repr Objects
+------------
+
+:class:`Repr` instances provide several members which can be used to provide
+size limits for the representations of different object types, and methods
+which format specific object types.
+
+
+.. attribute:: Repr.maxlevel
+
+ Depth limit on the creation of recursive representations. The default is ``6``.
+
+
+.. attribute:: Repr.maxdict
+ Repr.maxlist
+ Repr.maxtuple
+ Repr.maxset
+ Repr.maxfrozenset
+ Repr.maxdeque
+ Repr.maxarray
+
+ Limits on the number of entries represented for the named object type. The
+ default is ``4`` for :attr:`maxdict`, ``5`` for :attr:`maxarray`, and ``6`` for
+ the others.
+
+ .. versionadded:: 2.4
+ :attr:`maxset`, :attr:`maxfrozenset`, and :attr:`set`.
+
+
+.. attribute:: Repr.maxlong
+
+ Maximum number of characters in the representation for a long integer. Digits
+ are dropped from the middle. The default is ``40``.
+
+
+.. attribute:: Repr.maxstring
+
+ Limit on the number of characters in the representation of the string. Note
+ that the "normal" representation of the string is used as the character source:
+ if escape sequences are needed in the representation, these may be mangled when
+ the representation is shortened. The default is ``30``.
+
+
+.. attribute:: Repr.maxother
+
+ This limit is used to control the size of object types for which no specific
+ formatting method is available on the :class:`Repr` object. It is applied in a
+ similar manner as :attr:`maxstring`. The default is ``20``.
+
+
+.. method:: Repr.repr(obj)
+
+ The equivalent to the built-in :func:`repr` that uses the formatting imposed by
+ the instance.
+
+
+.. method:: Repr.repr1(obj, level)
+
+ Recursive implementation used by :meth:`repr`. This uses the type of *obj* to
+ determine which formatting method to call, passing it *obj* and *level*. The
+ type-specific methods should call :meth:`repr1` to perform recursive formatting,
+ with ``level - 1`` for the value of *level* in the recursive call.
+
+
+.. method:: Repr.repr_TYPE(obj, level)
+ :noindex:
+
+ Formatting methods for specific types are implemented as methods with a name
+ based on the type name. In the method name, **TYPE** is replaced by
+ ``string.join(string.split(type(obj).__name__, '_'))``. Dispatch to these
+ methods is handled by :meth:`repr1`. Type-specific methods which need to
+ recursively format a value should call ``self.repr1(subobj, level - 1)``.
+
+
+.. _subclassing-reprs:
+
+Subclassing Repr Objects
+------------------------
+
+The use of dynamic dispatching by :meth:`Repr.repr1` allows subclasses of
+:class:`Repr` to add support for additional built-in object types or to modify
+the handling of types already supported. This example shows how special support
+for file objects could be added::
+
+ import repr
+ import sys
+
+ class MyRepr(repr.Repr):
+ def repr_file(self, obj, level):
+ if obj.name in ['<stdin>', '<stdout>', '<stderr>']:
+ return obj.name
+ else:
+ return `obj`
+
+ aRepr = MyRepr()
+ print aRepr.repr(sys.stdin) # prints '<stdin>'
+
diff --git a/Doc/library/resource.rst b/Doc/library/resource.rst
new file mode 100644
index 0000000000..834daceb8c
--- /dev/null
+++ b/Doc/library/resource.rst
@@ -0,0 +1,238 @@
+
+:mod:`resource` --- Resource usage information
+==============================================
+
+.. module:: resource
+ :platform: Unix
+ :synopsis: An interface to provide resource usage information on the current process.
+.. moduleauthor:: Jeremy Hylton <jeremy@alum.mit.edu>
+.. sectionauthor:: Jeremy Hylton <jeremy@alum.mit.edu>
+
+
+This module provides basic mechanisms for measuring and controlling system
+resources utilized by a program.
+
+Symbolic constants are used to specify particular system resources and to
+request usage information about either the current process or its children.
+
+A single exception is defined for errors:
+
+
+.. exception:: error
+
+ The functions described below may raise this error if the underlying system call
+ failures unexpectedly.
+
+
+Resource Limits
+---------------
+
+Resources usage can be limited using the :func:`setrlimit` function described
+below. Each resource is controlled by a pair of limits: a soft limit and a hard
+limit. The soft limit is the current limit, and may be lowered or raised by a
+process over time. The soft limit can never exceed the hard limit. The hard
+limit can be lowered to any value greater than the soft limit, but not raised.
+(Only processes with the effective UID of the super-user can raise a hard
+limit.)
+
+The specific resources that can be limited are system dependent. They are
+described in the :manpage:`getrlimit(2)` man page. The resources listed below
+are supported when the underlying operating system supports them; resources
+which cannot be checked or controlled by the operating system are not defined in
+this module for those platforms.
+
+
+.. function:: getrlimit(resource)
+
+ Returns a tuple ``(soft, hard)`` with the current soft and hard limits of
+ *resource*. Raises :exc:`ValueError` if an invalid resource is specified, or
+ :exc:`error` if the underlying system call fails unexpectedly.
+
+
+.. function:: setrlimit(resource, limits)
+
+ Sets new limits of consumption of *resource*. The *limits* argument must be a
+ tuple ``(soft, hard)`` of two integers describing the new limits. A value of
+ ``-1`` can be used to specify the maximum possible upper limit.
+
+ Raises :exc:`ValueError` if an invalid resource is specified, if the new soft
+ limit exceeds the hard limit, or if a process tries to raise its hard limit
+ (unless the process has an effective UID of super-user). Can also raise
+ :exc:`error` if the underlying system call fails.
+
+These symbols define resources whose consumption can be controlled using the
+:func:`setrlimit` and :func:`getrlimit` functions described below. The values of
+these symbols are exactly the constants used by C programs.
+
+The Unix man page for :manpage:`getrlimit(2)` lists the available resources.
+Note that not all systems use the same symbol or same value to denote the same
+resource. This module does not attempt to mask platform differences --- symbols
+not defined for a platform will not be available from this module on that
+platform.
+
+
+.. data:: RLIMIT_CORE
+
+ The maximum size (in bytes) of a core file that the current process can create.
+ This may result in the creation of a partial core file if a larger core would be
+ required to contain the entire process image.
+
+
+.. data:: RLIMIT_CPU
+
+ The maximum amount of processor time (in seconds) that a process can use. If
+ this limit is exceeded, a :const:`SIGXCPU` signal is sent to the process. (See
+ the :mod:`signal` module documentation for information about how to catch this
+ signal and do something useful, e.g. flush open files to disk.)
+
+
+.. data:: RLIMIT_FSIZE
+
+ The maximum size of a file which the process may create. This only affects the
+ stack of the main thread in a multi-threaded process.
+
+
+.. data:: RLIMIT_DATA
+
+ The maximum size (in bytes) of the process's heap.
+
+
+.. data:: RLIMIT_STACK
+
+ The maximum size (in bytes) of the call stack for the current process.
+
+
+.. data:: RLIMIT_RSS
+
+ The maximum resident set size that should be made available to the process.
+
+
+.. data:: RLIMIT_NPROC
+
+ The maximum number of processes the current process may create.
+
+
+.. data:: RLIMIT_NOFILE
+
+ The maximum number of open file descriptors for the current process.
+
+
+.. data:: RLIMIT_OFILE
+
+ The BSD name for :const:`RLIMIT_NOFILE`.
+
+
+.. data:: RLIMIT_MEMLOCK
+
+ The maximum address space which may be locked in memory.
+
+
+.. data:: RLIMIT_VMEM
+
+ The largest area of mapped memory which the process may occupy.
+
+
+.. data:: RLIMIT_AS
+
+ The maximum area (in bytes) of address space which may be taken by the process.
+
+
+Resource Usage
+--------------
+
+These functions are used to retrieve resource usage information:
+
+
+.. function:: getrusage(who)
+
+ This function returns an object that describes the resources consumed by either
+ the current process or its children, as specified by the *who* parameter. The
+ *who* parameter should be specified using one of the :const:`RUSAGE_\*`
+ constants described below.
+
+ The fields of the return value each describe how a particular system resource
+ has been used, e.g. amount of time spent running is user mode or number of times
+ the process was swapped out of main memory. Some values are dependent on the
+ clock tick internal, e.g. the amount of memory the process is using.
+
+ For backward compatibility, the return value is also accessible as a tuple of 16
+ elements.
+
+ The fields :attr:`ru_utime` and :attr:`ru_stime` of the return value are
+ floating point values representing the amount of time spent executing in user
+ mode and the amount of time spent executing in system mode, respectively. The
+ remaining values are integers. Consult the :manpage:`getrusage(2)` man page for
+ detailed information about these values. A brief summary is presented here:
+
+ +--------+---------------------+-------------------------------+
+ | Index | Field | Resource |
+ +========+=====================+===============================+
+ | ``0`` | :attr:`ru_utime` | time in user mode (float) |
+ +--------+---------------------+-------------------------------+
+ | ``1`` | :attr:`ru_stime` | time in system mode (float) |
+ +--------+---------------------+-------------------------------+
+ | ``2`` | :attr:`ru_maxrss` | maximum resident set size |
+ +--------+---------------------+-------------------------------+
+ | ``3`` | :attr:`ru_ixrss` | shared memory size |
+ +--------+---------------------+-------------------------------+
+ | ``4`` | :attr:`ru_idrss` | unshared memory size |
+ +--------+---------------------+-------------------------------+
+ | ``5`` | :attr:`ru_isrss` | unshared stack size |
+ +--------+---------------------+-------------------------------+
+ | ``6`` | :attr:`ru_minflt` | page faults not requiring I/O |
+ +--------+---------------------+-------------------------------+
+ | ``7`` | :attr:`ru_majflt` | page faults requiring I/O |
+ +--------+---------------------+-------------------------------+
+ | ``8`` | :attr:`ru_nswap` | number of swap outs |
+ +--------+---------------------+-------------------------------+
+ | ``9`` | :attr:`ru_inblock` | block input operations |
+ +--------+---------------------+-------------------------------+
+ | ``10`` | :attr:`ru_oublock` | block output operations |
+ +--------+---------------------+-------------------------------+
+ | ``11`` | :attr:`ru_msgsnd` | messages sent |
+ +--------+---------------------+-------------------------------+
+ | ``12`` | :attr:`ru_msgrcv` | messages received |
+ +--------+---------------------+-------------------------------+
+ | ``13`` | :attr:`ru_nsignals` | signals received |
+ +--------+---------------------+-------------------------------+
+ | ``14`` | :attr:`ru_nvcsw` | voluntary context switches |
+ +--------+---------------------+-------------------------------+
+ | ``15`` | :attr:`ru_nivcsw` | involuntary context switches |
+ +--------+---------------------+-------------------------------+
+
+ This function will raise a :exc:`ValueError` if an invalid *who* parameter is
+ specified. It may also raise :exc:`error` exception in unusual circumstances.
+
+ .. versionchanged:: 2.3
+ Added access to values as attributes of the returned object.
+
+
+.. function:: getpagesize()
+
+ Returns the number of bytes in a system page. (This need not be the same as the
+ hardware page size.) This function is useful for determining the number of bytes
+ of memory a process is using. The third element of the tuple returned by
+ :func:`getrusage` describes memory usage in pages; multiplying by page size
+ produces number of bytes.
+
+The following :const:`RUSAGE_\*` symbols are passed to the :func:`getrusage`
+function to specify which processes information should be provided for.
+
+
+.. data:: RUSAGE_SELF
+
+ :const:`RUSAGE_SELF` should be used to request information pertaining only to
+ the process itself.
+
+
+.. data:: RUSAGE_CHILDREN
+
+ Pass to :func:`getrusage` to request resource information for child processes of
+ the calling process.
+
+
+.. data:: RUSAGE_BOTH
+
+ Pass to :func:`getrusage` to request resources consumed by both the current
+ process and child processes. May not be available on all systems.
+
diff --git a/Doc/library/rfc822.rst b/Doc/library/rfc822.rst
new file mode 100644
index 0000000000..fa25ba5b1b
--- /dev/null
+++ b/Doc/library/rfc822.rst
@@ -0,0 +1,351 @@
+
+:mod:`rfc822` --- Parse RFC 2822 mail headers
+=============================================
+
+.. module:: rfc822
+ :synopsis: Parse 2822 style mail messages.
+
+
+.. deprecated:: 2.3
+ The :mod:`email` package should be used in preference to the :mod:`rfc822`
+ module. This module is present only to maintain backward compatibility.
+
+This module defines a class, :class:`Message`, which represents an "email
+message" as defined by the Internet standard :rfc:`2822`. [#]_ Such messages
+consist of a collection of message headers, and a message body. This module
+also defines a helper class :class:`AddressList` for parsing :rfc:`2822`
+addresses. Please refer to the RFC for information on the specific syntax of
+:rfc:`2822` messages.
+
+.. index:: module: mailbox
+
+The :mod:`mailbox` module provides classes to read mailboxes produced by
+various end-user mail programs.
+
+
+.. class:: Message(file[, seekable])
+
+ A :class:`Message` instance is instantiated with an input object as parameter.
+ Message relies only on the input object having a :meth:`readline` method; in
+ particular, ordinary file objects qualify. Instantiation reads headers from the
+ input object up to a delimiter line (normally a blank line) and stores them in
+ the instance. The message body, following the headers, is not consumed.
+
+ This class can work with any input object that supports a :meth:`readline`
+ method. If the input object has seek and tell capability, the
+ :meth:`rewindbody` method will work; also, illegal lines will be pushed back
+ onto the input stream. If the input object lacks seek but has an :meth:`unread`
+ method that can push back a line of input, :class:`Message` will use that to
+ push back illegal lines. Thus this class can be used to parse messages coming
+ from a buffered stream.
+
+ The optional *seekable* argument is provided as a workaround for certain stdio
+ libraries in which :cfunc:`tell` discards buffered data before discovering that
+ the :cfunc:`lseek` system call doesn't work. For maximum portability, you
+ should set the seekable argument to zero to prevent that initial :meth:`tell`
+ when passing in an unseekable object such as a file object created from a socket
+ object.
+
+ Input lines as read from the file may either be terminated by CR-LF or by a
+ single linefeed; a terminating CR-LF is replaced by a single linefeed before the
+ line is stored.
+
+ All header matching is done independent of upper or lower case; e.g.
+ ``m['From']``, ``m['from']`` and ``m['FROM']`` all yield the same result.
+
+
+.. class:: AddressList(field)
+
+ You may instantiate the :class:`AddressList` helper class using a single string
+ parameter, a comma-separated list of :rfc:`2822` addresses to be parsed. (The
+ parameter ``None`` yields an empty list.)
+
+
+.. function:: quote(str)
+
+ Return a new string with backslashes in *str* replaced by two backslashes and
+ double quotes replaced by backslash-double quote.
+
+
+.. function:: unquote(str)
+
+ Return a new string which is an *unquoted* version of *str*. If *str* ends and
+ begins with double quotes, they are stripped off. Likewise if *str* ends and
+ begins with angle brackets, they are stripped off.
+
+
+.. function:: parseaddr(address)
+
+ Parse *address*, which should be the value of some address-containing field such
+ as :mailheader:`To` or :mailheader:`Cc`, into its constituent "realname" and
+ "email address" parts. Returns a tuple of that information, unless the parse
+ fails, in which case a 2-tuple ``(None, None)`` is returned.
+
+
+.. function:: dump_address_pair(pair)
+
+ The inverse of :meth:`parseaddr`, this takes a 2-tuple of the form ``(realname,
+ email_address)`` and returns the string value suitable for a :mailheader:`To` or
+ :mailheader:`Cc` header. If the first element of *pair* is false, then the
+ second element is returned unmodified.
+
+
+.. function:: parsedate(date)
+
+ Attempts to parse a date according to the rules in :rfc:`2822`. however, some
+ mailers don't follow that format as specified, so :func:`parsedate` tries to
+ guess correctly in such cases. *date* is a string containing an :rfc:`2822`
+ date, such as ``'Mon, 20 Nov 1995 19:12:08 -0500'``. If it succeeds in parsing
+ the date, :func:`parsedate` returns a 9-tuple that can be passed directly to
+ :func:`time.mktime`; otherwise ``None`` will be returned. Note that indexes 6,
+ 7, and 8 of the result tuple are not usable.
+
+
+.. function:: parsedate_tz(date)
+
+ Performs the same function as :func:`parsedate`, but returns either ``None`` or
+ a 10-tuple; the first 9 elements make up a tuple that can be passed directly to
+ :func:`time.mktime`, and the tenth is the offset of the date's timezone from UTC
+ (which is the official term for Greenwich Mean Time). (Note that the sign of
+ the timezone offset is the opposite of the sign of the ``time.timezone``
+ variable for the same timezone; the latter variable follows the POSIX standard
+ while this module follows :rfc:`2822`.) If the input string has no timezone,
+ the last element of the tuple returned is ``None``. Note that indexes 6, 7, and
+ 8 of the result tuple are not usable.
+
+
+.. function:: mktime_tz(tuple)
+
+ Turn a 10-tuple as returned by :func:`parsedate_tz` into a UTC timestamp. If
+ the timezone item in the tuple is ``None``, assume local time. Minor
+ deficiency: this first interprets the first 8 elements as a local time and then
+ compensates for the timezone difference; this may yield a slight error around
+ daylight savings time switch dates. Not enough to worry about for common use.
+
+
+.. seealso::
+
+ Module :mod:`email`
+ Comprehensive email handling package; supersedes the :mod:`rfc822` module.
+
+ Module :mod:`mailbox`
+ Classes to read various mailbox formats produced by end-user mail programs.
+
+ Module :mod:`mimetools`
+ Subclass of :class:`rfc822.Message` that handles MIME encoded messages.
+
+
+.. _message-objects:
+
+Message Objects
+---------------
+
+A :class:`Message` instance has the following methods:
+
+
+.. method:: Message.rewindbody()
+
+ Seek to the start of the message body. This only works if the file object is
+ seekable.
+
+
+.. method:: Message.isheader(line)
+
+ Returns a line's canonicalized fieldname (the dictionary key that will be used
+ to index it) if the line is a legal :rfc:`2822` header; otherwise returns
+ ``None`` (implying that parsing should stop here and the line be pushed back on
+ the input stream). It is sometimes useful to override this method in a
+ subclass.
+
+
+.. method:: Message.islast(line)
+
+ Return true if the given line is a delimiter on which Message should stop. The
+ delimiter line is consumed, and the file object's read location positioned
+ immediately after it. By default this method just checks that the line is
+ blank, but you can override it in a subclass.
+
+
+.. method:: Message.iscomment(line)
+
+ Return ``True`` if the given line should be ignored entirely, just skipped. By
+ default this is a stub that always returns ``False``, but you can override it in
+ a subclass.
+
+
+.. method:: Message.getallmatchingheaders(name)
+
+ Return a list of lines consisting of all headers matching *name*, if any. Each
+ physical line, whether it is a continuation line or not, is a separate list
+ item. Return the empty list if no header matches *name*.
+
+
+.. method:: Message.getfirstmatchingheader(name)
+
+ Return a list of lines comprising the first header matching *name*, and its
+ continuation line(s), if any. Return ``None`` if there is no header matching
+ *name*.
+
+
+.. method:: Message.getrawheader(name)
+
+ Return a single string consisting of the text after the colon in the first
+ header matching *name*. This includes leading whitespace, the trailing
+ linefeed, and internal linefeeds and whitespace if there any continuation
+ line(s) were present. Return ``None`` if there is no header matching *name*.
+
+
+.. method:: Message.getheader(name[, default])
+
+ Like ``getrawheader(name)``, but strip leading and trailing whitespace.
+ Internal whitespace is not stripped. The optional *default* argument can be
+ used to specify a different default to be returned when there is no header
+ matching *name*.
+
+
+.. method:: Message.get(name[, default])
+
+ An alias for :meth:`getheader`, to make the interface more compatible with
+ regular dictionaries.
+
+
+.. method:: Message.getaddr(name)
+
+ Return a pair ``(full name, email address)`` parsed from the string returned by
+ ``getheader(name)``. If no header matching *name* exists, return ``(None,
+ None)``; otherwise both the full name and the address are (possibly empty)
+ strings.
+
+ Example: If *m*'s first :mailheader:`From` header contains the string
+ ``'jack@cwi.nl (Jack Jansen)'``, then ``m.getaddr('From')`` will yield the pair
+ ``('Jack Jansen', 'jack@cwi.nl')``. If the header contained ``'Jack Jansen
+ <jack@cwi.nl>'`` instead, it would yield the exact same result.
+
+
+.. method:: Message.getaddrlist(name)
+
+ This is similar to ``getaddr(list)``, but parses a header containing a list of
+ email addresses (e.g. a :mailheader:`To` header) and returns a list of ``(full
+ name, email address)`` pairs (even if there was only one address in the header).
+ If there is no header matching *name*, return an empty list.
+
+ If multiple headers exist that match the named header (e.g. if there are several
+ :mailheader:`Cc` headers), all are parsed for addresses. Any continuation lines
+ the named headers contain are also parsed.
+
+
+.. method:: Message.getdate(name)
+
+ Retrieve a header using :meth:`getheader` and parse it into a 9-tuple compatible
+ with :func:`time.mktime`; note that fields 6, 7, and 8 are not usable. If
+ there is no header matching *name*, or it is unparsable, return ``None``.
+
+ Date parsing appears to be a black art, and not all mailers adhere to the
+ standard. While it has been tested and found correct on a large collection of
+ email from many sources, it is still possible that this function may
+ occasionally yield an incorrect result.
+
+
+.. method:: Message.getdate_tz(name)
+
+ Retrieve a header using :meth:`getheader` and parse it into a 10-tuple; the
+ first 9 elements will make a tuple compatible with :func:`time.mktime`, and the
+ 10th is a number giving the offset of the date's timezone from UTC. Note that
+ fields 6, 7, and 8 are not usable. Similarly to :meth:`getdate`, if there is
+ no header matching *name*, or it is unparsable, return ``None``.
+
+:class:`Message` instances also support a limited mapping interface. In
+particular: ``m[name]`` is like ``m.getheader(name)`` but raises :exc:`KeyError`
+if there is no matching header; and ``len(m)``, ``m.get(name[, default])``,
+``m.has_key(name)``, ``m.keys()``, ``m.values()`` ``m.items()``, and
+``m.setdefault(name[, default])`` act as expected, with the one difference
+that :meth:`setdefault` uses an empty string as the default value.
+:class:`Message` instances also support the mapping writable interface ``m[name]
+= value`` and ``del m[name]``. :class:`Message` objects do not support the
+:meth:`clear`, :meth:`copy`, :meth:`popitem`, or :meth:`update` methods of the
+mapping interface. (Support for :meth:`get` and :meth:`setdefault` was only
+added in Python 2.2.)
+
+Finally, :class:`Message` instances have some public instance variables:
+
+
+.. attribute:: Message.headers
+
+ A list containing the entire set of header lines, in the order in which they
+ were read (except that setitem calls may disturb this order). Each line contains
+ a trailing newline. The blank line terminating the headers is not contained in
+ the list.
+
+
+.. attribute:: Message.fp
+
+ The file or file-like object passed at instantiation time. This can be used to
+ read the message content.
+
+
+.. attribute:: Message.unixfrom
+
+ The Unix ``From`` line, if the message had one, or an empty string. This is
+ needed to regenerate the message in some contexts, such as an ``mbox``\ -style
+ mailbox file.
+
+
+.. _addresslist-objects:
+
+AddressList Objects
+-------------------
+
+An :class:`AddressList` instance has the following methods:
+
+
+.. method:: AddressList.__len__()
+
+ Return the number of addresses in the address list.
+
+
+.. method:: AddressList.__str__()
+
+ Return a canonicalized string representation of the address list. Addresses are
+ rendered in "name" <host@domain> form, comma-separated.
+
+
+.. method:: AddressList.__add__(alist)
+
+ Return a new :class:`AddressList` instance that contains all addresses in both
+ :class:`AddressList` operands, with duplicates removed (set union).
+
+
+.. method:: AddressList.__iadd__(alist)
+
+ In-place version of :meth:`__add__`; turns this :class:`AddressList` instance
+ into the union of itself and the right-hand instance, *alist*.
+
+
+.. method:: AddressList.__sub__(alist)
+
+ Return a new :class:`AddressList` instance that contains every address in the
+ left-hand :class:`AddressList` operand that is not present in the right-hand
+ address operand (set difference).
+
+
+.. method:: AddressList.__isub__(alist)
+
+ In-place version of :meth:`__sub__`, removing addresses in this list which are
+ also in *alist*.
+
+Finally, :class:`AddressList` instances have one public instance variable:
+
+
+.. attribute:: AddressList.addresslist
+
+ A list of tuple string pairs, one per address. In each member, the first is the
+ canonicalized name part, the second is the actual route-address (``'@'``\
+ -separated username-host.domain pair).
+
+.. rubric:: Footnotes
+
+.. [#] This module originally conformed to :rfc:`822`, hence the name. Since then,
+ :rfc:`2822` has been released as an update to :rfc:`822`. This module should be
+ considered :rfc:`2822`\ -conformant, especially in cases where the syntax or
+ semantics have changed since :rfc:`822`.
+
diff --git a/Doc/library/rlcompleter.rst b/Doc/library/rlcompleter.rst
new file mode 100644
index 0000000000..b882cb0e9b
--- /dev/null
+++ b/Doc/library/rlcompleter.rst
@@ -0,0 +1,65 @@
+
+:mod:`rlcompleter` --- Completion function for GNU readline
+===========================================================
+
+.. module:: rlcompleter
+ :synopsis: Python identifier completion, suitable for the GNU readline library.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`rlcompleter` module defines a completion function suitable for the
+:mod:`readline` module by completing valid Python identifiers and keywords.
+
+When this module is imported on a Unix platform with the :mod:`readline` module
+available, an instance of the :class:`Completer` class is automatically created
+and its :meth:`complete` method is set as the :mod:`readline` completer.
+
+Example::
+
+ >>> import rlcompleter
+ >>> import readline
+ >>> readline.parse_and_bind("tab: complete")
+ >>> readline. <TAB PRESSED>
+ readline.__doc__ readline.get_line_buffer readline.read_init_file
+ readline.__file__ readline.insert_text readline.set_completer
+ readline.__name__ readline.parse_and_bind
+ >>> readline.
+
+The :mod:`rlcompleter` module is designed for use with Python's interactive
+mode. A user can add the following lines to his or her initialization file
+(identified by the :envvar:`PYTHONSTARTUP` environment variable) to get
+automatic :kbd:`Tab` completion::
+
+ try:
+ import readline
+ except ImportError:
+ print "Module readline not available."
+ else:
+ import rlcompleter
+ readline.parse_and_bind("tab: complete")
+
+On platforms without :mod:`readline`, the :class:`Completer` class defined by
+this module can still be used for custom purposes.
+
+
+.. _completer-objects:
+
+Completer Objects
+-----------------
+
+Completer objects have the following method:
+
+
+.. method:: Completer.complete(text, state)
+
+ Return the *state*th completion for *text*.
+
+ If called for *text* that doesn't include a period character (``'.'``), it will
+ complete from names currently defined in :mod:`__main__`, :mod:`__builtin__` and
+ keywords (as defined by the :mod:`keyword` module).
+
+ If called for a dotted name, it will try to evaluate anything without obvious
+ side-effects (functions will not be evaluated, but it can generate calls to
+ :meth:`__getattr__`) up to the last part, and find matches for the rest via the
+ :func:`dir` function.
+
diff --git a/Doc/library/robotparser.rst b/Doc/library/robotparser.rst
new file mode 100644
index 0000000000..1a66955f0b
--- /dev/null
+++ b/Doc/library/robotparser.rst
@@ -0,0 +1,71 @@
+
+:mod:`robotparser` --- Parser for robots.txt
+=============================================
+
+.. module:: robotparser
+ :synopsis: Loads a robots.txt file and answers questions about fetchability of other URLs.
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+.. index::
+ single: WWW
+ single: World Wide Web
+ single: URL
+ single: robots.txt
+
+This module provides a single class, :class:`RobotFileParser`, which answers
+questions about whether or not a particular user agent can fetch a URL on the
+Web site that published the :file:`robots.txt` file. For more details on the
+structure of :file:`robots.txt` files, see
+http://www.robotstxt.org/wc/norobots.html.
+
+
+.. class:: RobotFileParser()
+
+ This class provides a set of methods to read, parse and answer questions about a
+ single :file:`robots.txt` file.
+
+
+ .. method:: RobotFileParser.set_url(url)
+
+ Sets the URL referring to a :file:`robots.txt` file.
+
+
+ .. method:: RobotFileParser.read()
+
+ Reads the :file:`robots.txt` URL and feeds it to the parser.
+
+
+ .. method:: RobotFileParser.parse(lines)
+
+ Parses the lines argument.
+
+
+ .. method:: RobotFileParser.can_fetch(useragent, url)
+
+ Returns ``True`` if the *useragent* is allowed to fetch the *url* according to
+ the rules contained in the parsed :file:`robots.txt` file.
+
+
+ .. method:: RobotFileParser.mtime()
+
+ Returns the time the ``robots.txt`` file was last fetched. This is useful for
+ long-running web spiders that need to check for new ``robots.txt`` files
+ periodically.
+
+
+ .. method:: RobotFileParser.modified()
+
+ Sets the time the ``robots.txt`` file was last fetched to the current time.
+
+The following example demonstrates basic use of the RobotFileParser class. ::
+
+ >>> import robotparser
+ >>> rp = robotparser.RobotFileParser()
+ >>> rp.set_url("http://www.musi-cal.com/robots.txt")
+ >>> rp.read()
+ >>> rp.can_fetch("*", "http://www.musi-cal.com/cgi-bin/search?city=San+Francisco")
+ False
+ >>> rp.can_fetch("*", "http://www.musi-cal.com/")
+ True
+
diff --git a/Doc/library/runpy.rst b/Doc/library/runpy.rst
new file mode 100644
index 0000000000..8846973e30
--- /dev/null
+++ b/Doc/library/runpy.rst
@@ -0,0 +1,71 @@
+:mod:`runpy` --- Locating and executing Python modules
+======================================================
+
+.. module:: runpy
+ :synopsis: Locate and run Python modules without importing them first.
+.. moduleauthor:: Nick Coghlan <ncoghlan@gmail.com>
+
+
+.. versionadded:: 2.5
+
+The :mod:`runpy` module is used to locate and run Python modules without
+importing them first. Its main use is to implement the :option:`-m` command line
+switch that allows scripts to be located using the Python module namespace
+rather than the filesystem.
+
+When executed as a script, the module effectively operates as follows::
+
+ del sys.argv[0] # Remove the runpy module from the arguments
+ run_module(sys.argv[0], run_name="__main__", alter_sys=True)
+
+The :mod:`runpy` module provides a single function:
+
+
+.. function:: run_module(mod_name[, init_globals] [, run_name][, alter_sys])
+
+ Execute the code of the specified module and return the resulting module globals
+ dictionary. The module's code is first located using the standard import
+ mechanism (refer to PEP 302 for details) and then executed in a fresh module
+ namespace.
+
+ The optional dictionary argument *init_globals* may be used to pre-populate the
+ globals dictionary before the code is executed. The supplied dictionary will not
+ be modified. If any of the special global variables below are defined in the
+ supplied dictionary, those definitions are overridden by the ``run_module``
+ function.
+
+ The special global variables ``__name__``, ``__file__``, ``__loader__`` and
+ ``__builtins__`` are set in the globals dictionary before the module code is
+ executed.
+
+ ``__name__`` is set to *run_name* if this optional argument is supplied, and the
+ *mod_name* argument otherwise.
+
+ ``__loader__`` is set to the PEP 302 module loader used to retrieve the code for
+ the module (This loader may be a wrapper around the standard import mechanism).
+
+ ``__file__`` is set to the name provided by the module loader. If the loader
+ does not make filename information available, this variable is set to ``None``.
+
+ ``__builtins__`` is automatically initialised with a reference to the top level
+ namespace of the :mod:`__builtin__` module.
+
+ If the argument *alter_sys* is supplied and evaluates to ``True``, then
+ ``sys.argv[0]`` is updated with the value of ``__file__`` and
+ ``sys.modules[__name__]`` is updated with a new module object for the module
+ being executed. Note that neither ``sys.argv[0]`` nor ``sys.modules[__name__]``
+ are restored to their original values before the function returns -- if client
+ code needs these values preserved, it must either save them explicitly or
+ else avoid enabling the automatic alterations to :mod:`sys`.
+
+ Note that this manipulation of :mod:`sys` is not thread-safe. Other threads may
+ see the partially initialised module, as well as the altered list of arguments.
+ It is recommended that the :mod:`sys` module be left alone when invoking this
+ function from threaded code.
+
+
+.. seealso::
+
+ :pep:`338` - Executing modules as scripts
+ PEP written and implemented by Nick Coghlan.
+
diff --git a/Doc/library/sched.rst b/Doc/library/sched.rst
new file mode 100644
index 0000000000..bf3efbf203
--- /dev/null
+++ b/Doc/library/sched.rst
@@ -0,0 +1,104 @@
+
+:mod:`sched` --- Event scheduler
+================================
+
+.. module:: sched
+ :synopsis: General purpose event scheduler.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+.. % LaTeXed and enhanced from comments in file
+
+.. index:: single: event scheduling
+
+The :mod:`sched` module defines a class which implements a general purpose event
+scheduler:
+
+
+.. class:: scheduler(timefunc, delayfunc)
+
+ The :class:`scheduler` class defines a generic interface to scheduling events.
+ It needs two functions to actually deal with the "outside world" --- *timefunc*
+ should be callable without arguments, and return a number (the "time", in any
+ units whatsoever). The *delayfunc* function should be callable with one
+ argument, compatible with the output of *timefunc*, and should delay that many
+ time units. *delayfunc* will also be called with the argument ``0`` after each
+ event is run to allow other threads an opportunity to run in multi-threaded
+ applications.
+
+Example::
+
+ >>> import sched, time
+ >>> s=sched.scheduler(time.time, time.sleep)
+ >>> def print_time(): print "From print_time", time.time()
+ ...
+ >>> def print_some_times():
+ ... print time.time()
+ ... s.enter(5, 1, print_time, ())
+ ... s.enter(10, 1, print_time, ())
+ ... s.run()
+ ... print time.time()
+ ...
+ >>> print_some_times()
+ 930343690.257
+ From print_time 930343695.274
+ From print_time 930343700.273
+ 930343700.276
+
+
+.. _scheduler-objects:
+
+Scheduler Objects
+-----------------
+
+:class:`scheduler` instances have the following methods:
+
+
+.. method:: scheduler.enterabs(time, priority, action, argument)
+
+ Schedule a new event. The *time* argument should be a numeric type compatible
+ with the return value of the *timefunc* function passed to the constructor.
+ Events scheduled for the same *time* will be executed in the order of their
+ *priority*.
+
+ Executing the event means executing ``action(*argument)``. *argument* must be a
+ sequence holding the parameters for *action*.
+
+ Return value is an event which may be used for later cancellation of the event
+ (see :meth:`cancel`).
+
+
+.. method:: scheduler.enter(delay, priority, action, argument)
+
+ Schedule an event for *delay* more time units. Other then the relative time, the
+ other arguments, the effect and the return value are the same as those for
+ :meth:`enterabs`.
+
+
+.. method:: scheduler.cancel(event)
+
+ Remove the event from the queue. If *event* is not an event currently in the
+ queue, this method will raise a :exc:`RuntimeError`.
+
+
+.. method:: scheduler.empty()
+
+ Return true if the event queue is empty.
+
+
+.. method:: scheduler.run()
+
+ Run all scheduled events. This function will wait (using the :func:`delayfunc`
+ function passed to the constructor) for the next event, then execute it and so
+ on until there are no more scheduled events.
+
+ Either *action* or *delayfunc* can raise an exception. In either case, the
+ scheduler will maintain a consistent state and propagate the exception. If an
+ exception is raised by *action*, the event will not be attempted in future calls
+ to :meth:`run`.
+
+ If a sequence of events takes longer to run than the time available before the
+ next event, the scheduler will simply fall behind. No events will be dropped;
+ the calling code is responsible for canceling events which are no longer
+ pertinent.
+
diff --git a/Doc/library/scrolledtext.rst b/Doc/library/scrolledtext.rst
new file mode 100644
index 0000000000..85456b98f3
--- /dev/null
+++ b/Doc/library/scrolledtext.rst
@@ -0,0 +1,32 @@
+:mod:`ScrolledText` --- Scrolled Text Widget
+============================================
+
+.. module:: ScrolledText
+ :platform: Tk
+ :synopsis: Text widget with a vertical scroll bar.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`ScrolledText` module provides a class of the same name which
+implements a basic text widget which has a vertical scroll bar configured to do
+the "right thing." Using the :class:`ScrolledText` class is a lot easier than
+setting up a text widget and scroll bar directly. The constructor is the same
+as that of the :class:`Tkinter.Text` class.
+
+The text widget and scrollbar are packed together in a :class:`Frame`, and the
+methods of the :class:`Grid` and :class:`Pack` geometry managers are acquired
+from the :class:`Frame` object. This allows the :class:`ScrolledText` widget to
+be used directly to achieve most normal geometry management behavior.
+
+Should more specific control be necessary, the following attributes are
+available:
+
+
+.. attribute:: ScrolledText.frame
+
+ The frame which surrounds the text and scroll bar widgets.
+
+
+.. attribute:: ScrolledText.vbar
+
+ The scroll bar widget.
diff --git a/Doc/library/select.rst b/Doc/library/select.rst
new file mode 100644
index 0000000000..f68a0da091
--- /dev/null
+++ b/Doc/library/select.rst
@@ -0,0 +1,141 @@
+
+:mod:`select` --- Waiting for I/O completion
+============================================
+
+.. module:: select
+ :synopsis: Wait for I/O completion on multiple streams.
+
+
+This module provides access to the :cfunc:`select` and :cfunc:`poll` functions
+available in most operating systems. Note that on Windows, it only works for
+sockets; on other operating systems, it also works for other file types (in
+particular, on Unix, it works on pipes). It cannot be used on regular files to
+determine whether a file has grown since it was last read.
+
+The module defines the following:
+
+
+.. exception:: error
+
+ The exception raised when an error occurs. The accompanying value is a pair
+ containing the numeric error code from :cdata:`errno` and the corresponding
+ string, as would be printed by the C function :cfunc:`perror`.
+
+
+.. function:: poll()
+
+ (Not supported by all operating systems.) Returns a polling object, which
+ supports registering and unregistering file descriptors, and then polling them
+ for I/O events; see section :ref:`poll-objects` below for the methods supported
+ by polling objects.
+
+
+.. function:: select(iwtd, owtd, ewtd[, timeout])
+
+ This is a straightforward interface to the Unix :cfunc:`select` system call.
+ The first three arguments are sequences of 'waitable objects': either
+ integers representing file descriptors or objects with a parameterless method
+ named :meth:`fileno` returning such an integer. The three sequences of
+ waitable objects are for input, output and 'exceptional conditions',
+ respectively. Empty sequences are allowed, but acceptance of three empty
+ sequences is platform-dependent. (It is known to work on Unix but not on
+ Windows.) The optional *timeout* argument specifies a time-out as a floating
+ point number in seconds. When the *timeout* argument is omitted the function
+ blocks until at least one file descriptor is ready. A time-out value of zero
+ specifies a poll and never blocks.
+
+ The return value is a triple of lists of objects that are ready: subsets of the
+ first three arguments. When the time-out is reached without a file descriptor
+ becoming ready, three empty lists are returned.
+
+ .. index::
+ single: socket() (in module socket)
+ single: popen() (in module os)
+
+ Among the acceptable object types in the sequences are Python file objects (e.g.
+ ``sys.stdin``, or objects returned by :func:`open` or :func:`os.popen`), socket
+ objects returned by :func:`socket.socket`. You may also define a :dfn:`wrapper`
+ class yourself, as long as it has an appropriate :meth:`fileno` method (that
+ really returns a file descriptor, not just a random integer).
+
+ .. %
+
+ .. note::
+
+ .. index:: single: WinSock
+
+ File objects on Windows are not acceptable, but sockets are. On Windows, the
+ underlying :cfunc:`select` function is provided by the WinSock library, and does
+ not handle file descriptors that don't originate from WinSock.
+
+
+.. _poll-objects:
+
+Polling Objects
+---------------
+
+The :cfunc:`poll` system call, supported on most Unix systems, provides better
+scalability for network servers that service many, many clients at the same
+time. :cfunc:`poll` scales better because the system call only requires listing
+the file descriptors of interest, while :cfunc:`select` builds a bitmap, turns
+on bits for the fds of interest, and then afterward the whole bitmap has to be
+linearly scanned again. :cfunc:`select` is O(highest file descriptor), while
+:cfunc:`poll` is O(number of file descriptors).
+
+
+.. method:: poll.register(fd[, eventmask])
+
+ Register a file descriptor with the polling object. Future calls to the
+ :meth:`poll` method will then check whether the file descriptor has any pending
+ I/O events. *fd* can be either an integer, or an object with a :meth:`fileno`
+ method that returns an integer. File objects implement :meth:`fileno`, so they
+ can also be used as the argument.
+
+ *eventmask* is an optional bitmask describing the type of events you want to
+ check for, and can be a combination of the constants :const:`POLLIN`,
+ :const:`POLLPRI`, and :const:`POLLOUT`, described in the table below. If not
+ specified, the default value used will check for all 3 types of events.
+
+ +-------------------+------------------------------------------+
+ | Constant | Meaning |
+ +===================+==========================================+
+ | :const:`POLLIN` | There is data to read |
+ +-------------------+------------------------------------------+
+ | :const:`POLLPRI` | There is urgent data to read |
+ +-------------------+------------------------------------------+
+ | :const:`POLLOUT` | Ready for output: writing will not block |
+ +-------------------+------------------------------------------+
+ | :const:`POLLERR` | Error condition of some sort |
+ +-------------------+------------------------------------------+
+ | :const:`POLLHUP` | Hung up |
+ +-------------------+------------------------------------------+
+ | :const:`POLLNVAL` | Invalid request: descriptor not open |
+ +-------------------+------------------------------------------+
+
+ Registering a file descriptor that's already registered is not an error, and has
+ the same effect as registering the descriptor exactly once.
+
+
+.. method:: poll.unregister(fd)
+
+ Remove a file descriptor being tracked by a polling object. Just like the
+ :meth:`register` method, *fd* can be an integer or an object with a
+ :meth:`fileno` method that returns an integer.
+
+ Attempting to remove a file descriptor that was never registered causes a
+ :exc:`KeyError` exception to be raised.
+
+
+.. method:: poll.poll([timeout])
+
+ Polls the set of registered file descriptors, and returns a possibly-empty list
+ containing ``(fd, event)`` 2-tuples for the descriptors that have events or
+ errors to report. *fd* is the file descriptor, and *event* is a bitmask with
+ bits set for the reported events for that descriptor --- :const:`POLLIN` for
+ waiting input, :const:`POLLOUT` to indicate that the descriptor can be written
+ to, and so forth. An empty list indicates that the call timed out and no file
+ descriptors had any events to report. If *timeout* is given, it specifies the
+ length of time in milliseconds which the system will wait for events before
+ returning. If *timeout* is omitted, negative, or :const:`None`, the call will
+ block until there is an event for this poll object.
+
diff --git a/Doc/library/sgmllib.rst b/Doc/library/sgmllib.rst
new file mode 100644
index 0000000000..c0ef1a2953
--- /dev/null
+++ b/Doc/library/sgmllib.rst
@@ -0,0 +1,270 @@
+
+:mod:`sgmllib` --- Simple SGML parser
+=====================================
+
+.. module:: sgmllib
+ :synopsis: Only as much of an SGML parser as needed to parse HTML.
+
+
+.. index:: single: SGML
+
+This module defines a class :class:`SGMLParser` which serves as the basis for
+parsing text files formatted in SGML (Standard Generalized Mark-up Language).
+In fact, it does not provide a full SGML parser --- it only parses SGML insofar
+as it is used by HTML, and the module only exists as a base for the
+:mod:`htmllib` module. Another HTML parser which supports XHTML and offers a
+somewhat different interface is available in the :mod:`HTMLParser` module.
+
+
+.. class:: SGMLParser()
+
+ The :class:`SGMLParser` class is instantiated without arguments. The parser is
+ hardcoded to recognize the following constructs:
+
+ * Opening and closing tags of the form ``<tag attr="value" ...>`` and
+ ``</tag>``, respectively.
+
+ * Numeric character references of the form ``&#name;``.
+
+ * Entity references of the form ``&name;``.
+
+ * SGML comments of the form ``<!--text-->``. Note that spaces, tabs, and
+ newlines are allowed between the trailing ``>`` and the immediately preceding
+ ``--``.
+
+A single exception is defined as well:
+
+
+.. exception:: SGMLParseError
+
+ Exception raised by the :class:`SGMLParser` class when it encounters an error
+ while parsing.
+
+ .. versionadded:: 2.1
+
+:class:`SGMLParser` instances have the following methods:
+
+
+.. method:: SGMLParser.reset()
+
+ Reset the instance. Loses all unprocessed data. This is called implicitly at
+ instantiation time.
+
+
+.. method:: SGMLParser.setnomoretags()
+
+ Stop processing tags. Treat all following input as literal input (CDATA).
+ (This is only provided so the HTML tag ``<PLAINTEXT>`` can be implemented.)
+
+
+.. method:: SGMLParser.setliteral()
+
+ Enter literal mode (CDATA mode).
+
+
+.. method:: SGMLParser.feed(data)
+
+ Feed some text to the parser. It is processed insofar as it consists of
+ complete elements; incomplete data is buffered until more data is fed or
+ :meth:`close` is called.
+
+
+.. method:: SGMLParser.close()
+
+ Force processing of all buffered data as if it were followed by an end-of-file
+ mark. This method may be redefined by a derived class to define additional
+ processing at the end of the input, but the redefined version should always call
+ :meth:`close`.
+
+
+.. method:: SGMLParser.get_starttag_text()
+
+ Return the text of the most recently opened start tag. This should not normally
+ be needed for structured processing, but may be useful in dealing with HTML "as
+ deployed" or for re-generating input with minimal changes (whitespace between
+ attributes can be preserved, etc.).
+
+
+.. method:: SGMLParser.handle_starttag(tag, method, attributes)
+
+ This method is called to handle start tags for which either a :meth:`start_tag`
+ or :meth:`do_tag` method has been defined. The *tag* argument is the name of
+ the tag converted to lower case, and the *method* argument is the bound method
+ which should be used to support semantic interpretation of the start tag. The
+ *attributes* argument is a list of ``(name, value)`` pairs containing the
+ attributes found inside the tag's ``<>`` brackets.
+
+ The *name* has been translated to lower case. Double quotes and backslashes in
+ the *value* have been interpreted, as well as known character references and
+ known entity references terminated by a semicolon (normally, entity references
+ can be terminated by any non-alphanumerical character, but this would break the
+ very common case of ``<A HREF="url?spam=1&eggs=2">`` when ``eggs`` is a valid
+ entity name).
+
+ For instance, for the tag ``<A HREF="http://www.cwi.nl/">``, this method would
+ be called as ``unknown_starttag('a', [('href', 'http://www.cwi.nl/')])``. The
+ base implementation simply calls *method* with *attributes* as the only
+ argument.
+
+ .. versionadded:: 2.5
+ Handling of entity and character references within attribute values.
+
+
+.. method:: SGMLParser.handle_endtag(tag, method)
+
+ This method is called to handle endtags for which an :meth:`end_tag` method has
+ been defined. The *tag* argument is the name of the tag converted to lower
+ case, and the *method* argument is the bound method which should be used to
+ support semantic interpretation of the end tag. If no :meth:`end_tag` method is
+ defined for the closing element, this handler is not called. The base
+ implementation simply calls *method*.
+
+
+.. method:: SGMLParser.handle_data(data)
+
+ This method is called to process arbitrary data. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+
+.. method:: SGMLParser.handle_charref(ref)
+
+ This method is called to process a character reference of the form ``&#ref;``.
+ The base implementation uses :meth:`convert_charref` to convert the reference to
+ a string. If that method returns a string, it is passed to :meth:`handle_data`,
+ otherwise ``unknown_charref(ref)`` is called to handle the error.
+
+ .. versionchanged:: 2.5
+ Use :meth:`convert_charref` instead of hard-coding the conversion.
+
+
+.. method:: SGMLParser.convert_charref(ref)
+
+ Convert a character reference to a string, or ``None``. *ref* is the reference
+ passed in as a string. In the base implementation, *ref* must be a decimal
+ number in the range 0-255. It converts the code point found using the
+ :meth:`convert_codepoint` method. If *ref* is invalid or out of range, this
+ method returns ``None``. This method is called by the default
+ :meth:`handle_charref` implementation and by the attribute value parser.
+
+ .. versionadded:: 2.5
+
+
+.. method:: SGMLParser.convert_codepoint(codepoint)
+
+ Convert a codepoint to a :class:`str` value. Encodings can be handled here if
+ appropriate, though the rest of :mod:`sgmllib` is oblivious on this matter.
+
+ .. versionadded:: 2.5
+
+
+.. method:: SGMLParser.handle_entityref(ref)
+
+ This method is called to process a general entity reference of the form
+ ``&ref;`` where *ref* is an general entity reference. It converts *ref* by
+ passing it to :meth:`convert_entityref`. If a translation is returned, it calls
+ the method :meth:`handle_data` with the translation; otherwise, it calls the
+ method ``unknown_entityref(ref)``. The default :attr:`entitydefs` defines
+ translations for ``&amp;``, ``&apos``, ``&gt;``, ``&lt;``, and ``&quot;``.
+
+ .. versionchanged:: 2.5
+ Use :meth:`convert_entityref` instead of hard-coding the conversion.
+
+
+.. method:: SGMLParser.convert_entityref(ref)
+
+ Convert a named entity reference to a :class:`str` value, or ``None``. The
+ resulting value will not be parsed. *ref* will be only the name of the entity.
+ The default implementation looks for *ref* in the instance (or class) variable
+ :attr:`entitydefs` which should be a mapping from entity names to corresponding
+ translations. If no translation is available for *ref*, this method returns
+ ``None``. This method is called by the default :meth:`handle_entityref`
+ implementation and by the attribute value parser.
+
+ .. versionadded:: 2.5
+
+
+.. method:: SGMLParser.handle_comment(comment)
+
+ This method is called when a comment is encountered. The *comment* argument is
+ a string containing the text between the ``<!--`` and ``-->`` delimiters, but
+ not the delimiters themselves. For example, the comment ``<!--text-->`` will
+ cause this method to be called with the argument ``'text'``. The default method
+ does nothing.
+
+
+.. method:: SGMLParser.handle_decl(data)
+
+ Method called when an SGML declaration is read by the parser. In practice, the
+ ``DOCTYPE`` declaration is the only thing observed in HTML, but the parser does
+ not discriminate among different (or broken) declarations. Internal subsets in
+ a ``DOCTYPE`` declaration are not supported. The *data* parameter will be the
+ entire contents of the declaration inside the ``<!``...\ ``>`` markup. The
+ default implementation does nothing.
+
+
+.. method:: SGMLParser.report_unbalanced(tag)
+
+ This method is called when an end tag is found which does not correspond to any
+ open element.
+
+
+.. method:: SGMLParser.unknown_starttag(tag, attributes)
+
+ This method is called to process an unknown start tag. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+
+.. method:: SGMLParser.unknown_endtag(tag)
+
+ This method is called to process an unknown end tag. It is intended to be
+ overridden by a derived class; the base class implementation does nothing.
+
+
+.. method:: SGMLParser.unknown_charref(ref)
+
+ This method is called to process unresolvable numeric character references.
+ Refer to :meth:`handle_charref` to determine what is handled by default. It is
+ intended to be overridden by a derived class; the base class implementation does
+ nothing.
+
+
+.. method:: SGMLParser.unknown_entityref(ref)
+
+ This method is called to process an unknown entity reference. It is intended to
+ be overridden by a derived class; the base class implementation does nothing.
+
+Apart from overriding or extending the methods listed above, derived classes may
+also define methods of the following form to define processing of specific tags.
+Tag names in the input stream are case independent; the *tag* occurring in
+method names must be in lower case:
+
+
+.. method:: SGMLParser.start_tag(attributes)
+ :noindex:
+
+ This method is called to process an opening tag *tag*. It has preference over
+ :meth:`do_tag`. The *attributes* argument has the same meaning as described for
+ :meth:`handle_starttag` above.
+
+
+.. method:: SGMLParser.do_tag(attributes)
+ :noindex:
+
+ This method is called to process an opening tag *tag* for which no
+ :meth:`start_tag` method is defined. The *attributes* argument has the same
+ meaning as described for :meth:`handle_starttag` above.
+
+
+.. method:: SGMLParser.end_tag()
+ :noindex:
+
+ This method is called to process a closing tag *tag*.
+
+Note that the parser maintains a stack of open elements for which no end tag has
+been found yet. Only tags processed by :meth:`start_tag` are pushed on this
+stack. Definition of an :meth:`end_tag` method is optional for these tags. For
+tags processed by :meth:`do_tag` or by :meth:`unknown_tag`, no :meth:`end_tag`
+method must be defined; if defined, it will not be used. If both
+:meth:`start_tag` and :meth:`do_tag` methods exist for a tag, the
+:meth:`start_tag` method takes precedence.
+
diff --git a/Doc/library/shelve.rst b/Doc/library/shelve.rst
new file mode 100644
index 0000000000..1776b7d5cc
--- /dev/null
+++ b/Doc/library/shelve.rst
@@ -0,0 +1,185 @@
+
+:mod:`shelve` --- Python object persistence
+===========================================
+
+.. module:: shelve
+ :synopsis: Python object persistence.
+
+
+.. index:: module: pickle
+
+A "shelf" is a persistent, dictionary-like object. The difference with "dbm"
+databases is that the values (not the keys!) in a shelf can be essentially
+arbitrary Python objects --- anything that the :mod:`pickle` module can handle.
+This includes most class instances, recursive data types, and objects containing
+lots of shared sub-objects. The keys are ordinary strings.
+
+
+.. function:: open(filename[, flag='c'[, protocol=None[, writeback=False]]])
+
+ Open a persistent dictionary. The filename specified is the base filename for
+ the underlying database. As a side-effect, an extension may be added to the
+ filename and more than one file may be created. By default, the underlying
+ database file is opened for reading and writing. The optional *flag* parameter
+ has the same interpretation as the *flag* parameter of :func:`anydbm.open`.
+
+ By default, version 0 pickles are used to serialize values. The version of the
+ pickle protocol can be specified with the *protocol* parameter.
+
+ .. versionchanged:: 2.3
+ The *protocol* parameter was added.
+
+ By default, mutations to persistent-dictionary mutable entries are not
+ automatically written back. If the optional *writeback* parameter is set to
+ *True*, all entries accessed are cached in memory, and written back at close
+ time; this can make it handier to mutate mutable entries in the persistent
+ dictionary, but, if many entries are accessed, it can consume vast amounts of
+ memory for the cache, and it can make the close operation very slow since all
+ accessed entries are written back (there is no way to determine which accessed
+ entries are mutable, nor which ones were actually mutated).
+
+Shelve objects support all methods supported by dictionaries. This eases the
+transition from dictionary based scripts to those requiring persistent storage.
+
+One additional method is supported:
+
+
+.. method:: Shelf.sync()
+
+ Write back all entries in the cache if the shelf was opened with *writeback* set
+ to *True*. Also empty the cache and synchronize the persistent dictionary on
+ disk, if feasible. This is called automatically when the shelf is closed with
+ :meth:`close`.
+
+
+Restrictions
+------------
+
+ .. index::
+ module: dbm
+ module: gdbm
+ module: bsddb
+
+* The choice of which database package will be used (such as :mod:`dbm`,
+ :mod:`gdbm` or :mod:`bsddb`) depends on which interface is available. Therefore
+ it is not safe to open the database directly using :mod:`dbm`. The database is
+ also (unfortunately) subject to the limitations of :mod:`dbm`, if it is used ---
+ this means that (the pickled representation of) the objects stored in the
+ database should be fairly small, and in rare cases key collisions may cause the
+ database to refuse updates.
+
+* Depending on the implementation, closing a persistent dictionary may or may
+ not be necessary to flush changes to disk. The :meth:`__del__` method of the
+ :class:`Shelf` class calls the :meth:`close` method, so the programmer generally
+ need not do this explicitly.
+
+* The :mod:`shelve` module does not support *concurrent* read/write access to
+ shelved objects. (Multiple simultaneous read accesses are safe.) When a
+ program has a shelf open for writing, no other program should have it open for
+ reading or writing. Unix file locking can be used to solve this, but this
+ differs across Unix versions and requires knowledge about the database
+ implementation used.
+
+
+.. class:: Shelf(dict[, protocol=None[, writeback=False]])
+
+ A subclass of :class:`UserDict.DictMixin` which stores pickled values in the
+ *dict* object.
+
+ By default, version 0 pickles are used to serialize values. The version of the
+ pickle protocol can be specified with the *protocol* parameter. See the
+ :mod:`pickle` documentation for a discussion of the pickle protocols.
+
+ .. versionchanged:: 2.3
+ The *protocol* parameter was added.
+
+ If the *writeback* parameter is ``True``, the object will hold a cache of all
+ entries accessed and write them back to the *dict* at sync and close times.
+ This allows natural operations on mutable entries, but can consume much more
+ memory and make sync and close take a long time.
+
+
+.. class:: BsdDbShelf(dict[, protocol=None[, writeback=False]])
+
+ A subclass of :class:`Shelf` which exposes :meth:`first`, :meth:`next`,
+ :meth:`previous`, :meth:`last` and :meth:`set_location` which are available in
+ the :mod:`bsddb` module but not in other database modules. The *dict* object
+ passed to the constructor must support those methods. This is generally
+ accomplished by calling one of :func:`bsddb.hashopen`, :func:`bsddb.btopen` or
+ :func:`bsddb.rnopen`. The optional *protocol* and *writeback* parameters have
+ the same interpretation as for the :class:`Shelf` class.
+
+
+.. class:: DbfilenameShelf(filename[, flag='c'[, protocol=None[, writeback=False]]])
+
+ A subclass of :class:`Shelf` which accepts a *filename* instead of a dict-like
+ object. The underlying file will be opened using :func:`anydbm.open`. By
+ default, the file will be created and opened for both read and write. The
+ optional *flag* parameter has the same interpretation as for the :func:`open`
+ function. The optional *protocol* and *writeback* parameters have the same
+ interpretation as for the :class:`Shelf` class.
+
+
+Example
+-------
+
+To summarize the interface (``key`` is a string, ``data`` is an arbitrary
+object)::
+
+ import shelve
+
+ d = shelve.open(filename) # open -- file may get suffix added by low-level
+ # library
+
+ d[key] = data # store data at key (overwrites old data if
+ # using an existing key)
+ data = d[key] # retrieve a COPY of data at key (raise KeyError if no
+ # such key)
+ del d[key] # delete data stored at key (raises KeyError
+ # if no such key)
+ flag = d.has_key(key) # true if the key exists
+ klist = d.keys() # a list of all existing keys (slow!)
+
+ # as d was opened WITHOUT writeback=True, beware:
+ d['xx'] = range(4) # this works as expected, but...
+ d['xx'].append(5) # *this doesn't!* -- d['xx'] is STILL range(4)!!!
+
+ # having opened d without writeback=True, you need to code carefully:
+ temp = d['xx'] # extracts the copy
+ temp.append(5) # mutates the copy
+ d['xx'] = temp # stores the copy right back, to persist it
+
+ # or, d=shelve.open(filename,writeback=True) would let you just code
+ # d['xx'].append(5) and have it work as expected, BUT it would also
+ # consume more memory and make the d.close() operation slower.
+
+ d.close() # close it
+
+
+.. seealso::
+
+ Module :mod:`anydbm`
+ Generic interface to ``dbm``\ -style databases.
+
+ Module :mod:`bsddb`
+ BSD ``db`` database interface.
+
+ Module :mod:`dbhash`
+ Thin layer around the :mod:`bsddb` which provides an :func:`open` function like
+ the other database modules.
+
+ Module :mod:`dbm`
+ Standard Unix database interface.
+
+ Module :mod:`dumbdbm`
+ Portable implementation of the ``dbm`` interface.
+
+ Module :mod:`gdbm`
+ GNU database interface, based on the ``dbm`` interface.
+
+ Module :mod:`pickle`
+ Object serialization used by :mod:`shelve`.
+
+ Module :mod:`cPickle`
+ High-performance version of :mod:`pickle`.
+
diff --git a/Doc/library/shlex.rst b/Doc/library/shlex.rst
new file mode 100644
index 0000000000..0ae77c173a
--- /dev/null
+++ b/Doc/library/shlex.rst
@@ -0,0 +1,307 @@
+
+:mod:`shlex` --- Simple lexical analysis
+========================================
+
+.. module:: shlex
+ :synopsis: Simple lexical analysis for Unix shell-like languages.
+.. moduleauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+.. moduleauthor:: Gustavo Niemeyer <niemeyer@conectiva.com>
+.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+.. sectionauthor:: Gustavo Niemeyer <niemeyer@conectiva.com>
+
+
+.. versionadded:: 1.5.2
+
+The :class:`shlex` class makes it easy to write lexical analyzers for simple
+syntaxes resembling that of the Unix shell. This will often be useful for
+writing minilanguages, (for example, in run control files for Python
+applications) or for parsing quoted strings.
+
+.. note::
+
+ The :mod:`shlex` module currently does not support Unicode input.
+
+The :mod:`shlex` module defines the following functions:
+
+
+.. function:: split(s[, comments[, posix]])
+
+ Split the string *s* using shell-like syntax. If *comments* is :const:`False`
+ (the default), the parsing of comments in the given string will be disabled
+ (setting the :attr:`commenters` member of the :class:`shlex` instance to the
+ empty string). This function operates in POSIX mode by default, but uses
+ non-POSIX mode if the *posix* argument is false.
+
+ .. versionadded:: 2.3
+
+ .. versionchanged:: 2.6
+ Added the *posix* parameter.
+
+ .. note::
+
+ Since the :func:`split` function instantiates a :class:`shlex` instance, passing
+ ``None`` for *s* will read the string to split from standard input.
+
+The :mod:`shlex` module defines the following class:
+
+
+.. class:: shlex([instream[, infile[, posix]]])
+
+ A :class:`shlex` instance or subclass instance is a lexical analyzer object.
+ The initialization argument, if present, specifies where to read characters
+ from. It must be a file-/stream-like object with :meth:`read` and
+ :meth:`readline` methods, or a string (strings are accepted since Python 2.3).
+ If no argument is given, input will be taken from ``sys.stdin``. The second
+ optional argument is a filename string, which sets the initial value of the
+ :attr:`infile` member. If the *instream* argument is omitted or equal to
+ ``sys.stdin``, this second argument defaults to "stdin". The *posix* argument
+ was introduced in Python 2.3, and defines the operational mode. When *posix* is
+ not true (default), the :class:`shlex` instance will operate in compatibility
+ mode. When operating in POSIX mode, :class:`shlex` will try to be as close as
+ possible to the POSIX shell parsing rules.
+
+
+.. seealso::
+
+ Module :mod:`ConfigParser`
+ Parser for configuration files similar to the Windows :file:`.ini` files.
+
+
+.. _shlex-objects:
+
+shlex Objects
+-------------
+
+A :class:`shlex` instance has the following methods:
+
+
+.. method:: shlex.get_token()
+
+ Return a token. If tokens have been stacked using :meth:`push_token`, pop a
+ token off the stack. Otherwise, read one from the input stream. If reading
+ encounters an immediate end-of-file, :attr:`self.eof` is returned (the empty
+ string (``''``) in non-POSIX mode, and ``None`` in POSIX mode).
+
+
+.. method:: shlex.push_token(str)
+
+ Push the argument onto the token stack.
+
+
+.. method:: shlex.read_token()
+
+ Read a raw token. Ignore the pushback stack, and do not interpret source
+ requests. (This is not ordinarily a useful entry point, and is documented here
+ only for the sake of completeness.)
+
+
+.. method:: shlex.sourcehook(filename)
+
+ When :class:`shlex` detects a source request (see :attr:`source` below) this
+ method is given the following token as argument, and expected to return a tuple
+ consisting of a filename and an open file-like object.
+
+ Normally, this method first strips any quotes off the argument. If the result
+ is an absolute pathname, or there was no previous source request in effect, or
+ the previous source was a stream (such as ``sys.stdin``), the result is left
+ alone. Otherwise, if the result is a relative pathname, the directory part of
+ the name of the file immediately before it on the source inclusion stack is
+ prepended (this behavior is like the way the C preprocessor handles ``#include
+ "file.h"``).
+
+ The result of the manipulations is treated as a filename, and returned as the
+ first component of the tuple, with :func:`open` called on it to yield the second
+ component. (Note: this is the reverse of the order of arguments in instance
+ initialization!)
+
+ This hook is exposed so that you can use it to implement directory search paths,
+ addition of file extensions, and other namespace hacks. There is no
+ corresponding 'close' hook, but a shlex instance will call the :meth:`close`
+ method of the sourced input stream when it returns EOF.
+
+ For more explicit control of source stacking, use the :meth:`push_source` and
+ :meth:`pop_source` methods.
+
+
+.. method:: shlex.push_source(stream[, filename])
+
+ Push an input source stream onto the input stack. If the filename argument is
+ specified it will later be available for use in error messages. This is the
+ same method used internally by the :meth:`sourcehook` method.
+
+ .. versionadded:: 2.1
+
+
+.. method:: shlex.pop_source()
+
+ Pop the last-pushed input source from the input stack. This is the same method
+ used internally when the lexer reaches EOF on a stacked input stream.
+
+ .. versionadded:: 2.1
+
+
+.. method:: shlex.error_leader([file[, line]])
+
+ This method generates an error message leader in the format of a Unix C compiler
+ error label; the format is ``'"%s", line %d: '``, where the ``%s`` is replaced
+ with the name of the current source file and the ``%d`` with the current input
+ line number (the optional arguments can be used to override these).
+
+ This convenience is provided to encourage :mod:`shlex` users to generate error
+ messages in the standard, parseable format understood by Emacs and other Unix
+ tools.
+
+Instances of :class:`shlex` subclasses have some public instance variables which
+either control lexical analysis or can be used for debugging:
+
+
+.. attribute:: shlex.commenters
+
+ The string of characters that are recognized as comment beginners. All
+ characters from the comment beginner to end of line are ignored. Includes just
+ ``'#'`` by default.
+
+
+.. attribute:: shlex.wordchars
+
+ The string of characters that will accumulate into multi-character tokens. By
+ default, includes all ASCII alphanumerics and underscore.
+
+
+.. attribute:: shlex.whitespace
+
+ Characters that will be considered whitespace and skipped. Whitespace bounds
+ tokens. By default, includes space, tab, linefeed and carriage-return.
+
+
+.. attribute:: shlex.escape
+
+ Characters that will be considered as escape. This will be only used in POSIX
+ mode, and includes just ``'\'`` by default.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: shlex.quotes
+
+ Characters that will be considered string quotes. The token accumulates until
+ the same quote is encountered again (thus, different quote types protect each
+ other as in the shell.) By default, includes ASCII single and double quotes.
+
+
+.. attribute:: shlex.escapedquotes
+
+ Characters in :attr:`quotes` that will interpret escape characters defined in
+ :attr:`escape`. This is only used in POSIX mode, and includes just ``'"'`` by
+ default.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: shlex.whitespace_split
+
+ If ``True``, tokens will only be split in whitespaces. This is useful, for
+ example, for parsing command lines with :class:`shlex`, getting tokens in a
+ similar way to shell arguments.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: shlex.infile
+
+ The name of the current input file, as initially set at class instantiation time
+ or stacked by later source requests. It may be useful to examine this when
+ constructing error messages.
+
+
+.. attribute:: shlex.instream
+
+ The input stream from which this :class:`shlex` instance is reading characters.
+
+
+.. attribute:: shlex.source
+
+ This member is ``None`` by default. If you assign a string to it, that string
+ will be recognized as a lexical-level inclusion request similar to the
+ ``source`` keyword in various shells. That is, the immediately following token
+ will opened as a filename and input taken from that stream until EOF, at which
+ point the :meth:`close` method of that stream will be called and the input
+ source will again become the original input stream. Source requests may be
+ stacked any number of levels deep.
+
+
+.. attribute:: shlex.debug
+
+ If this member is numeric and ``1`` or more, a :class:`shlex` instance will
+ print verbose progress output on its behavior. If you need to use this, you can
+ read the module source code to learn the details.
+
+
+.. attribute:: shlex.lineno
+
+ Source line number (count of newlines seen so far plus one).
+
+
+.. attribute:: shlex.token
+
+ The token buffer. It may be useful to examine this when catching exceptions.
+
+
+.. attribute:: shlex.eof
+
+ Token used to determine end of file. This will be set to the empty string
+ (``''``), in non-POSIX mode, and to ``None`` in POSIX mode.
+
+ .. versionadded:: 2.3
+
+
+.. _shlex-parsing-rules:
+
+Parsing Rules
+-------------
+
+When operating in non-POSIX mode, :class:`shlex` will try to obey to the
+following rules.
+
+* Quote characters are not recognized within words (``Do"Not"Separate`` is
+ parsed as the single word ``Do"Not"Separate``);
+
+* Escape characters are not recognized;
+
+* Enclosing characters in quotes preserve the literal value of all characters
+ within the quotes;
+
+* Closing quotes separate words (``"Do"Separate`` is parsed as ``"Do"`` and
+ ``Separate``);
+
+* If :attr:`whitespace_split` is ``False``, any character not declared to be a
+ word character, whitespace, or a quote will be returned as a single-character
+ token. If it is ``True``, :class:`shlex` will only split words in whitespaces;
+
+* EOF is signaled with an empty string (``''``);
+
+* It's not possible to parse empty strings, even if quoted.
+
+When operating in POSIX mode, :class:`shlex` will try to obey to the following
+parsing rules.
+
+* Quotes are stripped out, and do not separate words (``"Do"Not"Separate"`` is
+ parsed as the single word ``DoNotSeparate``);
+
+* Non-quoted escape characters (e.g. ``'\'``) preserve the literal value of the
+ next character that follows;
+
+* Enclosing characters in quotes which are not part of :attr:`escapedquotes`
+ (e.g. ``"'"``) preserve the literal value of all characters within the quotes;
+
+* Enclosing characters in quotes which are part of :attr:`escapedquotes` (e.g.
+ ``'"'``) preserves the literal value of all characters within the quotes, with
+ the exception of the characters mentioned in :attr:`escape`. The escape
+ characters retain its special meaning only when followed by the quote in use, or
+ the escape character itself. Otherwise the escape character will be considered a
+ normal character.
+
+* EOF is signaled with a :const:`None` value;
+
+* Quoted empty strings (``''``) are allowed;
+
diff --git a/Doc/library/shutil.rst b/Doc/library/shutil.rst
new file mode 100644
index 0000000000..ef0758dc80
--- /dev/null
+++ b/Doc/library/shutil.rst
@@ -0,0 +1,171 @@
+
+:mod:`shutil` --- High-level file operations
+============================================
+
+.. module:: shutil
+ :synopsis: High-level file operations, including copying.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. % partly based on the docstrings
+
+.. index::
+ single: file; copying
+ single: copying files
+
+The :mod:`shutil` module offers a number of high-level operations on files and
+collections of files. In particular, functions are provided which support file
+copying and removal.
+
+**Caveat:** On MacOS, the resource fork and other metadata are not used. For
+file copies, this means that resources will be lost and file type and creator
+codes will not be correct.
+
+
+.. function:: copyfile(src, dst)
+
+ Copy the contents of the file named *src* to a file named *dst*. The
+ destination location must be writable; otherwise, an :exc:`IOError` exception
+ will be raised. If *dst* already exists, it will be replaced. Special files
+ such as character or block devices and pipes cannot be copied with this
+ function. *src* and *dst* are path names given as strings.
+
+
+.. function:: copyfileobj(fsrc, fdst[, length])
+
+ Copy the contents of the file-like object *fsrc* to the file-like object *fdst*.
+ The integer *length*, if given, is the buffer size. In particular, a negative
+ *length* value means to copy the data without looping over the source data in
+ chunks; by default the data is read in chunks to avoid uncontrolled memory
+ consumption. Note that if the current file position of the *fsrc* object is not
+ 0, only the contents from the current file position to the end of the file will
+ be copied.
+
+
+.. function:: copymode(src, dst)
+
+ Copy the permission bits from *src* to *dst*. The file contents, owner, and
+ group are unaffected. *src* and *dst* are path names given as strings.
+
+
+.. function:: copystat(src, dst)
+
+ Copy the permission bits, last access time, last modification time, and flags
+ from *src* to *dst*. The file contents, owner, and group are unaffected. *src*
+ and *dst* are path names given as strings.
+
+
+.. function:: copy(src, dst)
+
+ Copy the file *src* to the file or directory *dst*. If *dst* is a directory, a
+ file with the same basename as *src* is created (or overwritten) in the
+ directory specified. Permission bits are copied. *src* and *dst* are path
+ names given as strings.
+
+
+.. function:: copy2(src, dst)
+
+ Similar to :func:`copy`, but last access time and last modification time are
+ copied as well. This is similar to the Unix command :program:`cp -p`.
+
+
+.. function:: copytree(src, dst[, symlinks])
+
+ Recursively copy an entire directory tree rooted at *src*. The destination
+ directory, named by *dst*, must not already exist; it will be created as well as
+ missing parent directories. Permissions and times of directories are copied with
+ :func:`copystat`, individual files are copied using :func:`copy2`. If
+ *symlinks* is true, symbolic links in the source tree are represented as
+ symbolic links in the new tree; if false or omitted, the contents of the linked
+ files are copied to the new tree. If exception(s) occur, an :exc:`Error` is
+ raised with a list of reasons.
+
+ The source code for this should be considered an example rather than a tool.
+
+ .. versionchanged:: 2.3
+ :exc:`Error` is raised if any exceptions occur during copying, rather than
+ printing a message.
+
+ .. versionchanged:: 2.5
+ Create intermediate directories needed to create *dst*, rather than raising an
+ error. Copy permissions and times of directories using :func:`copystat`.
+
+
+.. function:: rmtree(path[, ignore_errors[, onerror]])
+
+ .. index:: single: directory; deleting
+
+ Delete an entire directory tree (*path* must point to a directory). If
+ *ignore_errors* is true, errors resulting from failed removals will be ignored;
+ if false or omitted, such errors are handled by calling a handler specified by
+ *onerror* or, if that is omitted, they raise an exception.
+
+ If *onerror* is provided, it must be a callable that accepts three parameters:
+ *function*, *path*, and *excinfo*. The first parameter, *function*, is the
+ function which raised the exception; it will be :func:`os.listdir`,
+ :func:`os.remove` or :func:`os.rmdir`. The second parameter, *path*, will be
+ the path name passed to *function*. The third parameter, *excinfo*, will be the
+ exception information return by :func:`sys.exc_info`. Exceptions raised by
+ *onerror* will not be caught.
+
+
+.. function:: move(src, dst)
+
+ Recursively move a file or directory to another location.
+
+ If the destination is on our current filesystem, then simply use rename.
+ Otherwise, copy src to the dst and then remove src.
+
+ .. versionadded:: 2.3
+
+
+.. exception:: Error
+
+ This exception collects exceptions that raised during a mult-file operation. For
+ :func:`copytree`, the exception argument is a list of 3-tuples (*srcname*,
+ *dstname*, *exception*).
+
+ .. versionadded:: 2.3
+
+
+.. _shutil-example:
+
+Example
+-------
+
+This example is the implementation of the :func:`copytree` function, described
+above, with the docstring omitted. It demonstrates many of the other functions
+provided by this module. ::
+
+ def copytree(src, dst, symlinks=False):
+ names = os.listdir(src)
+ os.makedirs(dst)
+ errors = []
+ for name in names:
+ srcname = os.path.join(src, name)
+ dstname = os.path.join(dst, name)
+ try:
+ if symlinks and os.path.islink(srcname):
+ linkto = os.readlink(srcname)
+ os.symlink(linkto, dstname)
+ elif os.path.isdir(srcname):
+ copytree(srcname, dstname, symlinks)
+ else:
+ copy2(srcname, dstname)
+ # XXX What about devices, sockets etc.?
+ except (IOError, os.error) as why:
+ errors.append((srcname, dstname, str(why)))
+ # catch the Error from the recursive copytree so that we can
+ # continue with other files
+ except Error as err:
+ errors.extend(err.args[0])
+ try:
+ copystat(src, dst)
+ except WindowsError:
+ # can't copy file access times on Windows
+ pass
+ except OSError as why:
+ errors.extend((src, dst, str(why)))
+ if errors:
+ raise Error, errors
+
diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
new file mode 100644
index 0000000000..54cce533b5
--- /dev/null
+++ b/Doc/library/signal.rst
@@ -0,0 +1,157 @@
+
+:mod:`signal` --- Set handlers for asynchronous events
+======================================================
+
+.. module:: signal
+ :synopsis: Set handlers for asynchronous events.
+
+
+This module provides mechanisms to use signal handlers in Python. Some general
+rules for working with signals and their handlers:
+
+* A handler for a particular signal, once set, remains installed until it is
+ explicitly reset (Python emulates the BSD style interface regardless of the
+ underlying implementation), with the exception of the handler for
+ :const:`SIGCHLD`, which follows the underlying implementation.
+
+* There is no way to "block" signals temporarily from critical sections (since
+ this is not supported by all Unix flavors).
+
+* Although Python signal handlers are called asynchronously as far as the Python
+ user is concerned, they can only occur between the "atomic" instructions of the
+ Python interpreter. This means that signals arriving during long calculations
+ implemented purely in C (such as regular expression matches on large bodies of
+ text) may be delayed for an arbitrary amount of time.
+
+* When a signal arrives during an I/O operation, it is possible that the I/O
+ operation raises an exception after the signal handler returns. This is
+ dependent on the underlying Unix system's semantics regarding interrupted system
+ calls.
+
+* Because the C signal handler always returns, it makes little sense to catch
+ synchronous errors like :const:`SIGFPE` or :const:`SIGSEGV`.
+
+* Python installs a small number of signal handlers by default: :const:`SIGPIPE`
+ is ignored (so write errors on pipes and sockets can be reported as ordinary
+ Python exceptions) and :const:`SIGINT` is translated into a
+ :exc:`KeyboardInterrupt` exception. All of these can be overridden.
+
+* Some care must be taken if both signals and threads are used in the same
+ program. The fundamental thing to remember in using signals and threads
+ simultaneously is: always perform :func:`signal` operations in the main thread
+ of execution. Any thread can perform an :func:`alarm`, :func:`getsignal`, or
+ :func:`pause`; only the main thread can set a new signal handler, and the main
+ thread will be the only one to receive signals (this is enforced by the Python
+ :mod:`signal` module, even if the underlying thread implementation supports
+ sending signals to individual threads). This means that signals can't be used
+ as a means of inter-thread communication. Use locks instead.
+
+The variables defined in the :mod:`signal` module are:
+
+
+.. data:: SIG_DFL
+
+ This is one of two standard signal handling options; it will simply perform the
+ default function for the signal. For example, on most systems the default
+ action for :const:`SIGQUIT` is to dump core and exit, while the default action
+ for :const:`SIGCLD` is to simply ignore it.
+
+
+.. data:: SIG_IGN
+
+ This is another standard signal handler, which will simply ignore the given
+ signal.
+
+
+.. data:: SIG*
+
+ All the signal numbers are defined symbolically. For example, the hangup signal
+ is defined as :const:`signal.SIGHUP`; the variable names are identical to the
+ names used in C programs, as found in ``<signal.h>``. The Unix man page for
+ ':cfunc:`signal`' lists the existing signals (on some systems this is
+ :manpage:`signal(2)`, on others the list is in :manpage:`signal(7)`). Note that
+ not all systems define the same set of signal names; only those names defined by
+ the system are defined by this module.
+
+
+.. data:: NSIG
+
+ One more than the number of the highest signal number.
+
+The :mod:`signal` module defines the following functions:
+
+
+.. function:: alarm(time)
+
+ If *time* is non-zero, this function requests that a :const:`SIGALRM` signal be
+ sent to the process in *time* seconds. Any previously scheduled alarm is
+ canceled (only one alarm can be scheduled at any time). The returned value is
+ then the number of seconds before any previously set alarm was to have been
+ delivered. If *time* is zero, no alarm is scheduled, and any scheduled alarm is
+ canceled. If the return value is zero, no alarm is currently scheduled. (See
+ the Unix man page :manpage:`alarm(2)`.) Availability: Unix.
+
+
+.. function:: getsignal(signalnum)
+
+ Return the current signal handler for the signal *signalnum*. The returned value
+ may be a callable Python object, or one of the special values
+ :const:`signal.SIG_IGN`, :const:`signal.SIG_DFL` or :const:`None`. Here,
+ :const:`signal.SIG_IGN` means that the signal was previously ignored,
+ :const:`signal.SIG_DFL` means that the default way of handling the signal was
+ previously in use, and ``None`` means that the previous signal handler was not
+ installed from Python.
+
+
+.. function:: pause()
+
+ Cause the process to sleep until a signal is received; the appropriate handler
+ will then be called. Returns nothing. Not on Windows. (See the Unix man page
+ :manpage:`signal(2)`.)
+
+
+.. function:: signal(signalnum, handler)
+
+ Set the handler for signal *signalnum* to the function *handler*. *handler* can
+ be a callable Python object taking two arguments (see below), or one of the
+ special values :const:`signal.SIG_IGN` or :const:`signal.SIG_DFL`. The previous
+ signal handler will be returned (see the description of :func:`getsignal`
+ above). (See the Unix man page :manpage:`signal(2)`.)
+
+ When threads are enabled, this function can only be called from the main thread;
+ attempting to call it from other threads will cause a :exc:`ValueError`
+ exception to be raised.
+
+ The *handler* is called with two arguments: the signal number and the current
+ stack frame (``None`` or a frame object; for a description of frame objects, see
+ the reference manual section on the standard type hierarchy or see the attribute
+ descriptions in the :mod:`inspect` module).
+
+
+.. _signal-example:
+
+Example
+-------
+
+Here is a minimal example program. It uses the :func:`alarm` function to limit
+the time spent waiting to open a file; this is useful if the file is for a
+serial device that may not be turned on, which would normally cause the
+:func:`os.open` to hang indefinitely. The solution is to set a 5-second alarm
+before opening the file; if the operation takes too long, the alarm signal will
+be sent, and the handler raises an exception. ::
+
+ import signal, os
+
+ def handler(signum, frame):
+ print 'Signal handler called with signal', signum
+ raise IOError, "Couldn't open device!"
+
+ # Set the signal handler and a 5-second alarm
+ signal.signal(signal.SIGALRM, handler)
+ signal.alarm(5)
+
+ # This open() may hang indefinitely
+ fd = os.open('/dev/ttyS0', os.O_RDWR)
+
+ signal.alarm(0) # Disable the alarm
+
diff --git a/Doc/library/simplehttpserver.rst b/Doc/library/simplehttpserver.rst
new file mode 100644
index 0000000000..766253ea23
--- /dev/null
+++ b/Doc/library/simplehttpserver.rst
@@ -0,0 +1,86 @@
+
+:mod:`SimpleHTTPServer` --- Simple HTTP request handler
+=======================================================
+
+.. module:: SimpleHTTPServer
+ :synopsis: This module provides a basic request handler for HTTP servers.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`SimpleHTTPServer` module defines a request-handler class,
+interface-compatible with :class:`BaseHTTPServer.BaseHTTPRequestHandler`, that
+serves files only from a base directory.
+
+The :mod:`SimpleHTTPServer` module defines the following class:
+
+
+.. class:: SimpleHTTPRequestHandler(request, client_address, server)
+
+ This class is used to serve files from the current directory and below, directly
+ mapping the directory structure to HTTP requests.
+
+ A lot of the work, such as parsing the request, is done by the base class
+ :class:`BaseHTTPServer.BaseHTTPRequestHandler`. This class implements the
+ :func:`do_GET` and :func:`do_HEAD` functions.
+
+The :class:`SimpleHTTPRequestHandler` defines the following member variables:
+
+
+.. attribute:: SimpleHTTPRequestHandler.server_version
+
+ This will be ``"SimpleHTTP/" + __version__``, where ``__version__`` is defined
+ in the module.
+
+
+.. attribute:: SimpleHTTPRequestHandler.extensions_map
+
+ A dictionary mapping suffixes into MIME types. The default is signified by an
+ empty string, and is considered to be ``application/octet-stream``. The mapping
+ is used case-insensitively, and so should contain only lower-cased keys.
+
+The :class:`SimpleHTTPRequestHandler` defines the following methods:
+
+
+.. method:: SimpleHTTPRequestHandler.do_HEAD()
+
+ This method serves the ``'HEAD'`` request type: it sends the headers it would
+ send for the equivalent ``GET`` request. See the :meth:`do_GET` method for a
+ more complete explanation of the possible headers.
+
+
+.. method:: SimpleHTTPRequestHandler.do_GET()
+
+ The request is mapped to a local file by interpreting the request as a path
+ relative to the current working directory.
+
+ If the request was mapped to a directory, the directory is checked for a file
+ named ``index.html`` or ``index.htm`` (in that order). If found, the file's
+ contents are returned; otherwise a directory listing is generated by calling the
+ :meth:`list_directory` method. This method uses :func:`os.listdir` to scan the
+ directory, and returns a ``404`` error response if the :func:`listdir` fails.
+
+ If the request was mapped to a file, it is opened and the contents are returned.
+ Any :exc:`IOError` exception in opening the requested file is mapped to a
+ ``404``, ``'File not found'`` error. Otherwise, the content type is guessed by
+ calling the :meth:`guess_type` method, which in turn uses the *extensions_map*
+ variable.
+
+ A ``'Content-type:'`` header with the guessed content type is output, followed
+ by a ``'Content-Length:'`` header with the file's size and a
+ ``'Last-Modified:'`` header with the file's modification time.
+
+ Then follows a blank line signifying the end of the headers, and then the
+ contents of the file are output. If the file's MIME type starts with ``text/``
+ the file is opened in text mode; otherwise binary mode is used.
+
+ For example usage, see the implementation of the :func:`test` function.
+
+ .. versionadded:: 2.5
+ The ``'Last-Modified'`` header.
+
+
+.. seealso::
+
+ Module :mod:`BaseHTTPServer`
+ Base class implementation for Web server and request handler.
+
diff --git a/Doc/library/simplexmlrpcserver.rst b/Doc/library/simplexmlrpcserver.rst
new file mode 100644
index 0000000000..51ce8d84c0
--- /dev/null
+++ b/Doc/library/simplexmlrpcserver.rst
@@ -0,0 +1,232 @@
+
+:mod:`SimpleXMLRPCServer` --- Basic XML-RPC server
+==================================================
+
+.. module:: SimpleXMLRPCServer
+ :synopsis: Basic XML-RPC server implementation.
+.. moduleauthor:: Brian Quinlan <brianq@activestate.com>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. versionadded:: 2.2
+
+The :mod:`SimpleXMLRPCServer` module provides a basic server framework for
+XML-RPC servers written in Python. Servers can either be free standing, using
+:class:`SimpleXMLRPCServer`, or embedded in a CGI environment, using
+:class:`CGIXMLRPCRequestHandler`.
+
+
+.. class:: SimpleXMLRPCServer(addr[, requestHandler[, logRequests[, allow_none[, encoding]]]])
+
+ Create a new server instance. This class provides methods for registration of
+ functions that can be called by the XML-RPC protocol. The *requestHandler*
+ parameter should be a factory for request handler instances; it defaults to
+ :class:`SimpleXMLRPCRequestHandler`. The *addr* and *requestHandler* parameters
+ are passed to the :class:`SocketServer.TCPServer` constructor. If *logRequests*
+ is true (the default), requests will be logged; setting this parameter to false
+ will turn off logging. The *allow_none* and *encoding* parameters are passed
+ on to :mod:`xmlrpclib` and control the XML-RPC responses that will be returned
+ from the server. The *bind_and_activate* parameter controls whether
+ :meth:`server_bind` and :meth:`server_activate` are called immediately by the
+ constructor; it defaults to true. Setting it to false allows code to manipulate
+ the *allow_reuse_address* class variable before the address is bound.
+
+ .. versionchanged:: 2.5
+ The *allow_none* and *encoding* parameters were added.
+
+ .. versionchanged:: 2.6
+ The *bind_and_activate* parameter was added.
+
+
+.. class:: CGIXMLRPCRequestHandler([allow_none[, encoding]])
+
+ Create a new instance to handle XML-RPC requests in a CGI environment. The
+ *allow_none* and *encoding* parameters are passed on to :mod:`xmlrpclib` and
+ control the XML-RPC responses that will be returned from the server.
+
+ .. versionadded:: 2.3
+
+ .. versionchanged:: 2.5
+ The *allow_none* and *encoding* parameters were added.
+
+
+.. class:: SimpleXMLRPCRequestHandler()
+
+ Create a new request handler instance. This request handler supports ``POST``
+ requests and modifies logging so that the *logRequests* parameter to the
+ :class:`SimpleXMLRPCServer` constructor parameter is honored.
+
+
+.. _simple-xmlrpc-servers:
+
+SimpleXMLRPCServer Objects
+--------------------------
+
+The :class:`SimpleXMLRPCServer` class is based on
+:class:`SocketServer.TCPServer` and provides a means of creating simple, stand
+alone XML-RPC servers.
+
+
+.. method:: SimpleXMLRPCServer.register_function(function[, name])
+
+ Register a function that can respond to XML-RPC requests. If *name* is given,
+ it will be the method name associated with *function*, otherwise
+ ``function.__name__`` will be used. *name* can be either a normal or Unicode
+ string, and may contain characters not legal in Python identifiers, including
+ the period character.
+
+
+.. method:: SimpleXMLRPCServer.register_instance(instance[, allow_dotted_names])
+
+ Register an object which is used to expose method names which have not been
+ registered using :meth:`register_function`. If *instance* contains a
+ :meth:`_dispatch` method, it is called with the requested method name and the
+ parameters from the request. Its API is ``def _dispatch(self, method, params)``
+ (note that *params* does not represent a variable argument list). If it calls
+ an underlying function to perform its task, that function is called as
+ ``func(*params)``, expanding the parameter list. The return value from
+ :meth:`_dispatch` is returned to the client as the result. If *instance* does
+ not have a :meth:`_dispatch` method, it is searched for an attribute matching
+ the name of the requested method.
+
+ If the optional *allow_dotted_names* argument is true and the instance does not
+ have a :meth:`_dispatch` method, then if the requested method name contains
+ periods, each component of the method name is searched for individually, with
+ the effect that a simple hierarchical search is performed. The value found from
+ this search is then called with the parameters from the request, and the return
+ value is passed back to the client.
+
+ .. warning::
+
+ Enabling the *allow_dotted_names* option allows intruders to access your
+ module's global variables and may allow intruders to execute arbitrary code on
+ your machine. Only use this option on a secure, closed network.
+
+ .. versionchanged:: 2.3.5, 2.4.1
+ *allow_dotted_names* was added to plug a security hole; prior versions are
+ insecure.
+
+
+.. method:: SimpleXMLRPCServer.register_introspection_functions()
+
+ Registers the XML-RPC introspection functions ``system.listMethods``,
+ ``system.methodHelp`` and ``system.methodSignature``.
+
+ .. versionadded:: 2.3
+
+
+.. method:: SimpleXMLRPCServer.register_multicall_functions()
+
+ Registers the XML-RPC multicall function system.multicall.
+
+
+.. attribute:: SimpleXMLRPCServer.rpc_paths
+
+ An attribute value that must be a tuple listing valid path portions of the URL
+ for receiving XML-RPC requests. Requests posted to other paths will result in a
+ 404 "no such page" HTTP error. If this tuple is empty, all paths will be
+ considered valid. The default value is ``('/', '/RPC2')``.
+
+ .. versionadded:: 2.5
+
+Example::
+
+ from SimpleXMLRPCServer import SimpleXMLRPCServer
+
+ # Create server
+ server = SimpleXMLRPCServer(("localhost", 8000))
+ server.register_introspection_functions()
+
+ # Register pow() function; this will use the value of
+ # pow.__name__ as the name, which is just 'pow'.
+ server.register_function(pow)
+
+ # Register a function under a different name
+ def adder_function(x,y):
+ return x + y
+ server.register_function(adder_function, 'add')
+
+ # Register an instance; all the methods of the instance are
+ # published as XML-RPC methods (in this case, just 'div').
+ class MyFuncs:
+ def div(self, x, y):
+ return x // y
+
+ server.register_instance(MyFuncs())
+
+ # Run the server's main loop
+ server.serve_forever()
+
+The following client code will call the methods made available by the preceding
+server::
+
+ import xmlrpclib
+
+ s = xmlrpclib.Server('http://localhost:8000')
+ print s.pow(2,3) # Returns 2**3 = 8
+ print s.add(2,3) # Returns 5
+ print s.div(5,2) # Returns 5//2 = 2
+
+ # Print list of available methods
+ print s.system.listMethods()
+
+
+CGIXMLRPCRequestHandler
+-----------------------
+
+The :class:`CGIXMLRPCRequestHandler` class can be used to handle XML-RPC
+requests sent to Python CGI scripts.
+
+
+.. method:: CGIXMLRPCRequestHandler.register_function(function[, name])
+
+ Register a function that can respond to XML-RPC requests. If *name* is given,
+ it will be the method name associated with function, otherwise
+ *function.__name__* will be used. *name* can be either a normal or Unicode
+ string, and may contain characters not legal in Python identifiers, including
+ the period character.
+
+
+.. method:: CGIXMLRPCRequestHandler.register_instance(instance)
+
+ Register an object which is used to expose method names which have not been
+ registered using :meth:`register_function`. If instance contains a
+ :meth:`_dispatch` method, it is called with the requested method name and the
+ parameters from the request; the return value is returned to the client as the
+ result. If instance does not have a :meth:`_dispatch` method, it is searched
+ for an attribute matching the name of the requested method; if the requested
+ method name contains periods, each component of the method name is searched for
+ individually, with the effect that a simple hierarchical search is performed.
+ The value found from this search is then called with the parameters from the
+ request, and the return value is passed back to the client.
+
+
+.. method:: CGIXMLRPCRequestHandler.register_introspection_functions()
+
+ Register the XML-RPC introspection functions ``system.listMethods``,
+ ``system.methodHelp`` and ``system.methodSignature``.
+
+
+.. method:: CGIXMLRPCRequestHandler.register_multicall_functions()
+
+ Register the XML-RPC multicall function ``system.multicall``.
+
+
+.. method:: CGIXMLRPCRequestHandler.handle_request([request_text = None])
+
+ Handle a XML-RPC request. If *request_text* is given, it should be the POST
+ data provided by the HTTP server, otherwise the contents of stdin will be used.
+
+Example::
+
+ class MyFuncs:
+ def div(self, x, y) : return x // y
+
+
+ handler = CGIXMLRPCRequestHandler()
+ handler.register_function(pow)
+ handler.register_function(lambda x,y: x+y, 'add')
+ handler.register_introspection_functions()
+ handler.register_instance(MyFuncs())
+ handler.handle_request()
+
diff --git a/Doc/library/site.rst b/Doc/library/site.rst
new file mode 100644
index 0000000000..4e549009f2
--- /dev/null
+++ b/Doc/library/site.rst
@@ -0,0 +1,87 @@
+
+:mod:`site` --- Site-specific configuration hook
+================================================
+
+.. module:: site
+ :synopsis: A standard way to reference site-specific modules.
+
+
+**This module is automatically imported during initialization.** The automatic
+import can be suppressed using the interpreter's :option:`-S` option.
+
+.. index:: triple: module; search; path
+
+Importing this module will append site-specific paths to the module search path.
+
+.. index::
+ pair: site-python; directory
+ pair: site-packages; directory
+
+It starts by constructing up to four directories from a head and a tail part.
+For the head part, it uses ``sys.prefix`` and ``sys.exec_prefix``; empty heads
+are skipped. For the tail part, it uses the empty string and then
+:file:`lib/site-packages` (on Windows) or
+:file:`lib/python|version|/site-packages` and then :file:`lib/site-python` (on
+Unix and Macintosh). For each of the distinct head-tail combinations, it sees
+if it refers to an existing directory, and if so, adds it to ``sys.path`` and
+also inspects the newly added path for configuration files.
+
+A path configuration file is a file whose name has the form :file:`package.pth`
+and exists in one of the four directories mentioned above; its contents are
+additional items (one per line) to be added to ``sys.path``. Non-existing items
+are never added to ``sys.path``, but no check is made that the item refers to a
+directory (rather than a file). No item is added to ``sys.path`` more than
+once. Blank lines and lines beginning with ``#`` are skipped. Lines starting
+with ``import`` (followed by space or tab) are executed.
+
+.. versionchanged:: 2.6
+ A space or tab is now required after the import keyword.
+
+.. index::
+ single: package
+ triple: path; configuration; file
+
+For example, suppose ``sys.prefix`` and ``sys.exec_prefix`` are set to
+:file:`/usr/local`. The Python X.Y library is then installed in
+:file:`/usr/local/lib/python{X.Y}` (where only the first three characters of
+``sys.version`` are used to form the installation path name). Suppose this has
+a subdirectory :file:`/usr/local/lib/python{X.Y}/site-packages` with three
+subsubdirectories, :file:`foo`, :file:`bar` and :file:`spam`, and two path
+configuration files, :file:`foo.pth` and :file:`bar.pth`. Assume
+:file:`foo.pth` contains the following::
+
+ # foo package configuration
+
+ foo
+ bar
+ bletch
+
+and :file:`bar.pth` contains::
+
+ # bar package configuration
+
+ bar
+
+Then the following directories are added to ``sys.path``, in this order::
+
+ /usr/local/lib/python2.3/site-packages/bar
+ /usr/local/lib/python2.3/site-packages/foo
+
+Note that :file:`bletch` is omitted because it doesn't exist; the :file:`bar`
+directory precedes the :file:`foo` directory because :file:`bar.pth` comes
+alphabetically before :file:`foo.pth`; and :file:`spam` is omitted because it is
+not mentioned in either path configuration file.
+
+.. index:: module: sitecustomize
+
+After these path manipulations, an attempt is made to import a module named
+:mod:`sitecustomize`, which can perform arbitrary site-specific customizations.
+If this import fails with an :exc:`ImportError` exception, it is silently
+ignored.
+
+.. index:: module: sitecustomize
+
+Note that for some non-Unix systems, ``sys.prefix`` and ``sys.exec_prefix`` are
+empty, and the path manipulations are skipped; however the import of
+:mod:`sitecustomize` is still attempted.
+
diff --git a/Doc/library/smtpd.rst b/Doc/library/smtpd.rst
new file mode 100644
index 0000000000..8927a64f4e
--- /dev/null
+++ b/Doc/library/smtpd.rst
@@ -0,0 +1,72 @@
+:mod:`smtpd` --- SMTP Server
+============================
+
+.. module:: smtpd
+ :synopsis: A SMTP server implementation in Python.
+
+.. moduleauthor:: Barry Warsaw <barry@zope.com>
+.. sectionauthor:: Moshe Zadka <moshez@moshez.org>
+
+
+
+
+This module offers several classes to implement SMTP servers. One is a generic
+do-nothing implementation, which can be overridden, while the other two offer
+specific mail-sending strategies.
+
+
+SMTPServer Objects
+------------------
+
+
+.. class:: SMTPServer(localaddr, remoteaddr)
+
+ Create a new :class:`SMTPServer` object, which binds to local address
+ *localaddr*. It will treat *remoteaddr* as an upstream SMTP relayer. It
+ inherits from :class:`asyncore.dispatcher`, and so will insert itself into
+ :mod:`asyncore`'s event loop on instantiation.
+
+
+.. method:: SMTPServer.process_message(peer, mailfrom, rcpttos, data)
+
+ Raise :exc:`NotImplementedError` exception. Override this in subclasses to do
+ something useful with this message. Whatever was passed in the constructor as
+ *remoteaddr* will be available as the :attr:`_remoteaddr` attribute. *peer* is
+ the remote host's address, *mailfrom* is the envelope originator, *rcpttos* are
+ the envelope recipients and *data* is a string containing the contents of the
+ e-mail (which should be in :rfc:`2822` format).
+
+
+DebuggingServer Objects
+-----------------------
+
+
+.. class:: DebuggingServer(localaddr, remoteaddr)
+
+ Create a new debugging server. Arguments are as per :class:`SMTPServer`.
+ Messages will be discarded, and printed on stdout.
+
+
+PureProxy Objects
+-----------------
+
+
+.. class:: PureProxy(localaddr, remoteaddr)
+
+ Create a new pure proxy server. Arguments are as per :class:`SMTPServer`.
+ Everything will be relayed to *remoteaddr*. Note that running this has a good
+ chance to make you into an open relay, so please be careful.
+
+
+MailmanProxy Objects
+--------------------
+
+
+.. class:: MailmanProxy(localaddr, remoteaddr)
+
+ Create a new pure proxy server. Arguments are as per :class:`SMTPServer`.
+ Everything will be relayed to *remoteaddr*, unless local mailman configurations
+ knows about an address, in which case it will be handled via mailman. Note that
+ running this has a good chance to make you into an open relay, so please be
+ careful.
+
diff --git a/Doc/library/smtplib.rst b/Doc/library/smtplib.rst
new file mode 100644
index 0000000000..fd898ca2d1
--- /dev/null
+++ b/Doc/library/smtplib.rst
@@ -0,0 +1,347 @@
+
+:mod:`smtplib` --- SMTP protocol client
+=======================================
+
+.. module:: smtplib
+ :synopsis: SMTP protocol client (requires sockets).
+.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+
+
+.. index::
+ pair: SMTP; protocol
+ single: Simple Mail Transfer Protocol
+
+The :mod:`smtplib` module defines an SMTP client session object that can be used
+to send mail to any Internet machine with an SMTP or ESMTP listener daemon. For
+details of SMTP and ESMTP operation, consult :rfc:`821` (Simple Mail Transfer
+Protocol) and :rfc:`1869` (SMTP Service Extensions).
+
+
+.. class:: SMTP([host[, port[, local_hostname[, timeout]]]])
+
+ A :class:`SMTP` instance encapsulates an SMTP connection. It has methods that
+ support a full repertoire of SMTP and ESMTP operations. If the optional host and
+ port parameters are given, the SMTP :meth:`connect` method is called with those
+ parameters during initialization. An :exc:`SMTPConnectError` is raised if the
+ specified host doesn't respond correctly. The optional *timeout* parameter
+ specifies a timeout in seconds for the connection attempt (if not specified, or
+ passed as None, the global default timeout setting will be used).
+
+ For normal use, you should only require the initialization/connect,
+ :meth:`sendmail`, and :meth:`quit` methods. An example is included below.
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. class:: SMTP_SSL([host[, port[, local_hostname[, keyfile[, certfile[, timeout]]]]]])
+
+ A :class:`SMTP_SSL` instance behaves exactly the same as instances of
+ :class:`SMTP`. :class:`SMTP_SSL` should be used for situations where SSL is
+ required from the beginning of the connection and using :meth:`starttls` is not
+ appropriate. If *host* is not specified, the local host is used. If *port* is
+ omitted, the standard SMTP-over-SSL port (465) is used. *keyfile* and *certfile*
+ are also optional, and can contain a PEM formatted private key and certificate
+ chain file for the SSL connection. The optional *timeout* parameter specifies a
+ timeout in seconds for the connection attempt (if not specified, or passed as
+ None, the global default timeout setting will be used).
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. class:: LMTP([host[, port[, local_hostname]]])
+
+ The LMTP protocol, which is very similar to ESMTP, is heavily based on the
+ standard SMTP client. It's common to use Unix sockets for LMTP, so our connect()
+ method must support that as well as a regular host:port server. To specify a
+ Unix socket, you must use an absolute path for *host*, starting with a '/'.
+
+ Authentication is supported, using the regular SMTP mechanism. When using a Unix
+ socket, LMTP generally don't support or require any authentication, but your
+ mileage might vary.
+
+ .. versionadded:: 2.6
+
+A nice selection of exceptions is defined as well:
+
+
+.. exception:: SMTPException
+
+ Base exception class for all exceptions raised by this module.
+
+
+.. exception:: SMTPServerDisconnected
+
+ This exception is raised when the server unexpectedly disconnects, or when an
+ attempt is made to use the :class:`SMTP` instance before connecting it to a
+ server.
+
+
+.. exception:: SMTPResponseException
+
+ Base class for all exceptions that include an SMTP error code. These exceptions
+ are generated in some instances when the SMTP server returns an error code. The
+ error code is stored in the :attr:`smtp_code` attribute of the error, and the
+ :attr:`smtp_error` attribute is set to the error message.
+
+
+.. exception:: SMTPSenderRefused
+
+ Sender address refused. In addition to the attributes set by on all
+ :exc:`SMTPResponseException` exceptions, this sets 'sender' to the string that
+ the SMTP server refused.
+
+
+.. exception:: SMTPRecipientsRefused
+
+ All recipient addresses refused. The errors for each recipient are accessible
+ through the attribute :attr:`recipients`, which is a dictionary of exactly the
+ same sort as :meth:`SMTP.sendmail` returns.
+
+
+.. exception:: SMTPDataError
+
+ The SMTP server refused to accept the message data.
+
+
+.. exception:: SMTPConnectError
+
+ Error occurred during establishment of a connection with the server.
+
+
+.. exception:: SMTPHeloError
+
+ The server refused our ``HELO`` message.
+
+
+.. exception:: SMTPAuthenticationError
+
+ SMTP authentication went wrong. Most probably the server didn't accept the
+ username/password combination provided.
+
+
+.. seealso::
+
+ :rfc:`821` - Simple Mail Transfer Protocol
+ Protocol definition for SMTP. This document covers the model, operating
+ procedure, and protocol details for SMTP.
+
+ :rfc:`1869` - SMTP Service Extensions
+ Definition of the ESMTP extensions for SMTP. This describes a framework for
+ extending SMTP with new commands, supporting dynamic discovery of the commands
+ provided by the server, and defines a few additional commands.
+
+
+.. _smtp-objects:
+
+SMTP Objects
+------------
+
+An :class:`SMTP` instance has the following methods:
+
+
+.. method:: SMTP.set_debuglevel(level)
+
+ Set the debug output level. A true value for *level* results in debug messages
+ for connection and for all messages sent to and received from the server.
+
+
+.. method:: SMTP.connect([host[, port]])
+
+ Connect to a host on a given port. The defaults are to connect to the local
+ host at the standard SMTP port (25). If the hostname ends with a colon (``':'``)
+ followed by a number, that suffix will be stripped off and the number
+ interpreted as the port number to use. This method is automatically invoked by
+ the constructor if a host is specified during instantiation.
+
+
+.. method:: SMTP.docmd(cmd, [, argstring])
+
+ Send a command *cmd* to the server. The optional argument *argstring* is simply
+ concatenated to the command, separated by a space.
+
+ This returns a 2-tuple composed of a numeric response code and the actual
+ response line (multiline responses are joined into one long line.)
+
+ In normal operation it should not be necessary to call this method explicitly.
+ It is used to implement other methods and may be useful for testing private
+ extensions.
+
+ If the connection to the server is lost while waiting for the reply,
+ :exc:`SMTPServerDisconnected` will be raised.
+
+
+.. method:: SMTP.helo([hostname])
+
+ Identify yourself to the SMTP server using ``HELO``. The hostname argument
+ defaults to the fully qualified domain name of the local host.
+
+ In normal operation it should not be necessary to call this method explicitly.
+ It will be implicitly called by the :meth:`sendmail` when necessary.
+
+
+.. method:: SMTP.ehlo([hostname])
+
+ Identify yourself to an ESMTP server using ``EHLO``. The hostname argument
+ defaults to the fully qualified domain name of the local host. Examine the
+ response for ESMTP option and store them for use by :meth:`has_extn`.
+
+ Unless you wish to use :meth:`has_extn` before sending mail, it should not be
+ necessary to call this method explicitly. It will be implicitly called by
+ :meth:`sendmail` when necessary.
+
+
+.. method:: SMTP.has_extn(name)
+
+ Return :const:`True` if *name* is in the set of SMTP service extensions returned
+ by the server, :const:`False` otherwise. Case is ignored.
+
+
+.. method:: SMTP.verify(address)
+
+ Check the validity of an address on this server using SMTP ``VRFY``. Returns a
+ tuple consisting of code 250 and a full :rfc:`822` address (including human
+ name) if the user address is valid. Otherwise returns an SMTP error code of 400
+ or greater and an error string.
+
+ .. note::
+
+ Many sites disable SMTP ``VRFY`` in order to foil spammers.
+
+
+.. method:: SMTP.login(user, password)
+
+ Log in on an SMTP server that requires authentication. The arguments are the
+ username and the password to authenticate with. If there has been no previous
+ ``EHLO`` or ``HELO`` command this session, this method tries ESMTP ``EHLO``
+ first. This method will return normally if the authentication was successful, or
+ may raise the following exceptions:
+
+ :exc:`SMTPHeloError`
+ The server didn't reply properly to the ``HELO`` greeting.
+
+ :exc:`SMTPAuthenticationError`
+ The server didn't accept the username/password combination.
+
+ :exc:`SMTPException`
+ No suitable authentication method was found.
+
+
+.. method:: SMTP.starttls([keyfile[, certfile]])
+
+ Put the SMTP connection in TLS (Transport Layer Security) mode. All SMTP
+ commands that follow will be encrypted. You should then call :meth:`ehlo`
+ again.
+
+ If *keyfile* and *certfile* are provided, these are passed to the :mod:`socket`
+ module's :func:`ssl` function.
+
+
+.. method:: SMTP.sendmail(from_addr, to_addrs, msg[, mail_options, rcpt_options])
+
+ Send mail. The required arguments are an :rfc:`822` from-address string, a list
+ of :rfc:`822` to-address strings (a bare string will be treated as a list with 1
+ address), and a message string. The caller may pass a list of ESMTP options
+ (such as ``8bitmime``) to be used in ``MAIL FROM`` commands as *mail_options*.
+ ESMTP options (such as ``DSN`` commands) that should be used with all ``RCPT``
+ commands can be passed as *rcpt_options*. (If you need to use different ESMTP
+ options to different recipients you have to use the low-level methods such as
+ :meth:`mail`, :meth:`rcpt` and :meth:`data` to send the message.)
+
+ .. note::
+
+ The *from_addr* and *to_addrs* parameters are used to construct the message
+ envelope used by the transport agents. The :class:`SMTP` does not modify the
+ message headers in any way.
+
+ If there has been no previous ``EHLO`` or ``HELO`` command this session, this
+ method tries ESMTP ``EHLO`` first. If the server does ESMTP, message size and
+ each of the specified options will be passed to it (if the option is in the
+ feature set the server advertises). If ``EHLO`` fails, ``HELO`` will be tried
+ and ESMTP options suppressed.
+
+ This method will return normally if the mail is accepted for at least one
+ recipient. Otherwise it will throw an exception. That is, if this method does
+ not throw an exception, then someone should get your mail. If this method does
+ not throw an exception, it returns a dictionary, with one entry for each
+ recipient that was refused. Each entry contains a tuple of the SMTP error code
+ and the accompanying error message sent by the server.
+
+ This method may raise the following exceptions:
+
+ :exc:`SMTPRecipientsRefused`
+ All recipients were refused. Nobody got the mail. The :attr:`recipients`
+ attribute of the exception object is a dictionary with information about the
+ refused recipients (like the one returned when at least one recipient was
+ accepted).
+
+ :exc:`SMTPHeloError`
+ The server didn't reply properly to the ``HELO`` greeting.
+
+ :exc:`SMTPSenderRefused`
+ The server didn't accept the *from_addr*.
+
+ :exc:`SMTPDataError`
+ The server replied with an unexpected error code (other than a refusal of a
+ recipient).
+
+ Unless otherwise noted, the connection will be open even after an exception is
+ raised.
+
+
+.. method:: SMTP.quit()
+
+ Terminate the SMTP session and close the connection.
+
+Low-level methods corresponding to the standard SMTP/ESMTP commands ``HELP``,
+``RSET``, ``NOOP``, ``MAIL``, ``RCPT``, and ``DATA`` are also supported.
+Normally these do not need to be called directly, so they are not documented
+here. For details, consult the module code.
+
+
+.. _smtp-example:
+
+SMTP Example
+------------
+
+This example prompts the user for addresses needed in the message envelope ('To'
+and 'From' addresses), and the message to be delivered. Note that the headers
+to be included with the message must be included in the message as entered; this
+example doesn't do any processing of the :rfc:`822` headers. In particular, the
+'To' and 'From' addresses must be included in the message headers explicitly. ::
+
+ import smtplib
+
+ def raw_input(prompt):
+ import sys
+ sys.stdout.write(prompt)
+ sys.stdout.flush()
+ return sys.stdin.readline()
+
+ def prompt(prompt):
+ return raw_input(prompt).strip()
+
+ fromaddr = prompt("From: ")
+ toaddrs = prompt("To: ").split()
+ print "Enter message, end with ^D (Unix) or ^Z (Windows):"
+
+ # Add the From: and To: headers at the start!
+ msg = ("From: %s\r\nTo: %s\r\n\r\n"
+ % (fromaddr, ", ".join(toaddrs)))
+ while 1:
+ try:
+ line = raw_input()
+ except EOFError:
+ break
+ if not line:
+ break
+ msg = msg + line
+
+ print "Message length is " + repr(len(msg))
+
+ server = smtplib.SMTP('localhost')
+ server.set_debuglevel(1)
+ server.sendmail(fromaddr, toaddrs, msg)
+ server.quit()
+
diff --git a/Doc/library/sndhdr.rst b/Doc/library/sndhdr.rst
new file mode 100644
index 0000000000..90d71a9ef5
--- /dev/null
+++ b/Doc/library/sndhdr.rst
@@ -0,0 +1,42 @@
+
+:mod:`sndhdr` --- Determine type of sound file
+==============================================
+
+.. module:: sndhdr
+ :synopsis: Determine type of a sound file.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. % Based on comments in the module source file.
+
+.. index::
+ single: A-LAW
+ single: u-LAW
+
+The :mod:`sndhdr` provides utility functions which attempt to determine the type
+of sound data which is in a file. When these functions are able to determine
+what type of sound data is stored in a file, they return a tuple ``(type,
+sampling_rate, channels, frames, bits_per_sample)``. The value for *type*
+indicates the data type and will be one of the strings ``'aifc'``, ``'aiff'``,
+``'au'``, ``'hcom'``, ``'sndr'``, ``'sndt'``, ``'voc'``, ``'wav'``, ``'8svx'``,
+``'sb'``, ``'ub'``, or ``'ul'``. The *sampling_rate* will be either the actual
+value or ``0`` if unknown or difficult to decode. Similarly, *channels* will be
+either the number of channels or ``0`` if it cannot be determined or if the
+value is difficult to decode. The value for *frames* will be either the number
+of frames or ``-1``. The last item in the tuple, *bits_per_sample*, will either
+be the sample size in bits or ``'A'`` for A-LAW or ``'U'`` for u-LAW.
+
+
+.. function:: what(filename)
+
+ Determines the type of sound data stored in the file *filename* using
+ :func:`whathdr`. If it succeeds, returns a tuple as described above, otherwise
+ ``None`` is returned.
+
+
+.. function:: whathdr(filename)
+
+ Determines the type of sound data stored in a file based on the file header.
+ The name of the file is given by *filename*. This function returns a tuple as
+ described above on success, or ``None``.
+
diff --git a/Doc/library/socket.rst b/Doc/library/socket.rst
new file mode 100644
index 0000000000..0ec44614fa
--- /dev/null
+++ b/Doc/library/socket.rst
@@ -0,0 +1,941 @@
+
+:mod:`socket` --- Low-level networking interface
+================================================
+
+.. module:: socket
+ :synopsis: Low-level networking interface.
+
+
+This module provides access to the BSD *socket* interface. It is available on
+all modern Unix systems, Windows, MacOS, BeOS, OS/2, and probably additional
+platforms.
+
+.. note::
+
+ Some behavior may be platform dependent, since calls are made to the operating
+ system socket APIs.
+
+For an introduction to socket programming (in C), see the following papers: An
+Introductory 4.3BSD Interprocess Communication Tutorial, by Stuart Sechrest and
+An Advanced 4.3BSD Interprocess Communication Tutorial, by Samuel J. Leffler et
+al, both in the UNIX Programmer's Manual, Supplementary Documents 1 (sections
+PS1:7 and PS1:8). The platform-specific reference material for the various
+socket-related system calls are also a valuable source of information on the
+details of socket semantics. For Unix, refer to the manual pages; for Windows,
+see the WinSock (or Winsock 2) specification. For IPv6-ready APIs, readers may
+want to refer to :rfc:`2553` titled Basic Socket Interface Extensions for IPv6.
+
+.. index:: object: socket
+
+The Python interface is a straightforward transliteration of the Unix system
+call and library interface for sockets to Python's object-oriented style: the
+:func:`socket` function returns a :dfn:`socket object` whose methods implement
+the various socket system calls. Parameter types are somewhat higher-level than
+in the C interface: as with :meth:`read` and :meth:`write` operations on Python
+files, buffer allocation on receive operations is automatic, and buffer length
+is implicit on send operations.
+
+Socket addresses are represented as follows: A single string is used for the
+:const:`AF_UNIX` address family. A pair ``(host, port)`` is used for the
+:const:`AF_INET` address family, where *host* is a string representing either a
+hostname in Internet domain notation like ``'daring.cwi.nl'`` or an IPv4 address
+like ``'100.50.200.5'``, and *port* is an integral port number. For
+:const:`AF_INET6` address family, a four-tuple ``(host, port, flowinfo,
+scopeid)`` is used, where *flowinfo* and *scopeid* represents ``sin6_flowinfo``
+and ``sin6_scope_id`` member in :const:`struct sockaddr_in6` in C. For
+:mod:`socket` module methods, *flowinfo* and *scopeid* can be omitted just for
+backward compatibility. Note, however, omission of *scopeid* can cause problems
+in manipulating scoped IPv6 addresses. Other address families are currently not
+supported. The address format required by a particular socket object is
+automatically selected based on the address family specified when the socket
+object was created.
+
+For IPv4 addresses, two special forms are accepted instead of a host address:
+the empty string represents :const:`INADDR_ANY`, and the string
+``'<broadcast>'`` represents :const:`INADDR_BROADCAST`. The behavior is not
+available for IPv6 for backward compatibility, therefore, you may want to avoid
+these if you intend to support IPv6 with your Python programs.
+
+If you use a hostname in the *host* portion of IPv4/v6 socket address, the
+program may show a nondeterministic behavior, as Python uses the first address
+returned from the DNS resolution. The socket address will be resolved
+differently into an actual IPv4/v6 address, depending on the results from DNS
+resolution and/or the host configuration. For deterministic behavior use a
+numeric address in *host* portion.
+
+.. versionadded:: 2.5
+ AF_NETLINK sockets are represented as pairs ``pid, groups``.
+
+All errors raise exceptions. The normal exceptions for invalid argument types
+and out-of-memory conditions can be raised; errors related to socket or address
+semantics raise the error :exc:`socket.error`.
+
+Non-blocking mode is supported through :meth:`setblocking`. A generalization of
+this based on timeouts is supported through :meth:`settimeout`.
+
+The module :mod:`socket` exports the following constants and functions:
+
+
+.. exception:: error
+
+ .. index:: module: errno
+
+ This exception is raised for socket-related errors. The accompanying value is
+ either a string telling what went wrong or a pair ``(errno, string)``
+ representing an error returned by a system call, similar to the value
+ accompanying :exc:`os.error`. See the module :mod:`errno`, which contains names
+ for the error codes defined by the underlying operating system.
+
+
+.. exception:: herror
+
+ This exception is raised for address-related errors, i.e. for functions that use
+ *h_errno* in the C API, including :func:`gethostbyname_ex` and
+ :func:`gethostbyaddr`.
+
+ The accompanying value is a pair ``(h_errno, string)`` representing an error
+ returned by a library call. *string* represents the description of *h_errno*, as
+ returned by the :cfunc:`hstrerror` C function.
+
+
+.. exception:: gaierror
+
+ This exception is raised for address-related errors, for :func:`getaddrinfo` and
+ :func:`getnameinfo`. The accompanying value is a pair ``(error, string)``
+ representing an error returned by a library call. *string* represents the
+ description of *error*, as returned by the :cfunc:`gai_strerror` C function. The
+ *error* value will match one of the :const:`EAI_\*` constants defined in this
+ module.
+
+
+.. exception:: timeout
+
+ This exception is raised when a timeout occurs on a socket which has had
+ timeouts enabled via a prior call to :meth:`settimeout`. The accompanying value
+ is a string whose value is currently always "timed out".
+
+ .. versionadded:: 2.3
+
+
+.. data:: AF_UNIX
+ AF_INET
+ AF_INET6
+
+ These constants represent the address (and protocol) families, used for the
+ first argument to :func:`socket`. If the :const:`AF_UNIX` constant is not
+ defined then this protocol is unsupported.
+
+
+.. data:: SOCK_STREAM
+ SOCK_DGRAM
+ SOCK_RAW
+ SOCK_RDM
+ SOCK_SEQPACKET
+
+ These constants represent the socket types, used for the second argument to
+ :func:`socket`. (Only :const:`SOCK_STREAM` and :const:`SOCK_DGRAM` appear to be
+ generally useful.)
+
+
+.. data:: SO_*
+ SOMAXCONN
+ MSG_*
+ SOL_*
+ IPPROTO_*
+ IPPORT_*
+ INADDR_*
+ IP_*
+ IPV6_*
+ EAI_*
+ AI_*
+ NI_*
+ TCP_*
+
+ Many constants of these forms, documented in the Unix documentation on sockets
+ and/or the IP protocol, are also defined in the socket module. They are
+ generally used in arguments to the :meth:`setsockopt` and :meth:`getsockopt`
+ methods of socket objects. In most cases, only those symbols that are defined
+ in the Unix header files are defined; for a few symbols, default values are
+ provided.
+
+
+.. data:: has_ipv6
+
+ This constant contains a boolean value which indicates if IPv6 is supported on
+ this platform.
+
+ .. versionadded:: 2.3
+
+
+.. function:: create_connection(address[, timeout])
+
+ Connects to the *address* received (as usual, a ``(host, port)`` pair), with an
+ optional timeout for the connection. Specially useful for higher-level
+ protocols, it is not normally used directly from application-level code.
+ Passing the optional *timeout* parameter will set the timeout on the socket
+ instance (if it is not given or ``None``, the global default timeout setting is
+ used).
+
+ .. versionadded:: 2.6
+
+
+.. function:: getaddrinfo(host, port[, family[, socktype[, proto[, flags]]]])
+
+ Resolves the *host*/*port* argument, into a sequence of 5-tuples that contain
+ all the necessary argument for the sockets manipulation. *host* is a domain
+ name, a string representation of IPv4/v6 address or ``None``. *port* is a string
+ service name (like ``'http'``), a numeric port number or ``None``.
+
+ The rest of the arguments are optional and must be numeric if specified. For
+ *host* and *port*, by passing either an empty string or ``None``, you can pass
+ ``NULL`` to the C API. The :func:`getaddrinfo` function returns a list of
+ 5-tuples with the following structure:
+
+ ``(family, socktype, proto, canonname, sockaddr)``
+
+ *family*, *socktype*, *proto* are all integer and are meant to be passed to the
+ :func:`socket` function. *canonname* is a string representing the canonical name
+ of the *host*. It can be a numeric IPv4/v6 address when :const:`AI_CANONNAME` is
+ specified for a numeric *host*. *sockaddr* is a tuple describing a socket
+ address, as described above. See the source for the :mod:`httplib` and other
+ library modules for a typical usage of the function.
+
+ .. versionadded:: 2.2
+
+
+.. function:: getfqdn([name])
+
+ Return a fully qualified domain name for *name*. If *name* is omitted or empty,
+ it is interpreted as the local host. To find the fully qualified name, the
+ hostname returned by :func:`gethostbyaddr` is checked, then aliases for the
+ host, if available. The first name which includes a period is selected. In
+ case no fully qualified domain name is available, the hostname as returned by
+ :func:`gethostname` is returned.
+
+ .. versionadded:: 2.0
+
+
+.. function:: gethostbyname(hostname)
+
+ Translate a host name to IPv4 address format. The IPv4 address is returned as a
+ string, such as ``'100.50.200.5'``. If the host name is an IPv4 address itself
+ it is returned unchanged. See :func:`gethostbyname_ex` for a more complete
+ interface. :func:`gethostbyname` does not support IPv6 name resolution, and
+ :func:`getaddrinfo` should be used instead for IPv4/v6 dual stack support.
+
+
+.. function:: gethostbyname_ex(hostname)
+
+ Translate a host name to IPv4 address format, extended interface. Return a
+ triple ``(hostname, aliaslist, ipaddrlist)`` where *hostname* is the primary
+ host name responding to the given *ip_address*, *aliaslist* is a (possibly
+ empty) list of alternative host names for the same address, and *ipaddrlist* is
+ a list of IPv4 addresses for the same interface on the same host (often but not
+ always a single address). :func:`gethostbyname_ex` does not support IPv6 name
+ resolution, and :func:`getaddrinfo` should be used instead for IPv4/v6 dual
+ stack support.
+
+
+.. function:: gethostname()
+
+ Return a string containing the hostname of the machine where the Python
+ interpreter is currently executing. If you want to know the current machine's IP
+ address, you may want to use ``gethostbyname(gethostname())``. This operation
+ assumes that there is a valid address-to-host mapping for the host, and the
+ assumption does not always hold. Note: :func:`gethostname` doesn't always return
+ the fully qualified domain name; use ``getfqdn()`` (see above).
+
+
+.. function:: gethostbyaddr(ip_address)
+
+ Return a triple ``(hostname, aliaslist, ipaddrlist)`` where *hostname* is the
+ primary host name responding to the given *ip_address*, *aliaslist* is a
+ (possibly empty) list of alternative host names for the same address, and
+ *ipaddrlist* is a list of IPv4/v6 addresses for the same interface on the same
+ host (most likely containing only a single address). To find the fully qualified
+ domain name, use the function :func:`getfqdn`. :func:`gethostbyaddr` supports
+ both IPv4 and IPv6.
+
+
+.. function:: getnameinfo(sockaddr, flags)
+
+ Translate a socket address *sockaddr* into a 2-tuple ``(host, port)``. Depending
+ on the settings of *flags*, the result can contain a fully-qualified domain name
+ or numeric address representation in *host*. Similarly, *port* can contain a
+ string port name or a numeric port number.
+
+ .. versionadded:: 2.2
+
+
+.. function:: getprotobyname(protocolname)
+
+ Translate an Internet protocol name (for example, ``'icmp'``) to a constant
+ suitable for passing as the (optional) third argument to the :func:`socket`
+ function. This is usually only needed for sockets opened in "raw" mode
+ (:const:`SOCK_RAW`); for the normal socket modes, the correct protocol is chosen
+ automatically if the protocol is omitted or zero.
+
+
+.. function:: getservbyname(servicename[, protocolname])
+
+ Translate an Internet service name and protocol name to a port number for that
+ service. The optional protocol name, if given, should be ``'tcp'`` or
+ ``'udp'``, otherwise any protocol will match.
+
+
+.. function:: getservbyport(port[, protocolname])
+
+ Translate an Internet port number and protocol name to a service name for that
+ service. The optional protocol name, if given, should be ``'tcp'`` or
+ ``'udp'``, otherwise any protocol will match.
+
+
+.. function:: socket([family[, type[, proto]]])
+
+ Create a new socket using the given address family, socket type and protocol
+ number. The address family should be :const:`AF_INET` (the default),
+ :const:`AF_INET6` or :const:`AF_UNIX`. The socket type should be
+ :const:`SOCK_STREAM` (the default), :const:`SOCK_DGRAM` or perhaps one of the
+ other ``SOCK_`` constants. The protocol number is usually zero and may be
+ omitted in that case.
+
+
+.. function:: ssl(sock[, keyfile, certfile])
+
+ Initiate a SSL connection over the socket *sock*. *keyfile* is the name of a PEM
+ formatted file that contains your private key. *certfile* is a PEM formatted
+ certificate chain file. On success, a new :class:`SSLObject` is returned.
+
+ .. warning::
+
+ This does not do any certificate verification!
+
+
+.. function:: socketpair([family[, type[, proto]]])
+
+ Build a pair of connected socket objects using the given address family, socket
+ type, and protocol number. Address family, socket type, and protocol number are
+ as for the :func:`socket` function above. The default family is :const:`AF_UNIX`
+ if defined on the platform; otherwise, the default is :const:`AF_INET`.
+ Availability: Unix.
+
+ .. versionadded:: 2.4
+
+
+.. function:: fromfd(fd, family, type[, proto])
+
+ Duplicate the file descriptor *fd* (an integer as returned by a file object's
+ :meth:`fileno` method) and build a socket object from the result. Address
+ family, socket type and protocol number are as for the :func:`socket` function
+ above. The file descriptor should refer to a socket, but this is not checked ---
+ subsequent operations on the object may fail if the file descriptor is invalid.
+ This function is rarely needed, but can be used to get or set socket options on
+ a socket passed to a program as standard input or output (such as a server
+ started by the Unix inet daemon). The socket is assumed to be in blocking mode.
+ Availability: Unix.
+
+
+.. function:: ntohl(x)
+
+ Convert 32-bit positive integers from network to host byte order. On machines
+ where the host byte order is the same as network byte order, this is a no-op;
+ otherwise, it performs a 4-byte swap operation.
+
+
+.. function:: ntohs(x)
+
+ Convert 16-bit positive integers from network to host byte order. On machines
+ where the host byte order is the same as network byte order, this is a no-op;
+ otherwise, it performs a 2-byte swap operation.
+
+
+.. function:: htonl(x)
+
+ Convert 32-bit positive integers from host to network byte order. On machines
+ where the host byte order is the same as network byte order, this is a no-op;
+ otherwise, it performs a 4-byte swap operation.
+
+
+.. function:: htons(x)
+
+ Convert 16-bit positive integers from host to network byte order. On machines
+ where the host byte order is the same as network byte order, this is a no-op;
+ otherwise, it performs a 2-byte swap operation.
+
+
+.. function:: inet_aton(ip_string)
+
+ Convert an IPv4 address from dotted-quad string format (for example,
+ '123.45.67.89') to 32-bit packed binary format, as a string four characters in
+ length. This is useful when conversing with a program that uses the standard C
+ library and needs objects of type :ctype:`struct in_addr`, which is the C type
+ for the 32-bit packed binary this function returns.
+
+ If the IPv4 address string passed to this function is invalid,
+ :exc:`socket.error` will be raised. Note that exactly what is valid depends on
+ the underlying C implementation of :cfunc:`inet_aton`.
+
+ :func:`inet_aton` does not support IPv6, and :func:`getnameinfo` should be used
+ instead for IPv4/v6 dual stack support.
+
+
+.. function:: inet_ntoa(packed_ip)
+
+ Convert a 32-bit packed IPv4 address (a string four characters in length) to its
+ standard dotted-quad string representation (for example, '123.45.67.89'). This
+ is useful when conversing with a program that uses the standard C library and
+ needs objects of type :ctype:`struct in_addr`, which is the C type for the
+ 32-bit packed binary data this function takes as an argument.
+
+ If the string passed to this function is not exactly 4 bytes in length,
+ :exc:`socket.error` will be raised. :func:`inet_ntoa` does not support IPv6, and
+ :func:`getnameinfo` should be used instead for IPv4/v6 dual stack support.
+
+
+.. function:: inet_pton(address_family, ip_string)
+
+ Convert an IP address from its family-specific string format to a packed, binary
+ format. :func:`inet_pton` is useful when a library or network protocol calls for
+ an object of type :ctype:`struct in_addr` (similar to :func:`inet_aton`) or
+ :ctype:`struct in6_addr`.
+
+ Supported values for *address_family* are currently :const:`AF_INET` and
+ :const:`AF_INET6`. If the IP address string *ip_string* is invalid,
+ :exc:`socket.error` will be raised. Note that exactly what is valid depends on
+ both the value of *address_family* and the underlying implementation of
+ :cfunc:`inet_pton`.
+
+ Availability: Unix (maybe not all platforms).
+
+ .. versionadded:: 2.3
+
+
+.. function:: inet_ntop(address_family, packed_ip)
+
+ Convert a packed IP address (a string of some number of characters) to its
+ standard, family-specific string representation (for example, ``'7.10.0.5'`` or
+ ``'5aef:2b::8'``) :func:`inet_ntop` is useful when a library or network protocol
+ returns an object of type :ctype:`struct in_addr` (similar to :func:`inet_ntoa`)
+ or :ctype:`struct in6_addr`.
+
+ Supported values for *address_family* are currently :const:`AF_INET` and
+ :const:`AF_INET6`. If the string *packed_ip* is not the correct length for the
+ specified address family, :exc:`ValueError` will be raised. A
+ :exc:`socket.error` is raised for errors from the call to :func:`inet_ntop`.
+
+ Availability: Unix (maybe not all platforms).
+
+ .. versionadded:: 2.3
+
+
+.. function:: getdefaulttimeout()
+
+ Return the default timeout in floating seconds for new socket objects. A value
+ of ``None`` indicates that new socket objects have no timeout. When the socket
+ module is first imported, the default is ``None``.
+
+ .. versionadded:: 2.3
+
+
+.. function:: setdefaulttimeout(timeout)
+
+ Set the default timeout in floating seconds for new socket objects. A value of
+ ``None`` indicates that new socket objects have no timeout. When the socket
+ module is first imported, the default is ``None``.
+
+ .. versionadded:: 2.3
+
+
+.. data:: SocketType
+
+ This is a Python type object that represents the socket object type. It is the
+ same as ``type(socket(...))``.
+
+
+.. seealso::
+
+ Module :mod:`SocketServer`
+ Classes that simplify writing network servers.
+
+
+.. _socket-objects:
+
+Socket Objects
+--------------
+
+Socket objects have the following methods. Except for :meth:`makefile` these
+correspond to Unix system calls applicable to sockets.
+
+
+.. method:: socket.accept()
+
+ Accept a connection. The socket must be bound to an address and listening for
+ connections. The return value is a pair ``(conn, address)`` where *conn* is a
+ *new* socket object usable to send and receive data on the connection, and
+ *address* is the address bound to the socket on the other end of the connection.
+
+
+.. method:: socket.bind(address)
+
+ Bind the socket to *address*. The socket must not already be bound. (The format
+ of *address* depends on the address family --- see above.)
+
+ .. note::
+
+ This method has historically accepted a pair of parameters for :const:`AF_INET`
+ addresses instead of only a tuple. This was never intentional and is no longer
+ available in Python 2.0 and later.
+
+
+.. method:: socket.close()
+
+ Close the socket. All future operations on the socket object will fail. The
+ remote end will receive no more data (after queued data is flushed). Sockets are
+ automatically closed when they are garbage-collected.
+
+
+.. method:: socket.connect(address)
+
+ Connect to a remote socket at *address*. (The format of *address* depends on the
+ address family --- see above.)
+
+ .. note::
+
+ This method has historically accepted a pair of parameters for :const:`AF_INET`
+ addresses instead of only a tuple. This was never intentional and is no longer
+ available in Python 2.0 and later.
+
+
+.. method:: socket.connect_ex(address)
+
+ Like ``connect(address)``, but return an error indicator instead of raising an
+ exception for errors returned by the C-level :cfunc:`connect` call (other
+ problems, such as "host not found," can still raise exceptions). The error
+ indicator is ``0`` if the operation succeeded, otherwise the value of the
+ :cdata:`errno` variable. This is useful to support, for example, asynchronous
+ connects.
+
+ .. note::
+
+ This method has historically accepted a pair of parameters for :const:`AF_INET`
+ addresses instead of only a tuple. This was never intentional and is no longer
+ available in Python 2.0 and later.
+
+
+.. method:: socket.fileno()
+
+ Return the socket's file descriptor (a small integer). This is useful with
+ :func:`select.select`.
+
+ Under Windows the small integer returned by this method cannot be used where a
+ file descriptor can be used (such as :func:`os.fdopen`). Unix does not have
+ this limitation.
+
+
+.. method:: socket.getpeername()
+
+ Return the remote address to which the socket is connected. This is useful to
+ find out the port number of a remote IPv4/v6 socket, for instance. (The format
+ of the address returned depends on the address family --- see above.) On some
+ systems this function is not supported.
+
+
+.. method:: socket.getsockname()
+
+ Return the socket's own address. This is useful to find out the port number of
+ an IPv4/v6 socket, for instance. (The format of the address returned depends on
+ the address family --- see above.)
+
+
+.. method:: socket.getsockopt(level, optname[, buflen])
+
+ Return the value of the given socket option (see the Unix man page
+ :manpage:`getsockopt(2)`). The needed symbolic constants (:const:`SO_\*` etc.)
+ are defined in this module. If *buflen* is absent, an integer option is assumed
+ and its integer value is returned by the function. If *buflen* is present, it
+ specifies the maximum length of the buffer used to receive the option in, and
+ this buffer is returned as a string. It is up to the caller to decode the
+ contents of the buffer (see the optional built-in module :mod:`struct` for a way
+ to decode C structures encoded as strings).
+
+
+.. method:: socket.listen(backlog)
+
+ Listen for connections made to the socket. The *backlog* argument specifies the
+ maximum number of queued connections and should be at least 1; the maximum value
+ is system-dependent (usually 5).
+
+
+.. method:: socket.makefile([mode[, bufsize]])
+
+ .. index:: single: I/O control; buffering
+
+ Return a :dfn:`file object` associated with the socket. (File objects are
+ described in :ref:`bltin-file-objects`.) The file object
+ references a :cfunc:`dup`\ ped version of the socket file descriptor, so the
+ file object and socket object may be closed or garbage-collected independently.
+ The socket must be in blocking mode (it can not have a timeout). The optional
+ *mode* and *bufsize* arguments are interpreted the same way as by the built-in
+ :func:`file` function; see :ref:`built-in-funcs` for more information.
+
+
+.. method:: socket.recv(bufsize[, flags])
+
+ Receive data from the socket. The return value is a string representing the
+ data received. The maximum amount of data to be received at once is specified
+ by *bufsize*. See the Unix manual page :manpage:`recv(2)` for the meaning of
+ the optional argument *flags*; it defaults to zero.
+
+ .. note::
+
+ For best match with hardware and network realities, the value of *bufsize*
+ should be a relatively small power of 2, for example, 4096.
+
+
+.. method:: socket.recvfrom(bufsize[, flags])
+
+ Receive data from the socket. The return value is a pair ``(string, address)``
+ where *string* is a string representing the data received and *address* is the
+ address of the socket sending the data. See the Unix manual page
+ :manpage:`recv(2)` for the meaning of the optional argument *flags*; it defaults
+ to zero. (The format of *address* depends on the address family --- see above.)
+
+
+.. method:: socket.recvfrom_into(buffer[, nbytes[, flags]])
+
+ Receive data from the socket, writing it into *buffer* instead of creating a
+ new string. The return value is a pair ``(nbytes, address)`` where *nbytes* is
+ the number of bytes received and *address* is the address of the socket sending
+ the data. See the Unix manual page :manpage:`recv(2)` for the meaning of the
+ optional argument *flags*; it defaults to zero. (The format of *address*
+ depends on the address family --- see above.)
+
+ .. versionadded:: 2.5
+
+
+.. method:: socket.recv_into(buffer[, nbytes[, flags]])
+
+ Receive up to *nbytes* bytes from the socket, storing the data into a buffer
+ rather than creating a new string. If *nbytes* is not specified (or 0),
+ receive up to the size available in the given buffer. See the Unix manual page
+ :manpage:`recv(2)` for the meaning of the optional argument *flags*; it defaults
+ to zero.
+
+ .. versionadded:: 2.5
+
+
+.. method:: socket.send(string[, flags])
+
+ Send data to the socket. The socket must be connected to a remote socket. The
+ optional *flags* argument has the same meaning as for :meth:`recv` above.
+ Returns the number of bytes sent. Applications are responsible for checking that
+ all data has been sent; if only some of the data was transmitted, the
+ application needs to attempt delivery of the remaining data.
+
+
+.. method:: socket.sendall(string[, flags])
+
+ Send data to the socket. The socket must be connected to a remote socket. The
+ optional *flags* argument has the same meaning as for :meth:`recv` above.
+ Unlike :meth:`send`, this method continues to send data from *string* until
+ either all data has been sent or an error occurs. ``None`` is returned on
+ success. On error, an exception is raised, and there is no way to determine how
+ much data, if any, was successfully sent.
+
+
+.. method:: socket.sendto(string[, flags], address)
+
+ Send data to the socket. The socket should not be connected to a remote socket,
+ since the destination socket is specified by *address*. The optional *flags*
+ argument has the same meaning as for :meth:`recv` above. Return the number of
+ bytes sent. (The format of *address* depends on the address family --- see
+ above.)
+
+
+.. method:: socket.setblocking(flag)
+
+ Set blocking or non-blocking mode of the socket: if *flag* is 0, the socket is
+ set to non-blocking, else to blocking mode. Initially all sockets are in
+ blocking mode. In non-blocking mode, if a :meth:`recv` call doesn't find any
+ data, or if a :meth:`send` call can't immediately dispose of the data, a
+ :exc:`error` exception is raised; in blocking mode, the calls block until they
+ can proceed. ``s.setblocking(0)`` is equivalent to ``s.settimeout(0)``;
+ ``s.setblocking(1)`` is equivalent to ``s.settimeout(None)``.
+
+
+.. method:: socket.settimeout(value)
+
+ Set a timeout on blocking socket operations. The *value* argument can be a
+ nonnegative float expressing seconds, or ``None``. If a float is given,
+ subsequent socket operations will raise an :exc:`timeout` exception if the
+ timeout period *value* has elapsed before the operation has completed. Setting
+ a timeout of ``None`` disables timeouts on socket operations.
+ ``s.settimeout(0.0)`` is equivalent to ``s.setblocking(0)``;
+ ``s.settimeout(None)`` is equivalent to ``s.setblocking(1)``.
+
+ .. versionadded:: 2.3
+
+
+.. method:: socket.gettimeout()
+
+ Return the timeout in floating seconds associated with socket operations, or
+ ``None`` if no timeout is set. This reflects the last call to
+ :meth:`setblocking` or :meth:`settimeout`.
+
+ .. versionadded:: 2.3
+
+Some notes on socket blocking and timeouts: A socket object can be in one of
+three modes: blocking, non-blocking, or timeout. Sockets are always created in
+blocking mode. In blocking mode, operations block until complete. In
+non-blocking mode, operations fail (with an error that is unfortunately
+system-dependent) if they cannot be completed immediately. In timeout mode,
+operations fail if they cannot be completed within the timeout specified for the
+socket. The :meth:`setblocking` method is simply a shorthand for certain
+:meth:`settimeout` calls.
+
+Timeout mode internally sets the socket in non-blocking mode. The blocking and
+timeout modes are shared between file descriptors and socket objects that refer
+to the same network endpoint. A consequence of this is that file objects
+returned by the :meth:`makefile` method must only be used when the socket is in
+blocking mode; in timeout or non-blocking mode file operations that cannot be
+completed immediately will fail.
+
+Note that the :meth:`connect` operation is subject to the timeout setting, and
+in general it is recommended to call :meth:`settimeout` before calling
+:meth:`connect`.
+
+
+.. method:: socket.setsockopt(level, optname, value)
+
+ .. index:: module: struct
+
+ Set the value of the given socket option (see the Unix manual page
+ :manpage:`setsockopt(2)`). The needed symbolic constants are defined in the
+ :mod:`socket` module (:const:`SO_\*` etc.). The value can be an integer or a
+ string representing a buffer. In the latter case it is up to the caller to
+ ensure that the string contains the proper bits (see the optional built-in
+ module :mod:`struct` for a way to encode C structures as strings).
+
+
+.. method:: socket.shutdown(how)
+
+ Shut down one or both halves of the connection. If *how* is :const:`SHUT_RD`,
+ further receives are disallowed. If *how* is :const:`SHUT_WR`, further sends
+ are disallowed. If *how* is :const:`SHUT_RDWR`, further sends and receives are
+ disallowed.
+
+Note that there are no methods :meth:`read` or :meth:`write`; use :meth:`recv`
+and :meth:`send` without *flags* argument instead.
+
+Socket objects also have these (read-only) attributes that correspond to the
+values given to the :class:`socket` constructor.
+
+
+.. attribute:: socket.family
+
+ The socket family.
+
+ .. versionadded:: 2.5
+
+
+.. attribute:: socket.type
+
+ The socket type.
+
+ .. versionadded:: 2.5
+
+
+.. attribute:: socket.proto
+
+ The socket protocol.
+
+ .. versionadded:: 2.5
+
+
+.. _ssl-objects:
+
+SSL Objects
+-----------
+
+SSL objects have the following methods.
+
+
+.. method:: SSL.write(s)
+
+ Writes the string *s* to the on the object's SSL connection. The return value is
+ the number of bytes written.
+
+
+.. method:: SSL.read([n])
+
+ If *n* is provided, read *n* bytes from the SSL connection, otherwise read until
+ EOF. The return value is a string of the bytes read.
+
+
+.. method:: SSL.server()
+
+ Returns a string describing the server's certificate. Useful for debugging
+ purposes; do not parse the content of this string because its format can't be
+ parsed unambiguously.
+
+
+.. method:: SSL.issuer()
+
+ Returns a string describing the issuer of the server's certificate. Useful for
+ debugging purposes; do not parse the content of this string because its format
+ can't be parsed unambiguously.
+
+
+.. _socket-example:
+
+Example
+-------
+
+Here are four minimal example programs using the TCP/IP protocol: a server that
+echoes all data that it receives back (servicing only one client), and a client
+using it. Note that a server must perform the sequence :func:`socket`,
+:meth:`bind`, :meth:`listen`, :meth:`accept` (possibly repeating the
+:meth:`accept` to service more than one client), while a client only needs the
+sequence :func:`socket`, :meth:`connect`. Also note that the server does not
+:meth:`send`/:meth:`recv` on the socket it is listening on but on the new
+socket returned by :meth:`accept`.
+
+The first two examples support IPv4 only. ::
+
+ # Echo server program
+ import socket
+
+ HOST = '' # Symbolic name meaning the local host
+ PORT = 50007 # Arbitrary non-privileged port
+ s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ s.bind((HOST, PORT))
+ s.listen(1)
+ conn, addr = s.accept()
+ print 'Connected by', addr
+ while 1:
+ data = conn.recv(1024)
+ if not data: break
+ conn.send(data)
+ conn.close()
+
+::
+
+ # Echo client program
+ import socket
+
+ HOST = 'daring.cwi.nl' # The remote host
+ PORT = 50007 # The same port as used by the server
+ s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ s.connect((HOST, PORT))
+ s.send('Hello, world')
+ data = s.recv(1024)
+ s.close()
+ print 'Received', repr(data)
+
+The next two examples are identical to the above two, but support both IPv4 and
+IPv6. The server side will listen to the first address family available (it
+should listen to both instead). On most of IPv6-ready systems, IPv6 will take
+precedence and the server may not accept IPv4 traffic. The client side will try
+to connect to the all addresses returned as a result of the name resolution, and
+sends traffic to the first one connected successfully. ::
+
+ # Echo server program
+ import socket
+ import sys
+
+ HOST = '' # Symbolic name meaning the local host
+ PORT = 50007 # Arbitrary non-privileged port
+ s = None
+ for res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC, socket.SOCK_STREAM, 0, socket.AI_PASSIVE):
+ af, socktype, proto, canonname, sa = res
+ try:
+ s = socket.socket(af, socktype, proto)
+ except socket.error as msg:
+ s = None
+ continue
+ try:
+ s.bind(sa)
+ s.listen(1)
+ except socket.error as msg:
+ s.close()
+ s = None
+ continue
+ break
+ if s is None:
+ print 'could not open socket'
+ sys.exit(1)
+ conn, addr = s.accept()
+ print 'Connected by', addr
+ while 1:
+ data = conn.recv(1024)
+ if not data: break
+ conn.send(data)
+ conn.close()
+
+::
+
+ # Echo client program
+ import socket
+ import sys
+
+ HOST = 'daring.cwi.nl' # The remote host
+ PORT = 50007 # The same port as used by the server
+ s = None
+ for res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC, socket.SOCK_STREAM):
+ af, socktype, proto, canonname, sa = res
+ try:
+ s = socket.socket(af, socktype, proto)
+ except socket.error as msg:
+ s = None
+ continue
+ try:
+ s.connect(sa)
+ except socket.error as msg:
+ s.close()
+ s = None
+ continue
+ break
+ if s is None:
+ print 'could not open socket'
+ sys.exit(1)
+ s.send('Hello, world')
+ data = s.recv(1024)
+ s.close()
+ print 'Received', repr(data)
+
+This example connects to an SSL server, prints the server and issuer's
+distinguished names, sends some bytes, and reads part of the response::
+
+ import socket
+
+ s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ s.connect(('www.verisign.com', 443))
+
+ ssl_sock = socket.ssl(s)
+
+ print repr(ssl_sock.server())
+ print repr(ssl_sock.issuer())
+
+ # Set a simple HTTP request -- use httplib in actual code.
+ ssl_sock.write("""GET / HTTP/1.0\r
+ Host: www.verisign.com\r\n\r\n""")
+
+ # Read a chunk of data. Will not necessarily
+ # read all the data returned by the server.
+ data = ssl_sock.read()
+
+ # Note that you need to close the underlying socket, not the SSL object.
+ del ssl_sock
+ s.close()
+
+At this writing, this SSL example prints the following output (line breaks
+inserted for readability)::
+
+ '/C=US/ST=California/L=Mountain View/
+ O=VeriSign, Inc./OU=Production Services/
+ OU=Terms of use at www.verisign.com/rpa (c)00/
+ CN=www.verisign.com'
+ '/O=VeriSign Trust Network/OU=VeriSign, Inc./
+ OU=VeriSign International Server CA - Class 3/
+ OU=www.verisign.com/CPS Incorp.by Ref. LIABILITY LTD.(c)97 VeriSign'
+
diff --git a/Doc/library/socketserver.rst b/Doc/library/socketserver.rst
new file mode 100644
index 0000000000..96fae6bfe6
--- /dev/null
+++ b/Doc/library/socketserver.rst
@@ -0,0 +1,295 @@
+
+:mod:`SocketServer` --- A framework for network servers
+=======================================================
+
+.. module:: SocketServer
+ :synopsis: A framework for network servers.
+
+
+The :mod:`SocketServer` module simplifies the task of writing network servers.
+
+There are four basic server classes: :class:`TCPServer` uses the Internet TCP
+protocol, which provides for continuous streams of data between the client and
+server. :class:`UDPServer` uses datagrams, which are discrete packets of
+information that may arrive out of order or be lost while in transit. The more
+infrequently used :class:`UnixStreamServer` and :class:`UnixDatagramServer`
+classes are similar, but use Unix domain sockets; they're not available on
+non-Unix platforms. For more details on network programming, consult a book
+such as
+W. Richard Steven's UNIX Network Programming or Ralph Davis's Win32 Network
+Programming.
+
+These four classes process requests :dfn:`synchronously`; each request must be
+completed before the next request can be started. This isn't suitable if each
+request takes a long time to complete, because it requires a lot of computation,
+or because it returns a lot of data which the client is slow to process. The
+solution is to create a separate process or thread to handle each request; the
+:class:`ForkingMixIn` and :class:`ThreadingMixIn` mix-in classes can be used to
+support asynchronous behaviour.
+
+Creating a server requires several steps. First, you must create a request
+handler class by subclassing the :class:`BaseRequestHandler` class and
+overriding its :meth:`handle` method; this method will process incoming
+requests. Second, you must instantiate one of the server classes, passing it
+the server's address and the request handler class. Finally, call the
+:meth:`handle_request` or :meth:`serve_forever` method of the server object to
+process one or many requests.
+
+When inheriting from :class:`ThreadingMixIn` for threaded connection behavior,
+you should explicitly declare how you want your threads to behave on an abrupt
+shutdown. The :class:`ThreadingMixIn` class defines an attribute
+*daemon_threads*, which indicates whether or not the server should wait for
+thread termination. You should set the flag explicitly if you would like threads
+to behave autonomously; the default is :const:`False`, meaning that Python will
+not exit until all threads created by :class:`ThreadingMixIn` have exited.
+
+Server classes have the same external methods and attributes, no matter what
+network protocol they use:
+
+
+Server Creation Notes
+---------------------
+
+There are five classes in an inheritance diagram, four of which represent
+synchronous servers of four types::
+
+ +------------+
+ | BaseServer |
+ +------------+
+ |
+ v
+ +-----------+ +------------------+
+ | TCPServer |------->| UnixStreamServer |
+ +-----------+ +------------------+
+ |
+ v
+ +-----------+ +--------------------+
+ | UDPServer |------->| UnixDatagramServer |
+ +-----------+ +--------------------+
+
+Note that :class:`UnixDatagramServer` derives from :class:`UDPServer`, not from
+:class:`UnixStreamServer` --- the only difference between an IP and a Unix
+stream server is the address family, which is simply repeated in both Unix
+server classes.
+
+Forking and threading versions of each type of server can be created using the
+:class:`ForkingMixIn` and :class:`ThreadingMixIn` mix-in classes. For instance,
+a threading UDP server class is created as follows::
+
+ class ThreadingUDPServer(ThreadingMixIn, UDPServer): pass
+
+The mix-in class must come first, since it overrides a method defined in
+:class:`UDPServer`. Setting the various member variables also changes the
+behavior of the underlying server mechanism.
+
+To implement a service, you must derive a class from :class:`BaseRequestHandler`
+and redefine its :meth:`handle` method. You can then run various versions of
+the service by combining one of the server classes with your request handler
+class. The request handler class must be different for datagram or stream
+services. This can be hidden by using the handler subclasses
+:class:`StreamRequestHandler` or :class:`DatagramRequestHandler`.
+
+Of course, you still have to use your head! For instance, it makes no sense to
+use a forking server if the service contains state in memory that can be
+modified by different requests, since the modifications in the child process
+would never reach the initial state kept in the parent process and passed to
+each child. In this case, you can use a threading server, but you will probably
+have to use locks to protect the integrity of the shared data.
+
+On the other hand, if you are building an HTTP server where all data is stored
+externally (for instance, in the file system), a synchronous class will
+essentially render the service "deaf" while one request is being handled --
+which may be for a very long time if a client is slow to receive all the data it
+has requested. Here a threading or forking server is appropriate.
+
+In some cases, it may be appropriate to process part of a request synchronously,
+but to finish processing in a forked child depending on the request data. This
+can be implemented by using a synchronous server and doing an explicit fork in
+the request handler class :meth:`handle` method.
+
+Another approach to handling multiple simultaneous requests in an environment
+that supports neither threads nor :func:`fork` (or where these are too expensive
+or inappropriate for the service) is to maintain an explicit table of partially
+finished requests and to use :func:`select` to decide which request to work on
+next (or whether to handle a new incoming request). This is particularly
+important for stream services where each client can potentially be connected for
+a long time (if threads or subprocesses cannot be used).
+
+.. % XXX should data and methods be intermingled, or separate?
+.. % how should the distinction between class and instance variables be
+.. % drawn?
+
+
+Server Objects
+--------------
+
+
+.. function:: fileno()
+
+ Return an integer file descriptor for the socket on which the server is
+ listening. This function is most commonly passed to :func:`select.select`, to
+ allow monitoring multiple servers in the same process.
+
+
+.. function:: handle_request()
+
+ Process a single request. This function calls the following methods in order:
+ :meth:`get_request`, :meth:`verify_request`, and :meth:`process_request`. If
+ the user-provided :meth:`handle` method of the handler class raises an
+ exception, the server's :meth:`handle_error` method will be called.
+
+
+.. function:: serve_forever()
+
+ Handle an infinite number of requests. This simply calls :meth:`handle_request`
+ inside an infinite loop.
+
+
+.. data:: address_family
+
+ The family of protocols to which the server's socket belongs.
+ :const:`socket.AF_INET` and :const:`socket.AF_UNIX` are two possible values.
+
+
+.. data:: RequestHandlerClass
+
+ The user-provided request handler class; an instance of this class is created
+ for each request.
+
+
+.. data:: server_address
+
+ The address on which the server is listening. The format of addresses varies
+ depending on the protocol family; see the documentation for the socket module
+ for details. For Internet protocols, this is a tuple containing a string giving
+ the address, and an integer port number: ``('127.0.0.1', 80)``, for example.
+
+
+.. data:: socket
+
+ The socket object on which the server will listen for incoming requests.
+
+The server classes support the following class variables:
+
+.. % XXX should class variables be covered before instance variables, or
+.. % vice versa?
+
+
+.. data:: allow_reuse_address
+
+ Whether the server will allow the reuse of an address. This defaults to
+ :const:`False`, and can be set in subclasses to change the policy.
+
+
+.. data:: request_queue_size
+
+ The size of the request queue. If it takes a long time to process a single
+ request, any requests that arrive while the server is busy are placed into a
+ queue, up to :attr:`request_queue_size` requests. Once the queue is full,
+ further requests from clients will get a "Connection denied" error. The default
+ value is usually 5, but this can be overridden by subclasses.
+
+
+.. data:: socket_type
+
+ The type of socket used by the server; :const:`socket.SOCK_STREAM` and
+ :const:`socket.SOCK_DGRAM` are two possible values.
+
+There are various server methods that can be overridden by subclasses of base
+server classes like :class:`TCPServer`; these methods aren't useful to external
+users of the server object.
+
+.. % should the default implementations of these be documented, or should
+.. % it be assumed that the user will look at SocketServer.py?
+
+
+.. function:: finish_request()
+
+ Actually processes the request by instantiating :attr:`RequestHandlerClass` and
+ calling its :meth:`handle` method.
+
+
+.. function:: get_request()
+
+ Must accept a request from the socket, and return a 2-tuple containing the *new*
+ socket object to be used to communicate with the client, and the client's
+ address.
+
+
+.. function:: handle_error(request, client_address)
+
+ This function is called if the :attr:`RequestHandlerClass`'s :meth:`handle`
+ method raises an exception. The default action is to print the traceback to
+ standard output and continue handling further requests.
+
+
+.. function:: process_request(request, client_address)
+
+ Calls :meth:`finish_request` to create an instance of the
+ :attr:`RequestHandlerClass`. If desired, this function can create a new process
+ or thread to handle the request; the :class:`ForkingMixIn` and
+ :class:`ThreadingMixIn` classes do this.
+
+.. % Is there any point in documenting the following two functions?
+.. % What would the purpose of overriding them be: initializing server
+.. % instance variables, adding new network families?
+
+
+.. function:: server_activate()
+
+ Called by the server's constructor to activate the server. The default behavior
+ just :meth:`listen`\ s to the server's socket. May be overridden.
+
+
+.. function:: server_bind()
+
+ Called by the server's constructor to bind the socket to the desired address.
+ May be overridden.
+
+
+.. function:: verify_request(request, client_address)
+
+ Must return a Boolean value; if the value is :const:`True`, the request will be
+ processed, and if it's :const:`False`, the request will be denied. This function
+ can be overridden to implement access controls for a server. The default
+ implementation always returns :const:`True`.
+
+
+RequestHandler Objects
+----------------------
+
+The request handler class must define a new :meth:`handle` method, and can
+override any of the following methods. A new instance is created for each
+request.
+
+
+.. function:: finish()
+
+ Called after the :meth:`handle` method to perform any clean-up actions required.
+ The default implementation does nothing. If :meth:`setup` or :meth:`handle`
+ raise an exception, this function will not be called.
+
+
+.. function:: handle()
+
+ This function must do all the work required to service a request. The default
+ implementation does nothing. Several instance attributes are available to it;
+ the request is available as :attr:`self.request`; the client address as
+ :attr:`self.client_address`; and the server instance as :attr:`self.server`, in
+ case it needs access to per-server information.
+
+ The type of :attr:`self.request` is different for datagram or stream services.
+ For stream services, :attr:`self.request` is a socket object; for datagram
+ services, :attr:`self.request` is a string. However, this can be hidden by using
+ the request handler subclasses :class:`StreamRequestHandler` or
+ :class:`DatagramRequestHandler`, which override the :meth:`setup` and
+ :meth:`finish` methods, and provide :attr:`self.rfile` and :attr:`self.wfile`
+ attributes. :attr:`self.rfile` and :attr:`self.wfile` can be read or written,
+ respectively, to get the request data or return data to the client.
+
+
+.. function:: setup()
+
+ Called before the :meth:`handle` method to perform any initialization actions
+ required. The default implementation does nothing.
+
diff --git a/Doc/library/someos.rst b/Doc/library/someos.rst
new file mode 100644
index 0000000000..5ee96bc35b
--- /dev/null
+++ b/Doc/library/someos.rst
@@ -0,0 +1,23 @@
+
+.. _someos:
+
+**********************************
+Optional Operating System Services
+**********************************
+
+The modules described in this chapter provide interfaces to operating system
+features that are available on selected operating systems only. The interfaces
+are generally modeled after the Unix or C interfaces but they are available on
+some other systems as well (e.g. Windows or NT). Here's an overview:
+
+
+.. toctree::
+
+ select.rst
+ thread.rst
+ threading.rst
+ dummy_thread.rst
+ dummy_threading.rst
+ mmap.rst
+ readline.rst
+ rlcompleter.rst
diff --git a/Doc/library/spwd.rst b/Doc/library/spwd.rst
new file mode 100644
index 0000000000..6cbe925b25
--- /dev/null
+++ b/Doc/library/spwd.rst
@@ -0,0 +1,74 @@
+
+:mod:`spwd` --- The shadow password database
+============================================
+
+.. module:: spwd
+ :platform: Unix
+ :synopsis: The shadow password database (getspnam() and friends).
+
+
+.. versionadded:: 2.5
+
+This module provides access to the Unix shadow password database. It is
+available on various Unix versions.
+
+You must have enough privileges to access the shadow password database (this
+usually means you have to be root).
+
+Shadow password database entries are reported as a tuple-like object, whose
+attributes correspond to the members of the ``spwd`` structure (Attribute field
+below, see ``<shadow.h>``):
+
++-------+---------------+---------------------------------+
+| Index | Attribute | Meaning |
++=======+===============+=================================+
+| 0 | ``sp_nam`` | Login name |
++-------+---------------+---------------------------------+
+| 1 | ``sp_pwd`` | Encrypted password |
++-------+---------------+---------------------------------+
+| 2 | ``sp_lstchg`` | Date of last change |
++-------+---------------+---------------------------------+
+| 3 | ``sp_min`` | Minimal number of days between |
+| | | changes |
++-------+---------------+---------------------------------+
+| 4 | ``sp_max`` | Maximum number of days between |
+| | | changes |
++-------+---------------+---------------------------------+
+| 5 | ``sp_warn`` | Number of days before password |
+| | | expires to warn user about it |
++-------+---------------+---------------------------------+
+| 6 | ``sp_inact`` | Number of days after password |
+| | | expires until account is |
+| | | blocked |
++-------+---------------+---------------------------------+
+| 7 | ``sp_expire`` | Number of days since 1970-01-01 |
+| | | until account is disabled |
++-------+---------------+---------------------------------+
+| 8 | ``sp_flag`` | Reserved |
++-------+---------------+---------------------------------+
+
+The sp_nam and sp_pwd items are strings, all others are integers.
+:exc:`KeyError` is raised if the entry asked for cannot be found.
+
+It defines the following items:
+
+
+.. function:: getspnam(name)
+
+ Return the shadow password database entry for the given user name.
+
+
+.. function:: getspall()
+
+ Return a list of all available shadow password database entries, in arbitrary
+ order.
+
+
+.. seealso::
+
+ Module :mod:`grp`
+ An interface to the group database, similar to this.
+
+ Module :mod:`pwd`
+ An interface to the normal password database, similar to this.
+
diff --git a/Doc/library/sqlite3.rst b/Doc/library/sqlite3.rst
new file mode 100644
index 0000000000..707092b027
--- /dev/null
+++ b/Doc/library/sqlite3.rst
@@ -0,0 +1,689 @@
+
+:mod:`sqlite3` --- DB-API 2.0 interface for SQLite databases
+============================================================
+
+.. module:: sqlite3
+ :synopsis: A DB-API 2.0 implementation using SQLite 3.x.
+.. sectionauthor:: Gerhard Häring <gh@ghaering.de>
+
+
+.. versionadded:: 2.5
+
+SQLite is a C library that provides a lightweight disk-based database that
+doesn't require a separate server process and allows accessing the database
+using a nonstandard variant of the SQL query language. Some applications can use
+SQLite for internal data storage. It's also possible to prototype an
+application using SQLite and then port the code to a larger database such as
+PostgreSQL or Oracle.
+
+pysqlite was written by Gerhard Häring and provides a SQL interface compliant
+with the DB-API 2.0 specification described by :pep:`249`.
+
+To use the module, you must first create a :class:`Connection` object that
+represents the database. Here the data will be stored in the
+:file:`/tmp/example` file::
+
+ conn = sqlite3.connect('/tmp/example')
+
+You can also supply the special name ``:memory:`` to create a database in RAM.
+
+Once you have a :class:`Connection`, you can create a :class:`Cursor` object
+and call its :meth:`execute` method to perform SQL commands::
+
+ c = conn.cursor()
+
+ # Create table
+ c.execute('''create table stocks
+ (date text, trans text, symbol text,
+ qty real, price real)''')
+
+ # Insert a row of data
+ c.execute("""insert into stocks
+ values ('2006-01-05','BUY','RHAT',100,35.14)""")
+
+ # Save (commit) the changes
+ conn.commit()
+
+ # We can also close the cursor if we are done with it
+ c.close()
+
+Usually your SQL operations will need to use values from Python variables. You
+shouldn't assemble your query using Python's string operations because doing so
+is insecure; it makes your program vulnerable to an SQL injection attack.
+
+Instead, use the DB-API's parameter substitution. Put ``?`` as a placeholder
+wherever you want to use a value, and then provide a tuple of values as the
+second argument to the cursor's :meth:`execute` method. (Other database modules
+may use a different placeholder, such as ``%s`` or ``:1``.) For example::
+
+ # Never do this -- insecure!
+ symbol = 'IBM'
+ c.execute("... where symbol = '%s'" % symbol)
+
+ # Do this instead
+ t = (symbol,)
+ c.execute('select * from stocks where symbol=?', t)
+
+ # Larger example
+ for t in (('2006-03-28', 'BUY', 'IBM', 1000, 45.00),
+ ('2006-04-05', 'BUY', 'MSOFT', 1000, 72.00),
+ ('2006-04-06', 'SELL', 'IBM', 500, 53.00),
+ ):
+ c.execute('insert into stocks values (?,?,?,?,?)', t)
+
+To retrieve data after executing a SELECT statement, you can either treat the
+cursor as an iterator, call the cursor's :meth:`fetchone` method to retrieve a
+single matching row, or call :meth:`fetchall` to get a list of the matching
+rows.
+
+This example uses the iterator form::
+
+ >>> c = conn.cursor()
+ >>> c.execute('select * from stocks order by price')
+ >>> for row in c:
+ ... print row
+ ...
+ (u'2006-01-05', u'BUY', u'RHAT', 100, 35.140000000000001)
+ (u'2006-03-28', u'BUY', u'IBM', 1000, 45.0)
+ (u'2006-04-06', u'SELL', u'IBM', 500, 53.0)
+ (u'2006-04-05', u'BUY', u'MSOFT', 1000, 72.0)
+ >>>
+
+
+.. seealso::
+
+ http://www.pysqlite.org
+ The pysqlite web page.
+
+ http://www.sqlite.org
+ The SQLite web page; the documentation describes the syntax and the available
+ data types for the supported SQL dialect.
+
+ :pep:`249` - Database API Specification 2.0
+ PEP written by Marc-André Lemburg.
+
+
+.. _sqlite3-module-contents:
+
+Module functions and constants
+------------------------------
+
+
+.. data:: PARSE_DECLTYPES
+
+ This constant is meant to be used with the *detect_types* parameter of the
+ :func:`connect` function.
+
+ Setting it makes the :mod:`sqlite3` module parse the declared type for each
+ column it returns. It will parse out the first word of the declared type, i. e.
+ for "integer primary key", it will parse out "integer". Then for that column, it
+ will look into the converters dictionary and use the converter function
+ registered for that type there. Converter names are case-sensitive!
+
+
+.. data:: PARSE_COLNAMES
+
+ This constant is meant to be used with the *detect_types* parameter of the
+ :func:`connect` function.
+
+ Setting this makes the SQLite interface parse the column name for each column it
+ returns. It will look for a string formed [mytype] in there, and then decide
+ that 'mytype' is the type of the column. It will try to find an entry of
+ 'mytype' in the converters dictionary and then use the converter function found
+ there to return the value. The column name found in :attr:`cursor.description`
+ is only the first word of the column name, i. e. if you use something like
+ ``'as "x [datetime]"'`` in your SQL, then we will parse out everything until the
+ first blank for the column name: the column name would simply be "x".
+
+
+.. function:: connect(database[, timeout, isolation_level, detect_types, factory])
+
+ Opens a connection to the SQLite database file *database*. You can use
+ ``":memory:"`` to open a database connection to a database that resides in RAM
+ instead of on disk.
+
+ When a database is accessed by multiple connections, and one of the processes
+ modifies the database, the SQLite database is locked until that transaction is
+ committed. The *timeout* parameter specifies how long the connection should wait
+ for the lock to go away until raising an exception. The default for the timeout
+ parameter is 5.0 (five seconds).
+
+ For the *isolation_level* parameter, please see the
+ :attr:`Connection.isolation_level` property of :class:`Connection` objects.
+
+ SQLite natively supports only the types TEXT, INTEGER, FLOAT, BLOB and NULL. If
+ you want to use other types you must add support for them yourself. The
+ *detect_types* parameter and the using custom **converters** registered with the
+ module-level :func:`register_converter` function allow you to easily do that.
+
+ *detect_types* defaults to 0 (i. e. off, no type detection), you can set it to
+ any combination of :const:`PARSE_DECLTYPES` and :const:`PARSE_COLNAMES` to turn
+ type detection on.
+
+ By default, the :mod:`sqlite3` module uses its :class:`Connection` class for the
+ connect call. You can, however, subclass the :class:`Connection` class and make
+ :func:`connect` use your class instead by providing your class for the *factory*
+ parameter.
+
+ Consult the section :ref:`sqlite3-types` of this manual for details.
+
+ The :mod:`sqlite3` module internally uses a statement cache to avoid SQL parsing
+ overhead. If you want to explicitly set the number of statements that are cached
+ for the connection, you can set the *cached_statements* parameter. The currently
+ implemented default is to cache 100 statements.
+
+
+.. function:: register_converter(typename, callable)
+
+ Registers a callable to convert a bytestring from the database into a custom
+ Python type. The callable will be invoked for all database values that are of
+ the type *typename*. Confer the parameter *detect_types* of the :func:`connect`
+ function for how the type detection works. Note that the case of *typename* and
+ the name of the type in your query must match!
+
+
+.. function:: register_adapter(type, callable)
+
+ Registers a callable to convert the custom Python type *type* into one of
+ SQLite's supported types. The callable *callable* accepts as single parameter
+ the Python value, and must return a value of the following types: int, long,
+ float, str (UTF-8 encoded), unicode or buffer.
+
+
+.. function:: complete_statement(sql)
+
+ Returns :const:`True` if the string *sql* contains one or more complete SQL
+ statements terminated by semicolons. It does not verify that the SQL is
+ syntactically correct, only that there are no unclosed string literals and the
+ statement is terminated by a semicolon.
+
+ This can be used to build a shell for SQLite, as in the following example:
+
+
+ .. literalinclude:: ../includes/sqlite3/complete_statement.py
+
+
+.. function:: enable_callback_tracebacks(flag)
+
+ By default you will not get any tracebacks in user-defined functions,
+ aggregates, converters, authorizer callbacks etc. If you want to debug them, you
+ can call this function with *flag* as True. Afterwards, you will get tracebacks
+ from callbacks on ``sys.stderr``. Use :const:`False` to disable the feature
+ again.
+
+
+.. _sqlite3-connection-objects:
+
+Connection Objects
+------------------
+
+A :class:`Connection` instance has the following attributes and methods:
+
+.. attribute:: Connection.isolation_level
+
+ Get or set the current isolation level. None for autocommit mode or one of
+ "DEFERRED", "IMMEDIATE" or "EXLUSIVE". See section
+ :ref:`sqlite3-controlling-transactions` for a more detailed explanation.
+
+
+.. method:: Connection.cursor([cursorClass])
+
+ The cursor method accepts a single optional parameter *cursorClass*. If
+ supplied, this must be a custom cursor class that extends
+ :class:`sqlite3.Cursor`.
+
+
+.. method:: Connection.execute(sql, [parameters])
+
+ This is a nonstandard shortcut that creates an intermediate cursor object by
+ calling the cursor method, then calls the cursor's :meth:`execute` method with
+ the parameters given.
+
+
+.. method:: Connection.executemany(sql, [parameters])
+
+ This is a nonstandard shortcut that creates an intermediate cursor object by
+ calling the cursor method, then calls the cursor's :meth:`executemany` method
+ with the parameters given.
+
+
+.. method:: Connection.executescript(sql_script)
+
+ This is a nonstandard shortcut that creates an intermediate cursor object by
+ calling the cursor method, then calls the cursor's :meth:`executescript` method
+ with the parameters given.
+
+
+.. method:: Connection.create_function(name, num_params, func)
+
+ Creates a user-defined function that you can later use from within SQL
+ statements under the function name *name*. *num_params* is the number of
+ parameters the function accepts, and *func* is a Python callable that is called
+ as the SQL function.
+
+ The function can return any of the types supported by SQLite: unicode, str, int,
+ long, float, buffer and None.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/md5func.py
+
+
+.. method:: Connection.create_aggregate(name, num_params, aggregate_class)
+
+ Creates a user-defined aggregate function.
+
+ The aggregate class must implement a ``step`` method, which accepts the number
+ of parameters *num_params*, and a ``finalize`` method which will return the
+ final result of the aggregate.
+
+ The ``finalize`` method can return any of the types supported by SQLite:
+ unicode, str, int, long, float, buffer and None.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/mysumaggr.py
+
+
+.. method:: Connection.create_collation(name, callable)
+
+ Creates a collation with the specified *name* and *callable*. The callable will
+ be passed two string arguments. It should return -1 if the first is ordered
+ lower than the second, 0 if they are ordered equal and 1 if the first is ordered
+ higher than the second. Note that this controls sorting (ORDER BY in SQL) so
+ your comparisons don't affect other SQL operations.
+
+ Note that the callable will get its parameters as Python bytestrings, which will
+ normally be encoded in UTF-8.
+
+ The following example shows a custom collation that sorts "the wrong way":
+
+ .. literalinclude:: ../includes/sqlite3/collation_reverse.py
+
+ To remove a collation, call ``create_collation`` with None as callable::
+
+ con.create_collation("reverse", None)
+
+
+.. method:: Connection.interrupt()
+
+ You can call this method from a different thread to abort any queries that might
+ be executing on the connection. The query will then abort and the caller will
+ get an exception.
+
+
+.. method:: Connection.set_authorizer(authorizer_callback)
+
+ This routine registers a callback. The callback is invoked for each attempt to
+ access a column of a table in the database. The callback should return
+ :const:`SQLITE_OK` if access is allowed, :const:`SQLITE_DENY` if the entire SQL
+ statement should be aborted with an error and :const:`SQLITE_IGNORE` if the
+ column should be treated as a NULL value. These constants are available in the
+ :mod:`sqlite3` module.
+
+ The first argument to the callback signifies what kind of operation is to be
+ authorized. The second and third argument will be arguments or :const:`None`
+ depending on the first argument. The 4th argument is the name of the database
+ ("main", "temp", etc.) if applicable. The 5th argument is the name of the
+ inner-most trigger or view that is responsible for the access attempt or
+ :const:`None` if this access attempt is directly from input SQL code.
+
+ Please consult the SQLite documentation about the possible values for the first
+ argument and the meaning of the second and third argument depending on the first
+ one. All necessary constants are available in the :mod:`sqlite3` module.
+
+
+.. attribute:: Connection.row_factory
+
+ You can change this attribute to a callable that accepts the cursor and the
+ original row as a tuple and will return the real result row. This way, you can
+ implement more advanced ways of returning results, such as returning an object
+ that can also access columns by name.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/row_factory.py
+
+ If returning a tuple doesn't suffice and you want name-based access to
+ columns, you should consider setting :attr:`row_factory` to the
+ highly-optimized :class:`sqlite3.Row` type. :class:`Row` provides both
+ index-based and case-insensitive name-based access to columns with almost no
+ memory overhead. It will probably be better than your own custom
+ dictionary-based approach or even a db_row based solution.
+
+ .. % XXX what's a db_row-based solution?
+
+
+.. attribute:: Connection.text_factory
+
+ Using this attribute you can control what objects are returned for the TEXT data
+ type. By default, this attribute is set to :class:`unicode` and the
+ :mod:`sqlite3` module will return Unicode objects for TEXT. If you want to
+ return bytestrings instead, you can set it to :class:`str`.
+
+ For efficiency reasons, there's also a way to return Unicode objects only for
+ non-ASCII data, and bytestrings otherwise. To activate it, set this attribute to
+ :const:`sqlite3.OptimizedUnicode`.
+
+ You can also set it to any other callable that accepts a single bytestring
+ parameter and returns the resulting object.
+
+ See the following example code for illustration:
+
+ .. literalinclude:: ../includes/sqlite3/text_factory.py
+
+
+.. attribute:: Connection.total_changes
+
+ Returns the total number of database rows that have been modified, inserted, or
+ deleted since the database connection was opened.
+
+
+.. _sqlite3-cursor-objects:
+
+Cursor Objects
+--------------
+
+A :class:`Cursor` instance has the following attributes and methods:
+
+
+.. method:: Cursor.execute(sql, [parameters])
+
+ Executes a SQL statement. The SQL statement may be parametrized (i. e.
+ placeholders instead of SQL literals). The :mod:`sqlite3` module supports two
+ kinds of placeholders: question marks (qmark style) and named placeholders
+ (named style).
+
+ This example shows how to use parameters with qmark style:
+
+ .. literalinclude:: ../includes/sqlite3/execute_1.py
+
+ This example shows how to use the named style:
+
+ .. literalinclude:: ../includes/sqlite3/execute_2.py
+
+ :meth:`execute` will only execute a single SQL statement. If you try to execute
+ more than one statement with it, it will raise a Warning. Use
+ :meth:`executescript` if you want to execute multiple SQL statements with one
+ call.
+
+
+.. method:: Cursor.executemany(sql, seq_of_parameters)
+
+ Executes a SQL command against all parameter sequences or mappings found in the
+ sequence *sql*. The :mod:`sqlite3` module also allows using an iterator yielding
+ parameters instead of a sequence.
+
+ .. literalinclude:: ../includes/sqlite3/executemany_1.py
+
+ Here's a shorter example using a generator:
+
+ .. literalinclude:: ../includes/sqlite3/executemany_2.py
+
+
+.. method:: Cursor.executescript(sql_script)
+
+ This is a nonstandard convenience method for executing multiple SQL statements
+ at once. It issues a COMMIT statement first, then executes the SQL script it
+ gets as a parameter.
+
+ *sql_script* can be a bytestring or a Unicode string.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/executescript.py
+
+
+.. attribute:: Cursor.rowcount
+
+ Although the :class:`Cursor` class of the :mod:`sqlite3` module implements this
+ attribute, the database engine's own support for the determination of "rows
+ affected"/"rows selected" is quirky.
+
+ For ``SELECT`` statements, :attr:`rowcount` is always None because we cannot
+ determine the number of rows a query produced until all rows were fetched.
+
+ For ``DELETE`` statements, SQLite reports :attr:`rowcount` as 0 if you make a
+ ``DELETE FROM table`` without any condition.
+
+ For :meth:`executemany` statements, the number of modifications are summed up
+ into :attr:`rowcount`.
+
+ As required by the Python DB API Spec, the :attr:`rowcount` attribute "is -1 in
+ case no executeXX() has been performed on the cursor or the rowcount of the last
+ operation is not determinable by the interface".
+
+
+.. _sqlite3-types:
+
+SQLite and Python types
+-----------------------
+
+
+Introduction
+^^^^^^^^^^^^
+
+SQLite natively supports the following types: NULL, INTEGER, REAL, TEXT, BLOB.
+
+The following Python types can thus be sent to SQLite without any problem:
+
++------------------------+-------------+
+| Python type | SQLite type |
++========================+=============+
+| ``None`` | NULL |
++------------------------+-------------+
+| ``int`` | INTEGER |
++------------------------+-------------+
+| ``long`` | INTEGER |
++------------------------+-------------+
+| ``float`` | REAL |
++------------------------+-------------+
+| ``str (UTF8-encoded)`` | TEXT |
++------------------------+-------------+
+| ``unicode`` | TEXT |
++------------------------+-------------+
+| ``buffer`` | BLOB |
++------------------------+-------------+
+
+This is how SQLite types are converted to Python types by default:
+
++-------------+---------------------------------------------+
+| SQLite type | Python type |
++=============+=============================================+
+| ``NULL`` | None |
++-------------+---------------------------------------------+
+| ``INTEGER`` | int or long, depending on size |
++-------------+---------------------------------------------+
+| ``REAL`` | float |
++-------------+---------------------------------------------+
+| ``TEXT`` | depends on text_factory, unicode by default |
++-------------+---------------------------------------------+
+| ``BLOB`` | buffer |
++-------------+---------------------------------------------+
+
+The type system of the :mod:`sqlite3` module is extensible in two ways: you can
+store additional Python types in a SQLite database via object adaptation, and
+you can let the :mod:`sqlite3` module convert SQLite types to different Python
+types via converters.
+
+
+Using adapters to store additional Python types in SQLite databases
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+As described before, SQLite supports only a limited set of types natively. To
+use other Python types with SQLite, you must **adapt** them to one of the
+sqlite3 module's supported types for SQLite: one of NoneType, int, long, float,
+str, unicode, buffer.
+
+The :mod:`sqlite3` module uses Python object adaptation, as described in
+:pep:`246` for this. The protocol to use is :class:`PrepareProtocol`.
+
+There are two ways to enable the :mod:`sqlite3` module to adapt a custom Python
+type to one of the supported ones.
+
+
+Letting your object adapt itself
+""""""""""""""""""""""""""""""""
+
+This is a good approach if you write the class yourself. Let's suppose you have
+a class like this::
+
+ class Point(object):
+ def __init__(self, x, y):
+ self.x, self.y = x, y
+
+Now you want to store the point in a single SQLite column. First you'll have to
+choose one of the supported types first to be used for representing the point.
+Let's just use str and separate the coordinates using a semicolon. Then you need
+to give your class a method ``__conform__(self, protocol)`` which must return
+the converted value. The parameter *protocol* will be :class:`PrepareProtocol`.
+
+.. literalinclude:: ../includes/sqlite3/adapter_point_1.py
+
+
+Registering an adapter callable
+"""""""""""""""""""""""""""""""
+
+The other possibility is to create a function that converts the type to the
+string representation and register the function with :meth:`register_adapter`.
+
+.. note::
+
+ The type/class to adapt must be a new-style class, i. e. it must have
+ :class:`object` as one of its bases.
+
+.. literalinclude:: ../includes/sqlite3/adapter_point_2.py
+
+The :mod:`sqlite3` module has two default adapters for Python's built-in
+:class:`datetime.date` and :class:`datetime.datetime` types. Now let's suppose
+we want to store :class:`datetime.datetime` objects not in ISO representation,
+but as a Unix timestamp.
+
+.. literalinclude:: ../includes/sqlite3/adapter_datetime.py
+
+
+Converting SQLite values to custom Python types
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Writing an adapter lets you send custom Python types to SQLite. But to make it
+really useful we need to make the Python to SQLite to Python roundtrip work.
+
+Enter converters.
+
+Let's go back to the :class:`Point` class. We stored the x and y coordinates
+separated via semicolons as strings in SQLite.
+
+First, we'll define a converter function that accepts the string as a parameter
+and constructs a :class:`Point` object from it.
+
+.. note::
+
+ Converter functions **always** get called with a string, no matter under which
+ data type you sent the value to SQLite.
+
+.. note::
+
+ Converter names are looked up in a case-sensitive manner.
+
+::
+
+ def convert_point(s):
+ x, y = map(float, s.split(";"))
+ return Point(x, y)
+
+Now you need to make the :mod:`sqlite3` module know that what you select from
+the database is actually a point. There are two ways of doing this:
+
+* Implicitly via the declared type
+
+* Explicitly via the column name
+
+Both ways are described in section :ref:`sqlite3-module-contents`, in the entries
+for the constants :const:`PARSE_DECLTYPES` and :const:`PARSE_COLNAMES`.
+
+The following example illustrates both approaches.
+
+.. literalinclude:: ../includes/sqlite3/converter_point.py
+
+
+Default adapters and converters
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+There are default adapters for the date and datetime types in the datetime
+module. They will be sent as ISO dates/ISO timestamps to SQLite.
+
+The default converters are registered under the name "date" for
+:class:`datetime.date` and under the name "timestamp" for
+:class:`datetime.datetime`.
+
+This way, you can use date/timestamps from Python without any additional
+fiddling in most cases. The format of the adapters is also compatible with the
+experimental SQLite date/time functions.
+
+The following example demonstrates this.
+
+.. literalinclude:: ../includes/sqlite3/pysqlite_datetime.py
+
+
+.. _sqlite3-controlling-transactions:
+
+Controlling Transactions
+------------------------
+
+By default, the :mod:`sqlite3` module opens transactions implicitly before a
+Data Modification Language (DML) statement (i.e. INSERT/UPDATE/DELETE/REPLACE),
+and commits transactions implicitly before a non-DML, non-query statement (i. e.
+anything other than SELECT/INSERT/UPDATE/DELETE/REPLACE).
+
+So if you are within a transaction and issue a command like ``CREATE TABLE
+...``, ``VACUUM``, ``PRAGMA``, the :mod:`sqlite3` module will commit implicitly
+before executing that command. There are two reasons for doing that. The first
+is that some of these commands don't work within transactions. The other reason
+is that pysqlite needs to keep track of the transaction state (if a transaction
+is active or not).
+
+You can control which kind of "BEGIN" statements pysqlite implicitly executes
+(or none at all) via the *isolation_level* parameter to the :func:`connect`
+call, or via the :attr:`isolation_level` property of connections.
+
+If you want **autocommit mode**, then set :attr:`isolation_level` to None.
+
+Otherwise leave it at its default, which will result in a plain "BEGIN"
+statement, or set it to one of SQLite's supported isolation levels: DEFERRED,
+IMMEDIATE or EXCLUSIVE.
+
+As the :mod:`sqlite3` module needs to keep track of the transaction state, you
+should not use ``OR ROLLBACK`` or ``ON CONFLICT ROLLBACK`` in your SQL. Instead,
+catch the :exc:`IntegrityError` and call the :meth:`rollback` method of the
+connection yourself.
+
+
+Using pysqlite efficiently
+--------------------------
+
+
+Using shortcut methods
+^^^^^^^^^^^^^^^^^^^^^^
+
+Using the nonstandard :meth:`execute`, :meth:`executemany` and
+:meth:`executescript` methods of the :class:`Connection` object, your code can
+be written more concisely because you don't have to create the (often
+superfluous) :class:`Cursor` objects explicitly. Instead, the :class:`Cursor`
+objects are created implicitly and these shortcut methods return the cursor
+objects. This way, you can execute a SELECT statement and iterate over it
+directly using only a single call on the :class:`Connection` object.
+
+.. literalinclude:: ../includes/sqlite3/shortcut_methods.py
+
+
+Accessing columns by name instead of by index
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+One useful feature of the :mod:`sqlite3` module is the builtin
+:class:`sqlite3.Row` class designed to be used as a row factory.
+
+Rows wrapped with this class can be accessed both by index (like tuples) and
+case-insensitively by name:
+
+.. literalinclude:: ../includes/sqlite3/rowclass.py
+
diff --git a/Doc/library/stat.rst b/Doc/library/stat.rst
new file mode 100644
index 0000000000..430bb23fee
--- /dev/null
+++ b/Doc/library/stat.rst
@@ -0,0 +1,167 @@
+
+:mod:`stat` --- Interpreting :func:`stat` results
+=================================================
+
+.. module:: stat
+ :synopsis: Utilities for interpreting the results of os.stat(), os.lstat() and os.fstat().
+.. sectionauthor:: Skip Montanaro <skip@automatrix.com>
+
+
+The :mod:`stat` module defines constants and functions for interpreting the
+results of :func:`os.stat`, :func:`os.fstat` and :func:`os.lstat` (if they
+exist). For complete details about the :cfunc:`stat`, :cfunc:`fstat` and
+:cfunc:`lstat` calls, consult the documentation for your system.
+
+The :mod:`stat` module defines the following functions to test for specific file
+types:
+
+
+.. function:: S_ISDIR(mode)
+
+ Return non-zero if the mode is from a directory.
+
+
+.. function:: S_ISCHR(mode)
+
+ Return non-zero if the mode is from a character special device file.
+
+
+.. function:: S_ISBLK(mode)
+
+ Return non-zero if the mode is from a block special device file.
+
+
+.. function:: S_ISREG(mode)
+
+ Return non-zero if the mode is from a regular file.
+
+
+.. function:: S_ISFIFO(mode)
+
+ Return non-zero if the mode is from a FIFO (named pipe).
+
+
+.. function:: S_ISLNK(mode)
+
+ Return non-zero if the mode is from a symbolic link.
+
+
+.. function:: S_ISSOCK(mode)
+
+ Return non-zero if the mode is from a socket.
+
+Two additional functions are defined for more general manipulation of the file's
+mode:
+
+
+.. function:: S_IMODE(mode)
+
+ Return the portion of the file's mode that can be set by :func:`os.chmod`\
+ ---that is, the file's permission bits, plus the sticky bit, set-group-id, and
+ set-user-id bits (on systems that support them).
+
+
+.. function:: S_IFMT(mode)
+
+ Return the portion of the file's mode that describes the file type (used by the
+ :func:`S_IS\*` functions above).
+
+Normally, you would use the :func:`os.path.is\*` functions for testing the type
+of a file; the functions here are useful when you are doing multiple tests of
+the same file and wish to avoid the overhead of the :cfunc:`stat` system call
+for each test. These are also useful when checking for information about a file
+that isn't handled by :mod:`os.path`, like the tests for block and character
+devices.
+
+All the variables below are simply symbolic indexes into the 10-tuple returned
+by :func:`os.stat`, :func:`os.fstat` or :func:`os.lstat`.
+
+
+.. data:: ST_MODE
+
+ Inode protection mode.
+
+
+.. data:: ST_INO
+
+ Inode number.
+
+
+.. data:: ST_DEV
+
+ Device inode resides on.
+
+
+.. data:: ST_NLINK
+
+ Number of links to the inode.
+
+
+.. data:: ST_UID
+
+ User id of the owner.
+
+
+.. data:: ST_GID
+
+ Group id of the owner.
+
+
+.. data:: ST_SIZE
+
+ Size in bytes of a plain file; amount of data waiting on some special files.
+
+
+.. data:: ST_ATIME
+
+ Time of last access.
+
+
+.. data:: ST_MTIME
+
+ Time of last modification.
+
+
+.. data:: ST_CTIME
+
+ The "ctime" as reported by the operating system. On some systems (like Unix) is
+ the time of the last metadata change, and, on others (like Windows), is the
+ creation time (see platform documentation for details).
+
+The interpretation of "file size" changes according to the file type. For plain
+files this is the size of the file in bytes. For FIFOs and sockets under most
+flavors of Unix (including Linux in particular), the "size" is the number of
+bytes waiting to be read at the time of the call to :func:`os.stat`,
+:func:`os.fstat`, or :func:`os.lstat`; this can sometimes be useful, especially
+for polling one of these special files after a non-blocking open. The meaning
+of the size field for other character and block devices varies more, depending
+on the implementation of the underlying system call.
+
+Example::
+
+ import os, sys
+ from stat import *
+
+ def walktree(top, callback):
+ '''recursively descend the directory tree rooted at top,
+ calling the callback function for each regular file'''
+
+ for f in os.listdir(top):
+ pathname = os.path.join(top, f)
+ mode = os.stat(pathname)[ST_MODE]
+ if S_ISDIR(mode):
+ # It's a directory, recurse into it
+ walktree(pathname, callback)
+ elif S_ISREG(mode):
+ # It's a file, call the callback function
+ callback(pathname)
+ else:
+ # Unknown file type, print a message
+ print 'Skipping %s' % pathname
+
+ def visitfile(file):
+ print 'visiting', file
+
+ if __name__ == '__main__':
+ walktree(sys.argv[1], visitfile)
+
diff --git a/Doc/library/statvfs.rst b/Doc/library/statvfs.rst
new file mode 100644
index 0000000000..6ec7c38806
--- /dev/null
+++ b/Doc/library/statvfs.rst
@@ -0,0 +1,67 @@
+
+:mod:`statvfs` --- Constants used with :func:`os.statvfs`
+=========================================================
+
+.. module:: statvfs
+ :synopsis: Constants for interpreting the result of os.statvfs().
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+.. % LaTeX'ed from comments in module
+
+The :mod:`statvfs` module defines constants so interpreting the result if
+:func:`os.statvfs`, which returns a tuple, can be made without remembering
+"magic numbers." Each of the constants defined in this module is the *index* of
+the entry in the tuple returned by :func:`os.statvfs` that contains the
+specified information.
+
+
+.. data:: F_BSIZE
+
+ Preferred file system block size.
+
+
+.. data:: F_FRSIZE
+
+ Fundamental file system block size.
+
+
+.. data:: F_BLOCKS
+
+ Total number of blocks in the filesystem.
+
+
+.. data:: F_BFREE
+
+ Total number of free blocks.
+
+
+.. data:: F_BAVAIL
+
+ Free blocks available to non-super user.
+
+
+.. data:: F_FILES
+
+ Total number of file nodes.
+
+
+.. data:: F_FFREE
+
+ Total number of free file nodes.
+
+
+.. data:: F_FAVAIL
+
+ Free nodes available to non-super user.
+
+
+.. data:: F_FLAG
+
+ Flags. System dependent: see :cfunc:`statvfs` man page.
+
+
+.. data:: F_NAMEMAX
+
+ Maximum file name length.
+
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
new file mode 100644
index 0000000000..34c943c2ee
--- /dev/null
+++ b/Doc/library/stdtypes.rst
@@ -0,0 +1,2409 @@
+.. XXX: reference/datamodel and this have quite a few overlaps!
+
+
+.. _bltin-types:
+
+**************
+Built-in Types
+**************
+
+The following sections describe the standard types that are built into the
+interpreter.
+
+.. note::
+
+ Historically (until release 2.2), Python's built-in types have differed from
+ user-defined types because it was not possible to use the built-in types as the
+ basis for object-oriented inheritance. This limitation no longer
+ exists.
+
+.. index:: pair: built-in; types
+
+The principal built-in types are numerics, sequences, mappings, files, classes,
+instances and exceptions.
+
+.. index:: statement: print
+
+Some operations are supported by several object types; in particular,
+practically all objects can be compared, tested for truth value, and converted
+to a string (with the :func:`repr` function or the slightly different
+:func:`str` function). The latter function is implicitly used when an object is
+written by the :func:`print` function.
+
+
+.. _truth:
+
+Truth Value Testing
+===================
+
+.. index::
+ statement: if
+ statement: while
+ pair: truth; value
+ pair: Boolean; operations
+ single: false
+
+Any object can be tested for truth value, for use in an :keyword:`if` or
+:keyword:`while` condition or as operand of the Boolean operations below. The
+following values are considered false:
+
+ .. index:: single: None (Built-in object)
+
+* ``None``
+
+ .. index:: single: False (Built-in object)
+
+* ``False``
+
+* zero of any numeric type, for example, ``0``, ``0L``, ``0.0``, ``0j``.
+
+* any empty sequence, for example, ``''``, ``()``, ``[]``.
+
+* any empty mapping, for example, ``{}``.
+
+* instances of user-defined classes, if the class defines a :meth:`__bool__` or
+ :meth:`__len__` method, when that method returns the integer zero or
+ :class:`bool` value ``False``. [#]_
+
+.. index:: single: true
+
+All other values are considered true --- so objects of many types are always
+true.
+
+.. index::
+ operator: or
+ operator: and
+ single: False
+ single: True
+
+Operations and built-in functions that have a Boolean result always return ``0``
+or ``False`` for false and ``1`` or ``True`` for true, unless otherwise stated.
+(Important exception: the Boolean operations ``or`` and ``and`` always return
+one of their operands.)
+
+
+.. _boolean:
+
+Boolean Operations --- :keyword:`and`, :keyword:`or`, :keyword:`not`
+====================================================================
+
+.. index:: pair: Boolean; operations
+
+These are the Boolean operations, ordered by ascending priority:
+
++-------------+---------------------------------+-------+
+| Operation | Result | Notes |
++=============+=================================+=======+
+| ``x or y`` | if *x* is false, then *y*, else | \(1) |
+| | *x* | |
++-------------+---------------------------------+-------+
+| ``x and y`` | if *x* is false, then *x*, else | \(2) |
+| | *y* | |
++-------------+---------------------------------+-------+
+| ``not x`` | if *x* is false, then ``True``, | \(3) |
+| | else ``False`` | |
++-------------+---------------------------------+-------+
+
+.. index::
+ operator: and
+ operator: or
+ operator: not
+
+Notes:
+
+(1)
+ This is a short-circuit operator, so it only evaluates the second
+ argument if the first one is :const:`False`.
+
+(2)
+ This is a short-circuit operator, so it only evaluates the second
+ argument if the first one is :const:`True`.
+
+(3)
+ ``not`` has a lower priority than non-Boolean operators, so ``not a == b`` is
+ interpreted as ``not (a == b)``, and ``a == not b`` is a syntax error.
+
+
+.. _stdcomparisons:
+
+Comparisons
+===========
+
+.. index:: pair: chaining; comparisons
+
+Comparison operations are supported by all objects. They all have the same
+priority (which is higher than that of the Boolean operations). Comparisons can
+be chained arbitrarily; for example, ``x < y <= z`` is equivalent to ``x < y and
+y <= z``, except that *y* is evaluated only once (but in both cases *z* is not
+evaluated at all when ``x < y`` is found to be false).
+
+This table summarizes the comparison operations:
+
++------------+-------------------------+-------+
+| Operation | Meaning | Notes |
++============+=========================+=======+
+| ``<`` | strictly less than | |
++------------+-------------------------+-------+
+| ``<=`` | less than or equal | |
++------------+-------------------------+-------+
+| ``>`` | strictly greater than | |
++------------+-------------------------+-------+
+| ``>=`` | greater than or equal | |
++------------+-------------------------+-------+
+| ``==`` | equal | |
++------------+-------------------------+-------+
+| ``!=`` | not equal | |
++------------+-------------------------+-------+
+| ``is`` | object identity | |
++------------+-------------------------+-------+
+| ``is not`` | negated object identity | |
++------------+-------------------------+-------+
+
+.. index::
+ pair: operator; comparison
+ operator: ==
+ operator: is
+ operator: is not
+
+.. % XXX *All* others have funny characters < ! >
+
+.. index::
+ pair: object; numeric
+ pair: objects; comparing
+
+Objects of different types, except different numeric types and different string
+types, never compare equal; such objects are ordered consistently but
+arbitrarily (so that sorting a heterogeneous array yields a consistent result).
+Furthermore, some types (for example, file objects) support only a degenerate
+notion of comparison where any two objects of that type are unequal. Again,
+such objects are ordered arbitrarily but consistently. The ``<``, ``<=``, ``>``
+and ``>=`` operators will raise a :exc:`TypeError` exception when any operand is
+a complex number.
+
+.. index:: single: __cmp__() (instance method)
+
+Instances of a class normally compare as non-equal unless the class defines the
+:meth:`__cmp__` method. Refer to :ref:`customization`) for information on the
+use of this method to effect object comparisons.
+
+**Implementation note:** Objects of different types except numbers are ordered
+by their type names; objects of the same types that don't support proper
+comparison are ordered by their address.
+
+.. index::
+ operator: in
+ operator: not in
+
+Two more operations with the same syntactic priority, ``in`` and ``not in``, are
+supported only by sequence types (below).
+
+
+.. _typesnumeric:
+
+Numeric Types --- :class:`int`, :class:`float`, :class:`long`, :class:`complex`
+===============================================================================
+
+.. index::
+ object: numeric
+ object: Boolean
+ object: integer
+ object: long integer
+ object: floating point
+ object: complex number
+ pair: C; language
+
+There are four distinct numeric types: :dfn:`plain integers`, :dfn:`long
+integers`, :dfn:`floating point numbers`, and :dfn:`complex numbers`. In
+addition, Booleans are a subtype of plain integers. Plain integers (also just
+called :dfn:`integers`) are implemented using :ctype:`long` in C, which gives
+them at least 32 bits of precision (``sys.maxint`` is always set to the maximum
+plain integer value for the current platform, the minimum value is
+``-sys.maxint - 1``). Long integers have unlimited precision. Floating point
+numbers are implemented using :ctype:`double` in C. All bets on their precision
+are off unless you happen to know the machine you are working with.
+
+Complex numbers have a real and imaginary part, which are each implemented using
+:ctype:`double` in C. To extract these parts from a complex number *z*, use
+``z.real`` and ``z.imag``.
+
+.. index::
+ pair: numeric; literals
+ pair: integer; literals
+ triple: long; integer; literals
+ pair: floating point; literals
+ pair: complex number; literals
+ pair: hexadecimal; literals
+ pair: octal; literals
+
+Numbers are created by numeric literals or as the result of built-in functions
+and operators. Unadorned integer literals (including hex and octal numbers)
+yield plain integers unless the value they denote is too large to be represented
+as a plain integer, in which case they yield a long integer. Integer literals
+with an ``'L'`` or ``'l'`` suffix yield long integers (``'L'`` is preferred
+because ``1l`` looks too much like eleven!). Numeric literals containing a
+decimal point or an exponent sign yield floating point numbers. Appending
+``'j'`` or ``'J'`` to a numeric literal yields a complex number with a zero real
+part. A complex numeric literal is the sum of a real and an imaginary part.
+
+.. index::
+ single: arithmetic
+ builtin: int
+ builtin: long
+ builtin: float
+ builtin: complex
+
+Python fully supports mixed arithmetic: when a binary arithmetic operator has
+operands of different numeric types, the operand with the "narrower" type is
+widened to that of the other, where plain integer is narrower than long integer
+is narrower than floating point is narrower than complex. Comparisons between
+numbers of mixed type use the same rule. [#]_ The constructors :func:`int`,
+:func:`long`, :func:`float`, and :func:`complex` can be used to produce numbers
+of a specific type.
+
+All numeric types (except complex) support the following operations, sorted by
+ascending priority (operations in the same box have the same priority; all
+numeric operations have a higher priority than comparison operations):
+
++--------------------+---------------------------------+--------+
+| Operation | Result | Notes |
++====================+=================================+========+
+| ``x + y`` | sum of *x* and *y* | |
++--------------------+---------------------------------+--------+
+| ``x - y`` | difference of *x* and *y* | |
++--------------------+---------------------------------+--------+
+| ``x * y`` | product of *x* and *y* | |
++--------------------+---------------------------------+--------+
+| ``x / y`` | quotient of *x* and *y* | \(1) |
++--------------------+---------------------------------+--------+
+| ``x // y`` | (floored) quotient of *x* and | \(5) |
+| | *y* | |
++--------------------+---------------------------------+--------+
+| ``x % y`` | remainder of ``x / y`` | \(4) |
++--------------------+---------------------------------+--------+
+| ``-x`` | *x* negated | |
++--------------------+---------------------------------+--------+
+| ``+x`` | *x* unchanged | |
++--------------------+---------------------------------+--------+
+| ``abs(x)`` | absolute value or magnitude of | |
+| | *x* | |
++--------------------+---------------------------------+--------+
+| ``int(x)`` | *x* converted to integer | \(2) |
++--------------------+---------------------------------+--------+
+| ``long(x)`` | *x* converted to long integer | \(2) |
++--------------------+---------------------------------+--------+
+| ``float(x)`` | *x* converted to floating point | |
++--------------------+---------------------------------+--------+
+| ``complex(re,im)`` | a complex number with real part | |
+| | *re*, imaginary part *im*. | |
+| | *im* defaults to zero. | |
++--------------------+---------------------------------+--------+
+| ``c.conjugate()`` | conjugate of the complex number | |
+| | *c* | |
++--------------------+---------------------------------+--------+
+| ``divmod(x, y)`` | the pair ``(x // y, x % y)`` | (3)(4) |
++--------------------+---------------------------------+--------+
+| ``pow(x, y)`` | *x* to the power *y* | |
++--------------------+---------------------------------+--------+
+| ``x ** y`` | *x* to the power *y* | |
++--------------------+---------------------------------+--------+
+
+.. index::
+ triple: operations on; numeric; types
+ single: conjugate() (complex number method)
+
+Notes:
+
+(1)
+ .. index::
+ pair: integer; division
+ triple: long; integer; division
+
+ For (plain or long) integer division, the result is an integer. The result is
+ always rounded towards minus infinity: 1/2 is 0, (-1)/2 is -1, 1/(-2) is -1, and
+ (-1)/(-2) is 0. Note that the result is a long integer if either operand is a
+ long integer, regardless of the numeric value.
+
+(2)
+ .. index::
+ module: math
+ single: floor() (in module math)
+ single: ceil() (in module math)
+ pair: numeric; conversions
+ pair: C; language
+
+ Conversion from floating point to (long or plain) integer may round or truncate
+ as in C; see functions :func:`floor` and :func:`ceil` in the :mod:`math` module
+ for well-defined conversions.
+
+(3)
+ See :ref:`built-in-funcs` for a full description.
+
+(4)
+ Complex floor division operator, modulo operator, and :func:`divmod`.
+
+ .. deprecated:: 2.3
+ Instead convert to float using :func:`abs` if appropriate.
+
+(5)
+ Also referred to as integer division. The resultant value is a whole integer,
+ though the result's type is not necessarily int.
+
+.. % XXXJH exceptions: overflow (when? what operations?) zerodivision
+
+
+.. _bitstring-ops:
+
+Bit-string Operations on Integer Types
+--------------------------------------
+
+.. _bit-string-operations:
+
+Plain and long integer types support additional operations that make sense only
+for bit-strings. Negative numbers are treated as their 2's complement value
+(for long integers, this assumes a sufficiently large number of bits that no
+overflow occurs during the operation).
+
+The priorities of the binary bit-wise operations are all lower than the numeric
+operations and higher than the comparisons; the unary operation ``~`` has the
+same priority as the other unary numeric operations (``+`` and ``-``).
+
+This table lists the bit-string operations sorted in ascending priority
+(operations in the same box have the same priority):
+
++------------+--------------------------------+----------+
+| Operation | Result | Notes |
++============+================================+==========+
+| ``x | y`` | bitwise :dfn:`or` of *x* and | |
+| | *y* | |
++------------+--------------------------------+----------+
+| ``x ^ y`` | bitwise :dfn:`exclusive or` of | |
+| | *x* and *y* | |
++------------+--------------------------------+----------+
+| ``x & y`` | bitwise :dfn:`and` of *x* and | |
+| | *y* | |
++------------+--------------------------------+----------+
+| ``x << n`` | *x* shifted left by *n* bits | (1), (2) |
++------------+--------------------------------+----------+
+| ``x >> n`` | *x* shifted right by *n* bits | (1), (3) |
++------------+--------------------------------+----------+
+| ``~x`` | the bits of *x* inverted | |
++------------+--------------------------------+----------+
+
+.. index::
+ triple: operations on; integer; types
+ pair: bit-string; operations
+ pair: shifting; operations
+ pair: masking; operations
+
+Notes:
+
+(1)
+ Negative shift counts are illegal and cause a :exc:`ValueError` to be raised.
+
+(2)
+ A left shift by *n* bits is equivalent to multiplication by ``pow(2, n)``
+ without overflow check.
+
+(3)
+ A right shift by *n* bits is equivalent to division by ``pow(2, n)`` without
+ overflow check.
+
+
+.. _typeiter:
+
+Iterator Types
+==============
+
+.. versionadded:: 2.2
+
+.. index::
+ single: iterator protocol
+ single: protocol; iterator
+ single: sequence; iteration
+ single: container; iteration over
+
+Python supports a concept of iteration over containers. This is implemented
+using two distinct methods; these are used to allow user-defined classes to
+support iteration. Sequences, described below in more detail, always support
+the iteration methods.
+
+One method needs to be defined for container objects to provide iteration
+support:
+
+
+.. method:: container.__iter__()
+
+ Return an iterator object. The object is required to support the iterator
+ protocol described below. If a container supports different types of
+ iteration, additional methods can be provided to specifically request
+ iterators for those iteration types. (An example of an object supporting
+ multiple forms of iteration would be a tree structure which supports both
+ breadth-first and depth-first traversal.) This method corresponds to the
+ :attr:`tp_iter` slot of the type structure for Python objects in the Python/C
+ API.
+
+The iterator objects themselves are required to support the following two
+methods, which together form the :dfn:`iterator protocol`:
+
+
+.. method:: iterator.__iter__()
+
+ Return the iterator object itself. This is required to allow both containers
+ and iterators to be used with the :keyword:`for` and :keyword:`in` statements.
+ This method corresponds to the :attr:`tp_iter` slot of the type structure for
+ Python objects in the Python/C API.
+
+
+.. method:: iterator.next()
+
+ Return the next item from the container. If there are no further items, raise
+ the :exc:`StopIteration` exception. This method corresponds to the
+ :attr:`tp_iternext` slot of the type structure for Python objects in the
+ Python/C API.
+
+Python defines several iterator objects to support iteration over general and
+specific sequence types, dictionaries, and other more specialized forms. The
+specific types are not important beyond their implementation of the iterator
+protocol.
+
+The intention of the protocol is that once an iterator's :meth:`__next__` method
+raises :exc:`StopIteration`, it will continue to do so on subsequent calls.
+Implementations that do not obey this property are deemed broken. (This
+constraint was added in Python 2.3; in Python 2.2, various iterators are broken
+according to this rule.)
+
+Python's generators provide a convenient way to implement the iterator protocol.
+If a container object's :meth:`__iter__` method is implemented as a generator,
+it will automatically return an iterator object (technically, a generator
+object) supplying the :meth:`__iter__` and :meth:`__next__` methods.
+
+
+.. _typesseq:
+
+Sequence Types --- :class:`str`, :class:`unicode`, :class:`list`, :class:`tuple`, :class:`buffer`, :class:`range`
+=================================================================================================================
+
+There are six sequence types: strings, Unicode strings, lists, tuples, buffers,
+and range objects.
+(For other containers see the built in :class:`dict`, :class:`list`,
+:class:`set`, and :class:`tuple` classes, and the :mod:`collections`
+module.)
+
+
+.. index::
+ object: sequence
+ object: string
+ object: tuple
+ object: list
+ object: buffer
+ object: range
+
+String literals are written in single or double quotes: ``'xyzzy'``,
+``"frobozz"``. See :ref:`strings` for more about string literals. In addition
+to the functionality described here, there are also string-specific methods
+described in the :ref:`string-methods` section. Lists are constructed with
+square brackets, separating items with commas: ``[a, b, c]``. Tuples are
+constructed by the comma operator (not within square brackets), with or without
+enclosing parentheses, but an empty tuple must have the enclosing parentheses,
+such as ``a, b, c`` or ``()``. A single item tuple must have a trailing comma,
+such as ``(d,)``.
+
+Buffer objects are not directly supported by Python syntax, but can be created
+by calling the builtin function :func:`buffer`. They don't support
+concatenation or repetition.
+
+Objects of type range are similar to buffers in that there is no specific syntax to
+create them, but they are created using the :func:`range` function. They don't
+support slicing, concatenation or repetition, and using ``in``, ``not in``,
+:func:`min` or :func:`max` on them is inefficient.
+
+Most sequence types support the following operations. The ``in`` and ``not in``
+operations have the same priorities as the comparison operations. The ``+`` and
+``*`` operations have the same priority as the corresponding numeric operations.
+[#]_
+
+This table lists the sequence operations sorted in ascending priority
+(operations in the same box have the same priority). In the table, *s* and *t*
+are sequences of the same type; *n*, *i* and *j* are integers:
+
++------------------+--------------------------------+----------+
+| Operation | Result | Notes |
++==================+================================+==========+
+| ``x in s`` | ``True`` if an item of *s* is | \(1) |
+| | equal to *x*, else ``False`` | |
++------------------+--------------------------------+----------+
+| ``x not in s`` | ``False`` if an item of *s* is | \(1) |
+| | equal to *x*, else ``True`` | |
++------------------+--------------------------------+----------+
+| ``s + t`` | the concatenation of *s* and | \(6) |
+| | *t* | |
++------------------+--------------------------------+----------+
+| ``s * n, n * s`` | *n* shallow copies of *s* | \(2) |
+| | concatenated | |
++------------------+--------------------------------+----------+
+| ``s[i]`` | *i*'th item of *s*, origin 0 | \(3) |
++------------------+--------------------------------+----------+
+| ``s[i:j]`` | slice of *s* from *i* to *j* | (3), (4) |
++------------------+--------------------------------+----------+
+| ``s[i:j:k]`` | slice of *s* from *i* to *j* | (3), (5) |
+| | with step *k* | |
++------------------+--------------------------------+----------+
+| ``len(s)`` | length of *s* | |
++------------------+--------------------------------+----------+
+| ``min(s)`` | smallest item of *s* | |
++------------------+--------------------------------+----------+
+| ``max(s)`` | largest item of *s* | |
++------------------+--------------------------------+----------+
+
+Sequence types also support comparisons. In particular, tuples and lists
+are compared lexicographically by comparing corresponding
+elements. This means that to compare equal, every element must compare
+equal and the two sequences must be of the same type and have the same
+length. (For full details see :ref:`comparisons` in the language
+reference.)
+
+.. index::
+ triple: operations on; sequence; types
+ builtin: len
+ builtin: min
+ builtin: max
+ pair: concatenation; operation
+ pair: repetition; operation
+ pair: subscript; operation
+ pair: slice; operation
+ pair: extended slice; operation
+ operator: in
+ operator: not in
+
+Notes:
+
+(1)
+ When *s* is a string or Unicode string object the ``in`` and ``not in``
+ operations act like a substring test. In Python versions before 2.3, *x* had to
+ be a string of length 1. In Python 2.3 and beyond, *x* may be a string of any
+ length.
+
+(2)
+ Values of *n* less than ``0`` are treated as ``0`` (which yields an empty
+ sequence of the same type as *s*). Note also that the copies are shallow;
+ nested structures are not copied. This often haunts new Python programmers;
+ consider::
+
+ >>> lists = [[]] * 3
+ >>> lists
+ [[], [], []]
+ >>> lists[0].append(3)
+ >>> lists
+ [[3], [3], [3]]
+
+ What has happened is that ``[[]]`` is a one-element list containing an empty
+ list, so all three elements of ``[[]] * 3`` are (pointers to) this single empty
+ list. Modifying any of the elements of ``lists`` modifies this single list.
+ You can create a list of different lists this way::
+
+ >>> lists = [[] for i in range(3)]
+ >>> lists[0].append(3)
+ >>> lists[1].append(5)
+ >>> lists[2].append(7)
+ >>> lists
+ [[3], [5], [7]]
+
+(3)
+ If *i* or *j* is negative, the index is relative to the end of the string:
+ ``len(s) + i`` or ``len(s) + j`` is substituted. But note that ``-0`` is still
+ ``0``.
+
+(4)
+ The slice of *s* from *i* to *j* is defined as the sequence of items with index
+ *k* such that ``i <= k < j``. If *i* or *j* is greater than ``len(s)``, use
+ ``len(s)``. If *i* is omitted or ``None``, use ``0``. If *j* is omitted or
+ ``None``, use ``len(s)``. If *i* is greater than or equal to *j*, the slice is
+ empty.
+
+(5)
+ The slice of *s* from *i* to *j* with step *k* is defined as the sequence of
+ items with index ``x = i + n*k`` such that 0 ≤n < (j-i)/(k). In other words,
+ the indices are ``i``, ``i+k``, ``i+2*k``, ``i+3*k`` and so on, stopping when
+ *j* is reached (but never including *j*). If *i* or *j* is greater than
+ ``len(s)``, use ``len(s)``. If *i* or *j* are omitted or ``None``, they become
+ "end" values (which end depends on the sign of *k*). Note, *k* cannot be zero.
+ If *k* is ``None``, it is treated like ``1``.
+
+(6)
+ If *s* and *t* are both strings, some Python implementations such as CPython can
+ usually perform an in-place optimization for assignments of the form ``s=s+t``
+ or ``s+=t``. When applicable, this optimization makes quadratic run-time much
+ less likely. This optimization is both version and implementation dependent.
+ For performance sensitive code, it is preferable to use the :meth:`str.join`
+ method which assures consistent linear concatenation performance across versions
+ and implementations.
+
+ .. versionchanged:: 2.4
+ Formerly, string concatenation never occurred in-place.
+
+
+.. _string-methods:
+
+String Methods
+--------------
+
+.. index:: pair: string; methods
+
+Below are listed the string methods which both 8-bit strings and Unicode objects
+support. In addition, Python's strings support the sequence type methods
+described in the :ref:`typesseq` section. To output formatted strings
+use template strings or the ``%`` operator described in the
+:ref:`string-formatting` section. Also, see the :mod:`re` module for
+string functions based on regular expressions.
+
+.. method:: str.capitalize()
+
+ Return a copy of the string with only its first character capitalized.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.center(width[, fillchar])
+
+ Return centered in a string of length *width*. Padding is done using the
+ specified *fillchar* (default is a space).
+
+ .. versionchanged:: 2.4
+ Support for the *fillchar* argument.
+
+
+.. method:: str.count(sub[, start[, end]])
+
+ Return the number of occurrences of substring *sub* in string S\
+ ``[start:end]``. Optional arguments *start* and *end* are interpreted as in
+ slice notation.
+
+
+.. method:: str.decode([encoding[, errors]])
+
+ Decodes the string using the codec registered for *encoding*. *encoding*
+ defaults to the default string encoding. *errors* may be given to set a
+ different error handling scheme. The default is ``'strict'``, meaning that
+ encoding errors raise :exc:`UnicodeError`. Other possible values are
+ ``'ignore'``, ``'replace'`` and any other name registered via
+ :func:`codecs.register_error`, see section :ref:`codec-base-classes`.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.3
+ Support for other error handling schemes added.
+
+
+.. method:: str.encode([encoding[,errors]])
+
+ Return an encoded version of the string. Default encoding is the current
+ default string encoding. *errors* may be given to set a different error
+ handling scheme. The default for *errors* is ``'strict'``, meaning that
+ encoding errors raise a :exc:`UnicodeError`. Other possible values are
+ ``'ignore'``, ``'replace'``, ``'xmlcharrefreplace'``, ``'backslashreplace'`` and
+ any other name registered via :func:`codecs.register_error`, see section
+ :ref:`codec-base-classes`. For a list of possible encodings, see section
+ :ref:`standard-encodings`.
+
+ .. versionadded:: 2.0
+
+ .. versionchanged:: 2.3
+ Support for ``'xmlcharrefreplace'`` and ``'backslashreplace'`` and other error
+ handling schemes added.
+
+
+.. method:: str.endswith(suffix[, start[, end]])
+
+ Return ``True`` if the string ends with the specified *suffix*, otherwise return
+ ``False``. *suffix* can also be a tuple of suffixes to look for. With optional
+ *start*, test beginning at that position. With optional *end*, stop comparing
+ at that position.
+
+ .. versionchanged:: 2.5
+ Accept tuples as *suffix*.
+
+
+.. method:: str.expandtabs([tabsize])
+
+ Return a copy of the string where all tab characters are expanded using spaces.
+ If *tabsize* is not given, a tab size of ``8`` characters is assumed.
+
+
+.. method:: str.find(sub[, start[, end]])
+
+ Return the lowest index in the string where substring *sub* is found, such that
+ *sub* is contained in the range [*start*, *end*]. Optional arguments *start*
+ and *end* are interpreted as in slice notation. Return ``-1`` if *sub* is not
+ found.
+
+
+.. method:: str.index(sub[, start[, end]])
+
+ Like :meth:`find`, but raise :exc:`ValueError` when the substring is not found.
+
+
+.. method:: str.isalnum()
+
+ Return true if all characters in the string are alphanumeric and there is at
+ least one character, false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.isalpha()
+
+ Return true if all characters in the string are alphabetic and there is at least
+ one character, false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.isdigit()
+
+ Return true if all characters in the string are digits and there is at least one
+ character, false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.isidentifier()
+
+ Return true if the string is a valid identifier according to the language
+ definition.
+
+ .. XXX link to the definition?
+
+
+.. method:: str.islower()
+
+ Return true if all cased characters in the string are lowercase and there is at
+ least one cased character, false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.isspace()
+
+ Return true if there are only whitespace characters in the string and there is
+ at least one character, false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.istitle()
+
+ Return true if the string is a titlecased string and there is at least one
+ character, for example uppercase characters may only follow uncased characters
+ and lowercase characters only cased ones. Return false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.isupper()
+
+ Return true if all cased characters in the string are uppercase and there is at
+ least one cased character, false otherwise.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.join(seq)
+
+ Return a string which is the concatenation of the strings in the sequence *seq*.
+ The separator between elements is the string providing this method.
+
+
+.. method:: str.ljust(width[, fillchar])
+
+ Return the string left justified in a string of length *width*. Padding is done
+ using the specified *fillchar* (default is a space). The original string is
+ returned if *width* is less than ``len(s)``.
+
+ .. versionchanged:: 2.4
+ Support for the *fillchar* argument.
+
+
+.. method:: str.lower()
+
+ Return a copy of the string converted to lowercase.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.lstrip([chars])
+
+ Return a copy of the string with leading characters removed. The *chars*
+ argument is a string specifying the set of characters to be removed. If omitted
+ or ``None``, the *chars* argument defaults to removing whitespace. The *chars*
+ argument is not a prefix; rather, all combinations of its values are stripped::
+
+ >>> ' spacious '.lstrip()
+ 'spacious '
+ >>> 'www.example.com'.lstrip('cmowz.')
+ 'example.com'
+
+ .. versionchanged:: 2.2.2
+ Support for the *chars* argument.
+
+
+.. method:: str.partition(sep)
+
+ Split the string at the first occurrence of *sep*, and return a 3-tuple
+ containing the part before the separator, the separator itself, and the part
+ after the separator. If the separator is not found, return a 3-tuple containing
+ the string itself, followed by two empty strings.
+
+ .. versionadded:: 2.5
+
+
+.. method:: str.replace(old, new[, count])
+
+ Return a copy of the string with all occurrences of substring *old* replaced by
+ *new*. If the optional argument *count* is given, only the first *count*
+ occurrences are replaced.
+
+
+.. method:: str.rfind(sub [,start [,end]])
+
+ Return the highest index in the string where substring *sub* is found, such that
+ *sub* is contained within s[start,end]. Optional arguments *start* and *end*
+ are interpreted as in slice notation. Return ``-1`` on failure.
+
+
+.. method:: str.rindex(sub[, start[, end]])
+
+ Like :meth:`rfind` but raises :exc:`ValueError` when the substring *sub* is not
+ found.
+
+
+.. method:: str.rjust(width[, fillchar])
+
+ Return the string right justified in a string of length *width*. Padding is done
+ using the specified *fillchar* (default is a space). The original string is
+ returned if *width* is less than ``len(s)``.
+
+ .. versionchanged:: 2.4
+ Support for the *fillchar* argument.
+
+
+.. method:: str.rpartition(sep)
+
+ Split the string at the last occurrence of *sep*, and return a 3-tuple
+ containing the part before the separator, the separator itself, and the part
+ after the separator. If the separator is not found, return a 3-tuple containing
+ two empty strings, followed by the string itself.
+
+ .. versionadded:: 2.5
+
+
+.. method:: str.rsplit([sep [,maxsplit]])
+
+ Return a list of the words in the string, using *sep* as the delimiter string.
+ If *maxsplit* is given, at most *maxsplit* splits are done, the *rightmost*
+ ones. If *sep* is not specified or ``None``, any whitespace string is a
+ separator. Except for splitting from the right, :meth:`rsplit` behaves like
+ :meth:`split` which is described in detail below.
+
+ .. versionadded:: 2.4
+
+
+.. method:: str.rstrip([chars])
+
+ Return a copy of the string with trailing characters removed. The *chars*
+ argument is a string specifying the set of characters to be removed. If omitted
+ or ``None``, the *chars* argument defaults to removing whitespace. The *chars*
+ argument is not a suffix; rather, all combinations of its values are stripped::
+
+ >>> ' spacious '.rstrip()
+ ' spacious'
+ >>> 'mississippi'.rstrip('ipz')
+ 'mississ'
+
+ .. versionchanged:: 2.2.2
+ Support for the *chars* argument.
+
+
+.. method:: str.split([sep [,maxsplit]])
+
+ Return a list of the words in the string, using *sep* as the delimiter string.
+ If *maxsplit* is given, at most *maxsplit* splits are done. (thus, the list will
+ have at most ``maxsplit+1`` elements). If *maxsplit* is not specified, then
+ there is no limit on the number of splits (all possible splits are made).
+ Consecutive delimiters are not grouped together and are deemed to delimit empty
+ strings (for example, ``'1,,2'.split(',')`` returns ``['1', '', '2']``). The
+ *sep* argument may consist of multiple characters (for example, ``'1, 2,
+ 3'.split(', ')`` returns ``['1', '2', '3']``). Splitting an empty string with a
+ specified separator returns ``['']``.
+
+ If *sep* is not specified or is ``None``, a different splitting algorithm is
+ applied. First, whitespace characters (spaces, tabs, newlines, returns, and
+ formfeeds) are stripped from both ends. Then, words are separated by arbitrary
+ length strings of whitespace characters. Consecutive whitespace delimiters are
+ treated as a single delimiter (``'1 2 3'.split()`` returns ``['1', '2',
+ '3']``). Splitting an empty string or a string consisting of just whitespace
+ returns an empty list.
+
+
+.. method:: str.splitlines([keepends])
+
+ Return a list of the lines in the string, breaking at line boundaries. Line
+ breaks are not included in the resulting list unless *keepends* is given and
+ true.
+
+
+.. method:: str.startswith(prefix[, start[, end]])
+
+ Return ``True`` if string starts with the *prefix*, otherwise return ``False``.
+ *prefix* can also be a tuple of prefixes to look for. With optional *start*,
+ test string beginning at that position. With optional *end*, stop comparing
+ string at that position.
+
+ .. versionchanged:: 2.5
+ Accept tuples as *prefix*.
+
+
+.. method:: str.strip([chars])
+
+ Return a copy of the string with the leading and trailing characters removed.
+ The *chars* argument is a string specifying the set of characters to be removed.
+ If omitted or ``None``, the *chars* argument defaults to removing whitespace.
+ The *chars* argument is not a prefix or suffix; rather, all combinations of its
+ values are stripped::
+
+ >>> ' spacious '.strip()
+ 'spacious'
+ >>> 'www.example.com'.strip('cmowz.')
+ 'example'
+
+ .. versionchanged:: 2.2.2
+ Support for the *chars* argument.
+
+
+.. method:: str.swapcase()
+
+ Return a copy of the string with uppercase characters converted to lowercase and
+ vice versa.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.title()
+
+ Return a titlecased version of the string: words start with uppercase
+ characters, all remaining cased characters are lowercase.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.translate(table[, deletechars])
+
+ Return a copy of the string where all characters occurring in the optional
+ argument *deletechars* are removed, and the remaining characters have been
+ mapped through the given translation table, which must be a string of length
+ 256.
+
+ You can use the :func:`maketrans` helper function in the :mod:`string` module to
+ create a translation table. For string objects, set the *table* argument to
+ ``None`` for translations that only delete characters::
+
+ >>> 'read this short text'.translate(None, 'aeiou')
+ 'rd ths shrt txt'
+
+ .. versionadded:: 2.6
+ Support for a ``None`` *table* argument.
+
+ For Unicode objects, the :meth:`translate` method does not accept the optional
+ *deletechars* argument. Instead, it returns a copy of the *s* where all
+ characters have been mapped through the given translation table which must be a
+ mapping of Unicode ordinals to Unicode ordinals, Unicode strings or ``None``.
+ Unmapped characters are left untouched. Characters mapped to ``None`` are
+ deleted. Note, a more flexible approach is to create a custom character mapping
+ codec using the :mod:`codecs` module (see :mod:`encodings.cp1251` for an
+ example).
+
+
+.. method:: str.upper()
+
+ Return a copy of the string converted to uppercase.
+
+ For 8-bit strings, this method is locale-dependent.
+
+
+.. method:: str.zfill(width)
+
+ Return the numeric string left filled with zeros in a string of length *width*.
+ The original string is returned if *width* is less than ``len(s)``.
+
+ .. versionadded:: 2.2.2
+
+
+.. _string-formatting:
+
+String Formatting Operations
+----------------------------
+
+.. index::
+ single: formatting, string (%)
+ single: interpolation, string (%)
+ single: string; formatting
+ single: string; interpolation
+ single: printf-style formatting
+ single: sprintf-style formatting
+ single: % formatting
+ single: % interpolation
+
+String and Unicode objects have one unique built-in operation: the ``%``
+operator (modulo). This is also known as the string *formatting* or
+*interpolation* operator. Given ``format % values`` (where *format* is a string
+or Unicode object), ``%`` conversion specifications in *format* are replaced
+with zero or more elements of *values*. The effect is similar to the using
+:cfunc:`sprintf` in the C language. If *format* is a Unicode object, or if any
+of the objects being converted using the ``%s`` conversion are Unicode objects,
+the result will also be a Unicode object.
+
+If *format* requires a single argument, *values* may be a single non-tuple
+object. [#]_ Otherwise, *values* must be a tuple with exactly the number of
+items specified by the format string, or a single mapping object (for example, a
+dictionary).
+
+A conversion specifier contains two or more characters and has the following
+components, which must occur in this order:
+
+#. The ``'%'`` character, which marks the start of the specifier.
+
+#. Mapping key (optional), consisting of a parenthesised sequence of characters
+ (for example, ``(somename)``).
+
+#. Conversion flags (optional), which affect the result of some conversion
+ types.
+
+#. Minimum field width (optional). If specified as an ``'*'`` (asterisk), the
+ actual width is read from the next element of the tuple in *values*, and the
+ object to convert comes after the minimum field width and optional precision.
+
+#. Precision (optional), given as a ``'.'`` (dot) followed by the precision. If
+ specified as ``'*'`` (an asterisk), the actual width is read from the next
+ element of the tuple in *values*, and the value to convert comes after the
+ precision.
+
+#. Length modifier (optional).
+
+#. Conversion type.
+
+When the right argument is a dictionary (or other mapping type), then the
+formats in the string *must* include a parenthesised mapping key into that
+dictionary inserted immediately after the ``'%'`` character. The mapping key
+selects the value to be formatted from the mapping. For example::
+
+ >>> print '%(language)s has %(#)03d quote types.' % \
+ {'language': "Python", "#": 2}
+ Python has 002 quote types.
+
+In this case no ``*`` specifiers may occur in a format (since they require a
+sequential parameter list).
+
+The conversion flag characters are:
+
++---------+---------------------------------------------------------------------+
+| Flag | Meaning |
++=========+=====================================================================+
+| ``'#'`` | The value conversion will use the "alternate form" (where defined |
+| | below). |
++---------+---------------------------------------------------------------------+
+| ``'0'`` | The conversion will be zero padded for numeric values. |
++---------+---------------------------------------------------------------------+
+| ``'-'`` | The converted value is left adjusted (overrides the ``'0'`` |
+| | conversion if both are given). |
++---------+---------------------------------------------------------------------+
+| ``' '`` | (a space) A blank should be left before a positive number (or empty |
+| | string) produced by a signed conversion. |
++---------+---------------------------------------------------------------------+
+| ``'+'`` | A sign character (``'+'`` or ``'-'``) will precede the conversion |
+| | (overrides a "space" flag). |
++---------+---------------------------------------------------------------------+
+
+A length modifier (``h``, ``l``, or ``L``) may be present, but is ignored as it
+is not necessary for Python.
+
+The conversion types are:
+
++------------+-----------------------------------------------------+-------+
+| Conversion | Meaning | Notes |
++============+=====================================================+=======+
+| ``'d'`` | Signed integer decimal. | |
++------------+-----------------------------------------------------+-------+
+| ``'i'`` | Signed integer decimal. | |
++------------+-----------------------------------------------------+-------+
+| ``'o'`` | Unsigned octal. | \(1) |
++------------+-----------------------------------------------------+-------+
+| ``'u'`` | Unsigned decimal. | |
++------------+-----------------------------------------------------+-------+
+| ``'x'`` | Unsigned hexadecimal (lowercase). | \(2) |
++------------+-----------------------------------------------------+-------+
+| ``'X'`` | Unsigned hexadecimal (uppercase). | \(2) |
++------------+-----------------------------------------------------+-------+
+| ``'e'`` | Floating point exponential format (lowercase). | \(3) |
++------------+-----------------------------------------------------+-------+
+| ``'E'`` | Floating point exponential format (uppercase). | \(3) |
++------------+-----------------------------------------------------+-------+
+| ``'f'`` | Floating point decimal format. | \(3) |
++------------+-----------------------------------------------------+-------+
+| ``'F'`` | Floating point decimal format. | \(3) |
++------------+-----------------------------------------------------+-------+
+| ``'g'`` | Floating point format. Uses exponential format if | \(4) |
+| | exponent is greater than -4 or less than precision, | |
+| | decimal format otherwise. | |
++------------+-----------------------------------------------------+-------+
+| ``'G'`` | Floating point format. Uses exponential format if | \(4) |
+| | exponent is greater than -4 or less than precision, | |
+| | decimal format otherwise. | |
++------------+-----------------------------------------------------+-------+
+| ``'c'`` | Single character (accepts integer or single | |
+| | character string). | |
++------------+-----------------------------------------------------+-------+
+| ``'r'`` | String (converts any python object using | \(5) |
+| | :func:`repr`). | |
++------------+-----------------------------------------------------+-------+
+| ``'s'`` | String (converts any python object using | \(6) |
+| | :func:`str`). | |
++------------+-----------------------------------------------------+-------+
+| ``'%'`` | No argument is converted, results in a ``'%'`` | |
+| | character in the result. | |
++------------+-----------------------------------------------------+-------+
+
+Notes:
+
+(1)
+ The alternate form causes a leading zero (``'0'``) to be inserted between
+ left-hand padding and the formatting of the number if the leading character
+ of the result is not already a zero.
+
+(2)
+ The alternate form causes a leading ``'0x'`` or ``'0X'`` (depending on whether
+ the ``'x'`` or ``'X'`` format was used) to be inserted between left-hand padding
+ and the formatting of the number if the leading character of the result is not
+ already a zero.
+
+(3)
+ The alternate form causes the result to always contain a decimal point, even if
+ no digits follow it.
+
+ The precision determines the number of digits after the decimal point and
+ defaults to 6.
+
+(4)
+ The alternate form causes the result to always contain a decimal point, and
+ trailing zeroes are not removed as they would otherwise be.
+
+ The precision determines the number of significant digits before and after the
+ decimal point and defaults to 6.
+
+(5)
+ The ``%r`` conversion was added in Python 2.0.
+
+ The precision determines the maximal number of characters used.
+
+(6)
+ If the object or format provided is a :class:`unicode` string, the resulting
+ string will also be :class:`unicode`.
+
+ The precision determines the maximal number of characters used.
+
+Since Python strings have an explicit length, ``%s`` conversions do not assume
+that ``'\0'`` is the end of the string.
+
+.. % XXX Examples?
+
+For safety reasons, floating point precisions are clipped to 50; ``%f``
+conversions for numbers whose absolute value is over 1e25 are replaced by ``%g``
+conversions. [#]_ All other errors raise exceptions.
+
+.. index::
+ module: string
+ module: re
+
+Additional string operations are defined in standard modules :mod:`string` and
+:mod:`re`.
+
+
+.. _typesseq-range:
+
+XRange Type
+-----------
+
+.. index:: object: range
+
+The :class:`range` type is an immutable sequence which is commonly used for
+looping. The advantage of the :class:`range` type is that an :class:`range`
+object will always take the same amount of memory, no matter the size of the
+range it represents. There are no consistent performance advantages.
+
+XRange objects have very little behavior: they only support indexing, iteration,
+and the :func:`len` function.
+
+
+.. _typesseq-mutable:
+
+Mutable Sequence Types
+----------------------
+
+.. index::
+ triple: mutable; sequence; types
+ object: list
+
+List objects support additional operations that allow in-place modification of
+the object. Other mutable sequence types (when added to the language) should
+also support these operations. Strings and tuples are immutable sequence types:
+such objects cannot be modified once created. The following operations are
+defined on mutable sequence types (where *x* is an arbitrary object):
+
++------------------------------+--------------------------------+---------------------+
+| Operation | Result | Notes |
++==============================+================================+=====================+
+| ``s[i] = x`` | item *i* of *s* is replaced by | |
+| | *x* | |
++------------------------------+--------------------------------+---------------------+
+| ``s[i:j] = t`` | slice of *s* from *i* to *j* | |
+| | is replaced by the contents of | |
+| | the iterable *t* | |
++------------------------------+--------------------------------+---------------------+
+| ``del s[i:j]`` | same as ``s[i:j] = []`` | |
++------------------------------+--------------------------------+---------------------+
+| ``s[i:j:k] = t`` | the elements of ``s[i:j:k]`` | \(1) |
+| | are replaced by those of *t* | |
++------------------------------+--------------------------------+---------------------+
+| ``del s[i:j:k]`` | removes the elements of | |
+| | ``s[i:j:k]`` from the list | |
++------------------------------+--------------------------------+---------------------+
+| ``s.append(x)`` | same as ``s[len(s):len(s)] = | \(2) |
+| | [x]`` | |
++------------------------------+--------------------------------+---------------------+
+| ``s.extend(x)`` | same as ``s[len(s):len(s)] = | \(3) |
+| | x`` | |
++------------------------------+--------------------------------+---------------------+
+| ``s.count(x)`` | return number of *i*'s for | |
+| | which ``s[i] == x`` | |
++------------------------------+--------------------------------+---------------------+
+| ``s.index(x[, i[, j]])`` | return smallest *k* such that | \(4) |
+| | ``s[k] == x`` and ``i <= k < | |
+| | j`` | |
++------------------------------+--------------------------------+---------------------+
+| ``s.insert(i, x)`` | same as ``s[i:i] = [x]`` | \(5) |
++------------------------------+--------------------------------+---------------------+
+| ``s.pop([i])`` | same as ``x = s[i]; del s[i]; | \(6) |
+| | return x`` | |
++------------------------------+--------------------------------+---------------------+
+| ``s.remove(x)`` | same as ``del s[s.index(x)]`` | \(4) |
++------------------------------+--------------------------------+---------------------+
+| ``s.reverse()`` | reverses the items of *s* in | \(7) |
+| | place | |
++------------------------------+--------------------------------+---------------------+
+| ``s.sort([cmp[, key[, | sort the items of *s* in place | (7), (8), (9), (10) |
+| reverse]]])`` | | |
++------------------------------+--------------------------------+---------------------+
+
+.. index::
+ triple: operations on; sequence; types
+ triple: operations on; list; type
+ pair: subscript; assignment
+ pair: slice; assignment
+ pair: extended slice; assignment
+ statement: del
+ single: append() (list method)
+ single: extend() (list method)
+ single: count() (list method)
+ single: index() (list method)
+ single: insert() (list method)
+ single: pop() (list method)
+ single: remove() (list method)
+ single: reverse() (list method)
+ single: sort() (list method)
+
+Notes:
+
+(1)
+ *t* must have the same length as the slice it is replacing.
+
+(2)
+ The C implementation of Python has historically accepted multiple parameters and
+ implicitly joined them into a tuple; this no longer works in Python 2.0. Use of
+ this misfeature has been deprecated since Python 1.4.
+
+(3)
+ *x* can be any iterable object.
+
+(4)
+ Raises :exc:`ValueError` when *x* is not found in *s*. When a negative index is
+ passed as the second or third parameter to the :meth:`index` method, the list
+ length is added, as for slice indices. If it is still negative, it is truncated
+ to zero, as for slice indices.
+
+ .. versionchanged:: 2.3
+ Previously, :meth:`index` didn't have arguments for specifying start and stop
+ positions.
+
+(5)
+ When a negative index is passed as the first parameter to the :meth:`insert`
+ method, the list length is added, as for slice indices. If it is still
+ negative, it is truncated to zero, as for slice indices.
+
+ .. versionchanged:: 2.3
+ Previously, all negative indices were truncated to zero.
+
+(6)
+ The :meth:`pop` method is only supported by the list and array types. The
+ optional argument *i* defaults to ``-1``, so that by default the last item is
+ removed and returned.
+
+(7)
+ The :meth:`sort` and :meth:`reverse` methods modify the list in place for
+ economy of space when sorting or reversing a large list. To remind you that
+ they operate by side effect, they don't return the sorted or reversed list.
+
+(8)
+ The :meth:`sort` method takes optional arguments for controlling the
+ comparisons.
+
+ *cmp* specifies a custom comparison function of two arguments (list items) which
+ should return a negative, zero or positive number depending on whether the first
+ argument is considered smaller than, equal to, or larger than the second
+ argument: ``cmp=lambda x,y: cmp(x.lower(), y.lower())``
+
+ *key* specifies a function of one argument that is used to extract a comparison
+ key from each list element: ``key=str.lower``
+
+ *reverse* is a boolean value. If set to ``True``, then the list elements are
+ sorted as if each comparison were reversed.
+
+ In general, the *key* and *reverse* conversion processes are much faster than
+ specifying an equivalent *cmp* function. This is because *cmp* is called
+ multiple times for each list element while *key* and *reverse* touch each
+ element only once.
+
+ .. versionchanged:: 2.3
+ Support for ``None`` as an equivalent to omitting *cmp* was added.
+
+ .. versionchanged:: 2.4
+ Support for *key* and *reverse* was added.
+
+(9)
+ Starting with Python 2.3, the :meth:`sort` method is guaranteed to be stable. A
+ sort is stable if it guarantees not to change the relative order of elements
+ that compare equal --- this is helpful for sorting in multiple passes (for
+ example, sort by department, then by salary grade).
+
+(10)
+ While a list is being sorted, the effect of attempting to mutate, or even
+ inspect, the list is undefined. The C implementation of Python 2.3 and newer
+ makes the list appear empty for the duration, and raises :exc:`ValueError` if it
+ can detect that the list has been mutated during a sort.
+
+
+.. _types-set:
+
+Set Types --- :class:`set`, :class:`frozenset`
+==============================================
+
+.. index:: object: set
+
+A :dfn:`set` object is an unordered collection of distinct hashable objects.
+Common uses include membership testing, removing duplicates from a sequence, and
+computing mathematical operations such as intersection, union, difference, and
+symmetric difference.
+(For other containers see the built in :class:`dict`, :class:`list`,
+and :class:`tuple` classes, and the :mod:`collections` module.)
+
+
+.. versionadded:: 2.4
+
+Like other collections, sets support ``x in set``, ``len(set)``, and ``for x in
+set``. Being an unordered collection, sets do not record element position or
+order of insertion. Accordingly, sets do not support indexing, slicing, or
+other sequence-like behavior.
+
+There are currently two builtin set types, :class:`set` and :class:`frozenset`.
+The :class:`set` type is mutable --- the contents can be changed using methods
+like :meth:`add` and :meth:`remove`. Since it is mutable, it has no hash value
+and cannot be used as either a dictionary key or as an element of another set.
+The :class:`frozenset` type is immutable and hashable --- its contents cannot be
+altered after it is created; it can therefore be used as a dictionary key or as
+an element of another set.
+
+The constructors for both classes work the same:
+
+.. class:: set([iterable])
+ frozenset([iterable])
+
+ Return a new set or frozenset object whose elements are taken from
+ *iterable*. The elements of a set must be hashable. To represent sets of
+ sets, the inner sets must be :class:`frozenset` objects. If *iterable* is
+ not specified, a new empty set is returned.
+
+Instances of :class:`set` and :class:`frozenset` provide the following
+operations:
+
+.. describe:: len(s)
+
+ Return the cardinality of set *s*.
+
+.. describe:: x in s
+
+ Test *x* for membership in *s*.
+
+.. describe:: x not in s
+
+ Test *x* for non-membership in *s*.
+
+.. method:: set.issubset(other)
+ set <= other
+
+ Test whether every element in the set is in *other*.
+
+.. method:: set.issuperset(other)
+ set >= other
+
+ Test whether every element in *other* is in the set.
+
+.. method:: set.union(other)
+ set | other
+
+ Return a new set with elements from both sets.
+
+.. method:: set.intersection(other)
+ set & other
+
+ Return a new set with elements common to both sets.
+
+.. method:: set.difference(other)
+ set - other
+
+ Return a new set with elements in the set that are not in *other*.
+
+.. method:: set.symmetric_difference(other)
+ set ^ other
+
+ Return a new set with elements in either the set or *other* but not both.
+
+.. method:: set.copy()
+
+ Return a new set with a shallow copy of *s*.
+
+
+Note, the non-operator versions of :meth:`union`, :meth:`intersection`,
+:meth:`difference`, and :meth:`symmetric_difference`, :meth:`issubset`, and
+:meth:`issuperset` methods will accept any iterable as an argument. In
+contrast, their operator based counterparts require their arguments to be sets.
+This precludes error-prone constructions like ``set('abc') & 'cbs'`` in favor of
+the more readable ``set('abc').intersection('cbs')``.
+
+Both :class:`set` and :class:`frozenset` support set to set comparisons. Two
+sets are equal if and only if every element of each set is contained in the
+other (each is a subset of the other). A set is less than another set if and
+only if the first set is a proper subset of the second set (is a subset, but is
+not equal). A set is greater than another set if and only if the first set is a
+proper superset of the second set (is a superset, but is not equal).
+
+Instances of :class:`set` are compared to instances of :class:`frozenset` based
+on their members. For example, ``set('abc') == frozenset('abc')`` returns
+``True``.
+
+The subset and equality comparisons do not generalize to a complete ordering
+function. For example, any two disjoint sets are not equal and are not subsets
+of each other, so *all* of the following return ``False``: ``a<b``, ``a==b``,
+or ``a>b``. Accordingly, sets do not implement the :meth:`__cmp__` method.
+
+Since sets only define partial ordering (subset relationships), the output of
+the :meth:`list.sort` method is undefined for lists of sets.
+
+Set elements are like dictionary keys; they need to define both :meth:`__hash__`
+and :meth:`__eq__` methods.
+
+Binary operations that mix :class:`set` instances with :class:`frozenset` return
+the type of the first operand. For example: ``frozenset('ab') | set('bc')``
+returns an instance of :class:`frozenset`.
+
+The following table lists operations available for :class:`set` that do not
+apply to immutable instances of :class:`frozenset`:
+
+.. method:: set.update(other)
+ set |= other
+
+ Update the set, adding elements from *other*.
+
+.. method:: set.intersection_update(other)
+ set &= other
+
+ Update the set, keeping only elements found in it and *other*.
+
+.. method:: set.difference_update(other)
+ set -= other
+
+ Update the set, removing elements found in *other*.
+
+.. method:: set.symmetric_difference_update(other)
+ set ^= other
+
+ Update the set, keeping only elements found in either set, but not in both.
+
+.. method:: set.add(el)
+
+ Add element *el* to the set.
+
+.. method:: set.remove(el)
+
+ Remove element *el* from the set. Raises :exc:`KeyError` if *el* is not
+ contained in the set.
+
+.. method:: set.discard(el)
+
+ Remove element *el* from the set if it is present.
+
+.. method:: set.pop()
+
+ Remove and return an arbitrary element from the set. Raises :exc:`KeyError`
+ if the set is empty.
+
+.. method:: set.clear()
+
+ Remove all elements from the set.
+
+
+Note, the non-operator versions of the :meth:`update`,
+:meth:`intersection_update`, :meth:`difference_update`, and
+:meth:`symmetric_difference_update` methods will accept any iterable as an
+argument.
+
+
+.. _typesmapping:
+
+Mapping Types --- :class:`dict`
+===============================
+
+.. index::
+ object: mapping
+ object: dictionary
+ triple: operations on; mapping; types
+ triple: operations on; dictionary; type
+ statement: del
+ builtin: len
+
+A :dfn:`mapping` object maps immutable values to arbitrary objects. Mappings
+are mutable objects. There is currently only one standard mapping type, the
+:dfn:`dictionary`.
+(For other containers see the built in :class:`list`,
+:class:`set`, and :class:`tuple` classes, and the :mod:`collections`
+module.)
+
+A dictionary's keys are *almost* arbitrary values. Only
+values containing lists, dictionaries or other mutable types (that are compared
+by value rather than by object identity) may not be used as keys. Numeric types
+used for keys obey the normal rules for numeric comparison: if two numbers
+compare equal (such as ``1`` and ``1.0``) then they can be used interchangeably
+to index the same dictionary entry. (Note however, that since computers
+store floating-point numbers as approximations it is usually unwise to
+use them as dictionary keys.)
+
+Dictionaries can be created by placing a comma-separated list of ``key: value``
+pairs within braces, for example: ``{'jack': 4098, 'sjoerd': 4127}`` or ``{4098:
+'jack', 4127: 'sjoerd'}``, or by the :class:`dict` constructor.
+
+.. class:: dict([arg])
+
+ Return a new dictionary initialized from an optional positional argument or from
+ a set of keyword arguments. If no arguments are given, return a new empty
+ dictionary. If the positional argument *arg* is a mapping object, return a
+ dictionary mapping the same keys to the same values as does the mapping object.
+ Otherwise the positional argument must be a sequence, a container that supports
+ iteration, or an iterator object. The elements of the argument must each also
+ be of one of those kinds, and each must in turn contain exactly two objects.
+ The first is used as a key in the new dictionary, and the second as the key's
+ value. If a given key is seen more than once, the last value associated with it
+ is retained in the new dictionary.
+
+ If keyword arguments are given, the keywords themselves with their associated
+ values are added as items to the dictionary. If a key is specified both in the
+ positional argument and as a keyword argument, the value associated with the
+ keyword is retained in the dictionary. For example, these all return a
+ dictionary equal to ``{"one": 2, "two": 3}``:
+
+ * ``dict(one=2, two=3)``
+
+ * ``dict({'one': 2, 'two': 3})``
+
+ * ``dict(zip(('one', 'two'), (2, 3)))``
+
+ * ``dict([['two', 3], ['one', 2]])``
+
+ The first example only works for keys that are valid Python
+ identifiers; the others work with any valid keys.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.3
+ Support for building a dictionary from keyword arguments added.
+
+
+These are the operations that dictionaries support (and therefore, custom mapping
+types should support too):
+
+.. describe:: len(d)
+
+ Return the number of items in the dictionary *d*.
+
+.. describe:: d[key]
+
+ Return the item of *d* with key *key*. Raises a :exc:`KeyError` if *key* is
+ not in the map.
+
+ .. versionadded:: 2.5
+ If a subclass of dict defines a method :meth:`__missing__`, if the key
+ *key* is not present, the ``d[key]`` operation calls that method with the
+ key *key* as argument. The ``d[key]`` operation then returns or raises
+ whatever is returned or raised by the ``__missing__(key)`` call if the key
+ is not present. No other operations or methods invoke
+ :meth:`__missing__`. If :meth:`__missing__` is not defined,
+ :exc:`KeyError` is raised. :meth:`__missing__` must be a method; it
+ cannot be an instance variable. For an example, see
+ :class:`collections.defaultdict`.
+
+.. describe:: d[key] = value
+
+ Set ``d[key]`` to *value*.
+
+.. describe:: del d[key]
+
+ Remove ``d[key]`` from *d*. Raises a :exc:`KeyError` if *key* is not in the
+ map.
+
+.. describe:: key in d
+
+ Return ``True`` if *d* has a key *key*, else ``False``.
+
+ .. versionadded:: 2.2
+
+.. describe:: key not in d
+
+ Equivalent to ``not key in d``.
+
+ .. versionadded:: 2.2
+
+.. method:: dict.clear()
+
+ Remove all items from the dictionary.
+
+.. method:: dict.copy()
+
+ Return a shallow copy of the dictionary.
+
+.. method:: dict.fromkeys(seq[, value])
+
+ Create a new dictionary with keys from *seq* and values set to *value*.
+
+ :func:`fromkeys` is a class method that returns a new dictionary. *value*
+ defaults to ``None``.
+
+ .. versionadded:: 2.3
+
+.. method:: dict.get(key[, default])
+
+ Return the value for *key* if *key* is in the dictionary, else *default*. If
+ *default* is not given, it defaults to ``None``, so that this method never
+ raises a :exc:`KeyError`.
+
+.. method:: dict.has_key(key)
+
+ ``d.has_key(key)`` is equivalent to ``key in d``, but deprecated.
+
+.. method:: dict.items()
+
+ Return a copy of the dictionary's list of ``(key, value)`` pairs.
+
+ .. note::
+
+ Keys and values are listed in an arbitrary order which is non-random, varies
+ across Python implementations, and depends on the dictionary's history of
+ insertions and deletions. If :meth:`items`, :meth:`keys`, :meth:`values`,
+ :meth:`iteritems`, :meth:`iterkeys`, and :meth:`itervalues` are called with no
+ intervening modifications to the dictionary, the lists will directly correspond.
+ This allows the creation of ``(value, key)`` pairs using :func:`zip`: ``pairs =
+ zip(d.values(), d.keys())``. The same relationship holds for the
+ :meth:`iterkeys` and :meth:`itervalues` methods: ``pairs = zip(d.itervalues(),
+ d.iterkeys())`` provides the same value for ``pairs``. Another way to create the
+ same list is ``pairs = [(v, k) for (k, v) in d.iteritems()]``.
+
+.. method:: dict.iteritems()
+
+ Return an iterator over the dictionary's ``(key, value)`` pairs.
+ See the note for :meth:`dict.items`.
+
+ .. versionadded:: 2.2
+
+.. method:: dict.iterkeys()
+
+ Return an iterator over the dictionary's keys. See the note for
+ :meth:`dict.items`.
+
+ .. versionadded:: 2.2
+
+.. method:: dict.itervalues()
+
+ Return an iterator over the dictionary's values. See the note for
+ :meth:`dict.items`.
+
+ .. versionadded:: 2.2
+
+.. method:: dict.keys()
+
+ Return a copy of the dictionary's list of keys. See the note for
+ :meth:`dict.items`.
+
+.. method:: dict.pop(key[, default])
+
+ If *key* is in the dictionary, remove it and return its value, else return
+ *default*. If *default* is not given and *key* is not in the dictionary, a
+ :exc:`KeyError` is raised.
+
+ .. versionadded:: 2.3
+
+.. method:: dict.popitem()
+
+ Remove and return an arbitrary ``(key, value)`` pair from the dictionary.
+
+ :func:`popitem` is useful to destructively iterate over a dictionary, as
+ often used in set algorithms. If the dictionary is empty, calling
+ :func:`popitem` raises a :exc:`KeyError`.
+
+.. method:: dict.setdefault(key[, default])
+
+ If *key* is in the dictionary, return its value. If not, insert *key* with a
+ value of *default* and return *default*. *default* defaults to ``None``.
+
+.. method:: dict.update([other])
+
+ Update the dictionary with the key/value pairs from *other*, overwriting existing
+ keys. Return ``None``.
+
+ :func:`update` accepts either another dictionary object or an iterable of
+ key/value pairs (as a tuple or other iterable of length two). If keyword
+ arguments are specified, the dictionary is then is updated with those
+ key/value pairs: ``d.update(red=1, blue=2)``.
+
+ .. versionchanged:: 2.4
+ Allowed the argument to be an iterable of key/value pairs and allowed
+ keyword arguments.
+
+.. method:: dict.values()
+
+ Return a copy of the dictionary's list of values. See the note for
+ :meth:`mapping.items`.
+
+
+.. _bltin-file-objects:
+
+File Objects
+============
+
+.. index::
+ object: file
+ builtin: file
+ module: os
+ module: socket
+
+File objects are implemented using C's ``stdio`` package and can be
+created with the built-in :func:`file` and (more usually) :func:`open`
+constructors described in the :ref:`built-in-funcs` section. [#]_ File
+objects are also returned by some other built-in functions and methods,
+such as :func:`os.popen` and :func:`os.fdopen` and the :meth:`makefile`
+method of socket objects.
+
+When a file operation fails for an I/O-related reason, the exception
+:exc:`IOError` is raised. This includes situations where the operation is not
+defined for some reason, like :meth:`seek` on a tty device or writing a file
+opened for reading.
+
+Files have the following methods:
+
+
+.. method:: file.close()
+
+ Close the file. A closed file cannot be read or written any more. Any operation
+ which requires that the file be open will raise a :exc:`ValueError` after the
+ file has been closed. Calling :meth:`close` more than once is allowed.
+
+ As of Python 2.5, you can avoid having to call this method explicitly if you use
+ the :keyword:`with` statement. For example, the following code will
+ automatically close ``f`` when the :keyword:`with` block is exited::
+
+ from __future__ import with_statement
+
+ with open("hello.txt") as f:
+ for line in f:
+ print line
+
+ In older versions of Python, you would have needed to do this to get the same
+ effect::
+
+ f = open("hello.txt")
+ try:
+ for line in f:
+ print line
+ finally:
+ f.close()
+
+ .. note::
+
+ Not all "file-like" types in Python support use as a context manager for the
+ :keyword:`with` statement. If your code is intended to work with any file-like
+ object, you can use the function :func:`contextlib.closing` instead of using
+ the object directly.
+
+
+.. method:: file.flush()
+
+ Flush the internal buffer, like ``stdio``'s :cfunc:`fflush`. This may be a
+ no-op on some file-like objects.
+
+
+.. method:: file.fileno()
+
+ .. index::
+ single: file descriptor
+ single: descriptor, file
+ module: fcntl
+
+ Return the integer "file descriptor" that is used by the underlying
+ implementation to request I/O operations from the operating system. This can be
+ useful for other, lower level interfaces that use file descriptors, such as the
+ :mod:`fcntl` module or :func:`os.read` and friends.
+
+ .. note::
+
+ File-like objects which do not have a real file descriptor should *not* provide
+ this method!
+
+
+.. method:: file.isatty()
+
+ Return ``True`` if the file is connected to a tty(-like) device, else ``False``.
+
+ .. note::
+
+ If a file-like object is not associated with a real file, this method should
+ *not* be implemented.
+
+
+.. method:: file.__next__()
+
+ A file object is its own iterator, for example ``iter(f)`` returns *f* (unless
+ *f* is closed). When a file is used as an iterator, typically in a
+ :keyword:`for` loop (for example, ``for line in f: print line``), the
+ :meth:`__next__` method is called repeatedly. This method returns the next
+ input line, or raises :exc:`StopIteration` when EOF is hit when the file is open
+ for reading (behavior is undefined when the file is open for writing). In order
+ to make a :keyword:`for` loop the most efficient way of looping over the lines
+ of a file (a very common operation), the :meth:`__next__` method uses a hidden
+ read-ahead buffer. As a consequence of using a read-ahead buffer, combining
+ :meth:`__next__` with other file methods (like :meth:`readline`) does not work
+ right. However, using :meth:`seek` to reposition the file to an absolute
+ position will flush the read-ahead buffer.
+
+ .. versionadded:: 2.3
+
+
+.. method:: file.read([size])
+
+ Read at most *size* bytes from the file (less if the read hits EOF before
+ obtaining *size* bytes). If the *size* argument is negative or omitted, read
+ all data until EOF is reached. The bytes are returned as a string object. An
+ empty string is returned when EOF is encountered immediately. (For certain
+ files, like ttys, it makes sense to continue reading after an EOF is hit.) Note
+ that this method may call the underlying C function :cfunc:`fread` more than
+ once in an effort to acquire as close to *size* bytes as possible. Also note
+ that when in non-blocking mode, less data than what was requested may be
+ returned, even if no *size* parameter was given.
+
+
+.. method:: file.readline([size])
+
+ Read one entire line from the file. A trailing newline character is kept in the
+ string (but may be absent when a file ends with an incomplete line). [#]_ If
+ the *size* argument is present and non-negative, it is a maximum byte count
+ (including the trailing newline) and an incomplete line may be returned. An
+ empty string is returned *only* when EOF is encountered immediately.
+
+ .. note::
+
+ Unlike ``stdio``'s :cfunc:`fgets`, the returned string contains null characters
+ (``'\0'``) if they occurred in the input.
+
+
+.. method:: file.readlines([sizehint])
+
+ Read until EOF using :meth:`readline` and return a list containing the lines
+ thus read. If the optional *sizehint* argument is present, instead of
+ reading up to EOF, whole lines totalling approximately *sizehint* bytes
+ (possibly after rounding up to an internal buffer size) are read. Objects
+ implementing a file-like interface may choose to ignore *sizehint* if it
+ cannot be implemented, or cannot be implemented efficiently.
+
+
+.. method:: file.seek(offset[, whence])
+
+ Set the file's current position, like ``stdio``'s :cfunc:`fseek`. The *whence*
+ argument is optional and defaults to ``os.SEEK_SET`` or ``0`` (absolute file
+ positioning); other values are ``os.SEEK_CUR`` or ``1`` (seek relative to the
+ current position) and ``os.SEEK_END`` or ``2`` (seek relative to the file's
+ end). There is no return value. Note that if the file is opened for appending
+ (mode ``'a'`` or ``'a+'``), any :meth:`seek` operations will be undone at the
+ next write. If the file is only opened for writing in append mode (mode
+ ``'a'``), this method is essentially a no-op, but it remains useful for files
+ opened in append mode with reading enabled (mode ``'a+'``). If the file is
+ opened in text mode (without ``'b'``), only offsets returned by :meth:`tell` are
+ legal. Use of other offsets causes undefined behavior.
+
+ Note that not all file objects are seekable.
+
+ .. versionchanged:: 2.6
+ Passing float values as offset has been deprecated
+
+
+.. method:: file.tell()
+
+ Return the file's current position, like ``stdio``'s :cfunc:`ftell`.
+
+ .. note::
+
+ On Windows, :meth:`tell` can return illegal values (after an :cfunc:`fgets`)
+ when reading files with Unix-style line-endings. Use binary mode (``'rb'``) to
+ circumvent this problem.
+
+
+.. method:: file.truncate([size])
+
+ Truncate the file's size. If the optional *size* argument is present, the file
+ is truncated to (at most) that size. The size defaults to the current position.
+ The current file position is not changed. Note that if a specified size exceeds
+ the file's current size, the result is platform-dependent: possibilities
+ include that the file may remain unchanged, increase to the specified size as if
+ zero-filled, or increase to the specified size with undefined new content.
+ Availability: Windows, many Unix variants.
+
+
+.. method:: file.write(str)
+
+ Write a string to the file. There is no return value. Due to buffering, the
+ string may not actually show up in the file until the :meth:`flush` or
+ :meth:`close` method is called.
+
+
+.. method:: file.writelines(sequence)
+
+ Write a sequence of strings to the file. The sequence can be any iterable
+ object producing strings, typically a list of strings. There is no return value.
+ (The name is intended to match :meth:`readlines`; :meth:`writelines` does not
+ add line separators.)
+
+Files support the iterator protocol. Each iteration returns the same result as
+``file.readline()``, and iteration ends when the :meth:`readline` method returns
+an empty string.
+
+File objects also offer a number of other interesting attributes. These are not
+required for file-like objects, but should be implemented if they make sense for
+the particular object.
+
+
+.. attribute:: file.closed
+
+ bool indicating the current state of the file object. This is a read-only
+ attribute; the :meth:`close` method changes the value. It may not be available
+ on all file-like objects.
+
+
+.. attribute:: file.encoding
+
+ The encoding that this file uses. When Unicode strings are written to a file,
+ they will be converted to byte strings using this encoding. In addition, when
+ the file is connected to a terminal, the attribute gives the encoding that the
+ terminal is likely to use (that information might be incorrect if the user has
+ misconfigured the terminal). The attribute is read-only and may not be present
+ on all file-like objects. It may also be ``None``, in which case the file uses
+ the system default encoding for converting Unicode strings.
+
+ .. versionadded:: 2.3
+
+
+.. attribute:: file.mode
+
+ The I/O mode for the file. If the file was created using the :func:`open`
+ built-in function, this will be the value of the *mode* parameter. This is a
+ read-only attribute and may not be present on all file-like objects.
+
+
+.. attribute:: file.name
+
+ If the file object was created using :func:`open`, the name of the file.
+ Otherwise, some string that indicates the source of the file object, of the
+ form ``<...>``. This is a read-only attribute and may not be present on all
+ file-like objects.
+
+
+.. attribute:: file.newlines
+
+ If Python was built with the :option:`--with-universal-newlines` option to
+ :program:`configure` (the default) this read-only attribute exists, and for
+ files opened in universal newline read mode it keeps track of the types of
+ newlines encountered while reading the file. The values it can take are
+ ``'\r'``, ``'\n'``, ``'\r\n'``, ``None`` (unknown, no newlines read yet) or a
+ tuple containing all the newline types seen, to indicate that multiple newline
+ conventions were encountered. For files not opened in universal newline read
+ mode the value of this attribute will be ``None``.
+
+
+.. attribute:: file.softspace
+
+ Boolean that indicates whether a space character needs to be printed before
+ another value when using the :keyword:`print` statement. Classes that are trying
+ to simulate a file object should also have a writable :attr:`softspace`
+ attribute, which should be initialized to zero. This will be automatic for most
+ classes implemented in Python (care may be needed for objects that override
+ attribute access); types implemented in C will have to provide a writable
+ :attr:`softspace` attribute.
+
+ .. note::
+
+ This attribute is not used to control the :keyword:`print` statement, but to
+ allow the implementation of :keyword:`print` to keep track of its internal
+ state.
+
+
+.. _typecontextmanager:
+
+Context Manager Types
+=====================
+
+.. versionadded:: 2.5
+
+.. index::
+ single: context manager
+ single: context management protocol
+ single: protocol; context management
+
+Python's :keyword:`with` statement supports the concept of a runtime context
+defined by a context manager. This is implemented using two separate methods
+that allow user-defined classes to define a runtime context that is entered
+before the statement body is executed and exited when the statement ends.
+
+The :dfn:`context management protocol` consists of a pair of methods that need
+to be provided for a context manager object to define a runtime context:
+
+
+.. method:: contextmanager.__enter__()
+
+ Enter the runtime context and return either this object or another object
+ related to the runtime context. The value returned by this method is bound to
+ the identifier in the :keyword:`as` clause of :keyword:`with` statements using
+ this context manager.
+
+ An example of a context manager that returns itself is a file object. File
+ objects return themselves from __enter__() to allow :func:`open` to be used as
+ the context expression in a :keyword:`with` statement.
+
+ An example of a context manager that returns a related object is the one
+ returned by ``decimal.Context.get_manager()``. These managers set the active
+ decimal context to a copy of the original decimal context and then return the
+ copy. This allows changes to be made to the current decimal context in the body
+ of the :keyword:`with` statement without affecting code outside the
+ :keyword:`with` statement.
+
+
+.. method:: contextmanager.__exit__(exc_type, exc_val, exc_tb)
+
+ Exit the runtime context and return a Boolean flag indicating if any expection
+ that occurred should be suppressed. If an exception occurred while executing the
+ body of the :keyword:`with` statement, the arguments contain the exception type,
+ value and traceback information. Otherwise, all three arguments are ``None``.
+
+ Returning a true value from this method will cause the :keyword:`with` statement
+ to suppress the exception and continue execution with the statement immediately
+ following the :keyword:`with` statement. Otherwise the exception continues
+ propagating after this method has finished executing. Exceptions that occur
+ during execution of this method will replace any exception that occurred in the
+ body of the :keyword:`with` statement.
+
+ The exception passed in should never be reraised explicitly - instead, this
+ method should return a false value to indicate that the method completed
+ successfully and does not want to suppress the raised exception. This allows
+ context management code (such as ``contextlib.nested``) to easily detect whether
+ or not an :meth:`__exit__` method has actually failed.
+
+Python defines several context managers to support easy thread synchronisation,
+prompt closure of files or other objects, and simpler manipulation of the active
+decimal arithmetic context. The specific types are not treated specially beyond
+their implementation of the context management protocol. See the
+:mod:`contextlib` module for some examples.
+
+Python's generators and the ``contextlib.contextfactory`` decorator provide a
+convenient way to implement these protocols. If a generator function is
+decorated with the ``contextlib.contextfactory`` decorator, it will return a
+context manager implementing the necessary :meth:`__enter__` and
+:meth:`__exit__` methods, rather than the iterator produced by an undecorated
+generator function.
+
+Note that there is no specific slot for any of these methods in the type
+structure for Python objects in the Python/C API. Extension types wanting to
+define these methods must provide them as a normal Python accessible method.
+Compared to the overhead of setting up the runtime context, the overhead of a
+single class dictionary lookup is negligible.
+
+
+.. _typesother:
+
+Other Built-in Types
+====================
+
+The interpreter supports several other kinds of objects. Most of these support
+only one or two operations.
+
+
+.. _typesmodules:
+
+Modules
+-------
+
+The only special operation on a module is attribute access: ``m.name``, where
+*m* is a module and *name* accesses a name defined in *m*'s symbol table.
+Module attributes can be assigned to. (Note that the :keyword:`import`
+statement is not, strictly speaking, an operation on a module object; ``import
+foo`` does not require a module object named *foo* to exist, rather it requires
+an (external) *definition* for a module named *foo* somewhere.)
+
+A special member of every module is :attr:`__dict__`. This is the dictionary
+containing the module's symbol table. Modifying this dictionary will actually
+change the module's symbol table, but direct assignment to the :attr:`__dict__`
+attribute is not possible (you can write ``m.__dict__['a'] = 1``, which defines
+``m.a`` to be ``1``, but you can't write ``m.__dict__ = {}``). Modifying
+:attr:`__dict__` directly is not recommended.
+
+Modules built into the interpreter are written like this: ``<module 'sys'
+(built-in)>``. If loaded from a file, they are written as ``<module 'os' from
+'/usr/local/lib/pythonX.Y/os.pyc'>``.
+
+
+.. _typesobjects:
+
+Classes and Class Instances
+---------------------------
+
+See :ref:`objects` and :ref:`class` for these.
+
+
+.. _typesfunctions:
+
+Functions
+---------
+
+Function objects are created by function definitions. The only operation on a
+function object is to call it: ``func(argument-list)``.
+
+There are really two flavors of function objects: built-in functions and
+user-defined functions. Both support the same operation (to call the function),
+but the implementation is different, hence the different object types.
+
+See :ref:`function` for more information.
+
+
+.. _typesmethods:
+
+Methods
+-------
+
+.. index:: object: method
+
+Methods are functions that are called using the attribute notation. There are
+two flavors: built-in methods (such as :meth:`append` on lists) and class
+instance methods. Built-in methods are described with the types that support
+them.
+
+The implementation adds two special read-only attributes to class instance
+methods: ``m.im_self`` is the object on which the method operates, and
+``m.im_func`` is the function implementing the method. Calling ``m(arg-1,
+arg-2, ..., arg-n)`` is completely equivalent to calling ``m.im_func(m.im_self,
+arg-1, arg-2, ..., arg-n)``.
+
+Class instance methods are either *bound* or *unbound*, referring to whether the
+method was accessed through an instance or a class, respectively. When a method
+is unbound, its ``im_self`` attribute will be ``None`` and if called, an
+explicit ``self`` object must be passed as the first argument. In this case,
+``self`` must be an instance of the unbound method's class (or a subclass of
+that class), otherwise a :exc:`TypeError` is raised.
+
+Like function objects, methods objects support getting arbitrary attributes.
+However, since method attributes are actually stored on the underlying function
+object (``meth.im_func``), setting method attributes on either bound or unbound
+methods is disallowed. Attempting to set a method attribute results in a
+:exc:`TypeError` being raised. In order to set a method attribute, you need to
+explicitly set it on the underlying function object::
+
+ class C:
+ def method(self):
+ pass
+
+ c = C()
+ c.method.im_func.whoami = 'my name is c'
+
+See :ref:`types` for more information.
+
+
+.. _bltin-code-objects:
+
+Code Objects
+------------
+
+.. index:: object: code
+
+.. index::
+ builtin: compile
+ single: __code__ (function object attribute)
+
+Code objects are used by the implementation to represent "pseudo-compiled"
+executable Python code such as a function body. They differ from function
+objects because they don't contain a reference to their global execution
+environment. Code objects are returned by the built-in :func:`compile` function
+and can be extracted from function objects through their :attr:`__code__`
+attribute. See also the :mod:`code` module.
+
+.. index::
+ builtin: exec
+ builtin: eval
+
+A code object can be executed or evaluated by passing it (instead of a source
+string) to the :func:`exec` or :func:`eval` built-in functions.
+
+See :ref:`types` for more information.
+
+
+.. _bltin-type-objects:
+
+Type Objects
+------------
+
+.. index::
+ builtin: type
+ module: types
+
+Type objects represent the various object types. An object's type is accessed
+by the built-in function :func:`type`. There are no special operations on
+types. The standard module :mod:`types` defines names for all standard built-in
+types.
+
+Types are written like this: ``<type 'int'>``.
+
+
+.. _bltin-null-object:
+
+The Null Object
+---------------
+
+This object is returned by functions that don't explicitly return a value. It
+supports no special operations. There is exactly one null object, named
+``None`` (a built-in name).
+
+It is written as ``None``.
+
+
+.. _bltin-ellipsis-object:
+
+The Ellipsis Object
+-------------------
+
+This object is mostly used by extended slice notation (see :ref:`slicings`). It
+supports no special operations. There is exactly one ellipsis object, named
+:const:`Ellipsis` (a built-in name).
+
+It is written as ``Ellipsis`` or ``...``.
+
+
+Boolean Values
+--------------
+
+Boolean values are the two constant objects ``False`` and ``True``. They are
+used to represent truth values (although other values can also be considered
+false or true). In numeric contexts (for example when used as the argument to
+an arithmetic operator), they behave like the integers 0 and 1, respectively.
+The built-in function :func:`bool` can be used to cast any value to a Boolean,
+if the value can be interpreted as a truth value (see section Truth Value
+Testing above).
+
+.. index::
+ single: False
+ single: True
+ pair: Boolean; values
+
+They are written as ``False`` and ``True``, respectively.
+
+
+.. _typesinternal:
+
+Internal Objects
+----------------
+
+See :ref:`types` for this information. It describes stack frame objects,
+traceback objects, and slice objects.
+
+
+.. _specialattrs:
+
+Special Attributes
+==================
+
+The implementation adds a few special read-only attributes to several object
+types, where they are relevant. Some of these are not reported by the
+:func:`dir` built-in function.
+
+
+.. attribute:: object.__dict__
+
+ A dictionary or other mapping object used to store an object's (writable)
+ attributes.
+
+
+.. attribute:: instance.__class__
+
+ The class to which a class instance belongs.
+
+
+.. attribute:: class.__bases__
+
+ The tuple of base classes of a class object. If there are no base classes, this
+ will be an empty tuple.
+
+
+.. attribute:: class.__name__
+
+ The name of the class or type.
+
+.. rubric:: Footnotes
+
+.. [#] Additional information on these special methods may be found in the Python
+ Reference Manual (:ref:`customization`).
+
+.. [#] As a consequence, the list ``[1, 2]`` is considered equal to ``[1.0, 2.0]``, and
+ similarly for tuples.
+
+.. [#] They must have since the parser can't tell the type of the operands.
+
+.. [#] To format only a tuple you should therefore provide a singleton tuple whose only
+ element is the tuple to be formatted.
+
+.. [#] These numbers are fairly arbitrary. They are intended to avoid printing endless
+ strings of meaningless digits without hampering correct use and without having
+ to know the exact precision of floating point values on a particular machine.
+
+.. [#] :func:`file` is new in Python 2.2. The older built-in :func:`open` is an alias
+ for :func:`file`.
+
+.. [#] The advantage of leaving the newline on is that returning an empty string is
+ then an unambiguous EOF indication. It is also possible (in cases where it
+ might matter, for example, if you want to make an exact copy of a file while
+ scanning its lines) to tell whether the last line of a file ended in a newline
+ or not (yes this happens!).
diff --git a/Doc/library/string.rst b/Doc/library/string.rst
new file mode 100644
index 0000000000..aa2494b888
--- /dev/null
+++ b/Doc/library/string.rst
@@ -0,0 +1,468 @@
+
+:mod:`string` --- Common string operations
+==========================================
+
+.. module:: string
+ :synopsis: Common string operations.
+
+
+.. index:: module: re
+
+The :mod:`string` module contains a number of useful constants and
+classes, as well as some deprecated legacy functions that are also
+available as methods on strings. In addition, Python's built-in string
+classes support the sequence type methods described in the
+:ref:`typesseq` section, and also the string-specific methods described
+in the :ref:`string-methods` section. To output formatted strings use
+template strings or the ``%`` operator described in the
+:ref:`string-formatting` section. Also, see the :mod:`re` module for
+string functions based on regular expressions.
+
+
+String constants
+----------------
+
+The constants defined in this module are:
+
+
+.. data:: ascii_letters
+
+ The concatenation of the :const:`ascii_lowercase` and :const:`ascii_uppercase`
+ constants described below. This value is not locale-dependent.
+
+
+.. data:: ascii_lowercase
+
+ The lowercase letters ``'abcdefghijklmnopqrstuvwxyz'``. This value is not
+ locale-dependent and will not change.
+
+
+.. data:: ascii_uppercase
+
+ The uppercase letters ``'ABCDEFGHIJKLMNOPQRSTUVWXYZ'``. This value is not
+ locale-dependent and will not change.
+
+
+.. data:: digits
+
+ The string ``'0123456789'``.
+
+
+.. data:: hexdigits
+
+ The string ``'0123456789abcdefABCDEF'``.
+
+
+.. data:: octdigits
+
+ The string ``'01234567'``.
+
+
+.. data:: punctuation
+
+ String of ASCII characters which are considered punctuation characters
+ in the ``C`` locale.
+
+
+.. data:: printable
+
+ String of ASCII characters which are considered printable. This is a
+ combination of :const:`digits`, :const:`ascii_letters`, :const:`punctuation`,
+ and :const:`whitespace`.
+
+
+.. data:: whitespace
+
+ A string containing all characters that are considered whitespace.
+ This includes the characters space, tab, linefeed, return, formfeed, and
+ vertical tab.
+
+
+Template strings
+----------------
+
+Templates provide simpler string substitutions as described in :pep:`292`.
+Instead of the normal ``%``\ -based substitutions, Templates support ``$``\
+-based substitutions, using the following rules:
+
+* ``$$`` is an escape; it is replaced with a single ``$``.
+
+* ``$identifier`` names a substitution placeholder matching a mapping key of
+ ``"identifier"``. By default, ``"identifier"`` must spell a Python
+ identifier. The first non-identifier character after the ``$`` character
+ terminates this placeholder specification.
+
+* ``${identifier}`` is equivalent to ``$identifier``. It is required when valid
+ identifier characters follow the placeholder but are not part of the
+ placeholder, such as ``"${noun}ification"``.
+
+Any other appearance of ``$`` in the string will result in a :exc:`ValueError`
+being raised.
+
+.. versionadded:: 2.4
+
+The :mod:`string` module provides a :class:`Template` class that implements
+these rules. The methods of :class:`Template` are:
+
+
+.. class:: Template(template)
+
+ The constructor takes a single argument which is the template string.
+
+
+.. method:: Template.substitute(mapping[, **kws])
+
+ Performs the template substitution, returning a new string. *mapping* is any
+ dictionary-like object with keys that match the placeholders in the template.
+ Alternatively, you can provide keyword arguments, where the keywords are the
+ placeholders. When both *mapping* and *kws* are given and there are duplicates,
+ the placeholders from *kws* take precedence.
+
+
+.. method:: Template.safe_substitute(mapping[, **kws])
+
+ Like :meth:`substitute`, except that if placeholders are missing from *mapping*
+ and *kws*, instead of raising a :exc:`KeyError` exception, the original
+ placeholder will appear in the resulting string intact. Also, unlike with
+ :meth:`substitute`, any other appearances of the ``$`` will simply return ``$``
+ instead of raising :exc:`ValueError`.
+
+ While other exceptions may still occur, this method is called "safe" because
+ substitutions always tries to return a usable string instead of raising an
+ exception. In another sense, :meth:`safe_substitute` may be anything other than
+ safe, since it will silently ignore malformed templates containing dangling
+ delimiters, unmatched braces, or placeholders that are not valid Python
+ identifiers.
+
+:class:`Template` instances also provide one public data attribute:
+
+
+.. attribute:: string.template
+
+ This is the object passed to the constructor's *template* argument. In general,
+ you shouldn't change it, but read-only access is not enforced.
+
+Here is an example of how to use a Template::
+
+ >>> from string import Template
+ >>> s = Template('$who likes $what')
+ >>> s.substitute(who='tim', what='kung pao')
+ 'tim likes kung pao'
+ >>> d = dict(who='tim')
+ >>> Template('Give $who $100').substitute(d)
+ Traceback (most recent call last):
+ [...]
+ ValueError: Invalid placeholder in string: line 1, col 10
+ >>> Template('$who likes $what').substitute(d)
+ Traceback (most recent call last):
+ [...]
+ KeyError: 'what'
+ >>> Template('$who likes $what').safe_substitute(d)
+ 'tim likes $what'
+
+Advanced usage: you can derive subclasses of :class:`Template` to customize the
+placeholder syntax, delimiter character, or the entire regular expression used
+to parse template strings. To do this, you can override these class attributes:
+
+* *delimiter* -- This is the literal string describing a placeholder introducing
+ delimiter. The default value ``$``. Note that this should *not* be a regular
+ expression, as the implementation will call :meth:`re.escape` on this string as
+ needed.
+
+* *idpattern* -- This is the regular expression describing the pattern for
+ non-braced placeholders (the braces will be added automatically as
+ appropriate). The default value is the regular expression
+ ``[_a-z][_a-z0-9]*``.
+
+Alternatively, you can provide the entire regular expression pattern by
+overriding the class attribute *pattern*. If you do this, the value must be a
+regular expression object with four named capturing groups. The capturing
+groups correspond to the rules given above, along with the invalid placeholder
+rule:
+
+* *escaped* -- This group matches the escape sequence, e.g. ``$$``, in the
+ default pattern.
+
+* *named* -- This group matches the unbraced placeholder name; it should not
+ include the delimiter in capturing group.
+
+* *braced* -- This group matches the brace enclosed placeholder name; it should
+ not include either the delimiter or braces in the capturing group.
+
+* *invalid* -- This group matches any other delimiter pattern (usually a single
+ delimiter), and it should appear last in the regular expression.
+
+
+String functions
+----------------
+
+The following functions are available to operate on string and Unicode objects.
+They are not available as string methods.
+
+
+.. function:: capwords(s)
+
+ Split the argument into words using :func:`split`, capitalize each word using
+ :func:`capitalize`, and join the capitalized words using :func:`join`. Note
+ that this replaces runs of whitespace characters by a single space, and removes
+ leading and trailing whitespace.
+
+
+.. function:: maketrans(from, to)
+
+ Return a translation table suitable for passing to :func:`translate`, that will
+ map each character in *from* into the character at the same position in *to*;
+ *from* and *to* must have the same length.
+
+ .. warning::
+
+ Don't use strings derived from :const:`lowercase` and :const:`uppercase` as
+ arguments; in some locales, these don't have the same length. For case
+ conversions, always use :func:`lower` and :func:`upper`.
+
+
+Deprecated string functions
+---------------------------
+
+The following list of functions are also defined as methods of string and
+Unicode objects; see section :ref:`string-methods` for more information on
+those. You should consider these functions as deprecated, although they will
+not be removed until Python 3.0. The functions defined in this module are:
+
+
+.. function:: atof(s)
+
+ .. deprecated:: 2.0
+ Use the :func:`float` built-in function.
+
+ .. index:: builtin: float
+
+ Convert a string to a floating point number. The string must have the standard
+ syntax for a floating point literal in Python, optionally preceded by a sign
+ (``+`` or ``-``). Note that this behaves identical to the built-in function
+ :func:`float` when passed a string.
+
+ .. note::
+
+ .. index::
+ single: NaN
+ single: Infinity
+
+ When passing in a string, values for NaN and Infinity may be returned, depending
+ on the underlying C library. The specific set of strings accepted which cause
+ these values to be returned depends entirely on the C library and is known to
+ vary.
+
+
+.. function:: atoi(s[, base])
+
+ .. deprecated:: 2.0
+ Use the :func:`int` built-in function.
+
+ .. index:: builtin: eval
+
+ Convert string *s* to an integer in the given *base*. The string must consist
+ of one or more digits, optionally preceded by a sign (``+`` or ``-``). The
+ *base* defaults to 10. If it is 0, a default base is chosen depending on the
+ leading characters of the string (after stripping the sign): ``0x`` or ``0X``
+ means 16, ``0`` means 8, anything else means 10. If *base* is 16, a leading
+ ``0x`` or ``0X`` is always accepted, though not required. This behaves
+ identically to the built-in function :func:`int` when passed a string. (Also
+ note: for a more flexible interpretation of numeric literals, use the built-in
+ function :func:`eval`.)
+
+
+.. function:: atol(s[, base])
+
+ .. deprecated:: 2.0
+ Use the :func:`long` built-in function.
+
+ .. index:: builtin: long
+
+ Convert string *s* to a long integer in the given *base*. The string must
+ consist of one or more digits, optionally preceded by a sign (``+`` or ``-``).
+ The *base* argument has the same meaning as for :func:`atoi`. A trailing ``l``
+ or ``L`` is not allowed, except if the base is 0. Note that when invoked
+ without *base* or with *base* set to 10, this behaves identical to the built-in
+ function :func:`long` when passed a string.
+
+
+.. function:: capitalize(word)
+
+ Return a copy of *word* with only its first character capitalized.
+
+
+.. function:: expandtabs(s[, tabsize])
+
+ Expand tabs in a string replacing them by one or more spaces, depending on the
+ current column and the given tab size. The column number is reset to zero after
+ each newline occurring in the string. This doesn't understand other non-printing
+ characters or escape sequences. The tab size defaults to 8.
+
+
+.. function:: find(s, sub[, start[,end]])
+
+ Return the lowest index in *s* where the substring *sub* is found such that
+ *sub* is wholly contained in ``s[start:end]``. Return ``-1`` on failure.
+ Defaults for *start* and *end* and interpretation of negative values is the same
+ as for slices.
+
+
+.. function:: rfind(s, sub[, start[, end]])
+
+ Like :func:`find` but find the highest index.
+
+
+.. function:: index(s, sub[, start[, end]])
+
+ Like :func:`find` but raise :exc:`ValueError` when the substring is not found.
+
+
+.. function:: rindex(s, sub[, start[, end]])
+
+ Like :func:`rfind` but raise :exc:`ValueError` when the substring is not found.
+
+
+.. function:: count(s, sub[, start[, end]])
+
+ Return the number of (non-overlapping) occurrences of substring *sub* in string
+ ``s[start:end]``. Defaults for *start* and *end* and interpretation of negative
+ values are the same as for slices.
+
+
+.. function:: lower(s)
+
+ Return a copy of *s*, but with upper case letters converted to lower case.
+
+
+.. function:: split(s[, sep[, maxsplit]])
+
+ Return a list of the words of the string *s*. If the optional second argument
+ *sep* is absent or ``None``, the words are separated by arbitrary strings of
+ whitespace characters (space, tab, newline, return, formfeed). If the second
+ argument *sep* is present and not ``None``, it specifies a string to be used as
+ the word separator. The returned list will then have one more item than the
+ number of non-overlapping occurrences of the separator in the string. The
+ optional third argument *maxsplit* defaults to 0. If it is nonzero, at most
+ *maxsplit* number of splits occur, and the remainder of the string is returned
+ as the final element of the list (thus, the list will have at most
+ ``maxsplit+1`` elements).
+
+ The behavior of split on an empty string depends on the value of *sep*. If *sep*
+ is not specified, or specified as ``None``, the result will be an empty list.
+ If *sep* is specified as any string, the result will be a list containing one
+ element which is an empty string.
+
+
+.. function:: rsplit(s[, sep[, maxsplit]])
+
+ Return a list of the words of the string *s*, scanning *s* from the end. To all
+ intents and purposes, the resulting list of words is the same as returned by
+ :func:`split`, except when the optional third argument *maxsplit* is explicitly
+ specified and nonzero. When *maxsplit* is nonzero, at most *maxsplit* number of
+ splits -- the *rightmost* ones -- occur, and the remainder of the string is
+ returned as the first element of the list (thus, the list will have at most
+ ``maxsplit+1`` elements).
+
+ .. versionadded:: 2.4
+
+
+.. function:: splitfields(s[, sep[, maxsplit]])
+
+ This function behaves identically to :func:`split`. (In the past, :func:`split`
+ was only used with one argument, while :func:`splitfields` was only used with
+ two arguments.)
+
+
+.. function:: join(words[, sep])
+
+ Concatenate a list or tuple of words with intervening occurrences of *sep*.
+ The default value for *sep* is a single space character. It is always true that
+ ``string.join(string.split(s, sep), sep)`` equals *s*.
+
+
+.. function:: joinfields(words[, sep])
+
+ This function behaves identically to :func:`join`. (In the past, :func:`join`
+ was only used with one argument, while :func:`joinfields` was only used with two
+ arguments.) Note that there is no :meth:`joinfields` method on string objects;
+ use the :meth:`join` method instead.
+
+
+.. function:: lstrip(s[, chars])
+
+ Return a copy of the string with leading characters removed. If *chars* is
+ omitted or ``None``, whitespace characters are removed. If given and not
+ ``None``, *chars* must be a string; the characters in the string will be
+ stripped from the beginning of the string this method is called on.
+
+ .. versionchanged:: 2.2.3
+ The *chars* parameter was added. The *chars* parameter cannot be passed in
+ earlier 2.2 versions.
+
+
+.. function:: rstrip(s[, chars])
+
+ Return a copy of the string with trailing characters removed. If *chars* is
+ omitted or ``None``, whitespace characters are removed. If given and not
+ ``None``, *chars* must be a string; the characters in the string will be
+ stripped from the end of the string this method is called on.
+
+ .. versionchanged:: 2.2.3
+ The *chars* parameter was added. The *chars* parameter cannot be passed in
+ earlier 2.2 versions.
+
+
+.. function:: strip(s[, chars])
+
+ Return a copy of the string with leading and trailing characters removed. If
+ *chars* is omitted or ``None``, whitespace characters are removed. If given and
+ not ``None``, *chars* must be a string; the characters in the string will be
+ stripped from the both ends of the string this method is called on.
+
+ .. versionchanged:: 2.2.3
+ The *chars* parameter was added. The *chars* parameter cannot be passed in
+ earlier 2.2 versions.
+
+
+.. function:: swapcase(s)
+
+ Return a copy of *s*, but with lower case letters converted to upper case and
+ vice versa.
+
+
+.. function:: translate(s, table[, deletechars])
+
+ Delete all characters from *s* that are in *deletechars* (if present), and then
+ translate the characters using *table*, which must be a 256-character string
+ giving the translation for each character value, indexed by its ordinal. If
+ *table* is ``None``, then only the character deletion step is performed.
+
+
+.. function:: upper(s)
+
+ Return a copy of *s*, but with lower case letters converted to upper case.
+
+
+.. function:: ljust(s, width)
+ rjust(s, width)
+ center(s, width)
+
+ These functions respectively left-justify, right-justify and center a string in
+ a field of given width. They return a string that is at least *width*
+ characters wide, created by padding the string *s* with spaces until the given
+ width on the right, left or both sides. The string is never truncated.
+
+
+.. function:: zfill(s, width)
+
+ Pad a numeric string on the left with zero digits until the given width is
+ reached. Strings starting with a sign are handled correctly.
+
+
+.. function:: replace(str, old, new[, maxreplace])
+
+ Return a copy of string *str* with all occurrences of substring *old* replaced
+ by *new*. If the optional argument *maxreplace* is given, the first
+ *maxreplace* occurrences are replaced.
+
diff --git a/Doc/library/stringio.rst b/Doc/library/stringio.rst
new file mode 100644
index 0000000000..9e2f0da8fc
--- /dev/null
+++ b/Doc/library/stringio.rst
@@ -0,0 +1,122 @@
+
+:mod:`StringIO` --- Read and write strings as files
+===================================================
+
+.. module:: StringIO
+ :synopsis: Read and write strings as if they were files.
+
+
+This module implements a file-like class, :class:`StringIO`, that reads and
+writes a string buffer (also known as *memory files*). See the description of
+file objects for operations (section :ref:`bltin-file-objects`).
+
+
+.. class:: StringIO([buffer])
+
+ When a :class:`StringIO` object is created, it can be initialized to an existing
+ string by passing the string to the constructor. If no string is given, the
+ :class:`StringIO` will start empty. In both cases, the initial file position
+ starts at zero.
+
+ The :class:`StringIO` object can accept either Unicode or 8-bit strings, but
+ mixing the two may take some care. If both are used, 8-bit strings that cannot
+ be interpreted as 7-bit ASCII (that use the 8th bit) will cause a
+ :exc:`UnicodeError` to be raised when :meth:`getvalue` is called.
+
+The following methods of :class:`StringIO` objects require special mention:
+
+
+.. method:: StringIO.getvalue()
+
+ Retrieve the entire contents of the "file" at any time before the
+ :class:`StringIO` object's :meth:`close` method is called. See the note above
+ for information about mixing Unicode and 8-bit strings; such mixing can cause
+ this method to raise :exc:`UnicodeError`.
+
+
+.. method:: StringIO.close()
+
+ Free the memory buffer.
+
+Example usage::
+
+ import StringIO
+
+ output = StringIO.StringIO()
+ output.write('First line.\n')
+ print >>output, 'Second line.'
+
+ # Retrieve file contents -- this will be
+ # 'First line.\nSecond line.\n'
+ contents = output.getvalue()
+
+ # Close object and discard memory buffer --
+ # .getvalue() will now raise an exception.
+ output.close()
+
+
+:mod:`cStringIO` --- Faster version of :mod:`StringIO`
+======================================================
+
+.. module:: cStringIO
+ :synopsis: Faster version of StringIO, but not subclassable.
+.. moduleauthor:: Jim Fulton <jim@zope.com>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The module :mod:`cStringIO` provides an interface similar to that of the
+:mod:`StringIO` module. Heavy use of :class:`StringIO.StringIO` objects can be
+made more efficient by using the function :func:`StringIO` from this module
+instead.
+
+Since this module provides a factory function which returns objects of built-in
+types, there's no way to build your own version using subclassing. Use the
+original :mod:`StringIO` module in that case.
+
+Unlike the memory files implemented by the :mod:`StringIO` module, those
+provided by this module are not able to accept Unicode strings that cannot be
+encoded as plain ASCII strings.
+
+Calling :func:`StringIO` with a Unicode string parameter populates
+the object with the buffer representation of the Unicode string, instead of
+encoding the string.
+
+Another difference from the :mod:`StringIO` module is that calling
+:func:`StringIO` with a string parameter creates a read-only object. Unlike an
+object created without a string parameter, it does not have write methods.
+These objects are not generally visible. They turn up in tracebacks as
+:class:`StringI` and :class:`StringO`.
+
+The following data objects are provided as well:
+
+
+.. data:: InputType
+
+ The type object of the objects created by calling :func:`StringIO` with a string
+ parameter.
+
+
+.. data:: OutputType
+
+ The type object of the objects returned by calling :func:`StringIO` with no
+ parameters.
+
+There is a C API to the module as well; refer to the module source for more
+information.
+
+Example usage::
+
+ import cStringIO
+
+ output = cStringIO.StringIO()
+ output.write('First line.\n')
+ print >>output, 'Second line.'
+
+ # Retrieve file contents -- this will be
+ # 'First line.\nSecond line.\n'
+ contents = output.getvalue()
+
+ # Close object and discard memory buffer --
+ # .getvalue() will now raise an exception.
+ output.close()
+
diff --git a/Doc/library/stringprep.rst b/Doc/library/stringprep.rst
new file mode 100644
index 0000000000..b0944e4373
--- /dev/null
+++ b/Doc/library/stringprep.rst
@@ -0,0 +1,142 @@
+
+:mod:`stringprep` --- Internet String Preparation
+=================================================
+
+.. module:: stringprep
+ :synopsis: String preparation, as per RFC 3453
+.. moduleauthor:: Martin v. Löwis <martin@v.loewis.de>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.3
+
+When identifying things (such as host names) in the internet, it is often
+necessary to compare such identifications for "equality". Exactly how this
+comparison is executed may depend on the application domain, e.g. whether it
+should be case-insensitive or not. It may be also necessary to restrict the
+possible identifications, to allow only identifications consisting of
+"printable" characters.
+
+:rfc:`3454` defines a procedure for "preparing" Unicode strings in internet
+protocols. Before passing strings onto the wire, they are processed with the
+preparation procedure, after which they have a certain normalized form. The RFC
+defines a set of tables, which can be combined into profiles. Each profile must
+define which tables it uses, and what other optional parts of the ``stringprep``
+procedure are part of the profile. One example of a ``stringprep`` profile is
+``nameprep``, which is used for internationalized domain names.
+
+The module :mod:`stringprep` only exposes the tables from RFC 3454. As these
+tables would be very large to represent them as dictionaries or lists, the
+module uses the Unicode character database internally. The module source code
+itself was generated using the ``mkstringprep.py`` utility.
+
+As a result, these tables are exposed as functions, not as data structures.
+There are two kinds of tables in the RFC: sets and mappings. For a set,
+:mod:`stringprep` provides the "characteristic function", i.e. a function that
+returns true if the parameter is part of the set. For mappings, it provides the
+mapping function: given the key, it returns the associated value. Below is a
+list of all functions available in the module.
+
+
+.. function:: in_table_a1(code)
+
+ Determine whether *code* is in tableA.1 (Unassigned code points in Unicode 3.2).
+
+
+.. function:: in_table_b1(code)
+
+ Determine whether *code* is in tableB.1 (Commonly mapped to nothing).
+
+
+.. function:: map_table_b2(code)
+
+ Return the mapped value for *code* according to tableB.2 (Mapping for
+ case-folding used with NFKC).
+
+
+.. function:: map_table_b3(code)
+
+ Return the mapped value for *code* according to tableB.3 (Mapping for
+ case-folding used with no normalization).
+
+
+.. function:: in_table_c11(code)
+
+ Determine whether *code* is in tableC.1.1 (ASCII space characters).
+
+
+.. function:: in_table_c12(code)
+
+ Determine whether *code* is in tableC.1.2 (Non-ASCII space characters).
+
+
+.. function:: in_table_c11_c12(code)
+
+ Determine whether *code* is in tableC.1 (Space characters, union of C.1.1 and
+ C.1.2).
+
+
+.. function:: in_table_c21(code)
+
+ Determine whether *code* is in tableC.2.1 (ASCII control characters).
+
+
+.. function:: in_table_c22(code)
+
+ Determine whether *code* is in tableC.2.2 (Non-ASCII control characters).
+
+
+.. function:: in_table_c21_c22(code)
+
+ Determine whether *code* is in tableC.2 (Control characters, union of C.2.1 and
+ C.2.2).
+
+
+.. function:: in_table_c3(code)
+
+ Determine whether *code* is in tableC.3 (Private use).
+
+
+.. function:: in_table_c4(code)
+
+ Determine whether *code* is in tableC.4 (Non-character code points).
+
+
+.. function:: in_table_c5(code)
+
+ Determine whether *code* is in tableC.5 (Surrogate codes).
+
+
+.. function:: in_table_c6(code)
+
+ Determine whether *code* is in tableC.6 (Inappropriate for plain text).
+
+
+.. function:: in_table_c7(code)
+
+ Determine whether *code* is in tableC.7 (Inappropriate for canonical
+ representation).
+
+
+.. function:: in_table_c8(code)
+
+ Determine whether *code* is in tableC.8 (Change display properties or are
+ deprecated).
+
+
+.. function:: in_table_c9(code)
+
+ Determine whether *code* is in tableC.9 (Tagging characters).
+
+
+.. function:: in_table_d1(code)
+
+ Determine whether *code* is in tableD.1 (Characters with bidirectional property
+ "R" or "AL").
+
+
+.. function:: in_table_d2(code)
+
+ Determine whether *code* is in tableD.2 (Characters with bidirectional property
+ "L").
+
diff --git a/Doc/library/strings.rst b/Doc/library/strings.rst
new file mode 100644
index 0000000000..5c8ec4bdb9
--- /dev/null
+++ b/Doc/library/strings.rst
@@ -0,0 +1,31 @@
+
+.. _stringservices:
+
+***************
+String Services
+***************
+
+The modules described in this chapter provide a wide range of string
+manipulation operations.
+
+In addition, Python's built-in string classes support the sequence type
+methods described in the :ref:`typesseq` section, and also the
+string-specific methods described in the :ref:`string-methods` section.
+To output formatted strings use template strings or the ``%`` operator
+described in the :ref:`string-formatting` section. Also, see the
+:mod:`re` module for string functions based on regular expressions.
+
+
+.. toctree::
+
+ string.rst
+ re.rst
+ struct.rst
+ difflib.rst
+ stringio.rst
+ textwrap.rst
+ codecs.rst
+ unicodedata.rst
+ stringprep.rst
+ fpformat.rst
+
diff --git a/Doc/library/struct.rst b/Doc/library/struct.rst
new file mode 100644
index 0000000000..2f27d13ca7
--- /dev/null
+++ b/Doc/library/struct.rst
@@ -0,0 +1,292 @@
+
+:mod:`struct` --- Interpret strings as packed binary data
+=========================================================
+
+.. module:: struct
+ :synopsis: Interpret strings as packed binary data.
+
+.. index::
+ pair: C; structures
+ triple: packing; binary; data
+
+This module performs conversions between Python values and C structs represented
+as Python strings. It uses :dfn:`format strings` (explained below) as compact
+descriptions of the lay-out of the C structs and the intended conversion to/from
+Python values. This can be used in handling binary data stored in files or from
+network connections, among other sources.
+
+The module defines the following exception and functions:
+
+
+.. exception:: error
+
+ Exception raised on various occasions; argument is a string describing what is
+ wrong.
+
+
+.. function:: pack(fmt, v1, v2, ...)
+
+ Return a string containing the values ``v1, v2, ...`` packed according to the
+ given format. The arguments must match the values required by the format
+ exactly.
+
+
+.. function:: pack_into(fmt, buffer, offset, v1, v2, ...)
+
+ Pack the values ``v1, v2, ...`` according to the given format, write the packed
+ bytes into the writable *buffer* starting at *offset*. Note that the offset is
+ a required argument.
+
+ .. versionadded:: 2.5
+
+
+.. function:: unpack(fmt, string)
+
+ Unpack the string (presumably packed by ``pack(fmt, ...)``) according to the
+ given format. The result is a tuple even if it contains exactly one item. The
+ string must contain exactly the amount of data required by the format
+ (``len(string)`` must equal ``calcsize(fmt)``).
+
+
+.. function:: unpack_from(fmt, buffer[,offset=0])
+
+ Unpack the *buffer* according to tthe given format. The result is a tuple even
+ if it contains exactly one item. The *buffer* must contain at least the amount
+ of data required by the format (``len(buffer[offset:])`` must be at least
+ ``calcsize(fmt)``).
+
+ .. versionadded:: 2.5
+
+
+.. function:: calcsize(fmt)
+
+ Return the size of the struct (and hence of the string) corresponding to the
+ given format.
+
+Format characters have the following meaning; the conversion between C and
+Python values should be obvious given their types:
+
++--------+-------------------------+--------------------+-------+
+| Format | C Type | Python | Notes |
++========+=========================+====================+=======+
+| ``x`` | pad byte | no value | |
++--------+-------------------------+--------------------+-------+
+| ``c`` | :ctype:`char` | string of length 1 | |
++--------+-------------------------+--------------------+-------+
+| ``b`` | :ctype:`signed char` | integer | |
++--------+-------------------------+--------------------+-------+
+| ``B`` | :ctype:`unsigned char` | integer | |
++--------+-------------------------+--------------------+-------+
+| ``t`` | :ctype:`_Bool` | bool | \(1) |
++--------+-------------------------+--------------------+-------+
+| ``h`` | :ctype:`short` | integer | |
++--------+-------------------------+--------------------+-------+
+| ``H`` | :ctype:`unsigned short` | integer | |
++--------+-------------------------+--------------------+-------+
+| ``i`` | :ctype:`int` | integer | |
++--------+-------------------------+--------------------+-------+
+| ``I`` | :ctype:`unsigned int` | long | |
++--------+-------------------------+--------------------+-------+
+| ``l`` | :ctype:`long` | integer | |
++--------+-------------------------+--------------------+-------+
+| ``L`` | :ctype:`unsigned long` | long | |
++--------+-------------------------+--------------------+-------+
+| ``q`` | :ctype:`long long` | long | \(2) |
++--------+-------------------------+--------------------+-------+
+| ``Q`` | :ctype:`unsigned long | long | \(2) |
+| | long` | | |
++--------+-------------------------+--------------------+-------+
+| ``f`` | :ctype:`float` | float | |
++--------+-------------------------+--------------------+-------+
+| ``d`` | :ctype:`double` | float | |
++--------+-------------------------+--------------------+-------+
+| ``s`` | :ctype:`char[]` | string | |
++--------+-------------------------+--------------------+-------+
+| ``p`` | :ctype:`char[]` | string | |
++--------+-------------------------+--------------------+-------+
+| ``P`` | :ctype:`void \*` | integer | |
++--------+-------------------------+--------------------+-------+
+
+Notes:
+
+(1)
+ The ``'t'`` conversion code corresponds to the :ctype:`_Bool` type defined by
+ C99. If this type is not available, it is simulated using a :ctype:`char`. In
+ standard mode, it is always represented by one byte.
+
+ .. versionadded:: 2.6
+
+(2)
+ The ``'q'`` and ``'Q'`` conversion codes are available in native mode only if
+ the platform C compiler supports C :ctype:`long long`, or, on Windows,
+ :ctype:`__int64`. They are always available in standard modes.
+
+ .. versionadded:: 2.2
+
+A format character may be preceded by an integral repeat count. For example,
+the format string ``'4h'`` means exactly the same as ``'hhhh'``.
+
+Whitespace characters between formats are ignored; a count and its format must
+not contain whitespace though.
+
+For the ``'s'`` format character, the count is interpreted as the size of the
+string, not a repeat count like for the other format characters; for example,
+``'10s'`` means a single 10-byte string, while ``'10c'`` means 10 characters.
+For packing, the string is truncated or padded with null bytes as appropriate to
+make it fit. For unpacking, the resulting string always has exactly the
+specified number of bytes. As a special case, ``'0s'`` means a single, empty
+string (while ``'0c'`` means 0 characters).
+
+The ``'p'`` format character encodes a "Pascal string", meaning a short
+variable-length string stored in a fixed number of bytes. The count is the total
+number of bytes stored. The first byte stored is the length of the string, or
+255, whichever is smaller. The bytes of the string follow. If the string
+passed in to :func:`pack` is too long (longer than the count minus 1), only the
+leading count-1 bytes of the string are stored. If the string is shorter than
+count-1, it is padded with null bytes so that exactly count bytes in all are
+used. Note that for :func:`unpack`, the ``'p'`` format character consumes count
+bytes, but that the string returned can never contain more than 255 characters.
+
+For the ``'I'``, ``'L'``, ``'q'`` and ``'Q'`` format characters, the return
+value is a Python long integer.
+
+For the ``'P'`` format character, the return value is a Python integer or long
+integer, depending on the size needed to hold a pointer when it has been cast to
+an integer type. A *NULL* pointer will always be returned as the Python integer
+``0``. When packing pointer-sized values, Python integer or long integer objects
+may be used. For example, the Alpha and Merced processors use 64-bit pointer
+values, meaning a Python long integer will be used to hold the pointer; other
+platforms use 32-bit pointers and will use a Python integer.
+
+For the ``'t'`` format character, the return value is either :const:`True` or
+:const:`False`. When packing, the truth value of the argument object is used.
+Either 0 or 1 in the native or standard bool representation will be packed, and
+any non-zero value will be True when unpacking.
+
+By default, C numbers are represented in the machine's native format and byte
+order, and properly aligned by skipping pad bytes if necessary (according to the
+rules used by the C compiler).
+
+Alternatively, the first character of the format string can be used to indicate
+the byte order, size and alignment of the packed data, according to the
+following table:
+
++-----------+------------------------+--------------------+
+| Character | Byte order | Size and alignment |
++===========+========================+====================+
+| ``@`` | native | native |
++-----------+------------------------+--------------------+
+| ``=`` | native | standard |
++-----------+------------------------+--------------------+
+| ``<`` | little-endian | standard |
++-----------+------------------------+--------------------+
+| ``>`` | big-endian | standard |
++-----------+------------------------+--------------------+
+| ``!`` | network (= big-endian) | standard |
++-----------+------------------------+--------------------+
+
+If the first character is not one of these, ``'@'`` is assumed.
+
+Native byte order is big-endian or little-endian, depending on the host system.
+For example, Motorola and Sun processors are big-endian; Intel and DEC
+processors are little-endian.
+
+Native size and alignment are determined using the C compiler's
+:keyword:`sizeof` expression. This is always combined with native byte order.
+
+Standard size and alignment are as follows: no alignment is required for any
+type (so you have to use pad bytes); :ctype:`short` is 2 bytes; :ctype:`int` and
+:ctype:`long` are 4 bytes; :ctype:`long long` (:ctype:`__int64` on Windows) is 8
+bytes; :ctype:`float` and :ctype:`double` are 32-bit and 64-bit IEEE floating
+point numbers, respectively. :ctype:`_Bool` is 1 byte.
+
+Note the difference between ``'@'`` and ``'='``: both use native byte order, but
+the size and alignment of the latter is standardized.
+
+The form ``'!'`` is available for those poor souls who claim they can't remember
+whether network byte order is big-endian or little-endian.
+
+There is no way to indicate non-native byte order (force byte-swapping); use the
+appropriate choice of ``'<'`` or ``'>'``.
+
+The ``'P'`` format character is only available for the native byte ordering
+(selected as the default or with the ``'@'`` byte order character). The byte
+order character ``'='`` chooses to use little- or big-endian ordering based on
+the host system. The struct module does not interpret this as native ordering,
+so the ``'P'`` format is not available.
+
+Examples (all using native byte order, size and alignment, on a big-endian
+machine)::
+
+ >>> from struct import *
+ >>> pack('hhl', 1, 2, 3)
+ '\x00\x01\x00\x02\x00\x00\x00\x03'
+ >>> unpack('hhl', '\x00\x01\x00\x02\x00\x00\x00\x03')
+ (1, 2, 3)
+ >>> calcsize('hhl')
+ 8
+
+Hint: to align the end of a structure to the alignment requirement of a
+particular type, end the format with the code for that type with a repeat count
+of zero. For example, the format ``'llh0l'`` specifies two pad bytes at the
+end, assuming longs are aligned on 4-byte boundaries. This only works when
+native size and alignment are in effect; standard size and alignment does not
+enforce any alignment.
+
+
+.. seealso::
+
+ Module :mod:`array`
+ Packed binary storage of homogeneous data.
+
+ Module :mod:`xdrlib`
+ Packing and unpacking of XDR data.
+
+
+.. _struct-objects:
+
+Struct Objects
+--------------
+
+The :mod:`struct` module also defines the following type:
+
+
+.. class:: Struct(format)
+
+ Return a new Struct object which writes and reads binary data according to the
+ format string *format*. Creating a Struct object once and calling its methods
+ is more efficient than calling the :mod:`struct` functions with the same format
+ since the format string only needs to be compiled once.
+
+ .. versionadded:: 2.5
+
+Compiled Struct objects support the following methods and attributes:
+
+
+.. method:: Struct.pack(v1, v2, ...)
+
+ Identical to the :func:`pack` function, using the compiled format.
+ (``len(result)`` will equal :attr:`self.size`.)
+
+
+.. method:: Struct.pack_into(buffer, offset, v1, v2, ...)
+
+ Identical to the :func:`pack_into` function, using the compiled format.
+
+
+.. method:: Struct.unpack(string)
+
+ Identical to the :func:`unpack` function, using the compiled format.
+ (``len(string)`` must equal :attr:`self.size`).
+
+
+.. method:: Struct.unpack_from(buffer[, offset=0])
+
+ Identical to the :func:`unpack_from` function, using the compiled format.
+ (``len(buffer[offset:])`` must be at least :attr:`self.size`).
+
+
+.. attribute:: Struct.format
+
+ The format string used to construct this Struct object.
+
diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst
new file mode 100644
index 0000000000..a3bc2cb3ea
--- /dev/null
+++ b/Doc/library/subprocess.rst
@@ -0,0 +1,340 @@
+
+:mod:`subprocess` --- Subprocess management
+===========================================
+
+.. module:: subprocess
+ :synopsis: Subprocess management.
+.. moduleauthor:: Peter Åstrand <astrand@lysator.liu.se>
+.. sectionauthor:: Peter Åstrand <astrand@lysator.liu.se>
+
+
+.. versionadded:: 2.4
+
+The :mod:`subprocess` module allows you to spawn new processes, connect to their
+input/output/error pipes, and obtain their return codes. This module intends to
+replace several other, older modules and functions, such as::
+
+ os.system
+ os.spawn*
+ commands.*
+
+Information about how the :mod:`subprocess` module can be used to replace these
+modules and functions can be found in the following sections.
+
+
+Using the subprocess Module
+---------------------------
+
+This module defines one class called :class:`Popen`:
+
+
+.. class:: Popen(args, bufsize=0, executable=None, stdin=None, stdout=None, stderr=None, preexec_fn=None, close_fds=False, shell=False, cwd=None, env=None, universal_newlines=False, startupinfo=None, creationflags=0)
+
+ Arguments are:
+
+ *args* should be a string, or a sequence of program arguments. The program to
+ execute is normally the first item in the args sequence or string, but can be
+ explicitly set by using the executable argument.
+
+ On Unix, with *shell=False* (default): In this case, the Popen class uses
+ :meth:`os.execvp` to execute the child program. *args* should normally be a
+ sequence. A string will be treated as a sequence with the string as the only
+ item (the program to execute).
+
+ On Unix, with *shell=True*: If args is a string, it specifies the command string
+ to execute through the shell. If *args* is a sequence, the first item specifies
+ the command string, and any additional items will be treated as additional shell
+ arguments.
+
+ On Windows: the :class:`Popen` class uses CreateProcess() to execute the child
+ program, which operates on strings. If *args* is a sequence, it will be
+ converted to a string using the :meth:`list2cmdline` method. Please note that
+ not all MS Windows applications interpret the command line the same way:
+ :meth:`list2cmdline` is designed for applications using the same rules as the MS
+ C runtime.
+
+ *bufsize*, if given, has the same meaning as the corresponding argument to the
+ built-in open() function: :const:`0` means unbuffered, :const:`1` means line
+ buffered, any other positive value means use a buffer of (approximately) that
+ size. A negative *bufsize* means to use the system default, which usually means
+ fully buffered. The default value for *bufsize* is :const:`0` (unbuffered).
+
+ The *executable* argument specifies the program to execute. It is very seldom
+ needed: Usually, the program to execute is defined by the *args* argument. If
+ ``shell=True``, the *executable* argument specifies which shell to use. On Unix,
+ the default shell is :file:`/bin/sh`. On Windows, the default shell is
+ specified by the :envvar:`COMSPEC` environment variable.
+
+ *stdin*, *stdout* and *stderr* specify the executed programs' standard input,
+ standard output and standard error file handles, respectively. Valid values are
+ ``PIPE``, an existing file descriptor (a positive integer), an existing file
+ object, and ``None``. ``PIPE`` indicates that a new pipe to the child should be
+ created. With ``None``, no redirection will occur; the child's file handles
+ will be inherited from the parent. Additionally, *stderr* can be ``STDOUT``,
+ which indicates that the stderr data from the applications should be captured
+ into the same file handle as for stdout.
+
+ If *preexec_fn* is set to a callable object, this object will be called in the
+ child process just before the child is executed. (Unix only)
+
+ If *close_fds* is true, all file descriptors except :const:`0`, :const:`1` and
+ :const:`2` will be closed before the child process is executed. (Unix only).
+ Or, on Windows, if *close_fds* is true then no handles will be inherited by the
+ child process. Note that on Windows, you cannot set *close_fds* to true and
+ also redirect the standard handles by setting *stdin*, *stdout* or *stderr*.
+
+ If *shell* is :const:`True`, the specified command will be executed through the
+ shell.
+
+ If *cwd* is not ``None``, the child's current directory will be changed to *cwd*
+ before it is executed. Note that this directory is not considered when
+ searching the executable, so you can't specify the program's path relative to
+ *cwd*.
+
+ If *env* is not ``None``, it defines the environment variables for the new
+ process.
+
+ If *universal_newlines* is :const:`True`, the file objects stdout and stderr are
+ opened as text files, but lines may be terminated by any of ``'\n'``, the Unix
+ end-of-line convention, ``'\r'``, the Macintosh convention or ``'\r\n'``, the
+ Windows convention. All of these external representations are seen as ``'\n'``
+ by the Python program.
+
+ .. note::
+
+ This feature is only available if Python is built with universal newline support
+ (the default). Also, the newlines attribute of the file objects :attr:`stdout`,
+ :attr:`stdin` and :attr:`stderr` are not updated by the communicate() method.
+
+ The *startupinfo* and *creationflags*, if given, will be passed to the
+ underlying CreateProcess() function. They can specify things such as appearance
+ of the main window and priority for the new process. (Windows only)
+
+
+Convenience Functions
+^^^^^^^^^^^^^^^^^^^^^
+
+This module also defines two shortcut functions:
+
+
+.. function:: call(*popenargs, **kwargs)
+
+ Run command with arguments. Wait for command to complete, then return the
+ :attr:`returncode` attribute.
+
+ The arguments are the same as for the Popen constructor. Example::
+
+ retcode = call(["ls", "-l"])
+
+
+.. function:: check_call(*popenargs, **kwargs)
+
+ Run command with arguments. Wait for command to complete. If the exit code was
+ zero then return, otherwise raise :exc:`CalledProcessError.` The
+ :exc:`CalledProcessError` object will have the return code in the
+ :attr:`returncode` attribute.
+
+ The arguments are the same as for the Popen constructor. Example::
+
+ check_call(["ls", "-l"])
+
+ .. versionadded:: 2.5
+
+
+Exceptions
+^^^^^^^^^^
+
+Exceptions raised in the child process, before the new program has started to
+execute, will be re-raised in the parent. Additionally, the exception object
+will have one extra attribute called :attr:`child_traceback`, which is a string
+containing traceback information from the childs point of view.
+
+The most common exception raised is :exc:`OSError`. This occurs, for example,
+when trying to execute a non-existent file. Applications should prepare for
+:exc:`OSError` exceptions.
+
+A :exc:`ValueError` will be raised if :class:`Popen` is called with invalid
+arguments.
+
+check_call() will raise :exc:`CalledProcessError`, if the called process returns
+a non-zero return code.
+
+
+Security
+^^^^^^^^
+
+Unlike some other popen functions, this implementation will never call /bin/sh
+implicitly. This means that all characters, including shell metacharacters, can
+safely be passed to child processes.
+
+
+Popen Objects
+-------------
+
+Instances of the :class:`Popen` class have the following methods:
+
+
+.. method:: Popen.poll()
+
+ Check if child process has terminated. Returns returncode attribute.
+
+
+.. method:: Popen.wait()
+
+ Wait for child process to terminate. Returns returncode attribute.
+
+
+.. method:: Popen.communicate(input=None)
+
+ Interact with process: Send data to stdin. Read data from stdout and stderr,
+ until end-of-file is reached. Wait for process to terminate. The optional
+ *input* argument should be a string to be sent to the child process, or
+ ``None``, if no data should be sent to the child.
+
+ communicate() returns a tuple (stdout, stderr).
+
+ .. note::
+
+ The data read is buffered in memory, so do not use this method if the data size
+ is large or unlimited.
+
+The following attributes are also available:
+
+
+.. attribute:: Popen.stdin
+
+ If the *stdin* argument is ``PIPE``, this attribute is a file object that
+ provides input to the child process. Otherwise, it is ``None``.
+
+
+.. attribute:: Popen.stdout
+
+ If the *stdout* argument is ``PIPE``, this attribute is a file object that
+ provides output from the child process. Otherwise, it is ``None``.
+
+
+.. attribute:: Popen.stderr
+
+ If the *stderr* argument is ``PIPE``, this attribute is file object that
+ provides error output from the child process. Otherwise, it is ``None``.
+
+
+.. attribute:: Popen.pid
+
+ The process ID of the child process.
+
+
+.. attribute:: Popen.returncode
+
+ The child return code. A ``None`` value indicates that the process hasn't
+ terminated yet. A negative value -N indicates that the child was terminated by
+ signal N (Unix only).
+
+
+Replacing Older Functions with the subprocess Module
+----------------------------------------------------
+
+In this section, "a ==> b" means that b can be used as a replacement for a.
+
+.. note::
+
+ All functions in this section fail (more or less) silently if the executed
+ program cannot be found; this module raises an :exc:`OSError` exception.
+
+In the following examples, we assume that the subprocess module is imported with
+"from subprocess import \*".
+
+
+Replacing /bin/sh shell backquote
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+::
+
+ output=`mycmd myarg`
+ ==>
+ output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0]
+
+
+Replacing shell pipe line
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+::
+
+ output=`dmesg | grep hda`
+ ==>
+ p1 = Popen(["dmesg"], stdout=PIPE)
+ p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
+ output = p2.communicate()[0]
+
+
+Replacing os.system()
+^^^^^^^^^^^^^^^^^^^^^
+
+::
+
+ sts = os.system("mycmd" + " myarg")
+ ==>
+ p = Popen("mycmd" + " myarg", shell=True)
+ sts = os.waitpid(p.pid, 0)
+
+Notes:
+
+* Calling the program through the shell is usually not required.
+
+* It's easier to look at the :attr:`returncode` attribute than the exit status.
+
+A more realistic example would look like this::
+
+ try:
+ retcode = call("mycmd" + " myarg", shell=True)
+ if retcode < 0:
+ print >>sys.stderr, "Child was terminated by signal", -retcode
+ else:
+ print >>sys.stderr, "Child returned", retcode
+ except OSError as e:
+ print >>sys.stderr, "Execution failed:", e
+
+
+Replacing os.spawn\*
+^^^^^^^^^^^^^^^^^^^^
+
+P_NOWAIT example::
+
+ pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg")
+ ==>
+ pid = Popen(["/bin/mycmd", "myarg"]).pid
+
+P_WAIT example::
+
+ retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg")
+ ==>
+ retcode = call(["/bin/mycmd", "myarg"])
+
+Vector example::
+
+ os.spawnvp(os.P_NOWAIT, path, args)
+ ==>
+ Popen([path] + args[1:])
+
+Environment example::
+
+ os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env)
+ ==>
+ Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"})
+
+
+Replacing os.popen\*
+^^^^^^^^^^^^^^^^^^^^
+
+::
+
+ pipe = os.popen(cmd, mode='r', bufsize)
+ ==>
+ pipe = Popen(cmd, shell=True, bufsize=bufsize, stdout=PIPE).stdout
+
+::
+
+ pipe = os.popen(cmd, mode='w', bufsize)
+ ==>
+ pipe = Popen(cmd, shell=True, bufsize=bufsize, stdin=PIPE).stdin
+
diff --git a/Doc/library/sunau.rst b/Doc/library/sunau.rst
new file mode 100644
index 0000000000..9930133f2c
--- /dev/null
+++ b/Doc/library/sunau.rst
@@ -0,0 +1,261 @@
+
+:mod:`sunau` --- Read and write Sun AU files
+============================================
+
+.. module:: sunau
+ :synopsis: Provide an interface to the Sun AU sound format.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`sunau` module provides a convenient interface to the Sun AU sound
+format. Note that this module is interface-compatible with the modules
+:mod:`aifc` and :mod:`wave`.
+
+An audio file consists of a header followed by the data. The fields of the
+header are:
+
++---------------+-----------------------------------------------+
+| Field | Contents |
++===============+===============================================+
+| magic word | The four bytes ``.snd``. |
++---------------+-----------------------------------------------+
+| header size | Size of the header, including info, in bytes. |
++---------------+-----------------------------------------------+
+| data size | Physical size of the data, in bytes. |
++---------------+-----------------------------------------------+
+| encoding | Indicates how the audio samples are encoded. |
++---------------+-----------------------------------------------+
+| sample rate | The sampling rate. |
++---------------+-----------------------------------------------+
+| # of channels | The number of channels in the samples. |
++---------------+-----------------------------------------------+
+| info | ASCII string giving a description of the |
+| | audio file (padded with null bytes). |
++---------------+-----------------------------------------------+
+
+Apart from the info field, all header fields are 4 bytes in size. They are all
+32-bit unsigned integers encoded in big-endian byte order.
+
+The :mod:`sunau` module defines the following functions:
+
+
+.. function:: open(file, mode)
+
+ If *file* is a string, open the file by that name, otherwise treat it as a
+ seekable file-like object. *mode* can be any of
+
+ ``'r'``
+ Read only mode.
+
+ ``'w'``
+ Write only mode.
+
+ Note that it does not allow read/write files.
+
+ A *mode* of ``'r'`` returns a :class:`AU_read` object, while a *mode* of ``'w'``
+ or ``'wb'`` returns a :class:`AU_write` object.
+
+
+.. function:: openfp(file, mode)
+
+ A synonym for :func:`open`, maintained for backwards compatibility.
+
+The :mod:`sunau` module defines the following exception:
+
+
+.. exception:: Error
+
+ An error raised when something is impossible because of Sun AU specs or
+ implementation deficiency.
+
+The :mod:`sunau` module defines the following data items:
+
+
+.. data:: AUDIO_FILE_MAGIC
+
+ An integer every valid Sun AU file begins with, stored in big-endian form. This
+ is the string ``.snd`` interpreted as an integer.
+
+
+.. data:: AUDIO_FILE_ENCODING_MULAW_8
+ AUDIO_FILE_ENCODING_LINEAR_8
+ AUDIO_FILE_ENCODING_LINEAR_16
+ AUDIO_FILE_ENCODING_LINEAR_24
+ AUDIO_FILE_ENCODING_LINEAR_32
+ AUDIO_FILE_ENCODING_ALAW_8
+
+ Values of the encoding field from the AU header which are supported by this
+ module.
+
+
+.. data:: AUDIO_FILE_ENCODING_FLOAT
+ AUDIO_FILE_ENCODING_DOUBLE
+ AUDIO_FILE_ENCODING_ADPCM_G721
+ AUDIO_FILE_ENCODING_ADPCM_G722
+ AUDIO_FILE_ENCODING_ADPCM_G723_3
+ AUDIO_FILE_ENCODING_ADPCM_G723_5
+
+ Additional known values of the encoding field from the AU header, but which are
+ not supported by this module.
+
+
+.. _au-read-objects:
+
+AU_read Objects
+---------------
+
+AU_read objects, as returned by :func:`open` above, have the following methods:
+
+
+.. method:: AU_read.close()
+
+ Close the stream, and make the instance unusable. (This is called automatically
+ on deletion.)
+
+
+.. method:: AU_read.getnchannels()
+
+ Returns number of audio channels (1 for mone, 2 for stereo).
+
+
+.. method:: AU_read.getsampwidth()
+
+ Returns sample width in bytes.
+
+
+.. method:: AU_read.getframerate()
+
+ Returns sampling frequency.
+
+
+.. method:: AU_read.getnframes()
+
+ Returns number of audio frames.
+
+
+.. method:: AU_read.getcomptype()
+
+ Returns compression type. Supported compression types are ``'ULAW'``, ``'ALAW'``
+ and ``'NONE'``.
+
+
+.. method:: AU_read.getcompname()
+
+ Human-readable version of :meth:`getcomptype`. The supported types have the
+ respective names ``'CCITT G.711 u-law'``, ``'CCITT G.711 A-law'`` and ``'not
+ compressed'``.
+
+
+.. method:: AU_read.getparams()
+
+ Returns a tuple ``(nchannels, sampwidth, framerate, nframes, comptype,
+ compname)``, equivalent to output of the :meth:`get\*` methods.
+
+
+.. method:: AU_read.readframes(n)
+
+ Reads and returns at most *n* frames of audio, as a string of bytes. The data
+ will be returned in linear format. If the original data is in u-LAW format, it
+ will be converted.
+
+
+.. method:: AU_read.rewind()
+
+ Rewind the file pointer to the beginning of the audio stream.
+
+The following two methods define a term "position" which is compatible between
+them, and is otherwise implementation dependent.
+
+
+.. method:: AU_read.setpos(pos)
+
+ Set the file pointer to the specified position. Only values returned from
+ :meth:`tell` should be used for *pos*.
+
+
+.. method:: AU_read.tell()
+
+ Return current file pointer position. Note that the returned value has nothing
+ to do with the actual position in the file.
+
+The following two functions are defined for compatibility with the :mod:`aifc`,
+and don't do anything interesting.
+
+
+.. method:: AU_read.getmarkers()
+
+ Returns ``None``.
+
+
+.. method:: AU_read.getmark(id)
+
+ Raise an error.
+
+
+.. _au-write-objects:
+
+AU_write Objects
+----------------
+
+AU_write objects, as returned by :func:`open` above, have the following methods:
+
+
+.. method:: AU_write.setnchannels(n)
+
+ Set the number of channels.
+
+
+.. method:: AU_write.setsampwidth(n)
+
+ Set the sample width (in bytes.)
+
+
+.. method:: AU_write.setframerate(n)
+
+ Set the frame rate.
+
+
+.. method:: AU_write.setnframes(n)
+
+ Set the number of frames. This can be later changed, when and if more frames
+ are written.
+
+
+.. method:: AU_write.setcomptype(type, name)
+
+ Set the compression type and description. Only ``'NONE'`` and ``'ULAW'`` are
+ supported on output.
+
+
+.. method:: AU_write.setparams(tuple)
+
+ The *tuple* should be ``(nchannels, sampwidth, framerate, nframes, comptype,
+ compname)``, with values valid for the :meth:`set\*` methods. Set all
+ parameters.
+
+
+.. method:: AU_write.tell()
+
+ Return current position in the file, with the same disclaimer for the
+ :meth:`AU_read.tell` and :meth:`AU_read.setpos` methods.
+
+
+.. method:: AU_write.writeframesraw(data)
+
+ Write audio frames, without correcting *nframes*.
+
+
+.. method:: AU_write.writeframes(data)
+
+ Write audio frames and make sure *nframes* is correct.
+
+
+.. method:: AU_write.close()
+
+ Make sure *nframes* is correct, and close the file.
+
+ This method is called upon deletion.
+
+Note that it is invalid to set any parameters after calling :meth:`writeframes`
+or :meth:`writeframesraw`.
+
diff --git a/Doc/library/symbol.rst b/Doc/library/symbol.rst
new file mode 100644
index 0000000000..1735276fbe
--- /dev/null
+++ b/Doc/library/symbol.rst
@@ -0,0 +1,32 @@
+
+:mod:`symbol` --- Constants used with Python parse trees
+========================================================
+
+.. module:: symbol
+ :synopsis: Constants representing internal nodes of the parse tree.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+This module provides constants which represent the numeric values of internal
+nodes of the parse tree. Unlike most Python constants, these use lower-case
+names. Refer to the file :file:`Grammar/Grammar` in the Python distribution for
+the definitions of the names in the context of the language grammar. The
+specific numeric values which the names map to may change between Python
+versions.
+
+This module also provides one additional data object:
+
+
+.. data:: sym_name
+
+ Dictionary mapping the numeric values of the constants defined in this module
+ back to name strings, allowing more human-readable representation of parse trees
+ to be generated.
+
+
+.. seealso::
+
+ Module :mod:`parser`
+ The second example for the :mod:`parser` module shows how to use the
+ :mod:`symbol` module.
+
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
new file mode 100644
index 0000000000..5184c25756
--- /dev/null
+++ b/Doc/library/sys.rst
@@ -0,0 +1,606 @@
+
+:mod:`sys` --- System-specific parameters and functions
+=======================================================
+
+.. module:: sys
+ :synopsis: Access system-specific parameters and functions.
+
+
+This module provides access to some variables used or maintained by the
+interpreter and to functions that interact strongly with the interpreter. It is
+always available.
+
+
+.. data:: argv
+
+ The list of command line arguments passed to a Python script. ``argv[0]`` is the
+ script name (it is operating system dependent whether this is a full pathname or
+ not). If the command was executed using the :option:`-c` command line option to
+ the interpreter, ``argv[0]`` is set to the string ``'-c'``. If no script name
+ was passed to the Python interpreter, ``argv[0]`` is the empty string.
+
+ To loop over the standard input, or the list of files given on the
+ command line, see the :mod:`fileinput` module.
+
+
+.. data:: byteorder
+
+ An indicator of the native byte order. This will have the value ``'big'`` on
+ big-endian (most-significant byte first) platforms, and ``'little'`` on
+ little-endian (least-significant byte first) platforms.
+
+ .. versionadded:: 2.0
+
+
+.. data:: subversion
+
+ A triple (repo, branch, version) representing the Subversion information of the
+ Python interpreter. *repo* is the name of the repository, ``'CPython'``.
+ *branch* is a string of one of the forms ``'trunk'``, ``'branches/name'`` or
+ ``'tags/name'``. *version* is the output of ``svnversion``, if the interpreter
+ was built from a Subversion checkout; it contains the revision number (range)
+ and possibly a trailing 'M' if there were local modifications. If the tree was
+ exported (or svnversion was not available), it is the revision of
+ ``Include/patchlevel.h`` if the branch is a tag. Otherwise, it is ``None``.
+
+ .. versionadded:: 2.5
+
+
+.. data:: builtin_module_names
+
+ A tuple of strings giving the names of all modules that are compiled into this
+ Python interpreter. (This information is not available in any other way ---
+ ``modules.keys()`` only lists the imported modules.)
+
+
+.. data:: copyright
+
+ A string containing the copyright pertaining to the Python interpreter.
+
+
+.. function:: _current_frames()
+
+ Return a dictionary mapping each thread's identifier to the topmost stack frame
+ currently active in that thread at the time the function is called. Note that
+ functions in the :mod:`traceback` module can build the call stack given such a
+ frame.
+
+ This is most useful for debugging deadlock: this function does not require the
+ deadlocked threads' cooperation, and such threads' call stacks are frozen for as
+ long as they remain deadlocked. The frame returned for a non-deadlocked thread
+ may bear no relationship to that thread's current activity by the time calling
+ code examines the frame.
+
+ This function should be used for internal and specialized purposes only.
+
+ .. versionadded:: 2.5
+
+
+.. data:: dllhandle
+
+ Integer specifying the handle of the Python DLL. Availability: Windows.
+
+
+.. function:: displayhook(value)
+
+ If *value* is not ``None``, this function prints it to ``sys.stdout``, and saves
+ it in ``__builtin__._``.
+
+ ``sys.displayhook`` is called on the result of evaluating an expression entered
+ in an interactive Python session. The display of these values can be customized
+ by assigning another one-argument function to ``sys.displayhook``.
+
+
+.. function:: excepthook(type, value, traceback)
+
+ This function prints out a given traceback and exception to ``sys.stderr``.
+
+ When an exception is raised and uncaught, the interpreter calls
+ ``sys.excepthook`` with three arguments, the exception class, exception
+ instance, and a traceback object. In an interactive session this happens just
+ before control is returned to the prompt; in a Python program this happens just
+ before the program exits. The handling of such top-level exceptions can be
+ customized by assigning another three-argument function to ``sys.excepthook``.
+
+
+.. data:: __displayhook__
+ __excepthook__
+
+ These objects contain the original values of ``displayhook`` and ``excepthook``
+ at the start of the program. They are saved so that ``displayhook`` and
+ ``excepthook`` can be restored in case they happen to get replaced with broken
+ objects.
+
+
+.. function:: exc_info()
+
+ This function returns a tuple of three values that give information about the
+ exception that is currently being handled. The information returned is specific
+ both to the current thread and to the current stack frame. If the current stack
+ frame is not handling an exception, the information is taken from the calling
+ stack frame, or its caller, and so on until a stack frame is found that is
+ handling an exception. Here, "handling an exception" is defined as "executing
+ or having executed an except clause." For any stack frame, only information
+ about the most recently handled exception is accessible.
+
+ .. index:: object: traceback
+
+ If no exception is being handled anywhere on the stack, a tuple containing three
+ ``None`` values is returned. Otherwise, the values returned are ``(type, value,
+ traceback)``. Their meaning is: *type* gets the exception type of the exception
+ being handled (a class object); *value* gets the exception parameter (its
+ :dfn:`associated value` or the second argument to :keyword:`raise`, which is
+ always a class instance if the exception type is a class object); *traceback*
+ gets a traceback object (see the Reference Manual) which encapsulates the call
+ stack at the point where the exception originally occurred.
+
+ .. warning::
+
+ Assigning the *traceback* return value to a local variable in a function that is
+ handling an exception will cause a circular reference. This will prevent
+ anything referenced by a local variable in the same function or by the traceback
+ from being garbage collected. Since most functions don't need access to the
+ traceback, the best solution is to use something like ``exctype, value =
+ sys.exc_info()[:2]`` to extract only the exception type and value. If you do
+ need the traceback, make sure to delete it after use (best done with a
+ :keyword:`try` ... :keyword:`finally` statement) or to call :func:`exc_info` in
+ a function that does not itself handle an exception.
+
+ .. note::
+
+ Beginning with Python 2.2, such cycles are automatically reclaimed when garbage
+ collection is enabled and they become unreachable, but it remains more efficient
+ to avoid creating cycles.
+
+
+.. data:: exec_prefix
+
+ A string giving the site-specific directory prefix where the platform-dependent
+ Python files are installed; by default, this is also ``'/usr/local'``. This can
+ be set at build time with the :option:`--exec-prefix` argument to the
+ :program:`configure` script. Specifically, all configuration files (e.g. the
+ :file:`pyconfig.h` header file) are installed in the directory ``exec_prefix +
+ '/lib/pythonversion/config'``, and shared library modules are installed in
+ ``exec_prefix + '/lib/pythonversion/lib-dynload'``, where *version* is equal to
+ ``version[:3]``.
+
+
+.. data:: executable
+
+ A string giving the name of the executable binary for the Python interpreter, on
+ systems where this makes sense.
+
+
+.. function:: exit([arg])
+
+ Exit from Python. This is implemented by raising the :exc:`SystemExit`
+ exception, so cleanup actions specified by finally clauses of :keyword:`try`
+ statements are honored, and it is possible to intercept the exit attempt at an
+ outer level. The optional argument *arg* can be an integer giving the exit
+ status (defaulting to zero), or another type of object. If it is an integer,
+ zero is considered "successful termination" and any nonzero value is considered
+ "abnormal termination" by shells and the like. Most systems require it to be in
+ the range 0-127, and produce undefined results otherwise. Some systems have a
+ convention for assigning specific meanings to specific exit codes, but these are
+ generally underdeveloped; Unix programs generally use 2 for command line syntax
+ errors and 1 for all other kind of errors. If another type of object is passed,
+ ``None`` is equivalent to passing zero, and any other object is printed to
+ ``sys.stderr`` and results in an exit code of 1. In particular,
+ ``sys.exit("some error message")`` is a quick way to exit a program when an
+ error occurs.
+
+
+.. function:: getcheckinterval()
+
+ Return the interpreter's "check interval"; see :func:`setcheckinterval`.
+
+ .. versionadded:: 2.3
+
+
+.. function:: getdefaultencoding()
+
+ Return the name of the current default string encoding used by the Unicode
+ implementation.
+
+ .. versionadded:: 2.0
+
+
+.. function:: getdlopenflags()
+
+ Return the current value of the flags that are used for :cfunc:`dlopen` calls.
+ The flag constants are defined in the :mod:`dl` and :mod:`DLFCN` modules.
+ Availability: Unix.
+
+ .. versionadded:: 2.2
+
+
+.. function:: getfilesystemencoding()
+
+ Return the name of the encoding used to convert Unicode filenames into system
+ file names, or ``None`` if the system default encoding is used. The result value
+ depends on the operating system:
+
+ * On Windows 9x, the encoding is "mbcs".
+
+ * On Mac OS X, the encoding is "utf-8".
+
+ * On Unix, the encoding is the user's preference according to the result of
+ nl_langinfo(CODESET), or :const:`None` if the ``nl_langinfo(CODESET)`` failed.
+
+ * On Windows NT+, file names are Unicode natively, so no conversion is
+ performed. :func:`getfilesystemencoding` still returns ``'mbcs'``, as this is
+ the encoding that applications should use when they explicitly want to convert
+ Unicode strings to byte strings that are equivalent when used as file names.
+
+ .. versionadded:: 2.3
+
+
+.. function:: getrefcount(object)
+
+ Return the reference count of the *object*. The count returned is generally one
+ higher than you might expect, because it includes the (temporary) reference as
+ an argument to :func:`getrefcount`.
+
+
+.. function:: getrecursionlimit()
+
+ Return the current value of the recursion limit, the maximum depth of the Python
+ interpreter stack. This limit prevents infinite recursion from causing an
+ overflow of the C stack and crashing Python. It can be set by
+ :func:`setrecursionlimit`.
+
+
+.. function:: _getframe([depth])
+
+ Return a frame object from the call stack. If optional integer *depth* is
+ given, return the frame object that many calls below the top of the stack. If
+ that is deeper than the call stack, :exc:`ValueError` is raised. The default
+ for *depth* is zero, returning the frame at the top of the call stack.
+
+ This function should be used for internal and specialized purposes only.
+
+
+.. function:: getwindowsversion()
+
+ Return a tuple containing five components, describing the Windows version
+ currently running. The elements are *major*, *minor*, *build*, *platform*, and
+ *text*. *text* contains a string while all other values are integers.
+
+ *platform* may be one of the following values:
+
+ +-----------------------------------------+-----------------------+
+ | Constant | Platform |
+ +=========================================+=======================+
+ | :const:`0 (VER_PLATFORM_WIN32s)` | Win32s on Windows 3.1 |
+ +-----------------------------------------+-----------------------+
+ | :const:`1 (VER_PLATFORM_WIN32_WINDOWS)` | Windows 95/98/ME |
+ +-----------------------------------------+-----------------------+
+ | :const:`2 (VER_PLATFORM_WIN32_NT)` | Windows NT/2000/XP |
+ +-----------------------------------------+-----------------------+
+ | :const:`3 (VER_PLATFORM_WIN32_CE)` | Windows CE |
+ +-----------------------------------------+-----------------------+
+
+ This function wraps the Win32 :cfunc:`GetVersionEx` function; see the Microsoft
+ documentation for more information about these fields.
+
+ Availability: Windows.
+
+ .. versionadded:: 2.3
+
+
+.. data:: hexversion
+
+ The version number encoded as a single integer. This is guaranteed to increase
+ with each version, including proper support for non-production releases. For
+ example, to test that the Python interpreter is at least version 1.5.2, use::
+
+ if sys.hexversion >= 0x010502F0:
+ # use some advanced feature
+ ...
+ else:
+ # use an alternative implementation or warn the user
+ ...
+
+ This is called ``hexversion`` since it only really looks meaningful when viewed
+ as the result of passing it to the built-in :func:`hex` function. The
+ ``version_info`` value may be used for a more human-friendly encoding of the
+ same information.
+
+ .. versionadded:: 1.5.2
+
+
+.. function:: intern(string)
+
+ Enter *string* in the table of "interned" strings and return the interned string
+ -- which is *string* itself or a copy. Interning strings is useful to gain a
+ little performance on dictionary lookup -- if the keys in a dictionary are
+ interned, and the lookup key is interned, the key comparisons (after hashing)
+ can be done by a pointer compare instead of a string compare. Normally, the
+ names used in Python programs are automatically interned, and the dictionaries
+ used to hold module, class or instance attributes have interned keys.
+
+ .. versionchanged:: 2.3
+ Interned strings are not immortal (like they used to be in Python 2.2 and
+ before); you must keep a reference to the return value of :func:`intern` around
+ to benefit from it.
+
+
+.. data:: last_type
+ last_value
+ last_traceback
+
+ These three variables are not always defined; they are set when an exception is
+ not handled and the interpreter prints an error message and a stack traceback.
+ Their intended use is to allow an interactive user to import a debugger module
+ and engage in post-mortem debugging without having to re-execute the command
+ that caused the error. (Typical use is ``import pdb; pdb.pm()`` to enter the
+ post-mortem debugger; see chapter :ref:`debugger` for
+ more information.)
+
+ The meaning of the variables is the same as that of the return values from
+ :func:`exc_info` above. (Since there is only one interactive thread,
+ thread-safety is not a concern for these variables, unlike for ``exc_type``
+ etc.)
+
+
+.. data:: maxint
+
+ The largest positive integer supported by Python's regular integer type. This
+ is at least 2\*\*31-1. The largest negative integer is ``-maxint-1`` --- the
+ asymmetry results from the use of 2's complement binary arithmetic.
+
+
+.. data:: maxunicode
+
+ An integer giving the largest supported code point for a Unicode character. The
+ value of this depends on the configuration option that specifies whether Unicode
+ characters are stored as UCS-2 or UCS-4.
+
+
+.. data:: modules
+
+ This is a dictionary that maps module names to modules which have already been
+ loaded. This can be manipulated to force reloading of modules and other tricks.
+
+
+.. data:: path
+
+ .. index:: triple: module; search; path
+
+ A list of strings that specifies the search path for modules. Initialized from
+ the environment variable :envvar:`PYTHONPATH`, plus an installation-dependent
+ default.
+
+ As initialized upon program startup, the first item of this list, ``path[0]``,
+ is the directory containing the script that was used to invoke the Python
+ interpreter. If the script directory is not available (e.g. if the interpreter
+ is invoked interactively or if the script is read from standard input),
+ ``path[0]`` is the empty string, which directs Python to search modules in the
+ current directory first. Notice that the script directory is inserted *before*
+ the entries inserted as a result of :envvar:`PYTHONPATH`.
+
+ A program is free to modify this list for its own purposes.
+
+ .. versionchanged:: 2.3
+ Unicode strings are no longer ignored.
+
+
+.. data:: platform
+
+ This string contains a platform identifier, e.g. ``'sunos5'`` or ``'linux1'``.
+ This can be used to append platform-specific components to ``path``, for
+ instance.
+
+
+.. data:: prefix
+
+ A string giving the site-specific directory prefix where the platform
+ independent Python files are installed; by default, this is the string
+ ``'/usr/local'``. This can be set at build time with the :option:`--prefix`
+ argument to the :program:`configure` script. The main collection of Python
+ library modules is installed in the directory ``prefix + '/lib/pythonversion'``
+ while the platform independent header files (all except :file:`pyconfig.h`) are
+ stored in ``prefix + '/include/pythonversion'``, where *version* is equal to
+ ``version[:3]``.
+
+
+.. data:: ps1
+ ps2
+
+ .. index::
+ single: interpreter prompts
+ single: prompts, interpreter
+
+ Strings specifying the primary and secondary prompt of the interpreter. These
+ are only defined if the interpreter is in interactive mode. Their initial
+ values in this case are ``'>>> '`` and ``'... '``. If a non-string object is
+ assigned to either variable, its :func:`str` is re-evaluated each time the
+ interpreter prepares to read a new interactive command; this can be used to
+ implement a dynamic prompt.
+
+
+.. function:: setcheckinterval(interval)
+
+ Set the interpreter's "check interval". This integer value determines how often
+ the interpreter checks for periodic things such as thread switches and signal
+ handlers. The default is ``100``, meaning the check is performed every 100
+ Python virtual instructions. Setting it to a larger value may increase
+ performance for programs using threads. Setting it to a value ``<=`` 0 checks
+ every virtual instruction, maximizing responsiveness as well as overhead.
+
+
+.. function:: setdefaultencoding(name)
+
+ Set the current default string encoding used by the Unicode implementation. If
+ *name* does not match any available encoding, :exc:`LookupError` is raised.
+ This function is only intended to be used by the :mod:`site` module
+ implementation and, where needed, by :mod:`sitecustomize`. Once used by the
+ :mod:`site` module, it is removed from the :mod:`sys` module's namespace.
+
+ .. % Note that \refmodule{site} is not imported if
+ .. % the \programopt{-S} option is passed to the interpreter, in which
+ .. % case this function will remain available.
+
+ .. versionadded:: 2.0
+
+
+.. function:: setdlopenflags(n)
+
+ Set the flags used by the interpreter for :cfunc:`dlopen` calls, such as when
+ the interpreter loads extension modules. Among other things, this will enable a
+ lazy resolving of symbols when importing a module, if called as
+ ``sys.setdlopenflags(0)``. To share symbols across extension modules, call as
+ ``sys.setdlopenflags(dl.RTLD_NOW | dl.RTLD_GLOBAL)``. Symbolic names for the
+ flag modules can be either found in the :mod:`dl` module, or in the :mod:`DLFCN`
+ module. If :mod:`DLFCN` is not available, it can be generated from
+ :file:`/usr/include/dlfcn.h` using the :program:`h2py` script. Availability:
+ Unix.
+
+ .. versionadded:: 2.2
+
+
+.. function:: setprofile(profilefunc)
+
+ .. index::
+ single: profile function
+ single: profiler
+
+ Set the system's profile function, which allows you to implement a Python source
+ code profiler in Python. See chapter :ref:`profile` for more information on the
+ Python profiler. The system's profile function is called similarly to the
+ system's trace function (see :func:`settrace`), but it isn't called for each
+ executed line of code (only on call and return, but the return event is reported
+ even when an exception has been set). The function is thread-specific, but
+ there is no way for the profiler to know about context switches between threads,
+ so it does not make sense to use this in the presence of multiple threads. Also,
+ its return value is not used, so it can simply return ``None``.
+
+
+.. function:: setrecursionlimit(limit)
+
+ Set the maximum depth of the Python interpreter stack to *limit*. This limit
+ prevents infinite recursion from causing an overflow of the C stack and crashing
+ Python.
+
+ The highest possible limit is platform-dependent. A user may need to set the
+ limit higher when she has a program that requires deep recursion and a platform
+ that supports a higher limit. This should be done with care, because a too-high
+ limit can lead to a crash.
+
+
+.. function:: settrace(tracefunc)
+
+ .. index::
+ single: trace function
+ single: debugger
+
+ Set the system's trace function, which allows you to implement a Python
+ source code debugger in Python. See section :ref:`debugger-hooks` in the
+ chapter on the Python debugger. The function is thread-specific; for a
+ debugger to support multiple threads, it must be registered using
+ :func:`settrace` for each thread being debugged.
+
+ .. note::
+
+ The :func:`settrace` function is intended only for implementing debuggers,
+ profilers, coverage tools and the like. Its behavior is part of the
+ implementation platform, rather than part of the language definition, and thus
+ may not be available in all Python implementations.
+
+
+.. function:: settscdump(on_flag)
+
+ Activate dumping of VM measurements using the Pentium timestamp counter, if
+ *on_flag* is true. Deactivate these dumps if *on_flag* is off. The function is
+ available only if Python was compiled with :option:`--with-tsc`. To understand
+ the output of this dump, read :file:`Python/ceval.c` in the Python sources.
+
+ .. versionadded:: 2.4
+
+
+.. data:: stdin
+ stdout
+ stderr
+
+ File objects corresponding to the interpreter's standard input, output and error
+ streams. ``stdin`` is used for all interpreter input except for scripts.
+ ``stdout`` is used for the output of :keyword:`print` and expression statements.
+ The interpreter's own prompts and (almost all of) its error messages go to
+ ``stderr``. ``stdout`` and ``stderr`` needn't be built-in file objects: any
+ object is acceptable as long as it has a :meth:`write` method that takes a
+ string argument. (Changing these objects doesn't affect the standard I/O
+ streams of processes executed by :func:`os.popen`, :func:`os.system` or the
+ :func:`exec\*` family of functions in the :mod:`os` module.)
+
+
+.. data:: __stdin__
+ __stdout__
+ __stderr__
+
+ These objects contain the original values of ``stdin``, ``stderr`` and
+ ``stdout`` at the start of the program. They are used during finalization, and
+ could be useful to restore the actual files to known working file objects in
+ case they have been overwritten with a broken object.
+
+
+.. data:: tracebacklimit
+
+ When this variable is set to an integer value, it determines the maximum number
+ of levels of traceback information printed when an unhandled exception occurs.
+ The default is ``1000``. When set to ``0`` or less, all traceback information
+ is suppressed and only the exception type and value are printed.
+
+
+.. data:: version
+
+ A string containing the version number of the Python interpreter plus additional
+ information on the build number and compiler used. It has a value of the form
+ ``'version (#build_number, build_date, build_time) [compiler]'``. The first
+ three characters are used to identify the version in the installation
+ directories (where appropriate on each platform). An example::
+
+ >>> import sys
+ >>> sys.version
+ '1.5.2 (#0 Apr 13 1999, 10:51:12) [MSC 32 bit (Intel)]'
+
+
+.. data:: api_version
+
+ The C API version for this interpreter. Programmers may find this useful when
+ debugging version conflicts between Python and extension modules.
+
+ .. versionadded:: 2.3
+
+
+.. data:: version_info
+
+ A tuple containing the five components of the version number: *major*, *minor*,
+ *micro*, *releaselevel*, and *serial*. All values except *releaselevel* are
+ integers; the release level is ``'alpha'``, ``'beta'``, ``'candidate'``, or
+ ``'final'``. The ``version_info`` value corresponding to the Python version 2.0
+ is ``(2, 0, 0, 'final', 0)``.
+
+ .. versionadded:: 2.0
+
+
+.. data:: warnoptions
+
+ This is an implementation detail of the warnings framework; do not modify this
+ value. Refer to the :mod:`warnings` module for more information on the warnings
+ framework.
+
+
+.. data:: winver
+
+ The version number used to form registry keys on Windows platforms. This is
+ stored as string resource 1000 in the Python DLL. The value is normally the
+ first three characters of :const:`version`. It is provided in the :mod:`sys`
+ module for informational purposes; modifying this value has no effect on the
+ registry keys used by Python. Availability: Windows.
+
+
+.. seealso::
+
+ Module :mod:`site`
+ This describes how to use .pth files to extend ``sys.path``.
+
diff --git a/Doc/library/syslog.rst b/Doc/library/syslog.rst
new file mode 100644
index 0000000000..549f26b008
--- /dev/null
+++ b/Doc/library/syslog.rst
@@ -0,0 +1,66 @@
+
+:mod:`syslog` --- Unix syslog library routines
+==============================================
+
+.. module:: syslog
+ :platform: Unix
+ :synopsis: An interface to the Unix syslog library routines.
+
+
+This module provides an interface to the Unix ``syslog`` library routines.
+Refer to the Unix manual pages for a detailed description of the ``syslog``
+facility.
+
+The module defines the following functions:
+
+
+.. function:: syslog([priority,] message)
+
+ Send the string *message* to the system logger. A trailing newline is added if
+ necessary. Each message is tagged with a priority composed of a *facility* and
+ a *level*. The optional *priority* argument, which defaults to
+ :const:`LOG_INFO`, determines the message priority. If the facility is not
+ encoded in *priority* using logical-or (``LOG_INFO | LOG_USER``), the value
+ given in the :func:`openlog` call is used.
+
+
+.. function:: openlog(ident[, logopt[, facility]])
+
+ Logging options other than the defaults can be set by explicitly opening the log
+ file with :func:`openlog` prior to calling :func:`syslog`. The defaults are
+ (usually) *ident* = ``'syslog'``, *logopt* = ``0``, *facility* =
+ :const:`LOG_USER`. The *ident* argument is a string which is prepended to every
+ message. The optional *logopt* argument is a bit field - see below for possible
+ values to combine. The optional *facility* argument sets the default facility
+ for messages which do not have a facility explicitly encoded.
+
+
+.. function:: closelog()
+
+ Close the log file.
+
+
+.. function:: setlogmask(maskpri)
+
+ Set the priority mask to *maskpri* and return the previous mask value. Calls to
+ :func:`syslog` with a priority level not set in *maskpri* are ignored. The
+ default is to log all priorities. The function ``LOG_MASK(pri)`` calculates the
+ mask for the individual priority *pri*. The function ``LOG_UPTO(pri)``
+ calculates the mask for all priorities up to and including *pri*.
+
+The module defines the following constants:
+
+Priority levels (high to low):
+ :const:`LOG_EMERG`, :const:`LOG_ALERT`, :const:`LOG_CRIT`, :const:`LOG_ERR`,
+ :const:`LOG_WARNING`, :const:`LOG_NOTICE`, :const:`LOG_INFO`,
+ :const:`LOG_DEBUG`.
+
+Facilities:
+ :const:`LOG_KERN`, :const:`LOG_USER`, :const:`LOG_MAIL`, :const:`LOG_DAEMON`,
+ :const:`LOG_AUTH`, :const:`LOG_LPR`, :const:`LOG_NEWS`, :const:`LOG_UUCP`,
+ :const:`LOG_CRON` and :const:`LOG_LOCAL0` to :const:`LOG_LOCAL7`.
+
+Log options:
+ :const:`LOG_PID`, :const:`LOG_CONS`, :const:`LOG_NDELAY`, :const:`LOG_NOWAIT`
+ and :const:`LOG_PERROR` if defined in ``<syslog.h>``.
+
diff --git a/Doc/library/tabnanny.rst b/Doc/library/tabnanny.rst
new file mode 100644
index 0000000000..80326557b4
--- /dev/null
+++ b/Doc/library/tabnanny.rst
@@ -0,0 +1,70 @@
+
+:mod:`tabnanny` --- Detection of ambiguous indentation
+======================================================
+
+.. module:: tabnanny
+ :synopsis: Tool for detecting white space related problems in Python source files in a
+ directory tree.
+.. moduleauthor:: Tim Peters <tim_one@users.sourceforge.net>
+.. sectionauthor:: Peter Funk <pf@artcom-gmbh.de>
+
+
+.. % rudimentary documentation based on module comments, by Peter Funk
+.. % <pf@artcom-gmbh.de>
+
+For the time being this module is intended to be called as a script. However it
+is possible to import it into an IDE and use the function :func:`check`
+described below.
+
+.. warning::
+
+ The API provided by this module is likely to change in future releases; such
+ changes may not be backward compatible.
+
+
+.. function:: check(file_or_dir)
+
+ If *file_or_dir* is a directory and not a symbolic link, then recursively
+ descend the directory tree named by *file_or_dir*, checking all :file:`.py`
+ files along the way. If *file_or_dir* is an ordinary Python source file, it is
+ checked for whitespace related problems. The diagnostic messages are written to
+ standard output using the print statement.
+
+
+.. data:: verbose
+
+ Flag indicating whether to print verbose messages. This is incremented by the
+ ``-v`` option if called as a script.
+
+
+.. data:: filename_only
+
+ Flag indicating whether to print only the filenames of files containing
+ whitespace related problems. This is set to true by the ``-q`` option if called
+ as a script.
+
+
+.. exception:: NannyNag
+
+ Raised by :func:`tokeneater` if detecting an ambiguous indent. Captured and
+ handled in :func:`check`.
+
+
+.. function:: tokeneater(type, token, start, end, line)
+
+ This function is used by :func:`check` as a callback parameter to the function
+ :func:`tokenize.tokenize`.
+
+.. % XXX FIXME: Document \function{errprint},
+.. % \function{format_witnesses} \class{Whitespace}
+.. % check_equal, indents
+.. % \function{reset_globals}
+
+
+.. seealso::
+
+ Module :mod:`tokenize`
+ Lexical scanner for Python source code.
+
+ .. % XXX may be add a reference to IDLE?
+
diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst
new file mode 100644
index 0000000000..a0cd673299
--- /dev/null
+++ b/Doc/library/tarfile.rst
@@ -0,0 +1,738 @@
+.. _tarfile-mod:
+
+:mod:`tarfile` --- Read and write tar archive files
+===================================================
+
+.. module:: tarfile
+ :synopsis: Read and write tar-format archive files.
+
+
+.. versionadded:: 2.3
+
+.. moduleauthor:: Lars Gustäbel <lars@gustaebel.de>
+.. sectionauthor:: Lars Gustäbel <lars@gustaebel.de>
+
+
+The :mod:`tarfile` module makes it possible to read and create tar archives.
+Some facts and figures:
+
+* reads and writes :mod:`gzip` and :mod:`bzip2` compressed archives.
+
+* read/write support for the POSIX.1-1988 (ustar) format.
+
+* read/write support for the GNU tar format including *longname* and *longlink*
+ extensions, read-only support for the *sparse* extension.
+
+* read/write support for the POSIX.1-2001 (pax) format.
+
+ .. versionadded:: 2.6
+
+* handles directories, regular files, hardlinks, symbolic links, fifos,
+ character devices and block devices and is able to acquire and restore file
+ information like timestamp, access permissions and owner.
+
+* can handle tape devices.
+
+
+.. function:: open(name[, mode[, fileobj[, bufsize]]], **kwargs)
+
+ Return a :class:`TarFile` object for the pathname *name*. For detailed
+ information on :class:`TarFile` objects and the keyword arguments that are
+ allowed, see :ref:`tarfile-objects`.
+
+ *mode* has to be a string of the form ``'filemode[:compression]'``, it defaults
+ to ``'r'``. Here is a full list of mode combinations:
+
+ +------------------+---------------------------------------------+
+ | mode | action |
+ +==================+=============================================+
+ | ``'r' or 'r:*'`` | Open for reading with transparent |
+ | | compression (recommended). |
+ +------------------+---------------------------------------------+
+ | ``'r:'`` | Open for reading exclusively without |
+ | | compression. |
+ +------------------+---------------------------------------------+
+ | ``'r:gz'`` | Open for reading with gzip compression. |
+ +------------------+---------------------------------------------+
+ | ``'r:bz2'`` | Open for reading with bzip2 compression. |
+ +------------------+---------------------------------------------+
+ | ``'a' or 'a:'`` | Open for appending with no compression. The |
+ | | file is created if it does not exist. |
+ +------------------+---------------------------------------------+
+ | ``'w' or 'w:'`` | Open for uncompressed writing. |
+ +------------------+---------------------------------------------+
+ | ``'w:gz'`` | Open for gzip compressed writing. |
+ +------------------+---------------------------------------------+
+ | ``'w:bz2'`` | Open for bzip2 compressed writing. |
+ +------------------+---------------------------------------------+
+
+ Note that ``'a:gz'`` or ``'a:bz2'`` is not possible. If *mode* is not suitable
+ to open a certain (compressed) file for reading, :exc:`ReadError` is raised. Use
+ *mode* ``'r'`` to avoid this. If a compression method is not supported,
+ :exc:`CompressionError` is raised.
+
+ If *fileobj* is specified, it is used as an alternative to a file object opened
+ for *name*. It is supposed to be at position 0.
+
+ For special purposes, there is a second format for *mode*:
+ ``'filemode|[compression]'``. :func:`open` will return a :class:`TarFile`
+ object that processes its data as a stream of blocks. No random seeking will
+ be done on the file. If given, *fileobj* may be any object that has a
+ :meth:`read` or :meth:`write` method (depending on the *mode*). *bufsize*
+ specifies the blocksize and defaults to ``20 * 512`` bytes. Use this variant
+ in combination with e.g. ``sys.stdin``, a socket file object or a tape
+ device. However, such a :class:`TarFile` object is limited in that it does
+ not allow to be accessed randomly, see :ref:`tar-examples`. The currently
+ possible modes:
+
+ +-------------+--------------------------------------------+
+ | Mode | Action |
+ +=============+============================================+
+ | ``'r|*'`` | Open a *stream* of tar blocks for reading |
+ | | with transparent compression. |
+ +-------------+--------------------------------------------+
+ | ``'r|'`` | Open a *stream* of uncompressed tar blocks |
+ | | for reading. |
+ +-------------+--------------------------------------------+
+ | ``'r|gz'`` | Open a gzip compressed *stream* for |
+ | | reading. |
+ +-------------+--------------------------------------------+
+ | ``'r|bz2'`` | Open a bzip2 compressed *stream* for |
+ | | reading. |
+ +-------------+--------------------------------------------+
+ | ``'w|'`` | Open an uncompressed *stream* for writing. |
+ +-------------+--------------------------------------------+
+ | ``'w|gz'`` | Open an gzip compressed *stream* for |
+ | | writing. |
+ +-------------+--------------------------------------------+
+ | ``'w|bz2'`` | Open an bzip2 compressed *stream* for |
+ | | writing. |
+ +-------------+--------------------------------------------+
+
+
+.. class:: TarFile
+
+ Class for reading and writing tar archives. Do not use this class directly,
+ better use :func:`open` instead. See :ref:`tarfile-objects`.
+
+
+.. function:: is_tarfile(name)
+
+ Return :const:`True` if *name* is a tar archive file, that the :mod:`tarfile`
+ module can read.
+
+
+.. class:: TarFileCompat(filename[, mode[, compression]])
+
+ Class for limited access to tar archives with a :mod:`zipfile`\ -like interface.
+ Please consult the documentation of the :mod:`zipfile` module for more details.
+ *compression* must be one of the following constants:
+
+
+ .. data:: TAR_PLAIN
+
+ Constant for an uncompressed tar archive.
+
+
+ .. data:: TAR_GZIPPED
+
+ Constant for a :mod:`gzip` compressed tar archive.
+
+
+.. exception:: TarError
+
+ Base class for all :mod:`tarfile` exceptions.
+
+
+.. exception:: ReadError
+
+ Is raised when a tar archive is opened, that either cannot be handled by the
+ :mod:`tarfile` module or is somehow invalid.
+
+
+.. exception:: CompressionError
+
+ Is raised when a compression method is not supported or when the data cannot be
+ decoded properly.
+
+
+.. exception:: StreamError
+
+ Is raised for the limitations that are typical for stream-like :class:`TarFile`
+ objects.
+
+
+.. exception:: ExtractError
+
+ Is raised for *non-fatal* errors when using :meth:`extract`, but only if
+ :attr:`TarFile.errorlevel`\ ``== 2``.
+
+
+.. exception:: HeaderError
+
+ Is raised by :meth:`frombuf` if the buffer it gets is invalid.
+
+ .. versionadded:: 2.6
+
+Each of the following constants defines a tar archive format that the
+:mod:`tarfile` module is able to create. See section :ref:`tar-formats` for
+details.
+
+
+.. data:: USTAR_FORMAT
+
+ POSIX.1-1988 (ustar) format.
+
+
+.. data:: GNU_FORMAT
+
+ GNU tar format.
+
+
+.. data:: PAX_FORMAT
+
+ POSIX.1-2001 (pax) format.
+
+
+.. data:: DEFAULT_FORMAT
+
+ The default format for creating archives. This is currently :const:`GNU_FORMAT`.
+
+
+.. seealso::
+
+ Module :mod:`zipfile`
+ Documentation of the :mod:`zipfile` standard module.
+
+ `GNU tar manual, Basic Tar Format <http://www.gnu.org/software/tar/manual/html_node/tar_134.html#SEC134>`_
+ Documentation for tar archive files, including GNU tar extensions.
+
+.. % -----------------
+.. % TarFile Objects
+.. % -----------------
+
+
+.. _tarfile-objects:
+
+TarFile Objects
+---------------
+
+The :class:`TarFile` object provides an interface to a tar archive. A tar
+archive is a sequence of blocks. An archive member (a stored file) is made up of
+a header block followed by data blocks. It is possible to store a file in a tar
+archive several times. Each archive member is represented by a :class:`TarInfo`
+object, see :ref:`tarinfo-objects` for details.
+
+
+.. class:: TarFile(name=None, mode='r', fileobj=None, format=DEFAULT_FORMAT, tarinfo=TarInfo, dereference=False, ignore_zeros=False, encoding=None, errors=None, pax_headers=None, debug=0, errorlevel=0)
+
+ All following arguments are optional and can be accessed as instance attributes
+ as well.
+
+ *name* is the pathname of the archive. It can be omitted if *fileobj* is given.
+ In this case, the file object's :attr:`name` attribute is used if it exists.
+
+ *mode* is either ``'r'`` to read from an existing archive, ``'a'`` to append
+ data to an existing file or ``'w'`` to create a new file overwriting an existing
+ one.
+
+ If *fileobj* is given, it is used for reading or writing data. If it can be
+ determined, *mode* is overridden by *fileobj*'s mode. *fileobj* will be used
+ from position 0.
+
+ .. note::
+
+ *fileobj* is not closed, when :class:`TarFile` is closed.
+
+ *format* controls the archive format. It must be one of the constants
+ :const:`USTAR_FORMAT`, :const:`GNU_FORMAT` or :const:`PAX_FORMAT` that are
+ defined at module level.
+
+ .. versionadded:: 2.6
+
+ The *tarinfo* argument can be used to replace the default :class:`TarInfo` class
+ with a different one.
+
+ .. versionadded:: 2.6
+
+ If *dereference* is ``False``, add symbolic and hard links to the archive. If it
+ is ``True``, add the content of the target files to the archive. This has no
+ effect on systems that do not support symbolic links.
+
+ If *ignore_zeros* is ``False``, treat an empty block as the end of the archive.
+ If it is *True*, skip empty (and invalid) blocks and try to get as many members
+ as possible. This is only useful for reading concatenated or damaged archives.
+
+ *debug* can be set from ``0`` (no debug messages) up to ``3`` (all debug
+ messages). The messages are written to ``sys.stderr``.
+
+ If *errorlevel* is ``0``, all errors are ignored when using :meth:`extract`.
+ Nevertheless, they appear as error messages in the debug output, when debugging
+ is enabled. If ``1``, all *fatal* errors are raised as :exc:`OSError` or
+ :exc:`IOError` exceptions. If ``2``, all *non-fatal* errors are raised as
+ :exc:`TarError` exceptions as well.
+
+ The *encoding* and *errors* arguments control the way strings are converted to
+ unicode objects and vice versa. The default settings will work for most users.
+ See section :ref:`tar-unicode` for in-depth information.
+
+ .. versionadded:: 2.6
+
+ The *pax_headers* argument is an optional dictionary of unicode strings which
+ will be added as a pax global header if *format* is :const:`PAX_FORMAT`.
+
+ .. versionadded:: 2.6
+
+
+.. method:: TarFile.open(...)
+
+ Alternative constructor. The :func:`open` function on module level is actually a
+ shortcut to this classmethod. See section :ref:`tarfile-mod` for details.
+
+
+.. method:: TarFile.getmember(name)
+
+ Return a :class:`TarInfo` object for member *name*. If *name* can not be found
+ in the archive, :exc:`KeyError` is raised.
+
+ .. note::
+
+ If a member occurs more than once in the archive, its last occurrence is assumed
+ to be the most up-to-date version.
+
+
+.. method:: TarFile.getmembers()
+
+ Return the members of the archive as a list of :class:`TarInfo` objects. The
+ list has the same order as the members in the archive.
+
+
+.. method:: TarFile.getnames()
+
+ Return the members as a list of their names. It has the same order as the list
+ returned by :meth:`getmembers`.
+
+
+.. method:: TarFile.list(verbose=True)
+
+ Print a table of contents to ``sys.stdout``. If *verbose* is :const:`False`,
+ only the names of the members are printed. If it is :const:`True`, output
+ similar to that of :program:`ls -l` is produced.
+
+
+.. method:: TarFile.next()
+
+ Return the next member of the archive as a :class:`TarInfo` object, when
+ :class:`TarFile` is opened for reading. Return ``None`` if there is no more
+ available.
+
+
+.. method:: TarFile.extractall([path[, members]])
+
+ Extract all members from the archive to the current working directory or
+ directory *path*. If optional *members* is given, it must be a subset of the
+ list returned by :meth:`getmembers`. Directory information like owner,
+ modification time and permissions are set after all members have been extracted.
+ This is done to work around two problems: A directory's modification time is
+ reset each time a file is created in it. And, if a directory's permissions do
+ not allow writing, extracting files to it will fail.
+
+ .. versionadded:: 2.5
+
+
+.. method:: TarFile.extract(member[, path])
+
+ Extract a member from the archive to the current working directory, using its
+ full name. Its file information is extracted as accurately as possible. *member*
+ may be a filename or a :class:`TarInfo` object. You can specify a different
+ directory using *path*.
+
+ .. note::
+
+ Because the :meth:`extract` method allows random access to a tar archive there
+ are some issues you must take care of yourself. See the description for
+ :meth:`extractall` above.
+
+
+.. method:: TarFile.extractfile(member)
+
+ Extract a member from the archive as a file object. *member* may be a filename
+ or a :class:`TarInfo` object. If *member* is a regular file, a file-like object
+ is returned. If *member* is a link, a file-like object is constructed from the
+ link's target. If *member* is none of the above, ``None`` is returned.
+
+ .. note::
+
+ The file-like object is read-only and provides the following methods:
+ :meth:`read`, :meth:`readline`, :meth:`readlines`, :meth:`seek`, :meth:`tell`.
+
+
+.. method:: TarFile.add(name[, arcname[, recursive[, exclude]]])
+
+ Add the file *name* to the archive. *name* may be any type of file (directory,
+ fifo, symbolic link, etc.). If given, *arcname* specifies an alternative name
+ for the file in the archive. Directories are added recursively by default. This
+ can be avoided by setting *recursive* to :const:`False`. If *exclude* is given
+ it must be a function that takes one filename argument and returns a boolean
+ value. Depending on this value the respective file is either excluded
+ (:const:`True`) or added (:const:`False`).
+
+ .. versionchanged:: 2.6
+ Added the *exclude* parameter.
+
+
+.. method:: TarFile.addfile(tarinfo[, fileobj])
+
+ Add the :class:`TarInfo` object *tarinfo* to the archive. If *fileobj* is given,
+ ``tarinfo.size`` bytes are read from it and added to the archive. You can
+ create :class:`TarInfo` objects using :meth:`gettarinfo`.
+
+ .. note::
+
+ On Windows platforms, *fileobj* should always be opened with mode ``'rb'`` to
+ avoid irritation about the file size.
+
+
+.. method:: TarFile.gettarinfo([name[, arcname[, fileobj]]])
+
+ Create a :class:`TarInfo` object for either the file *name* or the file object
+ *fileobj* (using :func:`os.fstat` on its file descriptor). You can modify some
+ of the :class:`TarInfo`'s attributes before you add it using :meth:`addfile`.
+ If given, *arcname* specifies an alternative name for the file in the archive.
+
+
+.. method:: TarFile.close()
+
+ Close the :class:`TarFile`. In write mode, two finishing zero blocks are
+ appended to the archive.
+
+
+.. attribute:: TarFile.posix
+
+ Setting this to :const:`True` is equivalent to setting the :attr:`format`
+ attribute to :const:`USTAR_FORMAT`, :const:`False` is equivalent to
+ :const:`GNU_FORMAT`.
+
+ .. versionchanged:: 2.4
+ *posix* defaults to :const:`False`.
+
+ .. deprecated:: 2.6
+ Use the :attr:`format` attribute instead.
+
+
+.. attribute:: TarFile.pax_headers
+
+ A dictionary containing key-value pairs of pax global headers.
+
+ .. versionadded:: 2.6
+
+.. % -----------------
+.. % TarInfo Objects
+.. % -----------------
+
+
+.. _tarinfo-objects:
+
+TarInfo Objects
+---------------
+
+A :class:`TarInfo` object represents one member in a :class:`TarFile`. Aside
+from storing all required attributes of a file (like file type, size, time,
+permissions, owner etc.), it provides some useful methods to determine its type.
+It does *not* contain the file's data itself.
+
+:class:`TarInfo` objects are returned by :class:`TarFile`'s methods
+:meth:`getmember`, :meth:`getmembers` and :meth:`gettarinfo`.
+
+
+.. class:: TarInfo([name])
+
+ Create a :class:`TarInfo` object.
+
+
+.. method:: TarInfo.frombuf(buf)
+
+ Create and return a :class:`TarInfo` object from string buffer *buf*.
+
+ .. versionadded:: 2.6
+ Raises :exc:`HeaderError` if the buffer is invalid..
+
+
+.. method:: TarInfo.fromtarfile(tarfile)
+
+ Read the next member from the :class:`TarFile` object *tarfile* and return it as
+ a :class:`TarInfo` object.
+
+ .. versionadded:: 2.6
+
+
+.. method:: TarInfo.tobuf([format[, encoding [, errors]]])
+
+ Create a string buffer from a :class:`TarInfo` object. For information on the
+ arguments see the constructor of the :class:`TarFile` class.
+
+ .. versionchanged:: 2.6
+ The arguments were added.
+
+A ``TarInfo`` object has the following public data attributes:
+
+
+.. attribute:: TarInfo.name
+
+ Name of the archive member.
+
+
+.. attribute:: TarInfo.size
+
+ Size in bytes.
+
+
+.. attribute:: TarInfo.mtime
+
+ Time of last modification.
+
+
+.. attribute:: TarInfo.mode
+
+ Permission bits.
+
+
+.. attribute:: TarInfo.type
+
+ File type. *type* is usually one of these constants: :const:`REGTYPE`,
+ :const:`AREGTYPE`, :const:`LNKTYPE`, :const:`SYMTYPE`, :const:`DIRTYPE`,
+ :const:`FIFOTYPE`, :const:`CONTTYPE`, :const:`CHRTYPE`, :const:`BLKTYPE`,
+ :const:`GNUTYPE_SPARSE`. To determine the type of a :class:`TarInfo` object
+ more conveniently, use the ``is_*()`` methods below.
+
+
+.. attribute:: TarInfo.linkname
+
+ Name of the target file name, which is only present in :class:`TarInfo` objects
+ of type :const:`LNKTYPE` and :const:`SYMTYPE`.
+
+
+.. attribute:: TarInfo.uid
+
+ User ID of the user who originally stored this member.
+
+
+.. attribute:: TarInfo.gid
+
+ Group ID of the user who originally stored this member.
+
+
+.. attribute:: TarInfo.uname
+
+ User name.
+
+
+.. attribute:: TarInfo.gname
+
+ Group name.
+
+
+.. attribute:: TarInfo.pax_headers
+
+ A dictionary containing key-value pairs of an associated pax extended header.
+
+ .. versionadded:: 2.6
+
+A :class:`TarInfo` object also provides some convenient query methods:
+
+
+.. method:: TarInfo.isfile()
+
+ Return :const:`True` if the :class:`Tarinfo` object is a regular file.
+
+
+.. method:: TarInfo.isreg()
+
+ Same as :meth:`isfile`.
+
+
+.. method:: TarInfo.isdir()
+
+ Return :const:`True` if it is a directory.
+
+
+.. method:: TarInfo.issym()
+
+ Return :const:`True` if it is a symbolic link.
+
+
+.. method:: TarInfo.islnk()
+
+ Return :const:`True` if it is a hard link.
+
+
+.. method:: TarInfo.ischr()
+
+ Return :const:`True` if it is a character device.
+
+
+.. method:: TarInfo.isblk()
+
+ Return :const:`True` if it is a block device.
+
+
+.. method:: TarInfo.isfifo()
+
+ Return :const:`True` if it is a FIFO.
+
+
+.. method:: TarInfo.isdev()
+
+ Return :const:`True` if it is one of character device, block device or FIFO.
+
+.. % ------------------------
+.. % Examples
+.. % ------------------------
+
+
+.. _tar-examples:
+
+Examples
+--------
+
+How to extract an entire tar archive to the current working directory::
+
+ import tarfile
+ tar = tarfile.open("sample.tar.gz")
+ tar.extractall()
+ tar.close()
+
+How to create an uncompressed tar archive from a list of filenames::
+
+ import tarfile
+ tar = tarfile.open("sample.tar", "w")
+ for name in ["foo", "bar", "quux"]:
+ tar.add(name)
+ tar.close()
+
+How to read a gzip compressed tar archive and display some member information::
+
+ import tarfile
+ tar = tarfile.open("sample.tar.gz", "r:gz")
+ for tarinfo in tar:
+ print tarinfo.name, "is", tarinfo.size, "bytes in size and is",
+ if tarinfo.isreg():
+ print "a regular file."
+ elif tarinfo.isdir():
+ print "a directory."
+ else:
+ print "something else."
+ tar.close()
+
+How to create a tar archive with faked information::
+
+ import tarfile
+ tar = tarfile.open("sample.tar.gz", "w:gz")
+ for name in namelist:
+ tarinfo = tar.gettarinfo(name, "fakeproj-1.0/" + name)
+ tarinfo.uid = 123
+ tarinfo.gid = 456
+ tarinfo.uname = "johndoe"
+ tarinfo.gname = "fake"
+ tar.addfile(tarinfo, file(name))
+ tar.close()
+
+The *only* way to extract an uncompressed tar stream from ``sys.stdin``::
+
+ import sys
+ import tarfile
+ tar = tarfile.open(mode="r|", fileobj=sys.stdin)
+ for tarinfo in tar:
+ tar.extract(tarinfo)
+ tar.close()
+
+.. % ------------
+.. % Tar format
+.. % ------------
+
+
+.. _tar-formats:
+
+Supported tar formats
+---------------------
+
+There are three tar formats that can be created with the :mod:`tarfile` module:
+
+* The POSIX.1-1988 ustar format (:const:`USTAR_FORMAT`). It supports filenames
+ up to a length of at best 256 characters and linknames up to 100 characters. The
+ maximum file size is 8 gigabytes. This is an old and limited but widely
+ supported format.
+
+* The GNU tar format (:const:`GNU_FORMAT`). It supports long filenames and
+ linknames, files bigger than 8 gigabytes and sparse files. It is the de facto
+ standard on GNU/Linux systems. :mod:`tarfile` fully supports the GNU tar
+ extensions for long names, sparse file support is read-only.
+
+* The POSIX.1-2001 pax format (:const:`PAX_FORMAT`). It is the most flexible
+ format with virtually no limits. It supports long filenames and linknames, large
+ files and stores pathnames in a portable way. However, not all tar
+ implementations today are able to handle pax archives properly.
+
+ The *pax* format is an extension to the existing *ustar* format. It uses extra
+ headers for information that cannot be stored otherwise. There are two flavours
+ of pax headers: Extended headers only affect the subsequent file header, global
+ headers are valid for the complete archive and affect all following files. All
+ the data in a pax header is encoded in *UTF-8* for portability reasons.
+
+There are some more variants of the tar format which can be read, but not
+created:
+
+* The ancient V7 format. This is the first tar format from Unix Seventh Edition,
+ storing only regular files and directories. Names must not be longer than 100
+ characters, there is no user/group name information. Some archives have
+ miscalculated header checksums in case of fields with non-ASCII characters.
+
+* The SunOS tar extended format. This format is a variant of the POSIX.1-2001
+ pax format, but is not compatible.
+
+.. % ----------------
+.. % Unicode issues
+.. % ----------------
+
+
+.. _tar-unicode:
+
+Unicode issues
+--------------
+
+The tar format was originally conceived to make backups on tape drives with the
+main focus on preserving file system information. Nowadays tar archives are
+commonly used for file distribution and exchanging archives over networks. One
+problem of the original format (that all other formats are merely variants of)
+is that there is no concept of supporting different character encodings. For
+example, an ordinary tar archive created on a *UTF-8* system cannot be read
+correctly on a *Latin-1* system if it contains non-ASCII characters. Names (i.e.
+filenames, linknames, user/group names) containing these characters will appear
+damaged. Unfortunately, there is no way to autodetect the encoding of an
+archive.
+
+The pax format was designed to solve this problem. It stores non-ASCII names
+using the universal character encoding *UTF-8*. When a pax archive is read,
+these *UTF-8* names are converted to the encoding of the local file system.
+
+The details of unicode conversion are controlled by the *encoding* and *errors*
+keyword arguments of the :class:`TarFile` class.
+
+The default value for *encoding* is the local character encoding. It is deduced
+from :func:`sys.getfilesystemencoding` and :func:`sys.getdefaultencoding`. In
+read mode, *encoding* is used exclusively to convert unicode names from a pax
+archive to strings in the local character encoding. In write mode, the use of
+*encoding* depends on the chosen archive format. In case of :const:`PAX_FORMAT`,
+input names that contain non-ASCII characters need to be decoded before being
+stored as *UTF-8* strings. The other formats do not make use of *encoding*
+unless unicode objects are used as input names. These are converted to 8-bit
+character strings before they are added to the archive.
+
+The *errors* argument defines how characters are treated that cannot be
+converted to or from *encoding*. Possible values are listed in section
+:ref:`codec-base-classes`. In read mode, there is an additional scheme
+``'utf-8'`` which means that bad characters are replaced by their *UTF-8*
+representation. This is the default scheme. In write mode the default value for
+*errors* is ``'strict'`` to ensure that name information is not altered
+unnoticed.
+
diff --git a/Doc/library/telnetlib.rst b/Doc/library/telnetlib.rst
new file mode 100644
index 0000000000..f6ab852c61
--- /dev/null
+++ b/Doc/library/telnetlib.rst
@@ -0,0 +1,246 @@
+
+:mod:`telnetlib` --- Telnet client
+==================================
+
+.. module:: telnetlib
+ :synopsis: Telnet client class.
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+.. index:: single: protocol; Telnet
+
+The :mod:`telnetlib` module provides a :class:`Telnet` class that implements the
+Telnet protocol. See :rfc:`854` for details about the protocol. In addition, it
+provides symbolic constants for the protocol characters (see below), and for the
+telnet options. The symbolic names of the telnet options follow the definitions
+in ``arpa/telnet.h``, with the leading ``TELOPT_`` removed. For symbolic names
+of options which are traditionally not included in ``arpa/telnet.h``, see the
+module source itself.
+
+The symbolic constants for the telnet commands are: IAC, DONT, DO, WONT, WILL,
+SE (Subnegotiation End), NOP (No Operation), DM (Data Mark), BRK (Break), IP
+(Interrupt process), AO (Abort output), AYT (Are You There), EC (Erase
+Character), EL (Erase Line), GA (Go Ahead), SB (Subnegotiation Begin).
+
+
+.. class:: Telnet([host[, port[, timeout]]])
+
+ :class:`Telnet` represents a connection to a Telnet server. The instance is
+ initially not connected by default; the :meth:`open` method must be used to
+ establish a connection. Alternatively, the host name and optional port number
+ can be passed to the constructor, to, in which case the connection to the server
+ will be established before the constructor returns. The optional *timeout*
+ parameter specifies a timeout in seconds for the connection attempt (if not
+ specified, or passed as None, the global default timeout setting will be used).
+
+ Do not reopen an already connected instance.
+
+ This class has many :meth:`read_\*` methods. Note that some of them raise
+ :exc:`EOFError` when the end of the connection is read, because they can return
+ an empty string for other reasons. See the individual descriptions below.
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. seealso::
+
+ :rfc:`854` - Telnet Protocol Specification
+ Definition of the Telnet protocol.
+
+
+.. _telnet-objects:
+
+Telnet Objects
+--------------
+
+:class:`Telnet` instances have the following methods:
+
+
+.. method:: Telnet.read_until(expected[, timeout])
+
+ Read until a given string, *expected*, is encountered or until *timeout* seconds
+ have passed.
+
+ When no match is found, return whatever is available instead, possibly the empty
+ string. Raise :exc:`EOFError` if the connection is closed and no cooked data is
+ available.
+
+
+.. method:: Telnet.read_all()
+
+ Read all data until EOF; block until connection closed.
+
+
+.. method:: Telnet.read_some()
+
+ Read at least one byte of cooked data unless EOF is hit. Return ``''`` if EOF is
+ hit. Block if no data is immediately available.
+
+
+.. method:: Telnet.read_very_eager()
+
+ Read everything that can be without blocking in I/O (eager).
+
+ Raise :exc:`EOFError` if connection closed and no cooked data available. Return
+ ``''`` if no cooked data available otherwise. Do not block unless in the midst
+ of an IAC sequence.
+
+
+.. method:: Telnet.read_eager()
+
+ Read readily available data.
+
+ Raise :exc:`EOFError` if connection closed and no cooked data available. Return
+ ``''`` if no cooked data available otherwise. Do not block unless in the midst
+ of an IAC sequence.
+
+
+.. method:: Telnet.read_lazy()
+
+ Process and return data already in the queues (lazy).
+
+ Raise :exc:`EOFError` if connection closed and no data available. Return ``''``
+ if no cooked data available otherwise. Do not block unless in the midst of an
+ IAC sequence.
+
+
+.. method:: Telnet.read_very_lazy()
+
+ Return any data available in the cooked queue (very lazy).
+
+ Raise :exc:`EOFError` if connection closed and no data available. Return ``''``
+ if no cooked data available otherwise. This method never blocks.
+
+
+.. method:: Telnet.read_sb_data()
+
+ Return the data collected between a SB/SE pair (suboption begin/end). The
+ callback should access these data when it was invoked with a ``SE`` command.
+ This method never blocks.
+
+ .. versionadded:: 2.3
+
+
+.. method:: Telnet.open(host[, port[, timeout]])
+
+ Connect to a host. The optional second argument is the port number, which
+ defaults to the standard Telnet port (23). The optional *timeout* parameter
+ specifies a timeout in seconds for the connection attempt (if not specified, or
+ passed as None, the global default timeout setting will be used).
+
+ Do not try to reopen an already connected instance.
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. method:: Telnet.msg(msg[, *args])
+
+ Print a debug message when the debug level is ``>`` 0. If extra arguments are
+ present, they are substituted in the message using the standard string
+ formatting operator.
+
+
+.. method:: Telnet.set_debuglevel(debuglevel)
+
+ Set the debug level. The higher the value of *debuglevel*, the more debug
+ output you get (on ``sys.stdout``).
+
+
+.. method:: Telnet.close()
+
+ Close the connection.
+
+
+.. method:: Telnet.get_socket()
+
+ Return the socket object used internally.
+
+
+.. method:: Telnet.fileno()
+
+ Return the file descriptor of the socket object used internally.
+
+
+.. method:: Telnet.write(buffer)
+
+ Write a string to the socket, doubling any IAC characters. This can block if the
+ connection is blocked. May raise :exc:`socket.error` if the connection is
+ closed.
+
+
+.. method:: Telnet.interact()
+
+ Interaction function, emulates a very dumb Telnet client.
+
+
+.. method:: Telnet.mt_interact()
+
+ Multithreaded version of :meth:`interact`.
+
+
+.. method:: Telnet.expect(list[, timeout])
+
+ Read until one from a list of a regular expressions matches.
+
+ The first argument is a list of regular expressions, either compiled
+ (:class:`re.RegexObject` instances) or uncompiled (strings). The optional second
+ argument is a timeout, in seconds; the default is to block indefinitely.
+
+ Return a tuple of three items: the index in the list of the first regular
+ expression that matches; the match object returned; and the text read up till
+ and including the match.
+
+ If end of file is found and no text was read, raise :exc:`EOFError`. Otherwise,
+ when nothing matches, return ``(-1, None, text)`` where *text* is the text
+ received so far (may be the empty string if a timeout happened).
+
+ If a regular expression ends with a greedy match (such as ``.*``) or if more
+ than one expression can match the same input, the results are indeterministic,
+ and may depend on the I/O timing.
+
+
+.. method:: Telnet.set_option_negotiation_callback(callback)
+
+ Each time a telnet option is read on the input flow, this *callback* (if set) is
+ called with the following parameters : callback(telnet socket, command
+ (DO/DONT/WILL/WONT), option). No other action is done afterwards by telnetlib.
+
+
+.. _telnet-example:
+
+Telnet Example
+--------------
+
+.. sectionauthor:: Peter Funk <pf@artcom-gmbh.de>
+
+
+A simple example illustrating typical use::
+
+ import getpass
+ import sys
+ import telnetlib
+
+ def raw_input(prompt):
+ sys.stdout.write(prompt)
+ sys.stdout.flush()
+ return sys.stdin.readline()
+
+ HOST = "localhost"
+ user = raw_input("Enter your remote account: ")
+ password = getpass.getpass()
+
+ tn = telnetlib.Telnet(HOST)
+
+ tn.read_until("login: ")
+ tn.write(user + "\n")
+ if password:
+ tn.read_until("Password: ")
+ tn.write(password + "\n")
+
+ tn.write("ls\n")
+ tn.write("exit\n")
+
+ print tn.read_all()
+
diff --git a/Doc/library/tempfile.rst b/Doc/library/tempfile.rst
new file mode 100644
index 0000000000..cafdd05e83
--- /dev/null
+++ b/Doc/library/tempfile.rst
@@ -0,0 +1,216 @@
+
+:mod:`tempfile` --- Generate temporary files and directories
+============================================================
+
+.. sectionauthor:: Zack Weinberg <zack@codesourcery.com>
+
+
+.. module:: tempfile
+ :synopsis: Generate temporary files and directories.
+
+
+.. index::
+ pair: temporary; file name
+ pair: temporary; file
+
+This module generates temporary files and directories. It works on all
+supported platforms.
+
+In version 2.3 of Python, this module was overhauled for enhanced security. It
+now provides three new functions, :func:`NamedTemporaryFile`, :func:`mkstemp`,
+and :func:`mkdtemp`, which should eliminate all remaining need to use the
+insecure :func:`mktemp` function. Temporary file names created by this module
+no longer contain the process ID; instead a string of six random characters is
+used.
+
+Also, all the user-callable functions now take additional arguments which allow
+direct control over the location and name of temporary files. It is no longer
+necessary to use the global *tempdir* and *template* variables. To maintain
+backward compatibility, the argument order is somewhat odd; it is recommended to
+use keyword arguments for clarity.
+
+The module defines the following user-callable functions:
+
+
+.. function:: TemporaryFile([mode='w+b'[, bufsize=-1[, suffix[, prefix[, dir]]]]])
+
+ Return a file (or file-like) object that can be used as a temporary storage
+ area. The file is created using :func:`mkstemp`. It will be destroyed as soon
+ as it is closed (including an implicit close when the object is garbage
+ collected). Under Unix, the directory entry for the file is removed immediately
+ after the file is created. Other platforms do not support this; your code
+ should not rely on a temporary file created using this function having or not
+ having a visible name in the file system.
+
+ The *mode* parameter defaults to ``'w+b'`` so that the file created can be read
+ and written without being closed. Binary mode is used so that it behaves
+ consistently on all platforms without regard for the data that is stored.
+ *bufsize* defaults to ``-1``, meaning that the operating system default is used.
+
+ The *dir*, *prefix* and *suffix* parameters are passed to :func:`mkstemp`.
+
+
+.. function:: NamedTemporaryFile([mode='w+b'[, bufsize=-1[, suffix[, prefix[, dir[, delete]]]]]])
+
+ This function operates exactly as :func:`TemporaryFile` does, except that the
+ file is guaranteed to have a visible name in the file system (on Unix, the
+ directory entry is not unlinked). That name can be retrieved from the
+ :attr:`name` member of the file object. Whether the name can be used to open
+ the file a second time, while the named temporary file is still open, varies
+ across platforms (it can be so used on Unix; it cannot on Windows NT or later).
+ If *delete* is true (the default), the file is deleted as soon as it is closed.
+
+ .. versionadded:: 2.3
+
+ .. versionadded:: 2.6
+ The *delete* parameter.
+
+
+.. function:: SpooledTemporaryFile([max_size=0, [mode='w+b'[, bufsize=-1[, suffix[, prefix[, dir]]]]]])
+
+ This function operates exactly as :func:`TemporaryFile` does, except that data
+ is spooled in memory until the file size exceeds *max_size*, or until the file's
+ :func:`fileno` method is called, at which point the contents are written to disk
+ and operation proceeds as with :func:`TemporaryFile`.
+
+ The resulting file has one additional method, :func:`rollover`, which causes the
+ file to roll over to an on-disk file regardless of its size.
+
+ .. versionadded:: 2.6
+
+
+.. function:: mkstemp([suffix[, prefix[, dir[, text]]]])
+
+ Creates a temporary file in the most secure manner possible. There are no
+ race conditions in the file's creation, assuming that the platform properly
+ implements the :const:`os.O_EXCL` flag for :func:`os.open`. The file is
+ readable and writable only by the creating user ID. If the platform uses
+ permission bits to indicate whether a file is executable, the file is
+ executable by no one. The file descriptor is not inherited by child
+ processes.
+
+ Unlike :func:`TemporaryFile`, the user of :func:`mkstemp` is responsible for
+ deleting the temporary file when done with it.
+
+ If *suffix* is specified, the file name will end with that suffix, otherwise
+ there will be no suffix. :func:`mkstemp` does not put a dot between the file
+ name and the suffix; if you need one, put it at the beginning of *suffix*.
+
+ If *prefix* is specified, the file name will begin with that prefix; otherwise,
+ a default prefix is used.
+
+ If *dir* is specified, the file will be created in that directory; otherwise,
+ a default directory is used. The default directory is chosen from a
+ platform-dependent list, but the user of the application can control the
+ directory location by setting the *TMPDIR*, *TEMP* or *TMP* environment
+ variables. There is thus no guarantee that the generated filename will have
+ any nice properties, such as not requiring quoting when passed to external
+ commands via ``os.popen()``.
+
+ If *text* is specified, it indicates whether to open the file in binary mode
+ (the default) or text mode. On some platforms, this makes no difference.
+
+ :func:`mkstemp` returns a tuple containing an OS-level handle to an open file
+ (as would be returned by :func:`os.open`) and the absolute pathname of that
+ file, in that order.
+
+ .. versionadded:: 2.3
+
+
+.. function:: mkdtemp([suffix[, prefix[, dir]]])
+
+ Creates a temporary directory in the most secure manner possible. There are no
+ race conditions in the directory's creation. The directory is readable,
+ writable, and searchable only by the creating user ID.
+
+ The user of :func:`mkdtemp` is responsible for deleting the temporary directory
+ and its contents when done with it.
+
+ The *prefix*, *suffix*, and *dir* arguments are the same as for :func:`mkstemp`.
+
+ :func:`mkdtemp` returns the absolute pathname of the new directory.
+
+ .. versionadded:: 2.3
+
+
+.. function:: mktemp([suffix[, prefix[, dir]]])
+
+ .. deprecated:: 2.3
+ Use :func:`mkstemp` instead.
+
+ Return an absolute pathname of a file that did not exist at the time the call is
+ made. The *prefix*, *suffix*, and *dir* arguments are the same as for
+ :func:`mkstemp`.
+
+ .. warning::
+
+ Use of this function may introduce a security hole in your program. By the time
+ you get around to doing anything with the file name it returns, someone else may
+ have beaten you to the punch.
+
+The module uses two global variables that tell it how to construct a temporary
+name. They are initialized at the first call to any of the functions above.
+The caller may change them, but this is discouraged; use the appropriate
+function arguments, instead.
+
+
+.. data:: tempdir
+
+ When set to a value other than ``None``, this variable defines the default value
+ for the *dir* argument to all the functions defined in this module.
+
+ If ``tempdir`` is unset or ``None`` at any call to any of the above functions,
+ Python searches a standard list of directories and sets *tempdir* to the first
+ one which the calling user can create files in. The list is:
+
+ #. The directory named by the :envvar:`TMPDIR` environment variable.
+
+ #. The directory named by the :envvar:`TEMP` environment variable.
+
+ #. The directory named by the :envvar:`TMP` environment variable.
+
+ #. A platform-specific location:
+
+ * On RiscOS, the directory named by the :envvar:`Wimp$ScrapDir` environment
+ variable.
+
+ * On Windows, the directories :file:`C:\\TEMP`, :file:`C:\\TMP`,
+ :file:`\\TEMP`, and :file:`\\TMP`, in that order.
+
+ * On all other platforms, the directories :file:`/tmp`, :file:`/var/tmp`, and
+ :file:`/usr/tmp`, in that order.
+
+ #. As a last resort, the current working directory.
+
+
+.. function:: gettempdir()
+
+ Return the directory currently selected to create temporary files in. If
+ :data:`tempdir` is not ``None``, this simply returns its contents; otherwise,
+ the search described above is performed, and the result returned.
+
+
+.. data:: template
+
+ .. deprecated:: 2.0
+ Use :func:`gettempprefix` instead.
+
+ When set to a value other than ``None``, this variable defines the prefix of the
+ final component of the filenames returned by :func:`mktemp`. A string of six
+ random letters and digits is appended to the prefix to make the filename unique.
+ On Windows, the default prefix is :file:`~T`; on all other systems it is
+ :file:`tmp`.
+
+ Older versions of this module used to require that ``template`` be set to
+ ``None`` after a call to :func:`os.fork`; this has not been necessary since
+ version 1.5.2.
+
+
+.. function:: gettempprefix()
+
+ Return the filename prefix used to create temporary files. This does not
+ contain the directory component. Using this function is preferred over reading
+ the *template* variable directly.
+
+ .. versionadded:: 1.5.2
+
diff --git a/Doc/library/termios.rst b/Doc/library/termios.rst
new file mode 100644
index 0000000000..695faade06
--- /dev/null
+++ b/Doc/library/termios.rst
@@ -0,0 +1,111 @@
+
+:mod:`termios` --- POSIX style tty control
+==========================================
+
+.. module:: termios
+ :platform: Unix
+ :synopsis: POSIX style tty control.
+
+
+.. index::
+ pair: POSIX; I/O control
+ pair: tty; I/O control
+
+This module provides an interface to the POSIX calls for tty I/O control. For a
+complete description of these calls, see the POSIX or Unix manual pages. It is
+only available for those Unix versions that support POSIX *termios* style tty
+I/O control (and then only if configured at installation time).
+
+All functions in this module take a file descriptor *fd* as their first
+argument. This can be an integer file descriptor, such as returned by
+``sys.stdin.fileno()``, or a file object, such as ``sys.stdin`` itself.
+
+This module also defines all the constants needed to work with the functions
+provided here; these have the same name as their counterparts in C. Please
+refer to your system documentation for more information on using these terminal
+control interfaces.
+
+The module defines the following functions:
+
+
+.. function:: tcgetattr(fd)
+
+ Return a list containing the tty attributes for file descriptor *fd*, as
+ follows: ``[iflag, oflag, cflag, lflag, ispeed, ospeed, cc]`` where *cc* is a
+ list of the tty special characters (each a string of length 1, except the
+ items with indices :const:`VMIN` and :const:`VTIME`, which are integers when
+ these fields are defined). The interpretation of the flags and the speeds as
+ well as the indexing in the *cc* array must be done using the symbolic
+ constants defined in the :mod:`termios` module.
+
+
+.. function:: tcsetattr(fd, when, attributes)
+
+ Set the tty attributes for file descriptor *fd* from the *attributes*, which is
+ a list like the one returned by :func:`tcgetattr`. The *when* argument
+ determines when the attributes are changed: :const:`TCSANOW` to change
+ immediately, :const:`TCSADRAIN` to change after transmitting all queued output,
+ or :const:`TCSAFLUSH` to change after transmitting all queued output and
+ discarding all queued input.
+
+
+.. function:: tcsendbreak(fd, duration)
+
+ Send a break on file descriptor *fd*. A zero *duration* sends a break for 0.25
+ --0.5 seconds; a nonzero *duration* has a system dependent meaning.
+
+
+.. function:: tcdrain(fd)
+
+ Wait until all output written to file descriptor *fd* has been transmitted.
+
+
+.. function:: tcflush(fd, queue)
+
+ Discard queued data on file descriptor *fd*. The *queue* selector specifies
+ which queue: :const:`TCIFLUSH` for the input queue, :const:`TCOFLUSH` for the
+ output queue, or :const:`TCIOFLUSH` for both queues.
+
+
+.. function:: tcflow(fd, action)
+
+ Suspend or resume input or output on file descriptor *fd*. The *action*
+ argument can be :const:`TCOOFF` to suspend output, :const:`TCOON` to restart
+ output, :const:`TCIOFF` to suspend input, or :const:`TCION` to restart input.
+
+
+.. seealso::
+
+ Module :mod:`tty`
+ Convenience functions for common terminal control operations.
+
+
+Example
+-------
+
+.. _termios-example:
+
+Here's a function that prompts for a password with echoing turned off. Note the
+technique using a separate :func:`tcgetattr` call and a :keyword:`try` ...
+:keyword:`finally` statement to ensure that the old tty attributes are restored
+exactly no matter what happens::
+
+ def raw_input(prompt):
+ import sys
+ sys.stdout.write(prompt)
+ sys.stdout.flush()
+ return sys.stdin.readline()
+
+ def getpass(prompt = "Password: "):
+ import termios, sys
+ fd = sys.stdin.fileno()
+ old = termios.tcgetattr(fd)
+ new = termios.tcgetattr(fd)
+ new[3] = new[3] & ~termios.ECHO # lflags
+ try:
+ termios.tcsetattr(fd, termios.TCSADRAIN, new)
+ passwd = raw_input(prompt)
+ finally:
+ termios.tcsetattr(fd, termios.TCSADRAIN, old)
+ return passwd
+
diff --git a/Doc/library/test.rst b/Doc/library/test.rst
new file mode 100644
index 0000000000..897209140d
--- /dev/null
+++ b/Doc/library/test.rst
@@ -0,0 +1,317 @@
+
+:mod:`test` --- Regression tests package for Python
+===================================================
+
+.. module:: test
+ :synopsis: Regression tests package containing the testing suite for Python.
+.. sectionauthor:: Brett Cannon <brett@python.org>
+
+
+The :mod:`test` package contains all regression tests for Python as well as the
+modules :mod:`test.test_support` and :mod:`test.regrtest`.
+:mod:`test.test_support` is used to enhance your tests while
+:mod:`test.regrtest` drives the testing suite.
+
+Each module in the :mod:`test` package whose name starts with ``test_`` is a
+testing suite for a specific module or feature. All new tests should be written
+using the :mod:`unittest` or :mod:`doctest` module. Some older tests are
+written using a "traditional" testing style that compares output printed to
+``sys.stdout``; this style of test is considered deprecated.
+
+
+.. seealso::
+
+ Module :mod:`unittest`
+ Writing PyUnit regression tests.
+
+ Module :mod:`doctest`
+ Tests embedded in documentation strings.
+
+
+.. _writing-tests:
+
+Writing Unit Tests for the :mod:`test` package
+----------------------------------------------
+
+.. %
+
+It is preferred that tests that use the :mod:`unittest` module follow a few
+guidelines. One is to name the test module by starting it with ``test_`` and end
+it with the name of the module being tested. The test methods in the test module
+should start with ``test_`` and end with a description of what the method is
+testing. This is needed so that the methods are recognized by the test driver as
+test methods. Also, no documentation string for the method should be included. A
+comment (such as ``# Tests function returns only True or False``) should be used
+to provide documentation for test methods. This is done because documentation
+strings get printed out if they exist and thus what test is being run is not
+stated.
+
+A basic boilerplate is often used::
+
+ import unittest
+ from test import test_support
+
+ class MyTestCase1(unittest.TestCase):
+
+ # Only use setUp() and tearDown() if necessary
+
+ def setUp(self):
+ ... code to execute in preparation for tests ...
+
+ def tearDown(self):
+ ... code to execute to clean up after tests ...
+
+ def test_feature_one(self):
+ # Test feature one.
+ ... testing code ...
+
+ def test_feature_two(self):
+ # Test feature two.
+ ... testing code ...
+
+ ... more test methods ...
+
+ class MyTestCase2(unittest.TestCase):
+ ... same structure as MyTestCase1 ...
+
+ ... more test classes ...
+
+ def test_main():
+ test_support.run_unittest(MyTestCase1,
+ MyTestCase2,
+ ... list other tests ...
+ )
+
+ if __name__ == '__main__':
+ test_main()
+
+This boilerplate code allows the testing suite to be run by :mod:`test.regrtest`
+as well as on its own as a script.
+
+The goal for regression testing is to try to break code. This leads to a few
+guidelines to be followed:
+
+* The testing suite should exercise all classes, functions, and constants. This
+ includes not just the external API that is to be presented to the outside world
+ but also "private" code.
+
+* Whitebox testing (examining the code being tested when the tests are being
+ written) is preferred. Blackbox testing (testing only the published user
+ interface) is not complete enough to make sure all boundary and edge cases are
+ tested.
+
+* Make sure all possible values are tested including invalid ones. This makes
+ sure that not only all valid values are acceptable but also that improper values
+ are handled correctly.
+
+* Exhaust as many code paths as possible. Test where branching occurs and thus
+ tailor input to make sure as many different paths through the code are taken.
+
+* Add an explicit test for any bugs discovered for the tested code. This will
+ make sure that the error does not crop up again if the code is changed in the
+ future.
+
+* Make sure to clean up after your tests (such as close and remove all temporary
+ files).
+
+* If a test is dependent on a specific condition of the operating system then
+ verify the condition already exists before attempting the test.
+
+* Import as few modules as possible and do it as soon as possible. This
+ minimizes external dependencies of tests and also minimizes possible anomalous
+ behavior from side-effects of importing a module.
+
+* Try to maximize code reuse. On occasion, tests will vary by something as small
+ as what type of input is used. Minimize code duplication by subclassing a basic
+ test class with a class that specifies the input::
+
+ class TestFuncAcceptsSequences(unittest.TestCase):
+
+ func = mySuperWhammyFunction
+
+ def test_func(self):
+ self.func(self.arg)
+
+ class AcceptLists(TestFuncAcceptsSequences):
+ arg = [1,2,3]
+
+ class AcceptStrings(TestFuncAcceptsSequences):
+ arg = 'abc'
+
+ class AcceptTuples(TestFuncAcceptsSequences):
+ arg = (1,2,3)
+
+
+.. seealso::
+
+ Test Driven Development
+ A book by Kent Beck on writing tests before code.
+
+
+.. _regrtest:
+
+Running tests using :mod:`test.regrtest`
+----------------------------------------
+
+:mod:`test.regrtest` can be used as a script to drive Python's regression test
+suite. Running the script by itself automatically starts running all regression
+tests in the :mod:`test` package. It does this by finding all modules in the
+package whose name starts with ``test_``, importing them, and executing the
+function :func:`test_main` if present. The names of tests to execute may also be
+passed to the script. Specifying a single regression test (:program:`python
+regrtest.py` :option:`test_spam.py`) will minimize output and only print whether
+the test passed or failed and thus minimize output.
+
+Running :mod:`test.regrtest` directly allows what resources are available for
+tests to use to be set. You do this by using the :option:`-u` command-line
+option. Run :program:`python regrtest.py` :option:`-uall` to turn on all
+resources; specifying :option:`all` as an option for :option:`-u` enables all
+possible resources. If all but one resource is desired (a more common case), a
+comma-separated list of resources that are not desired may be listed after
+:option:`all`. The command :program:`python regrtest.py`
+:option:`-uall,-audio,-largefile` will run :mod:`test.regrtest` with all
+resources except the :option:`audio` and :option:`largefile` resources. For a
+list of all resources and more command-line options, run :program:`python
+regrtest.py` :option:`-h`.
+
+Some other ways to execute the regression tests depend on what platform the
+tests are being executed on. On Unix, you can run :program:`make` :option:`test`
+at the top-level directory where Python was built. On Windows, executing
+:program:`rt.bat` from your :file:`PCBuild` directory will run all regression
+tests.
+
+
+:mod:`test.test_support` --- Utility functions for tests
+========================================================
+
+.. module:: test.test_support
+ :synopsis: Support for Python regression tests.
+
+
+The :mod:`test.test_support` module provides support for Python's regression
+tests.
+
+This module defines the following exceptions:
+
+
+.. exception:: TestFailed
+
+ Exception to be raised when a test fails. This is deprecated in favor of
+ :mod:`unittest`\ -based tests and :class:`unittest.TestCase`'s assertion
+ methods.
+
+
+.. exception:: TestSkipped
+
+ Subclass of :exc:`TestFailed`. Raised when a test is skipped. This occurs when a
+ needed resource (such as a network connection) is not available at the time of
+ testing.
+
+
+.. exception:: ResourceDenied
+
+ Subclass of :exc:`TestSkipped`. Raised when a resource (such as a network
+ connection) is not available. Raised by the :func:`requires` function.
+
+The :mod:`test.test_support` module defines the following constants:
+
+
+.. data:: verbose
+
+ :const:`True` when verbose output is enabled. Should be checked when more
+ detailed information is desired about a running test. *verbose* is set by
+ :mod:`test.regrtest`.
+
+
+.. data:: have_unicode
+
+ :const:`True` when Unicode support is available.
+
+
+.. data:: is_jython
+
+ :const:`True` if the running interpreter is Jython.
+
+
+.. data:: TESTFN
+
+ Set to the path that a temporary file may be created at. Any temporary that is
+ created should be closed and unlinked (removed).
+
+The :mod:`test.test_support` module defines the following functions:
+
+
+.. function:: forget(module_name)
+
+ Removes the module named *module_name* from ``sys.modules`` and deletes any
+ byte-compiled files of the module.
+
+
+.. function:: is_resource_enabled(resource)
+
+ Returns :const:`True` if *resource* is enabled and available. The list of
+ available resources is only set when :mod:`test.regrtest` is executing the
+ tests.
+
+
+.. function:: requires(resource[, msg])
+
+ Raises :exc:`ResourceDenied` if *resource* is not available. *msg* is the
+ argument to :exc:`ResourceDenied` if it is raised. Always returns true if called
+ by a function whose ``__name__`` is ``'__main__'``. Used when tests are executed
+ by :mod:`test.regrtest`.
+
+
+.. function:: findfile(filename)
+
+ Return the path to the file named *filename*. If no match is found *filename* is
+ returned. This does not equal a failure since it could be the path to the file.
+
+
+.. function:: run_unittest(*classes)
+
+ Execute :class:`unittest.TestCase` subclasses passed to the function. The
+ function scans the classes for methods starting with the prefix ``test_`` and
+ executes the tests individually.
+
+ It is also legal to pass strings as parameters; these should be keys in
+ ``sys.modules``. Each associated module will be scanned by
+ ``unittest.TestLoader.loadTestsFromModule()``. This is usually seen in the
+ following :func:`test_main` function::
+
+ def test_main():
+ test_support.run_unittest(__name__)
+
+ This will run all tests defined in the named module.
+
+The :mod:`test.test_support` module defines the following classes:
+
+
+.. class:: TransientResource(exc[, **kwargs])
+
+ Instances are a context manager that raises :exc:`ResourceDenied` if the
+ specified exception type is raised. Any keyword arguments are treated as
+ attribute/value pairs to be compared against any exception raised within the
+ :keyword:`with` statement. Only if all pairs match properly against
+ attributes on the exception is :exc:`ResourceDenied` raised.
+
+ .. versionadded:: 2.6
+
+
+.. class:: EnvironmentVarGuard()
+
+ Class used to temporarily set or unset environment variables. Instances can be
+ used as a context manager.
+
+ .. versionadded:: 2.6
+
+
+.. method:: EnvironmentVarGuard.set(envvar, value)
+
+ Temporarily set the environment variable ``envvar`` to the value of ``value``.
+
+
+.. method:: EnvironmentVarGuard.unset(envvar)
+
+ Temporarily unset the environment variable ``envvar``.
+
diff --git a/Doc/library/textwrap.rst b/Doc/library/textwrap.rst
new file mode 100644
index 0000000000..f729a64dd1
--- /dev/null
+++ b/Doc/library/textwrap.rst
@@ -0,0 +1,192 @@
+
+:mod:`textwrap` --- Text wrapping and filling
+=============================================
+
+.. module:: textwrap
+ :synopsis: Text wrapping and filling
+.. moduleauthor:: Greg Ward <gward@python.net>
+.. sectionauthor:: Greg Ward <gward@python.net>
+
+
+.. versionadded:: 2.3
+
+The :mod:`textwrap` module provides two convenience functions, :func:`wrap` and
+:func:`fill`, as well as :class:`TextWrapper`, the class that does all the work,
+and a utility function :func:`dedent`. If you're just wrapping or filling one
+or two text strings, the convenience functions should be good enough;
+otherwise, you should use an instance of :class:`TextWrapper` for efficiency.
+
+
+.. function:: wrap(text[, width[, ...]])
+
+ Wraps the single paragraph in *text* (a string) so every line is at most *width*
+ characters long. Returns a list of output lines, without final newlines.
+
+ Optional keyword arguments correspond to the instance attributes of
+ :class:`TextWrapper`, documented below. *width* defaults to ``70``.
+
+
+.. function:: fill(text[, width[, ...]])
+
+ Wraps the single paragraph in *text*, and returns a single string containing the
+ wrapped paragraph. :func:`fill` is shorthand for ::
+
+ "\n".join(wrap(text, ...))
+
+ In particular, :func:`fill` accepts exactly the same keyword arguments as
+ :func:`wrap`.
+
+Both :func:`wrap` and :func:`fill` work by creating a :class:`TextWrapper`
+instance and calling a single method on it. That instance is not reused, so for
+applications that wrap/fill many text strings, it will be more efficient for you
+to create your own :class:`TextWrapper` object.
+
+An additional utility function, :func:`dedent`, is provided to remove
+indentation from strings that have unwanted whitespace to the left of the text.
+
+
+.. function:: dedent(text)
+
+ Remove any common leading whitespace from every line in *text*.
+
+ This can be used to make triple-quoted strings line up with the left edge of the
+ display, while still presenting them in the source code in indented form.
+
+ Note that tabs and spaces are both treated as whitespace, but they are not
+ equal: the lines ``" hello"`` and ``"\thello"`` are considered to have no
+ common leading whitespace. (This behaviour is new in Python 2.5; older versions
+ of this module incorrectly expanded tabs before searching for common leading
+ whitespace.)
+
+ For example::
+
+ def test():
+ # end first line with \ to avoid the empty line!
+ s = '''\
+ hello
+ world
+ '''
+ print repr(s) # prints ' hello\n world\n '
+ print repr(dedent(s)) # prints 'hello\n world\n'
+
+
+.. class:: TextWrapper(...)
+
+ The :class:`TextWrapper` constructor accepts a number of optional keyword
+ arguments. Each argument corresponds to one instance attribute, so for example
+ ::
+
+ wrapper = TextWrapper(initial_indent="* ")
+
+ is the same as ::
+
+ wrapper = TextWrapper()
+ wrapper.initial_indent = "* "
+
+ You can re-use the same :class:`TextWrapper` object many times, and you can
+ change any of its options through direct assignment to instance attributes
+ between uses.
+
+The :class:`TextWrapper` instance attributes (and keyword arguments to the
+constructor) are as follows:
+
+
+.. attribute:: TextWrapper.width
+
+ (default: ``70``) The maximum length of wrapped lines. As long as there are no
+ individual words in the input text longer than :attr:`width`,
+ :class:`TextWrapper` guarantees that no output line will be longer than
+ :attr:`width` characters.
+
+
+.. attribute:: TextWrapper.expand_tabs
+
+ (default: ``True``) If true, then all tab characters in *text* will be expanded
+ to spaces using the :meth:`expandtabs` method of *text*.
+
+
+.. attribute:: TextWrapper.replace_whitespace
+
+ (default: ``True``) If true, each whitespace character (as defined by
+ ``string.whitespace``) remaining after tab expansion will be replaced by a
+ single space.
+
+ .. note::
+
+ If :attr:`expand_tabs` is false and :attr:`replace_whitespace` is true, each tab
+ character will be replaced by a single space, which is *not* the same as tab
+ expansion.
+
+
+.. attribute:: TextWrapper.drop_whitespace
+
+ (default: ``True``) If true, whitespace that, after wrapping, happens to end up
+ at the beginning or end of a line is dropped (leading whitespace in the first
+ line is always preserved, though).
+
+ .. versionadded:: 2.6
+ Whitespace was always dropped in earlier versions.
+
+
+.. attribute:: TextWrapper.initial_indent
+
+ (default: ``''``) String that will be prepended to the first line of wrapped
+ output. Counts towards the length of the first line.
+
+
+.. attribute:: TextWrapper.subsequent_indent
+
+ (default: ``''``) String that will be prepended to all lines of wrapped output
+ except the first. Counts towards the length of each line except the first.
+
+
+.. attribute:: TextWrapper.fix_sentence_endings
+
+ (default: ``False``) If true, :class:`TextWrapper` attempts to detect sentence
+ endings and ensure that sentences are always separated by exactly two spaces.
+ This is generally desired for text in a monospaced font. However, the sentence
+ detection algorithm is imperfect: it assumes that a sentence ending consists of
+ a lowercase letter followed by one of ``'.'``, ``'!'``, or ``'?'``, possibly
+ followed by one of ``'"'`` or ``"'"``, followed by a space. One problem with
+ this is algorithm is that it is unable to detect the difference between "Dr." in
+ ::
+
+ [...] Dr. Frankenstein's monster [...]
+
+ and "Spot." in ::
+
+ [...] See Spot. See Spot run [...]
+
+ :attr:`fix_sentence_endings` is false by default.
+
+ Since the sentence detection algorithm relies on ``string.lowercase`` for the
+ definition of "lowercase letter," and a convention of using two spaces after
+ a period to separate sentences on the same line, it is specific to
+ English-language texts.
+
+
+.. attribute:: TextWrapper.break_long_words
+
+ (default: ``True``) If true, then words longer than :attr:`width` will be broken
+ in order to ensure that no lines are longer than :attr:`width`. If it is false,
+ long words will not be broken, and some lines may be longer than :attr:`width`.
+ (Long words will be put on a line by themselves, in order to minimize the amount
+ by which :attr:`width` is exceeded.)
+
+:class:`TextWrapper` also provides two public methods, analogous to the
+module-level convenience functions:
+
+
+.. method:: TextWrapper.wrap(text)
+
+ Wraps the single paragraph in *text* (a string) so every line is at most
+ :attr:`width` characters long. All wrapping options are taken from instance
+ attributes of the :class:`TextWrapper` instance. Returns a list of output lines,
+ without final newlines.
+
+
+.. method:: TextWrapper.fill(text)
+
+ Wraps the single paragraph in *text*, and returns a single string containing the
+ wrapped paragraph.
+
diff --git a/Doc/library/thread.rst b/Doc/library/thread.rst
new file mode 100644
index 0000000000..c9be598c8e
--- /dev/null
+++ b/Doc/library/thread.rst
@@ -0,0 +1,171 @@
+
+:mod:`thread` --- Multiple threads of control
+=============================================
+
+.. module:: thread
+ :synopsis: Create multiple threads of control within one interpreter.
+
+
+.. index::
+ single: light-weight processes
+ single: processes, light-weight
+ single: binary semaphores
+ single: semaphores, binary
+
+This module provides low-level primitives for working with multiple threads
+(a.k.a. :dfn:`light-weight processes` or :dfn:`tasks`) --- multiple threads of
+control sharing their global data space. For synchronization, simple locks
+(a.k.a. :dfn:`mutexes` or :dfn:`binary semaphores`) are provided.
+
+.. index::
+ single: pthreads
+ pair: threads; POSIX
+
+The module is optional. It is supported on Windows, Linux, SGI IRIX, Solaris
+2.x, as well as on systems that have a POSIX thread (a.k.a. "pthread")
+implementation. For systems lacking the :mod:`thread` module, the
+:mod:`dummy_thread` module is available. It duplicates this module's interface
+and can be used as a drop-in replacement.
+
+It defines the following constant and functions:
+
+
+.. exception:: error
+
+ Raised on thread-specific errors.
+
+
+.. data:: LockType
+
+ This is the type of lock objects.
+
+
+.. function:: start_new_thread(function, args[, kwargs])
+
+ Start a new thread and return its identifier. The thread executes the function
+ *function* with the argument list *args* (which must be a tuple). The optional
+ *kwargs* argument specifies a dictionary of keyword arguments. When the function
+ returns, the thread silently exits. When the function terminates with an
+ unhandled exception, a stack trace is printed and then the thread exits (but
+ other threads continue to run).
+
+
+.. function:: interrupt_main()
+
+ Raise a :exc:`KeyboardInterrupt` exception in the main thread. A subthread can
+ use this function to interrupt the main thread.
+
+ .. versionadded:: 2.3
+
+
+.. function:: exit()
+
+ Raise the :exc:`SystemExit` exception. When not caught, this will cause the
+ thread to exit silently.
+
+.. % \begin{funcdesc}{exit_prog}{status}
+.. % Exit all threads and report the value of the integer argument
+.. % \var{status} as the exit status of the entire program.
+.. % \strong{Caveat:} code in pending \keyword{finally} clauses, in this thread
+.. % or in other threads, is not executed.
+.. % \end{funcdesc}
+
+
+.. function:: allocate_lock()
+
+ Return a new lock object. Methods of locks are described below. The lock is
+ initially unlocked.
+
+
+.. function:: get_ident()
+
+ Return the 'thread identifier' of the current thread. This is a nonzero
+ integer. Its value has no direct meaning; it is intended as a magic cookie to
+ be used e.g. to index a dictionary of thread-specific data. Thread identifiers
+ may be recycled when a thread exits and another thread is created.
+
+
+.. function:: stack_size([size])
+
+ Return the thread stack size used when creating new threads. The optional
+ *size* argument specifies the stack size to be used for subsequently created
+ threads, and must be 0 (use platform or configured default) or a positive
+ integer value of at least 32,768 (32kB). If changing the thread stack size is
+ unsupported, a :exc:`ThreadError` is raised. If the specified stack size is
+ invalid, a :exc:`ValueError` is raised and the stack size is unmodified. 32kB
+ is currently the minimum supported stack size value to guarantee sufficient
+ stack space for the interpreter itself. Note that some platforms may have
+ particular restrictions on values for the stack size, such as requiring a
+ minimum stack size > 32kB or requiring allocation in multiples of the system
+ memory page size - platform documentation should be referred to for more
+ information (4kB pages are common; using multiples of 4096 for the stack size is
+ the suggested approach in the absence of more specific information).
+ Availability: Windows, systems with POSIX threads.
+
+ .. versionadded:: 2.5
+
+Lock objects have the following methods:
+
+
+.. method:: lock.acquire([waitflag])
+
+ Without the optional argument, this method acquires the lock unconditionally, if
+ necessary waiting until it is released by another thread (only one thread at a
+ time can acquire a lock --- that's their reason for existence). If the integer
+ *waitflag* argument is present, the action depends on its value: if it is zero,
+ the lock is only acquired if it can be acquired immediately without waiting,
+ while if it is nonzero, the lock is acquired unconditionally as before. The
+ return value is ``True`` if the lock is acquired successfully, ``False`` if not.
+
+
+.. method:: lock.release()
+
+ Releases the lock. The lock must have been acquired earlier, but not
+ necessarily by the same thread.
+
+
+.. method:: lock.locked()
+
+ Return the status of the lock: ``True`` if it has been acquired by some thread,
+ ``False`` if not.
+
+In addition to these methods, lock objects can also be used via the
+:keyword:`with` statement, e.g.::
+
+ from __future__ import with_statement
+ import thread
+
+ a_lock = thread.allocate_lock()
+
+ with a_lock:
+ print "a_lock is locked while this executes"
+
+**Caveats:**
+
+ .. index:: module: signal
+
+* Threads interact strangely with interrupts: the :exc:`KeyboardInterrupt`
+ exception will be received by an arbitrary thread. (When the :mod:`signal`
+ module is available, interrupts always go to the main thread.)
+
+* Calling :func:`sys.exit` or raising the :exc:`SystemExit` exception is
+ equivalent to calling :func:`exit`.
+
+* Not all built-in functions that may block waiting for I/O allow other threads
+ to run. (The most popular ones (:func:`time.sleep`, :meth:`file.read`,
+ :func:`select.select`) work as expected.)
+
+* It is not possible to interrupt the :meth:`acquire` method on a lock --- the
+ :exc:`KeyboardInterrupt` exception will happen after the lock has been acquired.
+
+ .. index:: pair: threads; IRIX
+
+* When the main thread exits, it is system defined whether the other threads
+ survive. On SGI IRIX using the native thread implementation, they survive. On
+ most other systems, they are killed without executing :keyword:`try` ...
+ :keyword:`finally` clauses or executing object destructors.
+
+* When the main thread exits, it does not do any of its usual cleanup (except
+ that :keyword:`try` ... :keyword:`finally` clauses are honored), and the
+ standard I/O files are not flushed.
+
diff --git a/Doc/library/threading.rst b/Doc/library/threading.rst
new file mode 100644
index 0000000000..92ce02a39c
--- /dev/null
+++ b/Doc/library/threading.rst
@@ -0,0 +1,732 @@
+
+:mod:`threading` --- Higher-level threading interface
+=====================================================
+
+.. module:: threading
+ :synopsis: Higher-level threading interface.
+
+
+This module constructs higher-level threading interfaces on top of the lower
+level :mod:`thread` module.
+
+The :mod:`dummy_threading` module is provided for situations where
+:mod:`threading` cannot be used because :mod:`thread` is missing.
+
+This module defines the following functions and objects:
+
+
+.. function:: activeCount()
+
+ Return the number of :class:`Thread` objects currently alive. The returned
+ count is equal to the length of the list returned by :func:`enumerate`.
+
+
+.. function:: Condition()
+ :noindex:
+
+ A factory function that returns a new condition variable object. A condition
+ variable allows one or more threads to wait until they are notified by another
+ thread.
+
+
+.. function:: currentThread()
+
+ Return the current :class:`Thread` object, corresponding to the caller's thread
+ of control. If the caller's thread of control was not created through the
+ :mod:`threading` module, a dummy thread object with limited functionality is
+ returned.
+
+
+.. function:: enumerate()
+
+ Return a list of all :class:`Thread` objects currently alive. The list includes
+ daemonic threads, dummy thread objects created by :func:`currentThread`, and the
+ main thread. It excludes terminated threads and threads that have not yet been
+ started.
+
+
+.. function:: Event()
+ :noindex:
+
+ A factory function that returns a new event object. An event manages a flag
+ that can be set to true with the :meth:`set` method and reset to false with the
+ :meth:`clear` method. The :meth:`wait` method blocks until the flag is true.
+
+
+.. class:: local
+
+ A class that represents thread-local data. Thread-local data are data whose
+ values are thread specific. To manage thread-local data, just create an
+ instance of :class:`local` (or a subclass) and store attributes on it::
+
+ mydata = threading.local()
+ mydata.x = 1
+
+ The instance's values will be different for separate threads.
+
+ For more details and extensive examples, see the documentation string of the
+ :mod:`_threading_local` module.
+
+ .. versionadded:: 2.4
+
+
+.. function:: Lock()
+
+ A factory function that returns a new primitive lock object. Once a thread has
+ acquired it, subsequent attempts to acquire it block, until it is released; any
+ thread may release it.
+
+
+.. function:: RLock()
+
+ A factory function that returns a new reentrant lock object. A reentrant lock
+ must be released by the thread that acquired it. Once a thread has acquired a
+ reentrant lock, the same thread may acquire it again without blocking; the
+ thread must release it once for each time it has acquired it.
+
+
+.. function:: Semaphore([value])
+ :noindex:
+
+ A factory function that returns a new semaphore object. A semaphore manages a
+ counter representing the number of :meth:`release` calls minus the number of
+ :meth:`acquire` calls, plus an initial value. The :meth:`acquire` method blocks
+ if necessary until it can return without making the counter negative. If not
+ given, *value* defaults to 1.
+
+
+.. function:: BoundedSemaphore([value])
+
+ A factory function that returns a new bounded semaphore object. A bounded
+ semaphore checks to make sure its current value doesn't exceed its initial
+ value. If it does, :exc:`ValueError` is raised. In most situations semaphores
+ are used to guard resources with limited capacity. If the semaphore is released
+ too many times it's a sign of a bug. If not given, *value* defaults to 1.
+
+
+.. class:: Thread
+
+ A class that represents a thread of control. This class can be safely
+ subclassed in a limited fashion.
+
+
+.. class:: Timer
+
+ A thread that executes a function after a specified interval has passed.
+
+
+.. function:: settrace(func)
+
+ .. index:: single: trace function
+
+ Set a trace function for all threads started from the :mod:`threading` module.
+ The *func* will be passed to :func:`sys.settrace` for each thread, before its
+ :meth:`run` method is called.
+
+ .. versionadded:: 2.3
+
+
+.. function:: setprofile(func)
+
+ .. index:: single: profile function
+
+ Set a profile function for all threads started from the :mod:`threading` module.
+ The *func* will be passed to :func:`sys.setprofile` for each thread, before its
+ :meth:`run` method is called.
+
+ .. versionadded:: 2.3
+
+
+.. function:: stack_size([size])
+
+ Return the thread stack size used when creating new threads. The optional
+ *size* argument specifies the stack size to be used for subsequently created
+ threads, and must be 0 (use platform or configured default) or a positive
+ integer value of at least 32,768 (32kB). If changing the thread stack size is
+ unsupported, a :exc:`ThreadError` is raised. If the specified stack size is
+ invalid, a :exc:`ValueError` is raised and the stack size is unmodified. 32kB
+ is currently the minimum supported stack size value to guarantee sufficient
+ stack space for the interpreter itself. Note that some platforms may have
+ particular restrictions on values for the stack size, such as requiring a
+ minimum stack size > 32kB or requiring allocation in multiples of the system
+ memory page size - platform documentation should be referred to for more
+ information (4kB pages are common; using multiples of 4096 for the stack size is
+ the suggested approach in the absence of more specific information).
+ Availability: Windows, systems with POSIX threads.
+
+ .. versionadded:: 2.5
+
+Detailed interfaces for the objects are documented below.
+
+The design of this module is loosely based on Java's threading model. However,
+where Java makes locks and condition variables basic behavior of every object,
+they are separate objects in Python. Python's :class:`Thread` class supports a
+subset of the behavior of Java's Thread class; currently, there are no
+priorities, no thread groups, and threads cannot be destroyed, stopped,
+suspended, resumed, or interrupted. The static methods of Java's Thread class,
+when implemented, are mapped to module-level functions.
+
+All of the methods described below are executed atomically.
+
+
+.. _lock-objects:
+
+Lock Objects
+------------
+
+A primitive lock is a synchronization primitive that is not owned by a
+particular thread when locked. In Python, it is currently the lowest level
+synchronization primitive available, implemented directly by the :mod:`thread`
+extension module.
+
+A primitive lock is in one of two states, "locked" or "unlocked". It is created
+in the unlocked state. It has two basic methods, :meth:`acquire` and
+:meth:`release`. When the state is unlocked, :meth:`acquire` changes the state
+to locked and returns immediately. When the state is locked, :meth:`acquire`
+blocks until a call to :meth:`release` in another thread changes it to unlocked,
+then the :meth:`acquire` call resets it to locked and returns. The
+:meth:`release` method should only be called in the locked state; it changes the
+state to unlocked and returns immediately. If an attempt is made to release an
+unlocked lock, a :exc:`RuntimeError` will be raised.
+
+When more than one thread is blocked in :meth:`acquire` waiting for the state to
+turn to unlocked, only one thread proceeds when a :meth:`release` call resets
+the state to unlocked; which one of the waiting threads proceeds is not defined,
+and may vary across implementations.
+
+All methods are executed atomically.
+
+
+.. method:: Lock.acquire([blocking=1])
+
+ Acquire a lock, blocking or non-blocking.
+
+ When invoked without arguments, block until the lock is unlocked, then set it to
+ locked, and return true.
+
+ When invoked with the *blocking* argument set to true, do the same thing as when
+ called without arguments, and return true.
+
+ When invoked with the *blocking* argument set to false, do not block. If a call
+ without an argument would block, return false immediately; otherwise, do the
+ same thing as when called without arguments, and return true.
+
+
+.. method:: Lock.release()
+
+ Release a lock.
+
+ When the lock is locked, reset it to unlocked, and return. If any other threads
+ are blocked waiting for the lock to become unlocked, allow exactly one of them
+ to proceed.
+
+ Do not call this method when the lock is unlocked.
+
+ There is no return value.
+
+
+.. _rlock-objects:
+
+RLock Objects
+-------------
+
+A reentrant lock is a synchronization primitive that may be acquired multiple
+times by the same thread. Internally, it uses the concepts of "owning thread"
+and "recursion level" in addition to the locked/unlocked state used by primitive
+locks. In the locked state, some thread owns the lock; in the unlocked state,
+no thread owns it.
+
+To lock the lock, a thread calls its :meth:`acquire` method; this returns once
+the thread owns the lock. To unlock the lock, a thread calls its
+:meth:`release` method. :meth:`acquire`/:meth:`release` call pairs may be
+nested; only the final :meth:`release` (the :meth:`release` of the outermost
+pair) resets the lock to unlocked and allows another thread blocked in
+:meth:`acquire` to proceed.
+
+
+.. method:: RLock.acquire([blocking=1])
+
+ Acquire a lock, blocking or non-blocking.
+
+ When invoked without arguments: if this thread already owns the lock, increment
+ the recursion level by one, and return immediately. Otherwise, if another
+ thread owns the lock, block until the lock is unlocked. Once the lock is
+ unlocked (not owned by any thread), then grab ownership, set the recursion level
+ to one, and return. If more than one thread is blocked waiting until the lock
+ is unlocked, only one at a time will be able to grab ownership of the lock.
+ There is no return value in this case.
+
+ When invoked with the *blocking* argument set to true, do the same thing as when
+ called without arguments, and return true.
+
+ When invoked with the *blocking* argument set to false, do not block. If a call
+ without an argument would block, return false immediately; otherwise, do the
+ same thing as when called without arguments, and return true.
+
+
+.. method:: RLock.release()
+
+ Release a lock, decrementing the recursion level. If after the decrement it is
+ zero, reset the lock to unlocked (not owned by any thread), and if any other
+ threads are blocked waiting for the lock to become unlocked, allow exactly one
+ of them to proceed. If after the decrement the recursion level is still
+ nonzero, the lock remains locked and owned by the calling thread.
+
+ Only call this method when the calling thread owns the lock. A
+ :exc:`RuntimeError` is raised if this method is called when the lock is
+ unlocked.
+
+ There is no return value.
+
+
+.. _condition-objects:
+
+Condition Objects
+-----------------
+
+A condition variable is always associated with some kind of lock; this can be
+passed in or one will be created by default. (Passing one in is useful when
+several condition variables must share the same lock.)
+
+A condition variable has :meth:`acquire` and :meth:`release` methods that call
+the corresponding methods of the associated lock. It also has a :meth:`wait`
+method, and :meth:`notify` and :meth:`notifyAll` methods. These three must only
+be called when the calling thread has acquired the lock, otherwise a
+:exc:`RuntimeError` is raised.
+
+The :meth:`wait` method releases the lock, and then blocks until it is awakened
+by a :meth:`notify` or :meth:`notifyAll` call for the same condition variable in
+another thread. Once awakened, it re-acquires the lock and returns. It is also
+possible to specify a timeout.
+
+The :meth:`notify` method wakes up one of the threads waiting for the condition
+variable, if any are waiting. The :meth:`notifyAll` method wakes up all threads
+waiting for the condition variable.
+
+Note: the :meth:`notify` and :meth:`notifyAll` methods don't release the lock;
+this means that the thread or threads awakened will not return from their
+:meth:`wait` call immediately, but only when the thread that called
+:meth:`notify` or :meth:`notifyAll` finally relinquishes ownership of the lock.
+
+Tip: the typical programming style using condition variables uses the lock to
+synchronize access to some shared state; threads that are interested in a
+particular change of state call :meth:`wait` repeatedly until they see the
+desired state, while threads that modify the state call :meth:`notify` or
+:meth:`notifyAll` when they change the state in such a way that it could
+possibly be a desired state for one of the waiters. For example, the following
+code is a generic producer-consumer situation with unlimited buffer capacity::
+
+ # Consume one item
+ cv.acquire()
+ while not an_item_is_available():
+ cv.wait()
+ get_an_available_item()
+ cv.release()
+
+ # Produce one item
+ cv.acquire()
+ make_an_item_available()
+ cv.notify()
+ cv.release()
+
+To choose between :meth:`notify` and :meth:`notifyAll`, consider whether one
+state change can be interesting for only one or several waiting threads. E.g.
+in a typical producer-consumer situation, adding one item to the buffer only
+needs to wake up one consumer thread.
+
+
+.. class:: Condition([lock])
+
+ If the *lock* argument is given and not ``None``, it must be a :class:`Lock` or
+ :class:`RLock` object, and it is used as the underlying lock. Otherwise, a new
+ :class:`RLock` object is created and used as the underlying lock.
+
+
+.. method:: Condition.acquire(*args)
+
+ Acquire the underlying lock. This method calls the corresponding method on the
+ underlying lock; the return value is whatever that method returns.
+
+
+.. method:: Condition.release()
+
+ Release the underlying lock. This method calls the corresponding method on the
+ underlying lock; there is no return value.
+
+
+.. method:: Condition.wait([timeout])
+
+ Wait until notified or until a timeout occurs. If the calling thread has not
+ acquired the lock when this method is called, a :exc:`RuntimeError` is raised.
+
+ This method releases the underlying lock, and then blocks until it is awakened
+ by a :meth:`notify` or :meth:`notifyAll` call for the same condition variable in
+ another thread, or until the optional timeout occurs. Once awakened or timed
+ out, it re-acquires the lock and returns.
+
+ When the *timeout* argument is present and not ``None``, it should be a floating
+ point number specifying a timeout for the operation in seconds (or fractions
+ thereof).
+
+ When the underlying lock is an :class:`RLock`, it is not released using its
+ :meth:`release` method, since this may not actually unlock the lock when it was
+ acquired multiple times recursively. Instead, an internal interface of the
+ :class:`RLock` class is used, which really unlocks it even when it has been
+ recursively acquired several times. Another internal interface is then used to
+ restore the recursion level when the lock is reacquired.
+
+
+.. method:: Condition.notify()
+
+ Wake up a thread waiting on this condition, if any. Wait until notified or until
+ a timeout occurs. If the calling thread has not acquired the lock when this
+ method is called, a :exc:`RuntimeError` is raised.
+
+ This method wakes up one of the threads waiting for the condition variable, if
+ any are waiting; it is a no-op if no threads are waiting.
+
+ The current implementation wakes up exactly one thread, if any are waiting.
+ However, it's not safe to rely on this behavior. A future, optimized
+ implementation may occasionally wake up more than one thread.
+
+ Note: the awakened thread does not actually return from its :meth:`wait` call
+ until it can reacquire the lock. Since :meth:`notify` does not release the
+ lock, its caller should.
+
+
+.. method:: Condition.notifyAll()
+
+ Wake up all threads waiting on this condition. This method acts like
+ :meth:`notify`, but wakes up all waiting threads instead of one. If the calling
+ thread has not acquired the lock when this method is called, a
+ :exc:`RuntimeError` is raised.
+
+
+.. _semaphore-objects:
+
+Semaphore Objects
+-----------------
+
+This is one of the oldest synchronization primitives in the history of computer
+science, invented by the early Dutch computer scientist Edsger W. Dijkstra (he
+used :meth:`P` and :meth:`V` instead of :meth:`acquire` and :meth:`release`).
+
+A semaphore manages an internal counter which is decremented by each
+:meth:`acquire` call and incremented by each :meth:`release` call. The counter
+can never go below zero; when :meth:`acquire` finds that it is zero, it blocks,
+waiting until some other thread calls :meth:`release`.
+
+
+.. class:: Semaphore([value])
+
+ The optional argument gives the initial *value* for the internal counter; it
+ defaults to ``1``. If the *value* given is less than 0, :exc:`ValueError` is
+ raised.
+
+
+.. method:: Semaphore.acquire([blocking])
+
+ Acquire a semaphore.
+
+ When invoked without arguments: if the internal counter is larger than zero on
+ entry, decrement it by one and return immediately. If it is zero on entry,
+ block, waiting until some other thread has called :meth:`release` to make it
+ larger than zero. This is done with proper interlocking so that if multiple
+ :meth:`acquire` calls are blocked, :meth:`release` will wake exactly one of them
+ up. The implementation may pick one at random, so the order in which blocked
+ threads are awakened should not be relied on. There is no return value in this
+ case.
+
+ When invoked with *blocking* set to true, do the same thing as when called
+ without arguments, and return true.
+
+ When invoked with *blocking* set to false, do not block. If a call without an
+ argument would block, return false immediately; otherwise, do the same thing as
+ when called without arguments, and return true.
+
+
+.. method:: Semaphore.release()
+
+ Release a semaphore, incrementing the internal counter by one. When it was zero
+ on entry and another thread is waiting for it to become larger than zero again,
+ wake up that thread.
+
+
+.. _semaphore-examples:
+
+:class:`Semaphore` Example
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Semaphores are often used to guard resources with limited capacity, for example,
+a database server. In any situation where the size of the resource size is
+fixed, you should use a bounded semaphore. Before spawning any worker threads,
+your main thread would initialize the semaphore::
+
+ maxconnections = 5
+ ...
+ pool_sema = BoundedSemaphore(value=maxconnections)
+
+Once spawned, worker threads call the semaphore's acquire and release methods
+when they need to connect to the server::
+
+ pool_sema.acquire()
+ conn = connectdb()
+ ... use connection ...
+ conn.close()
+ pool_sema.release()
+
+The use of a bounded semaphore reduces the chance that a programming error which
+causes the semaphore to be released more than it's acquired will go undetected.
+
+
+.. _event-objects:
+
+Event Objects
+-------------
+
+This is one of the simplest mechanisms for communication between threads: one
+thread signals an event and other threads wait for it.
+
+An event object manages an internal flag that can be set to true with the
+:meth:`set` method and reset to false with the :meth:`clear` method. The
+:meth:`wait` method blocks until the flag is true.
+
+
+.. class:: Event()
+
+ The internal flag is initially false.
+
+
+.. method:: Event.isSet()
+
+ Return true if and only if the internal flag is true.
+
+
+.. method:: Event.set()
+
+ Set the internal flag to true. All threads waiting for it to become true are
+ awakened. Threads that call :meth:`wait` once the flag is true will not block at
+ all.
+
+
+.. method:: Event.clear()
+
+ Reset the internal flag to false. Subsequently, threads calling :meth:`wait`
+ will block until :meth:`set` is called to set the internal flag to true again.
+
+
+.. method:: Event.wait([timeout])
+
+ Block until the internal flag is true. If the internal flag is true on entry,
+ return immediately. Otherwise, block until another thread calls :meth:`set` to
+ set the flag to true, or until the optional timeout occurs.
+
+ When the timeout argument is present and not ``None``, it should be a floating
+ point number specifying a timeout for the operation in seconds (or fractions
+ thereof).
+
+
+.. _thread-objects:
+
+Thread Objects
+--------------
+
+This class represents an activity that is run in a separate thread of control.
+There are two ways to specify the activity: by passing a callable object to the
+constructor, or by overriding the :meth:`run` method in a subclass. No other
+methods (except for the constructor) should be overridden in a subclass. In
+other words, *only* override the :meth:`__init__` and :meth:`run` methods of
+this class.
+
+Once a thread object is created, its activity must be started by calling the
+thread's :meth:`start` method. This invokes the :meth:`run` method in a
+separate thread of control.
+
+Once the thread's activity is started, the thread is considered 'alive'. It
+stops being alive when its :meth:`run` method terminates -- either normally, or
+by raising an unhandled exception. The :meth:`isAlive` method tests whether the
+thread is alive.
+
+Other threads can call a thread's :meth:`join` method. This blocks the calling
+thread until the thread whose :meth:`join` method is called is terminated.
+
+A thread has a name. The name can be passed to the constructor, set with the
+:meth:`setName` method, and retrieved with the :meth:`getName` method.
+
+A thread can be flagged as a "daemon thread". The significance of this flag is
+that the entire Python program exits when only daemon threads are left. The
+initial value is inherited from the creating thread. The flag can be set with
+the :meth:`setDaemon` method and retrieved with the :meth:`isDaemon` method.
+
+There is a "main thread" object; this corresponds to the initial thread of
+control in the Python program. It is not a daemon thread.
+
+There is the possibility that "dummy thread objects" are created. These are
+thread objects corresponding to "alien threads", which are threads of control
+started outside the threading module, such as directly from C code. Dummy
+thread objects have limited functionality; they are always considered alive and
+daemonic, and cannot be :meth:`join`\ ed. They are never deleted, since it is
+impossible to detect the termination of alien threads.
+
+
+.. class:: Thread(group=None, target=None, name=None, args=(), kwargs={})
+
+ This constructor should always be called with keyword arguments. Arguments are:
+
+ *group* should be ``None``; reserved for future extension when a
+ :class:`ThreadGroup` class is implemented.
+
+ *target* is the callable object to be invoked by the :meth:`run` method.
+ Defaults to ``None``, meaning nothing is called.
+
+ *name* is the thread name. By default, a unique name is constructed of the form
+ "Thread-*N*" where *N* is a small decimal number.
+
+ *args* is the argument tuple for the target invocation. Defaults to ``()``.
+
+ *kwargs* is a dictionary of keyword arguments for the target invocation.
+ Defaults to ``{}``.
+
+ If the subclass overrides the constructor, it must make sure to invoke the base
+ class constructor (``Thread.__init__()``) before doing anything else to the
+ thread.
+
+
+.. method:: Thread.start()
+
+ Start the thread's activity.
+
+ It must be called at most once per thread object. It arranges for the object's
+ :meth:`run` method to be invoked in a separate thread of control.
+
+ This method will raise a :exc:`RuntimeException` if called more than once on the
+ same thread object.
+
+
+.. method:: Thread.run()
+
+ Method representing the thread's activity.
+
+ You may override this method in a subclass. The standard :meth:`run` method
+ invokes the callable object passed to the object's constructor as the *target*
+ argument, if any, with sequential and keyword arguments taken from the *args*
+ and *kwargs* arguments, respectively.
+
+
+.. method:: Thread.join([timeout])
+
+ Wait until the thread terminates. This blocks the calling thread until the
+ thread whose :meth:`join` method is called terminates -- either normally or
+ through an unhandled exception -- or until the optional timeout occurs.
+
+ When the *timeout* argument is present and not ``None``, it should be a floating
+ point number specifying a timeout for the operation in seconds (or fractions
+ thereof). As :meth:`join` always returns ``None``, you must call
+ :meth:`isAlive` to decide whether a timeout happened.
+
+ When the *timeout* argument is not present or ``None``, the operation will block
+ until the thread terminates.
+
+ A thread can be :meth:`join`\ ed many times.
+
+ :meth:`join` may throw a :exc:`RuntimeError`, if an attempt is made to join the
+ current thread as that would cause a deadlock. It is also an error to
+ :meth:`join` a thread before it has been started and attempts to do so raises
+ same exception.
+
+
+.. method:: Thread.getName()
+
+ Return the thread's name.
+
+
+.. method:: Thread.setName(name)
+
+ Set the thread's name.
+
+ The name is a string used for identification purposes only. It has no semantics.
+ Multiple threads may be given the same name. The initial name is set by the
+ constructor.
+
+
+.. method:: Thread.isAlive()
+
+ Return whether the thread is alive.
+
+ Roughly, a thread is alive from the moment the :meth:`start` method returns
+ until its :meth:`run` method terminates. The module function :func:`enumerate`
+ returns a list of all alive threads.
+
+
+.. method:: Thread.isDaemon()
+
+ Return the thread's daemon flag.
+
+
+.. method:: Thread.setDaemon(daemonic)
+
+ Set the thread's daemon flag to the Boolean value *daemonic*. This must be
+ called before :meth:`start` is called, otherwise :exc:`RuntimeError` is raised.
+
+ The initial value is inherited from the creating thread.
+
+ The entire Python program exits when no alive non-daemon threads are left.
+
+
+.. _timer-objects:
+
+Timer Objects
+-------------
+
+This class represents an action that should be run only after a certain amount
+of time has passed --- a timer. :class:`Timer` is a subclass of :class:`Thread`
+and as such also functions as an example of creating custom threads.
+
+Timers are started, as with threads, by calling their :meth:`start` method. The
+timer can be stopped (before its action has begun) by calling the :meth:`cancel`
+method. The interval the timer will wait before executing its action may not be
+exactly the same as the interval specified by the user.
+
+For example::
+
+ def hello():
+ print "hello, world"
+
+ t = Timer(30.0, hello)
+ t.start() # after 30 seconds, "hello, world" will be printed
+
+
+.. class:: Timer(interval, function, args=[], kwargs={})
+
+ Create a timer that will run *function* with arguments *args* and keyword
+ arguments *kwargs*, after *interval* seconds have passed.
+
+
+.. method:: Timer.cancel()
+
+ Stop the timer, and cancel the execution of the timer's action. This will only
+ work if the timer is still in its waiting stage.
+
+
+.. _with-locks:
+
+Using locks, conditions, and semaphores in the :keyword:`with` statement
+------------------------------------------------------------------------
+
+All of the objects provided by this module that have :meth:`acquire` and
+:meth:`release` methods can be used as context managers for a :keyword:`with`
+statement. The :meth:`acquire` method will be called when the block is entered,
+and :meth:`release` will be called when the block is exited.
+
+Currently, :class:`Lock`, :class:`RLock`, :class:`Condition`,
+:class:`Semaphore`, and :class:`BoundedSemaphore` objects may be used as
+:keyword:`with` statement context managers. For example::
+
+ from __future__ import with_statement
+ import threading
+
+ some_rlock = threading.RLock()
+
+ with some_rlock:
+ print "some_rlock is locked while this executes"
+
diff --git a/Doc/library/time.rst b/Doc/library/time.rst
new file mode 100644
index 0000000000..04c8f66f0b
--- /dev/null
+++ b/Doc/library/time.rst
@@ -0,0 +1,540 @@
+
+:mod:`time` --- Time access and conversions
+===========================================
+
+.. module:: time
+ :synopsis: Time access and conversions.
+
+
+This module provides various time-related functions. For related
+functionality, see also the :mod:`datetime` and :mod:`calendar` modules.
+
+Although this module is always available,
+not all functions are available on all platforms. Most of the functions
+defined in this module call platform C library functions with the same name. It
+may sometimes be helpful to consult the platform documentation, because the
+semantics of these functions varies among platforms.
+
+An explanation of some terminology and conventions is in order.
+
+ .. index:: single: epoch
+
+* The :dfn:`epoch` is the point where the time starts. On January 1st of that
+ year, at 0 hours, the "time since the epoch" is zero. For Unix, the epoch is
+ 1970. To find out what the epoch is, look at ``gmtime(0)``.
+
+ .. index:: single: Year 2038
+
+* The functions in this module do not handle dates and times before the epoch or
+ far in the future. The cut-off point in the future is determined by the C
+ library; for Unix, it is typically in 2038.
+
+ .. index::
+ single: Year 2000
+ single: Y2K
+
+* **Year 2000 (Y2K) issues**: Python depends on the platform's C library, which
+ generally doesn't have year 2000 issues, since all dates and times are
+ represented internally as seconds since the epoch. Functions accepting a
+ :class:`struct_time` (see below) generally require a 4-digit year. For backward
+ compatibility, 2-digit years are supported if the module variable
+ ``accept2dyear`` is a non-zero integer; this variable is initialized to ``1``
+ unless the environment variable :envvar:`PYTHONY2K` is set to a non-empty
+ string, in which case it is initialized to ``0``. Thus, you can set
+ :envvar:`PYTHONY2K` to a non-empty string in the environment to require 4-digit
+ years for all year input. When 2-digit years are accepted, they are converted
+ according to the POSIX or X/Open standard: values 69-99 are mapped to 1969-1999,
+ and values 0--68 are mapped to 2000--2068. Values 100--1899 are always illegal.
+ Note that this is new as of Python 1.5.2(a2); earlier versions, up to Python
+ 1.5.1 and 1.5.2a1, would add 1900 to year values below 1900.
+
+ .. index::
+ single: UTC
+ single: Coordinated Universal Time
+ single: Greenwich Mean Time
+
+* UTC is Coordinated Universal Time (formerly known as Greenwich Mean Time, or
+ GMT). The acronym UTC is not a mistake but a compromise between English and
+ French.
+
+ .. index:: single: Daylight Saving Time
+
+* DST is Daylight Saving Time, an adjustment of the timezone by (usually) one
+ hour during part of the year. DST rules are magic (determined by local law) and
+ can change from year to year. The C library has a table containing the local
+ rules (often it is read from a system file for flexibility) and is the only
+ source of True Wisdom in this respect.
+
+* The precision of the various real-time functions may be less than suggested by
+ the units in which their value or argument is expressed. E.g. on most Unix
+ systems, the clock "ticks" only 50 or 100 times a second, and on the Mac, times
+ are only accurate to whole seconds.
+
+* On the other hand, the precision of :func:`time` and :func:`sleep` is better
+ than their Unix equivalents: times are expressed as floating point numbers,
+ :func:`time` returns the most accurate time available (using Unix
+ :cfunc:`gettimeofday` where available), and :func:`sleep` will accept a time
+ with a nonzero fraction (Unix :cfunc:`select` is used to implement this, where
+ available).
+
+* The time value as returned by :func:`gmtime`, :func:`localtime`, and
+ :func:`strptime`, and accepted by :func:`asctime`, :func:`mktime` and
+ :func:`strftime`, is a sequence of 9 integers. The return values of
+ :func:`gmtime`, :func:`localtime`, and :func:`strptime` also offer attribute
+ names for individual fields.
+
+ +-------+------------------+------------------------------+
+ | Index | Attribute | Values |
+ +=======+==================+==============================+
+ | 0 | :attr:`tm_year` | (for example, 1993) |
+ +-------+------------------+------------------------------+
+ | 1 | :attr:`tm_mon` | range [1,12] |
+ +-------+------------------+------------------------------+
+ | 2 | :attr:`tm_mday` | range [1,31] |
+ +-------+------------------+------------------------------+
+ | 3 | :attr:`tm_hour` | range [0,23] |
+ +-------+------------------+------------------------------+
+ | 4 | :attr:`tm_min` | range [0,59] |
+ +-------+------------------+------------------------------+
+ | 5 | :attr:`tm_sec` | range [0,61]; see **(1)** in |
+ | | | :func:`strftime` description |
+ +-------+------------------+------------------------------+
+ | 6 | :attr:`tm_wday` | range [0,6], Monday is 0 |
+ +-------+------------------+------------------------------+
+ | 7 | :attr:`tm_yday` | range [1,366] |
+ +-------+------------------+------------------------------+
+ | 8 | :attr:`tm_isdst` | 0, 1 or -1; see below |
+ +-------+------------------+------------------------------+
+
+ Note that unlike the C structure, the month value is a range of 1-12, not 0-11.
+ A year value will be handled as described under "Year 2000 (Y2K) issues" above.
+ A ``-1`` argument as the daylight savings flag, passed to :func:`mktime` will
+ usually result in the correct daylight savings state to be filled in.
+
+ When a tuple with an incorrect length is passed to a function expecting a
+ :class:`struct_time`, or having elements of the wrong type, a :exc:`TypeError`
+ is raised.
+
+ .. versionchanged:: 2.2
+ The time value sequence was changed from a tuple to a :class:`struct_time`, with
+ the addition of attribute names for the fields.
+
+The module defines the following functions and data items:
+
+
+.. data:: accept2dyear
+
+ Boolean value indicating whether two-digit year values will be accepted. This
+ is true by default, but will be set to false if the environment variable
+ :envvar:`PYTHONY2K` has been set to a non-empty string. It may also be modified
+ at run time.
+
+
+.. data:: altzone
+
+ The offset of the local DST timezone, in seconds west of UTC, if one is defined.
+ This is negative if the local DST timezone is east of UTC (as in Western Europe,
+ including the UK). Only use this if ``daylight`` is nonzero.
+
+
+.. function:: asctime([t])
+
+ Convert a tuple or :class:`struct_time` representing a time as returned by
+ :func:`gmtime` or :func:`localtime` to a 24-character string of the following
+ form: ``'Sun Jun 20 23:21:05 1993'``. If *t* is not provided, the current time
+ as returned by :func:`localtime` is used. Locale information is not used by
+ :func:`asctime`.
+
+ .. note::
+
+ Unlike the C function of the same name, there is no trailing newline.
+
+ .. versionchanged:: 2.1
+ Allowed *t* to be omitted.
+
+
+.. function:: clock()
+
+ .. index::
+ single: CPU time
+ single: processor time
+ single: benchmarking
+
+ On Unix, return the current processor time as a floating point number expressed
+ in seconds. The precision, and in fact the very definition of the meaning of
+ "processor time", depends on that of the C function of the same name, but in any
+ case, this is the function to use for benchmarking Python or timing algorithms.
+
+ On Windows, this function returns wall-clock seconds elapsed since the first
+ call to this function, as a floating point number, based on the Win32 function
+ :cfunc:`QueryPerformanceCounter`. The resolution is typically better than one
+ microsecond.
+
+
+.. function:: ctime([secs])
+
+ Convert a time expressed in seconds since the epoch to a string representing
+ local time. If *secs* is not provided or :const:`None`, the current time as
+ returned by :func:`time` is used. ``ctime(secs)`` is equivalent to
+ ``asctime(localtime(secs))``. Locale information is not used by :func:`ctime`.
+
+ .. versionchanged:: 2.1
+ Allowed *secs* to be omitted.
+
+ .. versionchanged:: 2.4
+ If *secs* is :const:`None`, the current time is used.
+
+
+.. data:: daylight
+
+ Nonzero if a DST timezone is defined.
+
+
+.. function:: gmtime([secs])
+
+ Convert a time expressed in seconds since the epoch to a :class:`struct_time` in
+ UTC in which the dst flag is always zero. If *secs* is not provided or
+ :const:`None`, the current time as returned by :func:`time` is used. Fractions
+ of a second are ignored. See above for a description of the
+ :class:`struct_time` object. See :func:`calendar.timegm` for the inverse of this
+ function.
+
+ .. versionchanged:: 2.1
+ Allowed *secs* to be omitted.
+
+ .. versionchanged:: 2.4
+ If *secs* is :const:`None`, the current time is used.
+
+
+.. function:: localtime([secs])
+
+ Like :func:`gmtime` but converts to local time. If *secs* is not provided or
+ :const:`None`, the current time as returned by :func:`time` is used. The dst
+ flag is set to ``1`` when DST applies to the given time.
+
+ .. versionchanged:: 2.1
+ Allowed *secs* to be omitted.
+
+ .. versionchanged:: 2.4
+ If *secs* is :const:`None`, the current time is used.
+
+
+.. function:: mktime(t)
+
+ This is the inverse function of :func:`localtime`. Its argument is the
+ :class:`struct_time` or full 9-tuple (since the dst flag is needed; use ``-1``
+ as the dst flag if it is unknown) which expresses the time in *local* time, not
+ UTC. It returns a floating point number, for compatibility with :func:`time`.
+ If the input value cannot be represented as a valid time, either
+ :exc:`OverflowError` or :exc:`ValueError` will be raised (which depends on
+ whether the invalid value is caught by Python or the underlying C libraries).
+ The earliest date for which it can generate a time is platform-dependent.
+
+
+.. function:: sleep(secs)
+
+ Suspend execution for the given number of seconds. The argument may be a
+ floating point number to indicate a more precise sleep time. The actual
+ suspension time may be less than that requested because any caught signal will
+ terminate the :func:`sleep` following execution of that signal's catching
+ routine. Also, the suspension time may be longer than requested by an arbitrary
+ amount because of the scheduling of other activity in the system.
+
+
+.. function:: strftime(format[, t])
+
+ Convert a tuple or :class:`struct_time` representing a time as returned by
+ :func:`gmtime` or :func:`localtime` to a string as specified by the *format*
+ argument. If *t* is not provided, the current time as returned by
+ :func:`localtime` is used. *format* must be a string. :exc:`ValueError` is
+ raised if any field in *t* is outside of the allowed range.
+
+ .. versionchanged:: 2.1
+ Allowed *t* to be omitted.
+
+ .. versionchanged:: 2.4
+ :exc:`ValueError` raised if a field in *t* is out of range.
+
+ .. versionchanged:: 2.5
+ 0 is now a legal argument for any position in the time tuple; if it is normally
+ illegal the value is forced to a correct one..
+
+ The following directives can be embedded in the *format* string. They are shown
+ without the optional field width and precision specification, and are replaced
+ by the indicated characters in the :func:`strftime` result:
+
+ +-----------+--------------------------------+-------+
+ | Directive | Meaning | Notes |
+ +===========+================================+=======+
+ | ``%a`` | Locale's abbreviated weekday | |
+ | | name. | |
+ +-----------+--------------------------------+-------+
+ | ``%A`` | Locale's full weekday name. | |
+ +-----------+--------------------------------+-------+
+ | ``%b`` | Locale's abbreviated month | |
+ | | name. | |
+ +-----------+--------------------------------+-------+
+ | ``%B`` | Locale's full month name. | |
+ +-----------+--------------------------------+-------+
+ | ``%c`` | Locale's appropriate date and | |
+ | | time representation. | |
+ +-----------+--------------------------------+-------+
+ | ``%d`` | Day of the month as a decimal | |
+ | | number [01,31]. | |
+ +-----------+--------------------------------+-------+
+ | ``%H`` | Hour (24-hour clock) as a | |
+ | | decimal number [00,23]. | |
+ +-----------+--------------------------------+-------+
+ | ``%I`` | Hour (12-hour clock) as a | |
+ | | decimal number [01,12]. | |
+ +-----------+--------------------------------+-------+
+ | ``%j`` | Day of the year as a decimal | |
+ | | number [001,366]. | |
+ +-----------+--------------------------------+-------+
+ | ``%m`` | Month as a decimal number | |
+ | | [01,12]. | |
+ +-----------+--------------------------------+-------+
+ | ``%M`` | Minute as a decimal number | |
+ | | [00,59]. | |
+ +-----------+--------------------------------+-------+
+ | ``%p`` | Locale's equivalent of either | \(1) |
+ | | AM or PM. | |
+ +-----------+--------------------------------+-------+
+ | ``%S`` | Second as a decimal number | \(2) |
+ | | [00,61]. | |
+ +-----------+--------------------------------+-------+
+ | ``%U`` | Week number of the year | \(3) |
+ | | (Sunday as the first day of | |
+ | | the week) as a decimal number | |
+ | | [00,53]. All days in a new | |
+ | | year preceding the first | |
+ | | Sunday are considered to be in | |
+ | | week 0. | |
+ +-----------+--------------------------------+-------+
+ | ``%w`` | Weekday as a decimal number | |
+ | | [0(Sunday),6]. | |
+ +-----------+--------------------------------+-------+
+ | ``%W`` | Week number of the year | \(3) |
+ | | (Monday as the first day of | |
+ | | the week) as a decimal number | |
+ | | [00,53]. All days in a new | |
+ | | year preceding the first | |
+ | | Monday are considered to be in | |
+ | | week 0. | |
+ +-----------+--------------------------------+-------+
+ | ``%x`` | Locale's appropriate date | |
+ | | representation. | |
+ +-----------+--------------------------------+-------+
+ | ``%X`` | Locale's appropriate time | |
+ | | representation. | |
+ +-----------+--------------------------------+-------+
+ | ``%y`` | Year without century as a | |
+ | | decimal number [00,99]. | |
+ +-----------+--------------------------------+-------+
+ | ``%Y`` | Year with century as a decimal | |
+ | | number. | |
+ +-----------+--------------------------------+-------+
+ | ``%Z`` | Time zone name (no characters | |
+ | | if no time zone exists). | |
+ +-----------+--------------------------------+-------+
+ | ``%%`` | A literal ``'%'`` character. | |
+ +-----------+--------------------------------+-------+
+
+ Notes:
+
+ (1)
+ When used with the :func:`strptime` function, the ``%p`` directive only affects
+ the output hour field if the ``%I`` directive is used to parse the hour.
+
+ (2)
+ The range really is ``0`` to ``61``; this accounts for leap seconds and the
+ (very rare) double leap seconds.
+
+ (3)
+ When used with the :func:`strptime` function, ``%U`` and ``%W`` are only used in
+ calculations when the day of the week and the year are specified.
+
+ Here is an example, a format for dates compatible with that specified in the
+ :rfc:`2822` Internet email standard. [#]_ ::
+
+ >>> from time import gmtime, strftime
+ >>> strftime("%a, %d %b %Y %H:%M:%S +0000", gmtime())
+ 'Thu, 28 Jun 2001 14:17:15 +0000'
+
+ Additional directives may be supported on certain platforms, but only the ones
+ listed here have a meaning standardized by ANSI C.
+
+ On some platforms, an optional field width and precision specification can
+ immediately follow the initial ``'%'`` of a directive in the following order;
+ this is also not portable. The field width is normally 2 except for ``%j`` where
+ it is 3.
+
+
+.. function:: strptime(string[, format])
+
+ Parse a string representing a time according to a format. The return value is
+ a :class:`struct_time` as returned by :func:`gmtime` or :func:`localtime`.
+
+ The *format* parameter uses the same directives as those used by
+ :func:`strftime`; it defaults to ``"%a %b %d %H:%M:%S %Y"`` which matches the
+ formatting returned by :func:`ctime`. If *string* cannot be parsed according to
+ *format*, or if it has excess data after parsing, :exc:`ValueError` is raised.
+ The default values used to fill in any missing data when more accurate values
+ cannot be inferred are ``(1900, 1, 1, 0, 0, 0, 0, 1, -1)``.
+
+ For example::
+
+ >>> import time
+ >>> time.strptime("30 Nov 00", "%d %b %y")
+ (2000, 11, 30, 0, 0, 0, 3, 335, -1)
+
+ Support for the ``%Z`` directive is based on the values contained in ``tzname``
+ and whether ``daylight`` is true. Because of this, it is platform-specific
+ except for recognizing UTC and GMT which are always known (and are considered to
+ be non-daylight savings timezones).
+
+ Only the directives specified in the documentation are supported. Because
+ ``strftime()`` is implemented per platform it can sometimes offer more
+ directives than those listed. But ``strptime()`` is independent of any platform
+ and thus does not necessarily support all directives available that are not
+ documented as supported.
+
+
+.. data:: struct_time
+
+ The type of the time value sequence returned by :func:`gmtime`,
+ :func:`localtime`, and :func:`strptime`.
+
+ .. versionadded:: 2.2
+
+
+.. function:: time()
+
+ Return the time as a floating point number expressed in seconds since the epoch,
+ in UTC. Note that even though the time is always returned as a floating point
+ number, not all systems provide time with a better precision than 1 second.
+ While this function normally returns non-decreasing values, it can return a
+ lower value than a previous call if the system clock has been set back between
+ the two calls.
+
+
+.. data:: timezone
+
+ The offset of the local (non-DST) timezone, in seconds west of UTC (negative in
+ most of Western Europe, positive in the US, zero in the UK).
+
+
+.. data:: tzname
+
+ A tuple of two strings: the first is the name of the local non-DST timezone, the
+ second is the name of the local DST timezone. If no DST timezone is defined,
+ the second string should not be used.
+
+
+.. function:: tzset()
+
+ Resets the time conversion rules used by the library routines. The environment
+ variable :envvar:`TZ` specifies how this is done.
+
+ .. versionadded:: 2.3
+
+ Availability: Unix.
+
+ .. note::
+
+ Although in many cases, changing the :envvar:`TZ` environment variable may
+ affect the output of functions like :func:`localtime` without calling
+ :func:`tzset`, this behavior should not be relied on.
+
+ The :envvar:`TZ` environment variable should contain no whitespace.
+
+ The standard format of the :envvar:`TZ` environment variable is (whitespace
+ added for clarity)::
+
+ std offset [dst [offset [,start[/time], end[/time]]]]
+
+ Where the components are:
+
+ ``std`` and ``dst``
+ Three or more alphanumerics giving the timezone abbreviations. These will be
+ propagated into time.tzname
+
+ ``offset``
+ The offset has the form: ``± hh[:mm[:ss]]``. This indicates the value
+ added the local time to arrive at UTC. If preceded by a '-', the timezone
+ is east of the Prime Meridian; otherwise, it is west. If no offset follows
+ dst, summer time is assumed to be one hour ahead of standard time.
+
+ ``start[/time], end[/time]``
+ Indicates when to change to and back from DST. The format of the
+ start and end dates are one of the following:
+
+ :samp:`J{n}`
+ The Julian day *n* (1 <= *n* <= 365). Leap days are not counted, so in
+ all years February 28 is day 59 and March 1 is day 60.
+
+ :samp:`{n}`
+ The zero-based Julian day (0 <= *n* <= 365). Leap days are counted, and
+ it is possible to refer to February 29.
+
+ :samp:`M{m}.{n}.{d}`
+ The *d*'th day (0 <= *d* <= 6) or week *n* of month *m* of the year (1
+ <= *n* <= 5, 1 <= *m* <= 12, where week 5 means "the last *d* day in
+ month *m*" which may occur in either the fourth or the fifth
+ week). Week 1 is the first week in which the *d*'th day occurs. Day
+ zero is Sunday.
+
+ ``time`` has the same format as ``offset`` except that no leading sign
+ ('-' or '+') is allowed. The default, if time is not given, is 02:00:00.
+
+ ::
+
+ >>> os.environ['TZ'] = 'EST+05EDT,M4.1.0,M10.5.0'
+ >>> time.tzset()
+ >>> time.strftime('%X %x %Z')
+ '02:07:36 05/08/03 EDT'
+ >>> os.environ['TZ'] = 'AEST-10AEDT-11,M10.5.0,M3.5.0'
+ >>> time.tzset()
+ >>> time.strftime('%X %x %Z')
+ '16:08:12 05/08/03 AEST'
+
+ On many Unix systems (including \*BSD, Linux, Solaris, and Darwin), it is more
+ convenient to use the system's zoneinfo (:manpage:`tzfile(5)`) database to
+ specify the timezone rules. To do this, set the :envvar:`TZ` environment
+ variable to the path of the required timezone datafile, relative to the root of
+ the systems 'zoneinfo' timezone database, usually located at
+ :file:`/usr/share/zoneinfo`. For example, ``'US/Eastern'``,
+ ``'Australia/Melbourne'``, ``'Egypt'`` or ``'Europe/Amsterdam'``. ::
+
+ >>> os.environ['TZ'] = 'US/Eastern'
+ >>> time.tzset()
+ >>> time.tzname
+ ('EST', 'EDT')
+ >>> os.environ['TZ'] = 'Egypt'
+ >>> time.tzset()
+ >>> time.tzname
+ ('EET', 'EEST')
+
+
+.. seealso::
+
+ Module :mod:`datetime`
+ More object-oriented interface to dates and times.
+
+ Module :mod:`locale`
+ Internationalization services. The locale settings can affect the return values
+ for some of the functions in the :mod:`time` module.
+
+ Module :mod:`calendar`
+ General calendar-related functions. :func:`timegm` is the inverse of
+ :func:`gmtime` from this module.
+
+.. rubric:: Footnotes
+
+.. [#] The use of ``%Z`` is now deprecated, but the ``%z`` escape that expands to the
+ preferred hour/minute offset is not supported by all ANSI C libraries. Also, a
+ strict reading of the original 1982 :rfc:`822` standard calls for a two-digit
+ year (%y rather than %Y), but practice moved to 4-digit years long before the
+ year 2000. The 4-digit year has been mandated by :rfc:`2822`, which obsoletes
+ :rfc:`822`.
+
diff --git a/Doc/library/timeit.rst b/Doc/library/timeit.rst
new file mode 100644
index 0000000000..8c0cda3adb
--- /dev/null
+++ b/Doc/library/timeit.rst
@@ -0,0 +1,243 @@
+
+:mod:`timeit` --- Measure execution time of small code snippets
+===============================================================
+
+.. module:: timeit
+ :synopsis: Measure the execution time of small code snippets.
+
+
+.. versionadded:: 2.3
+
+.. index::
+ single: Benchmarking
+ single: Performance
+
+This module provides a simple way to time small bits of Python code. It has both
+command line as well as callable interfaces. It avoids a number of common traps
+for measuring execution times. See also Tim Peters' introduction to the
+"Algorithms" chapter in the Python Cookbook, published by O'Reilly.
+
+The module defines the following public class:
+
+
+.. class:: Timer([stmt='pass' [, setup='pass' [, timer=<timer function>]]])
+
+ Class for timing execution speed of small code snippets.
+
+ The constructor takes a statement to be timed, an additional statement used for
+ setup, and a timer function. Both statements default to ``'pass'``; the timer
+ function is platform-dependent (see the module doc string). The statements may
+ contain newlines, as long as they don't contain multi-line string literals.
+
+ To measure the execution time of the first statement, use the :meth:`timeit`
+ method. The :meth:`repeat` method is a convenience to call :meth:`timeit`
+ multiple times and return a list of results.
+
+ .. versionchanged:: 2.6
+ The *stmt* and *setup* parameters can now also take objects that are callable
+ without arguments. This will embed calls to them in a timer function that will
+ then be executed by :meth:`timeit`. Note that the timing overhead is a little
+ larger in this case because of the extra function calls.
+
+
+.. method:: Timer.print_exc([file=None])
+
+ Helper to print a traceback from the timed code.
+
+ Typical use::
+
+ t = Timer(...) # outside the try/except
+ try:
+ t.timeit(...) # or t.repeat(...)
+ except:
+ t.print_exc()
+
+ The advantage over the standard traceback is that source lines in the compiled
+ template will be displayed. The optional *file* argument directs where the
+ traceback is sent; it defaults to ``sys.stderr``.
+
+
+.. method:: Timer.repeat([repeat=3 [, number=1000000]])
+
+ Call :meth:`timeit` a few times.
+
+ This is a convenience function that calls the :meth:`timeit` repeatedly,
+ returning a list of results. The first argument specifies how many times to
+ call :meth:`timeit`. The second argument specifies the *number* argument for
+ :func:`timeit`.
+
+ .. note::
+
+ It's tempting to calculate mean and standard deviation from the result vector
+ and report these. However, this is not very useful. In a typical case, the
+ lowest value gives a lower bound for how fast your machine can run the given
+ code snippet; higher values in the result vector are typically not caused by
+ variability in Python's speed, but by other processes interfering with your
+ timing accuracy. So the :func:`min` of the result is probably the only number
+ you should be interested in. After that, you should look at the entire vector
+ and apply common sense rather than statistics.
+
+
+.. method:: Timer.timeit([number=1000000])
+
+ Time *number* executions of the main statement. This executes the setup
+ statement once, and then returns the time it takes to execute the main statement
+ a number of times, measured in seconds as a float. The argument is the number
+ of times through the loop, defaulting to one million. The main statement, the
+ setup statement and the timer function to be used are passed to the constructor.
+
+ .. note::
+
+ By default, :meth:`timeit` temporarily turns off garbage collection during the
+ timing. The advantage of this approach is that it makes independent timings
+ more comparable. This disadvantage is that GC may be an important component of
+ the performance of the function being measured. If so, GC can be re-enabled as
+ the first statement in the *setup* string. For example::
+
+ timeit.Timer('for i in range(10): oct(i)', 'gc.enable()').timeit()
+
+Starting with version 2.6, the module also defines two convenience functions:
+
+
+.. function:: repeat(stmt[, setup[, timer[, repeat=3 [, number=1000000]]]])
+
+ Create a :class:`Timer` instance with the given statement, setup code and timer
+ function and run its :meth:`repeat` method with the given repeat count and
+ *number* executions.
+
+ .. versionadded:: 2.6
+
+
+.. function:: timeit(stmt[, setup[, timer[, number=1000000]]])
+
+ Create a :class:`Timer` instance with the given statement, setup code and timer
+ function and run its :meth:`timeit` method with *number* executions.
+
+ .. versionadded:: 2.6
+
+
+Command Line Interface
+----------------------
+
+When called as a program from the command line, the following form is used::
+
+ python -m timeit [-n N] [-r N] [-s S] [-t] [-c] [-h] [statement ...]
+
+where the following options are understood:
+
+-n N/:option:`--number=N`
+ how many times to execute 'statement'
+
+-r N/:option:`--repeat=N`
+ how many times to repeat the timer (default 3)
+
+-s S/:option:`--setup=S`
+ statement to be executed once initially (default ``'pass'``)
+
+-t/:option:`--time`
+ use :func:`time.time` (default on all platforms but Windows)
+
+-c/:option:`--clock`
+ use :func:`time.clock` (default on Windows)
+
+-v/:option:`--verbose`
+ print raw timing results; repeat for more digits precision
+
+-h/:option:`--help`
+ print a short usage message and exit
+
+A multi-line statement may be given by specifying each line as a separate
+statement argument; indented lines are possible by enclosing an argument in
+quotes and using leading spaces. Multiple :option:`-s` options are treated
+similarly.
+
+If :option:`-n` is not given, a suitable number of loops is calculated by trying
+successive powers of 10 until the total time is at least 0.2 seconds.
+
+The default timer function is platform dependent. On Windows,
+:func:`time.clock` has microsecond granularity but :func:`time.time`'s
+granularity is 1/60th of a second; on Unix, :func:`time.clock` has 1/100th of a
+second granularity and :func:`time.time` is much more precise. On either
+platform, the default timer functions measure wall clock time, not the CPU time.
+This means that other processes running on the same computer may interfere with
+the timing. The best thing to do when accurate timing is necessary is to repeat
+the timing a few times and use the best time. The :option:`-r` option is good
+for this; the default of 3 repetitions is probably enough in most cases. On
+Unix, you can use :func:`time.clock` to measure CPU time.
+
+.. note::
+
+ There is a certain baseline overhead associated with executing a pass statement.
+ The code here doesn't try to hide it, but you should be aware of it. The
+ baseline overhead can be measured by invoking the program without arguments.
+
+The baseline overhead differs between Python versions! Also, to fairly compare
+older Python versions to Python 2.3, you may want to use Python's :option:`-O`
+option for the older versions to avoid timing ``SET_LINENO`` instructions.
+
+
+Examples
+--------
+
+Here are two example sessions (one using the command line, one using the module
+interface) that compare the cost of using :func:`hasattr` vs.
+:keyword:`try`/:keyword:`except` to test for missing and present object
+attributes. ::
+
+ % timeit.py 'try:' ' str.__bool__' 'except AttributeError:' ' pass'
+ 100000 loops, best of 3: 15.7 usec per loop
+ % timeit.py 'if hasattr(str, "__bool__"): pass'
+ 100000 loops, best of 3: 4.26 usec per loop
+ % timeit.py 'try:' ' int.__bool__' 'except AttributeError:' ' pass'
+ 1000000 loops, best of 3: 1.43 usec per loop
+ % timeit.py 'if hasattr(int, "__bool__"): pass'
+ 100000 loops, best of 3: 2.23 usec per loop
+
+::
+
+ >>> import timeit
+ >>> s = """\
+ ... try:
+ ... str.__bool__
+ ... except AttributeError:
+ ... pass
+ ... """
+ >>> t = timeit.Timer(stmt=s)
+ >>> print "%.2f usec/pass" % (1000000 * t.timeit(number=100000)/100000)
+ 17.09 usec/pass
+ >>> s = """\
+ ... if hasattr(str, '__bool__'): pass
+ ... """
+ >>> t = timeit.Timer(stmt=s)
+ >>> print "%.2f usec/pass" % (1000000 * t.timeit(number=100000)/100000)
+ 4.85 usec/pass
+ >>> s = """\
+ ... try:
+ ... int.__bool__
+ ... except AttributeError:
+ ... pass
+ ... """
+ >>> t = timeit.Timer(stmt=s)
+ >>> print "%.2f usec/pass" % (1000000 * t.timeit(number=100000)/100000)
+ 1.97 usec/pass
+ >>> s = """\
+ ... if hasattr(int, '__bool__'): pass
+ ... """
+ >>> t = timeit.Timer(stmt=s)
+ >>> print "%.2f usec/pass" % (1000000 * t.timeit(number=100000)/100000)
+ 3.15 usec/pass
+
+To give the :mod:`timeit` module access to functions you define, you can pass a
+``setup`` parameter which contains an import statement::
+
+ def test():
+ "Stupid test function"
+ L = []
+ for i in range(100):
+ L.append(i)
+
+ if __name__=='__main__':
+ from timeit import Timer
+ t = Timer("test()", "from __main__ import test")
+ print t.timeit()
+
diff --git a/Doc/library/tix.rst b/Doc/library/tix.rst
new file mode 100644
index 0000000000..4701c1583c
--- /dev/null
+++ b/Doc/library/tix.rst
@@ -0,0 +1,602 @@
+:mod:`Tix` --- Extension widgets for Tk
+=======================================
+
+.. module:: Tix
+ :synopsis: Tk Extension Widgets for Tkinter
+.. sectionauthor:: Mike Clarkson <mikeclarkson@users.sourceforge.net>
+
+
+.. index:: single: Tix
+
+The :mod:`Tix` (Tk Interface Extension) module provides an additional rich set
+of widgets. Although the standard Tk library has many useful widgets, they are
+far from complete. The :mod:`Tix` library provides most of the commonly needed
+widgets that are missing from standard Tk: :class:`HList`, :class:`ComboBox`,
+:class:`Control` (a.k.a. SpinBox) and an assortment of scrollable widgets.
+:mod:`Tix` also includes many more widgets that are generally useful in a wide
+range of applications: :class:`NoteBook`, :class:`FileEntry`,
+:class:`PanedWindow`, etc; there are more than 40 of them.
+
+With all these new widgets, you can introduce new interaction techniques into
+applications, creating more useful and more intuitive user interfaces. You can
+design your application by choosing the most appropriate widgets to match the
+special needs of your application and users.
+
+
+.. seealso::
+
+ `Tix Homepage <http://tix.sourceforge.net/>`_
+ The home page for :mod:`Tix`. This includes links to additional documentation
+ and downloads.
+
+ `Tix Man Pages <http://tix.sourceforge.net/dist/current/man/>`_
+ On-line version of the man pages and reference material.
+
+ `Tix Programming Guide <http://tix.sourceforge.net/dist/current/docs/tix-book/tix.book.html>`_
+ On-line version of the programmer's reference material.
+
+ `Tix Development Applications <http://tix.sourceforge.net/Tide/>`_
+ Tix applications for development of Tix and Tkinter programs. Tide applications
+ work under Tk or Tkinter, and include :program:`TixInspect`, an inspector to
+ remotely modify and debug Tix/Tk/Tkinter applications.
+
+
+Using Tix
+---------
+
+
+.. class:: Tix(screenName[, baseName[, className]])
+
+ Toplevel widget of Tix which represents mostly the main window of an
+ application. It has an associated Tcl interpreter.
+
+ Classes in the :mod:`Tix` module subclasses the classes in the :mod:`Tkinter`
+ module. The former imports the latter, so to use :mod:`Tix` with Tkinter, all
+ you need to do is to import one module. In general, you can just import
+ :mod:`Tix`, and replace the toplevel call to :class:`Tkinter.Tk` with
+ :class:`Tix.Tk`::
+
+ import Tix
+ from Tkconstants import *
+ root = Tix.Tk()
+
+To use :mod:`Tix`, you must have the :mod:`Tix` widgets installed, usually
+alongside your installation of the Tk widgets. To test your installation, try
+the following::
+
+ import Tix
+ root = Tix.Tk()
+ root.tk.eval('package require Tix')
+
+If this fails, you have a Tk installation problem which must be resolved before
+proceeding. Use the environment variable :envvar:`TIX_LIBRARY` to point to the
+installed :mod:`Tix` library directory, and make sure you have the dynamic
+object library (:file:`tix8183.dll` or :file:`libtix8183.so`) in the same
+directory that contains your Tk dynamic object library (:file:`tk8183.dll` or
+:file:`libtk8183.so`). The directory with the dynamic object library should also
+have a file called :file:`pkgIndex.tcl` (case sensitive), which contains the
+line::
+
+ package ifneeded Tix 8.1 [list load "[file join $dir tix8183.dll]" Tix]
+
+.. % $ <-- bow to font-lock
+
+
+Tix Widgets
+-----------
+
+`Tix <http://tix.sourceforge.net/dist/current/man/html/TixCmd/TixIntro.htm>`_
+introduces over 40 widget classes to the :mod:`Tkinter` repertoire. There is a
+demo of all the :mod:`Tix` widgets in the :file:`Demo/tix` directory of the
+standard distribution.
+
+.. % The Python sample code is still being added to Python, hence commented out
+
+
+Basic Widgets
+^^^^^^^^^^^^^
+
+
+.. class:: Balloon()
+
+ A `Balloon
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixBalloon.htm>`_ that
+ pops up over a widget to provide help. When the user moves the cursor inside a
+ widget to which a Balloon widget has been bound, a small pop-up window with a
+ descriptive message will be shown on the screen.
+
+.. % Python Demo of:
+.. % \ulink{Balloon}{http://tix.sourceforge.net/dist/current/demos/samples/Balloon.tcl}
+
+
+.. class:: ButtonBox()
+
+ The `ButtonBox
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixButtonBox.htm>`_
+ widget creates a box of buttons, such as is commonly used for ``Ok Cancel``.
+
+.. % Python Demo of:
+.. % \ulink{ButtonBox}{http://tix.sourceforge.net/dist/current/demos/samples/BtnBox.tcl}
+
+
+.. class:: ComboBox()
+
+ The `ComboBox
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixComboBox.htm>`_
+ widget is similar to the combo box control in MS Windows. The user can select a
+ choice by either typing in the entry subwdget or selecting from the listbox
+ subwidget.
+
+.. % Python Demo of:
+.. % \ulink{ComboBox}{http://tix.sourceforge.net/dist/current/demos/samples/ComboBox.tcl}
+
+
+.. class:: Control()
+
+ The `Control
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixControl.htm>`_
+ widget is also known as the :class:`SpinBox` widget. The user can adjust the
+ value by pressing the two arrow buttons or by entering the value directly into
+ the entry. The new value will be checked against the user-defined upper and
+ lower limits.
+
+.. % Python Demo of:
+.. % \ulink{Control}{http://tix.sourceforge.net/dist/current/demos/samples/Control.tcl}
+
+
+.. class:: LabelEntry()
+
+ The `LabelEntry
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixLabelEntry.htm>`_
+ widget packages an entry widget and a label into one mega widget. It can be used
+ be used to simplify the creation of "entry-form" type of interface.
+
+.. % Python Demo of:
+.. % \ulink{LabelEntry}{http://tix.sourceforge.net/dist/current/demos/samples/LabEntry.tcl}
+
+
+.. class:: LabelFrame()
+
+ The `LabelFrame
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixLabelFrame.htm>`_
+ widget packages a frame widget and a label into one mega widget. To create
+ widgets inside a LabelFrame widget, one creates the new widgets relative to the
+ :attr:`frame` subwidget and manage them inside the :attr:`frame` subwidget.
+
+.. % Python Demo of:
+.. % \ulink{LabelFrame}{http://tix.sourceforge.net/dist/current/demos/samples/LabFrame.tcl}
+
+
+.. class:: Meter()
+
+ The `Meter
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixMeter.htm>`_ widget
+ can be used to show the progress of a background job which may take a long time
+ to execute.
+
+.. % Python Demo of:
+.. % \ulink{Meter}{http://tix.sourceforge.net/dist/current/demos/samples/Meter.tcl}
+
+
+.. class:: OptionMenu()
+
+ The `OptionMenu
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixOptionMenu.htm>`_
+ creates a menu button of options.
+
+.. % Python Demo of:
+.. % \ulink{OptionMenu}{http://tix.sourceforge.net/dist/current/demos/samples/OptMenu.tcl}
+
+
+.. class:: PopupMenu()
+
+ The `PopupMenu
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixPopupMenu.htm>`_
+ widget can be used as a replacement of the ``tk_popup`` command. The advantage
+ of the :mod:`Tix` :class:`PopupMenu` widget is it requires less application code
+ to manipulate.
+
+.. % Python Demo of:
+.. % \ulink{PopupMenu}{http://tix.sourceforge.net/dist/current/demos/samples/PopMenu.tcl}
+
+
+.. class:: Select()
+
+ The `Select
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixSelect.htm>`_ widget
+ is a container of button subwidgets. It can be used to provide radio-box or
+ check-box style of selection options for the user.
+
+.. % Python Demo of:
+.. % \ulink{Select}{http://tix.sourceforge.net/dist/current/demos/samples/Select.tcl}
+
+
+.. class:: StdButtonBox()
+
+ The `StdButtonBox
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixStdButtonBox.htm>`_
+ widget is a group of standard buttons for Motif-like dialog boxes.
+
+.. % Python Demo of:
+.. % \ulink{StdButtonBox}{http://tix.sourceforge.net/dist/current/demos/samples/StdBBox.tcl}
+
+
+File Selectors
+^^^^^^^^^^^^^^
+
+
+.. class:: DirList()
+
+ The `DirList
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixDirList.htm>`_
+ widget displays a list view of a directory, its previous directories and its
+ sub-directories. The user can choose one of the directories displayed in the
+ list or change to another directory.
+
+.. % Python Demo of:
+.. % \ulink{DirList}{http://tix.sourceforge.net/dist/current/demos/samples/DirList.tcl}
+
+
+.. class:: DirTree()
+
+ The `DirTree
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixDirTree.htm>`_
+ widget displays a tree view of a directory, its previous directories and its
+ sub-directories. The user can choose one of the directories displayed in the
+ list or change to another directory.
+
+.. % Python Demo of:
+.. % \ulink{DirTree}{http://tix.sourceforge.net/dist/current/demos/samples/DirTree.tcl}
+
+
+.. class:: DirSelectDialog()
+
+ The `DirSelectDialog
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixDirSelectDialog.htm>`_
+ widget presents the directories in the file system in a dialog window. The user
+ can use this dialog window to navigate through the file system to select the
+ desired directory.
+
+.. % Python Demo of:
+.. % \ulink{DirSelectDialog}{http://tix.sourceforge.net/dist/current/demos/samples/DirDlg.tcl}
+
+
+.. class:: DirSelectBox()
+
+ The :class:`DirSelectBox` is similar to the standard Motif(TM)
+ directory-selection box. It is generally used for the user to choose a
+ directory. DirSelectBox stores the directories mostly recently selected into
+ a ComboBox widget so that they can be quickly selected again.
+
+
+.. class:: ExFileSelectBox()
+
+ The `ExFileSelectBox
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixExFileSelectBox.htm>`_
+ widget is usually embedded in a tixExFileSelectDialog widget. It provides an
+ convenient method for the user to select files. The style of the
+ :class:`ExFileSelectBox` widget is very similar to the standard file dialog on
+ MS Windows 3.1.
+
+.. % Python Demo of:
+.. % \ulink{ExFileSelectDialog}{http://tix.sourceforge.net/dist/current/demos/samples/EFileDlg.tcl}
+
+
+.. class:: FileSelectBox()
+
+ The `FileSelectBox
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixFileSelectBox.htm>`_
+ is similar to the standard Motif(TM) file-selection box. It is generally used
+ for the user to choose a file. FileSelectBox stores the files mostly recently
+ selected into a :class:`ComboBox` widget so that they can be quickly selected
+ again.
+
+.. % Python Demo of:
+.. % \ulink{FileSelectDialog}{http://tix.sourceforge.net/dist/current/demos/samples/FileDlg.tcl}
+
+
+.. class:: FileEntry()
+
+ The `FileEntry
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixFileEntry.htm>`_
+ widget can be used to input a filename. The user can type in the filename
+ manually. Alternatively, the user can press the button widget that sits next to
+ the entry, which will bring up a file selection dialog.
+
+.. % Python Demo of:
+.. % \ulink{FileEntry}{http://tix.sourceforge.net/dist/current/demos/samples/FileEnt.tcl}
+
+
+Hierachical ListBox
+^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: HList()
+
+ The `HList
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixHList.htm>`_ widget
+ can be used to display any data that have a hierarchical structure, for example,
+ file system directory trees. The list entries are indented and connected by
+ branch lines according to their places in the hierarchy.
+
+.. % Python Demo of:
+.. % \ulink{HList}{http://tix.sourceforge.net/dist/current/demos/samples/HList1.tcl}
+
+
+.. class:: CheckList()
+
+ The `CheckList
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixCheckList.htm>`_
+ widget displays a list of items to be selected by the user. CheckList acts
+ similarly to the Tk checkbutton or radiobutton widgets, except it is capable of
+ handling many more items than checkbuttons or radiobuttons.
+
+.. % Python Demo of:
+.. % \ulink{ CheckList}{http://tix.sourceforge.net/dist/current/demos/samples/ChkList.tcl}
+.. % Python Demo of:
+.. % \ulink{ScrolledHList (1)}{http://tix.sourceforge.net/dist/current/demos/samples/SHList.tcl}
+.. % Python Demo of:
+.. % \ulink{ScrolledHList (2)}{http://tix.sourceforge.net/dist/current/demos/samples/SHList2.tcl}
+
+
+.. class:: Tree()
+
+ The `Tree
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixTree.htm>`_ widget
+ can be used to display hierarchical data in a tree form. The user can adjust the
+ view of the tree by opening or closing parts of the tree.
+
+.. % Python Demo of:
+.. % \ulink{Tree}{http://tix.sourceforge.net/dist/current/demos/samples/Tree.tcl}
+.. % Python Demo of:
+.. % \ulink{Tree (Dynamic)}{http://tix.sourceforge.net/dist/current/demos/samples/DynTree.tcl}
+
+
+Tabular ListBox
+^^^^^^^^^^^^^^^
+
+
+.. class:: TList()
+
+ The `TList
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixTList.htm>`_ widget
+ can be used to display data in a tabular format. The list entries of a
+ :class:`TList` widget are similar to the entries in the Tk listbox widget. The
+ main differences are (1) the :class:`TList` widget can display the list entries
+ in a two dimensional format and (2) you can use graphical images as well as
+ multiple colors and fonts for the list entries.
+
+.. % Python Demo of:
+.. % \ulink{ScrolledTList (1)}{http://tix.sourceforge.net/dist/current/demos/samples/STList1.tcl}
+.. % Python Demo of:
+.. % \ulink{ScrolledTList (2)}{http://tix.sourceforge.net/dist/current/demos/samples/STList2.tcl}
+.. % Grid has yet to be added to Python
+.. % \subsubsection{Grid Widget}
+.. % Python Demo of:
+.. % \ulink{Simple Grid}{http://tix.sourceforge.net/dist/current/demos/samples/SGrid0.tcl}
+.. % Python Demo of:
+.. % \ulink{ScrolledGrid}{http://tix.sourceforge.net/dist/current/demos/samples/SGrid1.tcl}
+.. % Python Demo of:
+.. % \ulink{Editable Grid}{http://tix.sourceforge.net/dist/current/demos/samples/EditGrid.tcl}
+
+
+Manager Widgets
+^^^^^^^^^^^^^^^
+
+
+.. class:: PanedWindow()
+
+ The `PanedWindow
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixPanedWindow.htm>`_
+ widget allows the user to interactively manipulate the sizes of several panes.
+ The panes can be arranged either vertically or horizontally. The user changes
+ the sizes of the panes by dragging the resize handle between two panes.
+
+.. % Python Demo of:
+.. % \ulink{PanedWindow}{http://tix.sourceforge.net/dist/current/demos/samples/PanedWin.tcl}
+
+
+.. class:: ListNoteBook()
+
+ The `ListNoteBook
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixListNoteBook.htm>`_
+ widget is very similar to the :class:`TixNoteBook` widget: it can be used to
+ display many windows in a limited space using a notebook metaphor. The notebook
+ is divided into a stack of pages (windows). At one time only one of these pages
+ can be shown. The user can navigate through these pages by choosing the name of
+ the desired page in the :attr:`hlist` subwidget.
+
+.. % Python Demo of:
+.. % \ulink{ListNoteBook}{http://tix.sourceforge.net/dist/current/demos/samples/ListNBK.tcl}
+
+
+.. class:: NoteBook()
+
+ The `NoteBook
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixNoteBook.htm>`_
+ widget can be used to display many windows in a limited space using a notebook
+ metaphor. The notebook is divided into a stack of pages. At one time only one of
+ these pages can be shown. The user can navigate through these pages by choosing
+ the visual "tabs" at the top of the NoteBook widget.
+
+.. % Python Demo of:
+.. % \ulink{NoteBook}{http://tix.sourceforge.net/dist/current/demos/samples/NoteBook.tcl}
+
+.. % \subsubsection{Scrolled Widgets}
+.. % Python Demo of:
+.. % \ulink{ScrolledListBox}{http://tix.sourceforge.net/dist/current/demos/samples/SListBox.tcl}
+.. % Python Demo of:
+.. % \ulink{ScrolledText}{http://tix.sourceforge.net/dist/current/demos/samples/SText.tcl}
+.. % Python Demo of:
+.. % \ulink{ScrolledWindow}{http://tix.sourceforge.net/dist/current/demos/samples/SWindow.tcl}
+.. % Python Demo of:
+.. % \ulink{Canvas Object View}{http://tix.sourceforge.net/dist/current/demos/samples/CObjView.tcl}
+
+
+Image Types
+^^^^^^^^^^^
+
+The :mod:`Tix` module adds:
+
+* `pixmap <http://tix.sourceforge.net/dist/current/man/html/TixCmd/pixmap.htm>`_
+ capabilities to all :mod:`Tix` and :mod:`Tkinter` widgets to create color images
+ from XPM files.
+
+ .. % Python Demo of:
+ .. % \ulink{XPM Image In Button}{http://tix.sourceforge.net/dist/current/demos/samples/Xpm.tcl}
+ .. % Python Demo of:
+ .. % \ulink{XPM Image In Menu}{http://tix.sourceforge.net/dist/current/demos/samples/Xpm1.tcl}
+
+* `Compound
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/compound.htm>`_ image
+ types can be used to create images that consists of multiple horizontal lines;
+ each line is composed of a series of items (texts, bitmaps, images or spaces)
+ arranged from left to right. For example, a compound image can be used to
+ display a bitmap and a text string simultaneously in a Tk :class:`Button`
+ widget.
+
+ .. % Python Demo of:
+ .. % \ulink{Compound Image In Buttons}{http://tix.sourceforge.net/dist/current/demos/samples/CmpImg.tcl}
+ .. % Python Demo of:
+ .. % \ulink{Compound Image In NoteBook}{http://tix.sourceforge.net/dist/current/demos/samples/CmpImg2.tcl}
+ .. % Python Demo of:
+ .. % \ulink{Compound Image Notebook Color Tabs}{http://tix.sourceforge.net/dist/current/demos/samples/CmpImg4.tcl}
+ .. % Python Demo of:
+ .. % \ulink{Compound Image Icons}{http://tix.sourceforge.net/dist/current/demos/samples/CmpImg3.tcl}
+
+
+Miscellaneous Widgets
+^^^^^^^^^^^^^^^^^^^^^
+
+
+.. class:: InputOnly()
+
+ The `InputOnly
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixInputOnly.htm>`_
+ widgets are to accept inputs from the user, which can be done with the ``bind``
+ command (Unix only).
+
+
+Form Geometry Manager
+^^^^^^^^^^^^^^^^^^^^^
+
+In addition, :mod:`Tix` augments :mod:`Tkinter` by providing:
+
+
+.. class:: Form()
+
+ The `Form
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tixForm.htm>`_ geometry
+ manager based on attachment rules for all Tk widgets.
+
+.. % begin{latexonly}
+.. % \subsection{Tix Class Structure}
+.. %
+.. % \begin{figure}[hbtp]
+.. % \centerline{\epsfig{file=hierarchy.png,width=.9\textwidth}}
+.. % \vspace{.5cm}
+.. % \caption{The Class Hierarchy of Tix Widgets}
+.. % \end{figure}
+.. % end{latexonly}
+
+
+Tix Commands
+------------
+
+
+.. class:: tixCommand()
+
+ The `tix commands
+ <http://tix.sourceforge.net/dist/current/man/html/TixCmd/tix.htm>`_ provide
+ access to miscellaneous elements of :mod:`Tix`'s internal state and the
+ :mod:`Tix` application context. Most of the information manipulated by these
+ methods pertains to the application as a whole, or to a screen or display,
+ rather than to a particular window.
+
+ To view the current settings, the common usage is::
+
+ import Tix
+ root = Tix.Tk()
+ print root.tix_configure()
+
+
+.. method:: tixCommand.tix_configure([cnf,] **kw)
+
+ Query or modify the configuration options of the Tix application context. If no
+ option is specified, returns a dictionary all of the available options. If
+ option is specified with no value, then the method returns a list describing the
+ one named option (this list will be identical to the corresponding sublist of
+ the value returned if no option is specified). If one or more option-value
+ pairs are specified, then the method modifies the given option(s) to have the
+ given value(s); in this case the method returns an empty string. Option may be
+ any of the configuration options.
+
+
+.. method:: tixCommand.tix_cget(option)
+
+ Returns the current value of the configuration option given by *option*. Option
+ may be any of the configuration options.
+
+
+.. method:: tixCommand.tix_getbitmap(name)
+
+ Locates a bitmap file of the name ``name.xpm`` or ``name`` in one of the bitmap
+ directories (see the :meth:`tix_addbitmapdir` method). By using
+ :meth:`tix_getbitmap`, you can avoid hard coding the pathnames of the bitmap
+ files in your application. When successful, it returns the complete pathname of
+ the bitmap file, prefixed with the character ``@``. The returned value can be
+ used to configure the ``bitmap`` option of the Tk and Tix widgets.
+
+
+.. method:: tixCommand.tix_addbitmapdir(directory)
+
+ Tix maintains a list of directories under which the :meth:`tix_getimage` and
+ :meth:`tix_getbitmap` methods will search for image files. The standard bitmap
+ directory is :file:`$TIX_LIBRARY/bitmaps`. The :meth:`tix_addbitmapdir` method
+ adds *directory* into this list. By using this method, the image files of an
+ applications can also be located using the :meth:`tix_getimage` or
+ :meth:`tix_getbitmap` method.
+
+
+.. method:: tixCommand.tix_filedialog([dlgclass])
+
+ Returns the file selection dialog that may be shared among different calls from
+ this application. This method will create a file selection dialog widget when
+ it is called the first time. This dialog will be returned by all subsequent
+ calls to :meth:`tix_filedialog`. An optional dlgclass parameter can be passed
+ as a string to specified what type of file selection dialog widget is desired.
+ Possible options are ``tix``, ``FileSelectDialog`` or ``tixExFileSelectDialog``.
+
+
+.. method:: tixCommand.tix_getimage(self, name)
+
+ Locates an image file of the name :file:`name.xpm`, :file:`name.xbm` or
+ :file:`name.ppm` in one of the bitmap directories (see the
+ :meth:`tix_addbitmapdir` method above). If more than one file with the same name
+ (but different extensions) exist, then the image type is chosen according to the
+ depth of the X display: xbm images are chosen on monochrome displays and color
+ images are chosen on color displays. By using :meth:`tix_getimage`, you can
+ avoid hard coding the pathnames of the image files in your application. When
+ successful, this method returns the name of the newly created image, which can
+ be used to configure the ``image`` option of the Tk and Tix widgets.
+
+
+.. method:: tixCommand.tix_option_get(name)
+
+ Gets the options maintained by the Tix scheme mechanism.
+
+
+.. method:: tixCommand.tix_resetoptions(newScheme, newFontSet[, newScmPrio])
+
+ Resets the scheme and fontset of the Tix application to *newScheme* and
+ *newFontSet*, respectively. This affects only those widgets created after this
+ call. Therefore, it is best to call the resetoptions method before the creation
+ of any widgets in a Tix application.
+
+ The optional parameter *newScmPrio* can be given to reset the priority level of
+ the Tk options set by the Tix schemes.
+
+ Because of the way Tk handles the X option database, after Tix has been has
+ imported and inited, it is not possible to reset the color schemes and font sets
+ using the :meth:`tix_config` method. Instead, the :meth:`tix_resetoptions`
+ method must be used.
diff --git a/Doc/library/tk.rst b/Doc/library/tk.rst
new file mode 100644
index 0000000000..bb852d2d88
--- /dev/null
+++ b/Doc/library/tk.rst
@@ -0,0 +1,43 @@
+.. _tkinter:
+
+*********************************
+Graphical User Interfaces with Tk
+*********************************
+
+.. index::
+ single: GUI
+ single: Graphical User Interface
+ single: Tkinter
+ single: Tk
+
+Tk/Tcl has long been an integral part of Python. It provides a robust and
+platform independent windowing toolkit, that is available to Python programmers
+using the :mod:`Tkinter` module, and its extension, the :mod:`Tix` module.
+
+The :mod:`Tkinter` module is a thin object-oriented layer on top of Tcl/Tk. To
+use :mod:`Tkinter`, you don't need to write Tcl code, but you will need to
+consult the Tk documentation, and occasionally the Tcl documentation.
+:mod:`Tkinter` is a set of wrappers that implement the Tk widgets as Python
+classes. In addition, the internal module :mod:`_tkinter` provides a threadsafe
+mechanism which allows Python and Tcl to interact.
+
+:mod:`Tkinter`'s chief virtues are that it is fast, and that it usually comes
+bundled with Python. Although it has been used to create some very good
+applications, including IDLE, it has weak documentation and an outdated look and
+feel. For more modern, better documented, and much more extensive GUI
+libraries, see the :ref:`other-gui-packages` section.
+
+.. toctree::
+
+ tkinter.rst
+ tix.rst
+ scrolledtext.rst
+ turtle.rst
+ idle.rst
+ othergui.rst
+
+.. % Other sections I have in mind are
+.. % Tkinter internals
+.. % Freezing Tkinter applications
+
+
diff --git a/Doc/library/tkinter.rst b/Doc/library/tkinter.rst
new file mode 100644
index 0000000000..d52c1e0b57
--- /dev/null
+++ b/Doc/library/tkinter.rst
@@ -0,0 +1,840 @@
+:mod:`Tkinter` --- Python interface to Tcl/Tk
+=============================================
+
+.. module:: Tkinter
+ :synopsis: Interface to Tcl/Tk for graphical user interfaces
+.. moduleauthor:: Guido van Rossum <guido@Python.org>
+
+
+The :mod:`Tkinter` module ("Tk interface") is the standard Python interface to
+the Tk GUI toolkit. Both Tk and :mod:`Tkinter` are available on most Unix
+platforms, as well as on Windows and Macintosh systems. (Tk itself is not part
+of Python; it is maintained at ActiveState.)
+
+
+.. seealso::
+
+ `Python Tkinter Resources <http://www.python.org/topics/tkinter/>`_
+ The Python Tkinter Topic Guide provides a great deal of information on using Tk
+ from Python and links to other sources of information on Tk.
+
+ `An Introduction to Tkinter <http://www.pythonware.com/library/an-introduction-to-tkinter.htm>`_
+ Fredrik Lundh's on-line reference material.
+
+ `Tkinter reference: a GUI for Python <http://www.nmt.edu/tcc/help/pubs/lang.html>`_
+ On-line reference material.
+
+ `Tkinter for JPython <http://jtkinter.sourceforge.net>`_
+ The Jython interface to Tkinter.
+
+ `Python and Tkinter Programming <http://www.amazon.com/exec/obidos/ASIN/1884777813>`_
+ The book by John Grayson (ISBN 1-884777-81-3).
+
+
+Tkinter Modules
+---------------
+
+Most of the time, the :mod:`Tkinter` module is all you really need, but a number
+of additional modules are available as well. The Tk interface is located in a
+binary module named :mod:`_tkinter`. This module contains the low-level
+interface to Tk, and should never be used directly by application programmers.
+It is usually a shared library (or DLL), but might in some cases be statically
+linked with the Python interpreter.
+
+In addition to the Tk interface module, :mod:`Tkinter` includes a number of
+Python modules. The two most important modules are the :mod:`Tkinter` module
+itself, and a module called :mod:`Tkconstants`. The former automatically imports
+the latter, so to use Tkinter, all you need to do is to import one module::
+
+ import Tkinter
+
+Or, more often::
+
+ from Tkinter import *
+
+
+.. class:: Tk(screenName=None, baseName=None, className='Tk', useTk=1)
+
+ The :class:`Tk` class is instantiated without arguments. This creates a toplevel
+ widget of Tk which usually is the main window of an application. Each instance
+ has its own associated Tcl interpreter.
+
+ .. % FIXME: The following keyword arguments are currently recognized:
+
+ .. versionchanged:: 2.4
+ The *useTk* parameter was added.
+
+
+.. function:: Tcl(screenName=None, baseName=None, className='Tk', useTk=0)
+
+ The :func:`Tcl` function is a factory function which creates an object much like
+ that created by the :class:`Tk` class, except that it does not initialize the Tk
+ subsystem. This is most often useful when driving the Tcl interpreter in an
+ environment where one doesn't want to create extraneous toplevel windows, or
+ where one cannot (such as Unix/Linux systems without an X server). An object
+ created by the :func:`Tcl` object can have a Toplevel window created (and the Tk
+ subsystem initialized) by calling its :meth:`loadtk` method.
+
+ .. versionadded:: 2.4
+
+Other modules that provide Tk support include:
+
+:mod:`ScrolledText`
+ Text widget with a vertical scroll bar built in.
+
+:mod:`tkColorChooser`
+ Dialog to let the user choose a color.
+
+:mod:`tkCommonDialog`
+ Base class for the dialogs defined in the other modules listed here.
+
+:mod:`tkFileDialog`
+ Common dialogs to allow the user to specify a file to open or save.
+
+:mod:`tkFont`
+ Utilities to help work with fonts.
+
+:mod:`tkMessageBox`
+ Access to standard Tk dialog boxes.
+
+:mod:`tkSimpleDialog`
+ Basic dialogs and convenience functions.
+
+:mod:`Tkdnd`
+ Drag-and-drop support for :mod:`Tkinter`. This is experimental and should become
+ deprecated when it is replaced with the Tk DND.
+
+:mod:`turtle`
+ Turtle graphics in a Tk window.
+
+
+Tkinter Life Preserver
+----------------------
+
+.. sectionauthor:: Matt Conway
+
+
+This section is not designed to be an exhaustive tutorial on either Tk or
+Tkinter. Rather, it is intended as a stop gap, providing some introductory
+orientation on the system.
+
+.. % Converted to LaTeX by Mike Clarkson.
+
+Credits:
+
+* Tkinter was written by Steen Lumholt and Guido van Rossum.
+
+* Tk was written by John Ousterhout while at Berkeley.
+
+* This Life Preserver was written by Matt Conway at the University of Virginia.
+
+* The html rendering, and some liberal editing, was produced from a FrameMaker
+ version by Ken Manheimer.
+
+* Fredrik Lundh elaborated and revised the class interface descriptions, to get
+ them current with Tk 4.2.
+
+* Mike Clarkson converted the documentation to LaTeX, and compiled the User
+ Interface chapter of the reference manual.
+
+
+How To Use This Section
+^^^^^^^^^^^^^^^^^^^^^^^
+
+This section is designed in two parts: the first half (roughly) covers
+background material, while the second half can be taken to the keyboard as a
+handy reference.
+
+When trying to answer questions of the form "how do I do blah", it is often best
+to find out how to do"blah" in straight Tk, and then convert this back into the
+corresponding :mod:`Tkinter` call. Python programmers can often guess at the
+correct Python command by looking at the Tk documentation. This means that in
+order to use Tkinter, you will have to know a little bit about Tk. This document
+can't fulfill that role, so the best we can do is point you to the best
+documentation that exists. Here are some hints:
+
+* The authors strongly suggest getting a copy of the Tk man pages. Specifically,
+ the man pages in the ``mann`` directory are most useful. The ``man3`` man pages
+ describe the C interface to the Tk library and thus are not especially helpful
+ for script writers.
+
+* Addison-Wesley publishes a book called Tcl and the Tk Toolkit by John
+ Ousterhout (ISBN 0-201-63337-X) which is a good introduction to Tcl and Tk for
+ the novice. The book is not exhaustive, and for many details it defers to the
+ man pages.
+
+* :file:`Tkinter.py` is a last resort for most, but can be a good place to go
+ when nothing else makes sense.
+
+
+.. seealso::
+
+ `ActiveState Tcl Home Page <http://tcl.activestate.com/>`_
+ The Tk/Tcl development is largely taking place at ActiveState.
+
+ `Tcl and the Tk Toolkit <http://www.amazon.com/exec/obidos/ASIN/020163337X>`_
+ The book by John Ousterhout, the inventor of Tcl .
+
+ `Practical Programming in Tcl and Tk <http://www.amazon.com/exec/obidos/ASIN/0130220280>`_
+ Brent Welch's encyclopedic book.
+
+
+A Simple Hello World Program
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. % HelloWorld.html
+.. % begin{latexonly}
+.. % \begin{figure}[hbtp]
+.. % \centerline{\epsfig{file=HelloWorld.gif,width=.9\textwidth}}
+.. % \vspace{.5cm}
+.. % \caption{HelloWorld gadget image}
+.. % \end{figure}
+.. % See also the hello-world \ulink{notes}{classes/HelloWorld-notes.html} and
+.. % \ulink{summary}{classes/HelloWorld-summary.html}.
+.. % end{latexonly}
+
+::
+
+ from Tkinter import *
+
+ class Application(Frame):
+ def say_hi(self):
+ print "hi there, everyone!"
+
+ def createWidgets(self):
+ self.QUIT = Button(self)
+ self.QUIT["text"] = "QUIT"
+ self.QUIT["fg"] = "red"
+ self.QUIT["command"] = self.quit
+
+ self.QUIT.pack({"side": "left"})
+
+ self.hi_there = Button(self)
+ self.hi_there["text"] = "Hello",
+ self.hi_there["command"] = self.say_hi
+
+ self.hi_there.pack({"side": "left"})
+
+ def __init__(self, master=None):
+ Frame.__init__(self, master)
+ self.pack()
+ self.createWidgets()
+
+ root = Tk()
+ app = Application(master=root)
+ app.mainloop()
+ root.destroy()
+
+
+A (Very) Quick Look at Tcl/Tk
+-----------------------------
+
+The class hierarchy looks complicated, but in actual practice, application
+programmers almost always refer to the classes at the very bottom of the
+hierarchy.
+
+.. % BriefTclTk.html
+
+Notes:
+
+* These classes are provided for the purposes of organizing certain functions
+ under one namespace. They aren't meant to be instantiated independently.
+
+* The :class:`Tk` class is meant to be instantiated only once in an application.
+ Application programmers need not instantiate one explicitly, the system creates
+ one whenever any of the other classes are instantiated.
+
+* The :class:`Widget` class is not meant to be instantiated, it is meant only
+ for subclassing to make "real" widgets (in C++, this is called an 'abstract
+ class').
+
+To make use of this reference material, there will be times when you will need
+to know how to read short passages of Tk and how to identify the various parts
+of a Tk command. (See section :ref:`tkinter-basic-mapping` for the
+:mod:`Tkinter` equivalents of what's below.)
+
+Tk scripts are Tcl programs. Like all Tcl programs, Tk scripts are just lists
+of tokens separated by spaces. A Tk widget is just its *class*, the *options*
+that help configure it, and the *actions* that make it do useful things.
+
+To make a widget in Tk, the command is always of the form::
+
+ classCommand newPathname options
+
+*classCommand*
+ denotes which kind of widget to make (a button, a label, a menu...)
+
+*newPathname*
+ is the new name for this widget. All names in Tk must be unique. To help
+ enforce this, widgets in Tk are named with *pathnames*, just like files in a
+ file system. The top level widget, the *root*, is called ``.`` (period) and
+ children are delimited by more periods. For example,
+ ``.myApp.controlPanel.okButton`` might be the name of a widget.
+
+*options*
+ configure the widget's appearance and in some cases, its behavior. The options
+ come in the form of a list of flags and values. Flags are preceded by a '-',
+ like Unix shell command flags, and values are put in quotes if they are more
+ than one word.
+
+For example::
+
+ button .fred -fg red -text "hi there"
+ ^ ^ \_____________________/
+ | | |
+ class new options
+ command widget (-opt val -opt val ...)
+
+Once created, the pathname to the widget becomes a new command. This new
+*widget command* is the programmer's handle for getting the new widget to
+perform some *action*. In C, you'd express this as someAction(fred,
+someOptions), in C++, you would express this as fred.someAction(someOptions),
+and in Tk, you say::
+
+ .fred someAction someOptions
+
+Note that the object name, ``.fred``, starts with a dot.
+
+As you'd expect, the legal values for *someAction* will depend on the widget's
+class: ``.fred disable`` works if fred is a button (fred gets greyed out), but
+does not work if fred is a label (disabling of labels is not supported in Tk).
+
+The legal values of *someOptions* is action dependent. Some actions, like
+``disable``, require no arguments, others, like a text-entry box's ``delete``
+command, would need arguments to specify what range of text to delete.
+
+
+.. _tkinter-basic-mapping:
+
+Mapping Basic Tk into Tkinter
+-----------------------------
+
+Class commands in Tk correspond to class constructors in Tkinter. ::
+
+ button .fred =====> fred = Button()
+
+The master of an object is implicit in the new name given to it at creation
+time. In Tkinter, masters are specified explicitly. ::
+
+ button .panel.fred =====> fred = Button(panel)
+
+The configuration options in Tk are given in lists of hyphened tags followed by
+values. In Tkinter, options are specified as keyword-arguments in the instance
+constructor, and keyword-args for configure calls or as instance indices, in
+dictionary style, for established instances. See section
+:ref:`tkinter-setting-options` on setting options. ::
+
+ button .fred -fg red =====> fred = Button(panel, fg = "red")
+ .fred configure -fg red =====> fred["fg"] = red
+ OR ==> fred.config(fg = "red")
+
+In Tk, to perform an action on a widget, use the widget name as a command, and
+follow it with an action name, possibly with arguments (options). In Tkinter,
+you call methods on the class instance to invoke actions on the widget. The
+actions (methods) that a given widget can perform are listed in the Tkinter.py
+module. ::
+
+ .fred invoke =====> fred.invoke()
+
+To give a widget to the packer (geometry manager), you call pack with optional
+arguments. In Tkinter, the Pack class holds all this functionality, and the
+various forms of the pack command are implemented as methods. All widgets in
+:mod:`Tkinter` are subclassed from the Packer, and so inherit all the packing
+methods. See the :mod:`Tix` module documentation for additional information on
+the Form geometry manager. ::
+
+ pack .fred -side left =====> fred.pack(side = "left")
+
+
+How Tk and Tkinter are Related
+------------------------------
+
+.. % Relationship.html
+
+.. note::
+
+ This was derived from a graphical image; the image will be used more directly in
+ a subsequent version of this document.
+
+From the top down:
+
+Your App Here (Python)
+ A Python application makes a :mod:`Tkinter` call.
+
+Tkinter (Python Module)
+ This call (say, for example, creating a button widget), is implemented in the
+ *Tkinter* module, which is written in Python. This Python function will parse
+ the commands and the arguments and convert them into a form that makes them look
+ as if they had come from a Tk script instead of a Python script.
+
+tkinter (C)
+ These commands and their arguments will be passed to a C function in the
+ *tkinter* - note the lowercase - extension module.
+
+Tk Widgets (C and Tcl)
+ This C function is able to make calls into other C modules, including the C
+ functions that make up the Tk library. Tk is implemented in C and some Tcl.
+ The Tcl part of the Tk widgets is used to bind certain default behaviors to
+ widgets, and is executed once at the point where the Python :mod:`Tkinter`
+ module is imported. (The user never sees this stage).
+
+Tk (C)
+ The Tk part of the Tk Widgets implement the final mapping to ...
+
+Xlib (C)
+ the Xlib library to draw graphics on the screen.
+
+
+Handy Reference
+---------------
+
+
+.. _tkinter-setting-options:
+
+Setting Options
+^^^^^^^^^^^^^^^
+
+Options control things like the color and border width of a widget. Options can
+be set in three ways:
+
+At object creation time, using keyword arguments
+ ::
+
+ fred = Button(self, fg = "red", bg = "blue")
+
+After object creation, treating the option name like a dictionary index
+ ::
+
+ fred["fg"] = "red"
+ fred["bg"] = "blue"
+
+Use the config() method to update multiple attrs subsequent to object creation
+ ::
+
+ fred.config(fg = "red", bg = "blue")
+
+For a complete explanation of a given option and its behavior, see the Tk man
+pages for the widget in question.
+
+Note that the man pages list "STANDARD OPTIONS" and "WIDGET SPECIFIC OPTIONS"
+for each widget. The former is a list of options that are common to many
+widgets, the latter are the options that are idiosyncratic to that particular
+widget. The Standard Options are documented on the :manpage:`options(3)` man
+page.
+
+No distinction between standard and widget-specific options is made in this
+document. Some options don't apply to some kinds of widgets. Whether a given
+widget responds to a particular option depends on the class of the widget;
+buttons have a ``command`` option, labels do not.
+
+The options supported by a given widget are listed in that widget's man page, or
+can be queried at runtime by calling the :meth:`config` method without
+arguments, or by calling the :meth:`keys` method on that widget. The return
+value of these calls is a dictionary whose key is the name of the option as a
+string (for example, ``'relief'``) and whose values are 5-tuples.
+
+Some options, like ``bg`` are synonyms for common options with long names
+(``bg`` is shorthand for "background"). Passing the ``config()`` method the name
+of a shorthand option will return a 2-tuple, not 5-tuple. The 2-tuple passed
+back will contain the name of the synonym and the "real" option (such as
+``('bg', 'background')``).
+
++-------+---------------------------------+--------------+
+| Index | Meaning | Example |
++=======+=================================+==============+
+| 0 | option name | ``'relief'`` |
++-------+---------------------------------+--------------+
+| 1 | option name for database lookup | ``'relief'`` |
++-------+---------------------------------+--------------+
+| 2 | option class for database | ``'Relief'`` |
+| | lookup | |
++-------+---------------------------------+--------------+
+| 3 | default value | ``'raised'`` |
++-------+---------------------------------+--------------+
+| 4 | current value | ``'groove'`` |
++-------+---------------------------------+--------------+
+
+Example::
+
+ >>> print fred.config()
+ {'relief' : ('relief', 'relief', 'Relief', 'raised', 'groove')}
+
+Of course, the dictionary printed will include all the options available and
+their values. This is meant only as an example.
+
+
+The Packer
+^^^^^^^^^^
+
+.. index:: single: packing (widgets)
+
+.. % Packer.html
+
+The packer is one of Tk's geometry-management mechanisms. Geometry managers
+are used to specify the relative positioning of the positioning of widgets
+within their container - their mutual *master*. In contrast to the more
+cumbersome *placer* (which is used less commonly, and we do not cover here), the
+packer takes qualitative relationship specification - *above*, *to the left of*,
+*filling*, etc - and works everything out to determine the exact placement
+coordinates for you.
+
+.. % See also \citetitle[classes/ClassPacker.html]{the Packer class interface}.
+
+The size of any *master* widget is determined by the size of the "slave widgets"
+inside. The packer is used to control where slave widgets appear inside the
+master into which they are packed. You can pack widgets into frames, and frames
+into other frames, in order to achieve the kind of layout you desire.
+Additionally, the arrangement is dynamically adjusted to accommodate incremental
+changes to the configuration, once it is packed.
+
+Note that widgets do not appear until they have had their geometry specified
+with a geometry manager. It's a common early mistake to leave out the geometry
+specification, and then be surprised when the widget is created but nothing
+appears. A widget will appear only after it has had, for example, the packer's
+:meth:`pack` method applied to it.
+
+The pack() method can be called with keyword-option/value pairs that control
+where the widget is to appear within its container, and how it is to behave when
+the main application window is resized. Here are some examples::
+
+ fred.pack() # defaults to side = "top"
+ fred.pack(side = "left")
+ fred.pack(expand = 1)
+
+
+Packer Options
+^^^^^^^^^^^^^^
+
+For more extensive information on the packer and the options that it can take,
+see the man pages and page 183 of John Ousterhout's book.
+
+anchor
+ Anchor type. Denotes where the packer is to place each slave in its parcel.
+
+expand
+ Boolean, ``0`` or ``1``.
+
+fill
+ Legal values: ``'x'``, ``'y'``, ``'both'``, ``'none'``.
+
+ipadx and ipady
+ A distance - designating internal padding on each side of the slave widget.
+
+padx and pady
+ A distance - designating external padding on each side of the slave widget.
+
+side
+ Legal values are: ``'left'``, ``'right'``, ``'top'``, ``'bottom'``.
+
+
+Coupling Widget Variables
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The current-value setting of some widgets (like text entry widgets) can be
+connected directly to application variables by using special options. These
+options are ``variable``, ``textvariable``, ``onvalue``, ``offvalue``, and
+``value``. This connection works both ways: if the variable changes for any
+reason, the widget it's connected to will be updated to reflect the new value.
+
+.. % VarCouplings.html
+
+Unfortunately, in the current implementation of :mod:`Tkinter` it is not
+possible to hand over an arbitrary Python variable to a widget through a
+``variable`` or ``textvariable`` option. The only kinds of variables for which
+this works are variables that are subclassed from a class called Variable,
+defined in the :mod:`Tkinter` module.
+
+There are many useful subclasses of Variable already defined:
+:class:`StringVar`, :class:`IntVar`, :class:`DoubleVar`, and
+:class:`BooleanVar`. To read the current value of such a variable, call the
+:meth:`get` method on it, and to change its value you call the :meth:`set`
+method. If you follow this protocol, the widget will always track the value of
+the variable, with no further intervention on your part.
+
+For example::
+
+ class App(Frame):
+ def __init__(self, master=None):
+ Frame.__init__(self, master)
+ self.pack()
+
+ self.entrythingy = Entry()
+ self.entrythingy.pack()
+
+ # here is the application variable
+ self.contents = StringVar()
+ # set it to some value
+ self.contents.set("this is a variable")
+ # tell the entry widget to watch this variable
+ self.entrythingy["textvariable"] = self.contents
+
+ # and here we get a callback when the user hits return.
+ # we will have the program print out the value of the
+ # application variable when the user hits return
+ self.entrythingy.bind('<Key-Return>',
+ self.print_contents)
+
+ def print_contents(self, event):
+ print "hi. contents of entry is now ---->", \
+ self.contents.get()
+
+
+The Window Manager
+^^^^^^^^^^^^^^^^^^
+
+.. index:: single: window manager (widgets)
+
+.. % WindowMgr.html
+
+In Tk, there is a utility command, ``wm``, for interacting with the window
+manager. Options to the ``wm`` command allow you to control things like titles,
+placement, icon bitmaps, and the like. In :mod:`Tkinter`, these commands have
+been implemented as methods on the :class:`Wm` class. Toplevel widgets are
+subclassed from the :class:`Wm` class, and so can call the :class:`Wm` methods
+directly.
+
+To get at the toplevel window that contains a given widget, you can often just
+refer to the widget's master. Of course if the widget has been packed inside of
+a frame, the master won't represent a toplevel window. To get at the toplevel
+window that contains an arbitrary widget, you can call the :meth:`_root` method.
+This method begins with an underscore to denote the fact that this function is
+part of the implementation, and not an interface to Tk functionality.
+
+.. % See also \citetitle[classes/ClassWm.html]{the Wm class interface}.
+
+Here are some examples of typical usage::
+
+ from Tkinter import *
+ class App(Frame):
+ def __init__(self, master=None):
+ Frame.__init__(self, master)
+ self.pack()
+
+
+ # create the application
+ myapp = App()
+
+ #
+ # here are method calls to the window manager class
+ #
+ myapp.master.title("My Do-Nothing Application")
+ myapp.master.maxsize(1000, 400)
+
+ # start the program
+ myapp.mainloop()
+
+
+Tk Option Data Types
+^^^^^^^^^^^^^^^^^^^^
+
+.. index:: single: Tk Option Data Types
+
+.. % OptionTypes.html
+
+anchor
+ Legal values are points of the compass: ``"n"``, ``"ne"``, ``"e"``, ``"se"``,
+ ``"s"``, ``"sw"``, ``"w"``, ``"nw"``, and also ``"center"``.
+
+bitmap
+ There are eight built-in, named bitmaps: ``'error'``, ``'gray25'``,
+ ``'gray50'``, ``'hourglass'``, ``'info'``, ``'questhead'``, ``'question'``,
+ ``'warning'``. To specify an X bitmap filename, give the full path to the file,
+ preceded with an ``@``, as in ``"@/usr/contrib/bitmap/gumby.bit"``.
+
+boolean
+ You can pass integers 0 or 1 or the strings ``"yes"`` or ``"no"`` .
+
+callback
+ This is any Python function that takes no arguments. For example::
+
+ def print_it():
+ print "hi there"
+ fred["command"] = print_it
+
+color
+ Colors can be given as the names of X colors in the rgb.txt file, or as strings
+ representing RGB values in 4 bit: ``"#RGB"``, 8 bit: ``"#RRGGBB"``, 12 bit"
+ ``"#RRRGGGBBB"``, or 16 bit ``"#RRRRGGGGBBBB"`` ranges, where R,G,B here
+ represent any legal hex digit. See page 160 of Ousterhout's book for details.
+
+cursor
+ The standard X cursor names from :file:`cursorfont.h` can be used, without the
+ ``XC_`` prefix. For example to get a hand cursor (:const:`XC_hand2`), use the
+ string ``"hand2"``. You can also specify a bitmap and mask file of your own.
+ See page 179 of Ousterhout's book.
+
+distance
+ Screen distances can be specified in either pixels or absolute distances.
+ Pixels are given as numbers and absolute distances as strings, with the trailing
+ character denoting units: ``c`` for centimetres, ``i`` for inches, ``m`` for
+ millimetres, ``p`` for printer's points. For example, 3.5 inches is expressed
+ as ``"3.5i"``.
+
+font
+ Tk uses a list font name format, such as ``{courier 10 bold}``. Font sizes with
+ positive numbers are measured in points; sizes with negative numbers are
+ measured in pixels.
+
+geometry
+ This is a string of the form ``widthxheight``, where width and height are
+ measured in pixels for most widgets (in characters for widgets displaying text).
+ For example: ``fred["geometry"] = "200x100"``.
+
+justify
+ Legal values are the strings: ``"left"``, ``"center"``, ``"right"``, and
+ ``"fill"``.
+
+region
+ This is a string with four space-delimited elements, each of which is a legal
+ distance (see above). For example: ``"2 3 4 5"`` and ``"3i 2i 4.5i 2i"`` and
+ ``"3c 2c 4c 10.43c"`` are all legal regions.
+
+relief
+ Determines what the border style of a widget will be. Legal values are:
+ ``"raised"``, ``"sunken"``, ``"flat"``, ``"groove"``, and ``"ridge"``.
+
+scrollcommand
+ This is almost always the :meth:`set` method of some scrollbar widget, but can
+ be any widget method that takes a single argument. Refer to the file
+ :file:`Demo/tkinter/matt/canvas-with-scrollbars.py` in the Python source
+ distribution for an example.
+
+wrap:
+ Must be one of: ``"none"``, ``"char"``, or ``"word"``.
+
+
+Bindings and Events
+^^^^^^^^^^^^^^^^^^^
+
+.. index::
+ single: bind (widgets)
+ single: events (widgets)
+
+.. % Bindings.html
+
+The bind method from the widget command allows you to watch for certain events
+and to have a callback function trigger when that event type occurs. The form
+of the bind method is::
+
+ def bind(self, sequence, func, add=''):
+
+where:
+
+sequence
+ is a string that denotes the target kind of event. (See the bind man page and
+ page 201 of John Ousterhout's book for details).
+
+func
+ is a Python function, taking one argument, to be invoked when the event occurs.
+ An Event instance will be passed as the argument. (Functions deployed this way
+ are commonly known as *callbacks*.)
+
+add
+ is optional, either ``''`` or ``'+'``. Passing an empty string denotes that
+ this binding is to replace any other bindings that this event is associated
+ with. Passing a ``'+'`` means that this function is to be added to the list
+ of functions bound to this event type.
+
+For example::
+
+ def turnRed(self, event):
+ event.widget["activeforeground"] = "red"
+
+ self.button.bind("<Enter>", self.turnRed)
+
+Notice how the widget field of the event is being accessed in the
+:meth:`turnRed` callback. This field contains the widget that caught the X
+event. The following table lists the other event fields you can access, and how
+they are denoted in Tk, which can be useful when referring to the Tk man pages.
+::
+
+ Tk Tkinter Event Field Tk Tkinter Event Field
+ -- ------------------- -- -------------------
+ %f focus %A char
+ %h height %E send_event
+ %k keycode %K keysym
+ %s state %N keysym_num
+ %t time %T type
+ %w width %W widget
+ %x x %X x_root
+ %y y %Y y_root
+
+
+The index Parameter
+^^^^^^^^^^^^^^^^^^^
+
+A number of widgets require"index" parameters to be passed. These are used to
+point at a specific place in a Text widget, or to particular characters in an
+Entry widget, or to particular menu items in a Menu widget.
+
+.. % Index.html
+
+Entry widget indexes (index, view index, etc.)
+ Entry widgets have options that refer to character positions in the text being
+ displayed. You can use these :mod:`Tkinter` functions to access these special
+ points in text widgets:
+
+ AtEnd()
+ refers to the last position in the text
+
+ AtInsert()
+ refers to the point where the text cursor is
+
+ AtSelFirst()
+ indicates the beginning point of the selected text
+
+ AtSelLast()
+ denotes the last point of the selected text and finally
+
+ At(x[, y])
+ refers to the character at pixel location *x*, *y* (with *y* not used in the
+ case of a text entry widget, which contains a single line of text).
+
+Text widget indexes
+ The index notation for Text widgets is very rich and is best described in the Tk
+ man pages.
+
+Menu indexes (menu.invoke(), menu.entryconfig(), etc.)
+ Some options and methods for menus manipulate specific menu entries. Anytime a
+ menu index is needed for an option or a parameter, you may pass in:
+
+ * an integer which refers to the numeric position of the entry in the widget,
+ counted from the top, starting with 0;
+
+ * the string ``'active'``, which refers to the menu position that is currently
+ under the cursor;
+
+ * the string ``"last"`` which refers to the last menu item;
+
+ * An integer preceded by ``@``, as in ``@6``, where the integer is interpreted
+ as a y pixel coordinate in the menu's coordinate system;
+
+ * the string ``"none"``, which indicates no menu entry at all, most often used
+ with menu.activate() to deactivate all entries, and finally,
+
+ * a text string that is pattern matched against the label of the menu entry, as
+ scanned from the top of the menu to the bottom. Note that this index type is
+ considered after all the others, which means that matches for menu items
+ labelled ``last``, ``active``, or ``none`` may be interpreted as the above
+ literals, instead.
+
+
+Images
+^^^^^^
+
+Bitmap/Pixelmap images can be created through the subclasses of
+:class:`Tkinter.Image`:
+
+* :class:`BitmapImage` can be used for X11 bitmap data.
+
+* :class:`PhotoImage` can be used for GIF and PPM/PGM color bitmaps.
+
+Either type of image is created through either the ``file`` or the ``data``
+option (other options are available as well).
+
+The image object can then be used wherever an ``image`` option is supported by
+some widget (e.g. labels, buttons, menus). In these cases, Tk will not keep a
+reference to the image. When the last Python reference to the image object is
+deleted, the image data is deleted as well, and Tk will display an empty box
+wherever the image was used.
+
diff --git a/Doc/library/token.rst b/Doc/library/token.rst
new file mode 100644
index 0000000000..5bf0ea80e2
--- /dev/null
+++ b/Doc/library/token.rst
@@ -0,0 +1,47 @@
+
+:mod:`token` --- Constants used with Python parse trees
+=======================================================
+
+.. module:: token
+ :synopsis: Constants representing terminal nodes of the parse tree.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+This module provides constants which represent the numeric values of leaf nodes
+of the parse tree (terminal tokens). Refer to the file :file:`Grammar/Grammar`
+in the Python distribution for the definitions of the names in the context of
+the language grammar. The specific numeric values which the names map to may
+change between Python versions.
+
+This module also provides one data object and some functions. The functions
+mirror definitions in the Python C header files.
+
+
+.. data:: tok_name
+
+ Dictionary mapping the numeric values of the constants defined in this module
+ back to name strings, allowing more human-readable representation of parse trees
+ to be generated.
+
+
+.. function:: ISTERMINAL(x)
+
+ Return true for terminal token values.
+
+
+.. function:: ISNONTERMINAL(x)
+
+ Return true for non-terminal token values.
+
+
+.. function:: ISEOF(x)
+
+ Return true if *x* is the marker indicating the end of input.
+
+
+.. seealso::
+
+ Module :mod:`parser`
+ The second example for the :mod:`parser` module shows how to use the
+ :mod:`symbol` module.
+
diff --git a/Doc/library/tokenize.rst b/Doc/library/tokenize.rst
new file mode 100644
index 0000000000..61f2c4de85
--- /dev/null
+++ b/Doc/library/tokenize.rst
@@ -0,0 +1,122 @@
+
+:mod:`tokenize` --- Tokenizer for Python source
+===============================================
+
+.. module:: tokenize
+ :synopsis: Lexical scanner for Python source code.
+.. moduleauthor:: Ka Ping Yee
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`tokenize` module provides a lexical scanner for Python source code,
+implemented in Python. The scanner in this module returns comments as tokens as
+well, making it useful for implementing "pretty-printers," including colorizers
+for on-screen displays.
+
+The primary entry point is a generator:
+
+
+.. function:: generate_tokens(readline)
+
+ The :func:`generate_tokens` generator requires one argment, *readline*, which
+ must be a callable object which provides the same interface as the
+ :meth:`readline` method of built-in file objects (see section
+ :ref:`bltin-file-objects`). Each call to the function should return one line of
+ input as a string.
+
+ The generator produces 5-tuples with these members: the token type; the token
+ string; a 2-tuple ``(srow, scol)`` of ints specifying the row and column where
+ the token begins in the source; a 2-tuple ``(erow, ecol)`` of ints specifying
+ the row and column where the token ends in the source; and the line on which the
+ token was found. The line passed is the *logical* line; continuation lines are
+ included.
+
+ .. versionadded:: 2.2
+
+An older entry point is retained for backward compatibility:
+
+
+.. function:: tokenize(readline[, tokeneater])
+
+ The :func:`tokenize` function accepts two parameters: one representing the input
+ stream, and one providing an output mechanism for :func:`tokenize`.
+
+ The first parameter, *readline*, must be a callable object which provides the
+ same interface as the :meth:`readline` method of built-in file objects (see
+ section :ref:`bltin-file-objects`). Each call to the function should return one
+ line of input as a string. Alternately, *readline* may be a callable object that
+ signals completion by raising :exc:`StopIteration`.
+
+ .. versionchanged:: 2.5
+ Added :exc:`StopIteration` support.
+
+ The second parameter, *tokeneater*, must also be a callable object. It is
+ called once for each token, with five arguments, corresponding to the tuples
+ generated by :func:`generate_tokens`.
+
+All constants from the :mod:`token` module are also exported from
+:mod:`tokenize`, as are two additional token type values that might be passed to
+the *tokeneater* function by :func:`tokenize`:
+
+
+.. data:: COMMENT
+
+ Token value used to indicate a comment.
+
+
+.. data:: NL
+
+ Token value used to indicate a non-terminating newline. The NEWLINE token
+ indicates the end of a logical line of Python code; NL tokens are generated when
+ a logical line of code is continued over multiple physical lines.
+
+Another function is provided to reverse the tokenization process. This is useful
+for creating tools that tokenize a script, modify the token stream, and write
+back the modified script.
+
+
+.. function:: untokenize(iterable)
+
+ Converts tokens back into Python source code. The *iterable* must return
+ sequences with at least two elements, the token type and the token string. Any
+ additional sequence elements are ignored.
+
+ The reconstructed script is returned as a single string. The result is
+ guaranteed to tokenize back to match the input so that the conversion is
+ lossless and round-trips are assured. The guarantee applies only to the token
+ type and token string as the spacing between tokens (column positions) may
+ change.
+
+ .. versionadded:: 2.5
+
+Example of a script re-writer that transforms float literals into Decimal
+objects::
+
+ def decistmt(s):
+ """Substitute Decimals for floats in a string of statements.
+
+ >>> from decimal import Decimal
+ >>> s = 'print +21.3e-5*-.1234/81.7'
+ >>> decistmt(s)
+ "print +Decimal ('21.3e-5')*-Decimal ('.1234')/Decimal ('81.7')"
+
+ >>> exec(s)
+ -3.21716034272e-007
+ >>> exec(decistmt(s))
+ -3.217160342717258261933904529E-7
+
+ """
+ result = []
+ g = generate_tokens(StringIO(s).readline) # tokenize the string
+ for toknum, tokval, _, _, _ in g:
+ if toknum == NUMBER and '.' in tokval: # replace NUMBER tokens
+ result.extend([
+ (NAME, 'Decimal'),
+ (OP, '('),
+ (STRING, repr(tokval)),
+ (OP, ')')
+ ])
+ else:
+ result.append((toknum, tokval))
+ return untokenize(result)
+
diff --git a/Doc/library/trace.rst b/Doc/library/trace.rst
new file mode 100644
index 0000000000..91cf1a46c5
--- /dev/null
+++ b/Doc/library/trace.rst
@@ -0,0 +1,128 @@
+
+:mod:`trace` --- Trace or track Python statement execution
+==========================================================
+
+.. module:: trace
+ :synopsis: Trace or track Python statement execution.
+
+
+The :mod:`trace` module allows you to trace program execution, generate
+annotated statement coverage listings, print caller/callee relationships and
+list functions executed during a program run. It can be used in another program
+or from the command line.
+
+
+.. _trace-cli:
+
+Command Line Usage
+------------------
+
+The :mod:`trace` module can be invoked from the command line. It can be as
+simple as ::
+
+ python -m trace --count somefile.py ...
+
+The above will generate annotated listings of all Python modules imported during
+the execution of :file:`somefile.py`.
+
+The following command-line arguments are supported:
+
+:option:`--trace`, :option:`-t`
+ Display lines as they are executed.
+
+:option:`--count`, :option:`-c`
+ Produce a set of annotated listing files upon program completion that shows how
+ many times each statement was executed.
+
+:option:`--report`, :option:`-r`
+ Produce an annotated list from an earlier program run that used the
+ :option:`--count` and :option:`--file` arguments.
+
+:option:`--no-report`, :option:`-R`
+ Do not generate annotated listings. This is useful if you intend to make
+ several runs with :option:`--count` then produce a single set of annotated
+ listings at the end.
+
+:option:`--listfuncs`, :option:`-l`
+ List the functions executed by running the program.
+
+:option:`--trackcalls`, :option:`-T`
+ Generate calling relationships exposed by running the program.
+
+:option:`--file`, :option:`-f`
+ Name a file containing (or to contain) counts.
+
+:option:`--coverdir`, :option:`-C`
+ Name a directory in which to save annotated listing files.
+
+:option:`--missing`, :option:`-m`
+ When generating annotated listings, mark lines which were not executed with
+ '``>>>>>>``'.
+
+:option:`--summary`, :option:`-s`
+ When using :option:`--count` or :option:`--report`, write a brief summary to
+ stdout for each file processed.
+
+:option:`--ignore-module`
+ Ignore the named module and its submodules (if it is a package). May be given
+ multiple times.
+
+:option:`--ignore-dir`
+ Ignore all modules and packages in the named directory and subdirectories. May
+ be given multiple times.
+
+
+.. _trace-api:
+
+Programming Interface
+---------------------
+
+
+.. class:: Trace([count=1[, trace=1[, countfuncs=0[, countcallers=0[, ignoremods=()[, ignoredirs=()[, infile=None[, outfile=None]]]]]]]])
+
+ Create an object to trace execution of a single statement or expression. All
+ parameters are optional. *count* enables counting of line numbers. *trace*
+ enables line execution tracing. *countfuncs* enables listing of the functions
+ called during the run. *countcallers* enables call relationship tracking.
+ *ignoremods* is a list of modules or packages to ignore. *ignoredirs* is a list
+ of directories whose modules or packages should be ignored. *infile* is the
+ file from which to read stored count information. *outfile* is a file in which
+ to write updated count information.
+
+
+.. method:: Trace.run(cmd)
+
+ Run *cmd* under control of the Trace object with the current tracing parameters.
+
+
+.. method:: Trace.runctx(cmd[, globals=None[, locals=None]])
+
+ Run *cmd* under control of the Trace object with the current tracing parameters
+ in the defined global and local environments. If not defined, *globals* and
+ *locals* default to empty dictionaries.
+
+
+.. method:: Trace.runfunc(func, *args, **kwds)
+
+ Call *func* with the given arguments under control of the :class:`Trace` object
+ with the current tracing parameters.
+
+This is a simple example showing the use of this module::
+
+ import sys
+ import trace
+
+ # create a Trace object, telling it what to ignore, and whether to
+ # do tracing or line-counting or both.
+ tracer = trace.Trace(
+ ignoredirs=[sys.prefix, sys.exec_prefix],
+ trace=0,
+ count=1)
+
+ # run the new command using the given tracer
+ tracer.run('main()')
+
+ # make a report, placing output in /tmp
+ r = tracer.results()
+ r.write_results(show_missing=True, coverdir="/tmp")
+
diff --git a/Doc/library/traceback.rst b/Doc/library/traceback.rst
new file mode 100644
index 0000000000..ec8687fc7e
--- /dev/null
+++ b/Doc/library/traceback.rst
@@ -0,0 +1,160 @@
+
+:mod:`traceback` --- Print or retrieve a stack traceback
+========================================================
+
+.. module:: traceback
+ :synopsis: Print or retrieve a stack traceback.
+
+
+This module provides a standard interface to extract, format and print stack
+traces of Python programs. It exactly mimics the behavior of the Python
+interpreter when it prints a stack trace. This is useful when you want to print
+stack traces under program control, such as in a "wrapper" around the
+interpreter.
+
+.. index:: object: traceback
+
+The module uses traceback objects --- this is the object type that is stored in
+the ``sys.last_traceback`` variable and returned as the third item from
+:func:`sys.exc_info`.
+
+The module defines the following functions:
+
+
+.. function:: print_tb(traceback[, limit[, file]])
+
+ Print up to *limit* stack trace entries from *traceback*. If *limit* is omitted
+ or ``None``, all entries are printed. If *file* is omitted or ``None``, the
+ output goes to ``sys.stderr``; otherwise it should be an open file or file-like
+ object to receive the output.
+
+
+.. function:: print_exception(type, value, traceback[, limit[, file]])
+
+ Print exception information and up to *limit* stack trace entries from
+ *traceback* to *file*. This differs from :func:`print_tb` in the following ways:
+ (1) if *traceback* is not ``None``, it prints a header ``Traceback (most recent
+ call last):``; (2) it prints the exception *type* and *value* after the stack
+ trace; (3) if *type* is :exc:`SyntaxError` and *value* has the appropriate
+ format, it prints the line where the syntax error occurred with a caret
+ indicating the approximate position of the error.
+
+
+.. function:: print_exc([limit[, file]])
+
+ This is a shorthand for ``print_exception(*sys.exc_info()``.
+
+
+.. function:: format_exc([limit])
+
+ This is like ``print_exc(limit)`` but returns a string instead of printing to a
+ file.
+
+ .. versionadded:: 2.4
+
+
+.. function:: print_last([limit[, file]])
+
+ This is a shorthand for ``print_exception(sys.last_type, sys.last_value,
+ sys.last_traceback, limit, file)``.
+
+
+.. function:: print_stack([f[, limit[, file]]])
+
+ This function prints a stack trace from its invocation point. The optional *f*
+ argument can be used to specify an alternate stack frame to start. The optional
+ *limit* and *file* arguments have the same meaning as for
+ :func:`print_exception`.
+
+
+.. function:: extract_tb(traceback[, limit])
+
+ Return a list of up to *limit* "pre-processed" stack trace entries extracted
+ from the traceback object *traceback*. It is useful for alternate formatting of
+ stack traces. If *limit* is omitted or ``None``, all entries are extracted. A
+ "pre-processed" stack trace entry is a quadruple (*filename*, *line number*,
+ *function name*, *text*) representing the information that is usually printed
+ for a stack trace. The *text* is a string with leading and trailing whitespace
+ stripped; if the source is not available it is ``None``.
+
+
+.. function:: extract_stack([f[, limit]])
+
+ Extract the raw traceback from the current stack frame. The return value has
+ the same format as for :func:`extract_tb`. The optional *f* and *limit*
+ arguments have the same meaning as for :func:`print_stack`.
+
+
+.. function:: format_list(list)
+
+ Given a list of tuples as returned by :func:`extract_tb` or
+ :func:`extract_stack`, return a list of strings ready for printing. Each string
+ in the resulting list corresponds to the item with the same index in the
+ argument list. Each string ends in a newline; the strings may contain internal
+ newlines as well, for those items whose source text line is not ``None``.
+
+
+.. function:: format_exception_only(type, value)
+
+ Format the exception part of a traceback. The arguments are the exception type
+ and value such as given by ``sys.last_type`` and ``sys.last_value``. The return
+ value is a list of strings, each ending in a newline. Normally, the list
+ contains a single string; however, for :exc:`SyntaxError` exceptions, it
+ contains several lines that (when printed) display detailed information about
+ where the syntax error occurred. The message indicating which exception
+ occurred is the always last string in the list.
+
+
+.. function:: format_exception(type, value, tb[, limit])
+
+ Format a stack trace and the exception information. The arguments have the
+ same meaning as the corresponding arguments to :func:`print_exception`. The
+ return value is a list of strings, each ending in a newline and some containing
+ internal newlines. When these lines are concatenated and printed, exactly the
+ same text is printed as does :func:`print_exception`.
+
+
+.. function:: format_tb(tb[, limit])
+
+ A shorthand for ``format_list(extract_tb(tb, limit))``.
+
+
+.. function:: format_stack([f[, limit]])
+
+ A shorthand for ``format_list(extract_stack(f, limit))``.
+
+
+.. function:: tb_lineno(tb)
+
+ This function returns the current line number set in the traceback object. This
+ function was necessary because in versions of Python prior to 2.3 when the
+ :option:`-O` flag was passed to Python the ``tb.tb_lineno`` was not updated
+ correctly. This function has no use in versions past 2.3.
+
+
+.. _traceback-example:
+
+Traceback Example
+-----------------
+
+This simple example implements a basic read-eval-print loop, similar to (but
+less useful than) the standard Python interactive interpreter loop. For a more
+complete implementation of the interpreter loop, refer to the :mod:`code`
+module. ::
+
+ import sys, traceback
+
+ def run_user_code(envdir):
+ source = raw_input(">>> ")
+ try:
+ exec(source, envdir)
+ except:
+ print "Exception in user code:"
+ print '-'*60
+ traceback.print_exc(file=sys.stdout)
+ print '-'*60
+
+ envdir = {}
+ while 1:
+ run_user_code(envdir)
+
diff --git a/Doc/library/tty.rst b/Doc/library/tty.rst
new file mode 100644
index 0000000000..688faee4ab
--- /dev/null
+++ b/Doc/library/tty.rst
@@ -0,0 +1,38 @@
+
+:mod:`tty` --- Terminal control functions
+=========================================
+
+.. module:: tty
+ :platform: Unix
+ :synopsis: Utility functions that perform common terminal control operations.
+.. moduleauthor:: Steen Lumholt
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`tty` module defines functions for putting the tty into cbreak and raw
+modes.
+
+Because it requires the :mod:`termios` module, it will work only on Unix.
+
+The :mod:`tty` module defines the following functions:
+
+
+.. function:: setraw(fd[, when])
+
+ Change the mode of the file descriptor *fd* to raw. If *when* is omitted, it
+ defaults to :const:`termios.TCSAFLUSH`, and is passed to
+ :func:`termios.tcsetattr`.
+
+
+.. function:: setcbreak(fd[, when])
+
+ Change the mode of file descriptor *fd* to cbreak. If *when* is omitted, it
+ defaults to :const:`termios.TCSAFLUSH`, and is passed to
+ :func:`termios.tcsetattr`.
+
+
+.. seealso::
+
+ Module :mod:`termios`
+ Low-level terminal control interface.
+
diff --git a/Doc/library/turtle.rst b/Doc/library/turtle.rst
new file mode 100644
index 0000000000..354bb1114d
--- /dev/null
+++ b/Doc/library/turtle.rst
@@ -0,0 +1,312 @@
+
+:mod:`turtle` --- Turtle graphics for Tk
+========================================
+
+.. module:: turtle
+ :platform: Tk
+ :synopsis: An environment for turtle graphics.
+.. moduleauthor:: Guido van Rossum <guido@python.org>
+
+
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`turtle` module provides turtle graphics primitives, in both an
+object-oriented and procedure-oriented ways. Because it uses :mod:`Tkinter` for
+the underlying graphics, it needs a version of python installed with Tk support.
+
+The procedural interface uses a pen and a canvas which are automagically created
+when any of the functions are called.
+
+The :mod:`turtle` module defines the following functions:
+
+
+.. function:: degrees()
+
+ Set angle measurement units to degrees.
+
+
+.. function:: radians()
+
+ Set angle measurement units to radians.
+
+
+.. function:: setup(**kwargs)
+
+ Sets the size and position of the main window. Keywords are:
+
+ * ``width``: either a size in pixels or a fraction of the screen. The default is
+ 50% of the screen.
+
+ * ``height``: either a size in pixels or a fraction of the screen. The default
+ is 50% of the screen.
+
+ * ``startx``: starting position in pixels from the left edge of the screen.
+ ``None`` is the default value and centers the window horizontally on screen.
+
+ * ``starty``: starting position in pixels from the top edge of the screen.
+ ``None`` is the default value and centers the window vertically on screen.
+
+ Examples::
+
+ # Uses default geometry: 50% x 50% of screen, centered.
+ setup()
+
+ # Sets window to 200x200 pixels, in upper left of screen
+ setup (width=200, height=200, startx=0, starty=0)
+
+ # Sets window to 75% of screen by 50% of screen, and centers it.
+ setup(width=.75, height=0.5, startx=None, starty=None)
+
+
+.. function:: title(title_str)
+
+ Set the window's title to *title*.
+
+
+.. function:: done()
+
+ Enters the Tk main loop. The window will continue to be displayed until the
+ user closes it or the process is killed.
+
+
+.. function:: reset()
+
+ Clear the screen, re-center the pen, and set variables to the default values.
+
+
+.. function:: clear()
+
+ Clear the screen.
+
+
+.. function:: tracer(flag)
+
+ Set tracing on/off (according to whether flag is true or not). Tracing means
+ line are drawn more slowly, with an animation of an arrow along the line.
+
+
+.. function:: speed(speed)
+
+ Set the speed of the turtle. Valid values for the parameter *speed* are
+ ``'fastest'`` (no delay), ``'fast'``, (delay 5ms), ``'normal'`` (delay 10ms),
+ ``'slow'`` (delay 15ms), and ``'slowest'`` (delay 20ms).
+
+ .. versionadded:: 2.5
+
+
+.. function:: delay(delay)
+
+ Set the speed of the turtle to *delay*, which is given in ms.
+
+ .. versionadded:: 2.5
+
+
+.. function:: forward(distance)
+
+ Go forward *distance* steps.
+
+
+.. function:: backward(distance)
+
+ Go backward *distance* steps.
+
+
+.. function:: left(angle)
+
+ Turn left *angle* units. Units are by default degrees, but can be set via the
+ :func:`degrees` and :func:`radians` functions.
+
+
+.. function:: right(angle)
+
+ Turn right *angle* units. Units are by default degrees, but can be set via the
+ :func:`degrees` and :func:`radians` functions.
+
+
+.. function:: up()
+
+ Move the pen up --- stop drawing.
+
+
+.. function:: down()
+
+ Move the pen down --- draw when moving.
+
+
+.. function:: width(width)
+
+ Set the line width to *width*.
+
+
+.. function:: color(s)
+ color((r, g, b))
+ color(r, g, b)
+
+ Set the pen color. In the first form, the color is specified as a Tk color
+ specification as a string. The second form specifies the color as a tuple of
+ the RGB values, each in the range [0..1]. For the third form, the color is
+ specified giving the RGB values as three separate parameters (each in the range
+ [0..1]).
+
+
+.. function:: write(text[, move])
+
+ Write *text* at the current pen position. If *move* is true, the pen is moved to
+ the bottom-right corner of the text. By default, *move* is false.
+
+
+.. function:: fill(flag)
+
+ The complete specifications are rather complex, but the recommended usage is:
+ call ``fill(1)`` before drawing a path you want to fill, and call ``fill(0)``
+ when you finish to draw the path.
+
+
+.. function:: begin_fill()
+
+ Switch turtle into filling mode; Must eventually be followed by a corresponding
+ end_fill() call. Otherwise it will be ignored.
+
+ .. versionadded:: 2.5
+
+
+.. function:: end_fill()
+
+ End filling mode, and fill the shape; equivalent to ``fill(0)``.
+
+ .. versionadded:: 2.5
+
+
+.. function:: circle(radius[, extent])
+
+ Draw a circle with radius *radius* whose center-point is *radius* units left of
+ the turtle. *extent* determines which part of a circle is drawn: if not given it
+ defaults to a full circle.
+
+ If *extent* is not a full circle, one endpoint of the arc is the current pen
+ position. The arc is drawn in a counter clockwise direction if *radius* is
+ positive, otherwise in a clockwise direction. In the process, the direction of
+ the turtle is changed by the amount of the *extent*.
+
+
+.. function:: goto(x, y)
+ goto((x, y))
+
+ Go to co-ordinates *x*, *y*. The co-ordinates may be specified either as two
+ separate arguments or as a 2-tuple.
+
+
+.. function:: towards(x, y)
+
+ Return the angle of the line from the turtle's position to the point *x*, *y*.
+ The co-ordinates may be specified either as two separate arguments, as a
+ 2-tuple, or as another pen object.
+
+ .. versionadded:: 2.5
+
+
+.. function:: heading()
+
+ Return the current orientation of the turtle.
+
+ .. versionadded:: 2.3
+
+
+.. function:: setheading(angle)
+
+ Set the orientation of the turtle to *angle*.
+
+ .. versionadded:: 2.3
+
+
+.. function:: position()
+
+ Return the current location of the turtle as an ``(x,y)`` pair.
+
+ .. versionadded:: 2.3
+
+
+.. function:: setx(x)
+
+ Set the x coordinate of the turtle to *x*.
+
+ .. versionadded:: 2.3
+
+
+.. function:: sety(y)
+
+ Set the y coordinate of the turtle to *y*.
+
+ .. versionadded:: 2.3
+
+
+.. function:: window_width()
+
+ Return the width of the canvas window.
+
+ .. versionadded:: 2.3
+
+
+.. function:: window_height()
+
+ Return the height of the canvas window.
+
+ .. versionadded:: 2.3
+
+This module also does ``from math import *``, so see the documentation for the
+:mod:`math` module for additional constants and functions useful for turtle
+graphics.
+
+
+.. function:: demo()
+
+ Exercise the module a bit.
+
+
+.. exception:: Error
+
+ Exception raised on any error caught by this module.
+
+For examples, see the code of the :func:`demo` function.
+
+This module defines the following classes:
+
+
+.. class:: Pen()
+
+ Define a pen. All above functions can be called as a methods on the given pen.
+ The constructor automatically creates a canvas do be drawn on.
+
+
+.. class:: Turtle()
+
+ Define a pen. This is essentially a synonym for ``Pen()``; :class:`Turtle` is an
+ empty subclass of :class:`Pen`.
+
+
+.. class:: RawPen(canvas)
+
+ Define a pen which draws on a canvas *canvas*. This is useful if you want to
+ use the module to create graphics in a "real" program.
+
+
+.. _pen-rawpen-objects:
+
+Turtle, Pen and RawPen Objects
+------------------------------
+
+Most of the global functions available in the module are also available as
+methods of the :class:`Turtle`, :class:`Pen` and :class:`RawPen` classes,
+affecting only the state of the given pen.
+
+The only method which is more powerful as a method is :func:`degrees`, which
+takes an optional argument letting you specify the number of units
+corresponding to a full circle:
+
+
+.. method:: Turtle.degrees([fullcircle])
+
+ *fullcircle* is by default 360. This can cause the pen to have any angular units
+ whatever: give *fullcircle* 2\*$π for radians, or 400 for gradians.
+
diff --git a/Doc/library/types.rst b/Doc/library/types.rst
new file mode 100644
index 0000000000..c636a73b0f
--- /dev/null
+++ b/Doc/library/types.rst
@@ -0,0 +1,257 @@
+
+:mod:`types` --- Names for built-in types
+=========================================
+
+.. module:: types
+ :synopsis: Names for built-in types.
+
+
+This module defines names for some object types that are used by the standard
+Python interpreter, but not for the types defined by various extension modules.
+Also, it does not include some of the types that arise during processing such as
+the ``listiterator`` type. It is safe to use ``from types import *`` --- the
+module does not export any names besides the ones listed here. New names
+exported by future versions of this module will all end in ``Type``.
+
+Typical use is for functions that do different things depending on their
+argument types, like the following::
+
+ from types import *
+ def delete(mylist, item):
+ if type(item) is IntType:
+ del mylist[item]
+ else:
+ mylist.remove(item)
+
+Starting in Python 2.2, built-in factory functions such as :func:`int` and
+:func:`str` are also names for the corresponding types. This is now the
+preferred way to access the type instead of using the :mod:`types` module.
+Accordingly, the example above should be written as follows::
+
+ def delete(mylist, item):
+ if isinstance(item, int):
+ del mylist[item]
+ else:
+ mylist.remove(item)
+
+The module defines the following names:
+
+
+.. data:: NoneType
+
+ The type of ``None``.
+
+
+.. data:: TypeType
+
+ .. index:: builtin: type
+
+ The type of type objects (such as returned by :func:`type`); alias of the
+ built-in :class:`type`.
+
+
+.. data:: BooleanType
+
+ The type of the :class:`bool` values ``True`` and ``False``; alias of the
+ built-in :class:`bool`.
+
+ .. versionadded:: 2.3
+
+
+.. data:: IntType
+
+ The type of integers (e.g. ``1``); alias of the built-in :class:`int`.
+
+
+.. data:: LongType
+
+ The type of long integers (e.g. ``1L``); alias of the built-in :class:`long`.
+
+
+.. data:: FloatType
+
+ The type of floating point numbers (e.g. ``1.0``); alias of the built-in
+ :class:`float`.
+
+
+.. data:: ComplexType
+
+ The type of complex numbers (e.g. ``1.0j``). This is not defined if Python was
+ built without complex number support.
+
+
+.. data:: StringType
+
+ The type of character strings (e.g. ``'Spam'``); alias of the built-in
+ :class:`str`.
+
+
+.. data:: UnicodeType
+
+ The type of Unicode character strings (e.g. ``u'Spam'``). This is not defined
+ if Python was built without Unicode support. It's an alias of the built-in
+ :class:`unicode`.
+
+
+.. data:: TupleType
+
+ The type of tuples (e.g. ``(1, 2, 3, 'Spam')``); alias of the built-in
+ :class:`tuple`.
+
+
+.. data:: ListType
+
+ The type of lists (e.g. ``[0, 1, 2, 3]``); alias of the built-in
+ :class:`list`.
+
+
+.. data:: DictType
+
+ The type of dictionaries (e.g. ``{'Bacon': 1, 'Ham': 0}``); alias of the
+ built-in :class:`dict`.
+
+
+.. data:: DictionaryType
+
+ An alternate name for ``DictType``.
+
+
+.. data:: FunctionType
+
+ The type of user-defined functions and lambdas.
+
+
+.. data:: LambdaType
+
+ An alternate name for ``FunctionType``.
+
+
+.. data:: GeneratorType
+
+ The type of generator-iterator objects, produced by calling a generator
+ function.
+
+ .. versionadded:: 2.2
+
+
+.. data:: CodeType
+
+ .. index:: builtin: compile
+
+ The type for code objects such as returned by :func:`compile`.
+
+
+.. data:: ClassType
+
+ The type of user-defined classes.
+
+
+.. data:: MethodType
+
+ The type of methods of user-defined class instances.
+
+
+.. data:: UnboundMethodType
+
+ An alternate name for ``MethodType``.
+
+
+.. data:: BuiltinFunctionType
+
+ The type of built-in functions like :func:`len` or :func:`sys.exit`.
+
+
+.. data:: BuiltinMethodType
+
+ An alternate name for ``BuiltinFunction``.
+
+
+.. data:: ModuleType
+
+ The type of modules.
+
+
+.. data:: FileType
+
+ The type of open file objects such as ``sys.stdout``; alias of the built-in
+ :class:`file`.
+
+
+.. data:: RangeType
+
+ .. index:: builtin: range
+
+ The type of range objects returned by :func:`range`; alias of the built-in
+ :class:`range`.
+
+
+.. data:: SliceType
+
+ .. index:: builtin: slice
+
+ The type of objects returned by :func:`slice`; alias of the built-in
+ :class:`slice`.
+
+
+.. data:: EllipsisType
+
+ The type of ``Ellipsis``.
+
+
+.. data:: TracebackType
+
+ The type of traceback objects such as found in ``sys.exc_info()[2]``.
+
+
+.. data:: FrameType
+
+ The type of frame objects such as found in ``tb.tb_frame`` if ``tb`` is a
+ traceback object.
+
+
+.. data:: BufferType
+
+ .. index:: builtin: buffer
+
+ The type of buffer objects created by the :func:`buffer` function.
+
+
+.. data:: DictProxyType
+
+ The type of dict proxies, such as ``TypeType.__dict__``.
+
+
+.. data:: NotImplementedType
+
+ The type of ``NotImplemented``
+
+
+.. data:: GetSetDescriptorType
+
+ The type of objects defined in extension modules with ``PyGetSetDef``, such as
+ ``FrameType.f_locals`` or ``array.array.typecode``. This constant is not
+ defined in implementations of Python that do not have such extension types, so
+ for portable code use ``hasattr(types, 'GetSetDescriptorType')``.
+
+ .. versionadded:: 2.5
+
+
+.. data:: MemberDescriptorType
+
+ The type of objects defined in extension modules with ``PyMemberDef``, such as
+ ``datetime.timedelta.days``. This constant is not defined in implementations of
+ Python that do not have such extension types, so for portable code use
+ ``hasattr(types, 'MemberDescriptorType')``.
+
+ .. versionadded:: 2.5
+
+
+.. data:: StringTypes
+
+ A sequence containing ``StringType`` and ``UnicodeType`` used to facilitate
+ easier checking for any string object. Using this is more portable than using a
+ sequence of the two string types constructed elsewhere since it only contains
+ ``UnicodeType`` if it has been built in the running version of Python. For
+ example: ``isinstance(s, types.StringTypes)``.
+
+ .. versionadded:: 2.2
diff --git a/Doc/library/undoc.rst b/Doc/library/undoc.rst
new file mode 100644
index 0000000000..ad46fc8027
--- /dev/null
+++ b/Doc/library/undoc.rst
@@ -0,0 +1,186 @@
+
+.. _undoc:
+
+********************
+Undocumented Modules
+********************
+
+Here's a quick listing of modules that are currently undocumented, but that
+should be documented. Feel free to contribute documentation for them! (Send
+via email to docs@python.org.)
+
+The idea and original contents for this chapter were taken from a posting by
+Fredrik Lundh; the specific contents of this chapter have been substantially
+revised.
+
+
+Miscellaneous useful utilities
+==============================
+
+Some of these are very old and/or not very robust; marked with "hmm."
+
+:mod:`bdb`
+ --- A generic Python debugger base class (used by pdb).
+
+:mod:`ihooks`
+ --- Import hook support (for :mod:`rexec`; may become obsolete).
+
+
+Platform specific modules
+=========================
+
+These modules are used to implement the :mod:`os.path` module, and are not
+documented beyond this mention. There's little need to document these.
+
+:mod:`ntpath`
+ --- Implementation of :mod:`os.path` on Win32, Win64, WinCE, and OS/2 platforms.
+
+:mod:`posixpath`
+ --- Implementation of :mod:`os.path` on POSIX.
+
+
+Multimedia
+==========
+
+:mod:`linuxaudiodev`
+ --- Play audio data on the Linux audio device. Replaced in Python 2.3 by the
+ :mod:`ossaudiodev` module.
+
+:mod:`sunaudio`
+ --- Interpret Sun audio headers (may become obsolete or a tool/demo).
+
+
+.. _undoc-mac-modules:
+
+Undocumented Mac OS modules
+===========================
+
+
+:mod:`applesingle` --- AppleSingle decoder
+------------------------------------------
+
+.. module:: applesingle
+ :platform: Mac
+ :synopsis: Rudimentary decoder for AppleSingle format files.
+
+
+
+:mod:`buildtools` --- Helper module for BuildApplet and Friends
+---------------------------------------------------------------
+
+.. module:: buildtools
+ :platform: Mac
+ :synopsis: Helper module for BuildApplet, BuildApplication and macfreeze.
+
+
+.. deprecated:: 2.4
+
+
+:mod:`icopen` --- Internet Config replacement for :meth:`open`
+--------------------------------------------------------------
+
+.. module:: icopen
+ :platform: Mac
+ :synopsis: Internet Config replacement for open().
+
+
+Importing :mod:`icopen` will replace the builtin :meth:`open` with a version
+that uses Internet Config to set file type and creator for new files.
+
+
+:mod:`macerrors` --- Mac OS Errors
+----------------------------------
+
+.. module:: macerrors
+ :platform: Mac
+ :synopsis: Constant definitions for many Mac OS error codes.
+
+
+:mod:`macerrors` contains constant definitions for many Mac OS error codes.
+
+
+:mod:`macresource` --- Locate script resources
+----------------------------------------------
+
+.. module:: macresource
+ :platform: Mac
+ :synopsis: Locate script resources.
+
+
+:mod:`macresource` helps scripts finding their resources, such as dialogs and
+menus, without requiring special case code for when the script is run under
+MacPython, as a MacPython applet or under OSX Python.
+
+
+:mod:`Nav` --- NavServices calls
+--------------------------------
+
+.. module:: Nav
+ :platform: Mac
+ :synopsis: Interface to Navigation Services.
+
+
+A low-level interface to Navigation Services.
+
+
+:mod:`PixMapWrapper` --- Wrapper for PixMap objects
+---------------------------------------------------
+
+.. module:: PixMapWrapper
+ :platform: Mac
+ :synopsis: Wrapper for PixMap objects.
+
+
+:mod:`PixMapWrapper` wraps a PixMap object with a Python object that allows
+access to the fields by name. It also has methods to convert to and from
+:mod:`PIL` images.
+
+
+:mod:`videoreader` --- Read QuickTime movies
+--------------------------------------------
+
+.. module:: videoreader
+ :platform: Mac
+ :synopsis: Read QuickTime movies frame by frame for further processing.
+
+
+:mod:`videoreader` reads and decodes QuickTime movies and passes a stream of
+images to your program. It also provides some support for audio tracks.
+
+
+:mod:`W` --- Widgets built on :mod:`FrameWork`
+----------------------------------------------
+
+.. module:: W
+ :platform: Mac
+ :synopsis: Widgets for the Mac, built on top of FrameWork.
+
+
+The :mod:`W` widgets are used extensively in the :program:`IDE`.
+
+
+.. _obsolete-modules:
+
+Obsolete
+========
+
+These modules are not normally available for import; additional work must be
+done to make them available.
+
+These extension modules written in C are not built by default. Under Unix, these
+must be enabled by uncommenting the appropriate lines in :file:`Modules/Setup`
+in the build tree and either rebuilding Python if the modules are statically
+linked, or building and installing the shared object if using dynamically-loaded
+extensions.
+
+.. % %% lib-old is empty as of Python 2.5
+.. % Those which are written in Python will be installed into the directory
+.. % \file{lib-old/} installed as part of the standard library. To use
+.. % these, the directory must be added to \code{sys.path}, possibly using
+.. % \envvar{PYTHONPATH}.
+
+.. % XXX need Windows instructions!
+
+
+ --- This section should be empty for Python 3.0.
+
diff --git a/Doc/library/unicodedata.rst b/Doc/library/unicodedata.rst
new file mode 100644
index 0000000000..017d4ee785
--- /dev/null
+++ b/Doc/library/unicodedata.rst
@@ -0,0 +1,165 @@
+
+:mod:`unicodedata` --- Unicode Database
+=======================================
+
+.. module:: unicodedata
+ :synopsis: Access the Unicode Database.
+.. moduleauthor:: Marc-Andre Lemburg <mal@lemburg.com>
+.. sectionauthor:: Marc-Andre Lemburg <mal@lemburg.com>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. index::
+ single: Unicode
+ single: character
+ pair: Unicode; database
+
+This module provides access to the Unicode Character Database which defines
+character properties for all Unicode characters. The data in this database is
+based on the :file:`UnicodeData.txt` file version 4.1.0 which is publicly
+available from ftp://ftp.unicode.org/.
+
+The module uses the same names and symbols as defined by the UnicodeData File
+Format 4.1.0 (see http://www.unicode.org/Public/4.1.0/ucd/UCD.html). It defines
+the following functions:
+
+
+.. function:: lookup(name)
+
+ Look up character by name. If a character with the given name is found, return
+ the corresponding Unicode character. If not found, :exc:`KeyError` is raised.
+
+
+.. function:: name(unichr[, default])
+
+ Returns the name assigned to the Unicode character *unichr* as a string. If no
+ name is defined, *default* is returned, or, if not given, :exc:`ValueError` is
+ raised.
+
+
+.. function:: decimal(unichr[, default])
+
+ Returns the decimal value assigned to the Unicode character *unichr* as integer.
+ If no such value is defined, *default* is returned, or, if not given,
+ :exc:`ValueError` is raised.
+
+
+.. function:: digit(unichr[, default])
+
+ Returns the digit value assigned to the Unicode character *unichr* as integer.
+ If no such value is defined, *default* is returned, or, if not given,
+ :exc:`ValueError` is raised.
+
+
+.. function:: numeric(unichr[, default])
+
+ Returns the numeric value assigned to the Unicode character *unichr* as float.
+ If no such value is defined, *default* is returned, or, if not given,
+ :exc:`ValueError` is raised.
+
+
+.. function:: category(unichr)
+
+ Returns the general category assigned to the Unicode character *unichr* as
+ string.
+
+
+.. function:: bidirectional(unichr)
+
+ Returns the bidirectional category assigned to the Unicode character *unichr* as
+ string. If no such value is defined, an empty string is returned.
+
+
+.. function:: combining(unichr)
+
+ Returns the canonical combining class assigned to the Unicode character *unichr*
+ as integer. Returns ``0`` if no combining class is defined.
+
+
+.. function:: east_asian_width(unichr)
+
+ Returns the east asian width assigned to the Unicode character *unichr* as
+ string.
+
+ .. versionadded:: 2.4
+
+
+.. function:: mirrored(unichr)
+
+ Returns the mirrored property assigned to the Unicode character *unichr* as
+ integer. Returns ``1`` if the character has been identified as a "mirrored"
+ character in bidirectional text, ``0`` otherwise.
+
+
+.. function:: decomposition(unichr)
+
+ Returns the character decomposition mapping assigned to the Unicode character
+ *unichr* as string. An empty string is returned in case no such mapping is
+ defined.
+
+
+.. function:: normalize(form, unistr)
+
+ Return the normal form *form* for the Unicode string *unistr*. Valid values for
+ *form* are 'NFC', 'NFKC', 'NFD', and 'NFKD'.
+
+ The Unicode standard defines various normalization forms of a Unicode string,
+ based on the definition of canonical equivalence and compatibility equivalence.
+ In Unicode, several characters can be expressed in various way. For example, the
+ character U+00C7 (LATIN CAPITAL LETTER C WITH CEDILLA) can also be expressed as
+ the sequence U+0043 (LATIN CAPITAL LETTER C) U+0327 (COMBINING CEDILLA).
+
+ For each character, there are two normal forms: normal form C and normal form D.
+ Normal form D (NFD) is also known as canonical decomposition, and translates
+ each character into its decomposed form. Normal form C (NFC) first applies a
+ canonical decomposition, then composes pre-combined characters again.
+
+ In addition to these two forms, there are two additional normal forms based on
+ compatibility equivalence. In Unicode, certain characters are supported which
+ normally would be unified with other characters. For example, U+2160 (ROMAN
+ NUMERAL ONE) is really the same thing as U+0049 (LATIN CAPITAL LETTER I).
+ However, it is supported in Unicode for compatibility with existing character
+ sets (e.g. gb2312).
+
+ The normal form KD (NFKD) will apply the compatibility decomposition, i.e.
+ replace all compatibility characters with their equivalents. The normal form KC
+ (NFKC) first applies the compatibility decomposition, followed by the canonical
+ composition.
+
+ .. versionadded:: 2.3
+
+In addition, the module exposes the following constant:
+
+
+.. data:: unidata_version
+
+ The version of the Unicode database used in this module.
+
+ .. versionadded:: 2.3
+
+
+.. data:: ucd_3_2_0
+
+ This is an object that has the same methods as the entire module, but uses the
+ Unicode database version 3.2 instead, for applications that require this
+ specific version of the Unicode database (such as IDNA).
+
+ .. versionadded:: 2.5
+
+Examples::
+
+ >>> unicodedata.lookup('LEFT CURLY BRACKET')
+ u'{'
+ >>> unicodedata.name(u'/')
+ 'SOLIDUS'
+ >>> unicodedata.decimal(u'9')
+ 9
+ >>> unicodedata.decimal(u'a')
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: not a decimal
+ >>> unicodedata.category(u'A') # 'L'etter, 'u'ppercase
+ 'Lu'
+ >>> unicodedata.bidirectional(u'\u0660') # 'A'rabic, 'N'umber
+ 'AN'
+
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
new file mode 100644
index 0000000000..3d3727fe94
--- /dev/null
+++ b/Doc/library/unittest.rst
@@ -0,0 +1,936 @@
+
+:mod:`unittest` --- Unit testing framework
+==========================================
+
+.. module:: unittest
+ :synopsis: Unit testing framework for Python.
+.. moduleauthor:: Steve Purcell <stephen_purcell@yahoo.com>
+.. sectionauthor:: Steve Purcell <stephen_purcell@yahoo.com>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Raymond Hettinger <python@rcn.com>
+
+
+.. versionadded:: 2.1
+
+The Python unit testing framework, sometimes referred to as "PyUnit," is a
+Python language version of JUnit, by Kent Beck and Erich Gamma. JUnit is, in
+turn, a Java version of Kent's Smalltalk testing framework. Each is the de
+facto standard unit testing framework for its respective language.
+
+:mod:`unittest` supports test automation, sharing of setup and shutdown code for
+tests, aggregation of tests into collections, and independence of the tests from
+the reporting framework. The :mod:`unittest` module provides classes that make
+it easy to support these qualities for a set of tests.
+
+To achieve this, :mod:`unittest` supports some important concepts:
+
+test fixture
+ A :dfn:`test fixture` represents the preparation needed to perform one or more
+ tests, and any associate cleanup actions. This may involve, for example,
+ creating temporary or proxy databases, directories, or starting a server
+ process.
+
+test case
+ A :dfn:`test case` is the smallest unit of testing. It checks for a specific
+ response to a particular set of inputs. :mod:`unittest` provides a base class,
+ :class:`TestCase`, which may be used to create new test cases.
+
+test suite
+ A :dfn:`test suite` is a collection of test cases, test suites, or both. It is
+ used to aggregate tests that should be executed together.
+
+test runner
+ A :dfn:`test runner` is a component which orchestrates the execution of tests
+ and provides the outcome to the user. The runner may use a graphical interface,
+ a textual interface, or return a special value to indicate the results of
+ executing the tests.
+
+The test case and test fixture concepts are supported through the
+:class:`TestCase` and :class:`FunctionTestCase` classes; the former should be
+used when creating new tests, and the latter can be used when integrating
+existing test code with a :mod:`unittest`\ -driven framework. When building test
+fixtures using :class:`TestCase`, the :meth:`setUp` and :meth:`tearDown` methods
+can be overridden to provide initialization and cleanup for the fixture. With
+:class:`FunctionTestCase`, existing functions can be passed to the constructor
+for these purposes. When the test is run, the fixture initialization is run
+first; if it succeeds, the cleanup method is run after the test has been
+executed, regardless of the outcome of the test. Each instance of the
+:class:`TestCase` will only be used to run a single test method, so a new
+fixture is created for each test.
+
+Test suites are implemented by the :class:`TestSuite` class. This class allows
+individual tests and test suites to be aggregated; when the suite is executed,
+all tests added directly to the suite and in "child" test suites are run.
+
+A test runner is an object that provides a single method, :meth:`run`, which
+accepts a :class:`TestCase` or :class:`TestSuite` object as a parameter, and
+returns a result object. The class :class:`TestResult` is provided for use as
+the result object. :mod:`unittest` provides the :class:`TextTestRunner` as an
+example test runner which reports test results on the standard error stream by
+default. Alternate runners can be implemented for other environments (such as
+graphical environments) without any need to derive from a specific class.
+
+
+.. seealso::
+
+ Module :mod:`doctest`
+ Another test-support module with a very different flavor.
+
+ `Simple Smalltalk Testing: With Patterns <http://www.XProgramming.com/testfram.htm>`_
+ Kent Beck's original paper on testing frameworks using the pattern shared by
+ :mod:`unittest`.
+
+
+.. _unittest-minimal-example:
+
+Basic example
+-------------
+
+The :mod:`unittest` module provides a rich set of tools for constructing and
+running tests. This section demonstrates that a small subset of the tools
+suffice to meet the needs of most users.
+
+Here is a short script to test three functions from the :mod:`random` module::
+
+ import random
+ import unittest
+
+ class TestSequenceFunctions(unittest.TestCase):
+
+ def setUp(self):
+ self.seq = range(10)
+
+ def testshuffle(self):
+ # make sure the shuffled sequence does not lose any elements
+ random.shuffle(self.seq)
+ self.seq.sort()
+ self.assertEqual(self.seq, range(10))
+
+ def testchoice(self):
+ element = random.choice(self.seq)
+ self.assert_(element in self.seq)
+
+ def testsample(self):
+ self.assertRaises(ValueError, random.sample, self.seq, 20)
+ for element in random.sample(self.seq, 5):
+ self.assert_(element in self.seq)
+
+ if __name__ == '__main__':
+ unittest.main()
+
+A testcase is created by subclassing :class:`unittest.TestCase`. The three
+individual tests are defined with methods whose names start with the letters
+``test``. This naming convention informs the test runner about which methods
+represent tests.
+
+The crux of each test is a call to :meth:`assertEqual` to check for an expected
+result; :meth:`assert_` to verify a condition; or :meth:`assertRaises` to verify
+that an expected exception gets raised. These methods are used instead of the
+:keyword:`assert` statement so the test runner can accumulate all test results
+and produce a report.
+
+When a :meth:`setUp` method is defined, the test runner will run that method
+prior to each test. Likewise, if a :meth:`tearDown` method is defined, the test
+runner will invoke that method after each test. In the example, :meth:`setUp`
+was used to create a fresh sequence for each test.
+
+The final block shows a simple way to run the tests. :func:`unittest.main`
+provides a command line interface to the test script. When run from the command
+line, the above script produces an output that looks like this::
+
+ ...
+ ----------------------------------------------------------------------
+ Ran 3 tests in 0.000s
+
+ OK
+
+Instead of :func:`unittest.main`, there are other ways to run the tests with a
+finer level of control, less terse output, and no requirement to be run from the
+command line. For example, the last two lines may be replaced with::
+
+ suite = unittest.TestLoader().loadTestsFromTestCase(TestSequenceFunctions)
+ unittest.TextTestRunner(verbosity=2).run(suite)
+
+Running the revised script from the interpreter or another script produces the
+following output::
+
+ testchoice (__main__.TestSequenceFunctions) ... ok
+ testsample (__main__.TestSequenceFunctions) ... ok
+ testshuffle (__main__.TestSequenceFunctions) ... ok
+
+ ----------------------------------------------------------------------
+ Ran 3 tests in 0.110s
+
+ OK
+
+The above examples show the most commonly used :mod:`unittest` features which
+are sufficient to meet many everyday testing needs. The remainder of the
+documentation explores the full feature set from first principles.
+
+
+.. _organizing-tests:
+
+Organizing test code
+--------------------
+
+The basic building blocks of unit testing are :dfn:`test cases` --- single
+scenarios that must be set up and checked for correctness. In :mod:`unittest`,
+test cases are represented by instances of :mod:`unittest`'s :class:`TestCase`
+class. To make your own test cases you must write subclasses of
+:class:`TestCase`, or use :class:`FunctionTestCase`.
+
+An instance of a :class:`TestCase`\ -derived class is an object that can
+completely run a single test method, together with optional set-up and tidy-up
+code.
+
+The testing code of a :class:`TestCase` instance should be entirely self
+contained, such that it can be run either in isolation or in arbitrary
+combination with any number of other test cases.
+
+The simplest :class:`TestCase` subclass will simply override the :meth:`runTest`
+method in order to perform specific testing code::
+
+ import unittest
+
+ class DefaultWidgetSizeTestCase(unittest.TestCase):
+ def runTest(self):
+ widget = Widget('The widget')
+ self.assertEqual(widget.size(), (50, 50), 'incorrect default size')
+
+Note that in order to test something, we use the one of the :meth:`assert\*` or
+:meth:`fail\*` methods provided by the :class:`TestCase` base class. If the
+test fails, an exception will be raised, and :mod:`unittest` will identify the
+test case as a :dfn:`failure`. Any other exceptions will be treated as
+:dfn:`errors`. This helps you identify where the problem is: :dfn:`failures` are
+caused by incorrect results - a 5 where you expected a 6. :dfn:`Errors` are
+caused by incorrect code - e.g., a :exc:`TypeError` caused by an incorrect
+function call.
+
+The way to run a test case will be described later. For now, note that to
+construct an instance of such a test case, we call its constructor without
+arguments::
+
+ testCase = DefaultWidgetSizeTestCase()
+
+Now, such test cases can be numerous, and their set-up can be repetitive. In
+the above case, constructing a :class:`Widget` in each of 100 Widget test case
+subclasses would mean unsightly duplication.
+
+Luckily, we can factor out such set-up code by implementing a method called
+:meth:`setUp`, which the testing framework will automatically call for us when
+we run the test::
+
+ import unittest
+
+ class SimpleWidgetTestCase(unittest.TestCase):
+ def setUp(self):
+ self.widget = Widget('The widget')
+
+ class DefaultWidgetSizeTestCase(SimpleWidgetTestCase):
+ def runTest(self):
+ self.failUnless(self.widget.size() == (50,50),
+ 'incorrect default size')
+
+ class WidgetResizeTestCase(SimpleWidgetTestCase):
+ def runTest(self):
+ self.widget.resize(100,150)
+ self.failUnless(self.widget.size() == (100,150),
+ 'wrong size after resize')
+
+If the :meth:`setUp` method raises an exception while the test is running, the
+framework will consider the test to have suffered an error, and the
+:meth:`runTest` method will not be executed.
+
+Similarly, we can provide a :meth:`tearDown` method that tidies up after the
+:meth:`runTest` method has been run::
+
+ import unittest
+
+ class SimpleWidgetTestCase(unittest.TestCase):
+ def setUp(self):
+ self.widget = Widget('The widget')
+
+ def tearDown(self):
+ self.widget.dispose()
+ self.widget = None
+
+If :meth:`setUp` succeeded, the :meth:`tearDown` method will be run whether
+:meth:`runTest` succeeded or not.
+
+Such a working environment for the testing code is called a :dfn:`fixture`.
+
+Often, many small test cases will use the same fixture. In this case, we would
+end up subclassing :class:`SimpleWidgetTestCase` into many small one-method
+classes such as :class:`DefaultWidgetSizeTestCase`. This is time-consuming and
+
+discouraging, so in the same vein as JUnit, :mod:`unittest` provides a simpler
+mechanism::
+
+ import unittest
+
+ class WidgetTestCase(unittest.TestCase):
+ def setUp(self):
+ self.widget = Widget('The widget')
+
+ def tearDown(self):
+ self.widget.dispose()
+ self.widget = None
+
+ def testDefaultSize(self):
+ self.failUnless(self.widget.size() == (50,50),
+ 'incorrect default size')
+
+ def testResize(self):
+ self.widget.resize(100,150)
+ self.failUnless(self.widget.size() == (100,150),
+ 'wrong size after resize')
+
+Here we have not provided a :meth:`runTest` method, but have instead provided
+two different test methods. Class instances will now each run one of the
+:meth:`test\*` methods, with ``self.widget`` created and destroyed separately
+for each instance. When creating an instance we must specify the test method it
+is to run. We do this by passing the method name in the constructor::
+
+ defaultSizeTestCase = WidgetTestCase('testDefaultSize')
+ resizeTestCase = WidgetTestCase('testResize')
+
+Test case instances are grouped together according to the features they test.
+:mod:`unittest` provides a mechanism for this: the :dfn:`test suite`,
+represented by :mod:`unittest`'s :class:`TestSuite` class::
+
+ widgetTestSuite = unittest.TestSuite()
+ widgetTestSuite.addTest(WidgetTestCase('testDefaultSize'))
+ widgetTestSuite.addTest(WidgetTestCase('testResize'))
+
+For the ease of running tests, as we will see later, it is a good idea to
+provide in each test module a callable object that returns a pre-built test
+suite::
+
+ def suite():
+ suite = unittest.TestSuite()
+ suite.addTest(WidgetTestCase('testDefaultSize'))
+ suite.addTest(WidgetTestCase('testResize'))
+ return suite
+
+or even::
+
+ def suite():
+ tests = ['testDefaultSize', 'testResize']
+
+ return unittest.TestSuite(map(WidgetTestCase, tests))
+
+Since it is a common pattern to create a :class:`TestCase` subclass with many
+similarly named test functions, :mod:`unittest` provides a :class:`TestLoader`
+class that can be used to automate the process of creating a test suite and
+populating it with individual tests. For example, ::
+
+ suite = unittest.TestLoader().loadTestsFromTestCase(WidgetTestCase)
+
+will create a test suite that will run ``WidgetTestCase.testDefaultSize()`` and
+``WidgetTestCase.testResize``. :class:`TestLoader` uses the ``'test'`` method
+name prefix to identify test methods automatically.
+
+Note that the order in which the various test cases will be run is determined by
+sorting the test function names with the built-in :func:`cmp` function.
+
+Often it is desirable to group suites of test cases together, so as to run tests
+for the whole system at once. This is easy, since :class:`TestSuite` instances
+can be added to a :class:`TestSuite` just as :class:`TestCase` instances can be
+added to a :class:`TestSuite`::
+
+ suite1 = module1.TheTestSuite()
+ suite2 = module2.TheTestSuite()
+ alltests = unittest.TestSuite([suite1, suite2])
+
+You can place the definitions of test cases and test suites in the same modules
+as the code they are to test (such as :file:`widget.py`), but there are several
+advantages to placing the test code in a separate module, such as
+:file:`test_widget.py`:
+
+* The test module can be run standalone from the command line.
+
+* The test code can more easily be separated from shipped code.
+
+* There is less temptation to change test code to fit the code it tests without
+ a good reason.
+
+* Test code should be modified much less frequently than the code it tests.
+
+* Tested code can be refactored more easily.
+
+* Tests for modules written in C must be in separate modules anyway, so why not
+ be consistent?
+
+* If the testing strategy changes, there is no need to change the source code.
+
+
+.. _legacy-unit-tests:
+
+Re-using old test code
+----------------------
+
+Some users will find that they have existing test code that they would like to
+run from :mod:`unittest`, without converting every old test function to a
+:class:`TestCase` subclass.
+
+For this reason, :mod:`unittest` provides a :class:`FunctionTestCase` class.
+This subclass of :class:`TestCase` can be used to wrap an existing test
+function. Set-up and tear-down functions can also be provided.
+
+Given the following test function::
+
+ def testSomething():
+ something = makeSomething()
+ assert something.name is not None
+ # ...
+
+one can create an equivalent test case instance as follows::
+
+ testcase = unittest.FunctionTestCase(testSomething)
+
+If there are additional set-up and tear-down methods that should be called as
+part of the test case's operation, they can also be provided like so::
+
+ testcase = unittest.FunctionTestCase(testSomething,
+ setUp=makeSomethingDB,
+ tearDown=deleteSomethingDB)
+
+To make migrating existing test suites easier, :mod:`unittest` supports tests
+raising :exc:`AssertionError` to indicate test failure. However, it is
+recommended that you use the explicit :meth:`TestCase.fail\*` and
+:meth:`TestCase.assert\*` methods instead, as future versions of :mod:`unittest`
+may treat :exc:`AssertionError` differently.
+
+.. note::
+
+ Even though :class:`FunctionTestCase` can be used to quickly convert an existing
+ test base over to a :mod:`unittest`\ -based system, this approach is not
+ recommended. Taking the time to set up proper :class:`TestCase` subclasses will
+ make future test refactorings infinitely easier.
+
+
+.. _unittest-contents:
+
+Classes and functions
+---------------------
+
+
+.. class:: TestCase([methodName])
+
+ Instances of the :class:`TestCase` class represent the smallest testable units
+ in the :mod:`unittest` universe. This class is intended to be used as a base
+ class, with specific tests being implemented by concrete subclasses. This class
+ implements the interface needed by the test runner to allow it to drive the
+ test, and methods that the test code can use to check for and report various
+ kinds of failure.
+
+ Each instance of :class:`TestCase` will run a single test method: the method
+ named *methodName*. If you remember, we had an earlier example that went
+ something like this::
+
+ def suite():
+ suite = unittest.TestSuite()
+ suite.addTest(WidgetTestCase('testDefaultSize'))
+ suite.addTest(WidgetTestCase('testResize'))
+ return suite
+
+ Here, we create two instances of :class:`WidgetTestCase`, each of which runs a
+ single test.
+
+ *methodName* defaults to ``'runTest'``.
+
+
+.. class:: FunctionTestCase(testFunc[, setUp[, tearDown[, description]]])
+
+ This class implements the portion of the :class:`TestCase` interface which
+ allows the test runner to drive the test, but does not provide the methods which
+ test code can use to check and report errors. This is used to create test cases
+ using legacy test code, allowing it to be integrated into a :mod:`unittest`\
+ -based test framework.
+
+
+.. class:: TestSuite([tests])
+
+ This class represents an aggregation of individual tests cases and test suites.
+ The class presents the interface needed by the test runner to allow it to be run
+ as any other test case. Running a :class:`TestSuite` instance is the same as
+ iterating over the suite, running each test individually.
+
+ If *tests* is given, it must be an iterable of individual test cases or other
+ test suites that will be used to build the suite initially. Additional methods
+ are provided to add test cases and suites to the collection later on.
+
+
+.. class:: TestLoader()
+
+ This class is responsible for loading tests according to various criteria and
+ returning them wrapped in a :class:`TestSuite`. It can load all tests within a
+ given module or :class:`TestCase` subclass.
+
+
+.. class:: TestResult()
+
+ This class is used to compile information about which tests have succeeded and
+ which have failed.
+
+
+.. data:: defaultTestLoader
+
+ Instance of the :class:`TestLoader` class intended to be shared. If no
+ customization of the :class:`TestLoader` is needed, this instance can be used
+ instead of repeatedly creating new instances.
+
+
+.. class:: TextTestRunner([stream[, descriptions[, verbosity]]])
+
+ A basic test runner implementation which prints results on standard error. It
+ has a few configurable parameters, but is essentially very simple. Graphical
+ applications which run test suites should provide alternate implementations.
+
+
+.. function:: main([module[, defaultTest[, argv[, testRunner[, testLoader]]]]])
+
+ A command-line program that runs a set of tests; this is primarily for making
+ test modules conveniently executable. The simplest use for this function is to
+ include the following line at the end of a test script::
+
+ if __name__ == '__main__':
+ unittest.main()
+
+ The *testRunner* argument can either be a test runner class or an already
+ created instance of it.
+
+In some cases, the existing tests may have been written using the :mod:`doctest`
+module. If so, that module provides a :class:`DocTestSuite` class that can
+automatically build :class:`unittest.TestSuite` instances from the existing
+:mod:`doctest`\ -based tests.
+
+.. versionadded:: 2.3
+
+
+.. _testcase-objects:
+
+TestCase Objects
+----------------
+
+Each :class:`TestCase` instance represents a single test, but each concrete
+subclass may be used to define multiple tests --- the concrete class represents
+a single test fixture. The fixture is created and cleaned up for each test
+case.
+
+:class:`TestCase` instances provide three groups of methods: one group used to
+run the test, another used by the test implementation to check conditions and
+report failures, and some inquiry methods allowing information about the test
+itself to be gathered.
+
+Methods in the first group (running the test) are:
+
+
+.. method:: TestCase.setUp()
+
+ Method called to prepare the test fixture. This is called immediately before
+ calling the test method; any exception raised by this method will be considered
+ an error rather than a test failure. The default implementation does nothing.
+
+
+.. method:: TestCase.tearDown()
+
+ Method called immediately after the test method has been called and the result
+ recorded. This is called even if the test method raised an exception, so the
+ implementation in subclasses may need to be particularly careful about checking
+ internal state. Any exception raised by this method will be considered an error
+ rather than a test failure. This method will only be called if the
+ :meth:`setUp` succeeds, regardless of the outcome of the test method. The
+ default implementation does nothing.
+
+
+.. method:: TestCase.run([result])
+
+ Run the test, collecting the result into the test result object passed as
+ *result*. If *result* is omitted or :const:`None`, a temporary result object is
+ created (by calling the :meth:`defaultTestCase` method) and used; this result
+ object is not returned to :meth:`run`'s caller.
+
+ The same effect may be had by simply calling the :class:`TestCase` instance.
+
+
+.. method:: TestCase.debug()
+
+ Run the test without collecting the result. This allows exceptions raised by
+ the test to be propagated to the caller, and can be used to support running
+ tests under a debugger.
+
+The test code can use any of the following methods to check for and report
+failures.
+
+
+.. method:: TestCase.assert_(expr[, msg])
+ TestCase.failUnless(expr[, msg])
+
+ Signal a test failure if *expr* is false; the explanation for the error will be
+ *msg* if given, otherwise it will be :const:`None`.
+
+
+.. method:: TestCase.assertEqual(first, second[, msg])
+ TestCase.failUnlessEqual(first, second[, msg])
+
+ Test that *first* and *second* are equal. If the values do not compare equal,
+ the test will fail with the explanation given by *msg*, or :const:`None`. Note
+ that using :meth:`failUnlessEqual` improves upon doing the comparison as the
+ first parameter to :meth:`failUnless`: the default value for *msg* can be
+ computed to include representations of both *first* and *second*.
+
+
+.. method:: TestCase.assertNotEqual(first, second[, msg])
+ TestCase.failIfEqual(first, second[, msg])
+
+ Test that *first* and *second* are not equal. If the values do compare equal,
+ the test will fail with the explanation given by *msg*, or :const:`None`. Note
+ that using :meth:`failIfEqual` improves upon doing the comparison as the first
+ parameter to :meth:`failUnless` is that the default value for *msg* can be
+ computed to include representations of both *first* and *second*.
+
+
+.. method:: TestCase.assertAlmostEqual(first, second[, places[, msg]])
+ TestCase.failUnlessAlmostEqual(first, second[, places[, msg]])
+
+ Test that *first* and *second* are approximately equal by computing the
+ difference, rounding to the given number of *places*, and comparing to zero.
+ Note that comparing a given number of decimal places is not the same as
+ comparing a given number of significant digits. If the values do not compare
+ equal, the test will fail with the explanation given by *msg*, or :const:`None`.
+
+
+.. method:: TestCase.assertNotAlmostEqual(first, second[, places[, msg]])
+ TestCase.failIfAlmostEqual(first, second[, places[, msg]])
+
+ Test that *first* and *second* are not approximately equal by computing the
+ difference, rounding to the given number of *places*, and comparing to zero.
+ Note that comparing a given number of decimal places is not the same as
+ comparing a given number of significant digits. If the values do not compare
+ equal, the test will fail with the explanation given by *msg*, or :const:`None`.
+
+
+.. method:: TestCase.assertRaises(exception, callable, ...)
+ TestCase.failUnlessRaises(exception, callable, ...)
+
+ Test that an exception is raised when *callable* is called with any positional
+ or keyword arguments that are also passed to :meth:`assertRaises`. The test
+ passes if *exception* is raised, is an error if another exception is raised, or
+ fails if no exception is raised. To catch any of a group of exceptions, a tuple
+ containing the exception classes may be passed as *exception*.
+
+
+.. method:: TestCase.failIf(expr[, msg])
+
+ The inverse of the :meth:`failUnless` method is the :meth:`failIf` method. This
+ signals a test failure if *expr* is true, with *msg* or :const:`None` for the
+ error message.
+
+
+.. method:: TestCase.fail([msg])
+
+ Signals a test failure unconditionally, with *msg* or :const:`None` for the
+ error message.
+
+
+.. attribute:: TestCase.failureException
+
+ This class attribute gives the exception raised by the :meth:`test` method. If
+ a test framework needs to use a specialized exception, possibly to carry
+ additional information, it must subclass this exception in order to "play fair"
+ with the framework. The initial value of this attribute is
+ :exc:`AssertionError`.
+
+Testing frameworks can use the following methods to collect information on the
+test:
+
+
+.. method:: TestCase.countTestCases()
+
+ Return the number of tests represented by this test object. For
+ :class:`TestCase` instances, this will always be ``1``.
+
+
+.. method:: TestCase.defaultTestResult()
+
+ Return an instance of the test result class that should be used for this test
+ case class (if no other result instance is provided to the :meth:`run` method).
+
+ For :class:`TestCase` instances, this will always be an instance of
+ :class:`TestResult`; subclasses of :class:`TestCase` should override this as
+ necessary.
+
+
+.. method:: TestCase.id()
+
+ Return a string identifying the specific test case. This is usually the full
+ name of the test method, including the module and class name.
+
+
+.. method:: TestCase.shortDescription()
+
+ Returns a one-line description of the test, or :const:`None` if no description
+ has been provided. The default implementation of this method returns the first
+ line of the test method's docstring, if available, or :const:`None`.
+
+
+.. _testsuite-objects:
+
+TestSuite Objects
+-----------------
+
+:class:`TestSuite` objects behave much like :class:`TestCase` objects, except
+they do not actually implement a test. Instead, they are used to aggregate
+tests into groups of tests that should be run together. Some additional methods
+are available to add tests to :class:`TestSuite` instances:
+
+
+.. method:: TestSuite.addTest(test)
+
+ Add a :class:`TestCase` or :class:`TestSuite` to the suite.
+
+
+.. method:: TestSuite.addTests(tests)
+
+ Add all the tests from an iterable of :class:`TestCase` and :class:`TestSuite`
+ instances to this test suite.
+
+ This is equivalent to iterating over *tests*, calling :meth:`addTest` for each
+ element.
+
+:class:`TestSuite` shares the following methods with :class:`TestCase`:
+
+
+.. method:: TestSuite.run(result)
+
+ Run the tests associated with this suite, collecting the result into the test
+ result object passed as *result*. Note that unlike :meth:`TestCase.run`,
+ :meth:`TestSuite.run` requires the result object to be passed in.
+
+
+.. method:: TestSuite.debug()
+
+ Run the tests associated with this suite without collecting the result. This
+ allows exceptions raised by the test to be propagated to the caller and can be
+ used to support running tests under a debugger.
+
+
+.. method:: TestSuite.countTestCases()
+
+ Return the number of tests represented by this test object, including all
+ individual tests and sub-suites.
+
+In the typical usage of a :class:`TestSuite` object, the :meth:`run` method is
+invoked by a :class:`TestRunner` rather than by the end-user test harness.
+
+
+.. _testresult-objects:
+
+TestResult Objects
+------------------
+
+A :class:`TestResult` object stores the results of a set of tests. The
+:class:`TestCase` and :class:`TestSuite` classes ensure that results are
+properly recorded; test authors do not need to worry about recording the outcome
+of tests.
+
+Testing frameworks built on top of :mod:`unittest` may want access to the
+:class:`TestResult` object generated by running a set of tests for reporting
+purposes; a :class:`TestResult` instance is returned by the
+:meth:`TestRunner.run` method for this purpose.
+
+:class:`TestResult` instances have the following attributes that will be of
+interest when inspecting the results of running a set of tests:
+
+
+.. attribute:: TestResult.errors
+
+ A list containing 2-tuples of :class:`TestCase` instances and strings holding
+ formatted tracebacks. Each tuple represents a test which raised an unexpected
+ exception.
+
+ .. versionchanged:: 2.2
+ Contains formatted tracebacks instead of :func:`sys.exc_info` results.
+
+
+.. attribute:: TestResult.failures
+
+ A list containing 2-tuples of :class:`TestCase` instances and strings holding
+ formatted tracebacks. Each tuple represents a test where a failure was
+ explicitly signalled using the :meth:`TestCase.fail\*` or
+ :meth:`TestCase.assert\*` methods.
+
+ .. versionchanged:: 2.2
+ Contains formatted tracebacks instead of :func:`sys.exc_info` results.
+
+
+.. attribute:: TestResult.testsRun
+
+ The total number of tests run so far.
+
+
+.. method:: TestResult.wasSuccessful()
+
+ Returns :const:`True` if all tests run so far have passed, otherwise returns
+ :const:`False`.
+
+
+.. method:: TestResult.stop()
+
+ This method can be called to signal that the set of tests being run should be
+ aborted by setting the :class:`TestResult`'s ``shouldStop`` attribute to
+ :const:`True`. :class:`TestRunner` objects should respect this flag and return
+ without running any additional tests.
+
+ For example, this feature is used by the :class:`TextTestRunner` class to stop
+ the test framework when the user signals an interrupt from the keyboard.
+ Interactive tools which provide :class:`TestRunner` implementations can use this
+ in a similar manner.
+
+The following methods of the :class:`TestResult` class are used to maintain the
+internal data structures, and may be extended in subclasses to support
+additional reporting requirements. This is particularly useful in building
+tools which support interactive reporting while tests are being run.
+
+
+.. method:: TestResult.startTest(test)
+
+ Called when the test case *test* is about to be run.
+
+ The default implementation simply increments the instance's ``testsRun``
+ counter.
+
+
+.. method:: TestResult.stopTest(test)
+
+ Called after the test case *test* has been executed, regardless of the outcome.
+
+ The default implementation does nothing.
+
+
+.. method:: TestResult.addError(test, err)
+
+ Called when the test case *test* raises an unexpected exception *err* is a tuple
+ of the form returned by :func:`sys.exc_info`: ``(type, value, traceback)``.
+
+ The default implementation appends ``(test, err)`` to the instance's ``errors``
+ attribute.
+
+
+.. method:: TestResult.addFailure(test, err)
+
+ Called when the test case *test* signals a failure. *err* is a tuple of the form
+ returned by :func:`sys.exc_info`: ``(type, value, traceback)``.
+
+ The default implementation appends ``(test, err)`` to the instance's
+ ``failures`` attribute.
+
+
+.. method:: TestResult.addSuccess(test)
+
+ Called when the test case *test* succeeds.
+
+ The default implementation does nothing.
+
+
+.. _testloader-objects:
+
+TestLoader Objects
+------------------
+
+The :class:`TestLoader` class is used to create test suites from classes and
+modules. Normally, there is no need to create an instance of this class; the
+:mod:`unittest` module provides an instance that can be shared as
+``unittest.defaultTestLoader``. Using a subclass or instance, however, allows
+customization of some configurable properties.
+
+:class:`TestLoader` objects have the following methods:
+
+
+.. method:: TestLoader.loadTestsFromTestCase(testCaseClass)
+
+ Return a suite of all tests cases contained in the :class:`TestCase`\ -derived
+ :class:`testCaseClass`.
+
+
+.. method:: TestLoader.loadTestsFromModule(module)
+
+ Return a suite of all tests cases contained in the given module. This method
+ searches *module* for classes derived from :class:`TestCase` and creates an
+ instance of the class for each test method defined for the class.
+
+ .. warning::
+
+ While using a hierarchy of :class:`TestCase`\ -derived classes can be convenient
+ in sharing fixtures and helper functions, defining test methods on base classes
+ that are not intended to be instantiated directly does not play well with this
+ method. Doing so, however, can be useful when the fixtures are different and
+ defined in subclasses.
+
+
+.. method:: TestLoader.loadTestsFromName(name[, module])
+
+ Return a suite of all tests cases given a string specifier.
+
+ The specifier *name* is a "dotted name" that may resolve either to a module, a
+ test case class, a test method within a test case class, a :class:`TestSuite`
+ instance, or a callable object which returns a :class:`TestCase` or
+ :class:`TestSuite` instance. These checks are applied in the order listed here;
+ that is, a method on a possible test case class will be picked up as "a test
+ method within a test case class", rather than "a callable object".
+
+ For example, if you have a module :mod:`SampleTests` containing a
+ :class:`TestCase`\ -derived class :class:`SampleTestCase` with three test
+ methods (:meth:`test_one`, :meth:`test_two`, and :meth:`test_three`), the
+ specifier ``'SampleTests.SampleTestCase'`` would cause this method to return a
+ suite which will run all three test methods. Using the specifier
+ ``'SampleTests.SampleTestCase.test_two'`` would cause it to return a test suite
+ which will run only the :meth:`test_two` test method. The specifier can refer
+ to modules and packages which have not been imported; they will be imported as a
+ side-effect.
+
+ The method optionally resolves *name* relative to the given *module*.
+
+
+.. method:: TestLoader.loadTestsFromNames(names[, module])
+
+ Similar to :meth:`loadTestsFromName`, but takes a sequence of names rather than
+ a single name. The return value is a test suite which supports all the tests
+ defined for each name.
+
+
+.. method:: TestLoader.getTestCaseNames(testCaseClass)
+
+ Return a sorted sequence of method names found within *testCaseClass*; this
+ should be a subclass of :class:`TestCase`.
+
+The following attributes of a :class:`TestLoader` can be configured either by
+subclassing or assignment on an instance:
+
+
+.. attribute:: TestLoader.testMethodPrefix
+
+ String giving the prefix of method names which will be interpreted as test
+ methods. The default value is ``'test'``.
+
+ This affects :meth:`getTestCaseNames` and all the :meth:`loadTestsFrom\*`
+ methods.
+
+
+.. attribute:: TestLoader.sortTestMethodsUsing
+
+ Function to be used to compare method names when sorting them in
+ :meth:`getTestCaseNames` and all the :meth:`loadTestsFrom\*` methods. The
+ default value is the built-in :func:`cmp` function; the attribute can also be
+ set to :const:`None` to disable the sort.
+
+
+.. attribute:: TestLoader.suiteClass
+
+ Callable object that constructs a test suite from a list of tests. No methods on
+ the resulting object are needed. The default value is the :class:`TestSuite`
+ class.
+
+ This affects all the :meth:`loadTestsFrom\*` methods.
+
diff --git a/Doc/library/unix.rst b/Doc/library/unix.rst
new file mode 100644
index 0000000000..b60af0fe1c
--- /dev/null
+++ b/Doc/library/unix.rst
@@ -0,0 +1,29 @@
+
+.. _unix:
+
+**********************
+Unix Specific Services
+**********************
+
+The modules described in this chapter provide interfaces to features that are
+unique to the Unix operating system, or in some cases to some or many variants
+of it. Here's an overview:
+
+
+.. toctree::
+
+ posix.rst
+ pwd.rst
+ spwd.rst
+ grp.rst
+ crypt.rst
+ dl.rst
+ termios.rst
+ tty.rst
+ pty.rst
+ fcntl.rst
+ pipes.rst
+ resource.rst
+ nis.rst
+ syslog.rst
+ commands.rst
diff --git a/Doc/library/urllib.rst b/Doc/library/urllib.rst
new file mode 100644
index 0000000000..ef8264f9e7
--- /dev/null
+++ b/Doc/library/urllib.rst
@@ -0,0 +1,471 @@
+
+:mod:`urllib` --- Open arbitrary resources by URL
+=================================================
+
+.. module:: urllib
+ :synopsis: Open an arbitrary network resource by URL (requires sockets).
+
+
+.. index::
+ single: WWW
+ single: World Wide Web
+ single: URL
+
+This module provides a high-level interface for fetching data across the World
+Wide Web. In particular, the :func:`urlopen` function is similar to the
+built-in function :func:`open`, but accepts Universal Resource Locators (URLs)
+instead of filenames. Some restrictions apply --- it can only open URLs for
+reading, and no seek operations are available.
+
+It defines the following public functions:
+
+
+.. function:: urlopen(url[, data[, proxies]])
+
+ Open a network object denoted by a URL for reading. If the URL does not have a
+ scheme identifier, or if it has :file:`file:` as its scheme identifier, this
+ opens a local file (without universal newlines); otherwise it opens a socket to
+ a server somewhere on the network. If the connection cannot be made the
+ :exc:`IOError` exception is raised. If all went well, a file-like object is
+ returned. This supports the following methods: :meth:`read`, :meth:`readline`,
+ :meth:`readlines`, :meth:`fileno`, :meth:`close`, :meth:`info` and
+ :meth:`geturl`. It also has proper support for the iterator protocol. One
+ caveat: the :meth:`read` method, if the size argument is omitted or negative,
+ may not read until the end of the data stream; there is no good way to determine
+ that the entire stream from a socket has been read in the general case.
+
+ Except for the :meth:`info` and :meth:`geturl` methods, these methods have the
+ same interface as for file objects --- see section :ref:`bltin-file-objects` in
+ this manual. (It is not a built-in file object, however, so it can't be used at
+ those few places where a true built-in file object is required.)
+
+ .. index:: module: mimetools
+
+ The :meth:`info` method returns an instance of the class
+ :class:`mimetools.Message` containing meta-information associated with the
+ URL. When the method is HTTP, these headers are those returned by the server
+ at the head of the retrieved HTML page (including Content-Length and
+ Content-Type). When the method is FTP, a Content-Length header will be
+ present if (as is now usual) the server passed back a file length in response
+ to the FTP retrieval request. A Content-Type header will be present if the
+ MIME type can be guessed. When the method is local-file, returned headers
+ will include a Date representing the file's last-modified time, a
+ Content-Length giving file size, and a Content-Type containing a guess at the
+ file's type. See also the description of the :mod:`mimetools` module.
+
+ The :meth:`geturl` method returns the real URL of the page. In some cases, the
+ HTTP server redirects a client to another URL. The :func:`urlopen` function
+ handles this transparently, but in some cases the caller needs to know which URL
+ the client was redirected to. The :meth:`geturl` method can be used to get at
+ this redirected URL.
+
+ If the *url* uses the :file:`http:` scheme identifier, the optional *data*
+ argument may be given to specify a ``POST`` request (normally the request type
+ is ``GET``). The *data* argument must be in standard
+ :mimetype:`application/x-www-form-urlencoded` format; see the :func:`urlencode`
+ function below.
+
+ The :func:`urlopen` function works transparently with proxies which do not
+ require authentication. In a Unix or Windows environment, set the
+ :envvar:`http_proxy`, or :envvar:`ftp_proxy` environment variables to a URL that
+ identifies the proxy server before starting the Python interpreter. For example
+ (the ``'%'`` is the command prompt)::
+
+ % http_proxy="http://www.someproxy.com:3128"
+ % export http_proxy
+ % python
+ ...
+
+ In a Windows environment, if no proxy environment variables are set, proxy
+ settings are obtained from the registry's Internet Settings section.
+
+ .. index:: single: Internet Config
+
+ In a Macintosh environment, :func:`urlopen` will retrieve proxy information from
+ Internet Config.
+
+ Alternatively, the optional *proxies* argument may be used to explicitly specify
+ proxies. It must be a dictionary mapping scheme names to proxy URLs, where an
+ empty dictionary causes no proxies to be used, and ``None`` (the default value)
+ causes environmental proxy settings to be used as discussed above. For
+ example::
+
+ # Use http://www.someproxy.com:3128 for http proxying
+ proxies = {'http': 'http://www.someproxy.com:3128'}
+ filehandle = urllib.urlopen(some_url, proxies=proxies)
+ # Don't use any proxies
+ filehandle = urllib.urlopen(some_url, proxies={})
+ # Use proxies from environment - both versions are equivalent
+ filehandle = urllib.urlopen(some_url, proxies=None)
+ filehandle = urllib.urlopen(some_url)
+
+ The :func:`urlopen` function does not support explicit proxy specification. If
+ you need to override environmental proxy settings, use :class:`URLopener`, or a
+ subclass such as :class:`FancyURLopener`.
+
+ Proxies which require authentication for use are not currently supported; this
+ is considered an implementation limitation.
+
+ .. versionchanged:: 2.3
+ Added the *proxies* support.
+
+
+.. function:: urlretrieve(url[, filename[, reporthook[, data]]])
+
+ Copy a network object denoted by a URL to a local file, if necessary. If the URL
+ points to a local file, or a valid cached copy of the object exists, the object
+ is not copied. Return a tuple ``(filename, headers)`` where *filename* is the
+ local file name under which the object can be found, and *headers* is whatever
+ the :meth:`info` method of the object returned by :func:`urlopen` returned (for
+ a remote object, possibly cached). Exceptions are the same as for
+ :func:`urlopen`.
+
+ The second argument, if present, specifies the file location to copy to (if
+ absent, the location will be a tempfile with a generated name). The third
+ argument, if present, is a hook function that will be called once on
+ establishment of the network connection and once after each block read
+ thereafter. The hook will be passed three arguments; a count of blocks
+ transferred so far, a block size in bytes, and the total size of the file. The
+ third argument may be ``-1`` on older FTP servers which do not return a file
+ size in response to a retrieval request.
+
+ If the *url* uses the :file:`http:` scheme identifier, the optional *data*
+ argument may be given to specify a ``POST`` request (normally the request type
+ is ``GET``). The *data* argument must in standard
+ :mimetype:`application/x-www-form-urlencoded` format; see the :func:`urlencode`
+ function below.
+
+ .. versionchanged:: 2.5
+ :func:`urlretrieve` will raise :exc:`ContentTooShortError` when it detects that
+ the amount of data available was less than the expected amount (which is the
+ size reported by a *Content-Length* header). This can occur, for example, when
+ the download is interrupted.
+
+ The *Content-Length* is treated as a lower bound: if there's more data to read,
+ urlretrieve reads more data, but if less data is available, it raises the
+ exception.
+
+ You can still retrieve the downloaded data in this case, it is stored in the
+ :attr:`content` attribute of the exception instance.
+
+ If no *Content-Length* header was supplied, urlretrieve can not check the size
+ of the data it has downloaded, and just returns it. In this case you just have
+ to assume that the download was successful.
+
+
+.. data:: _urlopener
+
+ The public functions :func:`urlopen` and :func:`urlretrieve` create an instance
+ of the :class:`FancyURLopener` class and use it to perform their requested
+ actions. To override this functionality, programmers can create a subclass of
+ :class:`URLopener` or :class:`FancyURLopener`, then assign an instance of that
+ class to the ``urllib._urlopener`` variable before calling the desired function.
+ For example, applications may want to specify a different
+ :mailheader:`User-Agent` header than :class:`URLopener` defines. This can be
+ accomplished with the following code::
+
+ import urllib
+
+ class AppURLopener(urllib.FancyURLopener):
+ version = "App/1.7"
+
+ urllib._urlopener = AppURLopener()
+
+
+.. function:: urlcleanup()
+
+ Clear the cache that may have been built up by previous calls to
+ :func:`urlretrieve`.
+
+
+.. function:: quote(string[, safe])
+
+ Replace special characters in *string* using the ``%xx`` escape. Letters,
+ digits, and the characters ``'_.-'`` are never quoted. The optional *safe*
+ parameter specifies additional characters that should not be quoted --- its
+ default value is ``'/'``.
+
+ Example: ``quote('/~connolly/')`` yields ``'/%7econnolly/'``.
+
+
+.. function:: quote_plus(string[, safe])
+
+ Like :func:`quote`, but also replaces spaces by plus signs, as required for
+ quoting HTML form values. Plus signs in the original string are escaped unless
+ they are included in *safe*. It also does not have *safe* default to ``'/'``.
+
+
+.. function:: unquote(string)
+
+ Replace ``%xx`` escapes by their single-character equivalent.
+
+ Example: ``unquote('/%7Econnolly/')`` yields ``'/~connolly/'``.
+
+
+.. function:: unquote_plus(string)
+
+ Like :func:`unquote`, but also replaces plus signs by spaces, as required for
+ unquoting HTML form values.
+
+
+.. function:: urlencode(query[, doseq])
+
+ Convert a mapping object or a sequence of two-element tuples to a "url-encoded"
+ string, suitable to pass to :func:`urlopen` above as the optional *data*
+ argument. This is useful to pass a dictionary of form fields to a ``POST``
+ request. The resulting string is a series of ``key=value`` pairs separated by
+ ``'&'`` characters, where both *key* and *value* are quoted using
+ :func:`quote_plus` above. If the optional parameter *doseq* is present and
+ evaluates to true, individual ``key=value`` pairs are generated for each element
+ of the sequence. When a sequence of two-element tuples is used as the *query*
+ argument, the first element of each tuple is a key and the second is a value.
+ The order of parameters in the encoded string will match the order of parameter
+ tuples in the sequence. The :mod:`cgi` module provides the functions
+ :func:`parse_qs` and :func:`parse_qsl` which are used to parse query strings
+ into Python data structures.
+
+
+.. function:: pathname2url(path)
+
+ Convert the pathname *path* from the local syntax for a path to the form used in
+ the path component of a URL. This does not produce a complete URL. The return
+ value will already be quoted using the :func:`quote` function.
+
+
+.. function:: url2pathname(path)
+
+ Convert the path component *path* from an encoded URL to the local syntax for a
+ path. This does not accept a complete URL. This function uses :func:`unquote`
+ to decode *path*.
+
+
+.. class:: URLopener([proxies[, **x509]])
+
+ Base class for opening and reading URLs. Unless you need to support opening
+ objects using schemes other than :file:`http:`, :file:`ftp:`, or :file:`file:`,
+ you probably want to use :class:`FancyURLopener`.
+
+ By default, the :class:`URLopener` class sends a :mailheader:`User-Agent` header
+ of ``urllib/VVV``, where *VVV* is the :mod:`urllib` version number.
+ Applications can define their own :mailheader:`User-Agent` header by subclassing
+ :class:`URLopener` or :class:`FancyURLopener` and setting the class attribute
+ :attr:`version` to an appropriate string value in the subclass definition.
+
+ The optional *proxies* parameter should be a dictionary mapping scheme names to
+ proxy URLs, where an empty dictionary turns proxies off completely. Its default
+ value is ``None``, in which case environmental proxy settings will be used if
+ present, as discussed in the definition of :func:`urlopen`, above.
+
+ Additional keyword parameters, collected in *x509*, may be used for
+ authentication of the client when using the :file:`https:` scheme. The keywords
+ *key_file* and *cert_file* are supported to provide an SSL key and certificate;
+ both are needed to support client authentication.
+
+ :class:`URLopener` objects will raise an :exc:`IOError` exception if the server
+ returns an error code.
+
+
+.. class:: FancyURLopener(...)
+
+ :class:`FancyURLopener` subclasses :class:`URLopener` providing default handling
+ for the following HTTP response codes: 301, 302, 303, 307 and 401. For the 30x
+ response codes listed above, the :mailheader:`Location` header is used to fetch
+ the actual URL. For 401 response codes (authentication required), basic HTTP
+ authentication is performed. For the 30x response codes, recursion is bounded
+ by the value of the *maxtries* attribute, which defaults to 10.
+
+ For all other response codes, the method :meth:`http_error_default` is called
+ which you can override in subclasses to handle the error appropriately.
+
+ .. note::
+
+ According to the letter of :rfc:`2616`, 301 and 302 responses to POST requests
+ must not be automatically redirected without confirmation by the user. In
+ reality, browsers do allow automatic redirection of these responses, changing
+ the POST to a GET, and :mod:`urllib` reproduces this behaviour.
+
+ The parameters to the constructor are the same as those for :class:`URLopener`.
+
+ .. note::
+
+ When performing basic authentication, a :class:`FancyURLopener` instance calls
+ its :meth:`prompt_user_passwd` method. The default implementation asks the
+ users for the required information on the controlling terminal. A subclass may
+ override this method to support more appropriate behavior if needed.
+
+
+.. exception:: ContentTooShortError(msg[, content])
+
+ This exception is raised when the :func:`urlretrieve` function detects that the
+ amount of the downloaded data is less than the expected amount (given by the
+ *Content-Length* header). The :attr:`content` attribute stores the downloaded
+ (and supposedly truncated) data.
+
+ .. versionadded:: 2.5
+
+Restrictions:
+
+ .. index::
+ pair: HTTP; protocol
+ pair: FTP; protocol
+
+* Currently, only the following protocols are supported: HTTP, (versions 0.9 and
+ 1.0), FTP, and local files.
+
+* The caching feature of :func:`urlretrieve` has been disabled until I find the
+ time to hack proper processing of Expiration time headers.
+
+* There should be a function to query whether a particular URL is in the cache.
+
+* For backward compatibility, if a URL appears to point to a local file but the
+ file can't be opened, the URL is re-interpreted using the FTP protocol. This
+ can sometimes cause confusing error messages.
+
+* The :func:`urlopen` and :func:`urlretrieve` functions can cause arbitrarily
+ long delays while waiting for a network connection to be set up. This means
+ that it is difficult to build an interactive Web client using these functions
+ without using threads.
+
+ .. index::
+ single: HTML
+ pair: HTTP; protocol
+ module: htmllib
+
+* The data returned by :func:`urlopen` or :func:`urlretrieve` is the raw data
+ returned by the server. This may be binary data (such as an image), plain text
+ or (for example) HTML. The HTTP protocol provides type information in the reply
+ header, which can be inspected by looking at the :mailheader:`Content-Type`
+ header. If the returned data is HTML, you can use the module :mod:`htmllib` to
+ parse it.
+
+ .. index:: single: FTP
+
+* The code handling the FTP protocol cannot differentiate between a file and a
+ directory. This can lead to unexpected behavior when attempting to read a URL
+ that points to a file that is not accessible. If the URL ends in a ``/``, it is
+ assumed to refer to a directory and will be handled accordingly. But if an
+ attempt to read a file leads to a 550 error (meaning the URL cannot be found or
+ is not accessible, often for permission reasons), then the path is treated as a
+ directory in order to handle the case when a directory is specified by a URL but
+ the trailing ``/`` has been left off. This can cause misleading results when
+ you try to fetch a file whose read permissions make it inaccessible; the FTP
+ code will try to read it, fail with a 550 error, and then perform a directory
+ listing for the unreadable file. If fine-grained control is needed, consider
+ using the :mod:`ftplib` module, subclassing :class:`FancyURLOpener`, or changing
+ *_urlopener* to meet your needs.
+
+* This module does not support the use of proxies which require authentication.
+ This may be implemented in the future.
+
+ .. index:: module: urlparse
+
+* Although the :mod:`urllib` module contains (undocumented) routines to parse
+ and unparse URL strings, the recommended interface for URL manipulation is in
+ module :mod:`urlparse`.
+
+
+.. _urlopener-objs:
+
+URLopener Objects
+-----------------
+
+.. sectionauthor:: Skip Montanaro <skip@mojam.com>
+
+
+:class:`URLopener` and :class:`FancyURLopener` objects have the following
+attributes.
+
+
+.. method:: URLopener.open(fullurl[, data])
+
+ Open *fullurl* using the appropriate protocol. This method sets up cache and
+ proxy information, then calls the appropriate open method with its input
+ arguments. If the scheme is not recognized, :meth:`open_unknown` is called.
+ The *data* argument has the same meaning as the *data* argument of
+ :func:`urlopen`.
+
+
+.. method:: URLopener.open_unknown(fullurl[, data])
+
+ Overridable interface to open unknown URL types.
+
+
+.. method:: URLopener.retrieve(url[, filename[, reporthook[, data]]])
+
+ Retrieves the contents of *url* and places it in *filename*. The return value
+ is a tuple consisting of a local filename and either a
+ :class:`mimetools.Message` object containing the response headers (for remote
+ URLs) or ``None`` (for local URLs). The caller must then open and read the
+ contents of *filename*. If *filename* is not given and the URL refers to a
+ local file, the input filename is returned. If the URL is non-local and
+ *filename* is not given, the filename is the output of :func:`tempfile.mktemp`
+ with a suffix that matches the suffix of the last path component of the input
+ URL. If *reporthook* is given, it must be a function accepting three numeric
+ parameters. It will be called after each chunk of data is read from the
+ network. *reporthook* is ignored for local URLs.
+
+ If the *url* uses the :file:`http:` scheme identifier, the optional *data*
+ argument may be given to specify a ``POST`` request (normally the request type
+ is ``GET``). The *data* argument must in standard
+ :mimetype:`application/x-www-form-urlencoded` format; see the :func:`urlencode`
+ function below.
+
+
+.. attribute:: URLopener.version
+
+ Variable that specifies the user agent of the opener object. To get
+ :mod:`urllib` to tell servers that it is a particular user agent, set this in a
+ subclass as a class variable or in the constructor before calling the base
+ constructor.
+
+The :class:`FancyURLopener` class offers one additional method that should be
+overloaded to provide the appropriate behavior:
+
+
+.. method:: FancyURLopener.prompt_user_passwd(host, realm)
+
+ Return information needed to authenticate the user at the given host in the
+ specified security realm. The return value should be a tuple, ``(user,
+ password)``, which can be used for basic authentication.
+
+ The implementation prompts for this information on the terminal; an application
+ should override this method to use an appropriate interaction model in the local
+ environment.
+
+
+.. _urllib-examples:
+
+Examples
+--------
+
+Here is an example session that uses the ``GET`` method to retrieve a URL
+containing parameters::
+
+ >>> import urllib
+ >>> params = urllib.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0})
+ >>> f = urllib.urlopen("http://www.musi-cal.com/cgi-bin/query?%s" % params)
+ >>> print f.read()
+
+The following example uses the ``POST`` method instead::
+
+ >>> import urllib
+ >>> params = urllib.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0})
+ >>> f = urllib.urlopen("http://www.musi-cal.com/cgi-bin/query", params)
+ >>> print f.read()
+
+The following example uses an explicitly specified HTTP proxy, overriding
+environment settings::
+
+ >>> import urllib
+ >>> proxies = {'http': 'http://proxy.example.com:8080/'}
+ >>> opener = urllib.FancyURLopener(proxies)
+ >>> f = opener.open("http://www.python.org")
+ >>> f.read()
+
+The following example uses no proxies at all, overriding environment settings::
+
+ >>> import urllib
+ >>> opener = urllib.FancyURLopener({})
+ >>> f = opener.open("http://www.python.org/")
+ >>> f.read()
+
diff --git a/Doc/library/urllib2.rst b/Doc/library/urllib2.rst
new file mode 100644
index 0000000000..41bb033e9a
--- /dev/null
+++ b/Doc/library/urllib2.rst
@@ -0,0 +1,927 @@
+:mod:`urllib2` --- extensible library for opening URLs
+======================================================
+
+.. module:: urllib2
+ :synopsis: Next generation URL opening library.
+.. moduleauthor:: Jeremy Hylton <jhylton@users.sourceforge.net>
+.. sectionauthor:: Moshe Zadka <moshez@users.sourceforge.net>
+
+
+The :mod:`urllib2` module defines functions and classes which help in opening
+URLs (mostly HTTP) in a complex world --- basic and digest authentication,
+redirections, cookies and more.
+
+The :mod:`urllib2` module defines the following functions:
+
+
+.. function:: urlopen(url[, data][, timeout])
+
+ Open the URL *url*, which can be either a string or a :class:`Request` object.
+
+ *data* may be a string specifying additional data to send to the server, or
+ ``None`` if no such data is needed. Currently HTTP requests are the only ones
+ that use *data*; the HTTP request will be a POST instead of a GET when the
+ *data* parameter is provided. *data* should be a buffer in the standard
+ :mimetype:`application/x-www-form-urlencoded` format. The
+ :func:`urllib.urlencode` function takes a mapping or sequence of 2-tuples and
+ returns a string in this format.
+
+ The optional *timeout* parameter specifies a timeout in seconds for the
+ connection attempt (if not specified, or passed as None, the global default
+ timeout setting will be used). This actually only work for HTTP, HTTPS, FTP and
+ FTPS connections.
+
+ This function returns a file-like object with two additional methods:
+
+ * :meth:`geturl` --- return the URL of the resource retrieved
+
+ * :meth:`info` --- return the meta-information of the page, as a dictionary-like
+ object
+
+ Raises :exc:`URLError` on errors.
+
+ Note that ``None`` may be returned if no handler handles the request (though the
+ default installed global :class:`OpenerDirector` uses :class:`UnknownHandler` to
+ ensure this never happens).
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. function:: install_opener(opener)
+
+ Install an :class:`OpenerDirector` instance as the default global opener.
+ Installing an opener is only necessary if you want urlopen to use that opener;
+ otherwise, simply call :meth:`OpenerDirector.open` instead of :func:`urlopen`.
+ The code does not check for a real :class:`OpenerDirector`, and any class with
+ the appropriate interface will work.
+
+
+.. function:: build_opener([handler, ...])
+
+ Return an :class:`OpenerDirector` instance, which chains the handlers in the
+ order given. *handler*\s can be either instances of :class:`BaseHandler`, or
+ subclasses of :class:`BaseHandler` (in which case it must be possible to call
+ the constructor without any parameters). Instances of the following classes
+ will be in front of the *handler*\s, unless the *handler*\s contain them,
+ instances of them or subclasses of them: :class:`ProxyHandler`,
+ :class:`UnknownHandler`, :class:`HTTPHandler`, :class:`HTTPDefaultErrorHandler`,
+ :class:`HTTPRedirectHandler`, :class:`FTPHandler`, :class:`FileHandler`,
+ :class:`HTTPErrorProcessor`.
+
+ If the Python installation has SSL support (:func:`socket.ssl` exists),
+ :class:`HTTPSHandler` will also be added.
+
+ Beginning in Python 2.3, a :class:`BaseHandler` subclass may also change its
+ :attr:`handler_order` member variable to modify its position in the handlers
+ list.
+
+The following exceptions are raised as appropriate:
+
+
+.. exception:: URLError
+
+ The handlers raise this exception (or derived exceptions) when they run into a
+ problem. It is a subclass of :exc:`IOError`.
+
+
+.. exception:: HTTPError
+
+ A subclass of :exc:`URLError`, it can also function as a non-exceptional
+ file-like return value (the same thing that :func:`urlopen` returns). This
+ is useful when handling exotic HTTP errors, such as requests for
+ authentication.
+
+The following classes are provided:
+
+
+.. class:: Request(url[, data][, headers] [, origin_req_host][, unverifiable])
+
+ This class is an abstraction of a URL request.
+
+ *url* should be a string containing a valid URL.
+
+ *data* may be a string specifying additional data to send to the server, or
+ ``None`` if no such data is needed. Currently HTTP requests are the only ones
+ that use *data*; the HTTP request will be a POST instead of a GET when the
+ *data* parameter is provided. *data* should be a buffer in the standard
+ :mimetype:`application/x-www-form-urlencoded` format. The
+ :func:`urllib.urlencode` function takes a mapping or sequence of 2-tuples and
+ returns a string in this format.
+
+ *headers* should be a dictionary, and will be treated as if :meth:`add_header`
+ was called with each key and value as arguments.
+
+ The final two arguments are only of interest for correct handling of third-party
+ HTTP cookies:
+
+ *origin_req_host* should be the request-host of the origin transaction, as
+ defined by :rfc:`2965`. It defaults to ``cookielib.request_host(self)``. This
+ is the host name or IP address of the original request that was initiated by the
+ user. For example, if the request is for an image in an HTML document, this
+ should be the request-host of the request for the page containing the image.
+
+ *unverifiable* should indicate whether the request is unverifiable, as defined
+ by RFC 2965. It defaults to False. An unverifiable request is one whose URL
+ the user did not have the option to approve. For example, if the request is for
+ an image in an HTML document, and the user had no option to approve the
+ automatic fetching of the image, this should be true.
+
+
+.. class:: OpenerDirector()
+
+ The :class:`OpenerDirector` class opens URLs via :class:`BaseHandler`\ s chained
+ together. It manages the chaining of handlers, and recovery from errors.
+
+
+.. class:: BaseHandler()
+
+ This is the base class for all registered handlers --- and handles only the
+ simple mechanics of registration.
+
+
+.. class:: HTTPDefaultErrorHandler()
+
+ A class which defines a default handler for HTTP error responses; all responses
+ are turned into :exc:`HTTPError` exceptions.
+
+
+.. class:: HTTPRedirectHandler()
+
+ A class to handle redirections.
+
+
+.. class:: HTTPCookieProcessor([cookiejar])
+
+ A class to handle HTTP Cookies.
+
+
+.. class:: ProxyHandler([proxies])
+
+ Cause requests to go through a proxy. If *proxies* is given, it must be a
+ dictionary mapping protocol names to URLs of proxies. The default is to read the
+ list of proxies from the environment variables :envvar:`<protocol>_proxy`.
+
+
+.. class:: HTTPPasswordMgr()
+
+ Keep a database of ``(realm, uri) -> (user, password)`` mappings.
+
+
+.. class:: HTTPPasswordMgrWithDefaultRealm()
+
+ Keep a database of ``(realm, uri) -> (user, password)`` mappings. A realm of
+ ``None`` is considered a catch-all realm, which is searched if no other realm
+ fits.
+
+
+.. class:: AbstractBasicAuthHandler([password_mgr])
+
+ This is a mixin class that helps with HTTP authentication, both to the remote
+ host and to a proxy. *password_mgr*, if given, should be something that is
+ compatible with :class:`HTTPPasswordMgr`; refer to section
+ :ref:`http-password-mgr` for information on the interface that must be
+ supported.
+
+
+.. class:: HTTPBasicAuthHandler([password_mgr])
+
+ Handle authentication with the remote host. *password_mgr*, if given, should be
+ something that is compatible with :class:`HTTPPasswordMgr`; refer to section
+ :ref:`http-password-mgr` for information on the interface that must be
+ supported.
+
+
+.. class:: ProxyBasicAuthHandler([password_mgr])
+
+ Handle authentication with the proxy. *password_mgr*, if given, should be
+ something that is compatible with :class:`HTTPPasswordMgr`; refer to section
+ :ref:`http-password-mgr` for information on the interface that must be
+ supported.
+
+
+.. class:: AbstractDigestAuthHandler([password_mgr])
+
+ This is a mixin class that helps with HTTP authentication, both to the remote
+ host and to a proxy. *password_mgr*, if given, should be something that is
+ compatible with :class:`HTTPPasswordMgr`; refer to section
+ :ref:`http-password-mgr` for information on the interface that must be
+ supported.
+
+
+.. class:: HTTPDigestAuthHandler([password_mgr])
+
+ Handle authentication with the remote host. *password_mgr*, if given, should be
+ something that is compatible with :class:`HTTPPasswordMgr`; refer to section
+ :ref:`http-password-mgr` for information on the interface that must be
+ supported.
+
+
+.. class:: ProxyDigestAuthHandler([password_mgr])
+
+ Handle authentication with the proxy. *password_mgr*, if given, should be
+ something that is compatible with :class:`HTTPPasswordMgr`; refer to section
+ :ref:`http-password-mgr` for information on the interface that must be
+ supported.
+
+
+.. class:: HTTPHandler()
+
+ A class to handle opening of HTTP URLs.
+
+
+.. class:: HTTPSHandler()
+
+ A class to handle opening of HTTPS URLs.
+
+
+.. class:: FileHandler()
+
+ Open local files.
+
+
+.. class:: FTPHandler()
+
+ Open FTP URLs.
+
+
+.. class:: CacheFTPHandler()
+
+ Open FTP URLs, keeping a cache of open FTP connections to minimize delays.
+
+
+.. class:: UnknownHandler()
+
+ A catch-all class to handle unknown URLs.
+
+
+.. _request-objects:
+
+Request Objects
+---------------
+
+The following methods describe all of :class:`Request`'s public interface, and
+so all must be overridden in subclasses.
+
+
+.. method:: Request.add_data(data)
+
+ Set the :class:`Request` data to *data*. This is ignored by all handlers except
+ HTTP handlers --- and there it should be a byte string, and will change the
+ request to be ``POST`` rather than ``GET``.
+
+
+.. method:: Request.get_method()
+
+ Return a string indicating the HTTP request method. This is only meaningful for
+ HTTP requests, and currently always returns ``'GET'`` or ``'POST'``.
+
+
+.. method:: Request.has_data()
+
+ Return whether the instance has a non-\ ``None`` data.
+
+
+.. method:: Request.get_data()
+
+ Return the instance's data.
+
+
+.. method:: Request.add_header(key, val)
+
+ Add another header to the request. Headers are currently ignored by all
+ handlers except HTTP handlers, where they are added to the list of headers sent
+ to the server. Note that there cannot be more than one header with the same
+ name, and later calls will overwrite previous calls in case the *key* collides.
+ Currently, this is no loss of HTTP functionality, since all headers which have
+ meaning when used more than once have a (header-specific) way of gaining the
+ same functionality using only one header.
+
+
+.. method:: Request.add_unredirected_header(key, header)
+
+ Add a header that will not be added to a redirected request.
+
+ .. versionadded:: 2.4
+
+
+.. method:: Request.has_header(header)
+
+ Return whether the instance has the named header (checks both regular and
+ unredirected).
+
+ .. versionadded:: 2.4
+
+
+.. method:: Request.get_full_url()
+
+ Return the URL given in the constructor.
+
+
+.. method:: Request.get_type()
+
+ Return the type of the URL --- also known as the scheme.
+
+
+.. method:: Request.get_host()
+
+ Return the host to which a connection will be made.
+
+
+.. method:: Request.get_selector()
+
+ Return the selector --- the part of the URL that is sent to the server.
+
+
+.. method:: Request.set_proxy(host, type)
+
+ Prepare the request by connecting to a proxy server. The *host* and *type* will
+ replace those of the instance, and the instance's selector will be the original
+ URL given in the constructor.
+
+
+.. method:: Request.get_origin_req_host()
+
+ Return the request-host of the origin transaction, as defined by :rfc:`2965`.
+ See the documentation for the :class:`Request` constructor.
+
+
+.. method:: Request.is_unverifiable()
+
+ Return whether the request is unverifiable, as defined by RFC 2965. See the
+ documentation for the :class:`Request` constructor.
+
+
+.. _opener-director-objects:
+
+OpenerDirector Objects
+----------------------
+
+:class:`OpenerDirector` instances have the following methods:
+
+
+.. method:: OpenerDirector.add_handler(handler)
+
+ *handler* should be an instance of :class:`BaseHandler`. The following methods
+ are searched, and added to the possible chains (note that HTTP errors are a
+ special case).
+
+ * :meth:`protocol_open` --- signal that the handler knows how to open *protocol*
+ URLs.
+
+ * :meth:`http_error_type` --- signal that the handler knows how to handle HTTP
+ errors with HTTP error code *type*.
+
+ * :meth:`protocol_error` --- signal that the handler knows how to handle errors
+ from (non-\ ``http``) *protocol*.
+
+ * :meth:`protocol_request` --- signal that the handler knows how to pre-process
+ *protocol* requests.
+
+ * :meth:`protocol_response` --- signal that the handler knows how to
+ post-process *protocol* responses.
+
+
+.. method:: OpenerDirector.open(url[, data][, timeout])
+
+ Open the given *url* (which can be a request object or a string), optionally
+ passing the given *data*. Arguments, return values and exceptions raised are the
+ same as those of :func:`urlopen` (which simply calls the :meth:`open` method on
+ the currently installed global :class:`OpenerDirector`). The optional *timeout*
+ parameter specifies a timeout in seconds for the connection attempt (if not
+ specified, or passed as None, the global default timeout setting will be used;
+ this actually only work for HTTP, HTTPS, FTP and FTPS connections).
+
+ .. versionchanged:: 2.6
+ *timeout* was added.
+
+
+.. method:: OpenerDirector.error(proto[, arg[, ...]])
+
+ Handle an error of the given protocol. This will call the registered error
+ handlers for the given protocol with the given arguments (which are protocol
+ specific). The HTTP protocol is a special case which uses the HTTP response
+ code to determine the specific error handler; refer to the :meth:`http_error_\*`
+ methods of the handler classes.
+
+ Return values and exceptions raised are the same as those of :func:`urlopen`.
+
+OpenerDirector objects open URLs in three stages:
+
+The order in which these methods are called within each stage is determined by
+sorting the handler instances.
+
+#. Every handler with a method named like :meth:`protocol_request` has that
+ method called to pre-process the request.
+
+#. Handlers with a method named like :meth:`protocol_open` are called to handle
+ the request. This stage ends when a handler either returns a non-\ :const:`None`
+ value (ie. a response), or raises an exception (usually :exc:`URLError`).
+ Exceptions are allowed to propagate.
+
+ In fact, the above algorithm is first tried for methods named
+ :meth:`default_open`. If all such methods return :const:`None`, the algorithm
+ is repeated for methods named like :meth:`protocol_open`. If all such methods
+ return :const:`None`, the algorithm is repeated for methods named
+ :meth:`unknown_open`.
+
+ Note that the implementation of these methods may involve calls of the parent
+ :class:`OpenerDirector` instance's :meth:`.open` and :meth:`.error` methods.
+
+#. Every handler with a method named like :meth:`protocol_response` has that
+ method called to post-process the response.
+
+
+.. _base-handler-objects:
+
+BaseHandler Objects
+-------------------
+
+:class:`BaseHandler` objects provide a couple of methods that are directly
+useful, and others that are meant to be used by derived classes. These are
+intended for direct use:
+
+
+.. method:: BaseHandler.add_parent(director)
+
+ Add a director as parent.
+
+
+.. method:: BaseHandler.close()
+
+ Remove any parents.
+
+The following members and methods should only be used by classes derived from
+:class:`BaseHandler`.
+
+.. note::
+
+ The convention has been adopted that subclasses defining
+ :meth:`protocol_request` or :meth:`protocol_response` methods are named
+ :class:`\*Processor`; all others are named :class:`\*Handler`.
+
+
+.. attribute:: BaseHandler.parent
+
+ A valid :class:`OpenerDirector`, which can be used to open using a different
+ protocol, or handle errors.
+
+
+.. method:: BaseHandler.default_open(req)
+
+ This method is *not* defined in :class:`BaseHandler`, but subclasses should
+ define it if they want to catch all URLs.
+
+ This method, if implemented, will be called by the parent
+ :class:`OpenerDirector`. It should return a file-like object as described in
+ the return value of the :meth:`open` of :class:`OpenerDirector`, or ``None``.
+ It should raise :exc:`URLError`, unless a truly exceptional thing happens (for
+ example, :exc:`MemoryError` should not be mapped to :exc:`URLError`).
+
+ This method will be called before any protocol-specific open method.
+
+
+.. method:: BaseHandler.protocol_open(req)
+ :noindex:
+
+ This method is *not* defined in :class:`BaseHandler`, but subclasses should
+ define it if they want to handle URLs with the given protocol.
+
+ This method, if defined, will be called by the parent :class:`OpenerDirector`.
+ Return values should be the same as for :meth:`default_open`.
+
+
+.. method:: BaseHandler.unknown_open(req)
+
+ This method is *not* defined in :class:`BaseHandler`, but subclasses should
+ define it if they want to catch all URLs with no specific registered handler to
+ open it.
+
+ This method, if implemented, will be called by the :attr:`parent`
+ :class:`OpenerDirector`. Return values should be the same as for
+ :meth:`default_open`.
+
+
+.. method:: BaseHandler.http_error_default(req, fp, code, msg, hdrs)
+
+ This method is *not* defined in :class:`BaseHandler`, but subclasses should
+ override it if they intend to provide a catch-all for otherwise unhandled HTTP
+ errors. It will be called automatically by the :class:`OpenerDirector` getting
+ the error, and should not normally be called in other circumstances.
+
+ *req* will be a :class:`Request` object, *fp* will be a file-like object with
+ the HTTP error body, *code* will be the three-digit code of the error, *msg*
+ will be the user-visible explanation of the code and *hdrs* will be a mapping
+ object with the headers of the error.
+
+ Return values and exceptions raised should be the same as those of
+ :func:`urlopen`.
+
+
+.. method:: BaseHandler.http_error_nnn(req, fp, code, msg, hdrs)
+
+ *nnn* should be a three-digit HTTP error code. This method is also not defined
+ in :class:`BaseHandler`, but will be called, if it exists, on an instance of a
+ subclass, when an HTTP error with code *nnn* occurs.
+
+ Subclasses should override this method to handle specific HTTP errors.
+
+ Arguments, return values and exceptions raised should be the same as for
+ :meth:`http_error_default`.
+
+
+.. method:: BaseHandler.protocol_request(req)
+ :noindex:
+
+ This method is *not* defined in :class:`BaseHandler`, but subclasses should
+ define it if they want to pre-process requests of the given protocol.
+
+ This method, if defined, will be called by the parent :class:`OpenerDirector`.
+ *req* will be a :class:`Request` object. The return value should be a
+ :class:`Request` object.
+
+
+.. method:: BaseHandler.protocol_response(req, response)
+ :noindex:
+
+ This method is *not* defined in :class:`BaseHandler`, but subclasses should
+ define it if they want to post-process responses of the given protocol.
+
+ This method, if defined, will be called by the parent :class:`OpenerDirector`.
+ *req* will be a :class:`Request` object. *response* will be an object
+ implementing the same interface as the return value of :func:`urlopen`. The
+ return value should implement the same interface as the return value of
+ :func:`urlopen`.
+
+
+.. _http-redirect-handler:
+
+HTTPRedirectHandler Objects
+---------------------------
+
+.. note::
+
+ Some HTTP redirections require action from this module's client code. If this
+ is the case, :exc:`HTTPError` is raised. See :rfc:`2616` for details of the
+ precise meanings of the various redirection codes.
+
+
+.. method:: HTTPRedirectHandler.redirect_request(req, fp, code, msg, hdrs)
+
+ Return a :class:`Request` or ``None`` in response to a redirect. This is called
+ by the default implementations of the :meth:`http_error_30\*` methods when a
+ redirection is received from the server. If a redirection should take place,
+ return a new :class:`Request` to allow :meth:`http_error_30\*` to perform the
+ redirect. Otherwise, raise :exc:`HTTPError` if no other handler should try to
+ handle this URL, or return ``None`` if you can't but another handler might.
+
+ .. note::
+
+ The default implementation of this method does not strictly follow :rfc:`2616`,
+ which says that 301 and 302 responses to ``POST`` requests must not be
+ automatically redirected without confirmation by the user. In reality, browsers
+ do allow automatic redirection of these responses, changing the POST to a
+ ``GET``, and the default implementation reproduces this behavior.
+
+
+.. method:: HTTPRedirectHandler.http_error_301(req, fp, code, msg, hdrs)
+
+ Redirect to the ``Location:`` URL. This method is called by the parent
+ :class:`OpenerDirector` when getting an HTTP 'moved permanently' response.
+
+
+.. method:: HTTPRedirectHandler.http_error_302(req, fp, code, msg, hdrs)
+
+ The same as :meth:`http_error_301`, but called for the 'found' response.
+
+
+.. method:: HTTPRedirectHandler.http_error_303(req, fp, code, msg, hdrs)
+
+ The same as :meth:`http_error_301`, but called for the 'see other' response.
+
+
+.. method:: HTTPRedirectHandler.http_error_307(req, fp, code, msg, hdrs)
+
+ The same as :meth:`http_error_301`, but called for the 'temporary redirect'
+ response.
+
+
+.. _http-cookie-processor:
+
+HTTPCookieProcessor Objects
+---------------------------
+
+.. versionadded:: 2.4
+
+:class:`HTTPCookieProcessor` instances have one attribute:
+
+
+.. attribute:: HTTPCookieProcessor.cookiejar
+
+ The :class:`cookielib.CookieJar` in which cookies are stored.
+
+
+.. _proxy-handler:
+
+ProxyHandler Objects
+--------------------
+
+
+.. method:: ProxyHandler.protocol_open(request)
+ :noindex:
+
+ The :class:`ProxyHandler` will have a method :meth:`protocol_open` for every
+ *protocol* which has a proxy in the *proxies* dictionary given in the
+ constructor. The method will modify requests to go through the proxy, by
+ calling ``request.set_proxy()``, and call the next handler in the chain to
+ actually execute the protocol.
+
+
+.. _http-password-mgr:
+
+HTTPPasswordMgr Objects
+-----------------------
+
+These methods are available on :class:`HTTPPasswordMgr` and
+:class:`HTTPPasswordMgrWithDefaultRealm` objects.
+
+
+.. method:: HTTPPasswordMgr.add_password(realm, uri, user, passwd)
+
+ *uri* can be either a single URI, or a sequence of URIs. *realm*, *user* and
+ *passwd* must be strings. This causes ``(user, passwd)`` to be used as
+ authentication tokens when authentication for *realm* and a super-URI of any of
+ the given URIs is given.
+
+
+.. method:: HTTPPasswordMgr.find_user_password(realm, authuri)
+
+ Get user/password for given realm and URI, if any. This method will return
+ ``(None, None)`` if there is no matching user/password.
+
+ For :class:`HTTPPasswordMgrWithDefaultRealm` objects, the realm ``None`` will be
+ searched if the given *realm* has no matching user/password.
+
+
+.. _abstract-basic-auth-handler:
+
+AbstractBasicAuthHandler Objects
+--------------------------------
+
+
+.. method:: AbstractBasicAuthHandler.http_error_auth_reqed(authreq, host, req, headers)
+
+ Handle an authentication request by getting a user/password pair, and re-trying
+ the request. *authreq* should be the name of the header where the information
+ about the realm is included in the request, *host* specifies the URL and path to
+ authenticate for, *req* should be the (failed) :class:`Request` object, and
+ *headers* should be the error headers.
+
+ *host* is either an authority (e.g. ``"python.org"``) or a URL containing an
+ authority component (e.g. ``"http://python.org/"``). In either case, the
+ authority must not contain a userinfo component (so, ``"python.org"`` and
+ ``"python.org:80"`` are fine, ``"joe:password@python.org"`` is not).
+
+
+.. _http-basic-auth-handler:
+
+HTTPBasicAuthHandler Objects
+----------------------------
+
+
+.. method:: HTTPBasicAuthHandler.http_error_401(req, fp, code, msg, hdrs)
+
+ Retry the request with authentication information, if available.
+
+
+.. _proxy-basic-auth-handler:
+
+ProxyBasicAuthHandler Objects
+-----------------------------
+
+
+.. method:: ProxyBasicAuthHandler.http_error_407(req, fp, code, msg, hdrs)
+
+ Retry the request with authentication information, if available.
+
+
+.. _abstract-digest-auth-handler:
+
+AbstractDigestAuthHandler Objects
+---------------------------------
+
+
+.. method:: AbstractDigestAuthHandler.http_error_auth_reqed(authreq, host, req, headers)
+
+ *authreq* should be the name of the header where the information about the realm
+ is included in the request, *host* should be the host to authenticate to, *req*
+ should be the (failed) :class:`Request` object, and *headers* should be the
+ error headers.
+
+
+.. _http-digest-auth-handler:
+
+HTTPDigestAuthHandler Objects
+-----------------------------
+
+
+.. method:: HTTPDigestAuthHandler.http_error_401(req, fp, code, msg, hdrs)
+
+ Retry the request with authentication information, if available.
+
+
+.. _proxy-digest-auth-handler:
+
+ProxyDigestAuthHandler Objects
+------------------------------
+
+
+.. method:: ProxyDigestAuthHandler.http_error_407(req, fp, code, msg, hdrs)
+
+ Retry the request with authentication information, if available.
+
+
+.. _http-handler-objects:
+
+HTTPHandler Objects
+-------------------
+
+
+.. method:: HTTPHandler.http_open(req)
+
+ Send an HTTP request, which can be either GET or POST, depending on
+ ``req.has_data()``.
+
+
+.. _https-handler-objects:
+
+HTTPSHandler Objects
+--------------------
+
+
+.. method:: HTTPSHandler.https_open(req)
+
+ Send an HTTPS request, which can be either GET or POST, depending on
+ ``req.has_data()``.
+
+
+.. _file-handler-objects:
+
+FileHandler Objects
+-------------------
+
+
+.. method:: FileHandler.file_open(req)
+
+ Open the file locally, if there is no host name, or the host name is
+ ``'localhost'``. Change the protocol to ``ftp`` otherwise, and retry opening it
+ using :attr:`parent`.
+
+
+.. _ftp-handler-objects:
+
+FTPHandler Objects
+------------------
+
+
+.. method:: FTPHandler.ftp_open(req)
+
+ Open the FTP file indicated by *req*. The login is always done with empty
+ username and password.
+
+
+.. _cacheftp-handler-objects:
+
+CacheFTPHandler Objects
+-----------------------
+
+:class:`CacheFTPHandler` objects are :class:`FTPHandler` objects with the
+following additional methods:
+
+
+.. method:: CacheFTPHandler.setTimeout(t)
+
+ Set timeout of connections to *t* seconds.
+
+
+.. method:: CacheFTPHandler.setMaxConns(m)
+
+ Set maximum number of cached connections to *m*.
+
+
+.. _unknown-handler-objects:
+
+UnknownHandler Objects
+----------------------
+
+
+.. method:: UnknownHandler.unknown_open()
+
+ Raise a :exc:`URLError` exception.
+
+
+.. _http-error-processor-objects:
+
+HTTPErrorProcessor Objects
+--------------------------
+
+.. versionadded:: 2.4
+
+
+.. method:: HTTPErrorProcessor.unknown_open()
+
+ Process HTTP error responses.
+
+ For 200 error codes, the response object is returned immediately.
+
+ For non-200 error codes, this simply passes the job on to the
+ :meth:`protocol_error_code` handler methods, via :meth:`OpenerDirector.error`.
+ Eventually, :class:`urllib2.HTTPDefaultErrorHandler` will raise an
+ :exc:`HTTPError` if no other handler handles the error.
+
+
+.. _urllib2-examples:
+
+Examples
+--------
+
+This example gets the python.org main page and displays the first 100 bytes of
+it::
+
+ >>> import urllib2
+ >>> f = urllib2.urlopen('http://www.python.org/')
+ >>> print f.read(100)
+ <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+ <?xml-stylesheet href="./css/ht2html
+
+Here we are sending a data-stream to the stdin of a CGI and reading the data it
+returns to us. Note that this example will only work when the Python
+installation supports SSL. ::
+
+ >>> import urllib2
+ >>> req = urllib2.Request(url='https://localhost/cgi-bin/test.cgi',
+ ... data='This data is passed to stdin of the CGI')
+ >>> f = urllib2.urlopen(req)
+ >>> print f.read()
+ Got Data: "This data is passed to stdin of the CGI"
+
+The code for the sample CGI used in the above example is::
+
+ #!/usr/bin/env python
+ import sys
+ data = sys.stdin.read()
+ print 'Content-type: text-plain\n\nGot Data: "%s"' % data
+
+Use of Basic HTTP Authentication::
+
+ import urllib2
+ # Create an OpenerDirector with support for Basic HTTP Authentication...
+ auth_handler = urllib2.HTTPBasicAuthHandler()
+ auth_handler.add_password(realm='PDQ Application',
+ uri='https://mahler:8092/site-updates.py',
+ user='klem',
+ passwd='kadidd!ehopper')
+ opener = urllib2.build_opener(auth_handler)
+ # ...and install it globally so it can be used with urlopen.
+ urllib2.install_opener(opener)
+ urllib2.urlopen('http://www.example.com/login.html')
+
+:func:`build_opener` provides many handlers by default, including a
+:class:`ProxyHandler`. By default, :class:`ProxyHandler` uses the environment
+variables named ``<scheme>_proxy``, where ``<scheme>`` is the URL scheme
+involved. For example, the :envvar:`http_proxy` environment variable is read to
+obtain the HTTP proxy's URL.
+
+This example replaces the default :class:`ProxyHandler` with one that uses
+programatically-supplied proxy URLs, and adds proxy authorization support with
+:class:`ProxyBasicAuthHandler`. ::
+
+ proxy_handler = urllib2.ProxyHandler({'http': 'http://www.example.com:3128/'})
+ proxy_auth_handler = urllib2.HTTPBasicAuthHandler()
+ proxy_auth_handler.add_password('realm', 'host', 'username', 'password')
+
+ opener = build_opener(proxy_handler, proxy_auth_handler)
+ # This time, rather than install the OpenerDirector, we use it directly:
+ opener.open('http://www.example.com/login.html')
+
+Adding HTTP headers:
+
+Use the *headers* argument to the :class:`Request` constructor, or::
+
+ import urllib2
+ req = urllib2.Request('http://www.example.com/')
+ req.add_header('Referer', 'http://www.python.org/')
+ r = urllib2.urlopen(req)
+
+:class:`OpenerDirector` automatically adds a :mailheader:`User-Agent` header to
+every :class:`Request`. To change this::
+
+ import urllib2
+ opener = urllib2.build_opener()
+ opener.addheaders = [('User-agent', 'Mozilla/5.0')]
+ opener.open('http://www.example.com/')
+
+Also, remember that a few standard headers (:mailheader:`Content-Length`,
+:mailheader:`Content-Type` and :mailheader:`Host`) are added when the
+:class:`Request` is passed to :func:`urlopen` (or :meth:`OpenerDirector.open`).
+
diff --git a/Doc/library/urlparse.rst b/Doc/library/urlparse.rst
new file mode 100644
index 0000000000..c6bc82b7b5
--- /dev/null
+++ b/Doc/library/urlparse.rst
@@ -0,0 +1,268 @@
+:mod:`urlparse` --- Parse URLs into components
+==============================================
+
+.. module:: urlparse
+ :synopsis: Parse URLs into or assemble them from components.
+
+
+.. index::
+ single: WWW
+ single: World Wide Web
+ single: URL
+ pair: URL; parsing
+ pair: relative; URL
+
+This module defines a standard interface to break Uniform Resource Locator (URL)
+strings up in components (addressing scheme, network location, path etc.), to
+combine the components back into a URL string, and to convert a "relative URL"
+to an absolute URL given a "base URL."
+
+The module has been designed to match the Internet RFC on Relative Uniform
+Resource Locators (and discovered a bug in an earlier draft!). It supports the
+following URL schemes: ``file``, ``ftp``, ``gopher``, ``hdl``, ``http``,
+``https``, ``imap``, ``mailto``, ``mms``, ``news``, ``nntp``, ``prospero``,
+``rsync``, ``rtsp``, ``rtspu``, ``sftp``, ``shttp``, ``sip``, ``sips``,
+``snews``, ``svn``, ``svn+ssh``, ``telnet``, ``wais``.
+
+.. versionadded:: 2.5
+ Support for the ``sftp`` and ``sips`` schemes.
+
+The :mod:`urlparse` module defines the following functions:
+
+
+.. function:: urlparse(urlstring[, default_scheme[, allow_fragments]])
+
+ Parse a URL into six components, returning a 6-tuple. This corresponds to the
+ general structure of a URL: ``scheme://netloc/path;parameters?query#fragment``.
+ Each tuple item is a string, possibly empty. The components are not broken up in
+ smaller parts (for example, the network location is a single string), and %
+ escapes are not expanded. The delimiters as shown above are not part of the
+ result, except for a leading slash in the *path* component, which is retained if
+ present. For example::
+
+ >>> from urlparse import urlparse
+ >>> o = urlparse('http://www.cwi.nl:80/%7Eguido/Python.html')
+ >>> o
+ ('http', 'www.cwi.nl:80', '/%7Eguido/Python.html', '', '', '')
+ >>> o.scheme
+ 'http'
+ >>> o.port
+ 80
+ >>> o.geturl()
+ 'http://www.cwi.nl:80/%7Eguido/Python.html'
+
+ If the *default_scheme* argument is specified, it gives the default addressing
+ scheme, to be used only if the URL does not specify one. The default value for
+ this argument is the empty string.
+
+ If the *allow_fragments* argument is false, fragment identifiers are not
+ allowed, even if the URL's addressing scheme normally does support them. The
+ default value for this argument is :const:`True`.
+
+ The return value is actually an instance of a subclass of :class:`tuple`. This
+ class has the following additional read-only convenience attributes:
+
+ +------------------+-------+--------------------------+----------------------+
+ | Attribute | Index | Value | Value if not present |
+ +==================+=======+==========================+======================+
+ | :attr:`scheme` | 0 | URL scheme specifier | empty string |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`netloc` | 1 | Network location part | empty string |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`path` | 2 | Hierarchical path | empty string |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`params` | 3 | Parameters for last path | empty string |
+ | | | element | |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`query` | 4 | Query component | empty string |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`fragment` | 5 | Fragment identifier | empty string |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`username` | | User name | :const:`None` |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`password` | | Password | :const:`None` |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`hostname` | | Host name (lower case) | :const:`None` |
+ +------------------+-------+--------------------------+----------------------+
+ | :attr:`port` | | Port number as integer, | :const:`None` |
+ | | | if present | |
+ +------------------+-------+--------------------------+----------------------+
+
+ See section :ref:`urlparse-result-object` for more information on the result
+ object.
+
+ .. versionchanged:: 2.5
+ Added attributes to return value.
+
+
+.. function:: urlunparse(parts)
+
+ Construct a URL from a tuple as returned by ``urlparse()``. The *parts* argument
+ can be any six-item iterable. This may result in a slightly different, but
+ equivalent URL, if the URL that was parsed originally had unnecessary delimiters
+ (for example, a ? with an empty query; the RFC states that these are
+ equivalent).
+
+
+.. function:: urlsplit(urlstring[, default_scheme[, allow_fragments]])
+
+ This is similar to :func:`urlparse`, but does not split the params from the URL.
+ This should generally be used instead of :func:`urlparse` if the more recent URL
+ syntax allowing parameters to be applied to each segment of the *path* portion
+ of the URL (see :rfc:`2396`) is wanted. A separate function is needed to
+ separate the path segments and parameters. This function returns a 5-tuple:
+ (addressing scheme, network location, path, query, fragment identifier).
+
+ The return value is actually an instance of a subclass of :class:`tuple`. This
+ class has the following additional read-only convenience attributes:
+
+ +------------------+-------+-------------------------+----------------------+
+ | Attribute | Index | Value | Value if not present |
+ +==================+=======+=========================+======================+
+ | :attr:`scheme` | 0 | URL scheme specifier | empty string |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`netloc` | 1 | Network location part | empty string |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`path` | 2 | Hierarchical path | empty string |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`query` | 3 | Query component | empty string |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`fragment` | 4 | Fragment identifier | empty string |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`username` | | User name | :const:`None` |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`password` | | Password | :const:`None` |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`hostname` | | Host name (lower case) | :const:`None` |
+ +------------------+-------+-------------------------+----------------------+
+ | :attr:`port` | | Port number as integer, | :const:`None` |
+ | | | if present | |
+ +------------------+-------+-------------------------+----------------------+
+
+ See section :ref:`urlparse-result-object` for more information on the result
+ object.
+
+ .. versionadded:: 2.2
+
+ .. versionchanged:: 2.5
+ Added attributes to return value.
+
+
+.. function:: urlunsplit(parts)
+
+ Combine the elements of a tuple as returned by :func:`urlsplit` into a complete
+ URL as a string. The *parts* argument can be any five-item iterable. This may
+ result in a slightly different, but equivalent URL, if the URL that was parsed
+ originally had unnecessary delimiters (for example, a ? with an empty query; the
+ RFC states that these are equivalent).
+
+ .. versionadded:: 2.2
+
+
+.. function:: urljoin(base, url[, allow_fragments])
+
+ Construct a full ("absolute") URL by combining a "base URL" (*base*) with
+ another URL (*url*). Informally, this uses components of the base URL, in
+ particular the addressing scheme, the network location and (part of) the path,
+ to provide missing components in the relative URL. For example::
+
+ >>> from urlparse import urljoin
+ >>> urljoin('http://www.cwi.nl/%7Eguido/Python.html', 'FAQ.html')
+ 'http://www.cwi.nl/%7Eguido/FAQ.html'
+
+ The *allow_fragments* argument has the same meaning and default as for
+ :func:`urlparse`.
+
+ .. note::
+
+ If *url* is an absolute URL (that is, starting with ``//`` or ``scheme://``),
+ the *url*'s host name and/or scheme will be present in the result. For example:
+
+ ::
+
+ >>> urljoin('http://www.cwi.nl/%7Eguido/Python.html',
+ ... '//www.python.org/%7Eguido')
+ 'http://www.python.org/%7Eguido'
+
+ If you do not want that behavior, preprocess the *url* with :func:`urlsplit` and
+ :func:`urlunsplit`, removing possible *scheme* and *netloc* parts.
+
+
+.. function:: urldefrag(url)
+
+ If *url* contains a fragment identifier, returns a modified version of *url*
+ with no fragment identifier, and the fragment identifier as a separate string.
+ If there is no fragment identifier in *url*, returns *url* unmodified and an
+ empty string.
+
+
+.. seealso::
+
+ :rfc:`1738` - Uniform Resource Locators (URL)
+ This specifies the formal syntax and semantics of absolute URLs.
+
+ :rfc:`1808` - Relative Uniform Resource Locators
+ This Request For Comments includes the rules for joining an absolute and a
+ relative URL, including a fair number of "Abnormal Examples" which govern the
+ treatment of border cases.
+
+ :rfc:`2396` - Uniform Resource Identifiers (URI): Generic Syntax
+ Document describing the generic syntactic requirements for both Uniform Resource
+ Names (URNs) and Uniform Resource Locators (URLs).
+
+
+.. _urlparse-result-object:
+
+Results of :func:`urlparse` and :func:`urlsplit`
+------------------------------------------------
+
+The result objects from the :func:`urlparse` and :func:`urlsplit` functions are
+subclasses of the :class:`tuple` type. These subclasses add the attributes
+described in those functions, as well as provide an additional method:
+
+
+.. method:: ParseResult.geturl()
+
+ Return the re-combined version of the original URL as a string. This may differ
+ from the original URL in that the scheme will always be normalized to lower case
+ and empty components may be dropped. Specifically, empty parameters, queries,
+ and fragment identifiers will be removed.
+
+ The result of this method is a fixpoint if passed back through the original
+ parsing function::
+
+ >>> import urlparse
+ >>> url = 'HTTP://www.Python.org/doc/#'
+
+ >>> r1 = urlparse.urlsplit(url)
+ >>> r1.geturl()
+ 'http://www.Python.org/doc/'
+
+ >>> r2 = urlparse.urlsplit(r1.geturl())
+ >>> r2.geturl()
+ 'http://www.Python.org/doc/'
+
+ .. versionadded:: 2.5
+
+The following classes provide the implementations of the parse results::
+
+
+.. class:: BaseResult
+
+ Base class for the concrete result classes. This provides most of the attribute
+ definitions. It does not provide a :meth:`geturl` method. It is derived from
+ :class:`tuple`, but does not override the :meth:`__init__` or :meth:`__new__`
+ methods.
+
+
+.. class:: ParseResult(scheme, netloc, path, params, query, fragment)
+
+ Concrete class for :func:`urlparse` results. The :meth:`__new__` method is
+ overridden to support checking that the right number of arguments are passed.
+
+
+.. class:: SplitResult(scheme, netloc, path, query, fragment)
+
+ Concrete class for :func:`urlsplit` results. The :meth:`__new__` method is
+ overridden to support checking that the right number of arguments are passed.
+
diff --git a/Doc/library/user.rst b/Doc/library/user.rst
new file mode 100644
index 0000000000..ba9426210a
--- /dev/null
+++ b/Doc/library/user.rst
@@ -0,0 +1,69 @@
+
+:mod:`user` --- User-specific configuration hook
+================================================
+
+.. module:: user
+ :synopsis: A standard way to reference user-specific modules.
+
+
+.. index::
+ pair: .pythonrc.py; file
+ triple: user; configuration; file
+
+As a policy, Python doesn't run user-specified code on startup of Python
+programs. (Only interactive sessions execute the script specified in the
+:envvar:`PYTHONSTARTUP` environment variable if it exists).
+
+However, some programs or sites may find it convenient to allow users to have a
+standard customization file, which gets run when a program requests it. This
+module implements such a mechanism. A program that wishes to use the mechanism
+must execute the statement ::
+
+ import user
+
+.. index:: builtin: exec
+
+The :mod:`user` module looks for a file :file:`.pythonrc.py` in the user's home
+directory and if it can be opened, executes it (using :func:`exec`) in its
+own (the module :mod:`user`'s) global namespace. Errors during this phase are
+not caught; that's up to the program that imports the :mod:`user` module, if it
+wishes. The home directory is assumed to be named by the :envvar:`HOME`
+environment variable; if this is not set, the current directory is used.
+
+The user's :file:`.pythonrc.py` could conceivably test for ``sys.version`` if it
+wishes to do different things depending on the Python version.
+
+A warning to users: be very conservative in what you place in your
+:file:`.pythonrc.py` file. Since you don't know which programs will use it,
+changing the behavior of standard modules or functions is generally not a good
+idea.
+
+A suggestion for programmers who wish to use this mechanism: a simple way to let
+users specify options for your package is to have them define variables in their
+:file:`.pythonrc.py` file that you test in your module. For example, a module
+:mod:`spam` that has a verbosity level can look for a variable
+``user.spam_verbose``, as follows::
+
+ import user
+
+ verbose = bool(getattr(user, "spam_verbose", 0))
+
+(The three-argument form of :func:`getattr` is used in case the user has not
+defined ``spam_verbose`` in their :file:`.pythonrc.py` file.)
+
+Programs with extensive customization needs are better off reading a
+program-specific customization file.
+
+Programs with security or privacy concerns should *not* import this module; a
+user can easily break into a program by placing arbitrary code in the
+:file:`.pythonrc.py` file.
+
+Modules for general use should *not* import this module; it may interfere with
+the operation of the importing program.
+
+
+.. seealso::
+
+ Module :mod:`site`
+ Site-wide customization mechanism.
+
diff --git a/Doc/library/userdict.rst b/Doc/library/userdict.rst
new file mode 100644
index 0000000000..11d46ed109
--- /dev/null
+++ b/Doc/library/userdict.rst
@@ -0,0 +1,188 @@
+
+:mod:`UserDict` --- Class wrapper for dictionary objects
+========================================================
+
+.. module:: UserDict
+ :synopsis: Class wrapper for dictionary objects.
+
+
+The module defines a mixin, :class:`DictMixin`, defining all dictionary methods
+for classes that already have a minimum mapping interface. This greatly
+simplifies writing classes that need to be substitutable for dictionaries (such
+as the shelve module).
+
+This also module defines a class, :class:`UserDict`, that acts as a wrapper
+around dictionary objects. The need for this class has been largely supplanted
+by the ability to subclass directly from :class:`dict` (a feature that became
+available starting with Python version 2.2). Prior to the introduction of
+:class:`dict`, the :class:`UserDict` class was used to create dictionary-like
+sub-classes that obtained new behaviors by overriding existing methods or adding
+new ones.
+
+The :mod:`UserDict` module defines the :class:`UserDict` class and
+:class:`DictMixin`:
+
+
+.. class:: UserDict([initialdata])
+
+ Class that simulates a dictionary. The instance's contents are kept in a
+ regular dictionary, which is accessible via the :attr:`data` attribute of
+ :class:`UserDict` instances. If *initialdata* is provided, :attr:`data` is
+ initialized with its contents; note that a reference to *initialdata* will not
+ be kept, allowing it be used for other purposes.
+
+ .. note::
+
+ For backward compatibility, instances of :class:`UserDict` are not iterable.
+
+
+.. class:: IterableUserDict([initialdata])
+
+ Subclass of :class:`UserDict` that supports direct iteration (e.g. ``for key in
+ myDict``).
+
+In addition to supporting the methods and operations of mappings (see section
+:ref:`typesmapping`), :class:`UserDict` and :class:`IterableUserDict` instances
+provide the following attribute:
+
+
+.. attribute:: IterableUserDict.data
+
+ A real dictionary used to store the contents of the :class:`UserDict` class.
+
+
+.. class:: DictMixin()
+
+ Mixin defining all dictionary methods for classes that already have a minimum
+ dictionary interface including :meth:`__getitem__`, :meth:`__setitem__`,
+ :meth:`__delitem__`, and :meth:`keys`.
+
+ This mixin should be used as a superclass. Adding each of the above methods
+ adds progressively more functionality. For instance, defining all but
+ :meth:`__delitem__` will preclude only :meth:`pop` and :meth:`popitem` from the
+ full interface.
+
+ In addition to the four base methods, progressively more efficiency comes with
+ defining :meth:`__contains__`, :meth:`__iter__`, and :meth:`iteritems`.
+
+ Since the mixin has no knowledge of the subclass constructor, it does not define
+ :meth:`__init__` or :meth:`copy`.
+
+
+:mod:`UserList` --- Class wrapper for list objects
+==================================================
+
+.. module:: UserList
+ :synopsis: Class wrapper for list objects.
+
+
+.. note::
+
+ This module is available for backward compatibility only. If you are writing
+ code that does not need to work with versions of Python earlier than Python 2.2,
+ please consider subclassing directly from the built-in :class:`list` type.
+
+This module defines a class that acts as a wrapper around list objects. It is a
+useful base class for your own list-like classes, which can inherit from them
+and override existing methods or add new ones. In this way one can add new
+behaviors to lists.
+
+The :mod:`UserList` module defines the :class:`UserList` class:
+
+
+.. class:: UserList([list])
+
+ Class that simulates a list. The instance's contents are kept in a regular
+ list, which is accessible via the :attr:`data` attribute of :class:`UserList`
+ instances. The instance's contents are initially set to a copy of *list*,
+ defaulting to the empty list ``[]``. *list* can be any iterable, e.g. a
+ real Python list or a :class:`UserList` object.
+
+In addition to supporting the methods and operations of mutable sequences (see
+section :ref:`typesseq`), :class:`UserList` instances provide the following
+attribute:
+
+
+.. attribute:: UserList.data
+
+ A real Python list object used to store the contents of the :class:`UserList`
+ class.
+
+**Subclassing requirements:** Subclasses of :class:`UserList` are expect to
+offer a constructor which can be called with either no arguments or one
+argument. List operations which return a new sequence attempt to create an
+instance of the actual implementation class. To do so, it assumes that the
+constructor can be called with a single parameter, which is a sequence object
+used as a data source.
+
+If a derived class does not wish to comply with this requirement, all of the
+special methods supported by this class will need to be overridden; please
+consult the sources for information about the methods which need to be provided
+in that case.
+
+.. versionchanged:: 2.0
+ Python versions 1.5.2 and 1.6 also required that the constructor be callable
+ with no parameters, and offer a mutable :attr:`data` attribute. Earlier
+ versions of Python did not attempt to create instances of the derived class.
+
+
+:mod:`UserString` --- Class wrapper for string objects
+======================================================
+
+.. module:: UserString
+ :synopsis: Class wrapper for string objects.
+.. moduleauthor:: Peter Funk <pf@artcom-gmbh.de>
+.. sectionauthor:: Peter Funk <pf@artcom-gmbh.de>
+
+
+.. note::
+
+ This :class:`UserString` class from this module is available for backward
+ compatibility only. If you are writing code that does not need to work with
+ versions of Python earlier than Python 2.2, please consider subclassing directly
+ from the built-in :class:`str` type instead of using :class:`UserString` (there
+ is no built-in equivalent to :class:`MutableString`).
+
+This module defines a class that acts as a wrapper around string objects. It is
+a useful base class for your own string-like classes, which can inherit from
+them and override existing methods or add new ones. In this way one can add new
+behaviors to strings.
+
+It should be noted that these classes are highly inefficient compared to real
+string or Unicode objects; this is especially the case for
+:class:`MutableString`.
+
+The :mod:`UserString` module defines the following classes:
+
+
+.. class:: UserString([sequence])
+
+ Class that simulates a string or a Unicode string object. The instance's
+ content is kept in a regular string or Unicode string object, which is
+ accessible via the :attr:`data` attribute of :class:`UserString` instances. The
+ instance's contents are initially set to a copy of *sequence*. *sequence* can
+ be either a regular Python string or Unicode string, an instance of
+ :class:`UserString` (or a subclass) or an arbitrary sequence which can be
+ converted into a string using the built-in :func:`str` function.
+
+
+.. class:: MutableString([sequence])
+
+ This class is derived from the :class:`UserString` above and redefines strings
+ to be *mutable*. Mutable strings can't be used as dictionary keys, because
+ dictionaries require *immutable* objects as keys. The main intention of this
+ class is to serve as an educational example for inheritance and necessity to
+ remove (override) the :meth:`__hash__` method in order to trap attempts to use a
+ mutable object as dictionary key, which would be otherwise very error prone and
+ hard to track down.
+
+In addition to supporting the methods and operations of string and Unicode
+objects (see section :ref:`string-methods`), :class:`UserString` instances
+provide the following attribute:
+
+
+.. attribute:: MutableString.data
+
+ A real Python string or Unicode object used to store the content of the
+ :class:`UserString` class.
+
diff --git a/Doc/library/uu.rst b/Doc/library/uu.rst
new file mode 100644
index 0000000000..e2303c37f0
--- /dev/null
+++ b/Doc/library/uu.rst
@@ -0,0 +1,60 @@
+
+:mod:`uu` --- Encode and decode uuencode files
+==============================================
+
+.. module:: uu
+ :synopsis: Encode and decode files in uuencode format.
+.. moduleauthor:: Lance Ellinghouse
+
+
+This module encodes and decodes files in uuencode format, allowing arbitrary
+binary data to be transferred over ASCII-only connections. Wherever a file
+argument is expected, the methods accept a file-like object. For backwards
+compatibility, a string containing a pathname is also accepted, and the
+corresponding file will be opened for reading and writing; the pathname ``'-'``
+is understood to mean the standard input or output. However, this interface is
+deprecated; it's better for the caller to open the file itself, and be sure
+that, when required, the mode is ``'rb'`` or ``'wb'`` on Windows.
+
+.. index::
+ single: Jansen, Jack
+ single: Ellinghouse, Lance
+
+This code was contributed by Lance Ellinghouse, and modified by Jack Jansen.
+
+The :mod:`uu` module defines the following functions:
+
+
+.. function:: encode(in_file, out_file[, name[, mode]])
+
+ Uuencode file *in_file* into file *out_file*. The uuencoded file will have the
+ header specifying *name* and *mode* as the defaults for the results of decoding
+ the file. The default defaults are taken from *in_file*, or ``'-'`` and ``0666``
+ respectively.
+
+
+.. function:: decode(in_file[, out_file[, mode[, quiet]]])
+
+ This call decodes uuencoded file *in_file* placing the result on file
+ *out_file*. If *out_file* is a pathname, *mode* is used to set the permission
+ bits if the file must be created. Defaults for *out_file* and *mode* are taken
+ from the uuencode header. However, if the file specified in the header already
+ exists, a :exc:`uu.Error` is raised.
+
+ :func:`decode` may print a warning to standard error if the input was produced
+ by an incorrect uuencoder and Python could recover from that error. Setting
+ *quiet* to a true value silences this warning.
+
+
+.. exception:: Error()
+
+ Subclass of :exc:`Exception`, this can be raised by :func:`uu.decode` under
+ various situations, such as described above, but also including a badly
+ formatted header, or truncated input file.
+
+
+.. seealso::
+
+ Module :mod:`binascii`
+ Support module containing ASCII-to-binary and binary-to-ASCII conversions.
+
diff --git a/Doc/library/uuid.rst b/Doc/library/uuid.rst
new file mode 100644
index 0000000000..dd52638a78
--- /dev/null
+++ b/Doc/library/uuid.rst
@@ -0,0 +1,258 @@
+
+:mod:`uuid` --- UUID objects according to RFC 4122
+==================================================
+
+.. module:: uuid
+ :synopsis: UUID objects (universally unique identifiers) according to RFC 4122
+.. moduleauthor:: Ka-Ping Yee <ping@zesty.ca>
+.. sectionauthor:: George Yoshida <quiver@users.sourceforge.net>
+
+
+.. versionadded:: 2.5
+
+This module provides immutable :class:`UUID` objects (the :class:`UUID` class)
+and the functions :func:`uuid1`, :func:`uuid3`, :func:`uuid4`, :func:`uuid5` for
+generating version 1, 3, 4, and 5 UUIDs as specified in :rfc:`4122`.
+
+If all you want is a unique ID, you should probably call :func:`uuid1` or
+:func:`uuid4`. Note that :func:`uuid1` may compromise privacy since it creates
+a UUID containing the computer's network address. :func:`uuid4` creates a
+random UUID.
+
+
+.. class:: UUID([hex[, bytes[, bytes_le[, fields[, int[, version]]]]]])
+
+ Create a UUID from either a string of 32 hexadecimal digits, a string of 16
+ bytes as the *bytes* argument, a string of 16 bytes in little-endian order as
+ the *bytes_le* argument, a tuple of six integers (32-bit *time_low*, 16-bit
+ *time_mid*, 16-bit *time_hi_version*, 8-bit *clock_seq_hi_variant*, 8-bit
+ *clock_seq_low*, 48-bit *node*) as the *fields* argument, or a single 128-bit
+ integer as the *int* argument. When a string of hex digits is given, curly
+ braces, hyphens, and a URN prefix are all optional. For example, these
+ expressions all yield the same UUID::
+
+ UUID('{12345678-1234-5678-1234-567812345678}')
+ UUID('12345678123456781234567812345678')
+ UUID('urn:uuid:12345678-1234-5678-1234-567812345678')
+ UUID(bytes='\x12\x34\x56\x78'*4)
+ UUID(bytes_le='\x78\x56\x34\x12\x34\x12\x78\x56' +
+ '\x12\x34\x56\x78\x12\x34\x56\x78')
+ UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678))
+ UUID(int=0x12345678123456781234567812345678)
+
+ Exactly one of *hex*, *bytes*, *bytes_le*, *fields*, or *int* must be given.
+ The *version* argument is optional; if given, the resulting UUID will have its
+ variant and version number set according to RFC 4122, overriding bits in the
+ given *hex*, *bytes*, *bytes_le*, *fields*, or *int*.
+
+:class:`UUID` instances have these read-only attributes:
+
+
+.. attribute:: UUID.bytes
+
+ The UUID as a 16-byte string (containing the six integer fields in big-endian
+ byte order).
+
+
+.. attribute:: UUID.bytes_le
+
+ The UUID as a 16-byte string (with *time_low*, *time_mid*, and *time_hi_version*
+ in little-endian byte order).
+
+
+.. attribute:: UUID.fields
+
+ A tuple of the six integer fields of the UUID, which are also available as six
+ individual attributes and two derived attributes:
+
+ +------------------------------+-------------------------------+
+ | Field | Meaning |
+ +==============================+===============================+
+ | :attr:`time_low` | the first 32 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`time_mid` | the next 16 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`time_hi_version` | the next 16 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`clock_seq_hi_variant` | the next 8 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`clock_seq_low` | the next 8 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`node` | the last 48 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`time` | the 60-bit timestamp |
+ +------------------------------+-------------------------------+
+ | :attr:`clock_seq` | the 14-bit sequence number |
+ +------------------------------+-------------------------------+
+
+
+.. attribute:: UUID.hex
+
+ The UUID as a 32-character hexadecimal string.
+
+
+.. attribute:: UUID.int
+
+ The UUID as a 128-bit integer.
+
+
+.. attribute:: UUID.urn
+
+ The UUID as a URN as specified in RFC 4122.
+
+
+.. attribute:: UUID.variant
+
+ The UUID variant, which determines the internal layout of the UUID. This will be
+ one of the integer constants :const:`RESERVED_NCS`, :const:`RFC_4122`,
+ :const:`RESERVED_MICROSOFT`, or :const:`RESERVED_FUTURE`.
+
+
+.. attribute:: UUID.version
+
+ The UUID version number (1 through 5, meaningful only when the variant is
+ :const:`RFC_4122`).
+
+The :mod:`uuid` module defines the following functions:
+
+
+.. function:: getnode()
+
+ Get the hardware address as a 48-bit positive integer. The first time this
+ runs, it may launch a separate program, which could be quite slow. If all
+ attempts to obtain the hardware address fail, we choose a random 48-bit number
+ with its eighth bit set to 1 as recommended in RFC 4122. "Hardware address"
+ means the MAC address of a network interface, and on a machine with multiple
+ network interfaces the MAC address of any one of them may be returned.
+
+.. index:: single: getnode
+
+
+.. function:: uuid1([node[, clock_seq]])
+
+ Generate a UUID from a host ID, sequence number, and the current time. If *node*
+ is not given, :func:`getnode` is used to obtain the hardware address. If
+ *clock_seq* is given, it is used as the sequence number; otherwise a random
+ 14-bit sequence number is chosen.
+
+.. index:: single: uuid1
+
+
+.. function:: uuid3(namespace, name)
+
+ Generate a UUID based on the MD5 hash of a namespace identifier (which is a
+ UUID) and a name (which is a string).
+
+.. index:: single: uuid3
+
+
+.. function:: uuid4()
+
+ Generate a random UUID.
+
+.. index:: single: uuid4
+
+
+.. function:: uuid5(namespace, name)
+
+ Generate a UUID based on the SHA-1 hash of a namespace identifier (which is a
+ UUID) and a name (which is a string).
+
+.. index:: single: uuid5
+
+The :mod:`uuid` module defines the following namespace identifiers for use with
+:func:`uuid3` or :func:`uuid5`.
+
+
+.. data:: NAMESPACE_DNS
+
+ When this namespace is specified, the *name* string is a fully-qualified domain
+ name.
+
+
+.. data:: NAMESPACE_URL
+
+ When this namespace is specified, the *name* string is a URL.
+
+
+.. data:: NAMESPACE_OID
+
+ When this namespace is specified, the *name* string is an ISO OID.
+
+
+.. data:: NAMESPACE_X500
+
+ When this namespace is specified, the *name* string is an X.500 DN in DER or a
+ text output format.
+
+The :mod:`uuid` module defines the following constants for the possible values
+of the :attr:`variant` attribute:
+
+
+.. data:: RESERVED_NCS
+
+ Reserved for NCS compatibility.
+
+
+.. data:: RFC_4122
+
+ Specifies the UUID layout given in :rfc:`4122`.
+
+
+.. data:: RESERVED_MICROSOFT
+
+ Reserved for Microsoft compatibility.
+
+
+.. data:: RESERVED_FUTURE
+
+ Reserved for future definition.
+
+
+.. seealso::
+
+ :rfc:`4122` - A Universally Unique IDentifier (UUID) URN Namespace
+ This specification defines a Uniform Resource Name namespace for UUIDs, the
+ internal format of UUIDs, and methods of generating UUIDs.
+
+
+.. _uuid-example:
+
+Example
+-------
+
+Here are some examples of typical usage of the :mod:`uuid` module::
+
+ >>> import uuid
+
+ # make a UUID based on the host ID and current time
+ >>> uuid.uuid1()
+ UUID('a8098c1a-f86e-11da-bd1a-00112444be1e')
+
+ # make a UUID using an MD5 hash of a namespace UUID and a name
+ >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org')
+ UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e')
+
+ # make a random UUID
+ >>> uuid.uuid4()
+ UUID('16fd2706-8baf-433b-82eb-8c7fada847da')
+
+ # make a UUID using a SHA-1 hash of a namespace UUID and a name
+ >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org')
+ UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d')
+
+ # make a UUID from a string of hex digits (braces and hyphens ignored)
+ >>> x = uuid.UUID('{00010203-0405-0607-0809-0a0b0c0d0e0f}')
+
+ # convert a UUID to a string of hex digits in standard form
+ >>> str(x)
+ '00010203-0405-0607-0809-0a0b0c0d0e0f'
+
+ # get the raw 16 bytes of the UUID
+ >>> x.bytes
+ '\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f'
+
+ # make a UUID from a 16-byte string
+ >>> uuid.UUID(bytes=x.bytes)
+ UUID('00010203-0405-0607-0809-0a0b0c0d0e0f')
+
diff --git a/Doc/library/warnings.rst b/Doc/library/warnings.rst
new file mode 100644
index 0000000000..35e9888a03
--- /dev/null
+++ b/Doc/library/warnings.rst
@@ -0,0 +1,242 @@
+
+:mod:`warnings` --- Warning control
+===================================
+
+.. index:: single: warnings
+
+.. module:: warnings
+ :synopsis: Issue warning messages and control their disposition.
+
+
+.. versionadded:: 2.1
+
+Warning messages are typically issued in situations where it is useful to alert
+the user of some condition in a program, where that condition (normally) doesn't
+warrant raising an exception and terminating the program. For example, one
+might want to issue a warning when a program uses an obsolete module.
+
+Python programmers issue warnings by calling the :func:`warn` function defined
+in this module. (C programmers use :cfunc:`PyErr_WarnEx`; see
+:ref:`exceptionhandling` for details).
+
+Warning messages are normally written to ``sys.stderr``, but their disposition
+can be changed flexibly, from ignoring all warnings to turning them into
+exceptions. The disposition of warnings can vary based on the warning category
+(see below), the text of the warning message, and the source location where it
+is issued. Repetitions of a particular warning for the same source location are
+typically suppressed.
+
+There are two stages in warning control: first, each time a warning is issued, a
+determination is made whether a message should be issued or not; next, if a
+message is to be issued, it is formatted and printed using a user-settable hook.
+
+The determination whether to issue a warning message is controlled by the
+warning filter, which is a sequence of matching rules and actions. Rules can be
+added to the filter by calling :func:`filterwarnings` and reset to its default
+state by calling :func:`resetwarnings`.
+
+The printing of warning messages is done by calling :func:`showwarning`, which
+may be overridden; the default implementation of this function formats the
+message by calling :func:`formatwarning`, which is also available for use by
+custom implementations.
+
+
+.. _warning-categories:
+
+Warning Categories
+------------------
+
+There are a number of built-in exceptions that represent warning categories.
+This categorization is useful to be able to filter out groups of warnings. The
+following warnings category classes are currently defined:
+
++----------------------------------+-----------------------------------------------+
+| Class | Description |
++==================================+===============================================+
+| :exc:`Warning` | This is the base class of all warning |
+| | category classes. It is a subclass of |
+| | :exc:`Exception`. |
++----------------------------------+-----------------------------------------------+
+| :exc:`UserWarning` | The default category for :func:`warn`. |
++----------------------------------+-----------------------------------------------+
+| :exc:`DeprecationWarning` | Base category for warnings about deprecated |
+| | features. |
++----------------------------------+-----------------------------------------------+
+| :exc:`SyntaxWarning` | Base category for warnings about dubious |
+| | syntactic features. |
++----------------------------------+-----------------------------------------------+
+| :exc:`RuntimeWarning` | Base category for warnings about dubious |
+| | runtime features. |
++----------------------------------+-----------------------------------------------+
+| :exc:`FutureWarning` | Base category for warnings about constructs |
+| | that will change semantically in the future. |
++----------------------------------+-----------------------------------------------+
+| :exc:`PendingDeprecationWarning` | Base category for warnings about features |
+| | that will be deprecated in the future |
+| | (ignored by default). |
++----------------------------------+-----------------------------------------------+
+| :exc:`ImportWarning` | Base category for warnings triggered during |
+| | the process of importing a module (ignored by |
+| | default). |
++----------------------------------+-----------------------------------------------+
+| :exc:`UnicodeWarning` | Base category for warnings related to |
+| | Unicode. |
++----------------------------------+-----------------------------------------------+
+
+While these are technically built-in exceptions, they are documented here,
+because conceptually they belong to the warnings mechanism.
+
+User code can define additional warning categories by subclassing one of the
+standard warning categories. A warning category must always be a subclass of
+the :exc:`Warning` class.
+
+
+.. _warning-filter:
+
+The Warnings Filter
+-------------------
+
+The warnings filter controls whether warnings are ignored, displayed, or turned
+into errors (raising an exception).
+
+Conceptually, the warnings filter maintains an ordered list of filter
+specifications; any specific warning is matched against each filter
+specification in the list in turn until a match is found; the match determines
+the disposition of the match. Each entry is a tuple of the form (*action*,
+*message*, *category*, *module*, *lineno*), where:
+
+* *action* is one of the following strings:
+
+ +---------------+----------------------------------------------+
+ | Value | Disposition |
+ +===============+==============================================+
+ | ``"error"`` | turn matching warnings into exceptions |
+ +---------------+----------------------------------------------+
+ | ``"ignore"`` | never print matching warnings |
+ +---------------+----------------------------------------------+
+ | ``"always"`` | always print matching warnings |
+ +---------------+----------------------------------------------+
+ | ``"default"`` | print the first occurrence of matching |
+ | | warnings for each location where the warning |
+ | | is issued |
+ +---------------+----------------------------------------------+
+ | ``"module"`` | print the first occurrence of matching |
+ | | warnings for each module where the warning |
+ | | is issued |
+ +---------------+----------------------------------------------+
+ | ``"once"`` | print only the first occurrence of matching |
+ | | warnings, regardless of location |
+ +---------------+----------------------------------------------+
+
+* *message* is a string containing a regular expression that the warning message
+ must match (the match is compiled to always be case-insensitive)
+
+* *category* is a class (a subclass of :exc:`Warning`) of which the warning
+ category must be a subclass in order to match
+
+* *module* is a string containing a regular expression that the module name must
+ match (the match is compiled to be case-sensitive)
+
+* *lineno* is an integer that the line number where the warning occurred must
+ match, or ``0`` to match all line numbers
+
+Since the :exc:`Warning` class is derived from the built-in :exc:`Exception`
+class, to turn a warning into an error we simply raise ``category(message)``.
+
+The warnings filter is initialized by :option:`-W` options passed to the Python
+interpreter command line. The interpreter saves the arguments for all
+:option:`-W` options without interpretation in ``sys.warnoptions``; the
+:mod:`warnings` module parses these when it is first imported (invalid options
+are ignored, after printing a message to ``sys.stderr``).
+
+The warnings that are ignored by default may be enabled by passing :option:`-Wd`
+to the interpreter. This enables default handling for all warnings, including
+those that are normally ignored by default. This is particular useful for
+enabling ImportWarning when debugging problems importing a developed package.
+ImportWarning can also be enabled explicitly in Python code using::
+
+ warnings.simplefilter('default', ImportWarning)
+
+
+.. _warning-functions:
+
+Available Functions
+-------------------
+
+
+.. function:: warn(message[, category[, stacklevel]])
+
+ Issue a warning, or maybe ignore it or raise an exception. The *category*
+ argument, if given, must be a warning category class (see above); it defaults to
+ :exc:`UserWarning`. Alternatively *message* can be a :exc:`Warning` instance,
+ in which case *category* will be ignored and ``message.__class__`` will be used.
+ In this case the message text will be ``str(message)``. This function raises an
+ exception if the particular warning issued is changed into an error by the
+ warnings filter see above. The *stacklevel* argument can be used by wrapper
+ functions written in Python, like this::
+
+ def deprecation(message):
+ warnings.warn(message, DeprecationWarning, stacklevel=2)
+
+ This makes the warning refer to :func:`deprecation`'s caller, rather than to the
+ source of :func:`deprecation` itself (since the latter would defeat the purpose
+ of the warning message).
+
+
+.. function:: warn_explicit(message, category, filename, lineno[, module[, registry[, module_globals]]])
+
+ This is a low-level interface to the functionality of :func:`warn`, passing in
+ explicitly the message, category, filename and line number, and optionally the
+ module name and the registry (which should be the ``__warningregistry__``
+ dictionary of the module). The module name defaults to the filename with
+ ``.py`` stripped; if no registry is passed, the warning is never suppressed.
+ *message* must be a string and *category* a subclass of :exc:`Warning` or
+ *message* may be a :exc:`Warning` instance, in which case *category* will be
+ ignored.
+
+ *module_globals*, if supplied, should be the global namespace in use by the code
+ for which the warning is issued. (This argument is used to support displaying
+ source for modules found in zipfiles or other non-filesystem import sources, and
+ was added in Python 2.5.)
+
+
+.. function:: showwarning(message, category, filename, lineno[, file])
+
+ Write a warning to a file. The default implementation calls
+ ``formatwarning(message, category, filename, lineno)`` and writes the resulting
+ string to *file*, which defaults to ``sys.stderr``. You may replace this
+ function with an alternative implementation by assigning to
+ ``warnings.showwarning``.
+
+
+.. function:: formatwarning(message, category, filename, lineno)
+
+ Format a warning the standard way. This returns a string which may contain
+ embedded newlines and ends in a newline.
+
+
+.. function:: filterwarnings(action[, message[, category[, module[, lineno[, append]]]]])
+
+ Insert an entry into the list of warnings filters. The entry is inserted at the
+ front by default; if *append* is true, it is inserted at the end. This checks
+ the types of the arguments, compiles the message and module regular expressions,
+ and inserts them as a tuple in the list of warnings filters. Entries closer to
+ the front of the list override entries later in the list, if both match a
+ particular warning. Omitted arguments default to a value that matches
+ everything.
+
+
+.. function:: simplefilter(action[, category[, lineno[, append]]])
+
+ Insert a simple entry into the list of warnings filters. The meaning of the
+ function parameters is as for :func:`filterwarnings`, but regular expressions
+ are not needed as the filter inserted always matches any message in any module
+ as long as the category and line number match.
+
+
+.. function:: resetwarnings()
+
+ Reset the warnings filter. This discards the effect of all previous calls to
+ :func:`filterwarnings`, including that of the :option:`-W` command line options
+ and calls to :func:`simplefilter`.
+
diff --git a/Doc/library/wave.rst b/Doc/library/wave.rst
new file mode 100644
index 0000000000..d03f091826
--- /dev/null
+++ b/Doc/library/wave.rst
@@ -0,0 +1,201 @@
+.. % Documentations stolen and LaTeX'ed from comments in file.
+
+
+:mod:`wave` --- Read and write WAV files
+========================================
+
+.. module:: wave
+ :synopsis: Provide an interface to the WAV sound format.
+.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
+
+
+The :mod:`wave` module provides a convenient interface to the WAV sound format.
+It does not support compression/decompression, but it does support mono/stereo.
+
+The :mod:`wave` module defines the following function and exception:
+
+
+.. function:: open(file[, mode])
+
+ If *file* is a string, open the file by that name, other treat it as a seekable
+ file-like object. *mode* can be any of
+
+ ``'r'``, ``'rb'``
+ Read only mode.
+
+ ``'w'``, ``'wb'``
+ Write only mode.
+
+ Note that it does not allow read/write WAV files.
+
+ A *mode* of ``'r'`` or ``'rb'`` returns a :class:`Wave_read` object, while a
+ *mode* of ``'w'`` or ``'wb'`` returns a :class:`Wave_write` object. If *mode*
+ is omitted and a file-like object is passed as *file*, ``file.mode`` is used as
+ the default value for *mode* (the ``'b'`` flag is still added if necessary).
+
+
+.. function:: openfp(file, mode)
+
+ A synonym for :func:`open`, maintained for backwards compatibility.
+
+
+.. exception:: Error
+
+ An error raised when something is impossible because it violates the WAV
+ specification or hits an implementation deficiency.
+
+
+.. _wave-read-objects:
+
+Wave_read Objects
+-----------------
+
+Wave_read objects, as returned by :func:`open`, have the following methods:
+
+
+.. method:: Wave_read.close()
+
+ Close the stream, and make the instance unusable. This is called automatically
+ on object collection.
+
+
+.. method:: Wave_read.getnchannels()
+
+ Returns number of audio channels (``1`` for mono, ``2`` for stereo).
+
+
+.. method:: Wave_read.getsampwidth()
+
+ Returns sample width in bytes.
+
+
+.. method:: Wave_read.getframerate()
+
+ Returns sampling frequency.
+
+
+.. method:: Wave_read.getnframes()
+
+ Returns number of audio frames.
+
+
+.. method:: Wave_read.getcomptype()
+
+ Returns compression type (``'NONE'`` is the only supported type).
+
+
+.. method:: Wave_read.getcompname()
+
+ Human-readable version of :meth:`getcomptype`. Usually ``'not compressed'``
+ parallels ``'NONE'``.
+
+
+.. method:: Wave_read.getparams()
+
+ Returns a tuple ``(nchannels, sampwidth, framerate, nframes, comptype,
+ compname)``, equivalent to output of the :meth:`get\*` methods.
+
+
+.. method:: Wave_read.readframes(n)
+
+ Reads and returns at most *n* frames of audio, as a string of bytes.
+
+
+.. method:: Wave_read.rewind()
+
+ Rewind the file pointer to the beginning of the audio stream.
+
+The following two methods are defined for compatibility with the :mod:`aifc`
+module, and don't do anything interesting.
+
+
+.. method:: Wave_read.getmarkers()
+
+ Returns ``None``.
+
+
+.. method:: Wave_read.getmark(id)
+
+ Raise an error.
+
+The following two methods define a term "position" which is compatible between
+them, and is otherwise implementation dependent.
+
+
+.. method:: Wave_read.setpos(pos)
+
+ Set the file pointer to the specified position.
+
+
+.. method:: Wave_read.tell()
+
+ Return current file pointer position.
+
+
+.. _wave-write-objects:
+
+Wave_write Objects
+------------------
+
+Wave_write objects, as returned by :func:`open`, have the following methods:
+
+
+.. method:: Wave_write.close()
+
+ Make sure *nframes* is correct, and close the file. This method is called upon
+ deletion.
+
+
+.. method:: Wave_write.setnchannels(n)
+
+ Set the number of channels.
+
+
+.. method:: Wave_write.setsampwidth(n)
+
+ Set the sample width to *n* bytes.
+
+
+.. method:: Wave_write.setframerate(n)
+
+ Set the frame rate to *n*.
+
+
+.. method:: Wave_write.setnframes(n)
+
+ Set the number of frames to *n*. This will be changed later if more frames are
+ written.
+
+
+.. method:: Wave_write.setcomptype(type, name)
+
+ Set the compression type and description. At the moment, only compression type
+ ``NONE`` is supported, meaning no compression.
+
+
+.. method:: Wave_write.setparams(tuple)
+
+ The *tuple* should be ``(nchannels, sampwidth, framerate, nframes, comptype,
+ compname)``, with values valid for the :meth:`set\*` methods. Sets all
+ parameters.
+
+
+.. method:: Wave_write.tell()
+
+ Return current position in the file, with the same disclaimer for the
+ :meth:`Wave_read.tell` and :meth:`Wave_read.setpos` methods.
+
+
+.. method:: Wave_write.writeframesraw(data)
+
+ Write audio frames, without correcting *nframes*.
+
+
+.. method:: Wave_write.writeframes(data)
+
+ Write audio frames and make sure *nframes* is correct.
+
+Note that it is invalid to set any parameters after calling :meth:`writeframes`
+or :meth:`writeframesraw`, and any attempt to do so will raise
+:exc:`wave.Error`.
+
diff --git a/Doc/library/weakref.rst b/Doc/library/weakref.rst
new file mode 100644
index 0000000000..c5857ba3c7
--- /dev/null
+++ b/Doc/library/weakref.rst
@@ -0,0 +1,330 @@
+
+:mod:`weakref` --- Weak references
+==================================
+
+.. module:: weakref
+ :synopsis: Support for weak references and weak dictionaries.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. moduleauthor:: Neil Schemenauer <nas@arctrix.com>
+.. moduleauthor:: Martin von Löwis <martin@loewis.home.cs.tu-berlin.de>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. versionadded:: 2.1
+
+The :mod:`weakref` module allows the Python programmer to create :dfn:`weak
+references` to objects.
+
+.. % When making changes to the examples in this file, be sure to update
+.. % Lib/test/test_weakref.py::libreftest too!
+
+In the following, the term :dfn:`referent` means the object which is referred to
+by a weak reference.
+
+A weak reference to an object is not enough to keep the object alive: when the
+only remaining references to a referent are weak references, garbage collection
+is free to destroy the referent and reuse its memory for something else. A
+primary use for weak references is to implement caches or mappings holding large
+objects, where it's desired that a large object not be kept alive solely because
+it appears in a cache or mapping. For example, if you have a number of large
+binary image objects, you may wish to associate a name with each. If you used a
+Python dictionary to map names to images, or images to names, the image objects
+would remain alive just because they appeared as values or keys in the
+dictionaries. The :class:`WeakKeyDictionary` and :class:`WeakValueDictionary`
+classes supplied by the :mod:`weakref` module are an alternative, using weak
+references to construct mappings that don't keep objects alive solely because
+they appear in the mapping objects. If, for example, an image object is a value
+in a :class:`WeakValueDictionary`, then when the last remaining references to
+that image object are the weak references held by weak mappings, garbage
+collection can reclaim the object, and its corresponding entries in weak
+mappings are simply deleted.
+
+:class:`WeakKeyDictionary` and :class:`WeakValueDictionary` use weak references
+in their implementation, setting up callback functions on the weak references
+that notify the weak dictionaries when a key or value has been reclaimed by
+garbage collection. Most programs should find that using one of these weak
+dictionary types is all they need -- it's not usually necessary to create your
+own weak references directly. The low-level machinery used by the weak
+dictionary implementations is exposed by the :mod:`weakref` module for the
+benefit of advanced uses.
+
+Not all objects can be weakly referenced; those objects which can include class
+instances, functions written in Python (but not in C), methods (both bound and
+unbound), sets, frozensets, file objects, generators, type objects, DBcursor
+objects from the :mod:`bsddb` module, sockets, arrays, deques, and regular
+expression pattern objects.
+
+.. versionchanged:: 2.4
+ Added support for files, sockets, arrays, and patterns.
+
+Several builtin types such as :class:`list` and :class:`dict` do not directly
+support weak references but can add support through subclassing::
+
+ class Dict(dict):
+ pass
+
+ obj = Dict(red=1, green=2, blue=3) # this object is weak referencable
+
+Extension types can easily be made to support weak references; see
+:ref:`weakref-support`.
+
+
+.. class:: ref(object[, callback])
+
+ Return a weak reference to *object*. The original object can be retrieved by
+ calling the reference object if the referent is still alive; if the referent is
+ no longer alive, calling the reference object will cause :const:`None` to be
+ returned. If *callback* is provided and not :const:`None`, and the returned
+ weakref object is still alive, the callback will be called when the object is
+ about to be finalized; the weak reference object will be passed as the only
+ parameter to the callback; the referent will no longer be available.
+
+ It is allowable for many weak references to be constructed for the same object.
+ Callbacks registered for each weak reference will be called from the most
+ recently registered callback to the oldest registered callback.
+
+ Exceptions raised by the callback will be noted on the standard error output,
+ but cannot be propagated; they are handled in exactly the same way as exceptions
+ raised from an object's :meth:`__del__` method.
+
+ Weak references are hashable if the *object* is hashable. They will maintain
+ their hash value even after the *object* was deleted. If :func:`hash` is called
+ the first time only after the *object* was deleted, the call will raise
+ :exc:`TypeError`.
+
+ Weak references support tests for equality, but not ordering. If the referents
+ are still alive, two references have the same equality relationship as their
+ referents (regardless of the *callback*). If either referent has been deleted,
+ the references are equal only if the reference objects are the same object.
+
+ .. versionchanged:: 2.4
+ This is now a subclassable type rather than a factory function; it derives from
+ :class:`object`.
+
+
+.. function:: proxy(object[, callback])
+
+ Return a proxy to *object* which uses a weak reference. This supports use of
+ the proxy in most contexts instead of requiring the explicit dereferencing used
+ with weak reference objects. The returned object will have a type of either
+ ``ProxyType`` or ``CallableProxyType``, depending on whether *object* is
+ callable. Proxy objects are not hashable regardless of the referent; this
+ avoids a number of problems related to their fundamentally mutable nature, and
+ prevent their use as dictionary keys. *callback* is the same as the parameter
+ of the same name to the :func:`ref` function.
+
+
+.. function:: getweakrefcount(object)
+
+ Return the number of weak references and proxies which refer to *object*.
+
+
+.. function:: getweakrefs(object)
+
+ Return a list of all weak reference and proxy objects which refer to *object*.
+
+
+.. class:: WeakKeyDictionary([dict])
+
+ Mapping class that references keys weakly. Entries in the dictionary will be
+ discarded when there is no longer a strong reference to the key. This can be
+ used to associate additional data with an object owned by other parts of an
+ application without adding attributes to those objects. This can be especially
+ useful with objects that override attribute accesses.
+
+ .. note::
+
+ Caution: Because a :class:`WeakKeyDictionary` is built on top of a Python
+ dictionary, it must not change size when iterating over it. This can be
+ difficult to ensure for a :class:`WeakKeyDictionary` because actions performed
+ by the program during iteration may cause items in the dictionary to vanish "by
+ magic" (as a side effect of garbage collection).
+
+:class:`WeakKeyDictionary` objects have the following additional methods. These
+expose the internal references directly. The references are not guaranteed to
+be "live" at the time they are used, so the result of calling the references
+needs to be checked before being used. This can be used to avoid creating
+references that will cause the garbage collector to keep the keys around longer
+than needed.
+
+
+.. method:: WeakKeyDictionary.iterkeyrefs()
+
+ Return an iterator that yields the weak references to the keys.
+
+ .. versionadded:: 2.5
+
+
+.. method:: WeakKeyDictionary.keyrefs()
+
+ Return a list of weak references to the keys.
+
+ .. versionadded:: 2.5
+
+
+.. class:: WeakValueDictionary([dict])
+
+ Mapping class that references values weakly. Entries in the dictionary will be
+ discarded when no strong reference to the value exists any more.
+
+ .. note::
+
+ Caution: Because a :class:`WeakValueDictionary` is built on top of a Python
+ dictionary, it must not change size when iterating over it. This can be
+ difficult to ensure for a :class:`WeakValueDictionary` because actions performed
+ by the program during iteration may cause items in the dictionary to vanish "by
+ magic" (as a side effect of garbage collection).
+
+:class:`WeakValueDictionary` objects have the following additional methods.
+These method have the same issues as the :meth:`iterkeyrefs` and :meth:`keyrefs`
+methods of :class:`WeakKeyDictionary` objects.
+
+
+.. method:: WeakValueDictionary.itervaluerefs()
+
+ Return an iterator that yields the weak references to the values.
+
+ .. versionadded:: 2.5
+
+
+.. method:: WeakValueDictionary.valuerefs()
+
+ Return a list of weak references to the values.
+
+ .. versionadded:: 2.5
+
+
+.. data:: ReferenceType
+
+ The type object for weak references objects.
+
+
+.. data:: ProxyType
+
+ The type object for proxies of objects which are not callable.
+
+
+.. data:: CallableProxyType
+
+ The type object for proxies of callable objects.
+
+
+.. data:: ProxyTypes
+
+ Sequence containing all the type objects for proxies. This can make it simpler
+ to test if an object is a proxy without being dependent on naming both proxy
+ types.
+
+
+.. exception:: ReferenceError
+
+ Exception raised when a proxy object is used but the underlying object has been
+ collected. This is the same as the standard :exc:`ReferenceError` exception.
+
+
+.. seealso::
+
+ :pep:`0205` - Weak References
+ The proposal and rationale for this feature, including links to earlier
+ implementations and information about similar features in other languages.
+
+
+.. _weakref-objects:
+
+Weak Reference Objects
+----------------------
+
+Weak reference objects have no attributes or methods, but do allow the referent
+to be obtained, if it still exists, by calling it::
+
+ >>> import weakref
+ >>> class Object:
+ ... pass
+ ...
+ >>> o = Object()
+ >>> r = weakref.ref(o)
+ >>> o2 = r()
+ >>> o is o2
+ True
+
+If the referent no longer exists, calling the reference object returns
+:const:`None`::
+
+ >>> del o, o2
+ >>> print r()
+ None
+
+Testing that a weak reference object is still live should be done using the
+expression ``ref() is not None``. Normally, application code that needs to use
+a reference object should follow this pattern::
+
+ # r is a weak reference object
+ o = r()
+ if o is None:
+ # referent has been garbage collected
+ print "Object has been deallocated; can't frobnicate."
+ else:
+ print "Object is still live!"
+ o.do_something_useful()
+
+Using a separate test for "liveness" creates race conditions in threaded
+applications; another thread can cause a weak reference to become invalidated
+before the weak reference is called; the idiom shown above is safe in threaded
+applications as well as single-threaded applications.
+
+Specialized versions of :class:`ref` objects can be created through subclassing.
+This is used in the implementation of the :class:`WeakValueDictionary` to reduce
+the memory overhead for each entry in the mapping. This may be most useful to
+associate additional information with a reference, but could also be used to
+insert additional processing on calls to retrieve the referent.
+
+This example shows how a subclass of :class:`ref` can be used to store
+additional information about an object and affect the value that's returned when
+the referent is accessed::
+
+ import weakref
+
+ class ExtendedRef(weakref.ref):
+ def __init__(self, ob, callback=None, **annotations):
+ super(ExtendedRef, self).__init__(ob, callback)
+ self.__counter = 0
+ for k, v in annotations.iteritems():
+ setattr(self, k, v)
+
+ def __call__(self):
+ """Return a pair containing the referent and the number of
+ times the reference has been called.
+ """
+ ob = super(ExtendedRef, self).__call__()
+ if ob is not None:
+ self.__counter += 1
+ ob = (ob, self.__counter)
+ return ob
+
+
+.. _weakref-example:
+
+Example
+-------
+
+This simple example shows how an application can use objects IDs to retrieve
+objects that it has seen before. The IDs of the objects can then be used in
+other data structures without forcing the objects to remain alive, but the
+objects can still be retrieved by ID if they do.
+
+.. % Example contributed by Tim Peters.
+
+::
+
+ import weakref
+
+ _id2obj_dict = weakref.WeakValueDictionary()
+
+ def remember(obj):
+ oid = id(obj)
+ _id2obj_dict[oid] = obj
+ return oid
+
+ def id2obj(oid):
+ return _id2obj_dict[oid]
+
diff --git a/Doc/library/webbrowser.rst b/Doc/library/webbrowser.rst
new file mode 100644
index 0000000000..c243f7c366
--- /dev/null
+++ b/Doc/library/webbrowser.rst
@@ -0,0 +1,199 @@
+
+:mod:`webbrowser` --- Convenient Web-browser controller
+=======================================================
+
+.. module:: webbrowser
+ :synopsis: Easy-to-use controller for Web browsers.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`webbrowser` module provides a high-level interface to allow displaying
+Web-based documents to users. Under most circumstances, simply calling the
+:func:`open` function from this module will do the right thing.
+
+Under Unix, graphical browsers are preferred under X11, but text-mode browsers
+will be used if graphical browsers are not available or an X11 display isn't
+available. If text-mode browsers are used, the calling process will block until
+the user exits the browser.
+
+If the environment variable :envvar:`BROWSER` exists, it is interpreted to
+override the platform default list of browsers, as a os.pathsep-separated list
+of browsers to try in order. When the value of a list part contains the string
+``%s``, then it is interpreted as a literal browser command line to be used
+with the argument URL substituted for ``%s``; if the part does not contain
+``%s``, it is simply interpreted as the name of the browser to launch.
+
+For non-Unix platforms, or when a remote browser is available on Unix, the
+controlling process will not wait for the user to finish with the browser, but
+allow the remote browser to maintain its own windows on the display. If remote
+browsers are not available on Unix, the controlling process will launch a new
+browser and wait.
+
+The script :program:`webbrowser` can be used as a command-line interface for the
+module. It accepts an URL as the argument. It accepts the following optional
+parameters: :option:`-n` opens the URL in a new browser window, if possible;
+:option:`-t` opens the URL in a new browser page ("tab"). The options are,
+naturally, mutually exclusive.
+
+The following exception is defined:
+
+
+.. exception:: Error
+
+ Exception raised when a browser control error occurs.
+
+The following functions are defined:
+
+
+.. function:: open(url[, new=0[, autoraise=1]])
+
+ Display *url* using the default browser. If *new* is 0, the *url* is opened in
+ the same browser window if possible. If *new* is 1, a new browser window is
+ opened if possible. If *new* is 2, a new browser page ("tab") is opened if
+ possible. If *autoraise* is true, the window is raised if possible (note that
+ under many window managers this will occur regardless of the setting of this
+ variable).
+
+ .. versionchanged:: 2.5
+ *new* can now be 2.
+
+
+.. function:: open_new(url)
+
+ Open *url* in a new window of the default browser, if possible, otherwise, open
+ *url* in the only browser window.
+
+
+.. function:: open_new_tab(url)
+
+ Open *url* in a new page ("tab") of the default browser, if possible, otherwise
+ equivalent to :func:`open_new`.
+
+ .. versionadded:: 2.5
+
+
+.. function:: get([name])
+
+ Return a controller object for the browser type *name*. If *name* is empty,
+ return a controller for a default browser appropriate to the caller's
+ environment.
+
+
+.. function:: register(name, constructor[, instance])
+
+ Register the browser type *name*. Once a browser type is registered, the
+ :func:`get` function can return a controller for that browser type. If
+ *instance* is not provided, or is ``None``, *constructor* will be called without
+ parameters to create an instance when needed. If *instance* is provided,
+ *constructor* will never be called, and may be ``None``.
+
+ This entry point is only useful if you plan to either set the :envvar:`BROWSER`
+ variable or call :func:`get` with a nonempty argument matching the name of a
+ handler you declare.
+
+A number of browser types are predefined. This table gives the type names that
+may be passed to the :func:`get` function and the corresponding instantiations
+for the controller classes, all defined in this module.
+
++-----------------------+-----------------------------------------+-------+
+| Type Name | Class Name | Notes |
++=======================+=========================================+=======+
+| ``'mozilla'`` | :class:`Mozilla('mozilla')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'firefox'`` | :class:`Mozilla('mozilla')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'netscape'`` | :class:`Mozilla('netscape')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'galeon'`` | :class:`Galeon('galeon')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'epiphany'`` | :class:`Galeon('epiphany')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'skipstone'`` | :class:`BackgroundBrowser('skipstone')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'kfmclient'`` | :class:`Konqueror()` | \(1) |
++-----------------------+-----------------------------------------+-------+
+| ``'konqueror'`` | :class:`Konqueror()` | \(1) |
++-----------------------+-----------------------------------------+-------+
+| ``'kfm'`` | :class:`Konqueror()` | \(1) |
++-----------------------+-----------------------------------------+-------+
+| ``'mosaic'`` | :class:`BackgroundBrowser('mosaic')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'opera'`` | :class:`Opera()` | |
++-----------------------+-----------------------------------------+-------+
+| ``'grail'`` | :class:`Grail()` | |
++-----------------------+-----------------------------------------+-------+
+| ``'links'`` | :class:`GenericBrowser('links')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'elinks'`` | :class:`Elinks('elinks')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'lynx'`` | :class:`GenericBrowser('lynx')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'w3m'`` | :class:`GenericBrowser('w3m')` | |
++-----------------------+-----------------------------------------+-------+
+| ``'windows-default'`` | :class:`WindowsDefault` | \(2) |
++-----------------------+-----------------------------------------+-------+
+| ``'internet-config'`` | :class:`InternetConfig` | \(3) |
++-----------------------+-----------------------------------------+-------+
+| ``'macosx'`` | :class:`MacOSX('default')` | \(4) |
++-----------------------+-----------------------------------------+-------+
+
+Notes:
+
+(1)
+ "Konqueror" is the file manager for the KDE desktop environment for Unix, and
+ only makes sense to use if KDE is running. Some way of reliably detecting KDE
+ would be nice; the :envvar:`KDEDIR` variable is not sufficient. Note also that
+ the name "kfm" is used even when using the :program:`konqueror` command with KDE
+ 2 --- the implementation selects the best strategy for running Konqueror.
+
+(2)
+ Only on Windows platforms.
+
+(3)
+ Only on MacOS platforms; requires the standard MacPython :mod:`ic` module.
+
+(4)
+ Only on MacOS X platform.
+
+Here are some simple examples::
+
+ url = 'http://www.python.org'
+
+ # Open URL in a new tab, if a browser window is already open.
+ webbrowser.open_new_tab(url + '/doc')
+
+ # Open URL in new window, raising the window if possible.
+ webbrowser.open_new(url)
+
+
+.. _browser-controllers:
+
+Browser Controller Objects
+--------------------------
+
+Browser controllers provide two methods which parallel two of the module-level
+convenience functions:
+
+
+.. method:: controller.open(url[, new[, autoraise=1]])
+
+ Display *url* using the browser handled by this controller. If *new* is 1, a new
+ browser window is opened if possible. If *new* is 2, a new browser page ("tab")
+ is opened if possible.
+
+
+.. method:: controller.open_new(url)
+
+ Open *url* in a new window of the browser handled by this controller, if
+ possible, otherwise, open *url* in the only browser window. Alias
+ :func:`open_new`.
+
+
+.. method:: controller.open_new_tab(url)
+
+ Open *url* in a new page ("tab") of the browser handled by this controller, if
+ possible, otherwise equivalent to :func:`open_new`.
+
+ .. versionadded:: 2.5
+
diff --git a/Doc/library/whichdb.rst b/Doc/library/whichdb.rst
new file mode 100644
index 0000000000..5c698183fc
--- /dev/null
+++ b/Doc/library/whichdb.rst
@@ -0,0 +1,20 @@
+
+:mod:`whichdb` --- Guess which DBM module created a database
+============================================================
+
+.. module:: whichdb
+ :synopsis: Guess which DBM-style module created a given database.
+
+
+The single function in this module attempts to guess which of the several simple
+database modules available--\ :mod:`dbm`, :mod:`gdbm`, or :mod:`dbhash`\
+--should be used to open a given file.
+
+
+.. function:: whichdb(filename)
+
+ Returns one of the following values: ``None`` if the file can't be opened
+ because it's unreadable or doesn't exist; the empty string (``''``) if the
+ file's format can't be guessed; or a string containing the required module name,
+ such as ``'dbm'`` or ``'gdbm'``.
+
diff --git a/Doc/library/windows.rst b/Doc/library/windows.rst
new file mode 100644
index 0000000000..a231bc2a4d
--- /dev/null
+++ b/Doc/library/windows.rst
@@ -0,0 +1,14 @@
+
+****************************
+MS Windows Specific Services
+****************************
+
+This chapter describes modules that are only available on MS Windows platforms.
+
+
+.. toctree::
+
+ msilib.rst
+ msvcrt.rst
+ _winreg.rst
+ winsound.rst
diff --git a/Doc/library/winsound.rst b/Doc/library/winsound.rst
new file mode 100644
index 0000000000..c4c04bd058
--- /dev/null
+++ b/Doc/library/winsound.rst
@@ -0,0 +1,162 @@
+
+:mod:`winsound` --- Sound-playing interface for Windows
+=======================================================
+
+.. module:: winsound
+ :platform: Windows
+ :synopsis: Access to the sound-playing machinery for Windows.
+.. moduleauthor:: Toby Dickenson <htrd90@zepler.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+.. versionadded:: 1.5.2
+
+The :mod:`winsound` module provides access to the basic sound-playing machinery
+provided by Windows platforms. It includes functions and several constants.
+
+
+.. function:: Beep(frequency, duration)
+
+ Beep the PC's speaker. The *frequency* parameter specifies frequency, in hertz,
+ of the sound, and must be in the range 37 through 32,767. The *duration*
+ parameter specifies the number of milliseconds the sound should last. If the
+ system is not able to beep the speaker, :exc:`RuntimeError` is raised.
+
+ .. note::
+
+ Under Windows 95 and 98, the Windows :cfunc:`Beep` function exists but is
+ useless (it ignores its arguments). In that case Python simulates it via direct
+ port manipulation (added in version 2.1). It's unknown whether that will work
+ on all systems.
+
+ .. versionadded:: 1.6
+
+
+.. function:: PlaySound(sound, flags)
+
+ Call the underlying :cfunc:`PlaySound` function from the Platform API. The
+ *sound* parameter may be a filename, audio data as a string, or ``None``. Its
+ interpretation depends on the value of *flags*, which can be a bit-wise ORed
+ combination of the constants described below. If the system indicates an error,
+ :exc:`RuntimeError` is raised.
+
+
+.. function:: MessageBeep([type=MB_OK])
+
+ Call the underlying :cfunc:`MessageBeep` function from the Platform API. This
+ plays a sound as specified in the registry. The *type* argument specifies which
+ sound to play; possible values are ``-1``, ``MB_ICONASTERISK``,
+ ``MB_ICONEXCLAMATION``, ``MB_ICONHAND``, ``MB_ICONQUESTION``, and ``MB_OK``, all
+ described below. The value ``-1`` produces a "simple beep"; this is the final
+ fallback if a sound cannot be played otherwise.
+
+ .. versionadded:: 2.3
+
+
+.. data:: SND_FILENAME
+
+ The *sound* parameter is the name of a WAV file. Do not use with
+ :const:`SND_ALIAS`.
+
+
+.. data:: SND_ALIAS
+
+ The *sound* parameter is a sound association name from the registry. If the
+ registry contains no such name, play the system default sound unless
+ :const:`SND_NODEFAULT` is also specified. If no default sound is registered,
+ raise :exc:`RuntimeError`. Do not use with :const:`SND_FILENAME`.
+
+ All Win32 systems support at least the following; most systems support many
+ more:
+
+ +--------------------------+----------------------------------------+
+ | :func:`PlaySound` *name* | Corresponding Control Panel Sound name |
+ +==========================+========================================+
+ | ``'SystemAsterisk'`` | Asterisk |
+ +--------------------------+----------------------------------------+
+ | ``'SystemExclamation'`` | Exclamation |
+ +--------------------------+----------------------------------------+
+ | ``'SystemExit'`` | Exit Windows |
+ +--------------------------+----------------------------------------+
+ | ``'SystemHand'`` | Critical Stop |
+ +--------------------------+----------------------------------------+
+ | ``'SystemQuestion'`` | Question |
+ +--------------------------+----------------------------------------+
+
+ For example::
+
+ import winsound
+ # Play Windows exit sound.
+ winsound.PlaySound("SystemExit", winsound.SND_ALIAS)
+
+ # Probably play Windows default sound, if any is registered (because
+ # "*" probably isn't the registered name of any sound).
+ winsound.PlaySound("*", winsound.SND_ALIAS)
+
+
+.. data:: SND_LOOP
+
+ Play the sound repeatedly. The :const:`SND_ASYNC` flag must also be used to
+ avoid blocking. Cannot be used with :const:`SND_MEMORY`.
+
+
+.. data:: SND_MEMORY
+
+ The *sound* parameter to :func:`PlaySound` is a memory image of a WAV file, as a
+ string.
+
+ .. note::
+
+ This module does not support playing from a memory image asynchronously, so a
+ combination of this flag and :const:`SND_ASYNC` will raise :exc:`RuntimeError`.
+
+
+.. data:: SND_PURGE
+
+ Stop playing all instances of the specified sound.
+
+
+.. data:: SND_ASYNC
+
+ Return immediately, allowing sounds to play asynchronously.
+
+
+.. data:: SND_NODEFAULT
+
+ If the specified sound cannot be found, do not play the system default sound.
+
+
+.. data:: SND_NOSTOP
+
+ Do not interrupt sounds currently playing.
+
+
+.. data:: SND_NOWAIT
+
+ Return immediately if the sound driver is busy.
+
+
+.. data:: MB_ICONASTERISK
+
+ Play the ``SystemDefault`` sound.
+
+
+.. data:: MB_ICONEXCLAMATION
+
+ Play the ``SystemExclamation`` sound.
+
+
+.. data:: MB_ICONHAND
+
+ Play the ``SystemHand`` sound.
+
+
+.. data:: MB_ICONQUESTION
+
+ Play the ``SystemQuestion`` sound.
+
+
+.. data:: MB_OK
+
+ Play the ``SystemDefault`` sound.
+
diff --git a/Doc/library/wsgiref.rst b/Doc/library/wsgiref.rst
new file mode 100644
index 0000000000..ff68684057
--- /dev/null
+++ b/Doc/library/wsgiref.rst
@@ -0,0 +1,641 @@
+:mod:`wsgiref` --- WSGI Utilities and Reference Implementation
+==============================================================
+
+.. module:: wsgiref
+ :synopsis: WSGI Utilities and Reference Implementation.
+.. moduleauthor:: Phillip J. Eby <pje@telecommunity.com>
+.. sectionauthor:: Phillip J. Eby <pje@telecommunity.com>
+
+
+.. versionadded:: 2.5
+
+The Web Server Gateway Interface (WSGI) is a standard interface between web
+server software and web applications written in Python. Having a standard
+interface makes it easy to use an application that supports WSGI with a number
+of different web servers.
+
+Only authors of web servers and programming frameworks need to know every detail
+and corner case of the WSGI design. You don't need to understand every detail
+of WSGI just to install a WSGI application or to write a web application using
+an existing framework.
+
+:mod:`wsgiref` is a reference implementation of the WSGI specification that can
+be used to add WSGI support to a web server or framework. It provides utilities
+for manipulating WSGI environment variables and response headers, base classes
+for implementing WSGI servers, a demo HTTP server that serves WSGI applications,
+and a validation tool that checks WSGI servers and applications for conformance
+to the WSGI specification (:pep:`333`).
+
+See http://www.wsgi.org for more information about WSGI, and links to tutorials
+and other resources.
+
+.. % XXX If you're just trying to write a web application...
+
+
+:mod:`wsgiref.util` -- WSGI environment utilities
+-------------------------------------------------
+
+.. module:: wsgiref.util
+ :synopsis: WSGI environment utilities.
+
+
+This module provides a variety of utility functions for working with WSGI
+environments. A WSGI environment is a dictionary containing HTTP request
+variables as described in :pep:`333`. All of the functions taking an *environ*
+parameter expect a WSGI-compliant dictionary to be supplied; please see
+:pep:`333` for a detailed specification.
+
+
+.. function:: guess_scheme(environ)
+
+ Return a guess for whether ``wsgi.url_scheme`` should be "http" or "https", by
+ checking for a ``HTTPS`` environment variable in the *environ* dictionary. The
+ return value is a string.
+
+ This function is useful when creating a gateway that wraps CGI or a CGI-like
+ protocol such as FastCGI. Typically, servers providing such protocols will
+ include a ``HTTPS`` variable with a value of "1" "yes", or "on" when a request
+ is received via SSL. So, this function returns "https" if such a value is
+ found, and "http" otherwise.
+
+
+.. function:: request_uri(environ [, include_query=1])
+
+ Return the full request URI, optionally including the query string, using the
+ algorithm found in the "URL Reconstruction" section of :pep:`333`. If
+ *include_query* is false, the query string is not included in the resulting URI.
+
+
+.. function:: application_uri(environ)
+
+ Similar to :func:`request_uri`, except that the ``PATH_INFO`` and
+ ``QUERY_STRING`` variables are ignored. The result is the base URI of the
+ application object addressed by the request.
+
+
+.. function:: shift_path_info(environ)
+
+ Shift a single name from ``PATH_INFO`` to ``SCRIPT_NAME`` and return the name.
+ The *environ* dictionary is *modified* in-place; use a copy if you need to keep
+ the original ``PATH_INFO`` or ``SCRIPT_NAME`` intact.
+
+ If there are no remaining path segments in ``PATH_INFO``, ``None`` is returned.
+
+ Typically, this routine is used to process each portion of a request URI path,
+ for example to treat the path as a series of dictionary keys. This routine
+ modifies the passed-in environment to make it suitable for invoking another WSGI
+ application that is located at the target URI. For example, if there is a WSGI
+ application at ``/foo``, and the request URI path is ``/foo/bar/baz``, and the
+ WSGI application at ``/foo`` calls :func:`shift_path_info`, it will receive the
+ string "bar", and the environment will be updated to be suitable for passing to
+ a WSGI application at ``/foo/bar``. That is, ``SCRIPT_NAME`` will change from
+ ``/foo`` to ``/foo/bar``, and ``PATH_INFO`` will change from ``/bar/baz`` to
+ ``/baz``.
+
+ When ``PATH_INFO`` is just a "/", this routine returns an empty string and
+ appends a trailing slash to ``SCRIPT_NAME``, even though empty path segments are
+ normally ignored, and ``SCRIPT_NAME`` doesn't normally end in a slash. This is
+ intentional behavior, to ensure that an application can tell the difference
+ between URIs ending in ``/x`` from ones ending in ``/x/`` when using this
+ routine to do object traversal.
+
+
+.. function:: setup_testing_defaults(environ)
+
+ Update *environ* with trivial defaults for testing purposes.
+
+ This routine adds various parameters required for WSGI, including ``HTTP_HOST``,
+ ``SERVER_NAME``, ``SERVER_PORT``, ``REQUEST_METHOD``, ``SCRIPT_NAME``,
+ ``PATH_INFO``, and all of the :pep:`333`\ -defined ``wsgi.*`` variables. It
+ only supplies default values, and does not replace any existing settings for
+ these variables.
+
+ This routine is intended to make it easier for unit tests of WSGI servers and
+ applications to set up dummy environments. It should NOT be used by actual WSGI
+ servers or applications, since the data is fake!
+
+In addition to the environment functions above, the :mod:`wsgiref.util` module
+also provides these miscellaneous utilities:
+
+
+.. function:: is_hop_by_hop(header_name)
+
+ Return true if 'header_name' is an HTTP/1.1 "Hop-by-Hop" header, as defined by
+ :rfc:`2616`.
+
+
+.. class:: FileWrapper(filelike [, blksize=8192])
+
+ A wrapper to convert a file-like object to an iterator. The resulting objects
+ support both :meth:`__getitem__` and :meth:`__iter__` iteration styles, for
+ compatibility with Python 2.1 and Jython. As the object is iterated over, the
+ optional *blksize* parameter will be repeatedly passed to the *filelike*
+ object's :meth:`read` method to obtain strings to yield. When :meth:`read`
+ returns an empty string, iteration is ended and is not resumable.
+
+ If *filelike* has a :meth:`close` method, the returned object will also have a
+ :meth:`close` method, and it will invoke the *filelike* object's :meth:`close`
+ method when called.
+
+
+:mod:`wsgiref.headers` -- WSGI response header tools
+----------------------------------------------------
+
+.. module:: wsgiref.headers
+ :synopsis: WSGI response header tools.
+
+
+This module provides a single class, :class:`Headers`, for convenient
+manipulation of WSGI response headers using a mapping-like interface.
+
+
+.. class:: Headers(headers)
+
+ Create a mapping-like object wrapping *headers*, which must be a list of header
+ name/value tuples as described in :pep:`333`. Any changes made to the new
+ :class:`Headers` object will directly update the *headers* list it was created
+ with.
+
+ :class:`Headers` objects support typical mapping operations including
+ :meth:`__getitem__`, :meth:`get`, :meth:`__setitem__`, :meth:`setdefault`,
+ :meth:`__delitem__`, :meth:`__contains__` and :meth:`has_key`. For each of
+ these methods, the key is the header name (treated case-insensitively), and the
+ value is the first value associated with that header name. Setting a header
+ deletes any existing values for that header, then adds a new value at the end of
+ the wrapped header list. Headers' existing order is generally maintained, with
+ new headers added to the end of the wrapped list.
+
+ Unlike a dictionary, :class:`Headers` objects do not raise an error when you try
+ to get or delete a key that isn't in the wrapped header list. Getting a
+ nonexistent header just returns ``None``, and deleting a nonexistent header does
+ nothing.
+
+ :class:`Headers` objects also support :meth:`keys`, :meth:`values`, and
+ :meth:`items` methods. The lists returned by :meth:`keys` and :meth:`items` can
+ include the same key more than once if there is a multi-valued header. The
+ ``len()`` of a :class:`Headers` object is the same as the length of its
+ :meth:`items`, which is the same as the length of the wrapped header list. In
+ fact, the :meth:`items` method just returns a copy of the wrapped header list.
+
+ Calling ``str()`` on a :class:`Headers` object returns a formatted string
+ suitable for transmission as HTTP response headers. Each header is placed on a
+ line with its value, separated by a colon and a space. Each line is terminated
+ by a carriage return and line feed, and the string is terminated with a blank
+ line.
+
+ In addition to their mapping interface and formatting features, :class:`Headers`
+ objects also have the following methods for querying and adding multi-valued
+ headers, and for adding headers with MIME parameters:
+
+
+ .. method:: Headers.get_all(name)
+
+ Return a list of all the values for the named header.
+
+ The returned list will be sorted in the order they appeared in the original
+ header list or were added to this instance, and may contain duplicates. Any
+ fields deleted and re-inserted are always appended to the header list. If no
+ fields exist with the given name, returns an empty list.
+
+
+ .. method:: Headers.add_header(name, value, **_params)
+
+ Add a (possibly multi-valued) header, with optional MIME parameters specified
+ via keyword arguments.
+
+ *name* is the header field to add. Keyword arguments can be used to set MIME
+ parameters for the header field. Each parameter must be a string or ``None``.
+ Underscores in parameter names are converted to dashes, since dashes are illegal
+ in Python identifiers, but many MIME parameter names include dashes. If the
+ parameter value is a string, it is added to the header value parameters in the
+ form ``name="value"``. If it is ``None``, only the parameter name is added.
+ (This is used for MIME parameters without a value.) Example usage::
+
+ h.add_header('content-disposition', 'attachment', filename='bud.gif')
+
+ The above will add a header that looks like this::
+
+ Content-Disposition: attachment; filename="bud.gif"
+
+
+:mod:`wsgiref.simple_server` -- a simple WSGI HTTP server
+---------------------------------------------------------
+
+.. module:: wsgiref.simple_server
+ :synopsis: A simple WSGI HTTP server.
+
+
+This module implements a simple HTTP server (based on :mod:`BaseHTTPServer`)
+that serves WSGI applications. Each server instance serves a single WSGI
+application on a given host and port. If you want to serve multiple
+applications on a single host and port, you should create a WSGI application
+that parses ``PATH_INFO`` to select which application to invoke for each
+request. (E.g., using the :func:`shift_path_info` function from
+:mod:`wsgiref.util`.)
+
+
+.. function:: make_server(host, port, app [, server_class=WSGIServer [, handler_class=WSGIRequestHandler]])
+
+ Create a new WSGI server listening on *host* and *port*, accepting connections
+ for *app*. The return value is an instance of the supplied *server_class*, and
+ will process requests using the specified *handler_class*. *app* must be a WSGI
+ application object, as defined by :pep:`333`.
+
+ Example usage::
+
+ from wsgiref.simple_server import make_server, demo_app
+
+ httpd = make_server('', 8000, demo_app)
+ print "Serving HTTP on port 8000..."
+
+ # Respond to requests until process is killed
+ httpd.serve_forever()
+
+ # Alternative: serve one request, then exit
+ ##httpd.handle_request()
+
+
+.. function:: demo_app(environ, start_response)
+
+ This function is a small but complete WSGI application that returns a text page
+ containing the message "Hello world!" and a list of the key/value pairs provided
+ in the *environ* parameter. It's useful for verifying that a WSGI server (such
+ as :mod:`wsgiref.simple_server`) is able to run a simple WSGI application
+ correctly.
+
+
+.. class:: WSGIServer(server_address, RequestHandlerClass)
+
+ Create a :class:`WSGIServer` instance. *server_address* should be a
+ ``(host,port)`` tuple, and *RequestHandlerClass* should be the subclass of
+ :class:`BaseHTTPServer.BaseHTTPRequestHandler` that will be used to process
+ requests.
+
+ You do not normally need to call this constructor, as the :func:`make_server`
+ function can handle all the details for you.
+
+ :class:`WSGIServer` is a subclass of :class:`BaseHTTPServer.HTTPServer`, so all
+ of its methods (such as :meth:`serve_forever` and :meth:`handle_request`) are
+ available. :class:`WSGIServer` also provides these WSGI-specific methods:
+
+
+ .. method:: WSGIServer.set_app(application)
+
+ Sets the callable *application* as the WSGI application that will receive
+ requests.
+
+
+ .. method:: WSGIServer.get_app()
+
+ Returns the currently-set application callable.
+
+ Normally, however, you do not need to use these additional methods, as
+ :meth:`set_app` is normally called by :func:`make_server`, and the
+ :meth:`get_app` exists mainly for the benefit of request handler instances.
+
+
+.. class:: WSGIRequestHandler(request, client_address, server)
+
+ Create an HTTP handler for the given *request* (i.e. a socket), *client_address*
+ (a ``(host,port)`` tuple), and *server* (:class:`WSGIServer` instance).
+
+ You do not need to create instances of this class directly; they are
+ automatically created as needed by :class:`WSGIServer` objects. You can,
+ however, subclass this class and supply it as a *handler_class* to the
+ :func:`make_server` function. Some possibly relevant methods for overriding in
+ subclasses:
+
+
+ .. method:: WSGIRequestHandler.get_environ()
+
+ Returns a dictionary containing the WSGI environment for a request. The default
+ implementation copies the contents of the :class:`WSGIServer` object's
+ :attr:`base_environ` dictionary attribute and then adds various headers derived
+ from the HTTP request. Each call to this method should return a new dictionary
+ containing all of the relevant CGI environment variables as specified in
+ :pep:`333`.
+
+
+ .. method:: WSGIRequestHandler.get_stderr()
+
+ Return the object that should be used as the ``wsgi.errors`` stream. The default
+ implementation just returns ``sys.stderr``.
+
+
+ .. method:: WSGIRequestHandler.handle()
+
+ Process the HTTP request. The default implementation creates a handler instance
+ using a :mod:`wsgiref.handlers` class to implement the actual WSGI application
+ interface.
+
+
+:mod:`wsgiref.validate` --- WSGI conformance checker
+----------------------------------------------------
+
+.. module:: wsgiref.validate
+ :synopsis: WSGI conformance checker.
+
+
+When creating new WSGI application objects, frameworks, servers, or middleware,
+it can be useful to validate the new code's conformance using
+:mod:`wsgiref.validate`. This module provides a function that creates WSGI
+application objects that validate communications between a WSGI server or
+gateway and a WSGI application object, to check both sides for protocol
+conformance.
+
+Note that this utility does not guarantee complete :pep:`333` compliance; an
+absence of errors from this module does not necessarily mean that errors do not
+exist. However, if this module does produce an error, then it is virtually
+certain that either the server or application is not 100% compliant.
+
+This module is based on the :mod:`paste.lint` module from Ian Bicking's "Python
+Paste" library.
+
+
+.. function:: validator(application)
+
+ Wrap *application* and return a new WSGI application object. The returned
+ application will forward all requests to the original *application*, and will
+ check that both the *application* and the server invoking it are conforming to
+ the WSGI specification and to RFC 2616.
+
+ Any detected nonconformance results in an :exc:`AssertionError` being raised;
+ note, however, that how these errors are handled is server-dependent. For
+ example, :mod:`wsgiref.simple_server` and other servers based on
+ :mod:`wsgiref.handlers` (that don't override the error handling methods to do
+ something else) will simply output a message that an error has occurred, and
+ dump the traceback to ``sys.stderr`` or some other error stream.
+
+ This wrapper may also generate output using the :mod:`warnings` module to
+ indicate behaviors that are questionable but which may not actually be
+ prohibited by :pep:`333`. Unless they are suppressed using Python command-line
+ options or the :mod:`warnings` API, any such warnings will be written to
+ ``sys.stderr`` (*not* ``wsgi.errors``, unless they happen to be the same
+ object).
+
+
+:mod:`wsgiref.handlers` -- server/gateway base classes
+------------------------------------------------------
+
+.. module:: wsgiref.handlers
+ :synopsis: WSGI server/gateway base classes.
+
+
+This module provides base handler classes for implementing WSGI servers and
+gateways. These base classes handle most of the work of communicating with a
+WSGI application, as long as they are given a CGI-like environment, along with
+input, output, and error streams.
+
+
+.. class:: CGIHandler()
+
+ CGI-based invocation via ``sys.stdin``, ``sys.stdout``, ``sys.stderr`` and
+ ``os.environ``. This is useful when you have a WSGI application and want to run
+ it as a CGI script. Simply invoke ``CGIHandler().run(app)``, where ``app`` is
+ the WSGI application object you wish to invoke.
+
+ This class is a subclass of :class:`BaseCGIHandler` that sets ``wsgi.run_once``
+ to true, ``wsgi.multithread`` to false, and ``wsgi.multiprocess`` to true, and
+ always uses :mod:`sys` and :mod:`os` to obtain the necessary CGI streams and
+ environment.
+
+
+.. class:: BaseCGIHandler(stdin, stdout, stderr, environ [, multithread=True [, multiprocess=False]])
+
+ Similar to :class:`CGIHandler`, but instead of using the :mod:`sys` and
+ :mod:`os` modules, the CGI environment and I/O streams are specified explicitly.
+ The *multithread* and *multiprocess* values are used to set the
+ ``wsgi.multithread`` and ``wsgi.multiprocess`` flags for any applications run by
+ the handler instance.
+
+ This class is a subclass of :class:`SimpleHandler` intended for use with
+ software other than HTTP "origin servers". If you are writing a gateway
+ protocol implementation (such as CGI, FastCGI, SCGI, etc.) that uses a
+ ``Status:`` header to send an HTTP status, you probably want to subclass this
+ instead of :class:`SimpleHandler`.
+
+
+.. class:: SimpleHandler(stdin, stdout, stderr, environ [,multithread=True [, multiprocess=False]])
+
+ Similar to :class:`BaseCGIHandler`, but designed for use with HTTP origin
+ servers. If you are writing an HTTP server implementation, you will probably
+ want to subclass this instead of :class:`BaseCGIHandler`
+
+ This class is a subclass of :class:`BaseHandler`. It overrides the
+ :meth:`__init__`, :meth:`get_stdin`, :meth:`get_stderr`, :meth:`add_cgi_vars`,
+ :meth:`_write`, and :meth:`_flush` methods to support explicitly setting the
+ environment and streams via the constructor. The supplied environment and
+ streams are stored in the :attr:`stdin`, :attr:`stdout`, :attr:`stderr`, and
+ :attr:`environ` attributes.
+
+
+.. class:: BaseHandler()
+
+ This is an abstract base class for running WSGI applications. Each instance
+ will handle a single HTTP request, although in principle you could create a
+ subclass that was reusable for multiple requests.
+
+ :class:`BaseHandler` instances have only one method intended for external use:
+
+
+ .. method:: BaseHandler.run(app)
+
+ Run the specified WSGI application, *app*.
+
+ All of the other :class:`BaseHandler` methods are invoked by this method in the
+ process of running the application, and thus exist primarily to allow
+ customizing the process.
+
+ The following methods MUST be overridden in a subclass:
+
+
+ .. method:: BaseHandler._write(data)
+
+ Buffer the string *data* for transmission to the client. It's okay if this
+ method actually transmits the data; :class:`BaseHandler` just separates write
+ and flush operations for greater efficiency when the underlying system actually
+ has such a distinction.
+
+
+ .. method:: BaseHandler._flush()
+
+ Force buffered data to be transmitted to the client. It's okay if this method
+ is a no-op (i.e., if :meth:`_write` actually sends the data).
+
+
+ .. method:: BaseHandler.get_stdin()
+
+ Return an input stream object suitable for use as the ``wsgi.input`` of the
+ request currently being processed.
+
+
+ .. method:: BaseHandler.get_stderr()
+
+ Return an output stream object suitable for use as the ``wsgi.errors`` of the
+ request currently being processed.
+
+
+ .. method:: BaseHandler.add_cgi_vars()
+
+ Insert CGI variables for the current request into the :attr:`environ` attribute.
+
+ Here are some other methods and attributes you may wish to override. This list
+ is only a summary, however, and does not include every method that can be
+ overridden. You should consult the docstrings and source code for additional
+ information before attempting to create a customized :class:`BaseHandler`
+ subclass.
+
+ Attributes and methods for customizing the WSGI environment:
+
+
+ .. attribute:: BaseHandler.wsgi_multithread
+
+ The value to be used for the ``wsgi.multithread`` environment variable. It
+ defaults to true in :class:`BaseHandler`, but may have a different default (or
+ be set by the constructor) in the other subclasses.
+
+
+ .. attribute:: BaseHandler.wsgi_multiprocess
+
+ The value to be used for the ``wsgi.multiprocess`` environment variable. It
+ defaults to true in :class:`BaseHandler`, but may have a different default (or
+ be set by the constructor) in the other subclasses.
+
+
+ .. attribute:: BaseHandler.wsgi_run_once
+
+ The value to be used for the ``wsgi.run_once`` environment variable. It
+ defaults to false in :class:`BaseHandler`, but :class:`CGIHandler` sets it to
+ true by default.
+
+
+ .. attribute:: BaseHandler.os_environ
+
+ The default environment variables to be included in every request's WSGI
+ environment. By default, this is a copy of ``os.environ`` at the time that
+ :mod:`wsgiref.handlers` was imported, but subclasses can either create their own
+ at the class or instance level. Note that the dictionary should be considered
+ read-only, since the default value is shared between multiple classes and
+ instances.
+
+
+ .. attribute:: BaseHandler.server_software
+
+ If the :attr:`origin_server` attribute is set, this attribute's value is used to
+ set the default ``SERVER_SOFTWARE`` WSGI environment variable, and also to set a
+ default ``Server:`` header in HTTP responses. It is ignored for handlers (such
+ as :class:`BaseCGIHandler` and :class:`CGIHandler`) that are not HTTP origin
+ servers.
+
+
+ .. method:: BaseHandler.get_scheme()
+
+ Return the URL scheme being used for the current request. The default
+ implementation uses the :func:`guess_scheme` function from :mod:`wsgiref.util`
+ to guess whether the scheme should be "http" or "https", based on the current
+ request's :attr:`environ` variables.
+
+
+ .. method:: BaseHandler.setup_environ()
+
+ Set the :attr:`environ` attribute to a fully-populated WSGI environment. The
+ default implementation uses all of the above methods and attributes, plus the
+ :meth:`get_stdin`, :meth:`get_stderr`, and :meth:`add_cgi_vars` methods and the
+ :attr:`wsgi_file_wrapper` attribute. It also inserts a ``SERVER_SOFTWARE`` key
+ if not present, as long as the :attr:`origin_server` attribute is a true value
+ and the :attr:`server_software` attribute is set.
+
+ Methods and attributes for customizing exception handling:
+
+
+ .. method:: BaseHandler.log_exception(exc_info)
+
+ Log the *exc_info* tuple in the server log. *exc_info* is a ``(type, value,
+ traceback)`` tuple. The default implementation simply writes the traceback to
+ the request's ``wsgi.errors`` stream and flushes it. Subclasses can override
+ this method to change the format or retarget the output, mail the traceback to
+ an administrator, or whatever other action may be deemed suitable.
+
+
+ .. attribute:: BaseHandler.traceback_limit
+
+ The maximum number of frames to include in tracebacks output by the default
+ :meth:`log_exception` method. If ``None``, all frames are included.
+
+
+ .. method:: BaseHandler.error_output(environ, start_response)
+
+ This method is a WSGI application to generate an error page for the user. It is
+ only invoked if an error occurs before headers are sent to the client.
+
+ This method can access the current error information using ``sys.exc_info()``,
+ and should pass that information to *start_response* when calling it (as
+ described in the "Error Handling" section of :pep:`333`).
+
+ The default implementation just uses the :attr:`error_status`,
+ :attr:`error_headers`, and :attr:`error_body` attributes to generate an output
+ page. Subclasses can override this to produce more dynamic error output.
+
+ Note, however, that it's not recommended from a security perspective to spit out
+ diagnostics to any old user; ideally, you should have to do something special to
+ enable diagnostic output, which is why the default implementation doesn't
+ include any.
+
+
+ .. attribute:: BaseHandler.error_status
+
+ The HTTP status used for error responses. This should be a status string as
+ defined in :pep:`333`; it defaults to a 500 code and message.
+
+
+ .. attribute:: BaseHandler.error_headers
+
+ The HTTP headers used for error responses. This should be a list of WSGI
+ response headers (``(name, value)`` tuples), as described in :pep:`333`. The
+ default list just sets the content type to ``text/plain``.
+
+
+ .. attribute:: BaseHandler.error_body
+
+ The error response body. This should be an HTTP response body string. It
+ defaults to the plain text, "A server error occurred. Please contact the
+ administrator."
+
+ Methods and attributes for :pep:`333`'s "Optional Platform-Specific File
+ Handling" feature:
+
+
+ .. attribute:: BaseHandler.wsgi_file_wrapper
+
+ A ``wsgi.file_wrapper`` factory, or ``None``. The default value of this
+ attribute is the :class:`FileWrapper` class from :mod:`wsgiref.util`.
+
+
+ .. method:: BaseHandler.sendfile()
+
+ Override to implement platform-specific file transmission. This method is
+ called only if the application's return value is an instance of the class
+ specified by the :attr:`wsgi_file_wrapper` attribute. It should return a true
+ value if it was able to successfully transmit the file, so that the default
+ transmission code will not be executed. The default implementation of this
+ method just returns a false value.
+
+ Miscellaneous methods and attributes:
+
+
+ .. attribute:: BaseHandler.origin_server
+
+ This attribute should be set to a true value if the handler's :meth:`_write` and
+ :meth:`_flush` are being used to communicate directly to the client, rather than
+ via a CGI-like gateway protocol that wants the HTTP status in a special
+ ``Status:`` header.
+
+ This attribute's default value is true in :class:`BaseHandler`, but false in
+ :class:`BaseCGIHandler` and :class:`CGIHandler`.
+
+
+ .. attribute:: BaseHandler.http_version
+
+ If :attr:`origin_server` is true, this string attribute is used to set the HTTP
+ version of the response set to the client. It defaults to ``"1.0"``.
+
diff --git a/Doc/library/xdrlib.rst b/Doc/library/xdrlib.rst
new file mode 100644
index 0000000000..6339a7fcea
--- /dev/null
+++ b/Doc/library/xdrlib.rst
@@ -0,0 +1,276 @@
+
+:mod:`xdrlib` --- Encode and decode XDR data
+============================================
+
+.. module:: xdrlib
+ :synopsis: Encoders and decoders for the External Data Representation (XDR).
+
+
+.. index::
+ single: XDR
+ single: External Data Representation
+
+The :mod:`xdrlib` module supports the External Data Representation Standard as
+described in :rfc:`1014`, written by Sun Microsystems, Inc. June 1987. It
+supports most of the data types described in the RFC.
+
+The :mod:`xdrlib` module defines two classes, one for packing variables into XDR
+representation, and another for unpacking from XDR representation. There are
+also two exception classes.
+
+
+.. class:: Packer()
+
+ :class:`Packer` is the class for packing data into XDR representation. The
+ :class:`Packer` class is instantiated with no arguments.
+
+
+.. class:: Unpacker(data)
+
+ ``Unpacker`` is the complementary class which unpacks XDR data values from a
+ string buffer. The input buffer is given as *data*.
+
+
+.. seealso::
+
+ :rfc:`1014` - XDR: External Data Representation Standard
+ This RFC defined the encoding of data which was XDR at the time this module was
+ originally written. It has apparently been obsoleted by :rfc:`1832`.
+
+ :rfc:`1832` - XDR: External Data Representation Standard
+ Newer RFC that provides a revised definition of XDR.
+
+
+.. _xdr-packer-objects:
+
+Packer Objects
+--------------
+
+:class:`Packer` instances have the following methods:
+
+
+.. method:: Packer.get_buffer()
+
+ Returns the current pack buffer as a string.
+
+
+.. method:: Packer.reset()
+
+ Resets the pack buffer to the empty string.
+
+In general, you can pack any of the most common XDR data types by calling the
+appropriate ``pack_type()`` method. Each method takes a single argument, the
+value to pack. The following simple data type packing methods are supported:
+:meth:`pack_uint`, :meth:`pack_int`, :meth:`pack_enum`, :meth:`pack_bool`,
+:meth:`pack_uhyper`, and :meth:`pack_hyper`.
+
+
+.. method:: Packer.pack_float(value)
+
+ Packs the single-precision floating point number *value*.
+
+
+.. method:: Packer.pack_double(value)
+
+ Packs the double-precision floating point number *value*.
+
+The following methods support packing strings, bytes, and opaque data:
+
+
+.. method:: Packer.pack_fstring(n, s)
+
+ Packs a fixed length string, *s*. *n* is the length of the string but it is
+ *not* packed into the data buffer. The string is padded with null bytes if
+ necessary to guaranteed 4 byte alignment.
+
+
+.. method:: Packer.pack_fopaque(n, data)
+
+ Packs a fixed length opaque data stream, similarly to :meth:`pack_fstring`.
+
+
+.. method:: Packer.pack_string(s)
+
+ Packs a variable length string, *s*. The length of the string is first packed
+ as an unsigned integer, then the string data is packed with
+ :meth:`pack_fstring`.
+
+
+.. method:: Packer.pack_opaque(data)
+
+ Packs a variable length opaque data string, similarly to :meth:`pack_string`.
+
+
+.. method:: Packer.pack_bytes(bytes)
+
+ Packs a variable length byte stream, similarly to :meth:`pack_string`.
+
+The following methods support packing arrays and lists:
+
+
+.. method:: Packer.pack_list(list, pack_item)
+
+ Packs a *list* of homogeneous items. This method is useful for lists with an
+ indeterminate size; i.e. the size is not available until the entire list has
+ been walked. For each item in the list, an unsigned integer ``1`` is packed
+ first, followed by the data value from the list. *pack_item* is the function
+ that is called to pack the individual item. At the end of the list, an unsigned
+ integer ``0`` is packed.
+
+ For example, to pack a list of integers, the code might appear like this::
+
+ import xdrlib
+ p = xdrlib.Packer()
+ p.pack_list([1, 2, 3], p.pack_int)
+
+
+.. method:: Packer.pack_farray(n, array, pack_item)
+
+ Packs a fixed length list (*array*) of homogeneous items. *n* is the length of
+ the list; it is *not* packed into the buffer, but a :exc:`ValueError` exception
+ is raised if ``len(array)`` is not equal to *n*. As above, *pack_item* is the
+ function used to pack each element.
+
+
+.. method:: Packer.pack_array(list, pack_item)
+
+ Packs a variable length *list* of homogeneous items. First, the length of the
+ list is packed as an unsigned integer, then each element is packed as in
+ :meth:`pack_farray` above.
+
+
+.. _xdr-unpacker-objects:
+
+Unpacker Objects
+----------------
+
+The :class:`Unpacker` class offers the following methods:
+
+
+.. method:: Unpacker.reset(data)
+
+ Resets the string buffer with the given *data*.
+
+
+.. method:: Unpacker.get_position()
+
+ Returns the current unpack position in the data buffer.
+
+
+.. method:: Unpacker.set_position(position)
+
+ Sets the data buffer unpack position to *position*. You should be careful about
+ using :meth:`get_position` and :meth:`set_position`.
+
+
+.. method:: Unpacker.get_buffer()
+
+ Returns the current unpack data buffer as a string.
+
+
+.. method:: Unpacker.done()
+
+ Indicates unpack completion. Raises an :exc:`Error` exception if all of the
+ data has not been unpacked.
+
+In addition, every data type that can be packed with a :class:`Packer`, can be
+unpacked with an :class:`Unpacker`. Unpacking methods are of the form
+``unpack_type()``, and take no arguments. They return the unpacked object.
+
+
+.. method:: Unpacker.unpack_float()
+
+ Unpacks a single-precision floating point number.
+
+
+.. method:: Unpacker.unpack_double()
+
+ Unpacks a double-precision floating point number, similarly to
+ :meth:`unpack_float`.
+
+In addition, the following methods unpack strings, bytes, and opaque data:
+
+
+.. method:: Unpacker.unpack_fstring(n)
+
+ Unpacks and returns a fixed length string. *n* is the number of characters
+ expected. Padding with null bytes to guaranteed 4 byte alignment is assumed.
+
+
+.. method:: Unpacker.unpack_fopaque(n)
+
+ Unpacks and returns a fixed length opaque data stream, similarly to
+ :meth:`unpack_fstring`.
+
+
+.. method:: Unpacker.unpack_string()
+
+ Unpacks and returns a variable length string. The length of the string is first
+ unpacked as an unsigned integer, then the string data is unpacked with
+ :meth:`unpack_fstring`.
+
+
+.. method:: Unpacker.unpack_opaque()
+
+ Unpacks and returns a variable length opaque data string, similarly to
+ :meth:`unpack_string`.
+
+
+.. method:: Unpacker.unpack_bytes()
+
+ Unpacks and returns a variable length byte stream, similarly to
+ :meth:`unpack_string`.
+
+The following methods support unpacking arrays and lists:
+
+
+.. method:: Unpacker.unpack_list(unpack_item)
+
+ Unpacks and returns a list of homogeneous items. The list is unpacked one
+ element at a time by first unpacking an unsigned integer flag. If the flag is
+ ``1``, then the item is unpacked and appended to the list. A flag of ``0``
+ indicates the end of the list. *unpack_item* is the function that is called to
+ unpack the items.
+
+
+.. method:: Unpacker.unpack_farray(n, unpack_item)
+
+ Unpacks and returns (as a list) a fixed length array of homogeneous items. *n*
+ is number of list elements to expect in the buffer. As above, *unpack_item* is
+ the function used to unpack each element.
+
+
+.. method:: Unpacker.unpack_array(unpack_item)
+
+ Unpacks and returns a variable length *list* of homogeneous items. First, the
+ length of the list is unpacked as an unsigned integer, then each element is
+ unpacked as in :meth:`unpack_farray` above.
+
+
+.. _xdr-exceptions:
+
+Exceptions
+----------
+
+Exceptions in this module are coded as class instances:
+
+
+.. exception:: Error
+
+ The base exception class. :exc:`Error` has a single public data member
+ :attr:`msg` containing the description of the error.
+
+
+.. exception:: ConversionError
+
+ Class derived from :exc:`Error`. Contains no additional instance variables.
+
+Here is an example of how you would catch one of these exceptions::
+
+ import xdrlib
+ p = xdrlib.Packer()
+ try:
+ p.pack_double(8.01)
+ except xdrlib.ConversionError as instance:
+ print 'packing the double failed:', instance.msg
+
diff --git a/Doc/library/xml.dom.minidom.rst b/Doc/library/xml.dom.minidom.rst
new file mode 100644
index 0000000000..54c5f3d825
--- /dev/null
+++ b/Doc/library/xml.dom.minidom.rst
@@ -0,0 +1,267 @@
+
+:mod:`xml.dom.minidom` --- Lightweight DOM implementation
+=========================================================
+
+.. module:: xml.dom.minidom
+ :synopsis: Lightweight Document Object Model (DOM) implementation.
+.. moduleauthor:: Paul Prescod <paul@prescod.net>
+.. sectionauthor:: Paul Prescod <paul@prescod.net>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.0
+
+:mod:`xml.dom.minidom` is a light-weight implementation of the Document Object
+Model interface. It is intended to be simpler than the full DOM and also
+significantly smaller.
+
+DOM applications typically start by parsing some XML into a DOM. With
+:mod:`xml.dom.minidom`, this is done through the parse functions::
+
+ from xml.dom.minidom import parse, parseString
+
+ dom1 = parse('c:\\temp\\mydata.xml') # parse an XML file by name
+
+ datasource = open('c:\\temp\\mydata.xml')
+ dom2 = parse(datasource) # parse an open file
+
+ dom3 = parseString('<myxml>Some data<empty/> some more data</myxml>')
+
+The :func:`parse` function can take either a filename or an open file object.
+
+
+.. function:: parse(filename_or_file, parser)
+
+ Return a :class:`Document` from the given input. *filename_or_file* may be
+ either a file name, or a file-like object. *parser*, if given, must be a SAX2
+ parser object. This function will change the document handler of the parser and
+ activate namespace support; other parser configuration (like setting an entity
+ resolver) must have been done in advance.
+
+If you have XML in a string, you can use the :func:`parseString` function
+instead:
+
+
+.. function:: parseString(string[, parser])
+
+ Return a :class:`Document` that represents the *string*. This method creates a
+ :class:`StringIO` object for the string and passes that on to :func:`parse`.
+
+Both functions return a :class:`Document` object representing the content of the
+document.
+
+What the :func:`parse` and :func:`parseString` functions do is connect an XML
+parser with a "DOM builder" that can accept parse events from any SAX parser and
+convert them into a DOM tree. The name of the functions are perhaps misleading,
+but are easy to grasp when learning the interfaces. The parsing of the document
+will be completed before these functions return; it's simply that these
+functions do not provide a parser implementation themselves.
+
+You can also create a :class:`Document` by calling a method on a "DOM
+Implementation" object. You can get this object either by calling the
+:func:`getDOMImplementation` function in the :mod:`xml.dom` package or the
+:mod:`xml.dom.minidom` module. Using the implementation from the
+:mod:`xml.dom.minidom` module will always return a :class:`Document` instance
+from the minidom implementation, while the version from :mod:`xml.dom` may
+provide an alternate implementation (this is likely if you have the `PyXML
+package <http://pyxml.sourceforge.net/>`_ installed). Once you have a
+:class:`Document`, you can add child nodes to it to populate the DOM::
+
+ from xml.dom.minidom import getDOMImplementation
+
+ impl = getDOMImplementation()
+
+ newdoc = impl.createDocument(None, "some_tag", None)
+ top_element = newdoc.documentElement
+ text = newdoc.createTextNode('Some textual content.')
+ top_element.appendChild(text)
+
+Once you have a DOM document object, you can access the parts of your XML
+document through its properties and methods. These properties are defined in
+the DOM specification. The main property of the document object is the
+:attr:`documentElement` property. It gives you the main element in the XML
+document: the one that holds all others. Here is an example program::
+
+ dom3 = parseString("<myxml>Some data</myxml>")
+ assert dom3.documentElement.tagName == "myxml"
+
+When you are finished with a DOM, you should clean it up. This is necessary
+because some versions of Python do not support garbage collection of objects
+that refer to each other in a cycle. Until this restriction is removed from all
+versions of Python, it is safest to write your code as if cycles would not be
+cleaned up.
+
+The way to clean up a DOM is to call its :meth:`unlink` method::
+
+ dom1.unlink()
+ dom2.unlink()
+ dom3.unlink()
+
+:meth:`unlink` is a :mod:`xml.dom.minidom`\ -specific extension to the DOM API.
+After calling :meth:`unlink` on a node, the node and its descendants are
+essentially useless.
+
+
+.. seealso::
+
+ `Document Object Model (DOM) Level 1 Specification <http://www.w3.org/TR/REC-DOM-Level-1/>`_
+ The W3C recommendation for the DOM supported by :mod:`xml.dom.minidom`.
+
+
+.. _minidom-objects:
+
+DOM Objects
+-----------
+
+The definition of the DOM API for Python is given as part of the :mod:`xml.dom`
+module documentation. This section lists the differences between the API and
+:mod:`xml.dom.minidom`.
+
+
+.. method:: Node.unlink()
+
+ Break internal references within the DOM so that it will be garbage collected on
+ versions of Python without cyclic GC. Even when cyclic GC is available, using
+ this can make large amounts of memory available sooner, so calling this on DOM
+ objects as soon as they are no longer needed is good practice. This only needs
+ to be called on the :class:`Document` object, but may be called on child nodes
+ to discard children of that node.
+
+
+.. method:: Node.writexml(writer[,indent=""[,addindent=""[,newl=""]]])
+
+ Write XML to the writer object. The writer should have a :meth:`write` method
+ which matches that of the file object interface. The *indent* parameter is the
+ indentation of the current node. The *addindent* parameter is the incremental
+ indentation to use for subnodes of the current one. The *newl* parameter
+ specifies the string to use to terminate newlines.
+
+ .. versionchanged:: 2.1
+ The optional keyword parameters *indent*, *addindent*, and *newl* were added to
+ support pretty output.
+
+ .. versionchanged:: 2.3
+ For the :class:`Document` node, an additional keyword argument *encoding* can be
+ used to specify the encoding field of the XML header.
+
+
+.. method:: Node.toxml([encoding])
+
+ Return the XML that the DOM represents as a string.
+
+ With no argument, the XML header does not specify an encoding, and the result is
+ Unicode string if the default encoding cannot represent all characters in the
+ document. Encoding this string in an encoding other than UTF-8 is likely
+ incorrect, since UTF-8 is the default encoding of XML.
+
+ With an explicit *encoding* argument, the result is a byte string in the
+ specified encoding. It is recommended that this argument is always specified. To
+ avoid :exc:`UnicodeError` exceptions in case of unrepresentable text data, the
+ encoding argument should be specified as "utf-8".
+
+ .. versionchanged:: 2.3
+ the *encoding* argument was introduced.
+
+
+.. method:: Node.toprettyxml([indent[, newl]])
+
+ Return a pretty-printed version of the document. *indent* specifies the
+ indentation string and defaults to a tabulator; *newl* specifies the string
+ emitted at the end of each line and defaults to ``\n``.
+
+ .. versionadded:: 2.1
+
+ .. versionchanged:: 2.3
+ the encoding argument; see :meth:`toxml`.
+
+The following standard DOM methods have special considerations with
+:mod:`xml.dom.minidom`:
+
+
+.. method:: Node.cloneNode(deep)
+
+ Although this method was present in the version of :mod:`xml.dom.minidom`
+ packaged with Python 2.0, it was seriously broken. This has been corrected for
+ subsequent releases.
+
+
+.. _dom-example:
+
+DOM Example
+-----------
+
+This example program is a fairly realistic example of a simple program. In this
+particular case, we do not take much advantage of the flexibility of the DOM.
+
+.. literalinclude:: ../includes/minidom-example.py
+
+
+.. _minidom-and-dom:
+
+minidom and the DOM standard
+----------------------------
+
+The :mod:`xml.dom.minidom` module is essentially a DOM 1.0-compatible DOM with
+some DOM 2 features (primarily namespace features).
+
+Usage of the DOM interface in Python is straight-forward. The following mapping
+rules apply:
+
+* Interfaces are accessed through instance objects. Applications should not
+ instantiate the classes themselves; they should use the creator functions
+ available on the :class:`Document` object. Derived interfaces support all
+ operations (and attributes) from the base interfaces, plus any new operations.
+
+* Operations are used as methods. Since the DOM uses only :keyword:`in`
+ parameters, the arguments are passed in normal order (from left to right).
+ There are no optional arguments. :keyword:`void` operations return ``None``.
+
+* IDL attributes map to instance attributes. For compatibility with the OMG IDL
+ language mapping for Python, an attribute ``foo`` can also be accessed through
+ accessor methods :meth:`_get_foo` and :meth:`_set_foo`. :keyword:`readonly`
+ attributes must not be changed; this is not enforced at runtime.
+
+* The types ``short int``, ``unsigned int``, ``unsigned long long``, and
+ ``boolean`` all map to Python integer objects.
+
+* The type ``DOMString`` maps to Python strings. :mod:`xml.dom.minidom` supports
+ either byte or Unicode strings, but will normally produce Unicode strings.
+ Values of type ``DOMString`` may also be ``None`` where allowed to have the IDL
+ ``null`` value by the DOM specification from the W3C.
+
+* :keyword:`const` declarations map to variables in their respective scope (e.g.
+ ``xml.dom.minidom.Node.PROCESSING_INSTRUCTION_NODE``); they must not be changed.
+
+* ``DOMException`` is currently not supported in :mod:`xml.dom.minidom`.
+ Instead, :mod:`xml.dom.minidom` uses standard Python exceptions such as
+ :exc:`TypeError` and :exc:`AttributeError`.
+
+* :class:`NodeList` objects are implemented using Python's built-in list type.
+ Starting with Python 2.2, these objects provide the interface defined in the DOM
+ specification, but with earlier versions of Python they do not support the
+ official API. They are, however, much more "Pythonic" than the interface
+ defined in the W3C recommendations.
+
+The following interfaces have no implementation in :mod:`xml.dom.minidom`:
+
+* :class:`DOMTimeStamp`
+
+* :class:`DocumentType` (added in Python 2.1)
+
+* :class:`DOMImplementation` (added in Python 2.1)
+
+* :class:`CharacterData`
+
+* :class:`CDATASection`
+
+* :class:`Notation`
+
+* :class:`Entity`
+
+* :class:`EntityReference`
+
+* :class:`DocumentFragment`
+
+Most of these reflect information in the XML document that is not of general
+utility to most DOM users.
+
diff --git a/Doc/library/xml.dom.pulldom.rst b/Doc/library/xml.dom.pulldom.rst
new file mode 100644
index 0000000000..80a91b8ec7
--- /dev/null
+++ b/Doc/library/xml.dom.pulldom.rst
@@ -0,0 +1,69 @@
+
+:mod:`xml.dom.pulldom` --- Support for building partial DOM trees
+=================================================================
+
+.. module:: xml.dom.pulldom
+ :synopsis: Support for building partial DOM trees from SAX events.
+.. moduleauthor:: Paul Prescod <paul@prescod.net>
+
+
+.. versionadded:: 2.0
+
+:mod:`xml.dom.pulldom` allows building only selected portions of a Document
+Object Model representation of a document from SAX events.
+
+
+.. class:: PullDOM([documentFactory])
+
+ :class:`xml.sax.handler.ContentHandler` implementation that ...
+
+
+.. class:: DOMEventStream(stream, parser, bufsize)
+
+ ...
+
+
+.. class:: SAX2DOM([documentFactory])
+
+ :class:`xml.sax.handler.ContentHandler` implementation that ...
+
+
+.. function:: parse(stream_or_string[, parser[, bufsize]])
+
+ ...
+
+
+.. function:: parseString(string[, parser])
+
+ ...
+
+
+.. data:: default_bufsize
+
+ Default value for the *bufsize* parameter to :func:`parse`.
+
+ .. versionchanged:: 2.1
+ The value of this variable can be changed before calling :func:`parse` and the
+ new value will take effect.
+
+
+.. _domeventstream-objects:
+
+DOMEventStream Objects
+----------------------
+
+
+.. method:: DOMEventStream.getEvent()
+
+ ...
+
+
+.. method:: DOMEventStream.expandNode(node)
+
+ ...
+
+
+.. method:: DOMEventStream.reset()
+
+ ...
+
diff --git a/Doc/library/xml.dom.rst b/Doc/library/xml.dom.rst
new file mode 100644
index 0000000000..76f5cc1a8c
--- /dev/null
+++ b/Doc/library/xml.dom.rst
@@ -0,0 +1,1045 @@
+
+:mod:`xml.dom` --- The Document Object Model API
+================================================
+
+.. module:: xml.dom
+ :synopsis: Document Object Model API for Python.
+.. sectionauthor:: Paul Prescod <paul@prescod.net>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.0
+
+The Document Object Model, or "DOM," is a cross-language API from the World Wide
+Web Consortium (W3C) for accessing and modifying XML documents. A DOM
+implementation presents an XML document as a tree structure, or allows client
+code to build such a structure from scratch. It then gives access to the
+structure through a set of objects which provided well-known interfaces.
+
+The DOM is extremely useful for random-access applications. SAX only allows you
+a view of one bit of the document at a time. If you are looking at one SAX
+element, you have no access to another. If you are looking at a text node, you
+have no access to a containing element. When you write a SAX application, you
+need to keep track of your program's position in the document somewhere in your
+own code. SAX does not do it for you. Also, if you need to look ahead in the
+XML document, you are just out of luck.
+
+Some applications are simply impossible in an event driven model with no access
+to a tree. Of course you could build some sort of tree yourself in SAX events,
+but the DOM allows you to avoid writing that code. The DOM is a standard tree
+representation for XML data.
+
+The Document Object Model is being defined by the W3C in stages, or "levels" in
+their terminology. The Python mapping of the API is substantially based on the
+DOM Level 2 recommendation. The mapping of the Level 3 specification, currently
+only available in draft form, is being developed by the `Python XML Special
+Interest Group <http://www.python.org/sigs/xml-sig/>`_ as part of the `PyXML
+package <http://pyxml.sourceforge.net/>`_. Refer to the documentation bundled
+with that package for information on the current state of DOM Level 3 support.
+
+.. % What if your needs are somewhere between SAX and the DOM? Perhaps
+.. % you cannot afford to load the entire tree in memory but you find the
+.. % SAX model somewhat cumbersome and low-level. There is also a module
+.. % called xml.dom.pulldom that allows you to build trees of only the
+.. % parts of a document that you need structured access to. It also has
+.. % features that allow you to find your way around the DOM.
+.. % See http://www.prescod.net/python/pulldom
+
+DOM applications typically start by parsing some XML into a DOM. How this is
+accomplished is not covered at all by DOM Level 1, and Level 2 provides only
+limited improvements: There is a :class:`DOMImplementation` object class which
+provides access to :class:`Document` creation methods, but no way to access an
+XML reader/parser/Document builder in an implementation-independent way. There
+is also no well-defined way to access these methods without an existing
+:class:`Document` object. In Python, each DOM implementation will provide a
+function :func:`getDOMImplementation`. DOM Level 3 adds a Load/Store
+specification, which defines an interface to the reader, but this is not yet
+available in the Python standard library.
+
+Once you have a DOM document object, you can access the parts of your XML
+document through its properties and methods. These properties are defined in
+the DOM specification; this portion of the reference manual describes the
+interpretation of the specification in Python.
+
+The specification provided by the W3C defines the DOM API for Java, ECMAScript,
+and OMG IDL. The Python mapping defined here is based in large part on the IDL
+version of the specification, but strict compliance is not required (though
+implementations are free to support the strict mapping from IDL). See section
+:ref:`dom-conformance` for a detailed discussion of mapping requirements.
+
+
+.. seealso::
+
+ `Document Object Model (DOM) Level 2 Specification <http://www.w3.org/TR/DOM-Level-2-Core/>`_
+ The W3C recommendation upon which the Python DOM API is based.
+
+ `Document Object Model (DOM) Level 1 Specification <http://www.w3.org/TR/REC-DOM-Level-1/>`_
+ The W3C recommendation for the DOM supported by :mod:`xml.dom.minidom`.
+
+ `PyXML <http://pyxml.sourceforge.net>`_
+ Users that require a full-featured implementation of DOM should use the PyXML
+ package.
+
+ `Python Language Mapping Specification <http://www.omg.org/docs/formal/02-11-05.pdf>`_
+ This specifies the mapping from OMG IDL to Python.
+
+
+Module Contents
+---------------
+
+The :mod:`xml.dom` contains the following functions:
+
+
+.. function:: registerDOMImplementation(name, factory)
+
+ Register the *factory* function with the name *name*. The factory function
+ should return an object which implements the :class:`DOMImplementation`
+ interface. The factory function can return the same object every time, or a new
+ one for each call, as appropriate for the specific implementation (e.g. if that
+ implementation supports some customization).
+
+
+.. function:: getDOMImplementation([name[, features]])
+
+ Return a suitable DOM implementation. The *name* is either well-known, the
+ module name of a DOM implementation, or ``None``. If it is not ``None``, imports
+ the corresponding module and returns a :class:`DOMImplementation` object if the
+ import succeeds. If no name is given, and if the environment variable
+ :envvar:`PYTHON_DOM` is set, this variable is used to find the implementation.
+
+ If name is not given, this examines the available implementations to find one
+ with the required feature set. If no implementation can be found, raise an
+ :exc:`ImportError`. The features list must be a sequence of ``(feature,
+ version)`` pairs which are passed to the :meth:`hasFeature` method on available
+ :class:`DOMImplementation` objects.
+
+Some convenience constants are also provided:
+
+
+.. data:: EMPTY_NAMESPACE
+
+ The value used to indicate that no namespace is associated with a node in the
+ DOM. This is typically found as the :attr:`namespaceURI` of a node, or used as
+ the *namespaceURI* parameter to a namespaces-specific method.
+
+ .. versionadded:: 2.2
+
+
+.. data:: XML_NAMESPACE
+
+ The namespace URI associated with the reserved prefix ``xml``, as defined by
+ `Namespaces in XML <http://www.w3.org/TR/REC-xml-names/>`_ (section 4).
+
+ .. versionadded:: 2.2
+
+
+.. data:: XMLNS_NAMESPACE
+
+ The namespace URI for namespace declarations, as defined by `Document Object
+ Model (DOM) Level 2 Core Specification
+ <http://www.w3.org/TR/DOM-Level-2-Core/core.html>`_ (section 1.1.8).
+
+ .. versionadded:: 2.2
+
+
+.. data:: XHTML_NAMESPACE
+
+ The URI of the XHTML namespace as defined by `XHTML 1.0: The Extensible
+ HyperText Markup Language <http://www.w3.org/TR/xhtml1/>`_ (section 3.1.1).
+
+ .. versionadded:: 2.2
+
+In addition, :mod:`xml.dom` contains a base :class:`Node` class and the DOM
+exception classes. The :class:`Node` class provided by this module does not
+implement any of the methods or attributes defined by the DOM specification;
+concrete DOM implementations must provide those. The :class:`Node` class
+provided as part of this module does provide the constants used for the
+:attr:`nodeType` attribute on concrete :class:`Node` objects; they are located
+within the class rather than at the module level to conform with the DOM
+specifications.
+
+.. % Should the Node documentation go here?
+
+
+.. _dom-objects:
+
+Objects in the DOM
+------------------
+
+The definitive documentation for the DOM is the DOM specification from the W3C.
+
+Note that DOM attributes may also be manipulated as nodes instead of as simple
+strings. It is fairly rare that you must do this, however, so this usage is not
+yet documented.
+
++--------------------------------+-----------------------------------+---------------------------------+
+| Interface | Section | Purpose |
++================================+===================================+=================================+
+| :class:`DOMImplementation` | :ref:`dom-implementation-objects` | Interface to the underlying |
+| | | implementation. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`Node` | :ref:`dom-node-objects` | Base interface for most objects |
+| | | in a document. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`NodeList` | :ref:`dom-nodelist-objects` | Interface for a sequence of |
+| | | nodes. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`DocumentType` | :ref:`dom-documenttype-objects` | Information about the |
+| | | declarations needed to process |
+| | | a document. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`Document` | :ref:`dom-document-objects` | Object which represents an |
+| | | entire document. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`Element` | :ref:`dom-element-objects` | Element nodes in the document |
+| | | hierarchy. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`Attr` | :ref:`dom-attr-objects` | Attribute value nodes on |
+| | | element nodes. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`Comment` | :ref:`dom-comment-objects` | Representation of comments in |
+| | | the source document. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`Text` | :ref:`dom-text-objects` | Nodes containing textual |
+| | | content from the document. |
++--------------------------------+-----------------------------------+---------------------------------+
+| :class:`ProcessingInstruction` | :ref:`dom-pi-objects` | Processing instruction |
+| | | representation. |
++--------------------------------+-----------------------------------+---------------------------------+
+
+An additional section describes the exceptions defined for working with the DOM
+in Python.
+
+
+.. _dom-implementation-objects:
+
+DOMImplementation Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The :class:`DOMImplementation` interface provides a way for applications to
+determine the availability of particular features in the DOM they are using.
+DOM Level 2 added the ability to create new :class:`Document` and
+:class:`DocumentType` objects using the :class:`DOMImplementation` as well.
+
+
+.. method:: DOMImplementation.hasFeature(feature, version)
+
+ Return true if the feature identified by the pair of strings *feature* and
+ *version* is implemented.
+
+
+.. method:: DOMImplementation.createDocument(namespaceUri, qualifiedName, doctype)
+
+ Return a new :class:`Document` object (the root of the DOM), with a child
+ :class:`Element` object having the given *namespaceUri* and *qualifiedName*. The
+ *doctype* must be a :class:`DocumentType` object created by
+ :meth:`createDocumentType`, or ``None``. In the Python DOM API, the first two
+ arguments can also be ``None`` in order to indicate that no :class:`Element`
+ child is to be created.
+
+
+.. method:: DOMImplementation.createDocumentType(qualifiedName, publicId, systemId)
+
+ Return a new :class:`DocumentType` object that encapsulates the given
+ *qualifiedName*, *publicId*, and *systemId* strings, representing the
+ information contained in an XML document type declaration.
+
+
+.. _dom-node-objects:
+
+Node Objects
+^^^^^^^^^^^^
+
+All of the components of an XML document are subclasses of :class:`Node`.
+
+
+.. attribute:: Node.nodeType
+
+ An integer representing the node type. Symbolic constants for the types are on
+ the :class:`Node` object: :const:`ELEMENT_NODE`, :const:`ATTRIBUTE_NODE`,
+ :const:`TEXT_NODE`, :const:`CDATA_SECTION_NODE`, :const:`ENTITY_NODE`,
+ :const:`PROCESSING_INSTRUCTION_NODE`, :const:`COMMENT_NODE`,
+ :const:`DOCUMENT_NODE`, :const:`DOCUMENT_TYPE_NODE`, :const:`NOTATION_NODE`.
+ This is a read-only attribute.
+
+
+.. attribute:: Node.parentNode
+
+ The parent of the current node, or ``None`` for the document node. The value is
+ always a :class:`Node` object or ``None``. For :class:`Element` nodes, this
+ will be the parent element, except for the root element, in which case it will
+ be the :class:`Document` object. For :class:`Attr` nodes, this is always
+ ``None``. This is a read-only attribute.
+
+
+.. attribute:: Node.attributes
+
+ A :class:`NamedNodeMap` of attribute objects. Only elements have actual values
+ for this; others provide ``None`` for this attribute. This is a read-only
+ attribute.
+
+
+.. attribute:: Node.previousSibling
+
+ The node that immediately precedes this one with the same parent. For
+ instance the element with an end-tag that comes just before the *self*
+ element's start-tag. Of course, XML documents are made up of more than just
+ elements so the previous sibling could be text, a comment, or something else.
+ If this node is the first child of the parent, this attribute will be
+ ``None``. This is a read-only attribute.
+
+
+.. attribute:: Node.nextSibling
+
+ The node that immediately follows this one with the same parent. See also
+ :attr:`previousSibling`. If this is the last child of the parent, this
+ attribute will be ``None``. This is a read-only attribute.
+
+
+.. attribute:: Node.childNodes
+
+ A list of nodes contained within this node. This is a read-only attribute.
+
+
+.. attribute:: Node.firstChild
+
+ The first child of the node, if there are any, or ``None``. This is a read-only
+ attribute.
+
+
+.. attribute:: Node.lastChild
+
+ The last child of the node, if there are any, or ``None``. This is a read-only
+ attribute.
+
+
+.. attribute:: Node.localName
+
+ The part of the :attr:`tagName` following the colon if there is one, else the
+ entire :attr:`tagName`. The value is a string.
+
+
+.. attribute:: Node.prefix
+
+ The part of the :attr:`tagName` preceding the colon if there is one, else the
+ empty string. The value is a string, or ``None``
+
+
+.. attribute:: Node.namespaceURI
+
+ The namespace associated with the element name. This will be a string or
+ ``None``. This is a read-only attribute.
+
+
+.. attribute:: Node.nodeName
+
+ This has a different meaning for each node type; see the DOM specification for
+ details. You can always get the information you would get here from another
+ property such as the :attr:`tagName` property for elements or the :attr:`name`
+ property for attributes. For all node types, the value of this attribute will be
+ either a string or ``None``. This is a read-only attribute.
+
+
+.. attribute:: Node.nodeValue
+
+ This has a different meaning for each node type; see the DOM specification for
+ details. The situation is similar to that with :attr:`nodeName`. The value is
+ a string or ``None``.
+
+
+.. method:: Node.hasAttributes()
+
+ Returns true if the node has any attributes.
+
+
+.. method:: Node.hasChildNodes()
+
+ Returns true if the node has any child nodes.
+
+
+.. method:: Node.isSameNode(other)
+
+ Returns true if *other* refers to the same node as this node. This is especially
+ useful for DOM implementations which use any sort of proxy architecture (because
+ more than one object can refer to the same node).
+
+ .. note::
+
+ This is based on a proposed DOM Level 3 API which is still in the "working
+ draft" stage, but this particular interface appears uncontroversial. Changes
+ from the W3C will not necessarily affect this method in the Python DOM interface
+ (though any new W3C API for this would also be supported).
+
+
+.. method:: Node.appendChild(newChild)
+
+ Add a new child node to this node at the end of the list of children, returning
+ *newChild*.
+
+
+.. method:: Node.insertBefore(newChild, refChild)
+
+ Insert a new child node before an existing child. It must be the case that
+ *refChild* is a child of this node; if not, :exc:`ValueError` is raised.
+ *newChild* is returned. If *refChild* is ``None``, it inserts *newChild* at the
+ end of the children's list.
+
+
+.. method:: Node.removeChild(oldChild)
+
+ Remove a child node. *oldChild* must be a child of this node; if not,
+ :exc:`ValueError` is raised. *oldChild* is returned on success. If *oldChild*
+ will not be used further, its :meth:`unlink` method should be called.
+
+
+.. method:: Node.replaceChild(newChild, oldChild)
+
+ Replace an existing node with a new node. It must be the case that *oldChild*
+ is a child of this node; if not, :exc:`ValueError` is raised.
+
+
+.. method:: Node.normalize()
+
+ Join adjacent text nodes so that all stretches of text are stored as single
+ :class:`Text` instances. This simplifies processing text from a DOM tree for
+ many applications.
+
+ .. versionadded:: 2.1
+
+
+.. method:: Node.cloneNode(deep)
+
+ Clone this node. Setting *deep* means to clone all child nodes as well. This
+ returns the clone.
+
+
+.. _dom-nodelist-objects:
+
+NodeList Objects
+^^^^^^^^^^^^^^^^
+
+A :class:`NodeList` represents a sequence of nodes. These objects are used in
+two ways in the DOM Core recommendation: the :class:`Element` objects provides
+one as its list of child nodes, and the :meth:`getElementsByTagName` and
+:meth:`getElementsByTagNameNS` methods of :class:`Node` return objects with this
+interface to represent query results.
+
+The DOM Level 2 recommendation defines one method and one attribute for these
+objects:
+
+
+.. method:: NodeList.item(i)
+
+ Return the *i*'th item from the sequence, if there is one, or ``None``. The
+ index *i* is not allowed to be less then zero or greater than or equal to the
+ length of the sequence.
+
+
+.. attribute:: NodeList.length
+
+ The number of nodes in the sequence.
+
+In addition, the Python DOM interface requires that some additional support is
+provided to allow :class:`NodeList` objects to be used as Python sequences. All
+:class:`NodeList` implementations must include support for :meth:`__len__` and
+:meth:`__getitem__`; this allows iteration over the :class:`NodeList` in
+:keyword:`for` statements and proper support for the :func:`len` built-in
+function.
+
+If a DOM implementation supports modification of the document, the
+:class:`NodeList` implementation must also support the :meth:`__setitem__` and
+:meth:`__delitem__` methods.
+
+
+.. _dom-documenttype-objects:
+
+DocumentType Objects
+^^^^^^^^^^^^^^^^^^^^
+
+Information about the notations and entities declared by a document (including
+the external subset if the parser uses it and can provide the information) is
+available from a :class:`DocumentType` object. The :class:`DocumentType` for a
+document is available from the :class:`Document` object's :attr:`doctype`
+attribute; if there is no ``DOCTYPE`` declaration for the document, the
+document's :attr:`doctype` attribute will be set to ``None`` instead of an
+instance of this interface.
+
+:class:`DocumentType` is a specialization of :class:`Node`, and adds the
+following attributes:
+
+
+.. attribute:: DocumentType.publicId
+
+ The public identifier for the external subset of the document type definition.
+ This will be a string or ``None``.
+
+
+.. attribute:: DocumentType.systemId
+
+ The system identifier for the external subset of the document type definition.
+ This will be a URI as a string, or ``None``.
+
+
+.. attribute:: DocumentType.internalSubset
+
+ A string giving the complete internal subset from the document. This does not
+ include the brackets which enclose the subset. If the document has no internal
+ subset, this should be ``None``.
+
+
+.. attribute:: DocumentType.name
+
+ The name of the root element as given in the ``DOCTYPE`` declaration, if
+ present.
+
+
+.. attribute:: DocumentType.entities
+
+ This is a :class:`NamedNodeMap` giving the definitions of external entities.
+ For entity names defined more than once, only the first definition is provided
+ (others are ignored as required by the XML recommendation). This may be
+ ``None`` if the information is not provided by the parser, or if no entities are
+ defined.
+
+
+.. attribute:: DocumentType.notations
+
+ This is a :class:`NamedNodeMap` giving the definitions of notations. For
+ notation names defined more than once, only the first definition is provided
+ (others are ignored as required by the XML recommendation). This may be
+ ``None`` if the information is not provided by the parser, or if no notations
+ are defined.
+
+
+.. _dom-document-objects:
+
+Document Objects
+^^^^^^^^^^^^^^^^
+
+A :class:`Document` represents an entire XML document, including its constituent
+elements, attributes, processing instructions, comments etc. Remeber that it
+inherits properties from :class:`Node`.
+
+
+.. attribute:: Document.documentElement
+
+ The one and only root element of the document.
+
+
+.. method:: Document.createElement(tagName)
+
+ Create and return a new element node. The element is not inserted into the
+ document when it is created. You need to explicitly insert it with one of the
+ other methods such as :meth:`insertBefore` or :meth:`appendChild`.
+
+
+.. method:: Document.createElementNS(namespaceURI, tagName)
+
+ Create and return a new element with a namespace. The *tagName* may have a
+ prefix. The element is not inserted into the document when it is created. You
+ need to explicitly insert it with one of the other methods such as
+ :meth:`insertBefore` or :meth:`appendChild`.
+
+
+.. method:: Document.createTextNode(data)
+
+ Create and return a text node containing the data passed as a parameter. As
+ with the other creation methods, this one does not insert the node into the
+ tree.
+
+
+.. method:: Document.createComment(data)
+
+ Create and return a comment node containing the data passed as a parameter. As
+ with the other creation methods, this one does not insert the node into the
+ tree.
+
+
+.. method:: Document.createProcessingInstruction(target, data)
+
+ Create and return a processing instruction node containing the *target* and
+ *data* passed as parameters. As with the other creation methods, this one does
+ not insert the node into the tree.
+
+
+.. method:: Document.createAttribute(name)
+
+ Create and return an attribute node. This method does not associate the
+ attribute node with any particular element. You must use
+ :meth:`setAttributeNode` on the appropriate :class:`Element` object to use the
+ newly created attribute instance.
+
+
+.. method:: Document.createAttributeNS(namespaceURI, qualifiedName)
+
+ Create and return an attribute node with a namespace. The *tagName* may have a
+ prefix. This method does not associate the attribute node with any particular
+ element. You must use :meth:`setAttributeNode` on the appropriate
+ :class:`Element` object to use the newly created attribute instance.
+
+
+.. method:: Document.getElementsByTagName(tagName)
+
+ Search for all descendants (direct children, children's children, etc.) with a
+ particular element type name.
+
+
+.. method:: Document.getElementsByTagNameNS(namespaceURI, localName)
+
+ Search for all descendants (direct children, children's children, etc.) with a
+ particular namespace URI and localname. The localname is the part of the
+ namespace after the prefix.
+
+
+.. _dom-element-objects:
+
+Element Objects
+^^^^^^^^^^^^^^^
+
+:class:`Element` is a subclass of :class:`Node`, so inherits all the attributes
+of that class.
+
+
+.. attribute:: Element.tagName
+
+ The element type name. In a namespace-using document it may have colons in it.
+ The value is a string.
+
+
+.. method:: Element.getElementsByTagName(tagName)
+
+ Same as equivalent method in the :class:`Document` class.
+
+
+.. method:: Element.getElementsByTagNameNS(tagName)
+
+ Same as equivalent method in the :class:`Document` class.
+
+
+.. method:: Element.hasAttribute(name)
+
+ Returns true if the element has an attribute named by *name*.
+
+
+.. method:: Element.hasAttributeNS(namespaceURI, localName)
+
+ Returns true if the element has an attribute named by *namespaceURI* and
+ *localName*.
+
+
+.. method:: Element.getAttribute(name)
+
+ Return the value of the attribute named by *name* as a string. If no such
+ attribute exists, an empty string is returned, as if the attribute had no value.
+
+
+.. method:: Element.getAttributeNode(attrname)
+
+ Return the :class:`Attr` node for the attribute named by *attrname*.
+
+
+.. method:: Element.getAttributeNS(namespaceURI, localName)
+
+ Return the value of the attribute named by *namespaceURI* and *localName* as a
+ string. If no such attribute exists, an empty string is returned, as if the
+ attribute had no value.
+
+
+.. method:: Element.getAttributeNodeNS(namespaceURI, localName)
+
+ Return an attribute value as a node, given a *namespaceURI* and *localName*.
+
+
+.. method:: Element.removeAttribute(name)
+
+ Remove an attribute by name. No exception is raised if there is no matching
+ attribute.
+
+
+.. method:: Element.removeAttributeNode(oldAttr)
+
+ Remove and return *oldAttr* from the attribute list, if present. If *oldAttr* is
+ not present, :exc:`NotFoundErr` is raised.
+
+
+.. method:: Element.removeAttributeNS(namespaceURI, localName)
+
+ Remove an attribute by name. Note that it uses a localName, not a qname. No
+ exception is raised if there is no matching attribute.
+
+
+.. method:: Element.setAttribute(name, value)
+
+ Set an attribute value from a string.
+
+
+.. method:: Element.setAttributeNode(newAttr)
+
+ Add a new attribute node to the element, replacing an existing attribute if
+ necessary if the :attr:`name` attribute matches. If a replacement occurs, the
+ old attribute node will be returned. If *newAttr* is already in use,
+ :exc:`InuseAttributeErr` will be raised.
+
+
+.. method:: Element.setAttributeNodeNS(newAttr)
+
+ Add a new attribute node to the element, replacing an existing attribute if
+ necessary if the :attr:`namespaceURI` and :attr:`localName` attributes match.
+ If a replacement occurs, the old attribute node will be returned. If *newAttr*
+ is already in use, :exc:`InuseAttributeErr` will be raised.
+
+
+.. method:: Element.setAttributeNS(namespaceURI, qname, value)
+
+ Set an attribute value from a string, given a *namespaceURI* and a *qname*.
+ Note that a qname is the whole attribute name. This is different than above.
+
+
+.. _dom-attr-objects:
+
+Attr Objects
+^^^^^^^^^^^^
+
+:class:`Attr` inherits from :class:`Node`, so inherits all its attributes.
+
+
+.. attribute:: Attr.name
+
+ The attribute name. In a namespace-using document it may have colons in it.
+
+
+.. attribute:: Attr.localName
+
+ The part of the name following the colon if there is one, else the entire name.
+ This is a read-only attribute.
+
+
+.. attribute:: Attr.prefix
+
+ The part of the name preceding the colon if there is one, else the empty string.
+
+
+.. _dom-attributelist-objects:
+
+NamedNodeMap Objects
+^^^^^^^^^^^^^^^^^^^^
+
+:class:`NamedNodeMap` does *not* inherit from :class:`Node`.
+
+
+.. attribute:: NamedNodeMap.length
+
+ The length of the attribute list.
+
+
+.. method:: NamedNodeMap.item(index)
+
+ Return an attribute with a particular index. The order you get the attributes
+ in is arbitrary but will be consistent for the life of a DOM. Each item is an
+ attribute node. Get its value with the :attr:`value` attribute.
+
+There are also experimental methods that give this class more mapping behavior.
+You can use them or you can use the standardized :meth:`getAttribute\*` family
+of methods on the :class:`Element` objects.
+
+
+.. _dom-comment-objects:
+
+Comment Objects
+^^^^^^^^^^^^^^^
+
+:class:`Comment` represents a comment in the XML document. It is a subclass of
+:class:`Node`, but cannot have child nodes.
+
+
+.. attribute:: Comment.data
+
+ The content of the comment as a string. The attribute contains all characters
+ between the leading ``<!-``\ ``-`` and trailing ``-``\ ``->``, but does not
+ include them.
+
+
+.. _dom-text-objects:
+
+Text and CDATASection Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The :class:`Text` interface represents text in the XML document. If the parser
+and DOM implementation support the DOM's XML extension, portions of the text
+enclosed in CDATA marked sections are stored in :class:`CDATASection` objects.
+These two interfaces are identical, but provide different values for the
+:attr:`nodeType` attribute.
+
+These interfaces extend the :class:`Node` interface. They cannot have child
+nodes.
+
+
+.. attribute:: Text.data
+
+ The content of the text node as a string.
+
+.. note::
+
+ The use of a :class:`CDATASection` node does not indicate that the node
+ represents a complete CDATA marked section, only that the content of the node
+ was part of a CDATA section. A single CDATA section may be represented by more
+ than one node in the document tree. There is no way to determine whether two
+ adjacent :class:`CDATASection` nodes represent different CDATA marked sections.
+
+
+.. _dom-pi-objects:
+
+ProcessingInstruction Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Represents a processing instruction in the XML document; this inherits from the
+:class:`Node` interface and cannot have child nodes.
+
+
+.. attribute:: ProcessingInstruction.target
+
+ The content of the processing instruction up to the first whitespace character.
+ This is a read-only attribute.
+
+
+.. attribute:: ProcessingInstruction.data
+
+ The content of the processing instruction following the first whitespace
+ character.
+
+
+.. _dom-exceptions:
+
+Exceptions
+^^^^^^^^^^
+
+.. versionadded:: 2.1
+
+The DOM Level 2 recommendation defines a single exception, :exc:`DOMException`,
+and a number of constants that allow applications to determine what sort of
+error occurred. :exc:`DOMException` instances carry a :attr:`code` attribute
+that provides the appropriate value for the specific exception.
+
+The Python DOM interface provides the constants, but also expands the set of
+exceptions so that a specific exception exists for each of the exception codes
+defined by the DOM. The implementations must raise the appropriate specific
+exception, each of which carries the appropriate value for the :attr:`code`
+attribute.
+
+
+.. exception:: DOMException
+
+ Base exception class used for all specific DOM exceptions. This exception class
+ cannot be directly instantiated.
+
+
+.. exception:: DomstringSizeErr
+
+ Raised when a specified range of text does not fit into a string. This is not
+ known to be used in the Python DOM implementations, but may be received from DOM
+ implementations not written in Python.
+
+
+.. exception:: HierarchyRequestErr
+
+ Raised when an attempt is made to insert a node where the node type is not
+ allowed.
+
+
+.. exception:: IndexSizeErr
+
+ Raised when an index or size parameter to a method is negative or exceeds the
+ allowed values.
+
+
+.. exception:: InuseAttributeErr
+
+ Raised when an attempt is made to insert an :class:`Attr` node that is already
+ present elsewhere in the document.
+
+
+.. exception:: InvalidAccessErr
+
+ Raised if a parameter or an operation is not supported on the underlying object.
+
+
+.. exception:: InvalidCharacterErr
+
+ This exception is raised when a string parameter contains a character that is
+ not permitted in the context it's being used in by the XML 1.0 recommendation.
+ For example, attempting to create an :class:`Element` node with a space in the
+ element type name will cause this error to be raised.
+
+
+.. exception:: InvalidModificationErr
+
+ Raised when an attempt is made to modify the type of a node.
+
+
+.. exception:: InvalidStateErr
+
+ Raised when an attempt is made to use an object that is not defined or is no
+ longer usable.
+
+
+.. exception:: NamespaceErr
+
+ If an attempt is made to change any object in a way that is not permitted with
+ regard to the `Namespaces in XML <http://www.w3.org/TR/REC-xml-names/>`_
+ recommendation, this exception is raised.
+
+
+.. exception:: NotFoundErr
+
+ Exception when a node does not exist in the referenced context. For example,
+ :meth:`NamedNodeMap.removeNamedItem` will raise this if the node passed in does
+ not exist in the map.
+
+
+.. exception:: NotSupportedErr
+
+ Raised when the implementation does not support the requested type of object or
+ operation.
+
+
+.. exception:: NoDataAllowedErr
+
+ This is raised if data is specified for a node which does not support data.
+
+ .. % XXX a better explanation is needed!
+
+
+.. exception:: NoModificationAllowedErr
+
+ Raised on attempts to modify an object where modifications are not allowed (such
+ as for read-only nodes).
+
+
+.. exception:: SyntaxErr
+
+ Raised when an invalid or illegal string is specified.
+
+ .. % XXX how is this different from InvalidCharacterErr ???
+
+
+.. exception:: WrongDocumentErr
+
+ Raised when a node is inserted in a different document than it currently belongs
+ to, and the implementation does not support migrating the node from one document
+ to the other.
+
+The exception codes defined in the DOM recommendation map to the exceptions
+described above according to this table:
+
++--------------------------------------+---------------------------------+
+| Constant | Exception |
++======================================+=================================+
+| :const:`DOMSTRING_SIZE_ERR` | :exc:`DomstringSizeErr` |
++--------------------------------------+---------------------------------+
+| :const:`HIERARCHY_REQUEST_ERR` | :exc:`HierarchyRequestErr` |
++--------------------------------------+---------------------------------+
+| :const:`INDEX_SIZE_ERR` | :exc:`IndexSizeErr` |
++--------------------------------------+---------------------------------+
+| :const:`INUSE_ATTRIBUTE_ERR` | :exc:`InuseAttributeErr` |
++--------------------------------------+---------------------------------+
+| :const:`INVALID_ACCESS_ERR` | :exc:`InvalidAccessErr` |
++--------------------------------------+---------------------------------+
+| :const:`INVALID_CHARACTER_ERR` | :exc:`InvalidCharacterErr` |
++--------------------------------------+---------------------------------+
+| :const:`INVALID_MODIFICATION_ERR` | :exc:`InvalidModificationErr` |
++--------------------------------------+---------------------------------+
+| :const:`INVALID_STATE_ERR` | :exc:`InvalidStateErr` |
++--------------------------------------+---------------------------------+
+| :const:`NAMESPACE_ERR` | :exc:`NamespaceErr` |
++--------------------------------------+---------------------------------+
+| :const:`NOT_FOUND_ERR` | :exc:`NotFoundErr` |
++--------------------------------------+---------------------------------+
+| :const:`NOT_SUPPORTED_ERR` | :exc:`NotSupportedErr` |
++--------------------------------------+---------------------------------+
+| :const:`NO_DATA_ALLOWED_ERR` | :exc:`NoDataAllowedErr` |
++--------------------------------------+---------------------------------+
+| :const:`NO_MODIFICATION_ALLOWED_ERR` | :exc:`NoModificationAllowedErr` |
++--------------------------------------+---------------------------------+
+| :const:`SYNTAX_ERR` | :exc:`SyntaxErr` |
++--------------------------------------+---------------------------------+
+| :const:`WRONG_DOCUMENT_ERR` | :exc:`WrongDocumentErr` |
++--------------------------------------+---------------------------------+
+
+
+.. _dom-conformance:
+
+Conformance
+-----------
+
+This section describes the conformance requirements and relationships between
+the Python DOM API, the W3C DOM recommendations, and the OMG IDL mapping for
+Python.
+
+
+.. _dom-type-mapping:
+
+Type Mapping
+^^^^^^^^^^^^
+
+The primitive IDL types used in the DOM specification are mapped to Python types
+according to the following table.
+
++------------------+-------------------------------------------+
+| IDL Type | Python Type |
++==================+===========================================+
+| ``boolean`` | ``IntegerType`` (with a value of ``0`` or |
+| | ``1``) |
++------------------+-------------------------------------------+
+| ``int`` | ``IntegerType`` |
++------------------+-------------------------------------------+
+| ``long int`` | ``IntegerType`` |
++------------------+-------------------------------------------+
+| ``unsigned int`` | ``IntegerType`` |
++------------------+-------------------------------------------+
+
+Additionally, the :class:`DOMString` defined in the recommendation is mapped to
+a Python string or Unicode string. Applications should be able to handle
+Unicode whenever a string is returned from the DOM.
+
+The IDL :keyword:`null` value is mapped to ``None``, which may be accepted or
+provided by the implementation whenever :keyword:`null` is allowed by the API.
+
+
+.. _dom-accessor-methods:
+
+Accessor Methods
+^^^^^^^^^^^^^^^^
+
+The mapping from OMG IDL to Python defines accessor functions for IDL
+:keyword:`attribute` declarations in much the way the Java mapping does.
+Mapping the IDL declarations ::
+
+ readonly attribute string someValue;
+ attribute string anotherValue;
+
+yields three accessor functions: a "get" method for :attr:`someValue`
+(:meth:`_get_someValue`), and "get" and "set" methods for :attr:`anotherValue`
+(:meth:`_get_anotherValue` and :meth:`_set_anotherValue`). The mapping, in
+particular, does not require that the IDL attributes are accessible as normal
+Python attributes: ``object.someValue`` is *not* required to work, and may
+raise an :exc:`AttributeError`.
+
+The Python DOM API, however, *does* require that normal attribute access work.
+This means that the typical surrogates generated by Python IDL compilers are not
+likely to work, and wrapper objects may be needed on the client if the DOM
+objects are accessed via CORBA. While this does require some additional
+consideration for CORBA DOM clients, the implementers with experience using DOM
+over CORBA from Python do not consider this a problem. Attributes that are
+declared :keyword:`readonly` may not restrict write access in all DOM
+implementations.
+
+In the Python DOM API, accessor functions are not required. If provided, they
+should take the form defined by the Python IDL mapping, but these methods are
+considered unnecessary since the attributes are accessible directly from Python.
+"Set" accessors should never be provided for :keyword:`readonly` attributes.
+
+The IDL definitions do not fully embody the requirements of the W3C DOM API,
+such as the notion of certain objects, such as the return value of
+:meth:`getElementsByTagName`, being "live". The Python DOM API does not require
+implementations to enforce such requirements.
+
diff --git a/Doc/library/xml.etree.elementtree.rst b/Doc/library/xml.etree.elementtree.rst
new file mode 100644
index 0000000000..ead8d29182
--- /dev/null
+++ b/Doc/library/xml.etree.elementtree.rst
@@ -0,0 +1,444 @@
+
+:mod:`xml.etree.ElementTree` --- The ElementTree XML API
+========================================================
+
+.. module:: xml.etree.ElementTree
+ :synopsis: Implementation of the ElementTree API.
+.. moduleauthor:: Fredrik Lundh <fredrik@pythonware.com>
+
+
+.. versionadded:: 2.5
+
+The Element type is a flexible container object, designed to store hierarchical
+data structures in memory. The type can be described as a cross between a list
+and a dictionary.
+
+Each element has a number of properties associated with it:
+
+* a tag which is a string identifying what kind of data this element represents
+ (the element type, in other words).
+
+* a number of attributes, stored in a Python dictionary.
+
+* a text string.
+
+* an optional tail string.
+
+* a number of child elements, stored in a Python sequence
+
+To create an element instance, use the Element or SubElement factory functions.
+
+The :class:`ElementTree` class can be used to wrap an element structure, and
+convert it from and to XML.
+
+A C implementation of this API is available as :mod:`xml.etree.cElementTree`.
+
+
+.. _elementtree-functions:
+
+Functions
+---------
+
+
+.. function:: Comment([text])
+
+ Comment element factory. This factory function creates a special element that
+ will be serialized as an XML comment. The comment string can be either an 8-bit
+ ASCII string or a Unicode string. *text* is a string containing the comment
+ string. Returns an element instance representing a comment.
+
+
+.. function:: dump(elem)
+
+ Writes an element tree or element structure to sys.stdout. This function should
+ be used for debugging only.
+
+ The exact output format is implementation dependent. In this version, it's
+ written as an ordinary XML file.
+
+ *elem* is an element tree or an individual element.
+
+
+.. function:: Element(tag[, attrib][, **extra])
+
+ Element factory. This function returns an object implementing the standard
+ Element interface. The exact class or type of that object is implementation
+ dependent, but it will always be compatible with the _ElementInterface class in
+ this module.
+
+ The element name, attribute names, and attribute values can be either 8-bit
+ ASCII strings or Unicode strings. *tag* is the element name. *attrib* is an
+ optional dictionary, containing element attributes. *extra* contains additional
+ attributes, given as keyword arguments. Returns an element instance.
+
+
+.. function:: fromstring(text)
+
+ Parses an XML section from a string constant. Same as XML. *text* is a string
+ containing XML data. Returns an Element instance.
+
+
+.. function:: iselement(element)
+
+ Checks if an object appears to be a valid element object. *element* is an
+ element instance. Returns a true value if this is an element object.
+
+
+.. function:: iterparse(source[, events])
+
+ Parses an XML section into an element tree incrementally, and reports what's
+ going on to the user. *source* is a filename or file object containing XML data.
+ *events* is a list of events to report back. If omitted, only "end" events are
+ reported. Returns an iterator providing ``(event, elem)`` pairs.
+
+
+.. function:: parse(source[, parser])
+
+ Parses an XML section into an element tree. *source* is a filename or file
+ object containing XML data. *parser* is an optional parser instance. If not
+ given, the standard XMLTreeBuilder parser is used. Returns an ElementTree
+ instance.
+
+
+.. function:: ProcessingInstruction(target[, text])
+
+ PI element factory. This factory function creates a special element that will
+ be serialized as an XML processing instruction. *target* is a string containing
+ the PI target. *text* is a string containing the PI contents, if given. Returns
+ an element instance, representing a processing instruction.
+
+
+.. function:: SubElement(parent, tag[, attrib[, **extra]])
+
+ Subelement factory. This function creates an element instance, and appends it
+ to an existing element.
+
+ The element name, attribute names, and attribute values can be either 8-bit
+ ASCII strings or Unicode strings. *parent* is the parent element. *tag* is the
+ subelement name. *attrib* is an optional dictionary, containing element
+ attributes. *extra* contains additional attributes, given as keyword arguments.
+ Returns an element instance.
+
+
+.. function:: tostring(element[, encoding])
+
+ Generates a string representation of an XML element, including all subelements.
+ *element* is an Element instance. *encoding* is the output encoding (default is
+ US-ASCII). Returns an encoded string containing the XML data.
+
+
+.. function:: XML(text)
+
+ Parses an XML section from a string constant. This function can be used to
+ embed "XML literals" in Python code. *text* is a string containing XML data.
+ Returns an Element instance.
+
+
+.. function:: XMLID(text)
+
+ Parses an XML section from a string constant, and also returns a dictionary
+ which maps from element id:s to elements. *text* is a string containing XML
+ data. Returns a tuple containing an Element instance and a dictionary.
+
+
+.. _elementtree-element-interface:
+
+The Element Interface
+---------------------
+
+Element objects returned by Element or SubElement have the following methods
+and attributes.
+
+
+.. attribute:: Element.tag
+
+ A string identifying what kind of data this element represents (the element
+ type, in other words).
+
+
+.. attribute:: Element.text
+
+ The *text* attribute can be used to hold additional data associated with the
+ element. As the name implies this attribute is usually a string but may be any
+ application-specific object. If the element is created from an XML file the
+ attribute will contain any text found between the element tags.
+
+
+.. attribute:: Element.tail
+
+ The *tail* attribute can be used to hold additional data associated with the
+ element. This attribute is usually a string but may be any application-specific
+ object. If the element is created from an XML file the attribute will contain
+ any text found after the element's end tag and before the next tag.
+
+
+.. attribute:: Element.attrib
+
+ A dictionary containing the element's attributes. Note that while the *attrib*
+ value is always a real mutable Python dictionary, an ElementTree implementation
+ may choose to use another internal representation, and create the dictionary
+ only if someone asks for it. To take advantage of such implementations, use the
+ dictionary methods below whenever possible.
+
+The following dictionary-like methods work on the element attributes.
+
+
+.. method:: Element.clear()
+
+ Resets an element. This function removes all subelements, clears all
+ attributes, and sets the text and tail attributes to None.
+
+
+.. method:: Element.get(key[, default=None])
+
+ Gets the element attribute named *key*.
+
+ Returns the attribute value, or *default* if the attribute was not found.
+
+
+.. method:: Element.items()
+
+ Returns the element attributes as a sequence of (name, value) pairs. The
+ attributes are returned in an arbitrary order.
+
+
+.. method:: Element.keys()
+
+ Returns the elements attribute names as a list. The names are returned in an
+ arbitrary order.
+
+
+.. method:: Element.set(key, value)
+
+ Set the attribute *key* on the element to *value*.
+
+The following methods work on the element's children (subelements).
+
+
+.. method:: Element.append(subelement)
+
+ Adds the element *subelement* to the end of this elements internal list of
+ subelements.
+
+
+.. method:: Element.find(match)
+
+ Finds the first subelement matching *match*. *match* may be a tag name or path.
+ Returns an element instance or ``None``.
+
+
+.. method:: Element.findall(match)
+
+ Finds all subelements matching *match*. *match* may be a tag name or path.
+ Returns an iterable yielding all matching elements in document order.
+
+
+.. method:: Element.findtext(condition[, default=None])
+
+ Finds text for the first subelement matching *condition*. *condition* may be a
+ tag name or path. Returns the text content of the first matching element, or
+ *default* if no element was found. Note that if the matching element has no
+ text content an empty string is returned.
+
+
+.. method:: Element.getchildren()
+
+ Returns all subelements. The elements are returned in document order.
+
+
+.. method:: Element.getiterator([tag=None])
+
+ Creates a tree iterator with the current element as the root. The iterator
+ iterates over this element and all elements below it that match the given tag.
+ If tag is ``None`` or ``'*'`` then all elements are iterated over. Returns an
+ iterable that provides element objects in document (depth first) order.
+
+
+.. method:: Element.insert(index, element)
+
+ Inserts a subelement at the given position in this element.
+
+
+.. method:: Element.makeelement(tag, attrib)
+
+ Creates a new element object of the same type as this element. Do not call this
+ method, use the SubElement factory function instead.
+
+
+.. method:: Element.remove(subelement)
+
+ Removes *subelement* from the element. Unlike the findXYZ methods this method
+ compares elements based on the instance identity, not on tag value or contents.
+
+Element objects also support the following sequence type methods for working
+with subelements: :meth:`__delitem__`, :meth:`__getitem__`, :meth:`__setitem__`,
+:meth:`__len__`.
+
+Caution: Because Element objects do not define a :meth:`__nonzero__` method,
+elements with no subelements will test as ``False``. ::
+
+ element = root.find('foo')
+
+ if not element: # careful!
+ print "element not found, or element has no subelements"
+
+ if element is None:
+ print "element not found"
+
+
+.. _elementtree-elementtree-objects:
+
+ElementTree Objects
+-------------------
+
+
+.. class:: ElementTree([element,] [file])
+
+ ElementTree wrapper class. This class represents an entire element hierarchy,
+ and adds some extra support for serialization to and from standard XML.
+
+ *element* is the root element. The tree is initialized with the contents of the
+ XML *file* if given.
+
+
+.. method:: ElementTree._setroot(element)
+
+ Replaces the root element for this tree. This discards the current contents of
+ the tree, and replaces it with the given element. Use with care. *element* is
+ an element instance.
+
+
+.. method:: ElementTree.find(path)
+
+ Finds the first toplevel element with given tag. Same as getroot().find(path).
+ *path* is the element to look for. Returns the first matching element, or
+ ``None`` if no element was found.
+
+
+.. method:: ElementTree.findall(path)
+
+ Finds all toplevel elements with the given tag. Same as getroot().findall(path).
+ *path* is the element to look for. Returns a list or iterator containing all
+ matching elements, in document order.
+
+
+.. method:: ElementTree.findtext(path[, default])
+
+ Finds the element text for the first toplevel element with given tag. Same as
+ getroot().findtext(path). *path* is the toplevel element to look for. *default*
+ is the value to return if the element was not found. Returns the text content of
+ the first matching element, or the default value no element was found. Note
+ that if the element has is found, but has no text content, this method returns
+ an empty string.
+
+
+.. method:: ElementTree.getiterator([tag])
+
+ Creates and returns a tree iterator for the root element. The iterator loops
+ over all elements in this tree, in section order. *tag* is the tag to look for
+ (default is to return all elements)
+
+
+.. method:: ElementTree.getroot()
+
+ Returns the root element for this tree.
+
+
+.. method:: ElementTree.parse(source[, parser])
+
+ Loads an external XML section into this element tree. *source* is a file name or
+ file object. *parser* is an optional parser instance. If not given, the
+ standard XMLTreeBuilder parser is used. Returns the section root element.
+
+
+.. method:: ElementTree.write(file[, encoding])
+
+ Writes the element tree to a file, as XML. *file* is a file name, or a file
+ object opened for writing. *encoding* is the output encoding (default is
+ US-ASCII).
+
+
+.. _elementtree-qname-objects:
+
+QName Objects
+-------------
+
+
+.. class:: QName(text_or_uri[, tag])
+
+ QName wrapper. This can be used to wrap a QName attribute value, in order to
+ get proper namespace handling on output. *text_or_uri* is a string containing
+ the QName value, in the form {uri}local, or, if the tag argument is given, the
+ URI part of a QName. If *tag* is given, the first argument is interpreted as an
+ URI, and this argument is interpreted as a local name. :class:`QName` instances
+ are opaque.
+
+
+.. _elementtree-treebuilder-objects:
+
+TreeBuilder Objects
+-------------------
+
+
+.. class:: TreeBuilder([element_factory])
+
+ Generic element structure builder. This builder converts a sequence of start,
+ data, and end method calls to a well-formed element structure. You can use this
+ class to build an element structure using a custom XML parser, or a parser for
+ some other XML-like format. The *element_factory* is called to create new
+ Element instances when given.
+
+
+.. method:: TreeBuilder.close()
+
+ Flushes the parser buffers, and returns the toplevel documen element. Returns an
+ Element instance.
+
+
+.. method:: TreeBuilder.data(data)
+
+ Adds text to the current element. *data* is a string. This should be either an
+ 8-bit string containing ASCII text, or a Unicode string.
+
+
+.. method:: TreeBuilder.end(tag)
+
+ Closes the current element. *tag* is the element name. Returns the closed
+ element.
+
+
+.. method:: TreeBuilder.start(tag, attrs)
+
+ Opens a new element. *tag* is the element name. *attrs* is a dictionary
+ containing element attributes. Returns the opened element.
+
+
+.. _elementtree-xmltreebuilder-objects:
+
+XMLTreeBuilder Objects
+----------------------
+
+
+.. class:: XMLTreeBuilder([html,] [target])
+
+ Element structure builder for XML source data, based on the expat parser. *html*
+ are predefined HTML entities. This flag is not supported by the current
+ implementation. *target* is the target object. If omitted, the builder uses an
+ instance of the standard TreeBuilder class.
+
+
+.. method:: XMLTreeBuilder.close()
+
+ Finishes feeding data to the parser. Returns an element structure.
+
+
+.. method:: XMLTreeBuilder.doctype(name, pubid, system)
+
+ Handles a doctype declaration. *name* is the doctype name. *pubid* is the public
+ identifier. *system* is the system identifier.
+
+
+.. method:: XMLTreeBuilder.feed(data)
+
+ Feeds data to the parser. *data* is encoded data.
+
diff --git a/Doc/library/xml.etree.rst b/Doc/library/xml.etree.rst
new file mode 100644
index 0000000000..e14c5f9537
--- /dev/null
+++ b/Doc/library/xml.etree.rst
@@ -0,0 +1,25 @@
+:mod:`xml.etree` --- The ElementTree API for XML
+================================================
+
+.. module:: xml.etree
+ :synopsis: Package containing common ElementTree modules.
+.. moduleauthor:: Fredrik Lundh <fredrik@pythonware.com>
+
+
+.. versionadded:: 2.5
+
+The ElementTree package is a simple, efficient, and quite popular library for
+XML manipulation in Python. The :mod:`xml.etree` package contains the most
+common components from the ElementTree API library. In the current release,
+this package contains the :mod:`ElementTree`, :mod:`ElementPath`, and
+:mod:`ElementInclude` modules from the full ElementTree distribution.
+
+.. % XXX To be continued!
+
+
+.. seealso::
+
+ `ElementTree Overview <http://effbot.org/tag/elementtree>`_
+ The home page for :mod:`ElementTree`. This includes links to additional
+ documentation, alternative implementations, and other add-ons.
+
diff --git a/Doc/library/xml.sax.handler.rst b/Doc/library/xml.sax.handler.rst
new file mode 100644
index 0000000000..bc287d1337
--- /dev/null
+++ b/Doc/library/xml.sax.handler.rst
@@ -0,0 +1,402 @@
+
+:mod:`xml.sax.handler` --- Base classes for SAX handlers
+========================================================
+
+.. module:: xml.sax.handler
+ :synopsis: Base classes for SAX event handlers.
+.. moduleauthor:: Lars Marius Garshol <larsga@garshol.priv.no>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.0
+
+The SAX API defines four kinds of handlers: content handlers, DTD handlers,
+error handlers, and entity resolvers. Applications normally only need to
+implement those interfaces whose events they are interested in; they can
+implement the interfaces in a single object or in multiple objects. Handler
+implementations should inherit from the base classes provided in the module
+:mod:`xml.sax.handler`, so that all methods get default implementations.
+
+
+.. class:: ContentHandler
+
+ This is the main callback interface in SAX, and the one most important to
+ applications. The order of events in this interface mirrors the order of the
+ information in the document.
+
+
+.. class:: DTDHandler
+
+ Handle DTD events.
+
+ This interface specifies only those DTD events required for basic parsing
+ (unparsed entities and attributes).
+
+
+.. class:: EntityResolver
+
+ Basic interface for resolving entities. If you create an object implementing
+ this interface, then register the object with your Parser, the parser will call
+ the method in your object to resolve all external entities.
+
+
+.. class:: ErrorHandler
+
+ Interface used by the parser to present error and warning messages to the
+ application. The methods of this object control whether errors are immediately
+ converted to exceptions or are handled in some other way.
+
+In addition to these classes, :mod:`xml.sax.handler` provides symbolic constants
+for the feature and property names.
+
+
+.. data:: feature_namespaces
+
+ Value: ``"http://xml.org/sax/features/namespaces"`` --- true: Perform Namespace
+ processing. --- false: Optionally do not perform Namespace processing (implies
+ namespace-prefixes; default). --- access: (parsing) read-only; (not parsing)
+ read/write
+
+
+.. data:: feature_namespace_prefixes
+
+ Value: ``"http://xml.org/sax/features/namespace-prefixes"`` --- true: Report
+ the original prefixed names and attributes used for Namespace
+ declarations. --- false: Do not report attributes used for Namespace
+ declarations, and optionally do not report original prefixed names
+ (default). --- access: (parsing) read-only; (not parsing) read/write
+
+
+.. data:: feature_string_interning
+
+ Value: ``"http://xml.org/sax/features/string-interning"`` --- true: All element
+ names, prefixes, attribute names, Namespace URIs, and local names are interned
+ using the built-in intern function. --- false: Names are not necessarily
+ interned, although they may be (default). --- access: (parsing) read-only; (not
+ parsing) read/write
+
+
+.. data:: feature_validation
+
+ Value: ``"http://xml.org/sax/features/validation"`` --- true: Report all
+ validation errors (implies external-general-entities and
+ external-parameter-entities). --- false: Do not report validation errors. ---
+ access: (parsing) read-only; (not parsing) read/write
+
+
+.. data:: feature_external_ges
+
+ Value: ``"http://xml.org/sax/features/external-general-entities"`` --- true:
+ Include all external general (text) entities. --- false: Do not include
+ external general entities. --- access: (parsing) read-only; (not parsing)
+ read/write
+
+
+.. data:: feature_external_pes
+
+ Value: ``"http://xml.org/sax/features/external-parameter-entities"`` --- true:
+ Include all external parameter entities, including the external DTD subset. ---
+ false: Do not include any external parameter entities, even the external DTD
+ subset. --- access: (parsing) read-only; (not parsing) read/write
+
+
+.. data:: all_features
+
+ List of all features.
+
+
+.. data:: property_lexical_handler
+
+ Value: ``"http://xml.org/sax/properties/lexical-handler"`` --- data type:
+ xml.sax.sax2lib.LexicalHandler (not supported in Python 2) --- description: An
+ optional extension handler for lexical events like comments. --- access:
+ read/write
+
+
+.. data:: property_declaration_handler
+
+ Value: ``"http://xml.org/sax/properties/declaration-handler"`` --- data type:
+ xml.sax.sax2lib.DeclHandler (not supported in Python 2) --- description: An
+ optional extension handler for DTD-related events other than notations and
+ unparsed entities. --- access: read/write
+
+
+.. data:: property_dom_node
+
+ Value: ``"http://xml.org/sax/properties/dom-node"`` --- data type:
+ org.w3c.dom.Node (not supported in Python 2) --- description: When parsing,
+ the current DOM node being visited if this is a DOM iterator; when not parsing,
+ the root DOM node for iteration. --- access: (parsing) read-only; (not parsing)
+ read/write
+
+
+.. data:: property_xml_string
+
+ Value: ``"http://xml.org/sax/properties/xml-string"`` --- data type: String ---
+ description: The literal string of characters that was the source for the
+ current event. --- access: read-only
+
+
+.. data:: all_properties
+
+ List of all known property names.
+
+
+.. _content-handler-objects:
+
+ContentHandler Objects
+----------------------
+
+Users are expected to subclass :class:`ContentHandler` to support their
+application. The following methods are called by the parser on the appropriate
+events in the input document:
+
+
+.. method:: ContentHandler.setDocumentLocator(locator)
+
+ Called by the parser to give the application a locator for locating the origin
+ of document events.
+
+ SAX parsers are strongly encouraged (though not absolutely required) to supply a
+ locator: if it does so, it must supply the locator to the application by
+ invoking this method before invoking any of the other methods in the
+ DocumentHandler interface.
+
+ The locator allows the application to determine the end position of any
+ document-related event, even if the parser is not reporting an error. Typically,
+ the application will use this information for reporting its own errors (such as
+ character content that does not match an application's business rules). The
+ information returned by the locator is probably not sufficient for use with a
+ search engine.
+
+ Note that the locator will return correct information only during the invocation
+ of the events in this interface. The application should not attempt to use it at
+ any other time.
+
+
+.. method:: ContentHandler.startDocument()
+
+ Receive notification of the beginning of a document.
+
+ The SAX parser will invoke this method only once, before any other methods in
+ this interface or in DTDHandler (except for :meth:`setDocumentLocator`).
+
+
+.. method:: ContentHandler.endDocument()
+
+ Receive notification of the end of a document.
+
+ The SAX parser will invoke this method only once, and it will be the last method
+ invoked during the parse. The parser shall not invoke this method until it has
+ either abandoned parsing (because of an unrecoverable error) or reached the end
+ of input.
+
+
+.. method:: ContentHandler.startPrefixMapping(prefix, uri)
+
+ Begin the scope of a prefix-URI Namespace mapping.
+
+ The information from this event is not necessary for normal Namespace
+ processing: the SAX XML reader will automatically replace prefixes for element
+ and attribute names when the ``feature_namespaces`` feature is enabled (the
+ default).
+
+ There are cases, however, when applications need to use prefixes in character
+ data or in attribute values, where they cannot safely be expanded automatically;
+ the :meth:`startPrefixMapping` and :meth:`endPrefixMapping` events supply the
+ information to the application to expand prefixes in those contexts itself, if
+ necessary.
+
+ .. % XXX This is not really the default, is it? MvL
+
+ Note that :meth:`startPrefixMapping` and :meth:`endPrefixMapping` events are not
+ guaranteed to be properly nested relative to each-other: all
+ :meth:`startPrefixMapping` events will occur before the corresponding
+ :meth:`startElement` event, and all :meth:`endPrefixMapping` events will occur
+ after the corresponding :meth:`endElement` event, but their order is not
+ guaranteed.
+
+
+.. method:: ContentHandler.endPrefixMapping(prefix)
+
+ End the scope of a prefix-URI mapping.
+
+ See :meth:`startPrefixMapping` for details. This event will always occur after
+ the corresponding :meth:`endElement` event, but the order of
+ :meth:`endPrefixMapping` events is not otherwise guaranteed.
+
+
+.. method:: ContentHandler.startElement(name, attrs)
+
+ Signals the start of an element in non-namespace mode.
+
+ The *name* parameter contains the raw XML 1.0 name of the element type as a
+ string and the *attrs* parameter holds an object of the :class:`Attributes`
+ interface (see :ref:`attributes-objects`) containing the attributes of
+ the element. The object passed as *attrs* may be re-used by the parser; holding
+ on to a reference to it is not a reliable way to keep a copy of the attributes.
+ To keep a copy of the attributes, use the :meth:`copy` method of the *attrs*
+ object.
+
+
+.. method:: ContentHandler.endElement(name)
+
+ Signals the end of an element in non-namespace mode.
+
+ The *name* parameter contains the name of the element type, just as with the
+ :meth:`startElement` event.
+
+
+.. method:: ContentHandler.startElementNS(name, qname, attrs)
+
+ Signals the start of an element in namespace mode.
+
+ The *name* parameter contains the name of the element type as a ``(uri,
+ localname)`` tuple, the *qname* parameter contains the raw XML 1.0 name used in
+ the source document, and the *attrs* parameter holds an instance of the
+ :class:`AttributesNS` interface (see :ref:`attributes-ns-objects`)
+ containing the attributes of the element. If no namespace is associated with
+ the element, the *uri* component of *name* will be ``None``. The object passed
+ as *attrs* may be re-used by the parser; holding on to a reference to it is not
+ a reliable way to keep a copy of the attributes. To keep a copy of the
+ attributes, use the :meth:`copy` method of the *attrs* object.
+
+ Parsers may set the *qname* parameter to ``None``, unless the
+ ``feature_namespace_prefixes`` feature is activated.
+
+
+.. method:: ContentHandler.endElementNS(name, qname)
+
+ Signals the end of an element in namespace mode.
+
+ The *name* parameter contains the name of the element type, just as with the
+ :meth:`startElementNS` method, likewise the *qname* parameter.
+
+
+.. method:: ContentHandler.characters(content)
+
+ Receive notification of character data.
+
+ The Parser will call this method to report each chunk of character data. SAX
+ parsers may return all contiguous character data in a single chunk, or they may
+ split it into several chunks; however, all of the characters in any single event
+ must come from the same external entity so that the Locator provides useful
+ information.
+
+ *content* may be a Unicode string or a byte string; the ``expat`` reader module
+ produces always Unicode strings.
+
+ .. note::
+
+ The earlier SAX 1 interface provided by the Python XML Special Interest Group
+ used a more Java-like interface for this method. Since most parsers used from
+ Python did not take advantage of the older interface, the simpler signature was
+ chosen to replace it. To convert old code to the new interface, use *content*
+ instead of slicing content with the old *offset* and *length* parameters.
+
+
+.. method:: ContentHandler.ignorableWhitespace(whitespace)
+
+ Receive notification of ignorable whitespace in element content.
+
+ Validating Parsers must use this method to report each chunk of ignorable
+ whitespace (see the W3C XML 1.0 recommendation, section 2.10): non-validating
+ parsers may also use this method if they are capable of parsing and using
+ content models.
+
+ SAX parsers may return all contiguous whitespace in a single chunk, or they may
+ split it into several chunks; however, all of the characters in any single event
+ must come from the same external entity, so that the Locator provides useful
+ information.
+
+
+.. method:: ContentHandler.processingInstruction(target, data)
+
+ Receive notification of a processing instruction.
+
+ The Parser will invoke this method once for each processing instruction found:
+ note that processing instructions may occur before or after the main document
+ element.
+
+ A SAX parser should never report an XML declaration (XML 1.0, section 2.8) or a
+ text declaration (XML 1.0, section 4.3.1) using this method.
+
+
+.. method:: ContentHandler.skippedEntity(name)
+
+ Receive notification of a skipped entity.
+
+ The Parser will invoke this method once for each entity skipped. Non-validating
+ processors may skip entities if they have not seen the declarations (because,
+ for example, the entity was declared in an external DTD subset). All processors
+ may skip external entities, depending on the values of the
+ ``feature_external_ges`` and the ``feature_external_pes`` properties.
+
+
+.. _dtd-handler-objects:
+
+DTDHandler Objects
+------------------
+
+:class:`DTDHandler` instances provide the following methods:
+
+
+.. method:: DTDHandler.notationDecl(name, publicId, systemId)
+
+ Handle a notation declaration event.
+
+
+.. method:: DTDHandler.unparsedEntityDecl(name, publicId, systemId, ndata)
+
+ Handle an unparsed entity declaration event.
+
+
+.. _entity-resolver-objects:
+
+EntityResolver Objects
+----------------------
+
+
+.. method:: EntityResolver.resolveEntity(publicId, systemId)
+
+ Resolve the system identifier of an entity and return either the system
+ identifier to read from as a string, or an InputSource to read from. The default
+ implementation returns *systemId*.
+
+
+.. _sax-error-handler:
+
+ErrorHandler Objects
+--------------------
+
+Objects with this interface are used to receive error and warning information
+from the :class:`XMLReader`. If you create an object that implements this
+interface, then register the object with your :class:`XMLReader`, the parser
+will call the methods in your object to report all warnings and errors. There
+are three levels of errors available: warnings, (possibly) recoverable errors,
+and unrecoverable errors. All methods take a :exc:`SAXParseException` as the
+only parameter. Errors and warnings may be converted to an exception by raising
+the passed-in exception object.
+
+
+.. method:: ErrorHandler.error(exception)
+
+ Called when the parser encounters a recoverable error. If this method does not
+ raise an exception, parsing may continue, but further document information
+ should not be expected by the application. Allowing the parser to continue may
+ allow additional errors to be discovered in the input document.
+
+
+.. method:: ErrorHandler.fatalError(exception)
+
+ Called when the parser encounters an error it cannot recover from; parsing is
+ expected to terminate when this method returns.
+
+
+.. method:: ErrorHandler.warning(exception)
+
+ Called when the parser presents minor warning information to the application.
+ Parsing is expected to continue when this method returns, and document
+ information will continue to be passed to the application. Raising an exception
+ in this method will cause parsing to end.
+
diff --git a/Doc/library/xml.sax.reader.rst b/Doc/library/xml.sax.reader.rst
new file mode 100644
index 0000000000..d64a4fcc5a
--- /dev/null
+++ b/Doc/library/xml.sax.reader.rst
@@ -0,0 +1,386 @@
+
+:mod:`xml.sax.xmlreader` --- Interface for XML parsers
+======================================================
+
+.. module:: xml.sax.xmlreader
+ :synopsis: Interface which SAX-compliant XML parsers must implement.
+.. moduleauthor:: Lars Marius Garshol <larsga@garshol.priv.no>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.0
+
+SAX parsers implement the :class:`XMLReader` interface. They are implemented in
+a Python module, which must provide a function :func:`create_parser`. This
+function is invoked by :func:`xml.sax.make_parser` with no arguments to create
+a new parser object.
+
+
+.. class:: XMLReader()
+
+ Base class which can be inherited by SAX parsers.
+
+
+.. class:: IncrementalParser()
+
+ In some cases, it is desirable not to parse an input source at once, but to feed
+ chunks of the document as they get available. Note that the reader will normally
+ not read the entire file, but read it in chunks as well; still :meth:`parse`
+ won't return until the entire document is processed. So these interfaces should
+ be used if the blocking behaviour of :meth:`parse` is not desirable.
+
+ When the parser is instantiated it is ready to begin accepting data from the
+ feed method immediately. After parsing has been finished with a call to close
+ the reset method must be called to make the parser ready to accept new data,
+ either from feed or using the parse method.
+
+ Note that these methods must *not* be called during parsing, that is, after
+ parse has been called and before it returns.
+
+ By default, the class also implements the parse method of the XMLReader
+ interface using the feed, close and reset methods of the IncrementalParser
+ interface as a convenience to SAX 2.0 driver writers.
+
+
+.. class:: Locator()
+
+ Interface for associating a SAX event with a document location. A locator object
+ will return valid results only during calls to DocumentHandler methods; at any
+ other time, the results are unpredictable. If information is not available,
+ methods may return ``None``.
+
+
+.. class:: InputSource([systemId])
+
+ Encapsulation of the information needed by the :class:`XMLReader` to read
+ entities.
+
+ This class may include information about the public identifier, system
+ identifier, byte stream (possibly with character encoding information) and/or
+ the character stream of an entity.
+
+ Applications will create objects of this class for use in the
+ :meth:`XMLReader.parse` method and for returning from
+ EntityResolver.resolveEntity.
+
+ An :class:`InputSource` belongs to the application, the :class:`XMLReader` is
+ not allowed to modify :class:`InputSource` objects passed to it from the
+ application, although it may make copies and modify those.
+
+
+.. class:: AttributesImpl(attrs)
+
+ This is an implementation of the :class:`Attributes` interface (see section
+ :ref:`attributes-objects`). This is a dictionary-like object which
+ represents the element attributes in a :meth:`startElement` call. In addition
+ to the most useful dictionary operations, it supports a number of other
+ methods as described by the interface. Objects of this class should be
+ instantiated by readers; *attrs* must be a dictionary-like object containing
+ a mapping from attribute names to attribute values.
+
+
+.. class:: AttributesNSImpl(attrs, qnames)
+
+ Namespace-aware variant of :class:`AttributesImpl`, which will be passed to
+ :meth:`startElementNS`. It is derived from :class:`AttributesImpl`, but
+ understands attribute names as two-tuples of *namespaceURI* and
+ *localname*. In addition, it provides a number of methods expecting qualified
+ names as they appear in the original document. This class implements the
+ :class:`AttributesNS` interface (see section :ref:`attributes-ns-objects`).
+
+
+.. _xmlreader-objects:
+
+XMLReader Objects
+-----------------
+
+The :class:`XMLReader` interface supports the following methods:
+
+
+.. method:: XMLReader.parse(source)
+
+ Process an input source, producing SAX events. The *source* object can be a
+ system identifier (a string identifying the input source -- typically a file
+ name or an URL), a file-like object, or an :class:`InputSource` object. When
+ :meth:`parse` returns, the input is completely processed, and the parser object
+ can be discarded or reset. As a limitation, the current implementation only
+ accepts byte streams; processing of character streams is for further study.
+
+
+.. method:: XMLReader.getContentHandler()
+
+ Return the current :class:`ContentHandler`.
+
+
+.. method:: XMLReader.setContentHandler(handler)
+
+ Set the current :class:`ContentHandler`. If no :class:`ContentHandler` is set,
+ content events will be discarded.
+
+
+.. method:: XMLReader.getDTDHandler()
+
+ Return the current :class:`DTDHandler`.
+
+
+.. method:: XMLReader.setDTDHandler(handler)
+
+ Set the current :class:`DTDHandler`. If no :class:`DTDHandler` is set, DTD
+ events will be discarded.
+
+
+.. method:: XMLReader.getEntityResolver()
+
+ Return the current :class:`EntityResolver`.
+
+
+.. method:: XMLReader.setEntityResolver(handler)
+
+ Set the current :class:`EntityResolver`. If no :class:`EntityResolver` is set,
+ attempts to resolve an external entity will result in opening the system
+ identifier for the entity, and fail if it is not available.
+
+
+.. method:: XMLReader.getErrorHandler()
+
+ Return the current :class:`ErrorHandler`.
+
+
+.. method:: XMLReader.setErrorHandler(handler)
+
+ Set the current error handler. If no :class:`ErrorHandler` is set, errors will
+ be raised as exceptions, and warnings will be printed.
+
+
+.. method:: XMLReader.setLocale(locale)
+
+ Allow an application to set the locale for errors and warnings.
+
+ SAX parsers are not required to provide localization for errors and warnings; if
+ they cannot support the requested locale, however, they must throw a SAX
+ exception. Applications may request a locale change in the middle of a parse.
+
+
+.. method:: XMLReader.getFeature(featurename)
+
+ Return the current setting for feature *featurename*. If the feature is not
+ recognized, :exc:`SAXNotRecognizedException` is raised. The well-known
+ featurenames are listed in the module :mod:`xml.sax.handler`.
+
+
+.. method:: XMLReader.setFeature(featurename, value)
+
+ Set the *featurename* to *value*. If the feature is not recognized,
+ :exc:`SAXNotRecognizedException` is raised. If the feature or its setting is not
+ supported by the parser, *SAXNotSupportedException* is raised.
+
+
+.. method:: XMLReader.getProperty(propertyname)
+
+ Return the current setting for property *propertyname*. If the property is not
+ recognized, a :exc:`SAXNotRecognizedException` is raised. The well-known
+ propertynames are listed in the module :mod:`xml.sax.handler`.
+
+
+.. method:: XMLReader.setProperty(propertyname, value)
+
+ Set the *propertyname* to *value*. If the property is not recognized,
+ :exc:`SAXNotRecognizedException` is raised. If the property or its setting is
+ not supported by the parser, *SAXNotSupportedException* is raised.
+
+
+.. _incremental-parser-objects:
+
+IncrementalParser Objects
+-------------------------
+
+Instances of :class:`IncrementalParser` offer the following additional methods:
+
+
+.. method:: IncrementalParser.feed(data)
+
+ Process a chunk of *data*.
+
+
+.. method:: IncrementalParser.close()
+
+ Assume the end of the document. That will check well-formedness conditions that
+ can be checked only at the end, invoke handlers, and may clean up resources
+ allocated during parsing.
+
+
+.. method:: IncrementalParser.reset()
+
+ This method is called after close has been called to reset the parser so that it
+ is ready to parse new documents. The results of calling parse or feed after
+ close without calling reset are undefined.
+
+
+.. _locator-objects:
+
+Locator Objects
+---------------
+
+Instances of :class:`Locator` provide these methods:
+
+
+.. method:: Locator.getColumnNumber()
+
+ Return the column number where the current event ends.
+
+
+.. method:: Locator.getLineNumber()
+
+ Return the line number where the current event ends.
+
+
+.. method:: Locator.getPublicId()
+
+ Return the public identifier for the current event.
+
+
+.. method:: Locator.getSystemId()
+
+ Return the system identifier for the current event.
+
+
+.. _input-source-objects:
+
+InputSource Objects
+-------------------
+
+
+.. method:: InputSource.setPublicId(id)
+
+ Sets the public identifier of this :class:`InputSource`.
+
+
+.. method:: InputSource.getPublicId()
+
+ Returns the public identifier of this :class:`InputSource`.
+
+
+.. method:: InputSource.setSystemId(id)
+
+ Sets the system identifier of this :class:`InputSource`.
+
+
+.. method:: InputSource.getSystemId()
+
+ Returns the system identifier of this :class:`InputSource`.
+
+
+.. method:: InputSource.setEncoding(encoding)
+
+ Sets the character encoding of this :class:`InputSource`.
+
+ The encoding must be a string acceptable for an XML encoding declaration (see
+ section 4.3.3 of the XML recommendation).
+
+ The encoding attribute of the :class:`InputSource` is ignored if the
+ :class:`InputSource` also contains a character stream.
+
+
+.. method:: InputSource.getEncoding()
+
+ Get the character encoding of this InputSource.
+
+
+.. method:: InputSource.setByteStream(bytefile)
+
+ Set the byte stream (a Python file-like object which does not perform
+ byte-to-character conversion) for this input source.
+
+ The SAX parser will ignore this if there is also a character stream specified,
+ but it will use a byte stream in preference to opening a URI connection itself.
+
+ If the application knows the character encoding of the byte stream, it should
+ set it with the setEncoding method.
+
+
+.. method:: InputSource.getByteStream()
+
+ Get the byte stream for this input source.
+
+ The getEncoding method will return the character encoding for this byte stream,
+ or None if unknown.
+
+
+.. method:: InputSource.setCharacterStream(charfile)
+
+ Set the character stream for this input source. (The stream must be a Python 1.6
+ Unicode-wrapped file-like that performs conversion to Unicode strings.)
+
+ If there is a character stream specified, the SAX parser will ignore any byte
+ stream and will not attempt to open a URI connection to the system identifier.
+
+
+.. method:: InputSource.getCharacterStream()
+
+ Get the character stream for this input source.
+
+
+.. _attributes-objects:
+
+The :class:`Attributes` Interface
+---------------------------------
+
+:class:`Attributes` objects implement a portion of the mapping protocol,
+including the methods :meth:`copy`, :meth:`get`, :meth:`has_key`, :meth:`items`,
+:meth:`keys`, and :meth:`values`. The following methods are also provided:
+
+
+.. method:: Attributes.getLength()
+
+ Return the number of attributes.
+
+
+.. method:: Attributes.getNames()
+
+ Return the names of the attributes.
+
+
+.. method:: Attributes.getType(name)
+
+ Returns the type of the attribute *name*, which is normally ``'CDATA'``.
+
+
+.. method:: Attributes.getValue(name)
+
+ Return the value of attribute *name*.
+
+.. % getValueByQName, getNameByQName, getQNameByName, getQNames available
+.. % here already, but documented only for derived class.
+
+
+.. _attributes-ns-objects:
+
+The :class:`AttributesNS` Interface
+-----------------------------------
+
+This interface is a subtype of the :class:`Attributes` interface (see section
+:ref:`attributes-objects`). All methods supported by that interface are also
+available on :class:`AttributesNS` objects.
+
+The following methods are also available:
+
+
+.. method:: AttributesNS.getValueByQName(name)
+
+ Return the value for a qualified name.
+
+
+.. method:: AttributesNS.getNameByQName(name)
+
+ Return the ``(namespace, localname)`` pair for a qualified *name*.
+
+
+.. method:: AttributesNS.getQNameByName(name)
+
+ Return the qualified name for a ``(namespace, localname)`` pair.
+
+
+.. method:: AttributesNS.getQNames()
+
+ Return the qualified names of all attributes.
+
diff --git a/Doc/library/xml.sax.rst b/Doc/library/xml.sax.rst
new file mode 100644
index 0000000000..43d17c2aed
--- /dev/null
+++ b/Doc/library/xml.sax.rst
@@ -0,0 +1,143 @@
+
+:mod:`xml.sax` --- Support for SAX2 parsers
+===========================================
+
+.. module:: xml.sax
+ :synopsis: Package containing SAX2 base classes and convenience functions.
+.. moduleauthor:: Lars Marius Garshol <larsga@garshol.priv.no>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.0
+
+The :mod:`xml.sax` package provides a number of modules which implement the
+Simple API for XML (SAX) interface for Python. The package itself provides the
+SAX exceptions and the convenience functions which will be most used by users of
+the SAX API.
+
+The convenience functions are:
+
+
+.. function:: make_parser([parser_list])
+
+ Create and return a SAX :class:`XMLReader` object. The first parser found will
+ be used. If *parser_list* is provided, it must be a sequence of strings which
+ name modules that have a function named :func:`create_parser`. Modules listed
+ in *parser_list* will be used before modules in the default list of parsers.
+
+
+.. function:: parse(filename_or_stream, handler[, error_handler])
+
+ Create a SAX parser and use it to parse a document. The document, passed in as
+ *filename_or_stream*, can be a filename or a file object. The *handler*
+ parameter needs to be a SAX :class:`ContentHandler` instance. If
+ *error_handler* is given, it must be a SAX :class:`ErrorHandler` instance; if
+ omitted, :exc:`SAXParseException` will be raised on all errors. There is no
+ return value; all work must be done by the *handler* passed in.
+
+
+.. function:: parseString(string, handler[, error_handler])
+
+ Similar to :func:`parse`, but parses from a buffer *string* received as a
+ parameter.
+
+A typical SAX application uses three kinds of objects: readers, handlers and
+input sources. "Reader" in this context is another term for parser, i.e. some
+piece of code that reads the bytes or characters from the input source, and
+produces a sequence of events. The events then get distributed to the handler
+objects, i.e. the reader invokes a method on the handler. A SAX application
+must therefore obtain a reader object, create or open the input sources, create
+the handlers, and connect these objects all together. As the final step of
+preparation, the reader is called to parse the input. During parsing, methods on
+the handler objects are called based on structural and syntactic events from the
+input data.
+
+For these objects, only the interfaces are relevant; they are normally not
+instantiated by the application itself. Since Python does not have an explicit
+notion of interface, they are formally introduced as classes, but applications
+may use implementations which do not inherit from the provided classes. The
+:class:`InputSource`, :class:`Locator`, :class:`Attributes`,
+:class:`AttributesNS`, and :class:`XMLReader` interfaces are defined in the
+module :mod:`xml.sax.xmlreader`. The handler interfaces are defined in
+:mod:`xml.sax.handler`. For convenience, :class:`InputSource` (which is often
+instantiated directly) and the handler classes are also available from
+:mod:`xml.sax`. These interfaces are described below.
+
+In addition to these classes, :mod:`xml.sax` provides the following exception
+classes.
+
+
+.. exception:: SAXException(msg[, exception])
+
+ Encapsulate an XML error or warning. This class can contain basic error or
+ warning information from either the XML parser or the application: it can be
+ subclassed to provide additional functionality or to add localization. Note
+ that although the handlers defined in the :class:`ErrorHandler` interface
+ receive instances of this exception, it is not required to actually raise the
+ exception --- it is also useful as a container for information.
+
+ When instantiated, *msg* should be a human-readable description of the error.
+ The optional *exception* parameter, if given, should be ``None`` or an exception
+ that was caught by the parsing code and is being passed along as information.
+
+ This is the base class for the other SAX exception classes.
+
+
+.. exception:: SAXParseException(msg, exception, locator)
+
+ Subclass of :exc:`SAXException` raised on parse errors. Instances of this class
+ are passed to the methods of the SAX :class:`ErrorHandler` interface to provide
+ information about the parse error. This class supports the SAX :class:`Locator`
+ interface as well as the :class:`SAXException` interface.
+
+
+.. exception:: SAXNotRecognizedException(msg[, exception])
+
+ Subclass of :exc:`SAXException` raised when a SAX :class:`XMLReader` is
+ confronted with an unrecognized feature or property. SAX applications and
+ extensions may use this class for similar purposes.
+
+
+.. exception:: SAXNotSupportedException(msg[, exception])
+
+ Subclass of :exc:`SAXException` raised when a SAX :class:`XMLReader` is asked to
+ enable a feature that is not supported, or to set a property to a value that the
+ implementation does not support. SAX applications and extensions may use this
+ class for similar purposes.
+
+
+.. seealso::
+
+ `SAX: The Simple API for XML <http://www.saxproject.org/>`_
+ This site is the focal point for the definition of the SAX API. It provides a
+ Java implementation and online documentation. Links to implementations and
+ historical information are also available.
+
+ Module :mod:`xml.sax.handler`
+ Definitions of the interfaces for application-provided objects.
+
+ Module :mod:`xml.sax.saxutils`
+ Convenience functions for use in SAX applications.
+
+ Module :mod:`xml.sax.xmlreader`
+ Definitions of the interfaces for parser-provided objects.
+
+
+.. _sax-exception-objects:
+
+SAXException Objects
+--------------------
+
+The :class:`SAXException` exception class supports the following methods:
+
+
+.. method:: SAXException.getMessage()
+
+ Return a human-readable message describing the error condition.
+
+
+.. method:: SAXException.getException()
+
+ Return an encapsulated exception object, or ``None``.
+
diff --git a/Doc/library/xml.sax.utils.rst b/Doc/library/xml.sax.utils.rst
new file mode 100644
index 0000000000..0585a9bfe1
--- /dev/null
+++ b/Doc/library/xml.sax.utils.rst
@@ -0,0 +1,83 @@
+
+:mod:`xml.sax.saxutils` --- SAX Utilities
+=========================================
+
+.. module:: xml.sax.saxutils
+ :synopsis: Convenience functions and classes for use with SAX.
+.. moduleauthor:: Lars Marius Garshol <larsga@garshol.priv.no>
+.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
+
+
+.. versionadded:: 2.0
+
+The module :mod:`xml.sax.saxutils` contains a number of classes and functions
+that are commonly useful when creating SAX applications, either in direct use,
+or as base classes.
+
+
+.. function:: escape(data[, entities])
+
+ Escape ``'&'``, ``'<'``, and ``'>'`` in a string of data.
+
+ You can escape other strings of data by passing a dictionary as the optional
+ *entities* parameter. The keys and values must all be strings; each key will be
+ replaced with its corresponding value.
+
+
+.. function:: unescape(data[, entities])
+
+ Unescape ``'&amp;'``, ``'&lt;'``, and ``'&gt;'`` in a string of data.
+
+ You can unescape other strings of data by passing a dictionary as the optional
+ *entities* parameter. The keys and values must all be strings; each key will be
+ replaced with its corresponding value.
+
+ .. versionadded:: 2.3
+
+
+.. function:: quoteattr(data[, entities])
+
+ Similar to :func:`escape`, but also prepares *data* to be used as an
+ attribute value. The return value is a quoted version of *data* with any
+ additional required replacements. :func:`quoteattr` will select a quote
+ character based on the content of *data*, attempting to avoid encoding any
+ quote characters in the string. If both single- and double-quote characters
+ are already in *data*, the double-quote characters will be encoded and *data*
+ will be wrapped in double-quotes. The resulting string can be used directly
+ as an attribute value::
+
+ >>> print "<element attr=%s>" % quoteattr("ab ' cd \" ef")
+ <element attr="ab ' cd &quot; ef">
+
+ This function is useful when generating attribute values for HTML or any SGML
+ using the reference concrete syntax.
+
+ .. versionadded:: 2.2
+
+
+.. class:: XMLGenerator([out[, encoding]])
+
+ This class implements the :class:`ContentHandler` interface by writing SAX
+ events back into an XML document. In other words, using an :class:`XMLGenerator`
+ as the content handler will reproduce the original document being parsed. *out*
+ should be a file-like object which will default to *sys.stdout*. *encoding* is
+ the encoding of the output stream which defaults to ``'iso-8859-1'``.
+
+
+.. class:: XMLFilterBase(base)
+
+ This class is designed to sit between an :class:`XMLReader` and the client
+ application's event handlers. By default, it does nothing but pass requests up
+ to the reader and events on to the handlers unmodified, but subclasses can
+ override specific methods to modify the event stream or the configuration
+ requests as they pass through.
+
+
+.. function:: prepare_input_source(source[, base])
+
+ This function takes an input source and an optional base URL and returns a fully
+ resolved :class:`InputSource` object ready for reading. The input source can be
+ given as a string, a file-like object, or an :class:`InputSource` object;
+ parsers will use this function to implement the polymorphic *source* argument to
+ their :meth:`parse` method.
+
diff --git a/Doc/library/xmlrpclib.rst b/Doc/library/xmlrpclib.rst
new file mode 100644
index 0000000000..cd507c46e4
--- /dev/null
+++ b/Doc/library/xmlrpclib.rst
@@ -0,0 +1,422 @@
+
+:mod:`xmlrpclib` --- XML-RPC client access
+==========================================
+
+.. module:: xmlrpclib
+ :synopsis: XML-RPC client access.
+.. moduleauthor:: Fredrik Lundh <fredrik@pythonware.com>
+.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
+
+
+.. % Not everything is documented yet. It might be good to describe
+.. % Marshaller, Unmarshaller, getparser, dumps, loads, and Transport.
+
+.. versionadded:: 2.2
+
+XML-RPC is a Remote Procedure Call method that uses XML passed via HTTP as a
+transport. With it, a client can call methods with parameters on a remote
+server (the server is named by a URI) and get back structured data. This module
+supports writing XML-RPC client code; it handles all the details of translating
+between conformable Python objects and XML on the wire.
+
+
+.. class:: ServerProxy(uri[, transport[, encoding[, verbose[, allow_none[, use_datetime]]]]])
+
+ A :class:`ServerProxy` instance is an object that manages communication with a
+ remote XML-RPC server. The required first argument is a URI (Uniform Resource
+ Indicator), and will normally be the URL of the server. The optional second
+ argument is a transport factory instance; by default it is an internal
+ :class:`SafeTransport` instance for https: URLs and an internal HTTP
+ :class:`Transport` instance otherwise. The optional third argument is an
+ encoding, by default UTF-8. The optional fourth argument is a debugging flag.
+ If *allow_none* is true, the Python constant ``None`` will be translated into
+ XML; the default behaviour is for ``None`` to raise a :exc:`TypeError`. This is
+ a commonly-used extension to the XML-RPC specification, but isn't supported by
+ all clients and servers; see http://ontosys.com/xml-rpc/extensions.php for a
+ description. The *use_datetime* flag can be used to cause date/time values to
+ be presented as :class:`datetime.datetime` objects; this is false by default.
+ :class:`datetime.datetime`, :class:`datetime.date` and :class:`datetime.time`
+ objects may be passed to calls. :class:`datetime.date` objects are converted
+ with a time of "00:00:00". :class:`datetime.time` objects are converted using
+ today's date.
+
+ Both the HTTP and HTTPS transports support the URL syntax extension for HTTP
+ Basic Authentication: ``http://user:pass@host:port/path``. The ``user:pass``
+ portion will be base64-encoded as an HTTP 'Authorization' header, and sent to
+ the remote server as part of the connection process when invoking an XML-RPC
+ method. You only need to use this if the remote server requires a Basic
+ Authentication user and password.
+
+ The returned instance is a proxy object with methods that can be used to invoke
+ corresponding RPC calls on the remote server. If the remote server supports the
+ introspection API, the proxy can also be used to query the remote server for the
+ methods it supports (service discovery) and fetch other server-associated
+ metadata.
+
+ :class:`ServerProxy` instance methods take Python basic types and objects as
+ arguments and return Python basic types and classes. Types that are conformable
+ (e.g. that can be marshalled through XML), include the following (and except
+ where noted, they are unmarshalled as the same Python type):
+
+ +---------------------------------+---------------------------------------------+
+ | Name | Meaning |
+ +=================================+=============================================+
+ | :const:`boolean` | The :const:`True` and :const:`False` |
+ | | constants |
+ +---------------------------------+---------------------------------------------+
+ | :const:`integers` | Pass in directly |
+ +---------------------------------+---------------------------------------------+
+ | :const:`floating-point numbers` | Pass in directly |
+ +---------------------------------+---------------------------------------------+
+ | :const:`strings` | Pass in directly |
+ +---------------------------------+---------------------------------------------+
+ | :const:`arrays` | Any Python sequence type containing |
+ | | conformable elements. Arrays are returned |
+ | | as lists |
+ +---------------------------------+---------------------------------------------+
+ | :const:`structures` | A Python dictionary. Keys must be strings, |
+ | | values may be any conformable type. Objects |
+ | | of user-defined classes can be passed in; |
+ | | only their *__dict__* attribute is |
+ | | transmitted. |
+ +---------------------------------+---------------------------------------------+
+ | :const:`dates` | in seconds since the epoch (pass in an |
+ | | instance of the :class:`DateTime` class) or |
+ | | a :class:`datetime.datetime`, |
+ | | :class:`datetime.date` or |
+ | | :class:`datetime.time` instance |
+ +---------------------------------+---------------------------------------------+
+ | :const:`binary data` | pass in an instance of the :class:`Binary` |
+ | | wrapper class |
+ +---------------------------------+---------------------------------------------+
+
+ This is the full set of data types supported by XML-RPC. Method calls may also
+ raise a special :exc:`Fault` instance, used to signal XML-RPC server errors, or
+ :exc:`ProtocolError` used to signal an error in the HTTP/HTTPS transport layer.
+ Both :exc:`Fault` and :exc:`ProtocolError` derive from a base class called
+ :exc:`Error`. Note that even though starting with Python 2.2 you can subclass
+ builtin types, the xmlrpclib module currently does not marshal instances of such
+ subclasses.
+
+ When passing strings, characters special to XML such as ``<``, ``>``, and ``&``
+ will be automatically escaped. However, it's the caller's responsibility to
+ ensure that the string is free of characters that aren't allowed in XML, such as
+ the control characters with ASCII values between 0 and 31 (except, of course,
+ tab, newline and carriage return); failing to do this will result in an XML-RPC
+ request that isn't well-formed XML. If you have to pass arbitrary strings via
+ XML-RPC, use the :class:`Binary` wrapper class described below.
+
+ :class:`Server` is retained as an alias for :class:`ServerProxy` for backwards
+ compatibility. New code should use :class:`ServerProxy`.
+
+ .. versionchanged:: 2.5
+ The *use_datetime* flag was added.
+
+ .. versionchanged:: 2.6
+ Instances of new-style classes can be passed in if they have an *__dict__*
+ attribute and don't have a base class that is marshalled in a special way.
+
+
+.. seealso::
+
+ `XML-RPC HOWTO <http://www.tldp.org/HOWTO/XML-RPC-HOWTO/index.html>`_
+ A good description of XML operation and client software in several languages.
+ Contains pretty much everything an XML-RPC client developer needs to know.
+
+ `XML-RPC Hacks page <http://xmlrpc-c.sourceforge.net/hacks.php>`_
+ Extensions for various open-source libraries to support introspection and
+ multicall.
+
+
+.. _serverproxy-objects:
+
+ServerProxy Objects
+-------------------
+
+A :class:`ServerProxy` instance has a method corresponding to each remote
+procedure call accepted by the XML-RPC server. Calling the method performs an
+RPC, dispatched by both name and argument signature (e.g. the same method name
+can be overloaded with multiple argument signatures). The RPC finishes by
+returning a value, which may be either returned data in a conformant type or a
+:class:`Fault` or :class:`ProtocolError` object indicating an error.
+
+Servers that support the XML introspection API support some common methods
+grouped under the reserved :attr:`system` member:
+
+
+.. method:: ServerProxy.system.listMethods()
+
+ This method returns a list of strings, one for each (non-system) method
+ supported by the XML-RPC server.
+
+
+.. method:: ServerProxy.system.methodSignature(name)
+
+ This method takes one parameter, the name of a method implemented by the XML-RPC
+ server.It returns an array of possible signatures for this method. A signature
+ is an array of types. The first of these types is the return type of the method,
+ the rest are parameters.
+
+ Because multiple signatures (ie. overloading) is permitted, this method returns
+ a list of signatures rather than a singleton.
+
+ Signatures themselves are restricted to the top level parameters expected by a
+ method. For instance if a method expects one array of structs as a parameter,
+ and it returns a string, its signature is simply "string, array". If it expects
+ three integers and returns a string, its signature is "string, int, int, int".
+
+ If no signature is defined for the method, a non-array value is returned. In
+ Python this means that the type of the returned value will be something other
+ that list.
+
+
+.. method:: ServerProxy.system.methodHelp(name)
+
+ This method takes one parameter, the name of a method implemented by the XML-RPC
+ server. It returns a documentation string describing the use of that method. If
+ no such string is available, an empty string is returned. The documentation
+ string may contain HTML markup.
+
+Introspection methods are currently supported by servers written in PHP, C and
+Microsoft .NET. Partial introspection support is included in recent updates to
+UserLand Frontier. Introspection support for Perl, Python and Java is available
+at the `XML-RPC Hacks <http://xmlrpc-c.sourceforge.net/hacks.php>`_ page.
+
+
+.. _boolean-objects:
+
+Boolean Objects
+---------------
+
+This class may be initialized from any Python value; the instance returned
+depends only on its truth value. It supports various Python operators through
+:meth:`__cmp__`, :meth:`__repr__`, :meth:`__int__`, and :meth:`__bool__`
+methods, all implemented in the obvious ways.
+
+It also has the following method, supported mainly for internal use by the
+unmarshalling code:
+
+
+.. method:: Boolean.encode(out)
+
+ Write the XML-RPC encoding of this Boolean item to the out stream object.
+
+
+.. _datetime-objects:
+
+DateTime Objects
+----------------
+
+This class may be initialized with seconds since the epoch, a time tuple, an ISO
+8601 time/date string, or a :class:`datetime.datetime`, :class:`datetime.date`
+or :class:`datetime.time` instance. It has the following methods, supported
+mainly for internal use by the marshalling/unmarshalling code:
+
+
+.. method:: DateTime.decode(string)
+
+ Accept a string as the instance's new time value.
+
+
+.. method:: DateTime.encode(out)
+
+ Write the XML-RPC encoding of this :class:`DateTime` item to the *out* stream
+ object.
+
+It also supports certain of Python's built-in operators through :meth:`__cmp__`
+and :meth:`__repr__` methods.
+
+
+.. _binary-objects:
+
+Binary Objects
+--------------
+
+This class may be initialized from string data (which may include NULs). The
+primary access to the content of a :class:`Binary` object is provided by an
+attribute:
+
+
+.. attribute:: Binary.data
+
+ The binary data encapsulated by the :class:`Binary` instance. The data is
+ provided as an 8-bit string.
+
+:class:`Binary` objects have the following methods, supported mainly for
+internal use by the marshalling/unmarshalling code:
+
+
+.. method:: Binary.decode(string)
+
+ Accept a base64 string and decode it as the instance's new data.
+
+
+.. method:: Binary.encode(out)
+
+ Write the XML-RPC base 64 encoding of this binary item to the out stream object.
+
+It also supports certain of Python's built-in operators through a
+:meth:`__cmp__` method.
+
+
+.. _fault-objects:
+
+Fault Objects
+-------------
+
+A :class:`Fault` object encapsulates the content of an XML-RPC fault tag. Fault
+objects have the following members:
+
+
+.. attribute:: Fault.faultCode
+
+ A string indicating the fault type.
+
+
+.. attribute:: Fault.faultString
+
+ A string containing a diagnostic message associated with the fault.
+
+
+.. _protocol-error-objects:
+
+ProtocolError Objects
+---------------------
+
+A :class:`ProtocolError` object describes a protocol error in the underlying
+transport layer (such as a 404 'not found' error if the server named by the URI
+does not exist). It has the following members:
+
+
+.. attribute:: ProtocolError.url
+
+ The URI or URL that triggered the error.
+
+
+.. attribute:: ProtocolError.errcode
+
+ The error code.
+
+
+.. attribute:: ProtocolError.errmsg
+
+ The error message or diagnostic string.
+
+
+.. attribute:: ProtocolError.headers
+
+ A string containing the headers of the HTTP/HTTPS request that triggered the
+ error.
+
+
+MultiCall Objects
+-----------------
+
+.. versionadded:: 2.4
+
+In http://www.xmlrpc.com/discuss/msgReader%241208, an approach is presented to
+encapsulate multiple calls to a remote server into a single request.
+
+
+.. class:: MultiCall(server)
+
+ Create an object used to boxcar method calls. *server* is the eventual target of
+ the call. Calls can be made to the result object, but they will immediately
+ return ``None``, and only store the call name and parameters in the
+ :class:`MultiCall` object. Calling the object itself causes all stored calls to
+ be transmitted as a single ``system.multicall`` request. The result of this call
+ is a generator; iterating over this generator yields the individual results.
+
+A usage example of this class is ::
+
+ multicall = MultiCall(server_proxy)
+ multicall.add(2,3)
+ multicall.get_address("Guido")
+ add_result, address = multicall()
+
+
+Convenience Functions
+---------------------
+
+
+.. function:: boolean(value)
+
+ Convert any Python value to one of the XML-RPC Boolean constants, ``True`` or
+ ``False``.
+
+
+.. function:: dumps(params[, methodname[, methodresponse[, encoding[, allow_none]]]])
+
+ Convert *params* into an XML-RPC request. or into a response if *methodresponse*
+ is true. *params* can be either a tuple of arguments or an instance of the
+ :exc:`Fault` exception class. If *methodresponse* is true, only a single value
+ can be returned, meaning that *params* must be of length 1. *encoding*, if
+ supplied, is the encoding to use in the generated XML; the default is UTF-8.
+ Python's :const:`None` value cannot be used in standard XML-RPC; to allow using
+ it via an extension, provide a true value for *allow_none*.
+
+
+.. function:: loads(data[, use_datetime])
+
+ Convert an XML-RPC request or response into Python objects, a ``(params,
+ methodname)``. *params* is a tuple of argument; *methodname* is a string, or
+ ``None`` if no method name is present in the packet. If the XML-RPC packet
+ represents a fault condition, this function will raise a :exc:`Fault` exception.
+ The *use_datetime* flag can be used to cause date/time values to be presented as
+ :class:`datetime.datetime` objects; this is false by default. Note that even if
+ you call an XML-RPC method with :class:`datetime.date` or :class:`datetime.time`
+ objects, they are converted to :class:`DateTime` objects internally, so only
+ :class:`datetime.datetime` objects will be returned.
+
+ .. versionchanged:: 2.5
+ The *use_datetime* flag was added.
+
+
+.. _xmlrpc-client-example:
+
+Example of Client Usage
+-----------------------
+
+::
+
+ # simple test program (from the XML-RPC specification)
+ from xmlrpclib import ServerProxy, Error
+
+ # server = ServerProxy("http://localhost:8000") # local server
+ server = ServerProxy("http://betty.userland.com")
+
+ print server
+
+ try:
+ print server.examples.getStateName(41)
+ except Error as v:
+ print "ERROR", v
+
+To access an XML-RPC server through a proxy, you need to define a custom
+transport. The following example, written by NoboNobo, shows how:
+
+.. % fill in original author's name if we ever learn it
+
+.. % Example taken from http://lowlife.jp/nobonobo/wiki/xmlrpcwithproxy.html
+
+::
+
+ import xmlrpclib, httplib
+
+ class ProxiedTransport(xmlrpclib.Transport):
+ def set_proxy(self, proxy):
+ self.proxy = proxy
+ def make_connection(self, host):
+ self.realhost = host
+ h = httplib.HTTP(self.proxy)
+ return h
+ def send_request(self, connection, handler, request_body):
+ connection.putrequest("POST", 'http://%s%s' % (self.realhost, handler))
+ def send_host(self, connection, host):
+ connection.putheader('Host', self.realhost)
+
+ p = ProxiedTransport()
+ p.set_proxy('proxy-server:8080')
+ server = xmlrpclib.Server('http://time.xmlrpc.com/RPC2', transport=p)
+ print server.currentTime.getCurrentTime()
+
diff --git a/Doc/library/zipfile.rst b/Doc/library/zipfile.rst
new file mode 100644
index 0000000000..5e51bfc854
--- /dev/null
+++ b/Doc/library/zipfile.rst
@@ -0,0 +1,408 @@
+
+:mod:`zipfile` --- Work with ZIP archives
+=========================================
+
+.. module:: zipfile
+ :synopsis: Read and write ZIP-format archive files.
+.. moduleauthor:: James C. Ahlstrom <jim@interet.com>
+.. sectionauthor:: James C. Ahlstrom <jim@interet.com>
+
+
+.. % LaTeX markup by Fred L. Drake, Jr. <fdrake@acm.org>
+
+.. versionadded:: 1.6
+
+The ZIP file format is a common archive and compression standard. This module
+provides tools to create, read, write, append, and list a ZIP file. Any
+advanced use of this module will require an understanding of the format, as
+defined in `PKZIP Application Note
+<http://www.pkware.com/business_and_developers/developer/appnote/>`_.
+
+This module does not currently handle ZIP files which have appended comments, or
+multi-disk ZIP files. It can handle ZIP files that use the ZIP64 extensions
+(that is ZIP files that are more than 4 GByte in size). It supports decryption
+of encrypted files in ZIP archives, but it cannot currently create an encrypted
+file.
+
+The available attributes of this module are:
+
+
+.. exception:: BadZipfile
+
+ The error raised for bad ZIP files (old name: ``zipfile.error``).
+
+
+.. exception:: LargeZipFile
+
+ The error raised when a ZIP file would require ZIP64 functionality but that has
+ not been enabled.
+
+
+.. class:: ZipFile
+
+ The class for reading and writing ZIP files. See section
+ :ref:`zipfile-objects` for constructor details.
+
+
+.. class:: PyZipFile
+
+ Class for creating ZIP archives containing Python libraries.
+
+
+.. class:: ZipInfo([filename[, date_time]])
+
+ Class used to represent information about a member of an archive. Instances
+ of this class are returned by the :meth:`getinfo` and :meth:`infolist`
+ methods of :class:`ZipFile` objects. Most users of the :mod:`zipfile` module
+ will not need to create these, but only use those created by this
+ module. *filename* should be the full name of the archive member, and
+ *date_time* should be a tuple containing six fields which describe the time
+ of the last modification to the file; the fields are described in section
+ :ref:`zipinfo-objects`.
+
+
+.. function:: is_zipfile(filename)
+
+ Returns ``True`` if *filename* is a valid ZIP file based on its magic number,
+ otherwise returns ``False``. This module does not currently handle ZIP files
+ which have appended comments.
+
+
+.. data:: ZIP_STORED
+
+ The numeric constant for an uncompressed archive member.
+
+
+.. data:: ZIP_DEFLATED
+
+ The numeric constant for the usual ZIP compression method. This requires the
+ zlib module. No other compression methods are currently supported.
+
+
+.. seealso::
+
+ `PKZIP Application Note <http://www.pkware.com/business_and_developers/developer/appnote/>`_
+ Documentation on the ZIP file format by Phil Katz, the creator of the format and
+ algorithms used.
+
+ `Info-ZIP Home Page <http://www.info-zip.org/>`_
+ Information about the Info-ZIP project's ZIP archive programs and development
+ libraries.
+
+
+.. _zipfile-objects:
+
+ZipFile Objects
+---------------
+
+
+.. class:: ZipFile(file[, mode[, compression[, allowZip64]]])
+
+ Open a ZIP file, where *file* can be either a path to a file (a string) or a
+ file-like object. The *mode* parameter should be ``'r'`` to read an existing
+ file, ``'w'`` to truncate and write a new file, or ``'a'`` to append to an
+ existing file. If *mode* is ``'a'`` and *file* refers to an existing ZIP file,
+ then additional files are added to it. If *file* does not refer to a ZIP file,
+ then a new ZIP archive is appended to the file. This is meant for adding a ZIP
+ archive to another file, such as :file:`python.exe`. Using ::
+
+ cat myzip.zip >> python.exe
+
+ also works, and at least :program:`WinZip` can read such files. If *mode* is
+ ``a`` and the file does not exist at all, it is created. *compression* is the
+ ZIP compression method to use when writing the archive, and should be
+ :const:`ZIP_STORED` or :const:`ZIP_DEFLATED`; unrecognized values will cause
+ :exc:`RuntimeError` to be raised. If :const:`ZIP_DEFLATED` is specified but the
+ :mod:`zlib` module is not available, :exc:`RuntimeError` is also raised. The
+ default is :const:`ZIP_STORED`. If *allowZip64* is ``True`` zipfile will create
+ ZIP files that use the ZIP64 extensions when the zipfile is larger than 2 GB. If
+ it is false (the default) :mod:`zipfile` will raise an exception when the ZIP
+ file would require ZIP64 extensions. ZIP64 extensions are disabled by default
+ because the default :program:`zip` and :program:`unzip` commands on Unix (the
+ InfoZIP utilities) don't support these extensions.
+
+ .. versionchanged:: 2.6
+ If the file does not exist, it is created if the mode is 'a'.
+
+
+.. method:: ZipFile.close()
+
+ Close the archive file. You must call :meth:`close` before exiting your program
+ or essential records will not be written.
+
+
+.. method:: ZipFile.getinfo(name)
+
+ Return a :class:`ZipInfo` object with information about the archive member
+ *name*. Calling :meth:`getinfo` for a name not currently contained in the
+ archive will raise a :exc:`KeyError`.
+
+
+.. method:: ZipFile.infolist()
+
+ Return a list containing a :class:`ZipInfo` object for each member of the
+ archive. The objects are in the same order as their entries in the actual ZIP
+ file on disk if an existing archive was opened.
+
+
+.. method:: ZipFile.namelist()
+
+ Return a list of archive members by name.
+
+
+.. method:: ZipFile.open(name[, mode[, pwd]])
+
+ Extract a member from the archive as a file-like object (ZipExtFile). *name* is
+ the name of the file in the archive. The *mode* parameter, if included, must be
+ one of the following: ``'r'`` (the default), ``'U'``, or ``'rU'``. Choosing
+ ``'U'`` or ``'rU'`` will enable universal newline support in the read-only
+ object. *pwd* is the password used for encrypted files. Calling :meth:`open`
+ on a closed ZipFile will raise a :exc:`RuntimeError`.
+
+ .. note::
+
+ The file-like object is read-only and provides the following methods:
+ :meth:`read`, :meth:`readline`, :meth:`readlines`, :meth:`__iter__`,
+ :meth:`next`.
+
+ .. note::
+
+ If the ZipFile was created by passing in a file-like object as the first
+ argument to the constructor, then the object returned by :meth:`open` shares the
+ ZipFile's file pointer. Under these circumstances, the object returned by
+ :meth:`open` should not be used after any additional operations are performed
+ on the ZipFile object. If the ZipFile was created by passing in a string (the
+ filename) as the first argument to the constructor, then :meth:`open` will
+ create a new file object that will be held by the ZipExtFile, allowing it to
+ operate independently of the ZipFile.
+
+ .. versionadded:: 2.6
+
+
+.. method:: ZipFile.printdir()
+
+ Print a table of contents for the archive to ``sys.stdout``.
+
+
+.. method:: ZipFile.setpassword(pwd)
+
+ Set *pwd* as default password to extract encrypted files.
+
+ .. versionadded:: 2.6
+
+
+.. method:: ZipFile.read(name[, pwd])
+
+ Return the bytes of the file in the archive. The archive must be open for read
+ or append. *pwd* is the password used for encrypted files and, if specified, it
+ will override the default password set with :meth:`setpassword`. Calling
+ :meth:`read` on a closed ZipFile will raise a :exc:`RuntimeError`.
+
+ .. versionchanged:: 2.6
+ *pwd* was added.
+
+
+.. method:: ZipFile.testzip()
+
+ Read all the files in the archive and check their CRC's and file headers.
+ Return the name of the first bad file, or else return ``None``. Calling
+ :meth:`testzip` on a closed ZipFile will raise a :exc:`RuntimeError`.
+
+
+.. method:: ZipFile.write(filename[, arcname[, compress_type]])
+
+ Write the file named *filename* to the archive, giving it the archive name
+ *arcname* (by default, this will be the same as *filename*, but without a drive
+ letter and with leading path separators removed). If given, *compress_type*
+ overrides the value given for the *compression* parameter to the constructor for
+ the new entry. The archive must be open with mode ``'w'`` or ``'a'`` -- calling
+ :meth:`write` on a ZipFile created with mode ``'r'`` will raise a
+ :exc:`RuntimeError`. Calling :meth:`write` on a closed ZipFile will raise a
+ :exc:`RuntimeError`.
+
+ .. note::
+
+ There is no official file name encoding for ZIP files. If you have unicode file
+ names, please convert them to byte strings in your desired encoding before
+ passing them to :meth:`write`. WinZip interprets all file names as encoded in
+ CP437, also known as DOS Latin.
+
+ .. note::
+
+ Archive names should be relative to the archive root, that is, they should not
+ start with a path separator.
+
+ .. note::
+
+ If ``arcname`` (or ``filename``, if ``arcname`` is not given) contains a null
+ byte, the name of the file in the archive will be truncated at the null byte.
+
+
+.. method:: ZipFile.writestr(zinfo_or_arcname, bytes)
+
+ Write the string *bytes* to the archive; *zinfo_or_arcname* is either the file
+ name it will be given in the archive, or a :class:`ZipInfo` instance. If it's
+ an instance, at least the filename, date, and time must be given. If it's a
+ name, the date and time is set to the current date and time. The archive must be
+ opened with mode ``'w'`` or ``'a'`` -- calling :meth:`writestr` on a ZipFile
+ created with mode ``'r'`` will raise a :exc:`RuntimeError`. Calling
+ :meth:`writestr` on a closed ZipFile will raise a :exc:`RuntimeError`.
+
+The following data attribute is also available:
+
+
+.. attribute:: ZipFile.debug
+
+ The level of debug output to use. This may be set from ``0`` (the default, no
+ output) to ``3`` (the most output). Debugging information is written to
+ ``sys.stdout``.
+
+
+.. _pyzipfile-objects:
+
+PyZipFile Objects
+-----------------
+
+The :class:`PyZipFile` constructor takes the same parameters as the
+:class:`ZipFile` constructor. Instances have one method in addition to those of
+:class:`ZipFile` objects.
+
+
+.. method:: PyZipFile.writepy(pathname[, basename])
+
+ Search for files :file:`\*.py` and add the corresponding file to the archive.
+ The corresponding file is a :file:`\*.pyo` file if available, else a
+ :file:`\*.pyc` file, compiling if necessary. If the pathname is a file, the
+ filename must end with :file:`.py`, and just the (corresponding
+ :file:`\*.py[co]`) file is added at the top level (no path information). If the
+ pathname is a file that does not end with :file:`.py`, a :exc:`RuntimeError`
+ will be raised. If it is a directory, and the directory is not a package
+ directory, then all the files :file:`\*.py[co]` are added at the top level. If
+ the directory is a package directory, then all :file:`\*.py[co]` are added under
+ the package name as a file path, and if any subdirectories are package
+ directories, all of these are added recursively. *basename* is intended for
+ internal use only. The :meth:`writepy` method makes archives with file names
+ like this::
+
+ string.pyc # Top level name
+ test/__init__.pyc # Package directory
+ test/testall.pyc # Module test.testall
+ test/bogus/__init__.pyc # Subpackage directory
+ test/bogus/myfile.pyc # Submodule test.bogus.myfile
+
+
+.. _zipinfo-objects:
+
+ZipInfo Objects
+---------------
+
+Instances of the :class:`ZipInfo` class are returned by the :meth:`getinfo` and
+:meth:`infolist` methods of :class:`ZipFile` objects. Each object stores
+information about a single member of the ZIP archive.
+
+Instances have the following attributes:
+
+
+.. attribute:: ZipInfo.filename
+
+ Name of the file in the archive.
+
+
+.. attribute:: ZipInfo.date_time
+
+ The time and date of the last modification to the archive member. This is a
+ tuple of six values:
+
+ +-------+--------------------------+
+ | Index | Value |
+ +=======+==========================+
+ | ``0`` | Year |
+ +-------+--------------------------+
+ | ``1`` | Month (one-based) |
+ +-------+--------------------------+
+ | ``2`` | Day of month (one-based) |
+ +-------+--------------------------+
+ | ``3`` | Hours (zero-based) |
+ +-------+--------------------------+
+ | ``4`` | Minutes (zero-based) |
+ +-------+--------------------------+
+ | ``5`` | Seconds (zero-based) |
+ +-------+--------------------------+
+
+
+.. attribute:: ZipInfo.compress_type
+
+ Type of compression for the archive member.
+
+
+.. attribute:: ZipInfo.comment
+
+ Comment for the individual archive member.
+
+
+.. attribute:: ZipInfo.extra
+
+ Expansion field data. The `PKZIP Application Note
+ <http://www.pkware.com/business_and_developers/developer/appnote/>`_ contains
+ some comments on the internal structure of the data contained in this string.
+
+
+.. attribute:: ZipInfo.create_system
+
+ System which created ZIP archive.
+
+
+.. attribute:: ZipInfo.create_version
+
+ PKZIP version which created ZIP archive.
+
+
+.. attribute:: ZipInfo.extract_version
+
+ PKZIP version needed to extract archive.
+
+
+.. attribute:: ZipInfo.reserved
+
+ Must be zero.
+
+
+.. attribute:: ZipInfo.flag_bits
+
+ ZIP flag bits.
+
+
+.. attribute:: ZipInfo.volume
+
+ Volume number of file header.
+
+
+.. attribute:: ZipInfo.internal_attr
+
+ Internal attributes.
+
+
+.. attribute:: ZipInfo.external_attr
+
+ External file attributes.
+
+
+.. attribute:: ZipInfo.header_offset
+
+ Byte offset to the file header.
+
+
+.. attribute:: ZipInfo.CRC
+
+ CRC-32 of the uncompressed file.
+
+
+.. attribute:: ZipInfo.compress_size
+
+ Size of the compressed data.
+
+
+.. attribute:: ZipInfo.file_size
+
+ Size of the uncompressed file.
+
diff --git a/Doc/library/zipimport.rst b/Doc/library/zipimport.rst
new file mode 100644
index 0000000000..f2b23586a2
--- /dev/null
+++ b/Doc/library/zipimport.rst
@@ -0,0 +1,137 @@
+
+:mod:`zipimport` --- Import modules from Zip archives
+=====================================================
+
+.. module:: zipimport
+ :synopsis: support for importing Python modules from ZIP archives.
+.. moduleauthor:: Just van Rossum <just@letterror.com>
+
+
+.. versionadded:: 2.3
+
+This module adds the ability to import Python modules (:file:`\*.py`,
+:file:`\*.py[co]`) and packages from ZIP-format archives. It is usually not
+needed to use the :mod:`zipimport` module explicitly; it is automatically used
+by the builtin :keyword:`import` mechanism for ``sys.path`` items that are paths
+to ZIP archives.
+
+Typically, ``sys.path`` is a list of directory names as strings. This module
+also allows an item of ``sys.path`` to be a string naming a ZIP file archive.
+The ZIP archive can contain a subdirectory structure to support package imports,
+and a path within the archive can be specified to only import from a
+subdirectory. For example, the path :file:`/tmp/example.zip/lib/` would only
+import from the :file:`lib/` subdirectory within the archive.
+
+Any files may be present in the ZIP archive, but only files :file:`.py` and
+:file:`.py[co]` are available for import. ZIP import of dynamic modules
+(:file:`.pyd`, :file:`.so`) is disallowed. Note that if an archive only contains
+:file:`.py` files, Python will not attempt to modify the archive by adding the
+corresponding :file:`.pyc` or :file:`.pyo` file, meaning that if a ZIP archive
+doesn't contain :file:`.pyc` files, importing may be rather slow.
+
+The available attributes of this module are:
+
+
+.. exception:: ZipImportError
+
+ Exception raised by zipimporter objects. It's a subclass of :exc:`ImportError`,
+ so it can be caught as :exc:`ImportError`, too.
+
+
+.. class:: zipimporter
+
+ The class for importing ZIP files. See section :ref:`zipimporter-objects`
+ for constructor details.
+
+
+.. seealso::
+
+ `PKZIP Application Note <http://www.pkware.com/business_and_developers/developer/appnote/>`_
+ Documentation on the ZIP file format by Phil Katz, the creator of the format and
+ algorithms used.
+
+ :pep:`0273` - Import Modules from Zip Archives
+ Written by James C. Ahlstrom, who also provided an implementation. Python 2.3
+ follows the specification in PEP 273, but uses an implementation written by Just
+ van Rossum that uses the import hooks described in PEP 302.
+
+ :pep:`0302` - New Import Hooks
+ The PEP to add the import hooks that help this module work.
+
+
+.. _zipimporter-objects:
+
+zipimporter Objects
+-------------------
+
+
+.. class:: zipimporter(archivepath)
+
+ Create a new zipimporter instance. *archivepath* must be a path to a zipfile.
+ :exc:`ZipImportError` is raised if *archivepath* doesn't point to a valid ZIP
+ archive.
+
+
+.. method:: zipimporter.find_module(fullname[, path])
+
+ Search for a module specified by *fullname*. *fullname* must be the fully
+ qualified (dotted) module name. It returns the zipimporter instance itself if
+ the module was found, or :const:`None` if it wasn't. The optional *path*
+ argument is ignored---it's there for compatibility with the importer protocol.
+
+
+.. method:: zipimporter.get_code(fullname)
+
+ Return the code object for the specified module. Raise :exc:`ZipImportError` if
+ the module couldn't be found.
+
+
+.. method:: zipimporter.get_data(pathname)
+
+ Return the data associated with *pathname*. Raise :exc:`IOError` if the file
+ wasn't found.
+
+
+.. method:: zipimporter.get_source(fullname)
+
+ Return the source code for the specified module. Raise :exc:`ZipImportError` if
+ the module couldn't be found, return :const:`None` if the archive does contain
+ the module, but has no source for it.
+
+
+.. method:: zipimporter.is_package(fullname)
+
+ Return True if the module specified by *fullname* is a package. Raise
+ :exc:`ZipImportError` if the module couldn't be found.
+
+
+.. method:: zipimporter.load_module(fullname)
+
+ Load the module specified by *fullname*. *fullname* must be the fully qualified
+ (dotted) module name. It returns the imported module, or raises
+ :exc:`ZipImportError` if it wasn't found.
+
+
+Examples
+--------
+
+.. _zipimport-examples:
+
+Here is an example that imports a module from a ZIP archive - note that the
+:mod:`zipimport` module is not explicitly used. ::
+
+ $ unzip -l /tmp/example.zip
+ Archive: /tmp/example.zip
+ Length Date Time Name
+ -------- ---- ---- ----
+ 8467 11-26-02 22:30 jwzthreading.py
+ -------- -------
+ 8467 1 file
+ $ ./python
+ Python 2.3 (#1, Aug 1 2003, 19:54:32)
+ >>> import sys
+ >>> sys.path.insert(0, '/tmp/example.zip') # Add .zip file to front of path
+ >>> import jwzthreading
+ >>> jwzthreading.__file__
+ '/tmp/example.zip/jwzthreading.py'
+
diff --git a/Doc/library/zlib.rst b/Doc/library/zlib.rst
new file mode 100644
index 0000000000..e57a1562c2
--- /dev/null
+++ b/Doc/library/zlib.rst
@@ -0,0 +1,209 @@
+
+:mod:`zlib` --- Compression compatible with :program:`gzip`
+===========================================================
+
+.. module:: zlib
+ :synopsis: Low-level interface to compression and decompression routines compatible with
+ gzip.
+
+
+For applications that require data compression, the functions in this module
+allow compression and decompression, using the zlib library. The zlib library
+has its own home page at http://www.zlib.net. There are known
+incompatibilities between the Python module and versions of the zlib library
+earlier than 1.1.3; 1.1.3 has a security vulnerability, so we recommend using
+1.1.4 or later.
+
+zlib's functions have many options and often need to be used in a particular
+order. This documentation doesn't attempt to cover all of the permutations;
+consult the zlib manual at http://www.zlib.net/manual.html for authoritative
+information.
+
+The available exception and functions in this module are:
+
+
+.. exception:: error
+
+ Exception raised on compression and decompression errors.
+
+
+.. function:: adler32(string[, value])
+
+ Computes a Adler-32 checksum of *string*. (An Adler-32 checksum is almost as
+ reliable as a CRC32 but can be computed much more quickly.) If *value* is
+ present, it is used as the starting value of the checksum; otherwise, a fixed
+ default value is used. This allows computing a running checksum over the
+ concatenation of several input strings. The algorithm is not cryptographically
+ strong, and should not be used for authentication or digital signatures. Since
+ the algorithm is designed for use as a checksum algorithm, it is not suitable
+ for use as a general hash algorithm.
+
+
+.. function:: compress(string[, level])
+
+ Compresses the data in *string*, returning a string contained compressed data.
+ *level* is an integer from ``1`` to ``9`` controlling the level of compression;
+ ``1`` is fastest and produces the least compression, ``9`` is slowest and
+ produces the most. The default value is ``6``. Raises the :exc:`error`
+ exception if any error occurs.
+
+
+.. function:: compressobj([level])
+
+ Returns a compression object, to be used for compressing data streams that won't
+ fit into memory at once. *level* is an integer from ``1`` to ``9`` controlling
+ the level of compression; ``1`` is fastest and produces the least compression,
+ ``9`` is slowest and produces the most. The default value is ``6``.
+
+
+.. function:: crc32(string[, value])
+
+ .. index::
+ single: Cyclic Redundancy Check
+ single: checksum; Cyclic Redundancy Check
+
+ Computes a CRC (Cyclic Redundancy Check) checksum of *string*. If *value* is
+ present, it is used as the starting value of the checksum; otherwise, a fixed
+ default value is used. This allows computing a running checksum over the
+ concatenation of several input strings. The algorithm is not cryptographically
+ strong, and should not be used for authentication or digital signatures. Since
+ the algorithm is designed for use as a checksum algorithm, it is not suitable
+ for use as a general hash algorithm.
+
+ .. %
+
+
+.. function:: decompress(string[, wbits[, bufsize]])
+
+ Decompresses the data in *string*, returning a string containing the
+ uncompressed data. The *wbits* parameter controls the size of the window
+ buffer. If *bufsize* is given, it is used as the initial size of the output
+ buffer. Raises the :exc:`error` exception if any error occurs.
+
+ The absolute value of *wbits* is the base two logarithm of the size of the
+ history buffer (the "window size") used when compressing data. Its absolute
+ value should be between 8 and 15 for the most recent versions of the zlib
+ library, larger values resulting in better compression at the expense of greater
+ memory usage. The default value is 15. When *wbits* is negative, the standard
+ :program:`gzip` header is suppressed; this is an undocumented feature of the
+ zlib library, used for compatibility with :program:`unzip`'s compression file
+ format.
+
+ *bufsize* is the initial size of the buffer used to hold decompressed data. If
+ more space is required, the buffer size will be increased as needed, so you
+ don't have to get this value exactly right; tuning it will only save a few calls
+ to :cfunc:`malloc`. The default size is 16384.
+
+
+.. function:: decompressobj([wbits])
+
+ Returns a decompression object, to be used for decompressing data streams that
+ won't fit into memory at once. The *wbits* parameter controls the size of the
+ window buffer.
+
+Compression objects support the following methods:
+
+
+.. method:: Compress.compress(string)
+
+ Compress *string*, returning a string containing compressed data for at least
+ part of the data in *string*. This data should be concatenated to the output
+ produced by any preceding calls to the :meth:`compress` method. Some input may
+ be kept in internal buffers for later processing.
+
+
+.. method:: Compress.flush([mode])
+
+ All pending input is processed, and a string containing the remaining compressed
+ output is returned. *mode* can be selected from the constants
+ :const:`Z_SYNC_FLUSH`, :const:`Z_FULL_FLUSH`, or :const:`Z_FINISH`,
+ defaulting to :const:`Z_FINISH`. :const:`Z_SYNC_FLUSH` and
+ :const:`Z_FULL_FLUSH` allow compressing further strings of data, while
+ :const:`Z_FINISH` finishes the compressed stream and prevents compressing any
+ more data. After calling :meth:`flush` with *mode* set to :const:`Z_FINISH`,
+ the :meth:`compress` method cannot be called again; the only realistic action is
+ to delete the object.
+
+
+.. method:: Compress.copy()
+
+ Returns a copy of the compression object. This can be used to efficiently
+ compress a set of data that share a common initial prefix.
+
+ .. versionadded:: 2.5
+
+Decompression objects support the following methods, and two attributes:
+
+
+.. attribute:: Decompress.unused_data
+
+ A string which contains any bytes past the end of the compressed data. That is,
+ this remains ``""`` until the last byte that contains compression data is
+ available. If the whole string turned out to contain compressed data, this is
+ ``""``, the empty string.
+
+ The only way to determine where a string of compressed data ends is by actually
+ decompressing it. This means that when compressed data is contained part of a
+ larger file, you can only find the end of it by reading data and feeding it
+ followed by some non-empty string into a decompression object's
+ :meth:`decompress` method until the :attr:`unused_data` attribute is no longer
+ the empty string.
+
+
+.. attribute:: Decompress.unconsumed_tail
+
+ A string that contains any data that was not consumed by the last
+ :meth:`decompress` call because it exceeded the limit for the uncompressed data
+ buffer. This data has not yet been seen by the zlib machinery, so you must feed
+ it (possibly with further data concatenated to it) back to a subsequent
+ :meth:`decompress` method call in order to get correct output.
+
+
+.. method:: Decompress.decompress(string[, max_length])
+
+ Decompress *string*, returning a string containing the uncompressed data
+ corresponding to at least part of the data in *string*. This data should be
+ concatenated to the output produced by any preceding calls to the
+ :meth:`decompress` method. Some of the input data may be preserved in internal
+ buffers for later processing.
+
+ If the optional parameter *max_length* is supplied then the return value will be
+ no longer than *max_length*. This may mean that not all of the compressed input
+ can be processed; and unconsumed data will be stored in the attribute
+ :attr:`unconsumed_tail`. This string must be passed to a subsequent call to
+ :meth:`decompress` if decompression is to continue. If *max_length* is not
+ supplied then the whole input is decompressed, and :attr:`unconsumed_tail` is an
+ empty string.
+
+
+.. method:: Decompress.flush([length])
+
+ All pending input is processed, and a string containing the remaining
+ uncompressed output is returned. After calling :meth:`flush`, the
+ :meth:`decompress` method cannot be called again; the only realistic action is
+ to delete the object.
+
+ The optional parameter *length* sets the initial size of the output buffer.
+
+
+.. method:: Decompress.copy()
+
+ Returns a copy of the decompression object. This can be used to save the state
+ of the decompressor midway through the data stream in order to speed up random
+ seeks into the stream at a future point.
+
+ .. versionadded:: 2.5
+
+
+.. seealso::
+
+ Module :mod:`gzip`
+ Reading and writing :program:`gzip`\ -format files.
+
+ http://www.zlib.net
+ The zlib library home page.
+
+ http://www.zlib.net/manual.html
+ The zlib manual explains the semantics and usage of the library's many
+ functions.
+
diff --git a/Doc/license.rst b/Doc/license.rst
new file mode 100644
index 0000000000..a9165f43f6
--- /dev/null
+++ b/Doc/license.rst
@@ -0,0 +1,647 @@
+.. highlightlang:: none
+
+.. _history-and-license:
+
+*******************
+History and License
+*******************
+
+
+History of the software
+=======================
+
+Python was created in the early 1990s by Guido van Rossum at Stichting
+Mathematisch Centrum (CWI, see http://www.cwi.nl/) in the Netherlands as a
+successor of a language called ABC. Guido remains Python's principal author,
+although it includes many contributions from others.
+
+In 1995, Guido continued his work on Python at the Corporation for National
+Research Initiatives (CNRI, see http://www.cnri.reston.va.us/) in Reston,
+Virginia where he released several versions of the software.
+
+In May 2000, Guido and the Python core development team moved to BeOpen.com to
+form the BeOpen PythonLabs team. In October of the same year, the PythonLabs
+team moved to Digital Creations (now Zope Corporation; see
+http://www.zope.com/). In 2001, the Python Software Foundation (PSF, see
+http://www.python.org/psf/) was formed, a non-profit organization created
+specifically to own Python-related Intellectual Property. Zope Corporation is a
+sponsoring member of the PSF.
+
+All Python releases are Open Source (see http://www.opensource.org/ for the Open
+Source Definition). Historically, most, but not all, Python releases have also
+been GPL-compatible; the table below summarizes the various releases.
+
++----------------+--------------+-----------+------------+-----------------+
+| Release | Derived from | Year | Owner | GPL compatible? |
++================+==============+===========+============+=================+
+| 0.9.0 thru 1.2 | n/a | 1991-1995 | CWI | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 1.3 thru 1.5.2 | 1.2 | 1995-1999 | CNRI | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 1.6 | 1.5.2 | 2000 | CNRI | no |
++----------------+--------------+-----------+------------+-----------------+
+| 2.0 | 1.6 | 2000 | BeOpen.com | no |
++----------------+--------------+-----------+------------+-----------------+
+| 1.6.1 | 1.6 | 2001 | CNRI | no |
++----------------+--------------+-----------+------------+-----------------+
+| 2.1 | 2.0+1.6.1 | 2001 | PSF | no |
++----------------+--------------+-----------+------------+-----------------+
+| 2.0.1 | 2.0+1.6.1 | 2001 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.1.1 | 2.1+2.0.1 | 2001 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.2 | 2.1.1 | 2001 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.1.2 | 2.1.1 | 2002 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.1.3 | 2.1.2 | 2002 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.2.1 | 2.2 | 2002 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.2.2 | 2.2.1 | 2002 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.2.3 | 2.2.2 | 2002-2003 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.3 | 2.2.2 | 2002-2003 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.3.1 | 2.3 | 2002-2003 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.3.2 | 2.3.1 | 2003 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.3.3 | 2.3.2 | 2003 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.3.4 | 2.3.3 | 2004 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.3.5 | 2.3.4 | 2005 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.4 | 2.3 | 2004 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.4.1 | 2.4 | 2005 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.4.2 | 2.4.1 | 2005 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.4.3 | 2.4.2 | 2006 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.4.4 | 2.4.3 | 2006 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.5 | 2.4 | 2006 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+| 2.5.1 | 2.5 | 2007 | PSF | yes |
++----------------+--------------+-----------+------------+-----------------+
+
+.. note::
+
+ GPL-compatible doesn't mean that we're distributing Python under the GPL. All
+ Python licenses, unlike the GPL, let you distribute a modified version without
+ making your changes open source. The GPL-compatible licenses make it possible to
+ combine Python with other software that is released under the GPL; the others
+ don't.
+
+Thanks to the many outside volunteers who have worked under Guido's direction to
+make these releases possible.
+
+
+Terms and conditions for accessing or otherwise using Python
+============================================================
+
+
+.. centered:: PSF LICENSE AGREEMENT FOR PYTHON |release|
+
+#. This LICENSE AGREEMENT is between the Python Software Foundation ("PSF"), and
+ the Individual or Organization ("Licensee") accessing and otherwise using Python
+ |release| software in source or binary form and its associated documentation.
+
+#. Subject to the terms and conditions of this License Agreement, PSF hereby
+ grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
+ analyze, test, perform and/or display publicly, prepare derivative works,
+ distribute, and otherwise use Python |release| alone or in any derivative
+ version, provided, however, that PSF's License Agreement and PSF's notice of
+ copyright, i.e., "Copyright © 2001-2007 Python Software Foundation; All Rights
+ Reserved" are retained in Python |release| alone or in any derivative version
+ prepared by Licensee.
+
+#. In the event Licensee prepares a derivative work that is based on or
+ incorporates Python |release| or any part thereof, and wants to make the
+ derivative work available to others as provided herein, then Licensee hereby
+ agrees to include in any such work a brief summary of the changes made to Python
+ |release|.
+
+#. PSF is making Python |release| available to Licensee on an "AS IS" basis.
+ PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. BY WAY OF
+ EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND DISCLAIMS ANY REPRESENTATION OR
+ WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE
+ USE OF PYTHON |release| WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.
+
+#. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON |release|
+ FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF
+ MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON |release|, OR ANY DERIVATIVE
+ THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+#. This License Agreement will automatically terminate upon a material breach of
+ its terms and conditions.
+
+#. Nothing in this License Agreement shall be deemed to create any relationship
+ of agency, partnership, or joint venture between PSF and Licensee. This License
+ Agreement does not grant permission to use PSF trademarks or trade name in a
+ trademark sense to endorse or promote products or services of Licensee, or any
+ third party.
+
+#. By copying, installing or otherwise using Python |release|, Licensee agrees
+ to be bound by the terms and conditions of this License Agreement.
+
+
+.. centered:: BEOPEN.COM LICENSE AGREEMENT FOR PYTHON 2.0
+
+
+.. centered:: BEOPEN PYTHON OPEN SOURCE LICENSE AGREEMENT VERSION 1
+
+#. This LICENSE AGREEMENT is between BeOpen.com ("BeOpen"), having an office at
+ 160 Saratoga Avenue, Santa Clara, CA 95051, and the Individual or Organization
+ ("Licensee") accessing and otherwise using this software in source or binary
+ form and its associated documentation ("the Software").
+
+#. Subject to the terms and conditions of this BeOpen Python License Agreement,
+ BeOpen hereby grants Licensee a non-exclusive, royalty-free, world-wide license
+ to reproduce, analyze, test, perform and/or display publicly, prepare derivative
+ works, distribute, and otherwise use the Software alone or in any derivative
+ version, provided, however, that the BeOpen Python License is retained in the
+ Software, alone or in any derivative version prepared by Licensee.
+
+#. BeOpen is making the Software available to Licensee on an "AS IS" basis.
+ BEOPEN MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. BY WAY OF
+ EXAMPLE, BUT NOT LIMITATION, BEOPEN MAKES NO AND DISCLAIMS ANY REPRESENTATION OR
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+ USE OF THE SOFTWARE WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.
+
+#. BEOPEN SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF THE SOFTWARE FOR
+ ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF USING,
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+
+#. This License Agreement will automatically terminate upon a material breach of
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+
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+ granted on that web page.
+
+#. By copying, installing or otherwise using the software, Licensee agrees to be
+ bound by the terms and conditions of this License Agreement.
+
+
+.. centered:: CNRI LICENSE AGREEMENT FOR PYTHON 1.6.1
+
+#. This LICENSE AGREEMENT is between the Corporation for National Research
+ Initiatives, having an office at 1895 Preston White Drive, Reston, VA 20191
+ ("CNRI"), and the Individual or Organization ("Licensee") accessing and
+ otherwise using Python 1.6.1 software in source or binary form and its
+ associated documentation.
+
+#. Subject to the terms and conditions of this License Agreement, CNRI hereby
+ grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
+ analyze, test, perform and/or display publicly, prepare derivative works,
+ distribute, and otherwise use Python 1.6.1 alone or in any derivative version,
+ provided, however, that CNRI's License Agreement and CNRI's notice of copyright,
+ i.e., "Copyright © 1995-2001 Corporation for National Research Initiatives; All
+ Rights Reserved" are retained in Python 1.6.1 alone or in any derivative version
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+ Licensee may substitute the following text (omitting the quotes): "Python 1.6.1
+ is made available subject to the terms and conditions in CNRI's License
+ Agreement. This Agreement together with Python 1.6.1 may be located on the
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+ 1895.22/1013. This Agreement may also be obtained from a proxy server on the
+ Internet using the following URL: http://hdl.handle.net/1895.22/1013."
+
+#. In the event Licensee prepares a derivative work that is based on or
+ incorporates Python 1.6.1 or any part thereof, and wants to make the derivative
+ work available to others as provided herein, then Licensee hereby agrees to
+ include in any such work a brief summary of the changes made to Python 1.6.1.
+
+#. CNRI is making Python 1.6.1 available to Licensee on an "AS IS" basis. CNRI
+ MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. BY WAY OF EXAMPLE,
+ BUT NOT LIMITATION, CNRI MAKES NO AND DISCLAIMS ANY REPRESENTATION OR WARRANTY
+ OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF
+ PYTHON 1.6.1 WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.
+
+#. CNRI SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON 1.6.1 FOR
+ ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF
+ MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 1.6.1, OR ANY DERIVATIVE
+ THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+#. This License Agreement will automatically terminate upon a material breach of
+ its terms and conditions.
+
+#. This License Agreement shall be governed by the federal intellectual property
+ law of the United States, including without limitation the federal copyright
+ law, and, to the extent such U.S. federal law does not apply, by the law of the
+ Commonwealth of Virginia, excluding Virginia's conflict of law provisions.
+ Notwithstanding the foregoing, with regard to derivative works based on Python
+ 1.6.1 that incorporate non-separable material that was previously distributed
+ under the GNU General Public License (GPL), the law of the Commonwealth of
+ Virginia shall govern this License Agreement only as to issues arising under or
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+ this License Agreement shall be deemed to create any relationship of agency,
+ partnership, or joint venture between CNRI and Licensee. This License Agreement
+ does not grant permission to use CNRI trademarks or trade name in a trademark
+ sense to endorse or promote products or services of Licensee, or any third
+ party.
+
+#. By clicking on the "ACCEPT" button where indicated, or by copying, installing
+ or otherwise using Python 1.6.1, Licensee agrees to be bound by the terms and
+ conditions of this License Agreement.
+
+
+.. centered:: ACCEPT
+
+
+.. centered:: CWI LICENSE AGREEMENT FOR PYTHON 0.9.0 THROUGH 1.2
+
+Copyright © 1991 - 1995, Stichting Mathematisch Centrum Amsterdam, The
+Netherlands. All rights reserved.
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted, provided that
+the above copyright notice appear in all copies and that both that copyright
+notice and this permission notice appear in supporting documentation, and that
+the name of Stichting Mathematisch Centrum or CWI not be used in advertising or
+publicity pertaining to distribution of the software without specific, written
+prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE FOR ANY SPECIAL, INDIRECT
+OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+
+Licenses and Acknowledgements for Incorporated Software
+=======================================================
+
+This section is an incomplete, but growing list of licenses and acknowledgements
+for third-party software incorporated in the Python distribution.
+
+
+Mersenne Twister
+----------------
+
+The :mod:`_random` module includes code based on a download from
+http://www.math.keio.ac.jp/ matumoto/MT2002/emt19937ar.html. The following are
+the verbatim comments from the original code::
+
+ A C-program for MT19937, with initialization improved 2002/1/26.
+ Coded by Takuji Nishimura and Makoto Matsumoto.
+
+ Before using, initialize the state by using init_genrand(seed)
+ or init_by_array(init_key, key_length).
+
+ Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ 3. The names of its contributors may not be used to endorse or promote
+ products derived from this software without specific prior written
+ permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+ Any feedback is very welcome.
+ http://www.math.keio.ac.jp/matumoto/emt.html
+ email: matumoto@math.keio.ac.jp
+
+
+Sockets
+-------
+
+The :mod:`socket` module uses the functions, :func:`getaddrinfo`, and
+:func:`getnameinfo`, which are coded in separate source files from the WIDE
+Project, http://www.wide.ad.jp/about/index.html. ::
+
+ Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+ 3. Neither the name of the project nor the names of its contributors
+ may be used to endorse or promote products derived from this software
+ without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
+ GAI_ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
+ FOR GAI_ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ HOWEVER CAUSED AND ON GAI_ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN GAI_ANY WAY
+ OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ SUCH DAMAGE.
+
+
+Floating point exception control
+--------------------------------
+
+The source for the :mod:`fpectl` module includes the following notice::
+
+ ---------------------------------------------------------------------
+ / Copyright (c) 1996. \
+ | The Regents of the University of California. |
+ | All rights reserved. |
+ | |
+ | Permission to use, copy, modify, and distribute this software for |
+ | any purpose without fee is hereby granted, provided that this en- |
+ | tire notice is included in all copies of any software which is or |
+ | includes a copy or modification of this software and in all |
+ | copies of the supporting documentation for such software. |
+ | |
+ | This work was produced at the University of California, Lawrence |
+ | Livermore National Laboratory under contract no. W-7405-ENG-48 |
+ | between the U.S. Department of Energy and The Regents of the |
+ | University of California for the operation of UC LLNL. |
+ | |
+ | DISCLAIMER |
+ | |
+ | This software was prepared as an account of work sponsored by an |
+ | agency of the United States Government. Neither the United States |
+ | Government nor the University of California nor any of their em- |
+ | ployees, makes any warranty, express or implied, or assumes any |
+ | liability or responsibility for the accuracy, completeness, or |
+ | usefulness of any information, apparatus, product, or process |
+ | disclosed, or represents that its use would not infringe |
+ | privately-owned rights. Reference herein to any specific commer- |
+ | cial products, process, or service by trade name, trademark, |
+ | manufacturer, or otherwise, does not necessarily constitute or |
+ | imply its endorsement, recommendation, or favoring by the United |
+ | States Government or the University of California. The views and |
+ | opinions of authors expressed herein do not necessarily state or |
+ | reflect those of the United States Government or the University |
+ | of California, and shall not be used for advertising or product |
+ \ endorsement purposes. /
+ ---------------------------------------------------------------------
+
+
+MD5 message digest algorithm
+----------------------------
+
+The source code for the :mod:`md5` module contains the following notice::
+
+ Copyright (C) 1999, 2002 Aladdin Enterprises. All rights reserved.
+
+ This software is provided 'as-is', without any express or implied
+ warranty. In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+
+ L. Peter Deutsch
+ ghost@aladdin.com
+
+ Independent implementation of MD5 (RFC 1321).
+
+ This code implements the MD5 Algorithm defined in RFC 1321, whose
+ text is available at
+ http://www.ietf.org/rfc/rfc1321.txt
+ The code is derived from the text of the RFC, including the test suite
+ (section A.5) but excluding the rest of Appendix A. It does not include
+ any code or documentation that is identified in the RFC as being
+ copyrighted.
+
+ The original and principal author of md5.h is L. Peter Deutsch
+ <ghost@aladdin.com>. Other authors are noted in the change history
+ that follows (in reverse chronological order):
+
+ 2002-04-13 lpd Removed support for non-ANSI compilers; removed
+ references to Ghostscript; clarified derivation from RFC 1321;
+ now handles byte order either statically or dynamically.
+ 1999-11-04 lpd Edited comments slightly for automatic TOC extraction.
+ 1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5);
+ added conditionalization for C++ compilation from Martin
+ Purschke <purschke@bnl.gov>.
+ 1999-05-03 lpd Original version.
+
+
+Asynchronous socket services
+----------------------------
+
+The :mod:`asynchat` and :mod:`asyncore` modules contain the following notice::
+
+ Copyright 1996 by Sam Rushing
+
+ All Rights Reserved
+
+ Permission to use, copy, modify, and distribute this software and
+ its documentation for any purpose and without fee is hereby
+ granted, provided that the above copyright notice appear in all
+ copies and that both that copyright notice and this permission
+ notice appear in supporting documentation, and that the name of Sam
+ Rushing not be used in advertising or publicity pertaining to
+ distribution of the software without specific, written prior
+ permission.
+
+ SAM RUSHING DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+ NO EVENT SHALL SAM RUSHING BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+
+Cookie management
+-----------------
+
+The :mod:`Cookie` module contains the following notice::
+
+ Copyright 2000 by Timothy O'Malley <timo@alum.mit.edu>
+
+ All Rights Reserved
+
+ Permission to use, copy, modify, and distribute this software
+ and its documentation for any purpose and without fee is hereby
+ granted, provided that the above copyright notice appear in all
+ copies and that both that copyright notice and this permission
+ notice appear in supporting documentation, and that the name of
+ Timothy O'Malley not be used in advertising or publicity
+ pertaining to distribution of the software without specific, written
+ prior permission.
+
+ Timothy O'Malley DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ AND FITNESS, IN NO EVENT SHALL Timothy O'Malley BE LIABLE FOR
+ ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+ WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ PERFORMANCE OF THIS SOFTWARE.
+
+
+Profiling
+---------
+
+The :mod:`profile` and :mod:`pstats` modules contain the following notice::
+
+ Copyright 1994, by InfoSeek Corporation, all rights reserved.
+ Written by James Roskind
+
+ Permission to use, copy, modify, and distribute this Python software
+ and its associated documentation for any purpose (subject to the
+ restriction in the following sentence) without fee is hereby granted,
+ provided that the above copyright notice appears in all copies, and
+ that both that copyright notice and this permission notice appear in
+ supporting documentation, and that the name of InfoSeek not be used in
+ advertising or publicity pertaining to distribution of the software
+ without specific, written prior permission. This permission is
+ explicitly restricted to the copying and modification of the software
+ to remain in Python, compiled Python, or other languages (such as C)
+ wherein the modified or derived code is exclusively imported into a
+ Python module.
+
+ INFOSEEK CORPORATION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS. IN NO EVENT SHALL INFOSEEK CORPORATION BE LIABLE FOR ANY
+ SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+ RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
+ CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+
+Execution tracing
+-----------------
+
+The :mod:`trace` module contains the following notice::
+
+ portions copyright 2001, Autonomous Zones Industries, Inc., all rights...
+ err... reserved and offered to the public under the terms of the
+ Python 2.2 license.
+ Author: Zooko O'Whielacronx
+ http://zooko.com/
+ mailto:zooko@zooko.com
+
+ Copyright 2000, Mojam Media, Inc., all rights reserved.
+ Author: Skip Montanaro
+
+ Copyright 1999, Bioreason, Inc., all rights reserved.
+ Author: Andrew Dalke
+
+ Copyright 1995-1997, Automatrix, Inc., all rights reserved.
+ Author: Skip Montanaro
+
+ Copyright 1991-1995, Stichting Mathematisch Centrum, all rights reserved.
+
+
+ Permission to use, copy, modify, and distribute this Python software and
+ its associated documentation for any purpose without fee is hereby
+ granted, provided that the above copyright notice appears in all copies,
+ and that both that copyright notice and this permission notice appear in
+ supporting documentation, and that the name of neither Automatrix,
+ Bioreason or Mojam Media be used in advertising or publicity pertaining to
+ distribution of the software without specific, written prior permission.
+
+
+UUencode and UUdecode functions
+-------------------------------
+
+The :mod:`uu` module contains the following notice::
+
+ Copyright 1994 by Lance Ellinghouse
+ Cathedral City, California Republic, United States of America.
+ All Rights Reserved
+ Permission to use, copy, modify, and distribute this software and its
+ documentation for any purpose and without fee is hereby granted,
+ provided that the above copyright notice appear in all copies and that
+ both that copyright notice and this permission notice appear in
+ supporting documentation, and that the name of Lance Ellinghouse
+ not be used in advertising or publicity pertaining to distribution
+ of the software without specific, written prior permission.
+ LANCE ELLINGHOUSE DISCLAIMS ALL WARRANTIES WITH REGARD TO
+ THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS, IN NO EVENT SHALL LANCE ELLINGHOUSE CENTRUM BE LIABLE
+ FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+ Modified by Jack Jansen, CWI, July 1995:
+ - Use binascii module to do the actual line-by-line conversion
+ between ascii and binary. This results in a 1000-fold speedup. The C
+ version is still 5 times faster, though.
+ - Arguments more compliant with python standard
+
+
+XML Remote Procedure Calls
+--------------------------
+
+The :mod:`xmlrpclib` module contains the following notice::
+
+ The XML-RPC client interface is
+
+ Copyright (c) 1999-2002 by Secret Labs AB
+ Copyright (c) 1999-2002 by Fredrik Lundh
+
+ By obtaining, using, and/or copying this software and/or its
+ associated documentation, you agree that you have read, understood,
+ and will comply with the following terms and conditions:
+
+ Permission to use, copy, modify, and distribute this software and
+ its associated documentation for any purpose and without fee is
+ hereby granted, provided that the above copyright notice appears in
+ all copies, and that both that copyright notice and this permission
+ notice appear in supporting documentation, and that the name of
+ Secret Labs AB or the author not be used in advertising or publicity
+ pertaining to distribution of the software without specific, written
+ prior permission.
+
+ SECRET LABS AB AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
+ TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANT-
+ ABILITY AND FITNESS. IN NO EVENT SHALL SECRET LABS AB OR THE AUTHOR
+ BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
+ DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+ WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ OF THIS SOFTWARE.
+
diff --git a/Doc/reference/compound_stmts.rst b/Doc/reference/compound_stmts.rst
new file mode 100644
index 0000000000..e7587f6cc3
--- /dev/null
+++ b/Doc/reference/compound_stmts.rst
@@ -0,0 +1,554 @@
+
+.. _compound:
+
+*******************
+Compound statements
+*******************
+
+.. index:: pair: compound; statement
+
+Compound statements contain (groups of) other statements; they affect or control
+the execution of those other statements in some way. In general, compound
+statements span multiple lines, although in simple incarnations a whole compound
+statement may be contained in one line.
+
+The :keyword:`if`, :keyword:`while` and :keyword:`for` statements implement
+traditional control flow constructs. :keyword:`try` specifies exception
+handlers and/or cleanup code for a group of statements. Function and class
+definitions are also syntactically compound statements.
+
+.. index::
+ single: clause
+ single: suite
+
+Compound statements consist of one or more 'clauses.' A clause consists of a
+header and a 'suite.' The clause headers of a particular compound statement are
+all at the same indentation level. Each clause header begins with a uniquely
+identifying keyword and ends with a colon. A suite is a group of statements
+controlled by a clause. A suite can be one or more semicolon-separated simple
+statements on the same line as the header, following the header's colon, or it
+can be one or more indented statements on subsequent lines. Only the latter
+form of suite can contain nested compound statements; the following is illegal,
+mostly because it wouldn't be clear to which :keyword:`if` clause a following
+:keyword:`else` clause would belong: ::
+
+ if test1: if test2: print x
+
+Also note that the semicolon binds tighter than the colon in this context, so
+that in the following example, either all or none of the :keyword:`print`
+statements are executed::
+
+ if x < y < z: print x; print y; print z
+
+Summarizing:
+
+.. productionlist::
+ compound_stmt: `if_stmt`
+ : | `while_stmt`
+ : | `for_stmt`
+ : | `try_stmt`
+ : | `with_stmt`
+ : | `funcdef`
+ : | `classdef`
+ suite: `stmt_list` NEWLINE | NEWLINE INDENT `statement`+ DEDENT
+ statement: `stmt_list` NEWLINE | `compound_stmt`
+ stmt_list: `simple_stmt` (";" `simple_stmt`)* [";"]
+
+.. index::
+ single: NEWLINE token
+ single: DEDENT token
+ pair: dangling; else
+
+Note that statements always end in a ``NEWLINE`` possibly followed by a
+``DEDENT``. Also note that optional continuation clauses always begin with a
+keyword that cannot start a statement, thus there are no ambiguities (the
+'dangling :keyword:`else`' problem is solved in Python by requiring nested
+:keyword:`if` statements to be indented).
+
+The formatting of the grammar rules in the following sections places each clause
+on a separate line for clarity.
+
+
+.. _if:
+
+The :keyword:`if` statement
+===========================
+
+.. index:: statement: if
+
+The :keyword:`if` statement is used for conditional execution:
+
+.. productionlist::
+ if_stmt: "if" `expression` ":" `suite`
+ : ( "elif" `expression` ":" `suite` )*
+ : ["else" ":" `suite`]
+
+.. index::
+ keyword: elif
+ keyword: else
+
+It selects exactly one of the suites by evaluating the expressions one by one
+until one is found to be true (see section :ref:`booleans` for the definition of
+true and false); then that suite is executed (and no other part of the
+:keyword:`if` statement is executed or evaluated). If all expressions are
+false, the suite of the :keyword:`else` clause, if present, is executed.
+
+
+.. _while:
+
+The :keyword:`while` statement
+==============================
+
+.. index::
+ statement: while
+ pair: loop; statement
+
+The :keyword:`while` statement is used for repeated execution as long as an
+expression is true:
+
+.. productionlist::
+ while_stmt: "while" `expression` ":" `suite`
+ : ["else" ":" `suite`]
+
+.. index:: keyword: else
+
+This repeatedly tests the expression and, if it is true, executes the first
+suite; if the expression is false (which may be the first time it is tested) the
+suite of the :keyword:`else` clause, if present, is executed and the loop
+terminates.
+
+.. index::
+ statement: break
+ statement: continue
+
+A :keyword:`break` statement executed in the first suite terminates the loop
+without executing the :keyword:`else` clause's suite. A :keyword:`continue`
+statement executed in the first suite skips the rest of the suite and goes back
+to testing the expression.
+
+
+.. _for:
+
+The :keyword:`for` statement
+============================
+
+.. index::
+ statement: for
+ pair: loop; statement
+
+.. index:: object: sequence
+
+The :keyword:`for` statement is used to iterate over the elements of a sequence
+(such as a string, tuple or list) or other iterable object:
+
+.. productionlist::
+ for_stmt: "for" `target_list` "in" `expression_list` ":" `suite`
+ : ["else" ":" `suite`]
+
+.. index::
+ keyword: in
+ keyword: else
+ pair: target; list
+
+The expression list is evaluated once; it should yield an iterable object. An
+iterator is created for the result of the ``expression_list``. The suite is
+then executed once for each item provided by the iterator, in the order of
+ascending indices. Each item in turn is assigned to the target list using the
+standard rules for assignments, and then the suite is executed. When the items
+are exhausted (which is immediately when the sequence is empty), the suite in
+the :keyword:`else` clause, if present, is executed, and the loop terminates.
+
+.. index::
+ statement: break
+ statement: continue
+
+A :keyword:`break` statement executed in the first suite terminates the loop
+without executing the :keyword:`else` clause's suite. A :keyword:`continue`
+statement executed in the first suite skips the rest of the suite and continues
+with the next item, or with the :keyword:`else` clause if there was no next
+item.
+
+The suite may assign to the variable(s) in the target list; this does not affect
+the next item assigned to it.
+
+.. index::
+ builtin: range
+ pair: Pascal; language
+
+The target list is not deleted when the loop is finished, but if the sequence is
+empty, it will not have been assigned to at all by the loop. Hint: the built-in
+function :func:`range` returns a sequence of integers suitable to emulate the
+effect of Pascal's ``for i := a to b do``; e.g., ``range(3)`` returns the list
+``[0, 1, 2]``.
+
+.. warning::
+
+ .. index::
+ single: loop; over mutable sequence
+ single: mutable sequence; loop over
+
+ There is a subtlety when the sequence is being modified by the loop (this can
+ only occur for mutable sequences, i.e. lists). An internal counter is used to
+ keep track of which item is used next, and this is incremented on each
+ iteration. When this counter has reached the length of the sequence the loop
+ terminates. This means that if the suite deletes the current (or a previous)
+ item from the sequence, the next item will be skipped (since it gets the index
+ of the current item which has already been treated). Likewise, if the suite
+ inserts an item in the sequence before the current item, the current item will
+ be treated again the next time through the loop. This can lead to nasty bugs
+ that can be avoided by making a temporary copy using a slice of the whole
+ sequence, e.g.,
+
+::
+
+ for x in a[:]:
+ if x < 0: a.remove(x)
+
+
+.. _try:
+
+The :keyword:`try` statement
+============================
+
+.. index:: statement: try
+
+The :keyword:`try` statement specifies exception handlers and/or cleanup code
+for a group of statements:
+
+.. productionlist::
+ try_stmt: try1_stmt | try2_stmt
+ try1_stmt: "try" ":" `suite`
+ : ("except" [`expression` ["," `target`]] ":" `suite`)+
+ : ["else" ":" `suite`]
+ : ["finally" ":" `suite`]
+ try2_stmt: "try" ":" `suite`
+ : "finally" ":" `suite`
+
+.. versionchanged:: 2.5
+ In previous versions of Python, :keyword:`try`...\ :keyword:`except`...\
+ :keyword:`finally` did not work. :keyword:`try`...\ :keyword:`except` had to be
+ nested in :keyword:`try`...\ :keyword:`finally`.
+
+.. index:: keyword: except
+
+The :keyword:`except` clause(s) specify one or more exception handlers. When no
+exception occurs in the :keyword:`try` clause, no exception handler is executed.
+When an exception occurs in the :keyword:`try` suite, a search for an exception
+handler is started. This search inspects the except clauses in turn until one
+is found that matches the exception. An expression-less except clause, if
+present, must be last; it matches any exception. For an except clause with an
+expression, that expression is evaluated, and the clause matches the exception
+if the resulting object is "compatible" with the exception. An object is
+compatible with an exception if it is the class or a base class of the exception
+object or a tuple containing an item compatible with the exception.
+
+If no except clause matches the exception, the search for an exception handler
+continues in the surrounding code and on the invocation stack. [#]_
+
+If the evaluation of an expression in the header of an except clause raises an
+exception, the original search for a handler is canceled and a search starts for
+the new exception in the surrounding code and on the call stack (it is treated
+as if the entire :keyword:`try` statement raised the exception).
+
+When a matching except clause is found, the exception is assigned to the target
+specified in that except clause, if present, and the except clause's suite is
+executed. All except clauses must have an executable block. When the end of
+this block is reached, execution continues normally after the entire try
+statement. (This means that if two nested handlers exist for the same
+exception, and the exception occurs in the try clause of the inner handler, the
+outer handler will not handle the exception.)
+
+.. index::
+ module: sys
+ object: traceback
+
+Before an except clause's suite is executed, details about the exception are
+stored in the :mod:`sys` module and can be access via :func:`sys.exc_info`.
+:func:`sys.exc_info` returns a 3-tuple consisting of: ``exc_type`` receives the
+object identifying the exception; ``exc_value`` receives the exception's
+parameter; ``exc_traceback`` receives a traceback object (see section
+:ref:`types`) identifying the point in the program where the exception
+occurred. :func:`sys.exc_info` values are restored to their previous values
+(before the call) when returning from a function that handled an exception.
+
+.. index::
+ keyword: else
+ statement: return
+ statement: break
+ statement: continue
+
+The optional :keyword:`else` clause is executed if and when control flows off
+the end of the :keyword:`try` clause. [#]_ Exceptions in the :keyword:`else`
+clause are not handled by the preceding :keyword:`except` clauses.
+
+.. index:: keyword: finally
+
+If :keyword:`finally` is present, it specifies a 'cleanup' handler. The
+:keyword:`try` clause is executed, including any :keyword:`except` and
+:keyword:`else` clauses. If an exception occurs in any of the clauses and is
+not handled, the exception is temporarily saved. The :keyword:`finally` clause
+is executed. If there is a saved exception, it is re-raised at the end of the
+:keyword:`finally` clause. If the :keyword:`finally` clause raises another
+exception or executes a :keyword:`return` or :keyword:`break` statement, the
+saved exception is lost. The exception information is not available to the
+program during execution of the :keyword:`finally` clause.
+
+.. index::
+ statement: return
+ statement: break
+ statement: continue
+
+When a :keyword:`return`, :keyword:`break` or :keyword:`continue` statement is
+executed in the :keyword:`try` suite of a :keyword:`try`...\ :keyword:`finally`
+statement, the :keyword:`finally` clause is also executed 'on the way out.' A
+:keyword:`continue` statement is illegal in the :keyword:`finally` clause. (The
+reason is a problem with the current implementation --- this restriction may be
+lifted in the future).
+
+Additional information on exceptions can be found in section :ref:`exceptions`,
+and information on using the :keyword:`raise` statement to generate exceptions
+may be found in section :ref:`raise`.
+
+
+.. _with:
+
+The :keyword:`with` statement
+=============================
+
+.. index:: statement: with
+
+.. versionadded:: 2.5
+
+The :keyword:`with` statement is used to wrap the execution of a block with
+methods defined by a context manager (see section :ref:`context-managers`). This
+allows common :keyword:`try`...\ :keyword:`except`...\ :keyword:`finally` usage
+patterns to be encapsulated for convenient reuse.
+
+.. productionlist::
+ with_stmt: "with" `expression` ["as" `target`] ":" `suite`
+
+The execution of the :keyword:`with` statement proceeds as follows:
+
+#. The context expression is evaluated to obtain a context manager.
+
+#. The context manager's :meth:`__enter__` method is invoked.
+
+#. If a target was included in the :keyword:`with` statement, the return value
+ from :meth:`__enter__` is assigned to it.
+
+ .. note::
+
+ The :keyword:`with` statement guarantees that if the :meth:`__enter__` method
+ returns without an error, then :meth:`__exit__` will always be called. Thus, if
+ an error occurs during the assignment to the target list, it will be treated the
+ same as an error occurring within the suite would be. See step 5 below.
+
+#. The suite is executed.
+
+#. The context manager's :meth:`__exit__` method is invoked. If an exception
+ caused the suite to be exited, its type, value, and traceback are passed as
+ arguments to :meth:`__exit__`. Otherwise, three :const:`None` arguments are
+ supplied.
+
+ If the suite was exited due to an exception, and the return value from the
+ :meth:`__exit__` method was false, the exception is reraised. If the return
+ value was true, the exception is suppressed, and execution continues with the
+ statement following the :keyword:`with` statement.
+
+ If the suite was exited for any reason other than an exception, the return value
+ from :meth:`__exit__` is ignored, and execution proceeds at the normal location
+ for the kind of exit that was taken.
+
+.. note::
+
+ In Python 2.5, the :keyword:`with` statement is only allowed when the
+ ``with_statement`` feature has been enabled. It will always be enabled in
+ Python 2.6. This ``__future__`` import statement can be used to enable the
+ feature::
+
+ from __future__ import with_statement
+
+
+.. seealso::
+
+ :pep:`0343` - The "with" statement
+ The specification, background, and examples for the Python :keyword:`with`
+ statement.
+
+
+.. _function:
+
+Function definitions
+====================
+
+.. index::
+ pair: function; definition
+ statement: def
+
+.. index::
+ object: user-defined function
+ object: function
+
+A function definition defines a user-defined function object (see section
+:ref:`types`):
+
+.. productionlist::
+ funcdef: [`decorators`] "def" `funcname` "(" [`parameter_list`] ")" ["->" `expression`]? ":" `suite`
+ decorators: `decorator`+
+ decorator: "@" `dotted_name` ["(" [`argument_list` [","]] ")"] NEWLINE
+ dotted_name: `identifier` ("." `identifier`)*
+ parameter_list: (`defparameter` ",")*
+ : ( "*" [`parameter`] ("," `defparameter`)*
+ : [, "**" `parameter`]
+ : | "**" `parameter`
+ : | `defparameter` [","] )
+ parameter: `identifier` [":" `expression`]
+ defparameter: `parameter` ["=" `expression`]
+ funcname: `identifier`
+
+.. index::
+ pair: function; name
+ pair: name; binding
+
+A function definition is an executable statement. Its execution binds the
+function name in the current local namespace to a function object (a wrapper
+around the executable code for the function). This function object contains a
+reference to the current global namespace as the global namespace to be used
+when the function is called.
+
+The function definition does not execute the function body; this gets executed
+only when the function is called.
+
+A function definition may be wrapped by one or more decorator expressions.
+Decorator expressions are evaluated when the function is defined, in the scope
+that contains the function definition. The result must be a callable, which is
+invoked with the function object as the only argument. The returned value is
+bound to the function name instead of the function object. Multiple decorators
+are applied in nested fashion. For example, the following code::
+
+ @f1(arg)
+ @f2
+ def func(): pass
+
+is equivalent to::
+
+ def func(): pass
+ func = f1(arg)(f2(func))
+
+.. index:: triple: default; parameter; value
+
+When one or more parameters have the form *parameter* ``=`` *expression*, the
+function is said to have "default parameter values." For a parameter with a
+default value, the corresponding argument may be omitted from a call, in which
+case the parameter's default value is substituted. If a parameter has a default
+value, all following parameters up until the "``*``" must also have a default
+value --- this is a syntactic restriction that is not expressed by the grammar.
+
+**Default parameter values are evaluated when the function definition is
+executed.** This means that the expression is evaluated once, when the function
+is defined, and that that same "pre-computed" value is used for each call. This
+is especially important to understand when a default parameter is a mutable
+object, such as a list or a dictionary: if the function modifies the object
+(e.g. by appending an item to a list), the default value is in effect modified.
+This is generally not what was intended. A way around this is to use ``None``
+as the default, and explicitly test for it in the body of the function, e.g.::
+
+ def whats_on_the_telly(penguin=None):
+ if penguin is None:
+ penguin = []
+ penguin.append("property of the zoo")
+ return penguin
+
+Function call semantics are described in more detail in section :ref:`calls`. A
+function call always assigns values to all parameters mentioned in the parameter
+list, either from position arguments, from keyword arguments, or from default
+values. If the form "``*identifier``" is present, it is initialized to a tuple
+receiving any excess positional parameters, defaulting to the empty tuple. If
+the form "``**identifier``" is present, it is initialized to a new dictionary
+receiving any excess keyword arguments, defaulting to a new empty dictionary.
+Parameters after "``*``" or "``*identifier``" are keyword-only parameters and
+may only be passed used keyword arguments.
+
+.. index:: pair: function; annotations
+
+Parameters may have annotations of the form "``: expression``" following the
+parameter name. Any parameter may have an annotation even those of the form
+``*identifier`` or ``**identifier``. Functions may have "return" annotation of
+the form "``-> expression``" after the parameter list. These annotations can be
+any valid Python expression and are evaluated when the function definition is
+executed. Annotations may be evaluated in a different order than they appear in
+the source code. The presence of annotations does not change the semantics of a
+function. The annotation values are available as values of a dictionary keyed
+by the parameters' names in the :attr:`__annotations__` attribute of the
+function object.
+
+.. index:: pair: lambda; form
+
+It is also possible to create anonymous functions (functions not bound to a
+name), for immediate use in expressions. This uses lambda forms, described in
+section :ref:`lambda`. Note that the lambda form is merely a shorthand for a
+simplified function definition; a function defined in a ":keyword:`def`"
+statement can be passed around or assigned to another name just like a function
+defined by a lambda form. The ":keyword:`def`" form is actually more powerful
+since it allows the execution of multiple statements and annotations.
+
+**Programmer's note:** Functions are first-class objects. A "``def``" form
+executed inside a function definition defines a local function that can be
+returned or passed around. Free variables used in the nested function can
+access the local variables of the function containing the def. See section
+:ref:`naming` for details.
+
+
+.. _class:
+
+Class definitions
+=================
+
+.. index::
+ pair: class; definition
+ statement: class
+
+.. index:: object: class
+
+A class definition defines a class object (see section :ref:`types`):
+
+.. productionlist::
+ classdef: "class" `classname` [`inheritance`] ":" `suite`
+ inheritance: "(" [`expression_list`] ")"
+ classname: `identifier`
+
+.. index::
+ single: inheritance
+ pair: class; name
+ pair: name; binding
+ pair: execution; frame
+
+A class definition is an executable statement. It first evaluates the
+inheritance list, if present. Each item in the inheritance list should evaluate
+to a class object or class type which allows subclassing. The class's suite is
+then executed in a new execution frame (see section :ref:`naming`), using a
+newly created local namespace and the original global namespace. (Usually, the
+suite contains only function definitions.) When the class's suite finishes
+execution, its execution frame is discarded but its local namespace is saved. A
+class object is then created using the inheritance list for the base classes and
+the saved local namespace for the attribute dictionary. The class name is bound
+to this class object in the original local namespace.
+
+**Programmer's note:** Variables defined in the class definition are class
+variables; they are shared by all instances. To define instance variables, they
+must be given a value in the :meth:`__init__` method or in another method. Both
+class and instance variables are accessible through the notation
+"``self.name``", and an instance variable hides a class variable with the same
+name when accessed in this way. Class variables with immutable values can be
+used as defaults for instance variables. For new-style classes, descriptors can
+be used to create instance variables with different implementation details.
+
+.. rubric:: Footnotes
+
+.. [#] The exception is propogated to the invocation stack only if there is no
+ :keyword:`finally` clause that negates the exception.
+
+.. [#] Currently, control "flows off the end" except in the case of an exception or the
+ execution of a :keyword:`return`, :keyword:`continue`, or :keyword:`break`
+ statement.
+
diff --git a/Doc/reference/datamodel.rst b/Doc/reference/datamodel.rst
new file mode 100644
index 0000000000..2f6013e48e
--- /dev/null
+++ b/Doc/reference/datamodel.rst
@@ -0,0 +1,2118 @@
+
+.. _datamodel:
+
+**********
+Data model
+**********
+
+
+.. _objects:
+
+Objects, values and types
+=========================
+
+.. index::
+ single: object
+ single: data
+
+:dfn:`Objects` are Python's abstraction for data. All data in a Python program
+is represented by objects or by relations between objects. (In a sense, and in
+conformance to Von Neumann's model of a "stored program computer," code is also
+represented by objects.)
+
+.. index::
+ builtin: id
+ builtin: type
+ single: identity of an object
+ single: value of an object
+ single: type of an object
+ single: mutable object
+ single: immutable object
+
+Every object has an identity, a type and a value. An object's *identity* never
+changes once it has been created; you may think of it as the object's address in
+memory. The ':keyword:`is`' operator compares the identity of two objects; the
+:func:`id` function returns an integer representing its identity (currently
+implemented as its address). An object's :dfn:`type` is also unchangeable. [#]_
+An object's type determines the operations that the object supports (e.g., "does
+it have a length?") and also defines the possible values for objects of that
+type. The :func:`type` function returns an object's type (which is an object
+itself). The *value* of some objects can change. Objects whose value can
+change are said to be *mutable*; objects whose value is unchangeable once they
+are created are called *immutable*. (The value of an immutable container object
+that contains a reference to a mutable object can change when the latter's value
+is changed; however the container is still considered immutable, because the
+collection of objects it contains cannot be changed. So, immutability is not
+strictly the same as having an unchangeable value, it is more subtle.) An
+object's mutability is determined by its type; for instance, numbers, strings
+and tuples are immutable, while dictionaries and lists are mutable.
+
+.. index::
+ single: garbage collection
+ single: reference counting
+ single: unreachable object
+
+Objects are never explicitly destroyed; however, when they become unreachable
+they may be garbage-collected. An implementation is allowed to postpone garbage
+collection or omit it altogether --- it is a matter of implementation quality
+how garbage collection is implemented, as long as no objects are collected that
+are still reachable. (Implementation note: the current implementation uses a
+reference-counting scheme with (optional) delayed detection of cyclically linked
+garbage, which collects most objects as soon as they become unreachable, but is
+not guaranteed to collect garbage containing circular references. See the
+documentation of the :mod:`gc` module for information on controlling the
+collection of cyclic garbage.)
+
+Note that the use of the implementation's tracing or debugging facilities may
+keep objects alive that would normally be collectable. Also note that catching
+an exception with a ':keyword:`try`...\ :keyword:`except`' statement may keep
+objects alive.
+
+Some objects contain references to "external" resources such as open files or
+windows. It is understood that these resources are freed when the object is
+garbage-collected, but since garbage collection is not guaranteed to happen,
+such objects also provide an explicit way to release the external resource,
+usually a :meth:`close` method. Programs are strongly recommended to explicitly
+close such objects. The ':keyword:`try`...\ :keyword:`finally`' statement
+provides a convenient way to do this.
+
+.. index:: single: container
+
+Some objects contain references to other objects; these are called *containers*.
+Examples of containers are tuples, lists and dictionaries. The references are
+part of a container's value. In most cases, when we talk about the value of a
+container, we imply the values, not the identities of the contained objects;
+however, when we talk about the mutability of a container, only the identities
+of the immediately contained objects are implied. So, if an immutable container
+(like a tuple) contains a reference to a mutable object, its value changes if
+that mutable object is changed.
+
+Types affect almost all aspects of object behavior. Even the importance of
+object identity is affected in some sense: for immutable types, operations that
+compute new values may actually return a reference to any existing object with
+the same type and value, while for mutable objects this is not allowed. E.g.,
+after ``a = 1; b = 1``, ``a`` and ``b`` may or may not refer to the same object
+with the value one, depending on the implementation, but after ``c = []; d =
+[]``, ``c`` and ``d`` are guaranteed to refer to two different, unique, newly
+created empty lists. (Note that ``c = d = []`` assigns the same object to both
+``c`` and ``d``.)
+
+
+.. _types:
+
+The standard type hierarchy
+===========================
+
+.. index::
+ single: type
+ pair: data; type
+ pair: type; hierarchy
+ pair: extension; module
+ pair: C; language
+
+Below is a list of the types that are built into Python. Extension modules
+(written in C, Java, or other languages, depending on the implementation) can
+define additional types. Future versions of Python may add types to the type
+hierarchy (e.g., rational numbers, efficiently stored arrays of integers, etc.).
+
+.. index::
+ single: attribute
+ pair: special; attribute
+ triple: generic; special; attribute
+
+Some of the type descriptions below contain a paragraph listing 'special
+attributes.' These are attributes that provide access to the implementation and
+are not intended for general use. Their definition may change in the future.
+
+None
+ .. index:: object: None
+
+ This type has a single value. There is a single object with this value. This
+ object is accessed through the built-in name ``None``. It is used to signify the
+ absence of a value in many situations, e.g., it is returned from functions that
+ don't explicitly return anything. Its truth value is false.
+
+NotImplemented
+ .. index:: object: NotImplemented
+
+ This type has a single value. There is a single object with this value. This
+ object is accessed through the built-in name ``NotImplemented``. Numeric methods
+ and rich comparison methods may return this value if they do not implement the
+ operation for the operands provided. (The interpreter will then try the
+ reflected operation, or some other fallback, depending on the operator.) Its
+ truth value is true.
+
+Ellipsis
+ .. index:: object: Ellipsis
+
+ This type has a single value. There is a single object with this value. This
+ object is accessed through the literal ``...`` or the built-in name
+ ``Ellipsis``. Its truth value is true.
+
+Numbers
+ .. index:: object: numeric
+
+ These are created by numeric literals and returned as results by arithmetic
+ operators and arithmetic built-in functions. Numeric objects are immutable;
+ once created their value never changes. Python numbers are of course strongly
+ related to mathematical numbers, but subject to the limitations of numerical
+ representation in computers.
+
+ Python distinguishes between integers, floating point numbers, and complex
+ numbers:
+
+ Integers
+ .. index:: object: integer
+
+ These represent elements from the mathematical set of integers (positive and
+ negative).
+
+ There are three types of integers:
+
+ Plain integers
+ .. index::
+ object: plain integer
+ single: OverflowError (built-in exception)
+
+ These represent numbers in the range -2147483648 through 2147483647. (The range
+ may be larger on machines with a larger natural word size, but not smaller.)
+ When the result of an operation would fall outside this range, the result is
+ normally returned as a long integer (in some cases, the exception
+ :exc:`OverflowError` is raised instead). For the purpose of shift and mask
+ operations, integers are assumed to have a binary, 2's complement notation using
+ 32 or more bits, and hiding no bits from the user (i.e., all 4294967296
+ different bit patterns correspond to different values).
+
+ Long integers
+ .. index:: object: long integer
+
+ These represent numbers in an unlimited range, subject to available (virtual)
+ memory only. For the purpose of shift and mask operations, a binary
+ representation is assumed, and negative numbers are represented in a variant of
+ 2's complement which gives the illusion of an infinite string of sign bits
+ extending to the left.
+
+ Booleans
+ .. index::
+ object: Boolean
+ single: False
+ single: True
+
+ These represent the truth values False and True. The two objects representing
+ the values False and True are the only Boolean objects. The Boolean type is a
+ subtype of plain integers, and Boolean values behave like the values 0 and 1,
+ respectively, in almost all contexts, the exception being that when converted to
+ a string, the strings ``"False"`` or ``"True"`` are returned, respectively.
+
+ .. index:: pair: integer; representation
+
+ The rules for integer representation are intended to give the most meaningful
+ interpretation of shift and mask operations involving negative integers and the
+ least surprises when switching between the plain and long integer domains. Any
+ operation except left shift, if it yields a result in the plain integer domain
+ without causing overflow, will yield the same result in the long integer domain
+ or when using mixed operands.
+
+ .. % Integers
+
+ Floating point numbers
+ .. index::
+ object: floating point
+ pair: floating point; number
+ pair: C; language
+ pair: Java; language
+
+ These represent machine-level double precision floating point numbers. You are
+ at the mercy of the underlying machine architecture (and C or Java
+ implementation) for the accepted range and handling of overflow. Python does not
+ support single-precision floating point numbers; the savings in processor and
+ memory usage that are usually the reason for using these is dwarfed by the
+ overhead of using objects in Python, so there is no reason to complicate the
+ language with two kinds of floating point numbers.
+
+ Complex numbers
+ .. index::
+ object: complex
+ pair: complex; number
+
+ These represent complex numbers as a pair of machine-level double precision
+ floating point numbers. The same caveats apply as for floating point numbers.
+ The real and imaginary parts of a complex number ``z`` can be retrieved through
+ the read-only attributes ``z.real`` and ``z.imag``.
+
+ .. % Numbers
+
+Sequences
+ .. index::
+ builtin: len
+ object: sequence
+ single: index operation
+ single: item selection
+ single: subscription
+
+ These represent finite ordered sets indexed by non-negative numbers. The
+ built-in function :func:`len` returns the number of items of a sequence. When
+ the length of a sequence is *n*, the index set contains the numbers 0, 1,
+ ..., *n*-1. Item *i* of sequence *a* is selected by ``a[i]``.
+
+ .. index:: single: slicing
+
+ Sequences also support slicing: ``a[i:j]`` selects all items with index *k* such
+ that *i* ``<=`` *k* ``<`` *j*. When used as an expression, a slice is a
+ sequence of the same type. This implies that the index set is renumbered so
+ that it starts at 0.
+
+ .. index:: single: extended slicing
+
+ Some sequences also support "extended slicing" with a third "step" parameter:
+ ``a[i:j:k]`` selects all items of *a* with index *x* where ``x = i + n*k``, *n*
+ ``>=`` ``0`` and *i* ``<=`` *x* ``<`` *j*.
+
+ Sequences are distinguished according to their mutability:
+
+ Immutable sequences
+ .. index::
+ object: immutable sequence
+ object: immutable
+
+ An object of an immutable sequence type cannot change once it is created. (If
+ the object contains references to other objects, these other objects may be
+ mutable and may be changed; however, the collection of objects directly
+ referenced by an immutable object cannot change.)
+
+ The following types are immutable sequences:
+
+ Strings
+ .. index::
+ builtin: chr
+ builtin: ord
+ object: string
+ single: character
+ single: byte
+ single: ASCII@ASCII
+
+ The items of a string are characters. There is no separate character type; a
+ character is represented by a string of one item. Characters represent (at
+ least) 8-bit bytes. The built-in functions :func:`chr` and :func:`ord` convert
+ between characters and nonnegative integers representing the byte values. Bytes
+ with the values 0-127 usually represent the corresponding ASCII values, but the
+ interpretation of values is up to the program. The string data type is also
+ used to represent arrays of bytes, e.g., to hold data read from a file.
+
+ .. index::
+ single: ASCII@ASCII
+ single: EBCDIC
+ single: character set
+ pair: string; comparison
+ builtin: chr
+ builtin: ord
+
+ (On systems whose native character set is not ASCII, strings may use EBCDIC in
+ their internal representation, provided the functions :func:`chr` and
+ :func:`ord` implement a mapping between ASCII and EBCDIC, and string comparison
+ preserves the ASCII order. Or perhaps someone can propose a better rule?)
+
+ Unicode
+ .. index::
+ builtin: unichr
+ builtin: ord
+ builtin: unicode
+ object: unicode
+ single: character
+ single: integer
+ single: Unicode
+
+ The items of a Unicode object are Unicode code units. A Unicode code unit is
+ represented by a Unicode object of one item and can hold either a 16-bit or
+ 32-bit value representing a Unicode ordinal (the maximum value for the ordinal
+ is given in ``sys.maxunicode``, and depends on how Python is configured at
+ compile time). Surrogate pairs may be present in the Unicode object, and will
+ be reported as two separate items. The built-in functions :func:`unichr` and
+ :func:`ord` convert between code units and nonnegative integers representing the
+ Unicode ordinals as defined in the Unicode Standard 3.0. Conversion from and to
+ other encodings are possible through the Unicode method :meth:`encode` and the
+ built-in function :func:`unicode`.
+
+ Tuples
+ .. index::
+ object: tuple
+ pair: singleton; tuple
+ pair: empty; tuple
+
+ The items of a tuple are arbitrary Python objects. Tuples of two or more items
+ are formed by comma-separated lists of expressions. A tuple of one item (a
+ 'singleton') can be formed by affixing a comma to an expression (an expression
+ by itself does not create a tuple, since parentheses must be usable for grouping
+ of expressions). An empty tuple can be formed by an empty pair of parentheses.
+
+ .. % Immutable sequences
+
+ Mutable sequences
+ .. index::
+ object: mutable sequence
+ object: mutable
+ pair: assignment; statement
+ single: delete
+ statement: del
+ single: subscription
+ single: slicing
+
+ Mutable sequences can be changed after they are created. The subscription and
+ slicing notations can be used as the target of assignment and :keyword:`del`
+ (delete) statements.
+
+ There is currently a single intrinsic mutable sequence type:
+
+ Lists
+ .. index:: object: list
+
+ The items of a list are arbitrary Python objects. Lists are formed by placing a
+ comma-separated list of expressions in square brackets. (Note that there are no
+ special cases needed to form lists of length 0 or 1.)
+
+ .. index:: module: array
+
+ The extension module :mod:`array` provides an additional example of a mutable
+ sequence type.
+
+ .. % Mutable sequences
+
+ .. % Sequences
+
+Set types
+ .. index::
+ builtin: len
+ object: set type
+
+ These represent unordered, finite sets of unique, immutable objects. As such,
+ they cannot be indexed by any subscript. However, they can be iterated over, and
+ the built-in function :func:`len` returns the number of items in a set. Common
+ uses for sets are fast membership testing, removing duplicates from a sequence,
+ and computing mathematical operations such as intersection, union, difference,
+ and symmetric difference.
+
+ For set elements, the same immutability rules apply as for dictionary keys. Note
+ that numeric types obey the normal rules for numeric comparison: if two numbers
+ compare equal (e.g., ``1`` and ``1.0``), only one of them can be contained in a
+ set.
+
+ There are currently two intrinsic set types:
+
+ Sets
+ .. index:: object: set
+
+ These represent a mutable set. They are created by the built-in :func:`set`
+ constructor and can be modified afterwards by several methods, such as
+ :meth:`add`.
+
+ Frozen sets
+ .. index:: object: frozenset
+
+ These represent an immutable set. They are created by the built-in
+ :func:`frozenset` constructor. As a frozenset is immutable and hashable, it can
+ be used again as an element of another set, or as a dictionary key.
+
+ .. % Set types
+
+Mappings
+ .. index::
+ builtin: len
+ single: subscription
+ object: mapping
+
+ These represent finite sets of objects indexed by arbitrary index sets. The
+ subscript notation ``a[k]`` selects the item indexed by ``k`` from the mapping
+ ``a``; this can be used in expressions and as the target of assignments or
+ :keyword:`del` statements. The built-in function :func:`len` returns the number
+ of items in a mapping.
+
+ There is currently a single intrinsic mapping type:
+
+ Dictionaries
+ .. index:: object: dictionary
+
+ These represent finite sets of objects indexed by nearly arbitrary values. The
+ only types of values not acceptable as keys are values containing lists or
+ dictionaries or other mutable types that are compared by value rather than by
+ object identity, the reason being that the efficient implementation of
+ dictionaries requires a key's hash value to remain constant. Numeric types used
+ for keys obey the normal rules for numeric comparison: if two numbers compare
+ equal (e.g., ``1`` and ``1.0``) then they can be used interchangeably to index
+ the same dictionary entry.
+
+ Dictionaries are mutable; they can be created by the ``{...}`` notation (see
+ section :ref:`dict`).
+
+ .. index::
+ module: dbm
+ module: gdbm
+ module: bsddb
+
+ The extension modules :mod:`dbm`, :mod:`gdbm`, and :mod:`bsddb` provide
+ additional examples of mapping types.
+
+ .. % Mapping types
+
+Callable types
+ .. index::
+ object: callable
+ pair: function; call
+ single: invocation
+ pair: function; argument
+
+ These are the types to which the function call operation (see section
+ :ref:`calls`) can be applied:
+
+ User-defined functions
+ .. index::
+ pair: user-defined; function
+ object: function
+ object: user-defined function
+
+ A user-defined function object is created by a function definition (see
+ section :ref:`function`). It should be called with an argument list
+ containing the same number of items as the function's formal parameter
+ list.
+
+ Special attributes:
+
+ +-------------------------+-------------------------------+-----------+
+ | Attribute | Meaning | |
+ +=========================+===============================+===========+
+ | :attr:`__doc__` | The function's documentation | Writable |
+ | | string, or ``None`` if | |
+ | | unavailable | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__name__` | The function's name | Writable |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__module__` | The name of the module the | Writable |
+ | | function was defined in, or | |
+ | | ``None`` if unavailable. | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__defaults__` | A tuple containing default | Writable |
+ | | argument values for those | |
+ | | arguments that have defaults, | |
+ | | or ``None`` if no arguments | |
+ | | have a default value | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__code__` | The code object representing | Writable |
+ | | the compiled function body. | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__globals__` | A reference to the dictionary | Read-only |
+ | | that holds the function's | |
+ | | global variables --- the | |
+ | | global namespace of the | |
+ | | module in which the function | |
+ | | was defined. | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__dict__` | The namespace supporting | Writable |
+ | | arbitrary function | |
+ | | attributes. | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__closure__` | ``None`` or a tuple of cells | Read-only |
+ | | that contain bindings for the | |
+ | | function's free variables. | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__annotations__` | A dict containing annotations | Writable |
+ | | of parameters. The keys of | |
+ | | the dict are the parameter | |
+ | | names, or ``'return'`` for | |
+ | | the return annotation, if | |
+ | | provided. | |
+ +-------------------------+-------------------------------+-----------+
+ | :attr:`__kwdefaults__` | A dict containing defaults | Writable |
+ | | for keyword-only parameters. | |
+ +-------------------------+-------------------------------+-----------+
+
+ Most of the attributes labelled "Writable" check the type of the assigned value.
+
+ .. versionchanged:: 2.4
+ ``__name__`` is now writable.
+
+ Function objects also support getting and setting arbitrary attributes, which
+ can be used, for example, to attach metadata to functions. Regular attribute
+ dot-notation is used to get and set such attributes. *Note that the current
+ implementation only supports function attributes on user-defined functions.
+ Function attributes on built-in functions may be supported in the future.*
+
+ Additional information about a function's definition can be retrieved from its
+ code object; see the description of internal types below.
+
+ .. index::
+ single: __doc__ (function attribute)
+ single: __name__ (function attribute)
+ single: __module__ (function attribute)
+ single: __dict__ (function attribute)
+ single: __defaults__ (function attribute)
+ single: __closure__ (function attribute)
+ single: __code__ (function attribute)
+ single: __globals__ (function attribute)
+ single: __annotations__ (function attribute)
+ single: __kwdefaults__ (function attribute)
+ pair: global; namespace
+
+ User-defined methods
+ .. index::
+ object: method
+ object: user-defined method
+ pair: user-defined; method
+
+ A user-defined method object combines a class, a class instance (or ``None``)
+ and any callable object (normally a user-defined function).
+
+ Special read-only attributes: :attr:`im_self` is the class instance object,
+ :attr:`im_func` is the function object; :attr:`im_class` is the class of
+ :attr:`im_self` for bound methods or the class that asked for the method for
+ unbound methods; :attr:`__doc__` is the method's documentation (same as
+ ``im_func.__doc__``); :attr:`__name__` is the method name (same as
+ ``im_func.__name__``); :attr:`__module__` is the name of the module the method
+ was defined in, or ``None`` if unavailable.
+
+ .. versionchanged:: 2.2
+ :attr:`im_self` used to refer to the class that defined the method.
+
+ .. index::
+ single: __doc__ (method attribute)
+ single: __name__ (method attribute)
+ single: __module__ (method attribute)
+ single: im_func (method attribute)
+ single: im_self (method attribute)
+
+ Methods also support accessing (but not setting) the arbitrary function
+ attributes on the underlying function object.
+
+ User-defined method objects may be created when getting an attribute of a class
+ (perhaps via an instance of that class), if that attribute is a user-defined
+ function object, an unbound user-defined method object, or a class method
+ object. When the attribute is a user-defined method object, a new method object
+ is only created if the class from which it is being retrieved is the same as, or
+ a derived class of, the class stored in the original method object; otherwise,
+ the original method object is used as it is.
+
+ .. index::
+ single: im_class (method attribute)
+ single: im_func (method attribute)
+ single: im_self (method attribute)
+
+ When a user-defined method object is created by retrieving a user-defined
+ function object from a class, its :attr:`im_self` attribute is ``None``
+ and the method object is said to be unbound. When one is created by
+ retrieving a user-defined function object from a class via one of its
+ instances, its :attr:`im_self` attribute is the instance, and the method
+ object is said to be bound. In either case, the new method's
+ :attr:`im_class` attribute is the class from which the retrieval takes
+ place, and its :attr:`im_func` attribute is the original function object.
+
+ .. index:: single: im_func (method attribute)
+
+ When a user-defined method object is created by retrieving another method object
+ from a class or instance, the behaviour is the same as for a function object,
+ except that the :attr:`im_func` attribute of the new instance is not the
+ original method object but its :attr:`im_func` attribute.
+
+ .. index::
+ single: im_class (method attribute)
+ single: im_func (method attribute)
+ single: im_self (method attribute)
+
+ When a user-defined method object is created by retrieving a class method object
+ from a class or instance, its :attr:`im_self` attribute is the class itself (the
+ same as the :attr:`im_class` attribute), and its :attr:`im_func` attribute is
+ the function object underlying the class method.
+
+ When an unbound user-defined method object is called, the underlying function
+ (:attr:`im_func`) is called, with the restriction that the first argument must
+ be an instance of the proper class (:attr:`im_class`) or of a derived class
+ thereof.
+
+ When a bound user-defined method object is called, the underlying function
+ (:attr:`im_func`) is called, inserting the class instance (:attr:`im_self`) in
+ front of the argument list. For instance, when :class:`C` is a class which
+ contains a definition for a function :meth:`f`, and ``x`` is an instance of
+ :class:`C`, calling ``x.f(1)`` is equivalent to calling ``C.f(x, 1)``.
+
+ When a user-defined method object is derived from a class method object, the
+ "class instance" stored in :attr:`im_self` will actually be the class itself, so
+ that calling either ``x.f(1)`` or ``C.f(1)`` is equivalent to calling ``f(C,1)``
+ where ``f`` is the underlying function.
+
+ Note that the transformation from function object to (unbound or bound) method
+ object happens each time the attribute is retrieved from the class or instance.
+ In some cases, a fruitful optimization is to assign the attribute to a local
+ variable and call that local variable. Also notice that this transformation only
+ happens for user-defined functions; other callable objects (and all non-callable
+ objects) are retrieved without transformation. It is also important to note
+ that user-defined functions which are attributes of a class instance are not
+ converted to bound methods; this *only* happens when the function is an
+ attribute of the class.
+
+ Generator functions
+ .. index::
+ single: generator; function
+ single: generator; iterator
+
+ A function or method which uses the :keyword:`yield` statement (see section
+ :ref:`yield`) is called a :dfn:`generator
+ function`. Such a function, when called, always returns an iterator object
+ which can be used to execute the body of the function: calling the iterator's
+ :meth:`__next__` method will cause the function to execute until it provides a
+ value using the :keyword:`yield` statement. When the function executes a
+ :keyword:`return` statement or falls off the end, a :exc:`StopIteration`
+ exception is raised and the iterator will have reached the end of the set of
+ values to be returned.
+
+ Built-in functions
+ .. index::
+ object: built-in function
+ object: function
+ pair: C; language
+
+ A built-in function object is a wrapper around a C function. Examples of
+ built-in functions are :func:`len` and :func:`math.sin` (:mod:`math` is a
+ standard built-in module). The number and type of the arguments are
+ determined by the C function. Special read-only attributes:
+ :attr:`__doc__` is the function's documentation string, or ``None`` if
+ unavailable; :attr:`__name__` is the function's name; :attr:`__self__` is
+ set to ``None`` (but see the next item); :attr:`__module__` is the name of
+ the module the function was defined in or ``None`` if unavailable.
+
+ Built-in methods
+ .. index::
+ object: built-in method
+ object: method
+ pair: built-in; method
+
+ This is really a different disguise of a built-in function, this time containing
+ an object passed to the C function as an implicit extra argument. An example of
+ a built-in method is ``alist.append()``, assuming *alist* is a list object. In
+ this case, the special read-only attribute :attr:`__self__` is set to the object
+ denoted by *list*.
+
+ Class Types
+ Class types, or "new-style classes," are callable. These objects normally act
+ as factories for new instances of themselves, but variations are possible for
+ class types that override :meth:`__new__`. The arguments of the call are passed
+ to :meth:`__new__` and, in the typical case, to :meth:`__init__` to initialize
+ the new instance.
+
+ Classic Classes
+ .. index::
+ single: __init__() (object method)
+ object: class
+ object: class instance
+ object: instance
+ pair: class object; call
+
+ Class objects are described below. When a class object is called, a new class
+ instance (also described below) is created and returned. This implies a call to
+ the class's :meth:`__init__` method if it has one. Any arguments are passed on
+ to the :meth:`__init__` method. If there is no :meth:`__init__` method, the
+ class must be called without arguments.
+
+ Class instances
+ Class instances are described below. Class instances are callable only when the
+ class has a :meth:`__call__` method; ``x(arguments)`` is a shorthand for
+ ``x.__call__(arguments)``.
+
+Modules
+ .. index::
+ statement: import
+ object: module
+
+ Modules are imported by the :keyword:`import` statement (see section
+ :ref:`import`). A module object has a
+ namespace implemented by a dictionary object (this is the dictionary referenced
+ by the __globals__ attribute of functions defined in the module). Attribute
+ references are translated to lookups in this dictionary, e.g., ``m.x`` is
+ equivalent to ``m.__dict__["x"]``. A module object does not contain the code
+ object used to initialize the module (since it isn't needed once the
+ initialization is done).
+
+ .. %
+
+ Attribute assignment updates the module's namespace dictionary, e.g., ``m.x =
+ 1`` is equivalent to ``m.__dict__["x"] = 1``.
+
+ .. index:: single: __dict__ (module attribute)
+
+ Special read-only attribute: :attr:`__dict__` is the module's namespace as a
+ dictionary object.
+
+ .. index::
+ single: __name__ (module attribute)
+ single: __doc__ (module attribute)
+ single: __file__ (module attribute)
+ pair: module; namespace
+
+ Predefined (writable) attributes: :attr:`__name__` is the module's name;
+ :attr:`__doc__` is the module's documentation string, or ``None`` if
+ unavailable; :attr:`__file__` is the pathname of the file from which the module
+ was loaded, if it was loaded from a file. The :attr:`__file__` attribute is not
+ present for C modules that are statically linked into the interpreter; for
+ extension modules loaded dynamically from a shared library, it is the pathname
+ of the shared library file.
+
+Classes
+ Class objects are created by class definitions (see section :ref:`class`). A
+ class has a namespace implemented by a dictionary object. Class attribute
+ references are translated to lookups in this dictionary, e.g., ``C.x`` is
+ translated to ``C.__dict__["x"]``. When the attribute name is not found
+ there, the attribute search continues in the base classes. The search is
+ depth-first, left-to-right in the order of occurrence in the base class list.
+
+ .. index::
+ object: class
+ object: class instance
+ object: instance
+ pair: class object; call
+ single: container
+ object: dictionary
+ pair: class; attribute
+
+ When a class attribute reference (for class :class:`C`, say) would yield a
+ user-defined function object or an unbound user-defined method object whose
+ associated class is either :class:`C` or one of its base classes, it is
+ transformed into an unbound user-defined method object whose :attr:`im_class`
+ attribute is :class:`C`. When it would yield a class method object, it is
+ transformed into a bound user-defined method object whose :attr:`im_class`
+ and :attr:`im_self` attributes are both :class:`C`. When it would yield a
+ static method object, it is transformed into the object wrapped by the static
+ method object. See section :ref:`descriptors` for another way in which
+ attributes retrieved from a class may differ from those actually contained in
+ its :attr:`__dict__`.
+
+ .. index:: triple: class; attribute; assignment
+
+ Class attribute assignments update the class's dictionary, never the dictionary
+ of a base class.
+
+ .. index:: pair: class object; call
+
+ A class object can be called (see above) to yield a class instance (see below).
+
+ .. index::
+ single: __name__ (class attribute)
+ single: __module__ (class attribute)
+ single: __dict__ (class attribute)
+ single: __bases__ (class attribute)
+ single: __doc__ (class attribute)
+
+ Special attributes: :attr:`__name__` is the class name; :attr:`__module__` is
+ the module name in which the class was defined; :attr:`__dict__` is the
+ dictionary containing the class's namespace; :attr:`__bases__` is a tuple
+ (possibly empty or a singleton) containing the base classes, in the order of
+ their occurrence in the base class list; :attr:`__doc__` is the class's
+ documentation string, or None if undefined.
+
+Class instances
+ .. index::
+ object: class instance
+ object: instance
+ pair: class; instance
+ pair: class instance; attribute
+
+ A class instance is created by calling a class object (see above). A class
+ instance has a namespace implemented as a dictionary which is the first place in
+ which attribute references are searched. When an attribute is not found there,
+ and the instance's class has an attribute by that name, the search continues
+ with the class attributes. If a class attribute is found that is a user-defined
+ function object or an unbound user-defined method object whose associated class
+ is the class (call it :class:`C`) of the instance for which the attribute
+ reference was initiated or one of its bases, it is transformed into a bound
+ user-defined method object whose :attr:`im_class` attribute is :class:`C` and
+ whose :attr:`im_self` attribute is the instance. Static method and class method
+ objects are also transformed, as if they had been retrieved from class
+ :class:`C`; see above under "Classes". See section :ref:`descriptors` for
+ another way in which attributes of a class retrieved via its instances may
+ differ from the objects actually stored in the class's :attr:`__dict__`. If no
+ class attribute is found, and the object's class has a :meth:`__getattr__`
+ method, that is called to satisfy the lookup.
+
+ .. index:: triple: class instance; attribute; assignment
+
+ Attribute assignments and deletions update the instance's dictionary, never a
+ class's dictionary. If the class has a :meth:`__setattr__` or
+ :meth:`__delattr__` method, this is called instead of updating the instance
+ dictionary directly.
+
+ .. index::
+ object: numeric
+ object: sequence
+ object: mapping
+
+ Class instances can pretend to be numbers, sequences, or mappings if they have
+ methods with certain special names. See section :ref:`specialnames`.
+
+ .. index::
+ single: __dict__ (instance attribute)
+ single: __class__ (instance attribute)
+
+ Special attributes: :attr:`__dict__` is the attribute dictionary;
+ :attr:`__class__` is the instance's class.
+
+Files
+ .. index::
+ object: file
+ builtin: open
+ single: popen() (in module os)
+ single: makefile() (socket method)
+ single: sys.stdin
+ single: sys.stdout
+ single: sys.stderr
+ single: stdio
+ single: stdin (in module sys)
+ single: stdout (in module sys)
+ single: stderr (in module sys)
+
+ A file object represents an open file. File objects are created by the
+ :func:`open` built-in function, and also by :func:`os.popen`,
+ :func:`os.fdopen`, and the :meth:`makefile` method of socket objects (and
+ perhaps by other functions or methods provided by extension modules). The
+ objects ``sys.stdin``, ``sys.stdout`` and ``sys.stderr`` are initialized to
+ file objects corresponding to the interpreter's standard input, output and
+ error streams. See :ref:`bltin-file-objects` for complete documentation of
+ file objects.
+
+Internal types
+ .. index::
+ single: internal type
+ single: types, internal
+
+ A few types used internally by the interpreter are exposed to the user. Their
+ definitions may change with future versions of the interpreter, but they are
+ mentioned here for completeness.
+
+ Code objects
+ .. index::
+ single: bytecode
+ object: code
+
+ Code objects represent *byte-compiled* executable Python code, or *bytecode*.
+ The difference between a code object and a function object is that the function
+ object contains an explicit reference to the function's globals (the module in
+ which it was defined), while a code object contains no context; also the default
+ argument values are stored in the function object, not in the code object
+ (because they represent values calculated at run-time). Unlike function
+ objects, code objects are immutable and contain no references (directly or
+ indirectly) to mutable objects.
+
+ Special read-only attributes: :attr:`co_name` gives the function name;
+ :attr:`co_argcount` is the number of positional arguments (including arguments
+ with default values); :attr:`co_nlocals` is the number of local variables used
+ by the function (including arguments); :attr:`co_varnames` is a tuple containing
+ the names of the local variables (starting with the argument names);
+ :attr:`co_cellvars` is a tuple containing the names of local variables that are
+ referenced by nested functions; :attr:`co_freevars` is a tuple containing the
+ names of free variables; :attr:`co_code` is a string representing the sequence
+ of bytecode instructions; :attr:`co_consts` is a tuple containing the literals
+ used by the bytecode; :attr:`co_names` is a tuple containing the names used by
+ the bytecode; :attr:`co_filename` is the filename from which the code was
+ compiled; :attr:`co_firstlineno` is the first line number of the function;
+ :attr:`co_lnotab` is a string encoding the mapping from byte code offsets to
+ line numbers (for details see the source code of the interpreter);
+ :attr:`co_stacksize` is the required stack size (including local variables);
+ :attr:`co_flags` is an integer encoding a number of flags for the interpreter.
+
+ .. index::
+ single: co_argcount (code object attribute)
+ single: co_code (code object attribute)
+ single: co_consts (code object attribute)
+ single: co_filename (code object attribute)
+ single: co_firstlineno (code object attribute)
+ single: co_flags (code object attribute)
+ single: co_lnotab (code object attribute)
+ single: co_name (code object attribute)
+ single: co_names (code object attribute)
+ single: co_nlocals (code object attribute)
+ single: co_stacksize (code object attribute)
+ single: co_varnames (code object attribute)
+ single: co_cellvars (code object attribute)
+ single: co_freevars (code object attribute)
+
+ .. index:: object: generator
+
+ The following flag bits are defined for :attr:`co_flags`: bit ``0x04`` is set if
+ the function uses the ``*arguments`` syntax to accept an arbitrary number of
+ positional arguments; bit ``0x08`` is set if the function uses the
+ ``**keywords`` syntax to accept arbitrary keyword arguments; bit ``0x20`` is set
+ if the function is a generator.
+
+ Future feature declarations (``from __future__ import division``) also use bits
+ in :attr:`co_flags` to indicate whether a code object was compiled with a
+ particular feature enabled: bit ``0x2000`` is set if the function was compiled
+ with future division enabled; bits ``0x10`` and ``0x1000`` were used in earlier
+ versions of Python.
+
+ Other bits in :attr:`co_flags` are reserved for internal use.
+
+ .. index:: single: documentation string
+
+ If a code object represents a function, the first item in :attr:`co_consts` is
+ the documentation string of the function, or ``None`` if undefined.
+
+ Frame objects
+ .. index:: object: frame
+
+ Frame objects represent execution frames. They may occur in traceback objects
+ (see below).
+
+ .. index::
+ single: f_back (frame attribute)
+ single: f_code (frame attribute)
+ single: f_globals (frame attribute)
+ single: f_locals (frame attribute)
+ single: f_lasti (frame attribute)
+ single: f_builtins (frame attribute)
+
+ Special read-only attributes: :attr:`f_back` is to the previous stack frame
+ (towards the caller), or ``None`` if this is the bottom stack frame;
+ :attr:`f_code` is the code object being executed in this frame; :attr:`f_locals`
+ is the dictionary used to look up local variables; :attr:`f_globals` is used for
+ global variables; :attr:`f_builtins` is used for built-in (intrinsic) names;
+ :attr:`f_lasti` gives the precise instruction (this is an index into the
+ bytecode string of the code object).
+
+ .. index::
+ single: f_trace (frame attribute)
+ single: f_exc_type (frame attribute)
+ single: f_exc_value (frame attribute)
+ single: f_exc_traceback (frame attribute)
+ single: f_lineno (frame attribute)
+
+ Special writable attributes: :attr:`f_trace`, if not ``None``, is a function
+ called at the start of each source code line (this is used by the debugger);
+ :attr:`f_exc_type`, :attr:`f_exc_value`, :attr:`f_exc_traceback` represent the
+ last exception raised in the parent frame provided another exception was ever
+ raised in the current frame (in all other cases they are None); :attr:`f_lineno`
+ is the current line number of the frame --- writing to this from within a trace
+ function jumps to the given line (only for the bottom-most frame). A debugger
+ can implement a Jump command (aka Set Next Statement) by writing to f_lineno.
+
+ Traceback objects
+ .. index::
+ object: traceback
+ pair: stack; trace
+ pair: exception; handler
+ pair: execution; stack
+ single: exc_info (in module sys)
+ single: exc_traceback (in module sys)
+ single: last_traceback (in module sys)
+ single: sys.exc_info
+ single: sys.last_traceback
+
+ Traceback objects represent a stack trace of an exception. A traceback object
+ is created when an exception occurs. When the search for an exception handler
+ unwinds the execution stack, at each unwound level a traceback object is
+ inserted in front of the current traceback. When an exception handler is
+ entered, the stack trace is made available to the program. (See section
+ :ref:`try`.) It is accessible as the third item of the
+ tuple returned by ``sys.exc_info()``. When the program contains no suitable
+ handler, the stack trace is written (nicely formatted) to the standard error
+ stream; if the interpreter is interactive, it is also made available to the user
+ as ``sys.last_traceback``.
+
+ .. index::
+ single: tb_next (traceback attribute)
+ single: tb_frame (traceback attribute)
+ single: tb_lineno (traceback attribute)
+ single: tb_lasti (traceback attribute)
+ statement: try
+
+ Special read-only attributes: :attr:`tb_next` is the next level in the stack
+ trace (towards the frame where the exception occurred), or ``None`` if there is
+ no next level; :attr:`tb_frame` points to the execution frame of the current
+ level; :attr:`tb_lineno` gives the line number where the exception occurred;
+ :attr:`tb_lasti` indicates the precise instruction. The line number and last
+ instruction in the traceback may differ from the line number of its frame object
+ if the exception occurred in a :keyword:`try` statement with no matching except
+ clause or with a finally clause.
+
+ Slice objects
+ .. index:: builtin: slice
+
+ Slice objects are used to represent slices when *extended slice syntax* is used.
+ This is a slice using two colons, or multiple slices or ellipses separated by
+ commas, e.g., ``a[i:j:step]``, ``a[i:j, k:l]``, or ``a[..., i:j]``. They are
+ also created by the built-in :func:`slice` function.
+
+ .. index::
+ single: start (slice object attribute)
+ single: stop (slice object attribute)
+ single: step (slice object attribute)
+
+ Special read-only attributes: :attr:`start` is the lower bound; :attr:`stop` is
+ the upper bound; :attr:`step` is the step value; each is ``None`` if omitted.
+ These attributes can have any type.
+
+ Slice objects support one method:
+
+
+ .. method:: slice.indices(self, length)
+
+ This method takes a single integer argument *length* and computes information
+ about the extended slice that the slice object would describe if applied to a
+ sequence of *length* items. It returns a tuple of three integers; respectively
+ these are the *start* and *stop* indices and the *step* or stride length of the
+ slice. Missing or out-of-bounds indices are handled in a manner consistent with
+ regular slices.
+
+ .. versionadded:: 2.3
+
+ Static method objects
+ Static method objects provide a way of defeating the transformation of function
+ objects to method objects described above. A static method object is a wrapper
+ around any other object, usually a user-defined method object. When a static
+ method object is retrieved from a class or a class instance, the object actually
+ returned is the wrapped object, which is not subject to any further
+ transformation. Static method objects are not themselves callable, although the
+ objects they wrap usually are. Static method objects are created by the built-in
+ :func:`staticmethod` constructor.
+
+ Class method objects
+ A class method object, like a static method object, is a wrapper around another
+ object that alters the way in which that object is retrieved from classes and
+ class instances. The behaviour of class method objects upon such retrieval is
+ described above, under "User-defined methods". Class method objects are created
+ by the built-in :func:`classmethod` constructor.
+
+ .. % Internal types
+
+.. % Types
+.. % =========================================================================
+
+
+New-style and classic classes
+=============================
+
+Classes and instances come in two flavors: old-style or classic, and new-style.
+
+Up to Python 2.1, old-style classes were the only flavour available to the user.
+The concept of (old-style) class is unrelated to the concept of type: if *x* is
+an instance of an old-style class, then ``x.__class__`` designates the class of
+*x*, but ``type(x)`` is always ``<type 'instance'>``. This reflects the fact
+that all old-style instances, independently of their class, are implemented with
+a single built-in type, called ``instance``.
+
+New-style classes were introduced in Python 2.2 to unify classes and types. A
+new-style class neither more nor less than a user-defined type. If *x* is an
+instance of a new-style class, then ``type(x)`` is the same as ``x.__class__``.
+
+The major motivation for introducing new-style classes is to provide a unified
+object model with a full meta-model. It also has a number of immediate
+benefits, like the ability to subclass most built-in types, or the introduction
+of "descriptors", which enable computed properties.
+
+For compatibility reasons, classes are still old-style by default. New-style
+classes are created by specifying another new-style class (i.e. a type) as a
+parent class, or the "top-level type" :class:`object` if no other parent is
+needed. The behaviour of new-style classes differs from that of old-style
+classes in a number of important details in addition to what :func:`type`
+returns. Some of these changes are fundamental to the new object model, like
+the way special methods are invoked. Others are "fixes" that could not be
+implemented before for compatibility concerns, like the method resolution order
+in case of multiple inheritance.
+
+This manual is not up-to-date with respect to new-style classes. For now,
+please see http://www.python.org/doc/newstyle.html for more information.
+
+.. index::
+ single: class
+ single: class
+ single: class
+
+The plan is to eventually drop old-style classes, leaving only the semantics of
+new-style classes. This change will probably only be feasible in Python 3.0.
+new-style classic old-style
+
+.. % =========================================================================
+
+
+.. _specialnames:
+
+Special method names
+====================
+
+.. index::
+ pair: operator; overloading
+ single: __getitem__() (mapping object method)
+
+A class can implement certain operations that are invoked by special syntax
+(such as arithmetic operations or subscripting and slicing) by defining methods
+with special names. This is Python's approach to :dfn:`operator overloading`,
+allowing classes to define their own behavior with respect to language
+operators. For instance, if a class defines a method named :meth:`__getitem__`,
+and ``x`` is an instance of this class, then ``x[i]`` is equivalent [#]_ to
+``x.__getitem__(i)``. Except where mentioned, attempts to execute an operation
+raise an exception when no appropriate method is defined.
+
+When implementing a class that emulates any built-in type, it is important that
+the emulation only be implemented to the degree that it makes sense for the
+object being modelled. For example, some sequences may work well with retrieval
+of individual elements, but extracting a slice may not make sense. (One example
+of this is the :class:`NodeList` interface in the W3C's Document Object Model.)
+
+
+.. _customization:
+
+Basic customization
+-------------------
+
+
+.. method:: object.__new__(cls[, ...])
+
+ Called to create a new instance of class *cls*. :meth:`__new__` is a static
+ method (special-cased so you need not declare it as such) that takes the class
+ of which an instance was requested as its first argument. The remaining
+ arguments are those passed to the object constructor expression (the call to the
+ class). The return value of :meth:`__new__` should be the new object instance
+ (usually an instance of *cls*).
+
+ Typical implementations create a new instance of the class by invoking the
+ superclass's :meth:`__new__` method using ``super(currentclass,
+ cls).__new__(cls[, ...])`` with appropriate arguments and then modifying the
+ newly-created instance as necessary before returning it.
+
+ If :meth:`__new__` returns an instance of *cls*, then the new instance's
+ :meth:`__init__` method will be invoked like ``__init__(self[, ...])``, where
+ *self* is the new instance and the remaining arguments are the same as were
+ passed to :meth:`__new__`.
+
+ If :meth:`__new__` does not return an instance of *cls*, then the new instance's
+ :meth:`__init__` method will not be invoked.
+
+ :meth:`__new__` is intended mainly to allow subclasses of immutable types (like
+ int, str, or tuple) to customize instance creation.
+
+
+.. method:: object.__init__(self[, ...])
+
+ .. index:: pair: class; constructor
+
+ Called when the instance is created. The arguments are those passed to the
+ class constructor expression. If a base class has an :meth:`__init__` method,
+ the derived class's :meth:`__init__` method, if any, must explicitly call it to
+ ensure proper initialization of the base class part of the instance; for
+ example: ``BaseClass.__init__(self, [args...])``. As a special constraint on
+ constructors, no value may be returned; doing so will cause a :exc:`TypeError`
+ to be raised at runtime.
+
+
+.. method:: object.__del__(self)
+
+ .. index::
+ single: destructor
+ statement: del
+
+ Called when the instance is about to be destroyed. This is also called a
+ destructor. If a base class has a :meth:`__del__` method, the derived class's
+ :meth:`__del__` method, if any, must explicitly call it to ensure proper
+ deletion of the base class part of the instance. Note that it is possible
+ (though not recommended!) for the :meth:`__del__` method to postpone destruction
+ of the instance by creating a new reference to it. It may then be called at a
+ later time when this new reference is deleted. It is not guaranteed that
+ :meth:`__del__` methods are called for objects that still exist when the
+ interpreter exits.
+
+ .. note::
+
+ ``del x`` doesn't directly call ``x.__del__()`` --- the former decrements
+ the reference count for ``x`` by one, and the latter is only called when
+ ``x``'s reference count reaches zero. Some common situations that may
+ prevent the reference count of an object from going to zero include:
+ circular references between objects (e.g., a doubly-linked list or a tree
+ data structure with parent and child pointers); a reference to the object
+ on the stack frame of a function that caught an exception (the traceback
+ stored in ``sys.exc_info()[2]`` keeps the stack frame alive); or a
+ reference to the object on the stack frame that raised an unhandled
+ exception in interactive mode (the traceback stored in
+ ``sys.last_traceback`` keeps the stack frame alive). The first situation
+ can only be remedied by explicitly breaking the cycles; the latter two
+ situations can be resolved by storing ``None`` in ``sys.last_traceback``.
+ Circular references which are garbage are detected when the option cycle
+ detector is enabled (it's on by default), but can only be cleaned up if
+ there are no Python- level :meth:`__del__` methods involved. Refer to the
+ documentation for the :mod:`gc` module for more information about how
+ :meth:`__del__` methods are handled by the cycle detector, particularly
+ the description of the ``garbage`` value.
+
+ .. warning::
+
+ Due to the precarious circumstances under which :meth:`__del__` methods are
+ invoked, exceptions that occur during their execution are ignored, and a warning
+ is printed to ``sys.stderr`` instead. Also, when :meth:`__del__` is invoked in
+ response to a module being deleted (e.g., when execution of the program is
+ done), other globals referenced by the :meth:`__del__` method may already have
+ been deleted. For this reason, :meth:`__del__` methods should do the absolute
+ minimum needed to maintain external invariants. Starting with version 1.5,
+ Python guarantees that globals whose name begins with a single underscore are
+ deleted from their module before other globals are deleted; if no other
+ references to such globals exist, this may help in assuring that imported
+ modules are still available at the time when the :meth:`__del__` method is
+ called.
+
+
+.. method:: object.__repr__(self)
+
+ .. index:: builtin: repr
+
+ Called by the :func:`repr` built-in function and by string conversions (reverse
+ quotes) to compute the "official" string representation of an object. If at all
+ possible, this should look like a valid Python expression that could be used to
+ recreate an object with the same value (given an appropriate environment). If
+ this is not possible, a string of the form ``<...some useful description...>``
+ should be returned. The return value must be a string object. If a class
+ defines :meth:`__repr__` but not :meth:`__str__`, then :meth:`__repr__` is also
+ used when an "informal" string representation of instances of that class is
+ required.
+
+ .. index::
+ pair: string; conversion
+ pair: reverse; quotes
+ pair: backward; quotes
+ single: back-quotes
+
+ This is typically used for debugging, so it is important that the representation
+ is information-rich and unambiguous.
+
+
+.. method:: object.__str__(self)
+
+ .. index::
+ builtin: str
+ statement: print
+
+ Called by the :func:`str` built-in function and by the :keyword:`print`
+ statement to compute the "informal" string representation of an object. This
+ differs from :meth:`__repr__` in that it does not have to be a valid Python
+ expression: a more convenient or concise representation may be used instead.
+ The return value must be a string object.
+
+
+.. method:: object.__lt__(self, other)
+ object.__le__(self, other)
+ object.__eq__(self, other)
+ object.__ne__(self, other)
+ object.__gt__(self, other)
+ object.__ge__(self, other)
+
+ .. versionadded:: 2.1
+
+ These are the so-called "rich comparison" methods, and are called for comparison
+ operators in preference to :meth:`__cmp__` below. The correspondence between
+ operator symbols and method names is as follows: ``x<y`` calls ``x.__lt__(y)``,
+ ``x<=y`` calls ``x.__le__(y)``, ``x==y`` calls ``x.__eq__(y)``, ``x!=y`` calls
+ ``x.__ne__(y)``, ``x>y`` calls ``x.__gt__(y)``, and ``x>=y`` calls
+ ``x.__ge__(y)``.
+
+ A rich comparison method may return the singleton ``NotImplemented`` if it does
+ not implement the operation for a given pair of arguments. By convention,
+ ``False`` and ``True`` are returned for a successful comparison. However, these
+ methods can return any value, so if the comparison operator is used in a Boolean
+ context (e.g., in the condition of an ``if`` statement), Python will call
+ :func:`bool` on the value to determine if the result is true or false.
+
+ There are no implied relationships among the comparison operators. The truth of
+ ``x==y`` does not imply that ``x!=y`` is false. Accordingly, when defining
+ :meth:`__eq__`, one should also define :meth:`__ne__` so that the operators will
+ behave as expected.
+
+ There are no reflected (swapped-argument) versions of these methods (to be used
+ when the left argument does not support the operation but the right argument
+ does); rather, :meth:`__lt__` and :meth:`__gt__` are each other's reflection,
+ :meth:`__le__` and :meth:`__ge__` are each other's reflection, and
+ :meth:`__eq__` and :meth:`__ne__` are their own reflection.
+
+ Arguments to rich comparison methods are never coerced.
+
+
+.. method:: object.__cmp__(self, other)
+
+ .. index::
+ builtin: cmp
+ single: comparisons
+
+ Called by comparison operations if rich comparison (see above) is not defined.
+ Should return a negative integer if ``self < other``, zero if ``self == other``,
+ a positive integer if ``self > other``. If no :meth:`__cmp__`, :meth:`__eq__`
+ or :meth:`__ne__` operation is defined, class instances are compared by object
+ identity ("address"). See also the description of :meth:`__hash__` for some
+ important notes on creating objects which support custom comparison operations
+ and are usable as dictionary keys. (Note: the restriction that exceptions are
+ not propagated by :meth:`__cmp__` has been removed since Python 1.5.)
+
+
+.. method:: object.__rcmp__(self, other)
+
+ .. versionchanged:: 2.1
+ No longer supported.
+
+
+.. method:: object.__hash__(self)
+
+ .. index::
+ object: dictionary
+ builtin: hash
+
+ Called for the key object for dictionary operations, and by the built-in
+ function :func:`hash`. Should return a 32-bit integer usable as a hash value
+ for dictionary operations. The only required property is that objects which
+ compare equal have the same hash value; it is advised to somehow mix together
+ (e.g., using exclusive or) the hash values for the components of the object that
+ also play a part in comparison of objects. If a class does not define a
+ :meth:`__cmp__` method it should not define a :meth:`__hash__` operation either;
+ if it defines :meth:`__cmp__` or :meth:`__eq__` but not :meth:`__hash__`, its
+ instances will not be usable as dictionary keys. If a class defines mutable
+ objects and implements a :meth:`__cmp__` or :meth:`__eq__` method, it should not
+ implement :meth:`__hash__`, since the dictionary implementation requires that a
+ key's hash value is immutable (if the object's hash value changes, it will be in
+ the wrong hash bucket).
+
+ .. versionchanged:: 2.5
+ :meth:`__hash__` may now also return a long integer object; the 32-bit integer
+ is then derived from the hash of that object.
+
+ .. index:: single: __cmp__() (object method)
+
+
+.. method:: object.__bool__(self)
+
+ .. index:: single: __len__() (mapping object method)
+
+ Called to implement truth value testing, and the built-in operation ``bool()``;
+ should return ``False`` or ``True``. When this method is not defined,
+ :meth:`__len__` is called, if it is defined (see below) and ``True`` is returned
+ when the length is not zero. If a class defines neither :meth:`__len__` nor
+ :meth:`__bool__`, all its instances are considered true.
+
+
+.. method:: object.__unicode__(self)
+
+ .. index:: builtin: unicode
+
+ Called to implement :func:`unicode` builtin; should return a Unicode object.
+ When this method is not defined, string conversion is attempted, and the result
+ of string conversion is converted to Unicode using the system default encoding.
+
+
+.. _attribute-access:
+
+Customizing attribute access
+----------------------------
+
+The following methods can be defined to customize the meaning of attribute
+access (use of, assignment to, or deletion of ``x.name``) for class instances.
+
+
+.. method:: object.__getattr__(self, name)
+
+ Called when an attribute lookup has not found the attribute in the usual places
+ (i.e. it is not an instance attribute nor is it found in the class tree for
+ ``self``). ``name`` is the attribute name. This method should return the
+ (computed) attribute value or raise an :exc:`AttributeError` exception.
+
+ .. index:: single: __setattr__() (object method)
+
+ Note that if the attribute is found through the normal mechanism,
+ :meth:`__getattr__` is not called. (This is an intentional asymmetry between
+ :meth:`__getattr__` and :meth:`__setattr__`.) This is done both for efficiency
+ reasons and because otherwise :meth:`__setattr__` would have no way to access
+ other attributes of the instance. Note that at least for instance variables,
+ you can fake total control by not inserting any values in the instance attribute
+ dictionary (but instead inserting them in another object). See the
+ :meth:`__getattribute__` method below for a way to actually get total control in
+ new-style classes.
+
+
+.. method:: object.__setattr__(self, name, value)
+
+ Called when an attribute assignment is attempted. This is called instead of the
+ normal mechanism (i.e. store the value in the instance dictionary). *name* is
+ the attribute name, *value* is the value to be assigned to it.
+
+ .. index:: single: __dict__ (instance attribute)
+
+ If :meth:`__setattr__` wants to assign to an instance attribute, it should not
+ simply execute ``self.name = value`` --- this would cause a recursive call to
+ itself. Instead, it should insert the value in the dictionary of instance
+ attributes, e.g., ``self.__dict__[name] = value``. For new-style classes,
+ rather than accessing the instance dictionary, it should call the base class
+ method with the same name, for example, ``object.__setattr__(self, name,
+ value)``.
+
+
+.. method:: object.__delattr__(self, name)
+
+ Like :meth:`__setattr__` but for attribute deletion instead of assignment. This
+ should only be implemented if ``del obj.name`` is meaningful for the object.
+
+
+.. _new-style-attribute-access:
+
+More attribute access for new-style classes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following methods only apply to new-style classes.
+
+
+.. method:: object.__getattribute__(self, name)
+
+ Called unconditionally to implement attribute accesses for instances of the
+ class. If the class also defines :meth:`__getattr__`, the latter will not be
+ called unless :meth:`__getattribute__` either calls it explicitly or raises an
+ :exc:`AttributeError`. This method should return the (computed) attribute value
+ or raise an :exc:`AttributeError` exception. In order to avoid infinite
+ recursion in this method, its implementation should always call the base class
+ method with the same name to access any attributes it needs, for example,
+ ``object.__getattribute__(self, name)``.
+
+
+.. _descriptors:
+
+Implementing Descriptors
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following methods only apply when an instance of the class containing the
+method (a so-called *descriptor* class) appears in the class dictionary of
+another new-style class, known as the *owner* class. In the examples below, "the
+attribute" refers to the attribute whose name is the key of the property in the
+owner class' ``__dict__``. Descriptors can only be implemented as new-style
+classes themselves.
+
+
+.. method:: object.__get__(self, instance, owner)
+
+ Called to get the attribute of the owner class (class attribute access) or of an
+ instance of that class (instance attribute access). *owner* is always the owner
+ class, while *instance* is the instance that the attribute was accessed through,
+ or ``None`` when the attribute is accessed through the *owner*. This method
+ should return the (computed) attribute value or raise an :exc:`AttributeError`
+ exception.
+
+
+.. method:: object.__set__(self, instance, value)
+
+ Called to set the attribute on an instance *instance* of the owner class to a
+ new value, *value*.
+
+
+.. method:: object.__delete__(self, instance)
+
+ Called to delete the attribute on an instance *instance* of the owner class.
+
+
+.. _descriptor-invocation:
+
+Invoking Descriptors
+^^^^^^^^^^^^^^^^^^^^
+
+In general, a descriptor is an object attribute with "binding behavior", one
+whose attribute access has been overridden by methods in the descriptor
+protocol: :meth:`__get__`, :meth:`__set__`, and :meth:`__delete__`. If any of
+those methods are defined for an object, it is said to be a descriptor.
+
+The default behavior for attribute access is to get, set, or delete the
+attribute from an object's dictionary. For instance, ``a.x`` has a lookup chain
+starting with ``a.__dict__['x']``, then ``type(a).__dict__['x']``, and
+continuing through the base classes of ``type(a)`` excluding metaclasses.
+
+However, if the looked-up value is an object defining one of the descriptor
+methods, then Python may override the default behavior and invoke the descriptor
+method instead. Where this occurs in the precedence chain depends on which
+descriptor methods were defined and how they were called. Note that descriptors
+are only invoked for new style objects or classes (ones that subclass
+:class:`object()` or :class:`type()`).
+
+The starting point for descriptor invocation is a binding, ``a.x``. How the
+arguments are assembled depends on ``a``:
+
+Direct Call
+ The simplest and least common call is when user code directly invokes a
+ descriptor method: ``x.__get__(a)``.
+
+Instance Binding
+ If binding to a new-style object instance, ``a.x`` is transformed into the call:
+ ``type(a).__dict__['x'].__get__(a, type(a))``.
+
+Class Binding
+ If binding to a new-style class, ``A.x`` is transformed into the call:
+ ``A.__dict__['x'].__get__(None, A)``.
+
+Super Binding
+ If ``a`` is an instance of :class:`super`, then the binding ``super(B,
+ obj).m()`` searches ``obj.__class__.__mro__`` for the base class ``A``
+ immediately preceding ``B`` and then invokes the descriptor with the call:
+ ``A.__dict__['m'].__get__(obj, A)``.
+
+For instance bindings, the precedence of descriptor invocation depends on the
+which descriptor methods are defined. Data descriptors define both
+:meth:`__get__` and :meth:`__set__`. Non-data descriptors have just the
+:meth:`__get__` method. Data descriptors always override a redefinition in an
+instance dictionary. In contrast, non-data descriptors can be overridden by
+instances.
+
+Python methods (including :func:`staticmethod` and :func:`classmethod`) are
+implemented as non-data descriptors. Accordingly, instances can redefine and
+override methods. This allows individual instances to acquire behaviors that
+differ from other instances of the same class.
+
+The :func:`property` function is implemented as a data descriptor. Accordingly,
+instances cannot override the behavior of a property.
+
+
+.. _slots:
+
+__slots__
+^^^^^^^^^
+
+By default, instances of both old and new-style classes have a dictionary for
+attribute storage. This wastes space for objects having very few instance
+variables. The space consumption can become acute when creating large numbers
+of instances.
+
+The default can be overridden by defining *__slots__* in a new-style class
+definition. The *__slots__* declaration takes a sequence of instance variables
+and reserves just enough space in each instance to hold a value for each
+variable. Space is saved because *__dict__* is not created for each instance.
+
+
+.. data:: __slots__
+
+ This class variable can be assigned a string, iterable, or sequence of strings
+ with variable names used by instances. If defined in a new-style class,
+ *__slots__* reserves space for the declared variables and prevents the automatic
+ creation of *__dict__* and *__weakref__* for each instance.
+
+ .. versionadded:: 2.2
+
+Notes on using *__slots__*
+
+* Without a *__dict__* variable, instances cannot be assigned new variables not
+ listed in the *__slots__* definition. Attempts to assign to an unlisted
+ variable name raises :exc:`AttributeError`. If dynamic assignment of new
+ variables is desired, then add ``'__dict__'`` to the sequence of strings in the
+ *__slots__* declaration.
+
+ .. versionchanged:: 2.3
+ Previously, adding ``'__dict__'`` to the *__slots__* declaration would not
+ enable the assignment of new attributes not specifically listed in the sequence
+ of instance variable names.
+
+* Without a *__weakref__* variable for each instance, classes defining
+ *__slots__* do not support weak references to its instances. If weak reference
+ support is needed, then add ``'__weakref__'`` to the sequence of strings in the
+ *__slots__* declaration.
+
+ .. versionchanged:: 2.3
+ Previously, adding ``'__weakref__'`` to the *__slots__* declaration would not
+ enable support for weak references.
+
+* *__slots__* are implemented at the class level by creating descriptors
+ (:ref:`descriptors`) for each variable name. As a result, class attributes
+ cannot be used to set default values for instance variables defined by
+ *__slots__*; otherwise, the class attribute would overwrite the descriptor
+ assignment.
+
+* If a class defines a slot also defined in a base class, the instance variable
+ defined by the base class slot is inaccessible (except by retrieving its
+ descriptor directly from the base class). This renders the meaning of the
+ program undefined. In the future, a check may be added to prevent this.
+
+* The action of a *__slots__* declaration is limited to the class where it is
+ defined. As a result, subclasses will have a *__dict__* unless they also define
+ *__slots__*.
+
+* *__slots__* do not work for classes derived from "variable-length" built-in
+ types such as :class:`long`, :class:`str` and :class:`tuple`.
+
+* Any non-string iterable may be assigned to *__slots__*. Mappings may also be
+ used; however, in the future, special meaning may be assigned to the values
+ corresponding to each key.
+
+* *__class__* assignment works only if both classes have the same *__slots__*.
+
+ .. versionchanged:: 2.6
+ Previously, *__class__* assignment raised an error if either new or old class
+ had *__slots__*.
+
+
+.. _metaclasses:
+
+Customizing class creation
+--------------------------
+
+By default, new-style classes are constructed using :func:`type`. A class
+definition is read into a separate namespace and the value of class name is
+bound to the result of ``type(name, bases, dict)``.
+
+When the class definition is read, if *__metaclass__* is defined then the
+callable assigned to it will be called instead of :func:`type`. The allows
+classes or functions to be written which monitor or alter the class creation
+process:
+
+* Modifying the class dictionary prior to the class being created.
+
+* Returning an instance of another class -- essentially performing the role of a
+ factory function.
+
+
+.. data:: __metaclass__
+
+ This variable can be any callable accepting arguments for ``name``, ``bases``,
+ and ``dict``. Upon class creation, the callable is used instead of the built-in
+ :func:`type`.
+
+ .. versionadded:: 2.2
+
+The appropriate metaclass is determined by the following precedence rules:
+
+* If ``dict['__metaclass__']`` exists, it is used.
+
+* Otherwise, if there is at least one base class, its metaclass is used (this
+ looks for a *__class__* attribute first and if not found, uses its type).
+
+* Otherwise, if a global variable named __metaclass__ exists, it is used.
+
+* Otherwise, the old-style, classic metaclass (types.ClassType) is used.
+
+The potential uses for metaclasses are boundless. Some ideas that have been
+explored including logging, interface checking, automatic delegation, automatic
+property creation, proxies, frameworks, and automatic resource
+locking/synchronization.
+
+
+.. _callable-types:
+
+Emulating callable objects
+--------------------------
+
+
+.. method:: object.__call__(self[, args...])
+
+ .. index:: pair: call; instance
+
+ Called when the instance is "called" as a function; if this method is defined,
+ ``x(arg1, arg2, ...)`` is a shorthand for ``x.__call__(arg1, arg2, ...)``.
+
+
+.. _sequence-types:
+
+Emulating container types
+-------------------------
+
+The following methods can be defined to implement container objects. Containers
+usually are sequences (such as lists or tuples) or mappings (like dictionaries),
+but can represent other containers as well. The first set of methods is used
+either to emulate a sequence or to emulate a mapping; the difference is that for
+a sequence, the allowable keys should be the integers *k* for which ``0 <= k <
+N`` where *N* is the length of the sequence, or slice objects, which define a
+range of items. (For backwards compatibility, the method :meth:`__getslice__`
+(see below) can also be defined to handle simple, but not extended slices.) It
+is also recommended that mappings provide the methods :meth:`keys`,
+:meth:`values`, :meth:`items`, :meth:`has_key`, :meth:`get`, :meth:`clear`,
+:meth:`setdefault`, :meth:`iterkeys`, :meth:`itervalues`, :meth:`iteritems`,
+:meth:`pop`, :meth:`popitem`, :meth:`copy`, and :meth:`update` behaving similar
+to those for Python's standard dictionary objects. The :mod:`UserDict` module
+provides a :class:`DictMixin` class to help create those methods from a base set
+of :meth:`__getitem__`, :meth:`__setitem__`, :meth:`__delitem__`, and
+:meth:`keys`. Mutable sequences should provide methods :meth:`append`,
+:meth:`count`, :meth:`index`, :meth:`extend`, :meth:`insert`, :meth:`pop`,
+:meth:`remove`, :meth:`reverse` and :meth:`sort`, like Python standard list
+objects. Finally, sequence types should implement addition (meaning
+concatenation) and multiplication (meaning repetition) by defining the methods
+:meth:`__add__`, :meth:`__radd__`, :meth:`__iadd__`, :meth:`__mul__`,
+:meth:`__rmul__` and :meth:`__imul__` described below; they should not define
+other numerical operators. It is recommended that both mappings and sequences
+implement the :meth:`__contains__` method to allow efficient use of the ``in``
+operator; for mappings, ``in`` should be equivalent of :meth:`has_key`; for
+sequences, it should search through the values. It is further recommended that
+both mappings and sequences implement the :meth:`__iter__` method to allow
+efficient iteration through the container; for mappings, :meth:`__iter__` should
+be the same as :meth:`iterkeys`; for sequences, it should iterate through the
+values.
+
+
+.. method:: object.__len__(self)
+
+ .. index::
+ builtin: len
+ single: __bool__() (object method)
+
+ Called to implement the built-in function :func:`len`. Should return the length
+ of the object, an integer ``>=`` 0. Also, an object that doesn't define a
+ :meth:`__bool__` method and whose :meth:`__len__` method returns zero is
+ considered to be false in a Boolean context.
+
+
+.. method:: object.__getitem__(self, key)
+
+ .. index:: object: slice
+
+ Called to implement evaluation of ``self[key]``. For sequence types, the
+ accepted keys should be integers and slice objects. Note that the special
+ interpretation of negative indexes (if the class wishes to emulate a sequence
+ type) is up to the :meth:`__getitem__` method. If *key* is of an inappropriate
+ type, :exc:`TypeError` may be raised; if of a value outside the set of indexes
+ for the sequence (after any special interpretation of negative values),
+ :exc:`IndexError` should be raised. For mapping types, if *key* is missing (not
+ in the container), :exc:`KeyError` should be raised.
+
+ .. note::
+
+ :keyword:`for` loops expect that an :exc:`IndexError` will be raised for illegal
+ indexes to allow proper detection of the end of the sequence.
+
+
+.. method:: object.__setitem__(self, key, value)
+
+ Called to implement assignment to ``self[key]``. Same note as for
+ :meth:`__getitem__`. This should only be implemented for mappings if the
+ objects support changes to the values for keys, or if new keys can be added, or
+ for sequences if elements can be replaced. The same exceptions should be raised
+ for improper *key* values as for the :meth:`__getitem__` method.
+
+
+.. method:: object.__delitem__(self, key)
+
+ Called to implement deletion of ``self[key]``. Same note as for
+ :meth:`__getitem__`. This should only be implemented for mappings if the
+ objects support removal of keys, or for sequences if elements can be removed
+ from the sequence. The same exceptions should be raised for improper *key*
+ values as for the :meth:`__getitem__` method.
+
+
+.. method:: object.__iter__(self)
+
+ This method is called when an iterator is required for a container. This method
+ should return a new iterator object that can iterate over all the objects in the
+ container. For mappings, it should iterate over the keys of the container, and
+ should also be made available as the method :meth:`iterkeys`.
+
+ Iterator objects also need to implement this method; they are required to return
+ themselves. For more information on iterator objects, see :ref:`typeiter`.
+
+The membership test operators (:keyword:`in` and :keyword:`not in`) are normally
+implemented as an iteration through a sequence. However, container objects can
+supply the following special method with a more efficient implementation, which
+also does not require the object be a sequence.
+
+
+.. method:: object.__contains__(self, item)
+
+ Called to implement membership test operators. Should return true if *item* is
+ in *self*, false otherwise. For mapping objects, this should consider the keys
+ of the mapping rather than the values or the key-item pairs.
+
+
+.. _sequence-methods:
+
+Additional methods for emulation of sequence types
+--------------------------------------------------
+
+The following optional methods can be defined to further emulate sequence
+objects. Immutable sequences methods should at most only define
+:meth:`__getslice__`; mutable sequences might define all three methods.
+
+
+.. method:: object.__getslice__(self, i, j)
+
+ .. deprecated:: 2.0
+ Support slice objects as parameters to the :meth:`__getitem__` method.
+
+ Called to implement evaluation of ``self[i:j]``. The returned object should be
+ of the same type as *self*. Note that missing *i* or *j* in the slice
+ expression are replaced by zero or ``sys.maxint``, respectively. If negative
+ indexes are used in the slice, the length of the sequence is added to that
+ index. If the instance does not implement the :meth:`__len__` method, an
+ :exc:`AttributeError` is raised. No guarantee is made that indexes adjusted this
+ way are not still negative. Indexes which are greater than the length of the
+ sequence are not modified. If no :meth:`__getslice__` is found, a slice object
+ is created instead, and passed to :meth:`__getitem__` instead.
+
+
+.. method:: object.__setslice__(self, i, j, sequence)
+
+ Called to implement assignment to ``self[i:j]``. Same notes for *i* and *j* as
+ for :meth:`__getslice__`.
+
+ This method is deprecated. If no :meth:`__setslice__` is found, or for extended
+ slicing of the form ``self[i:j:k]``, a slice object is created, and passed to
+ :meth:`__setitem__`, instead of :meth:`__setslice__` being called.
+
+
+.. method:: object.__delslice__(self, i, j)
+
+ Called to implement deletion of ``self[i:j]``. Same notes for *i* and *j* as for
+ :meth:`__getslice__`. This method is deprecated. If no :meth:`__delslice__` is
+ found, or for extended slicing of the form ``self[i:j:k]``, a slice object is
+ created, and passed to :meth:`__delitem__`, instead of :meth:`__delslice__`
+ being called.
+
+Notice that these methods are only invoked when a single slice with a single
+colon is used, and the slice method is available. For slice operations
+involving extended slice notation, or in absence of the slice methods,
+:meth:`__getitem__`, :meth:`__setitem__` or :meth:`__delitem__` is called with a
+slice object as argument.
+
+The following example demonstrate how to make your program or module compatible
+with earlier versions of Python (assuming that methods :meth:`__getitem__`,
+:meth:`__setitem__` and :meth:`__delitem__` support slice objects as
+arguments)::
+
+ class MyClass:
+ ...
+ def __getitem__(self, index):
+ ...
+ def __setitem__(self, index, value):
+ ...
+ def __delitem__(self, index):
+ ...
+
+ if sys.version_info < (2, 0):
+ # They won't be defined if version is at least 2.0 final
+
+ def __getslice__(self, i, j):
+ return self[max(0, i):max(0, j):]
+ def __setslice__(self, i, j, seq):
+ self[max(0, i):max(0, j):] = seq
+ def __delslice__(self, i, j):
+ del self[max(0, i):max(0, j):]
+ ...
+
+Note the calls to :func:`max`; these are necessary because of the handling of
+negative indices before the :meth:`__\*slice__` methods are called. When
+negative indexes are used, the :meth:`__\*item__` methods receive them as
+provided, but the :meth:`__\*slice__` methods get a "cooked" form of the index
+values. For each negative index value, the length of the sequence is added to
+the index before calling the method (which may still result in a negative
+index); this is the customary handling of negative indexes by the built-in
+sequence types, and the :meth:`__\*item__` methods are expected to do this as
+well. However, since they should already be doing that, negative indexes cannot
+be passed in; they must be constrained to the bounds of the sequence before
+being passed to the :meth:`__\*item__` methods. Calling ``max(0, i)``
+conveniently returns the proper value.
+
+
+.. _numeric-types:
+
+Emulating numeric types
+-----------------------
+
+The following methods can be defined to emulate numeric objects. Methods
+corresponding to operations that are not supported by the particular kind of
+number implemented (e.g., bitwise operations for non-integral numbers) should be
+left undefined.
+
+
+.. method:: object.__add__(self, other)
+ object.__sub__(self, other)
+ object.__mul__(self, other)
+ object.__floordiv__(self, other)
+ object.__mod__(self, other)
+ object.__divmod__(self, other)
+ object.__pow__(self, other[, modulo])
+ object.__lshift__(self, other)
+ object.__rshift__(self, other)
+ object.__and__(self, other)
+ object.__xor__(self, other)
+ object.__or__(self, other)
+
+ .. index::
+ builtin: divmod
+ builtin: pow
+ builtin: pow
+
+ These methods are called to implement the binary arithmetic operations (``+``,
+ ``-``, ``*``, ``//``, ``%``, :func:`divmod`, :func:`pow`, ``**``, ``<<``,
+ ``>>``, ``&``, ``^``, ``|``). For instance, to evaluate the expression
+ *x*``+``*y*, where *x* is an instance of a class that has an :meth:`__add__`
+ method, ``x.__add__(y)`` is called. The :meth:`__divmod__` method should be the
+ equivalent to using :meth:`__floordiv__` and :meth:`__mod__`; it should not be
+ related to :meth:`__truediv__` (described below). Note that :meth:`__pow__`
+ should be defined to accept an optional third argument if the ternary version of
+ the built-in :func:`pow` function is to be supported.
+
+ If one of those methods does not support the operation with the supplied
+ arguments, it should return ``NotImplemented``.
+
+
+.. method:: object.__div__(self, other)
+ object.__truediv__(self, other)
+
+ The division operator (``/``) is implemented by these methods. The
+ :meth:`__truediv__` method is used when ``__future__.division`` is in effect,
+ otherwise :meth:`__div__` is used. If only one of these two methods is defined,
+ the object will not support division in the alternate context; :exc:`TypeError`
+ will be raised instead.
+
+
+.. method:: object.__radd__(self, other)
+ object.__rsub__(self, other)
+ object.__rmul__(self, other)
+ object.__rdiv__(self, other)
+ object.__rtruediv__(self, other)
+ object.__rfloordiv__(self, other)
+ object.__rmod__(self, other)
+ object.__rdivmod__(self, other)
+ object.__rpow__(self, other)
+ object.__rlshift__(self, other)
+ object.__rrshift__(self, other)
+ object.__rand__(self, other)
+ object.__rxor__(self, other)
+ object.__ror__(self, other)
+
+ .. index::
+ builtin: divmod
+ builtin: pow
+
+ These methods are called to implement the binary arithmetic operations (``+``,
+ ``-``, ``*``, ``/``, ``%``, :func:`divmod`, :func:`pow`, ``**``, ``<<``, ``>>``,
+ ``&``, ``^``, ``|``) with reflected (swapped) operands. These functions are
+ only called if the left operand does not support the corresponding operation and
+ the operands are of different types. [#]_ For instance, to evaluate the
+ expression *x*``-``*y*, where *y* is an instance of a class that has an
+ :meth:`__rsub__` method, ``y.__rsub__(x)`` is called if ``x.__sub__(y)`` returns
+ *NotImplemented*.
+
+ .. index:: builtin: pow
+
+ Note that ternary :func:`pow` will not try calling :meth:`__rpow__` (the
+ coercion rules would become too complicated).
+
+ .. note::
+
+ If the right operand's type is a subclass of the left operand's type and that
+ subclass provides the reflected method for the operation, this method will be
+ called before the left operand's non-reflected method. This behavior allows
+ subclasses to override their ancestors' operations.
+
+
+.. method:: object.__iadd__(self, other)
+ object.__isub__(self, other)
+ object.__imul__(self, other)
+ object.__idiv__(self, other)
+ object.__itruediv__(self, other)
+ object.__ifloordiv__(self, other)
+ object.__imod__(self, other)
+ object.__ipow__(self, other[, modulo])
+ object.__ilshift__(self, other)
+ object.__irshift__(self, other)
+ object.__iand__(self, other)
+ object.__ixor__(self, other)
+ object.__ior__(self, other)
+
+ These methods are called to implement the augmented arithmetic operations
+ (``+=``, ``-=``, ``*=``, ``/=``, ``//=``, ``%=``, ``**=``, ``<<=``, ``>>=``,
+ ``&=``, ``^=``, ``|=``). These methods should attempt to do the operation
+ in-place (modifying *self*) and return the result (which could be, but does
+ not have to be, *self*). If a specific method is not defined, the augmented
+ operation falls back to the normal methods. For instance, to evaluate the
+ expression *x*``+=``*y*, where *x* is an instance of a class that has an
+ :meth:`__iadd__` method, ``x.__iadd__(y)`` is called. If *x* is an instance
+ of a class that does not define a :meth:`__iadd__` method, ``x.__add__(y)``
+ and ``y.__radd__(x)`` are considered, as with the evaluation of *x*``+``*y*.
+
+
+.. method:: object.__neg__(self)
+ object.__pos__(self)
+ object.__abs__(self)
+ object.__invert__(self)
+
+ .. index:: builtin: abs
+
+ Called to implement the unary arithmetic operations (``-``, ``+``, :func:`abs`
+ and ``~``).
+
+
+.. method:: object.__complex__(self)
+ object.__int__(self)
+ object.__long__(self)
+ object.__float__(self)
+
+ .. index::
+ builtin: complex
+ builtin: int
+ builtin: long
+ builtin: float
+
+ Called to implement the built-in functions :func:`complex`, :func:`int`,
+ :func:`long`, and :func:`float`. Should return a value of the appropriate type.
+
+
+.. method:: object.__index__(self)
+
+ Called to implement :func:`operator.index`. Also called whenever Python needs
+ an integer object (such as in slicing, or in the built-in :func:`bin`,
+ :func:`hex` and :func:`oct` functions). Must return an integer (int or long).
+
+ .. versionadded:: 2.5
+
+
+.. _context-managers:
+
+With Statement Context Managers
+-------------------------------
+
+.. versionadded:: 2.5
+
+A :dfn:`context manager` is an object that defines the runtime context to be
+established when executing a :keyword:`with` statement. The context manager
+handles the entry into, and the exit from, the desired runtime context for the
+execution of the block of code. Context managers are normally invoked using the
+:keyword:`with` statement (described in section :ref:`with`), but can also be
+used by directly invoking their methods.
+
+.. index::
+ statement: with
+ single: context manager
+
+Typical uses of context managers include saving and restoring various kinds of
+global state, locking and unlocking resources, closing opened files, etc.
+
+For more information on context managers, see :ref:`typecontextmanager`.
+
+
+.. method:: object.__enter__(self)
+
+ Enter the runtime context related to this object. The :keyword:`with` statement
+ will bind this method's return value to the target(s) specified in the
+ :keyword:`as` clause of the statement, if any.
+
+
+.. method:: object.__exit__(self, exc_type, exc_value, traceback)
+
+ Exit the runtime context related to this object. The parameters describe the
+ exception that caused the context to be exited. If the context was exited
+ without an exception, all three arguments will be :const:`None`.
+
+ If an exception is supplied, and the method wishes to suppress the exception
+ (i.e., prevent it from being propagated), it should return a true value.
+ Otherwise, the exception will be processed normally upon exit from this method.
+
+ Note that :meth:`__exit__` methods should not reraise the passed-in exception;
+ this is the caller's responsibility.
+
+
+.. seealso::
+
+ :pep:`0343` - The "with" statement
+ The specification, background, and examples for the Python :keyword:`with`
+ statement.
+
+.. rubric:: Footnotes
+
+.. [#] Since Python 2.2, a gradual merging of types and classes has been started that
+ makes this and a few other assertions made in this manual not 100% accurate and
+ complete: for example, it *is* now possible in some cases to change an object's
+ type, under certain controlled conditions. Until this manual undergoes
+ extensive revision, it must now be taken as authoritative only regarding
+ "classic classes", that are still the default, for compatibility purposes, in
+ Python 2.2 and 2.3. For more information, see
+ http://www.python.org/doc/newstyle.html.
+
+.. [#] This, and other statements, are only roughly true for instances of new-style
+ classes.
+
+.. [#] For operands of the same type, it is assumed that if the non-reflected method
+ (such as :meth:`__add__`) fails the operation is not supported, which is why the
+ reflected method is not called.
+
diff --git a/Doc/reference/executionmodel.rst b/Doc/reference/executionmodel.rst
new file mode 100644
index 0000000000..27802c8b85
--- /dev/null
+++ b/Doc/reference/executionmodel.rst
@@ -0,0 +1,232 @@
+
+.. _execmodel:
+
+***************
+Execution model
+***************
+
+.. index:: single: execution model
+
+
+.. _naming:
+
+Naming and binding
+==================
+
+.. index::
+ pair: code; block
+ single: namespace
+ single: scope
+
+.. index::
+ single: name
+ pair: binding; name
+
+:dfn:`Names` refer to objects. Names are introduced by name binding operations.
+Each occurrence of a name in the program text refers to the :dfn:`binding` of
+that name established in the innermost function block containing the use.
+
+.. index:: single: block
+
+A :dfn:`block` is a piece of Python program text that is executed as a unit.
+The following are blocks: a module, a function body, and a class definition.
+Each command typed interactively is a block. A script file (a file given as
+standard input to the interpreter or specified on the interpreter command line
+the first argument) is a code block. A script command (a command specified on
+the interpreter command line with the '**-c**' option) is a code block. The string
+argument passed to the built-in functions :func:`eval` and :func:`exec` is a
+code block. The expression read and evaluated by the built-in function
+:func:`input` is a code block.
+
+.. index:: pair: execution; frame
+
+A code block is executed in an :dfn:`execution frame`. A frame contains some
+administrative information (used for debugging) and determines where and how
+execution continues after the code block's execution has completed.
+
+.. index:: single: scope
+
+A :dfn:`scope` defines the visibility of a name within a block. If a local
+variable is defined in a block, its scope includes that block. If the
+definition occurs in a function block, the scope extends to any blocks contained
+within the defining one, unless a contained block introduces a different binding
+for the name. The scope of names defined in a class block is limited to the
+class block; it does not extend to the code blocks of methods.
+
+.. index:: single: environment
+
+When a name is used in a code block, it is resolved using the nearest enclosing
+scope. The set of all such scopes visible to a code block is called the block's
+:dfn:`environment`.
+
+.. index:: pair: free; variable
+
+If a name is bound in a block, it is a local variable of that block. If a name
+is bound at the module level, it is a global variable. (The variables of the
+module code block are local and global.) If a variable is used in a code block
+but not defined there, it is a :dfn:`free variable`.
+
+.. index::
+ single: NameError (built-in exception)
+ single: UnboundLocalError
+
+When a name is not found at all, a :exc:`NameError` exception is raised. If the
+name refers to a local variable that has not been bound, a
+:exc:`UnboundLocalError` exception is raised. :exc:`UnboundLocalError` is a
+subclass of :exc:`NameError`.
+
+.. index:: statement: from
+
+The following constructs bind names: formal parameters to functions,
+:keyword:`import` statements, class and function definitions (these bind the
+class or function name in the defining block), and targets that are identifiers
+if occurring in an assignment, :keyword:`for` loop header, or in the second
+position of an :keyword:`except` clause header. The :keyword:`import` statement
+of the form "``from ...import *``" binds all names defined in the imported
+module, except those beginning with an underscore. This form may only be used
+at the module level.
+
+A target occurring in a :keyword:`del` statement is also considered bound for
+this purpose (though the actual semantics are to unbind the name). It is
+illegal to unbind a name that is referenced by an enclosing scope; the compiler
+will report a :exc:`SyntaxError`.
+
+Each assignment or import statement occurs within a block defined by a class or
+function definition or at the module level (the top-level code block).
+
+If a name binding operation occurs anywhere within a code block, all uses of the
+name within the block are treated as references to the current block. This can
+lead to errors when a name is used within a block before it is bound. This rule
+is subtle. Python lacks declarations and allows name binding operations to
+occur anywhere within a code block. The local variables of a code block can be
+determined by scanning the entire text of the block for name binding operations.
+
+If the global statement occurs within a block, all uses of the name specified in
+the statement refer to the binding of that name in the top-level namespace.
+Names are resolved in the top-level namespace by searching the global namespace,
+i.e. the namespace of the module containing the code block, and the builtin
+namespace, the namespace of the module :mod:`__builtin__`. The global namespace
+is searched first. If the name is not found there, the builtin namespace is
+searched. The global statement must precede all uses of the name.
+
+.. index:: pair: restricted; execution
+
+The built-in namespace associated with the execution of a code block is actually
+found by looking up the name ``__builtins__`` in its global namespace; this
+should be a dictionary or a module (in the latter case the module's dictionary
+is used). By default, when in the :mod:`__main__` module, ``__builtins__`` is
+the built-in module :mod:`__builtin__` (note: no 's'); when in any other module,
+``__builtins__`` is an alias for the dictionary of the :mod:`__builtin__` module
+itself. ``__builtins__`` can be set to a user-created dictionary to create a
+weak form of restricted execution.
+
+.. note::
+
+ Users should not touch ``__builtins__``; it is strictly an implementation
+ detail. Users wanting to override values in the built-in namespace should
+ :keyword:`import` the :mod:`__builtin__` (no 's') module and modify its
+ attributes appropriately.
+
+.. index:: module: __main__
+
+The namespace for a module is automatically created the first time a module is
+imported. The main module for a script is always called :mod:`__main__`.
+
+The global statement has the same scope as a name binding operation in the same
+block. If the nearest enclosing scope for a free variable contains a global
+statement, the free variable is treated as a global.
+
+A class definition is an executable statement that may use and define names.
+These references follow the normal rules for name resolution. The namespace of
+the class definition becomes the attribute dictionary of the class. Names
+defined at the class scope are not visible in methods.
+
+
+.. _dynamic-features:
+
+Interaction with dynamic features
+---------------------------------
+
+There are several cases where Python statements are illegal when used in
+conjunction with nested scopes that contain free variables.
+
+If a variable is referenced in an enclosing scope, it is illegal to delete the
+name. An error will be reported at compile time.
+
+If the wild card form of import --- ``import *`` --- is used in a function and
+the function contains or is a nested block with free variables, the compiler
+will raise a :exc:`SyntaxError`.
+
+The :func:`eval` and :func:`exec` functions do
+not have access to the full environment for resolving names. Names may be
+resolved in the local and global namespaces of the caller. Free variables are
+not resolved in the nearest enclosing namespace, but in the global namespace.
+[#]_ The :func:`exec` and :func:`eval` functions have optional
+arguments to override the global and local namespace. If only one namespace is
+specified, it is used for both.
+
+
+.. _exceptions:
+
+Exceptions
+==========
+
+.. index:: single: exception
+
+.. index::
+ single: raise an exception
+ single: handle an exception
+ single: exception handler
+ single: errors
+ single: error handling
+
+Exceptions are a means of breaking out of the normal flow of control of a code
+block in order to handle errors or other exceptional conditions. An exception
+is *raised* at the point where the error is detected; it may be *handled* by the
+surrounding code block or by any code block that directly or indirectly invoked
+the code block where the error occurred.
+
+The Python interpreter raises an exception when it detects a run-time error
+(such as division by zero). A Python program can also explicitly raise an
+exception with the :keyword:`raise` statement. Exception handlers are specified
+with the :keyword:`try` ... :keyword:`except` statement. The :keyword:`try` ...
+:keyword:`finally` statement specifies cleanup code which does not handle the
+exception, but is executed whether an exception occurred or not in the preceding
+code.
+
+.. index:: single: termination model
+
+Python uses the "termination" model of error handling: an exception handler can
+find out what happened and continue execution at an outer level, but it cannot
+repair the cause of the error and retry the failing operation (except by
+re-entering the offending piece of code from the top).
+
+.. index:: single: SystemExit (built-in exception)
+
+When an exception is not handled at all, the interpreter terminates execution of
+the program, or returns to its interactive main loop. In either case, it prints
+a stack backtrace, except when the exception is :exc:`SystemExit`.
+
+Exceptions are identified by class instances. The :keyword:`except` clause is
+selected depending on the class of the instance: it must reference the class of
+the instance or a base class thereof. The instance can be received by the
+handler and can carry additional information about the exceptional condition.
+
+Exceptions can also be identified by strings, in which case the
+:keyword:`except` clause is selected by object identity. An arbitrary value can
+be raised along with the identifying string which can be passed to the handler.
+
+.. warning::
+
+ Messages to exceptions are not part of the Python API. Their contents may
+ change from one version of Python to the next without warning and should not be
+ relied on by code which will run under multiple versions of the interpreter.
+
+See also the description of the :keyword:`try` statement in section :ref:`try`
+and :keyword:`raise` statement in section :ref:`raise`.
+
+.. rubric:: Footnotes
+
+.. [#] This limitation occurs because the code that is executed by these operations is
+ not available at the time the module is compiled.
+
diff --git a/Doc/reference/expressions.rst b/Doc/reference/expressions.rst
new file mode 100644
index 0000000000..28c1406eeb
--- /dev/null
+++ b/Doc/reference/expressions.rst
@@ -0,0 +1,1283 @@
+
+.. _expressions:
+
+***********
+Expressions
+***********
+
+.. index:: single: expression
+
+This chapter explains the meaning of the elements of expressions in Python.
+
+.. index:: single: BNF
+
+**Syntax Notes:** In this and the following chapters, extended BNF notation will
+be used to describe syntax, not lexical analysis. When (one alternative of) a
+syntax rule has the form
+
+.. productionlist:: *
+ name: `othername`
+
+.. index:: single: syntax
+
+and no semantics are given, the semantics of this form of ``name`` are the same
+as for ``othername``.
+
+
+.. _conversions:
+
+Arithmetic conversions
+======================
+
+.. index:: pair: arithmetic; conversion
+
+.. XXX no coercion rules are documented anymore
+
+When a description of an arithmetic operator below uses the phrase "the numeric
+arguments are converted to a common type," the arguments are coerced using the
+coercion rules. If both arguments are standard
+numeric types, the following coercions are applied:
+
+* If either argument is a complex number, the other is converted to complex;
+
+* otherwise, if either argument is a floating point number, the other is
+ converted to floating point;
+
+* otherwise, if either argument is a long integer, the other is converted to
+ long integer;
+
+* otherwise, both must be plain integers and no conversion is necessary.
+
+Some additional rules apply for certain operators (e.g., a string left argument
+to the '%' operator). Extensions can define their own coercions.
+
+
+.. _atoms:
+
+Atoms
+=====
+
+.. index:: single: atom
+
+Atoms are the most basic elements of expressions. The simplest atoms are
+identifiers or literals. Forms enclosed in reverse quotes or in parentheses,
+brackets or braces are also categorized syntactically as atoms. The syntax for
+atoms is:
+
+.. productionlist::
+ atom: `identifier` | `literal` | `enclosure`
+ enclosure: `parenth_form` | `list_display`
+ : | `generator_expression` | `dict_display`
+ : | `string_conversion` | `yield_atom`
+
+
+.. _atom-identifiers:
+
+Identifiers (Names)
+-------------------
+
+.. index::
+ single: name
+ single: identifier
+
+An identifier occurring as an atom is a name. See section :ref:`identifiers`
+for lexical definition and section :ref:`naming` for documentation of naming and
+binding.
+
+.. index:: exception: NameError
+
+When the name is bound to an object, evaluation of the atom yields that object.
+When a name is not bound, an attempt to evaluate it raises a :exc:`NameError`
+exception.
+
+.. index::
+ pair: name; mangling
+ pair: private; names
+
+**Private name mangling:** When an identifier that textually occurs in a class
+definition begins with two or more underscore characters and does not end in two
+or more underscores, it is considered a :dfn:`private name` of that class.
+Private names are transformed to a longer form before code is generated for
+them. The transformation inserts the class name in front of the name, with
+leading underscores removed, and a single underscore inserted in front of the
+class name. For example, the identifier ``__spam`` occurring in a class named
+``Ham`` will be transformed to ``_Ham__spam``. This transformation is
+independent of the syntactical context in which the identifier is used. If the
+transformed name is extremely long (longer than 255 characters), implementation
+defined truncation may happen. If the class name consists only of underscores,
+no transformation is done.
+
+.. %
+.. %
+
+
+.. _atom-literals:
+
+Literals
+--------
+
+.. index:: single: literal
+
+Python supports string literals and various numeric literals:
+
+.. productionlist::
+ literal: `stringliteral` | `integer` | `longinteger`
+ : | `floatnumber` | `imagnumber`
+
+Evaluation of a literal yields an object of the given type (string, integer,
+long integer, floating point number, complex number) with the given value. The
+value may be approximated in the case of floating point and imaginary (complex)
+literals. See section :ref:`literals` for details.
+
+.. index::
+ triple: immutable; data; type
+ pair: immutable; object
+
+All literals correspond to immutable data types, and hence the object's identity
+is less important than its value. Multiple evaluations of literals with the
+same value (either the same occurrence in the program text or a different
+occurrence) may obtain the same object or a different object with the same
+value.
+
+
+.. _parenthesized:
+
+Parenthesized forms
+-------------------
+
+.. index:: single: parenthesized form
+
+A parenthesized form is an optional expression list enclosed in parentheses:
+
+.. productionlist::
+ parenth_form: "(" [`expression_list`] ")"
+
+A parenthesized expression list yields whatever that expression list yields: if
+the list contains at least one comma, it yields a tuple; otherwise, it yields
+the single expression that makes up the expression list.
+
+.. index:: pair: empty; tuple
+
+An empty pair of parentheses yields an empty tuple object. Since tuples are
+immutable, the rules for literals apply (i.e., two occurrences of the empty
+tuple may or may not yield the same object).
+
+.. index::
+ single: comma
+ pair: tuple; display
+
+Note that tuples are not formed by the parentheses, but rather by use of the
+comma operator. The exception is the empty tuple, for which parentheses *are*
+required --- allowing unparenthesized "nothing" in expressions would cause
+ambiguities and allow common typos to pass uncaught.
+
+
+.. _lists:
+
+List displays
+-------------
+
+.. index::
+ pair: list; display
+ pair: list; comprehensions
+
+A list display is a possibly empty series of expressions enclosed in square
+brackets:
+
+.. productionlist::
+ list_display: "[" [`expression_list` | `list_comprehension`] "]"
+ list_comprehension: `expression` `list_for`
+ list_for: "for" `target_list` "in" `old_expression_list` [`list_iter`]
+ old_expression_list: `old_expression` [("," `old_expression`)+ [","]]
+ list_iter: `list_for` | `list_if`
+ list_if: "if" `old_expression` [`list_iter`]
+
+.. index::
+ pair: list; comprehensions
+ object: list
+ pair: empty; list
+
+A list display yields a new list object. Its contents are specified by
+providing either a list of expressions or a list comprehension. When a
+comma-separated list of expressions is supplied, its elements are evaluated from
+left to right and placed into the list object in that order. When a list
+comprehension is supplied, it consists of a single expression followed by at
+least one :keyword:`for` clause and zero or more :keyword:`for` or :keyword:`if`
+clauses. In this case, the elements of the new list are those that would be
+produced by considering each of the :keyword:`for` or :keyword:`if` clauses a
+block, nesting from left to right, and evaluating the expression to produce a
+list element each time the innermost block is reached [#]_.
+
+
+.. _genexpr:
+
+Generator expressions
+---------------------
+
+.. index:: pair: generator; expression
+
+A generator expression is a compact generator notation in parentheses:
+
+.. productionlist::
+ generator_expression: "(" `expression` `genexpr_for` ")"
+ genexpr_for: "for" `target_list` "in" `or_test` [`genexpr_iter`]
+ genexpr_iter: `genexpr_for` | `genexpr_if`
+ genexpr_if: "if" `old_expression` [`genexpr_iter`]
+
+.. index:: object: generator
+
+A generator expression yields a new generator object. It consists of a single
+expression followed by at least one :keyword:`for` clause and zero or more
+:keyword:`for` or :keyword:`if` clauses. The iterating values of the new
+generator are those that would be produced by considering each of the
+:keyword:`for` or :keyword:`if` clauses a block, nesting from left to right, and
+evaluating the expression to yield a value that is reached the innermost block
+for each iteration.
+
+Variables used in the generator expression are evaluated lazily when the
+:meth:`__next__` method is called for generator object (in the same fashion as
+normal generators). However, the leftmost :keyword:`for` clause is immediately
+evaluated so that error produced by it can be seen before any other possible
+error in the code that handles the generator expression. Subsequent
+:keyword:`for` clauses cannot be evaluated immediately since they may depend on
+the previous :keyword:`for` loop. For example: ``(x*y for x in range(10) for y
+in bar(x))``.
+
+The parentheses can be omitted on calls with only one argument. See section
+:ref:`calls` for the detail.
+
+
+.. _dict:
+
+Dictionary displays
+-------------------
+
+.. index:: pair: dictionary; display
+
+.. index::
+ single: key
+ single: datum
+ single: key/datum pair
+
+A dictionary display is a possibly empty series of key/datum pairs enclosed in
+curly braces:
+
+.. productionlist::
+ dict_display: "{" [`key_datum_list`] "}"
+ key_datum_list: `key_datum` ("," `key_datum`)* [","]
+ key_datum: `expression` ":" `expression`
+
+.. index:: object: dictionary
+
+A dictionary display yields a new dictionary object.
+
+The key/datum pairs are evaluated from left to right to define the entries of
+the dictionary: each key object is used as a key into the dictionary to store
+the corresponding datum.
+
+.. index:: pair: immutable; object
+
+Restrictions on the types of the key values are listed earlier in section
+:ref:`types`. (To summarize, the key type should be hashable, which excludes
+all mutable objects.) Clashes between duplicate keys are not detected; the last
+datum (textually rightmost in the display) stored for a given key value
+prevails.
+
+
+.. _yieldexpr:
+
+Yield expressions
+-----------------
+
+.. index::
+ keyword: yield
+ pair: yield; expression
+ pair: generator; function
+
+.. productionlist::
+ yield_atom: "(" `yield_expression` ")"
+ yield_expression: "yield" [`expression_list`]
+
+.. versionadded:: 2.5
+
+The :keyword:`yield` expression is only used when defining a generator function,
+and can only be used in the body of a function definition. Using a
+:keyword:`yield` expression in a function definition is sufficient to cause that
+definition to create a generator function instead of a normal function.
+
+When a generator function is called, it returns an iterator known as a
+generator. That generator then controls the execution of a generator function.
+The execution starts when one of the generator's methods is called. At that
+time, the execution proceeds to the first :keyword:`yield` expression, where it
+is suspended again, returning the value of :token:`expression_list` to
+generator's caller. By suspended we mean that all local state is retained,
+including the current bindings of local variables, the instruction pointer, and
+the internal evaluation stack. When the execution is resumed by calling one of
+the generator's methods, the function can proceed exactly as if the
+:keyword:`yield` expression was just another external call. The value of the
+:keyword:`yield` expression after resuming depends on the method which resumed
+the execution.
+
+.. index:: single: coroutine
+
+All of this makes generator functions quite similar to coroutines; they yield
+multiple times, they have more than one entry point and their execution can be
+suspended. The only difference is that a generator function cannot control
+where should the execution continue after it yields; the control is always
+transfered to the generator's caller.
+
+.. index:: object: generator
+
+The following generator's methods can be used to control the execution of a
+generator function:
+
+.. index:: exception: StopIteration
+
+
+.. method:: generator.next()
+
+ Starts the execution of a generator function or resumes it at the last executed
+ :keyword:`yield` expression. When a generator function is resumed with a
+ :meth:`next` method, the current :keyword:`yield` expression always evaluates to
+ :const:`None`. The execution then continues to the next :keyword:`yield`
+ expression, where the generator is suspended again, and the value of the
+ :token:`expression_list` is returned to :meth:`next`'s caller. If the generator
+ exits without yielding another value, a :exc:`StopIteration` exception is
+ raised.
+
+
+.. method:: generator.send(value)
+
+ Resumes the execution and "sends" a value into the generator function. The
+ ``value`` argument becomes the result of the current :keyword:`yield`
+ expression. The :meth:`send` method returns the next value yielded by the
+ generator, or raises :exc:`StopIteration` if the generator exits without
+ yielding another value. When :meth:`send` is called to start the generator, it
+ must be called with :const:`None` as the argument, because there is no
+ :keyword:`yield` expression that could receieve the value.
+
+
+.. method:: generator.throw(type[, value[, traceback]])
+
+ Raises an exception of type ``type`` at the point where generator was paused,
+ and returns the next value yielded by the generator function. If the generator
+ exits without yielding another value, a :exc:`StopIteration` exception is
+ raised. If the generator function does not catch the passed-in exception, or
+ raises a different exception, then that exception propagates to the caller.
+
+.. index:: exception: GeneratorExit
+
+
+.. method:: generator.close()
+
+ Raises a :exc:`GeneratorExit` at the point where the generator function was
+ paused. If the generator function then raises :exc:`StopIteration` (by exiting
+ normally, or due to already being closed) or :exc:`GeneratorExit` (by not
+ catching the exception), close returns to its caller. If the generator yields a
+ value, a :exc:`RuntimeError` is raised. If the generator raises any other
+ exception, it is propagated to the caller. :meth:`close` does nothing if the
+ generator has already exited due to an exception or normal exit.
+
+Here is a simple example that demonstrates the behavior of generators and
+generator functions::
+
+ >>> def echo(value=None):
+ ... print "Execution starts when 'next()' is called for the first time."
+ ... try:
+ ... while True:
+ ... try:
+ ... value = (yield value)
+ ... except GeneratorExit:
+ ... # never catch GeneratorExit
+ ... raise
+ ... except Exception, e:
+ ... value = e
+ ... finally:
+ ... print "Don't forget to clean up when 'close()' is called."
+ ...
+ >>> generator = echo(1)
+ >>> print generator.next()
+ Execution starts when 'next()' is called for the first time.
+ 1
+ >>> print generator.next()
+ None
+ >>> print generator.send(2)
+ 2
+ >>> generator.throw(TypeError, "spam")
+ TypeError('spam',)
+ >>> generator.close()
+ Don't forget to clean up when 'close()' is called.
+
+
+.. seealso::
+
+ :pep:`0342` - Coroutines via Enhanced Generators
+ The proposal to enhance the API and syntax of generators, making them usable as
+ simple coroutines.
+
+
+.. _primaries:
+
+Primaries
+=========
+
+.. index:: single: primary
+
+Primaries represent the most tightly bound operations of the language. Their
+syntax is:
+
+.. productionlist::
+ primary: `atom` | `attributeref` | `subscription` | `slicing` | `call`
+
+
+.. _attribute-references:
+
+Attribute references
+--------------------
+
+.. index:: pair: attribute; reference
+
+An attribute reference is a primary followed by a period and a name:
+
+.. productionlist::
+ attributeref: `primary` "." `identifier`
+
+.. index::
+ exception: AttributeError
+ object: module
+ object: list
+
+The primary must evaluate to an object of a type that supports attribute
+references, e.g., a module, list, or an instance. This object is then asked to
+produce the attribute whose name is the identifier. If this attribute is not
+available, the exception :exc:`AttributeError` is raised. Otherwise, the type
+and value of the object produced is determined by the object. Multiple
+evaluations of the same attribute reference may yield different objects.
+
+
+.. _subscriptions:
+
+Subscriptions
+-------------
+
+.. index:: single: subscription
+
+.. index::
+ object: sequence
+ object: mapping
+ object: string
+ object: tuple
+ object: list
+ object: dictionary
+ pair: sequence; item
+
+A subscription selects an item of a sequence (string, tuple or list) or mapping
+(dictionary) object:
+
+.. productionlist::
+ subscription: `primary` "[" `expression_list` "]"
+
+The primary must evaluate to an object of a sequence or mapping type.
+
+If the primary is a mapping, the expression list must evaluate to an object
+whose value is one of the keys of the mapping, and the subscription selects the
+value in the mapping that corresponds to that key. (The expression list is a
+tuple except if it has exactly one item.)
+
+If the primary is a sequence, the expression (list) must evaluate to a plain
+integer. If this value is negative, the length of the sequence is added to it
+(so that, e.g., ``x[-1]`` selects the last item of ``x``.) The resulting value
+must be a nonnegative integer less than the number of items in the sequence, and
+the subscription selects the item whose index is that value (counting from
+zero).
+
+.. index::
+ single: character
+ pair: string; item
+
+A string's items are characters. A character is not a separate data type but a
+string of exactly one character.
+
+
+.. _slicings:
+
+Slicings
+--------
+
+.. index::
+ single: slicing
+ single: slice
+
+.. index::
+ object: sequence
+ object: string
+ object: tuple
+ object: list
+
+A slicing selects a range of items in a sequence object (e.g., a string, tuple
+or list). Slicings may be used as expressions or as targets in assignment or
+:keyword:`del` statements. The syntax for a slicing:
+
+.. productionlist::
+ slicing: `simple_slicing` | `extended_slicing`
+ simple_slicing: `primary` "[" `short_slice` "]"
+ extended_slicing: `primary` "[" `slice_list` "]"
+ slice_list: `slice_item` ("," `slice_item`)* [","]
+ slice_item: `expression` | `proper_slice` | `ellipsis`
+ proper_slice: `short_slice` | `long_slice`
+ short_slice: [`lower_bound`] ":" [`upper_bound`]
+ long_slice: `short_slice` ":" [`stride`]
+ lower_bound: `expression`
+ upper_bound: `expression`
+ stride: `expression`
+ ellipsis: "..."
+
+.. index:: pair: extended; slicing
+
+There is ambiguity in the formal syntax here: anything that looks like an
+expression list also looks like a slice list, so any subscription can be
+interpreted as a slicing. Rather than further complicating the syntax, this is
+disambiguated by defining that in this case the interpretation as a subscription
+takes priority over the interpretation as a slicing (this is the case if the
+slice list contains no proper slice nor ellipses). Similarly, when the slice
+list has exactly one short slice and no trailing comma, the interpretation as a
+simple slicing takes priority over that as an extended slicing.
+
+The semantics for a simple slicing are as follows. The primary must evaluate to
+a sequence object. The lower and upper bound expressions, if present, must
+evaluate to plain integers; defaults are zero and the ``sys.maxint``,
+respectively. If either bound is negative, the sequence's length is added to
+it. The slicing now selects all items with index *k* such that ``i <= k < j``
+where *i* and *j* are the specified lower and upper bounds. This may be an
+empty sequence. It is not an error if *i* or *j* lie outside the range of valid
+indexes (such items don't exist so they aren't selected).
+
+.. index::
+ single: start (slice object attribute)
+ single: stop (slice object attribute)
+ single: step (slice object attribute)
+
+The semantics for an extended slicing are as follows. The primary must evaluate
+to a mapping object, and it is indexed with a key that is constructed from the
+slice list, as follows. If the slice list contains at least one comma, the key
+is a tuple containing the conversion of the slice items; otherwise, the
+conversion of the lone slice item is the key. The conversion of a slice item
+that is an expression is that expression. The conversion of a proper slice is a
+slice object (see section :ref:`types`) whose :attr:`start`, :attr:`stop` and
+:attr:`step` attributes are the values of the expressions given as lower bound,
+upper bound and stride, respectively, substituting ``None`` for missing
+expressions.
+
+
+.. _calls:
+
+Calls
+-----
+
+.. index:: single: call
+
+.. index:: object: callable
+
+A call calls a callable object (e.g., a function) with a possibly empty series
+of arguments:
+
+.. productionlist::
+ call: `primary` "(" [`argument_list` [","]
+ : | `expression` `genexpr_for`] ")"
+ argument_list: `positional_arguments` ["," `keyword_arguments`]
+ : ["," "*" `expression`]
+ : ["," "**" `expression`]
+ : | `keyword_arguments` ["," "*" `expression`]
+ : ["," "**" `expression`]
+ : | "*" `expression` ["," "**" `expression`]
+ : | "**" `expression`
+ positional_arguments: `expression` ("," `expression`)*
+ keyword_arguments: `keyword_item` ("," `keyword_item`)*
+ keyword_item: `identifier` "=" `expression`
+
+A trailing comma may be present after the positional and keyword arguments but
+does not affect the semantics.
+
+The primary must evaluate to a callable object (user-defined functions, built-in
+functions, methods of built-in objects, class objects, methods of class
+instances, and certain class instances themselves are callable; extensions may
+define additional callable object types). All argument expressions are
+evaluated before the call is attempted. Please refer to section :ref:`function`
+for the syntax of formal parameter lists.
+
+If keyword arguments are present, they are first converted to positional
+arguments, as follows. First, a list of unfilled slots is created for the
+formal parameters. If there are N positional arguments, they are placed in the
+first N slots. Next, for each keyword argument, the identifier is used to
+determine the corresponding slot (if the identifier is the same as the first
+formal parameter name, the first slot is used, and so on). If the slot is
+already filled, a :exc:`TypeError` exception is raised. Otherwise, the value of
+the argument is placed in the slot, filling it (even if the expression is
+``None``, it fills the slot). When all arguments have been processed, the slots
+that are still unfilled are filled with the corresponding default value from the
+function definition. (Default values are calculated, once, when the function is
+defined; thus, a mutable object such as a list or dictionary used as default
+value will be shared by all calls that don't specify an argument value for the
+corresponding slot; this should usually be avoided.) If there are any unfilled
+slots for which no default value is specified, a :exc:`TypeError` exception is
+raised. Otherwise, the list of filled slots is used as the argument list for
+the call.
+
+If there are more positional arguments than there are formal parameter slots, a
+:exc:`TypeError` exception is raised, unless a formal parameter using the syntax
+``*identifier`` is present; in this case, that formal parameter receives a tuple
+containing the excess positional arguments (or an empty tuple if there were no
+excess positional arguments).
+
+If any keyword argument does not correspond to a formal parameter name, a
+:exc:`TypeError` exception is raised, unless a formal parameter using the syntax
+``**identifier`` is present; in this case, that formal parameter receives a
+dictionary containing the excess keyword arguments (using the keywords as keys
+and the argument values as corresponding values), or a (new) empty dictionary if
+there were no excess keyword arguments.
+
+If the syntax ``*expression`` appears in the function call, ``expression`` must
+evaluate to a sequence. Elements from this sequence are treated as if they were
+additional positional arguments; if there are postional arguments *x1*,...,*xN*
+, and ``expression`` evaluates to a sequence *y1*,...,*yM*, this is equivalent
+to a call with M+N positional arguments *x1*,...,*xN*,*y1*,...,*yM*.
+
+A consequence of this is that although the ``*expression`` syntax appears
+*after* any keyword arguments, it is processed *before* the keyword arguments
+(and the ``**expression`` argument, if any -- see below). So::
+
+ >>> def f(a, b):
+ ... print a, b
+ ...
+ >>> f(b=1, *(2,))
+ 2 1
+ >>> f(a=1, *(2,))
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: f() got multiple values for keyword argument 'a'
+ >>> f(1, *(2,))
+ 1 2
+
+It is unusual for both keyword arguments and the ``*expression`` syntax to be
+used in the same call, so in practice this confusion does not arise.
+
+If the syntax ``**expression`` appears in the function call, ``expression`` must
+evaluate to a mapping, the contents of which are treated as additional keyword
+arguments. In the case of a keyword appearing in both ``expression`` and as an
+explicit keyword argument, a :exc:`TypeError` exception is raised.
+
+Formal parameters using the syntax ``*identifier`` or ``**identifier`` cannot be
+used as positional argument slots or as keyword argument names.
+
+A call always returns some value, possibly ``None``, unless it raises an
+exception. How this value is computed depends on the type of the callable
+object.
+
+If it is---
+
+a user-defined function:
+ .. index::
+ pair: function; call
+ triple: user-defined; function; call
+ object: user-defined function
+ object: function
+
+ The code block for the function is executed, passing it the argument list. The
+ first thing the code block will do is bind the formal parameters to the
+ arguments; this is described in section :ref:`function`. When the code block
+ executes a :keyword:`return` statement, this specifies the return value of the
+ function call.
+
+a built-in function or method:
+ .. index::
+ pair: function; call
+ pair: built-in function; call
+ pair: method; call
+ pair: built-in method; call
+ object: built-in method
+ object: built-in function
+ object: method
+ object: function
+
+ The result is up to the interpreter; see :ref:`built-in-funcs` for the
+ descriptions of built-in functions and methods.
+
+a class object:
+ .. index::
+ object: class
+ pair: class object; call
+
+ A new instance of that class is returned.
+
+a class instance method:
+ .. index::
+ object: class instance
+ object: instance
+ pair: class instance; call
+
+ The corresponding user-defined function is called, with an argument list that is
+ one longer than the argument list of the call: the instance becomes the first
+ argument.
+
+a class instance:
+ .. index::
+ pair: instance; call
+ single: __call__() (object method)
+
+ The class must define a :meth:`__call__` method; the effect is then the same as
+ if that method was called.
+
+
+.. _power:
+
+The power operator
+==================
+
+The power operator binds more tightly than unary operators on its left; it binds
+less tightly than unary operators on its right. The syntax is:
+
+.. productionlist::
+ power: `primary` ["**" `u_expr`]
+
+Thus, in an unparenthesized sequence of power and unary operators, the operators
+are evaluated from right to left (this does not constrain the evaluation order
+for the operands).
+
+The power operator has the same semantics as the built-in :func:`pow` function,
+when called with two arguments: it yields its left argument raised to the power
+of its right argument. The numeric arguments are first converted to a common
+type. The result type is that of the arguments after coercion.
+
+With mixed operand types, the coercion rules for binary arithmetic operators
+apply. For int and long int operands, the result has the same type as the
+operands (after coercion) unless the second argument is negative; in that case,
+all arguments are converted to float and a float result is delivered. For
+example, ``10**2`` returns ``100``, but ``10**-2`` returns ``0.01``. (This last
+feature was added in Python 2.2. In Python 2.1 and before, if both arguments
+were of integer types and the second argument was negative, an exception was
+raised).
+
+Raising ``0.0`` to a negative power results in a :exc:`ZeroDivisionError`.
+Raising a negative number to a fractional power results in a :exc:`ValueError`.
+
+
+.. _unary:
+
+Unary arithmetic operations
+===========================
+
+.. index::
+ triple: unary; arithmetic; operation
+ triple: unary; bit-wise; operation
+
+All unary arithmetic (and bit-wise) operations have the same priority:
+
+.. productionlist::
+ u_expr: `power` | "-" `u_expr` | "+" `u_expr` | "~" `u_expr`
+
+.. index::
+ single: negation
+ single: minus
+
+The unary ``-`` (minus) operator yields the negation of its numeric argument.
+
+.. index:: single: plus
+
+The unary ``+`` (plus) operator yields its numeric argument unchanged.
+
+.. index:: single: inversion
+
+The unary ``~`` (invert) operator yields the bit-wise inversion of its plain or
+long integer argument. The bit-wise inversion of ``x`` is defined as
+``-(x+1)``. It only applies to integral numbers.
+
+.. index:: exception: TypeError
+
+In all three cases, if the argument does not have the proper type, a
+:exc:`TypeError` exception is raised.
+
+
+.. _binary:
+
+Binary arithmetic operations
+============================
+
+.. index:: triple: binary; arithmetic; operation
+
+The binary arithmetic operations have the conventional priority levels. Note
+that some of these operations also apply to certain non-numeric types. Apart
+from the power operator, there are only two levels, one for multiplicative
+operators and one for additive operators:
+
+.. productionlist::
+ m_expr: `u_expr` | `m_expr` "*" `u_expr` | `m_expr` "//" `u_expr` | `m_expr` "/" `u_expr`
+ : | `m_expr` "%" `u_expr`
+ a_expr: `m_expr` | `a_expr` "+" `m_expr` | `a_expr` "-" `m_expr`
+
+.. index:: single: multiplication
+
+The ``*`` (multiplication) operator yields the product of its arguments. The
+arguments must either both be numbers, or one argument must be an integer (plain
+or long) and the other must be a sequence. In the former case, the numbers are
+converted to a common type and then multiplied together. In the latter case,
+sequence repetition is performed; a negative repetition factor yields an empty
+sequence.
+
+.. index::
+ exception: ZeroDivisionError
+ single: division
+
+The ``/`` (division) and ``//`` (floor division) operators yield the quotient of
+their arguments. The numeric arguments are first converted to a common type.
+Plain or long integer division yields an integer of the same type; the result is
+that of mathematical division with the 'floor' function applied to the result.
+Division by zero raises the :exc:`ZeroDivisionError` exception.
+
+.. index:: single: modulo
+
+The ``%`` (modulo) operator yields the remainder from the division of the first
+argument by the second. The numeric arguments are first converted to a common
+type. A zero right argument raises the :exc:`ZeroDivisionError` exception. The
+arguments may be floating point numbers, e.g., ``3.14%0.7`` equals ``0.34``
+(since ``3.14`` equals ``4*0.7 + 0.34``.) The modulo operator always yields a
+result with the same sign as its second operand (or zero); the absolute value of
+the result is strictly smaller than the absolute value of the second operand
+[#]_.
+
+The integer division and modulo operators are connected by the following
+identity: ``x == (x/y)*y + (x%y)``. Integer division and modulo are also
+connected with the built-in function :func:`divmod`: ``divmod(x, y) == (x/y,
+x%y)``. These identities don't hold for floating point numbers; there similar
+identities hold approximately where ``x/y`` is replaced by ``floor(x/y)`` or
+``floor(x/y) - 1`` [#]_.
+
+In addition to performing the modulo operation on numbers, the ``%`` operator is
+also overloaded by string and unicode objects to perform string formatting (also
+known as interpolation). The syntax for string formatting is described in the
+Python Library Reference, section :ref:`string-formatting`.
+
+The floor division operator, the modulo operator, and the :func:`divmod`
+function are not defined for complex numbers. Instead, convert to a
+floating point number using the :func:`abs` function if appropriate.
+
+.. index:: single: addition
+
+The ``+`` (addition) operator yields the sum of its arguments. The arguments
+must either both be numbers or both sequences of the same type. In the former
+case, the numbers are converted to a common type and then added together. In
+the latter case, the sequences are concatenated.
+
+.. index:: single: subtraction
+
+The ``-`` (subtraction) operator yields the difference of its arguments. The
+numeric arguments are first converted to a common type.
+
+
+.. _shifting:
+
+Shifting operations
+===================
+
+.. index:: pair: shifting; operation
+
+The shifting operations have lower priority than the arithmetic operations:
+
+.. productionlist::
+ shift_expr: `a_expr` | `shift_expr` ( "<<" | ">>" ) `a_expr`
+
+These operators accept plain or long integers as arguments. The arguments are
+converted to a common type. They shift the first argument to the left or right
+by the number of bits given by the second argument.
+
+.. index:: exception: ValueError
+
+A right shift by *n* bits is defined as division by ``pow(2,n)``. A left shift
+by *n* bits is defined as multiplication with ``pow(2,n)``; for plain integers
+there is no overflow check so in that case the operation drops bits and flips
+the sign if the result is not less than ``pow(2,31)`` in absolute value.
+Negative shift counts raise a :exc:`ValueError` exception.
+
+
+.. _bitwise:
+
+Binary bit-wise operations
+==========================
+
+.. index:: triple: binary; bit-wise; operation
+
+Each of the three bitwise operations has a different priority level:
+
+.. productionlist::
+ and_expr: `shift_expr` | `and_expr` "&" `shift_expr`
+ xor_expr: `and_expr` | `xor_expr` "^" `and_expr`
+ or_expr: `xor_expr` | `or_expr` "|" `xor_expr`
+
+.. index:: pair: bit-wise; and
+
+The ``&`` operator yields the bitwise AND of its arguments, which must be plain
+or long integers. The arguments are converted to a common type.
+
+.. index::
+ pair: bit-wise; xor
+ pair: exclusive; or
+
+The ``^`` operator yields the bitwise XOR (exclusive OR) of its arguments, which
+must be plain or long integers. The arguments are converted to a common type.
+
+.. index::
+ pair: bit-wise; or
+ pair: inclusive; or
+
+The ``|`` operator yields the bitwise (inclusive) OR of its arguments, which
+must be plain or long integers. The arguments are converted to a common type.
+
+
+.. _comparisons:
+
+Comparisons
+===========
+
+.. index:: single: comparison
+
+.. index:: pair: C; language
+
+Unlike C, all comparison operations in Python have the same priority, which is
+lower than that of any arithmetic, shifting or bitwise operation. Also unlike
+C, expressions like ``a < b < c`` have the interpretation that is conventional
+in mathematics:
+
+.. productionlist::
+ comparison: `or_expr` ( `comp_operator` `or_expr` )*
+ comp_operator: "<" | ">" | "==" | ">=" | "<=" | "!="
+ : | "is" ["not"] | ["not"] "in"
+
+Comparisons yield boolean values: ``True`` or ``False``.
+
+.. index:: pair: chaining; comparisons
+
+Comparisons can be chained arbitrarily, e.g., ``x < y <= z`` is equivalent to
+``x < y and y <= z``, except that ``y`` is evaluated only once (but in both
+cases ``z`` is not evaluated at all when ``x < y`` is found to be false).
+
+Formally, if *a*, *b*, *c*, ..., *y*, *z* are expressions and *opa*, *opb*, ...,
+*opy* are comparison operators, then *a opa b opb c* ...*y opy z* is equivalent
+to *a opa b* :keyword:`and` *b opb c* :keyword:`and` ... *y opy z*, except that
+each expression is evaluated at most once.
+
+Note that *a opa b opb c* doesn't imply any kind of comparison between *a* and
+*c*, so that, e.g., ``x < y > z`` is perfectly legal (though perhaps not
+pretty).
+
+The operators ``<``, ``>``, ``==``, ``>=``, ``<=``, and ``!=`` compare the
+values of two objects. The objects need not have the same type. If both are
+numbers, they are converted to a common type. Otherwise, objects of different
+types *always* compare unequal, and are ordered consistently but arbitrarily.
+You can control comparison behavior of objects of non-builtin types by defining
+a ``__cmp__`` method or rich comparison methods like ``__gt__``, described in
+section :ref:`specialnames`.
+
+(This unusual definition of comparison was used to simplify the definition of
+operations like sorting and the :keyword:`in` and :keyword:`not in` operators.
+In the future, the comparison rules for objects of different types are likely to
+change.)
+
+Comparison of objects of the same type depends on the type:
+
+* Numbers are compared arithmetically.
+
+* Strings are compared lexicographically using the numeric equivalents (the
+ result of the built-in function :func:`ord`) of their characters. Unicode and
+ 8-bit strings are fully interoperable in this behavior.
+
+* Tuples and lists are compared lexicographically using comparison of
+ corresponding elements. This means that to compare equal, each element must
+ compare equal and the two sequences must be of the same type and have the same
+ length.
+
+ If not equal, the sequences are ordered the same as their first differing
+ elements. For example, ``cmp([1,2,x], [1,2,y])`` returns the same as
+ ``cmp(x,y)``. If the corresponding element does not exist, the shorter sequence
+ is ordered first (for example, ``[1,2] < [1,2,3]``).
+
+* Mappings (dictionaries) compare equal if and only if their sorted (key, value)
+ lists compare equal. [#]_ Outcomes other than equality are resolved
+ consistently, but are not otherwise defined. [#]_
+
+* Most other objects of builtin types compare unequal unless they are the same
+ object; the choice whether one object is considered smaller or larger than
+ another one is made arbitrarily but consistently within one execution of a
+ program.
+
+The operators :keyword:`in` and :keyword:`not in` test for set membership. ``x
+in s`` evaluates to true if *x* is a member of the set *s*, and false otherwise.
+``x not in s`` returns the negation of ``x in s``. The set membership test has
+traditionally been bound to sequences; an object is a member of a set if the set
+is a sequence and contains an element equal to that object. However, it is
+possible for an object to support membership tests without being a sequence. In
+particular, dictionaries support membership testing as a nicer way of spelling
+``key in dict``; other mapping types may follow suit.
+
+For the list and tuple types, ``x in y`` is true if and only if there exists an
+index *i* such that ``x == y[i]`` is true.
+
+For the Unicode and string types, ``x in y`` is true if and only if *x* is a
+substring of *y*. An equivalent test is ``y.find(x) != -1``. Note, *x* and *y*
+need not be the same type; consequently, ``u'ab' in 'abc'`` will return
+``True``. Empty strings are always considered to be a substring of any other
+string, so ``"" in "abc"`` will return ``True``.
+
+.. versionchanged:: 2.3
+ Previously, *x* was required to be a string of length ``1``.
+
+For user-defined classes which define the :meth:`__contains__` method, ``x in
+y`` is true if and only if ``y.__contains__(x)`` is true.
+
+For user-defined classes which do not define :meth:`__contains__` and do define
+:meth:`__getitem__`, ``x in y`` is true if and only if there is a non-negative
+integer index *i* such that ``x == y[i]``, and all lower integer indices do not
+raise :exc:`IndexError` exception. (If any other exception is raised, it is as
+if :keyword:`in` raised that exception).
+
+.. index::
+ operator: in
+ operator: not in
+ pair: membership; test
+ object: sequence
+
+The operator :keyword:`not in` is defined to have the inverse true value of
+:keyword:`in`.
+
+.. index::
+ operator: is
+ operator: is not
+ pair: identity; test
+
+The operators :keyword:`is` and :keyword:`is not` test for object identity: ``x
+is y`` is true if and only if *x* and *y* are the same object. ``x is not y``
+yields the inverse truth value.
+
+
+.. _booleans:
+
+Boolean operations
+==================
+
+.. index::
+ pair: Conditional; expression
+ pair: Boolean; operation
+
+Boolean operations have the lowest priority of all Python operations:
+
+.. productionlist::
+ expression: `conditional_expression` | `lambda_form`
+ old_expression: `or_test` | `old_lambda_form`
+ conditional_expression: `or_test` ["if" `or_test` "else" `expression`]
+ or_test: `and_test` | `or_test` "or" `and_test`
+ and_test: `not_test` | `and_test` "and" `not_test`
+ not_test: `comparison` | "not" `not_test`
+
+In the context of Boolean operations, and also when expressions are used by
+control flow statements, the following values are interpreted as false:
+``False``, ``None``, numeric zero of all types, and empty strings and containers
+(including strings, tuples, lists, dictionaries, sets and frozensets). All
+other values are interpreted as true.
+
+.. index:: operator: not
+
+The operator :keyword:`not` yields ``True`` if its argument is false, ``False``
+otherwise.
+
+The expression ``x if C else y`` first evaluates *C* (*not* *x*); if *C* is
+true, *x* is evaluated and its value is returned; otherwise, *y* is evaluated
+and its value is returned.
+
+.. versionadded:: 2.5
+
+.. index:: operator: and
+
+The expression ``x and y`` first evaluates *x*; if *x* is false, its value is
+returned; otherwise, *y* is evaluated and the resulting value is returned.
+
+.. index:: operator: or
+
+The expression ``x or y`` first evaluates *x*; if *x* is true, its value is
+returned; otherwise, *y* is evaluated and the resulting value is returned.
+
+(Note that neither :keyword:`and` nor :keyword:`or` restrict the value and type
+they return to ``False`` and ``True``, but rather return the last evaluated
+argument. This is sometimes useful, e.g., if ``s`` is a string that should be
+replaced by a default value if it is empty, the expression ``s or 'foo'`` yields
+the desired value. Because :keyword:`not` has to invent a value anyway, it does
+not bother to return a value of the same type as its argument, so e.g., ``not
+'foo'`` yields ``False``, not ``''``.)
+
+
+.. _lambdas:
+
+Lambdas
+=======
+
+.. index::
+ pair: lambda; expression
+ pair: lambda; form
+ pair: anonymous; function
+
+.. productionlist::
+ lambda_form: "lambda" [`parameter_list`]: `expression`
+ old_lambda_form: "lambda" [`parameter_list`]: `old_expression`
+
+Lambda forms (lambda expressions) have the same syntactic position as
+expressions. They are a shorthand to create anonymous functions; the expression
+``lambda arguments: expression`` yields a function object. The unnamed object
+behaves like a function object defined with ::
+
+ def name(arguments):
+ return expression
+
+See section :ref:`function` for the syntax of parameter lists. Note that
+functions created with lambda forms cannot contain statements or annotations.
+
+.. _lambda:
+
+
+.. _exprlists:
+
+Expression lists
+================
+
+.. index:: pair: expression; list
+
+.. productionlist::
+ expression_list: `expression` ( "," `expression` )* [","]
+
+.. index:: object: tuple
+
+An expression list containing at least one comma yields a tuple. The length of
+the tuple is the number of expressions in the list. The expressions are
+evaluated from left to right.
+
+.. index:: pair: trailing; comma
+
+The trailing comma is required only to create a single tuple (a.k.a. a
+*singleton*); it is optional in all other cases. A single expression without a
+trailing comma doesn't create a tuple, but rather yields the value of that
+expression. (To create an empty tuple, use an empty pair of parentheses:
+``()``.)
+
+
+.. _evalorder:
+
+Evaluation order
+================
+
+.. index:: pair: evaluation; order
+
+Python evaluates expressions from left to right. Notice that while evaluating an
+assignment, the right-hand side is evaluated before the left-hand side.
+
+In the following lines, expressions will be evaluated in the arithmetic order of
+their suffixes::
+
+ expr1, expr2, expr3, expr4
+ (expr1, expr2, expr3, expr4)
+ {expr1: expr2, expr3: expr4}
+ expr1 + expr2 * (expr3 - expr4)
+ func(expr1, expr2, *expr3, **expr4)
+ expr3, expr4 = expr1, expr2
+
+
+.. _operator-summary:
+
+Summary
+=======
+
+.. index:: pair: operator; precedence
+
+The following table summarizes the operator precedences in Python, from lowest
+precedence (least binding) to highest precedence (most binding). Operators in
+the same box have the same precedence. Unless the syntax is explicitly given,
+operators are binary. Operators in the same box group left to right (except for
+comparisons, including tests, which all have the same precedence and chain from
+left to right --- see section :ref:`comparisons` --- and exponentiation, which
+groups from right to left).
+
++----------------------------------------------+-------------------------------------+
+| Operator | Description |
++==============================================+=====================================+
+| :keyword:`lambda` | Lambda expression |
++----------------------------------------------+-------------------------------------+
+| :keyword:`or` | Boolean OR |
++----------------------------------------------+-------------------------------------+
+| :keyword:`and` | Boolean AND |
++----------------------------------------------+-------------------------------------+
+| :keyword:`not` *x* | Boolean NOT |
++----------------------------------------------+-------------------------------------+
+| :keyword:`in`, :keyword:`not` :keyword:`in` | Membership tests |
++----------------------------------------------+-------------------------------------+
+| :keyword:`is`, :keyword:`is not` | Identity tests |
++----------------------------------------------+-------------------------------------+
+| ``<``, ``<=``, ``>``, ``>=``, ``!=``, ``==`` | Comparisons |
++----------------------------------------------+-------------------------------------+
+| ``|`` | Bitwise OR |
++----------------------------------------------+-------------------------------------+
+| ``^`` | Bitwise XOR |
++----------------------------------------------+-------------------------------------+
+| ``&`` | Bitwise AND |
++----------------------------------------------+-------------------------------------+
+| ``<<``, ``>>`` | Shifts |
++----------------------------------------------+-------------------------------------+
+| ``+``, ``-`` | Addition and subtraction |
++----------------------------------------------+-------------------------------------+
+| ``*``, ``/``, ``%`` | Multiplication, division, remainder |
++----------------------------------------------+-------------------------------------+
+| ``+x``, ``-x`` | Positive, negative |
++----------------------------------------------+-------------------------------------+
+| ``~x`` | Bitwise not |
++----------------------------------------------+-------------------------------------+
+| ``**`` | Exponentiation |
++----------------------------------------------+-------------------------------------+
+| ``x.attribute`` | Attribute reference |
++----------------------------------------------+-------------------------------------+
+| ``x[index]`` | Subscription |
++----------------------------------------------+-------------------------------------+
+| ``x[index:index]`` | Slicing |
++----------------------------------------------+-------------------------------------+
+| ``f(arguments...)`` | Function call |
++----------------------------------------------+-------------------------------------+
+| ``(expressions...)`` | Binding or tuple display |
++----------------------------------------------+-------------------------------------+
+| ``[expressions...]`` | List display |
++----------------------------------------------+-------------------------------------+
+| ``{key:datum...}`` | Dictionary display |
++----------------------------------------------+-------------------------------------+
+
+.. rubric:: Footnotes
+
+.. [#] In Python 2.3, a list comprehension "leaks" the control variables of each
+ ``for`` it contains into the containing scope. However, this behavior is
+ deprecated, and relying on it will not work once this bug is fixed in a future
+ release
+
+.. [#] While ``abs(x%y) < abs(y)`` is true mathematically, for floats it may not be
+ true numerically due to roundoff. For example, and assuming a platform on which
+ a Python float is an IEEE 754 double-precision number, in order that ``-1e-100 %
+ 1e100`` have the same sign as ``1e100``, the computed result is ``-1e-100 +
+ 1e100``, which is numerically exactly equal to ``1e100``. Function :func:`fmod`
+ in the :mod:`math` module returns a result whose sign matches the sign of the
+ first argument instead, and so returns ``-1e-100`` in this case. Which approach
+ is more appropriate depends on the application.
+
+.. [#] If x is very close to an exact integer multiple of y, it's possible for
+ ``floor(x/y)`` to be one larger than ``(x-x%y)/y`` due to rounding. In such
+ cases, Python returns the latter result, in order to preserve that
+ ``divmod(x,y)[0] * y + x % y`` be very close to ``x``.
+
+.. [#] The implementation computes this efficiently, without constructing lists or
+ sorting.
+
+.. [#] Earlier versions of Python used lexicographic comparison of the sorted (key,
+ value) lists, but this was very expensive for the common case of comparing for
+ equality. An even earlier version of Python compared dictionaries by identity
+ only, but this caused surprises because people expected to be able to test a
+ dictionary for emptiness by comparing it to ``{}``.
+
diff --git a/Doc/reference/index.rst b/Doc/reference/index.rst
new file mode 100644
index 0000000000..18bf0537a9
--- /dev/null
+++ b/Doc/reference/index.rst
@@ -0,0 +1,30 @@
+.. _reference-index:
+
+#################################
+ The Python language reference
+#################################
+
+:Release: |version|
+:Date: |today|
+
+This reference manual describes the syntax and "core semantics" of the
+language. It is terse, but attempts to be exact and complete. The semantics of
+non-essential built-in object types and of the built-in functions and modules
+are described in :ref:`library-index`. For an informal introduction to the
+language, see :ref:`tutorial-index`. For C or C++ programmers, two additional
+manuals exist: :ref:`extending-index` describes the high-level picture of how to
+write a Python extension module, and the :ref:`c-api-index` describes the
+interfaces available to C/C++ programmers in detail.
+
+.. toctree::
+ :maxdepth: 2
+
+ introduction.rst
+ lexical_analysis.rst
+ datamodel.rst
+ executionmodel.rst
+ expressions.rst
+ simple_stmts.rst
+ compound_stmts.rst
+ toplevel_components.rst
+
diff --git a/Doc/reference/introduction.rst b/Doc/reference/introduction.rst
new file mode 100644
index 0000000000..0d53719f27
--- /dev/null
+++ b/Doc/reference/introduction.rst
@@ -0,0 +1,138 @@
+
+.. _introduction:
+
+************
+Introduction
+************
+
+This reference manual describes the Python programming language. It is not
+intended as a tutorial.
+
+While I am trying to be as precise as possible, I chose to use English rather
+than formal specifications for everything except syntax and lexical analysis.
+This should make the document more understandable to the average reader, but
+will leave room for ambiguities. Consequently, if you were coming from Mars and
+tried to re-implement Python from this document alone, you might have to guess
+things and in fact you would probably end up implementing quite a different
+language. On the other hand, if you are using Python and wonder what the precise
+rules about a particular area of the language are, you should definitely be able
+to find them here. If you would like to see a more formal definition of the
+language, maybe you could volunteer your time --- or invent a cloning machine
+:-).
+
+It is dangerous to add too many implementation details to a language reference
+document --- the implementation may change, and other implementations of the
+same language may work differently. On the other hand, there is currently only
+one Python implementation in widespread use (although alternate implementations
+exist), and its particular quirks are sometimes worth being mentioned,
+especially where the implementation imposes additional limitations. Therefore,
+you'll find short "implementation notes" sprinkled throughout the text.
+
+Every Python implementation comes with a number of built-in and standard
+modules. These are documented in :ref:`library-index`. A few built-in modules
+are mentioned when they interact in a significant way with the language
+definition.
+
+
+.. _implementations:
+
+Alternate Implementations
+=========================
+
+Though there is one Python implementation which is by far the most popular,
+there are some alternate implementations which are of particular interest to
+different audiences.
+
+Known implementations include:
+
+CPython
+ This is the original and most-maintained implementation of Python, written in C.
+ New language features generally appear here first.
+
+Jython
+ Python implemented in Java. This implementation can be used as a scripting
+ language for Java applications, or can be used to create applications using the
+ Java class libraries. It is also often used to create tests for Java libraries.
+ More information can be found at `the Jython website <http://www.jython.org/>`_.
+
+Python for .NET
+ This implementation actually uses the CPython implementation, but is a managed
+ .NET application and makes .NET libraries available. This was created by Brian
+ Lloyd. For more information, see the `Python for .NET home page
+ <http://www.zope.org/Members/Brian/PythonNet>`_.
+
+IronPython
+ An alternate Python for .NET. Unlike Python.NET, this is a complete Python
+ implementation that generates IL, and compiles Python code directly to .NET
+ assemblies. It was created by Jim Hugunin, the original creator of Jython. For
+ more information, see `the IronPython website
+ <http://workspaces.gotdotnet.com/ironpython>`_.
+
+PyPy
+ An implementation of Python written in Python; even the bytecode interpreter is
+ written in Python. This is executed using CPython as the underlying
+ interpreter. One of the goals of the project is to encourage experimentation
+ with the language itself by making it easier to modify the interpreter (since it
+ is written in Python). Additional information is available on `the PyPy
+ project's home page <http://codespeak.net/pypy/>`_.
+
+Each of these implementations varies in some way from the language as documented
+in this manual, or introduces specific information beyond what's covered in the
+standard Python documentation. Please refer to the implementation-specific
+documentation to determine what else you need to know about the specific
+implementation you're using.
+
+
+.. _notation:
+
+Notation
+========
+
+.. index::
+ single: BNF
+ single: grammar
+ single: syntax
+ single: notation
+
+The descriptions of lexical analysis and syntax use a modified BNF grammar
+notation. This uses the following style of definition:
+
+.. productionlist:: *
+ name: `lc_letter` (`lc_letter` | "_")*
+ lc_letter: "a"..."z"
+
+The first line says that a ``name`` is an ``lc_letter`` followed by a sequence
+of zero or more ``lc_letter``\ s and underscores. An ``lc_letter`` in turn is
+any of the single characters ``'a'`` through ``'z'``. (This rule is actually
+adhered to for the names defined in lexical and grammar rules in this document.)
+
+Each rule begins with a name (which is the name defined by the rule) and
+``::=``. A vertical bar (``|``) is used to separate alternatives; it is the
+least binding operator in this notation. A star (``*``) means zero or more
+repetitions of the preceding item; likewise, a plus (``+``) means one or more
+repetitions, and a phrase enclosed in square brackets (``[ ]``) means zero or
+one occurrences (in other words, the enclosed phrase is optional). The ``*``
+and ``+`` operators bind as tightly as possible; parentheses are used for
+grouping. Literal strings are enclosed in quotes. White space is only
+meaningful to separate tokens. Rules are normally contained on a single line;
+rules with many alternatives may be formatted alternatively with each line after
+the first beginning with a vertical bar.
+
+.. index::
+ single: lexical definitions
+ single: ASCII@ASCII
+
+In lexical definitions (as the example above), two more conventions are used:
+Two literal characters separated by three dots mean a choice of any single
+character in the given (inclusive) range of ASCII characters. A phrase between
+angular brackets (``<...>``) gives an informal description of the symbol
+defined; e.g., this could be used to describe the notion of 'control character'
+if needed.
+
+Even though the notation used is almost the same, there is a big difference
+between the meaning of lexical and syntactic definitions: a lexical definition
+operates on the individual characters of the input source, while a syntax
+definition operates on the stream of tokens generated by the lexical analysis.
+All uses of BNF in the next chapter ("Lexical Analysis") are lexical
+definitions; uses in subsequent chapters are syntactic definitions.
+
diff --git a/Doc/reference/lexical_analysis.rst b/Doc/reference/lexical_analysis.rst
new file mode 100644
index 0000000000..35e92cf9cb
--- /dev/null
+++ b/Doc/reference/lexical_analysis.rst
@@ -0,0 +1,758 @@
+
+.. _lexical:
+
+****************
+Lexical analysis
+****************
+
+.. index::
+ single: lexical analysis
+ single: parser
+ single: token
+
+A Python program is read by a *parser*. Input to the parser is a stream of
+*tokens*, generated by the *lexical analyzer*. This chapter describes how the
+lexical analyzer breaks a file into tokens.
+
+Python uses the 7-bit ASCII character set for program text.
+
+.. versionadded:: 2.3
+ An encoding declaration can be used to indicate that string literals and
+ comments use an encoding different from ASCII.
+
+For compatibility with older versions, Python only warns if it finds 8-bit
+characters; those warnings should be corrected by either declaring an explicit
+encoding, or using escape sequences if those bytes are binary data, instead of
+characters.
+
+The run-time character set depends on the I/O devices connected to the program
+but is generally a superset of ASCII.
+
+**Future compatibility note:** It may be tempting to assume that the character
+set for 8-bit characters is ISO Latin-1 (an ASCII superset that covers most
+western languages that use the Latin alphabet), but it is possible that in the
+future Unicode text editors will become common. These generally use the UTF-8
+encoding, which is also an ASCII superset, but with very different use for the
+characters with ordinals 128-255. While there is no consensus on this subject
+yet, it is unwise to assume either Latin-1 or UTF-8, even though the current
+implementation appears to favor Latin-1. This applies both to the source
+character set and the run-time character set.
+
+
+.. _line-structure:
+
+Line structure
+==============
+
+.. index:: single: line structure
+
+A Python program is divided into a number of *logical lines*.
+
+
+.. _logical:
+
+Logical lines
+-------------
+
+.. index::
+ single: logical line
+ single: physical line
+ single: line joining
+ single: NEWLINE token
+
+The end of a logical line is represented by the token NEWLINE. Statements
+cannot cross logical line boundaries except where NEWLINE is allowed by the
+syntax (e.g., between statements in compound statements). A logical line is
+constructed from one or more *physical lines* by following the explicit or
+implicit *line joining* rules.
+
+
+.. _physical:
+
+Physical lines
+--------------
+
+A physical line is a sequence of characters terminated by an end-of-line
+sequence. In source files, any of the standard platform line termination
+sequences can be used - the Unix form using ASCII LF (linefeed), the Windows
+form using the ASCII sequence CR LF (return followed by linefeed), or the
+Macintosh form using the ASCII CR (return) character. All of these forms can be
+used equally, regardless of platform.
+
+When embedding Python, source code strings should be passed to Python APIs using
+the standard C conventions for newline characters (the ``\n`` character,
+representing ASCII LF, is the line terminator).
+
+
+.. _comments:
+
+Comments
+--------
+
+.. index::
+ single: comment
+ single: hash character
+
+A comment starts with a hash character (``#``) that is not part of a string
+literal, and ends at the end of the physical line. A comment signifies the end
+of the logical line unless the implicit line joining rules are invoked. Comments
+are ignored by the syntax; they are not tokens.
+
+
+.. _encodings:
+
+Encoding declarations
+---------------------
+
+.. index::
+ single: source character set
+ single: encodings
+
+If a comment in the first or second line of the Python script matches the
+regular expression ``coding[=:]\s*([-\w.]+)``, this comment is processed as an
+encoding declaration; the first group of this expression names the encoding of
+the source code file. The recommended forms of this expression are ::
+
+ # -*- coding: <encoding-name> -*-
+
+which is recognized also by GNU Emacs, and ::
+
+ # vim:fileencoding=<encoding-name>
+
+which is recognized by Bram Moolenaar's VIM. In addition, if the first bytes of
+the file are the UTF-8 byte-order mark (``'\xef\xbb\xbf'``), the declared file
+encoding is UTF-8 (this is supported, among others, by Microsoft's
+:program:`notepad`).
+
+If an encoding is declared, the encoding name must be recognized by Python. The
+encoding is used for all lexical analysis, in particular to find the end of a
+string, and to interpret the contents of Unicode literals. String literals are
+converted to Unicode for syntactical analysis, then converted back to their
+original encoding before interpretation starts. The encoding declaration must
+appear on a line of its own.
+
+.. % XXX there should be a list of supported encodings.
+
+
+.. _explicit-joining:
+
+Explicit line joining
+---------------------
+
+.. index::
+ single: physical line
+ single: line joining
+ single: line continuation
+ single: backslash character
+
+Two or more physical lines may be joined into logical lines using backslash
+characters (``\``), as follows: when a physical line ends in a backslash that is
+not part of a string literal or comment, it is joined with the following forming
+a single logical line, deleting the backslash and the following end-of-line
+character. For example:
+
+.. %
+
+::
+
+ if 1900 < year < 2100 and 1 <= month <= 12 \
+ and 1 <= day <= 31 and 0 <= hour < 24 \
+ and 0 <= minute < 60 and 0 <= second < 60: # Looks like a valid date
+ return 1
+
+A line ending in a backslash cannot carry a comment. A backslash does not
+continue a comment. A backslash does not continue a token except for string
+literals (i.e., tokens other than string literals cannot be split across
+physical lines using a backslash). A backslash is illegal elsewhere on a line
+outside a string literal.
+
+
+.. _implicit-joining:
+
+Implicit line joining
+---------------------
+
+Expressions in parentheses, square brackets or curly braces can be split over
+more than one physical line without using backslashes. For example::
+
+ month_names = ['Januari', 'Februari', 'Maart', # These are the
+ 'April', 'Mei', 'Juni', # Dutch names
+ 'Juli', 'Augustus', 'September', # for the months
+ 'Oktober', 'November', 'December'] # of the year
+
+Implicitly continued lines can carry comments. The indentation of the
+continuation lines is not important. Blank continuation lines are allowed.
+There is no NEWLINE token between implicit continuation lines. Implicitly
+continued lines can also occur within triple-quoted strings (see below); in that
+case they cannot carry comments.
+
+
+.. _blank-lines:
+
+Blank lines
+-----------
+
+.. index:: single: blank line
+
+A logical line that contains only spaces, tabs, formfeeds and possibly a
+comment, is ignored (i.e., no NEWLINE token is generated). During interactive
+input of statements, handling of a blank line may differ depending on the
+implementation of the read-eval-print loop. In the standard implementation, an
+entirely blank logical line (i.e. one containing not even whitespace or a
+comment) terminates a multi-line statement.
+
+
+.. _indentation:
+
+Indentation
+-----------
+
+.. index::
+ single: indentation
+ single: whitespace
+ single: leading whitespace
+ single: space
+ single: tab
+ single: grouping
+ single: statement grouping
+
+Leading whitespace (spaces and tabs) at the beginning of a logical line is used
+to compute the indentation level of the line, which in turn is used to determine
+the grouping of statements.
+
+First, tabs are replaced (from left to right) by one to eight spaces such that
+the total number of characters up to and including the replacement is a multiple
+of eight (this is intended to be the same rule as used by Unix). The total
+number of spaces preceding the first non-blank character then determines the
+line's indentation. Indentation cannot be split over multiple physical lines
+using backslashes; the whitespace up to the first backslash determines the
+indentation.
+
+**Cross-platform compatibility note:** because of the nature of text editors on
+non-UNIX platforms, it is unwise to use a mixture of spaces and tabs for the
+indentation in a single source file. It should also be noted that different
+platforms may explicitly limit the maximum indentation level.
+
+A formfeed character may be present at the start of the line; it will be ignored
+for the indentation calculations above. Formfeed characters occurring elsewhere
+in the leading whitespace have an undefined effect (for instance, they may reset
+the space count to zero).
+
+.. index::
+ single: INDENT token
+ single: DEDENT token
+
+The indentation levels of consecutive lines are used to generate INDENT and
+DEDENT tokens, using a stack, as follows.
+
+Before the first line of the file is read, a single zero is pushed on the stack;
+this will never be popped off again. The numbers pushed on the stack will
+always be strictly increasing from bottom to top. At the beginning of each
+logical line, the line's indentation level is compared to the top of the stack.
+If it is equal, nothing happens. If it is larger, it is pushed on the stack, and
+one INDENT token is generated. If it is smaller, it *must* be one of the
+numbers occurring on the stack; all numbers on the stack that are larger are
+popped off, and for each number popped off a DEDENT token is generated. At the
+end of the file, a DEDENT token is generated for each number remaining on the
+stack that is larger than zero.
+
+Here is an example of a correctly (though confusingly) indented piece of Python
+code::
+
+ def perm(l):
+ # Compute the list of all permutations of l
+ if len(l) <= 1:
+ return [l]
+ r = []
+ for i in range(len(l)):
+ s = l[:i] + l[i+1:]
+ p = perm(s)
+ for x in p:
+ r.append(l[i:i+1] + x)
+ return r
+
+The following example shows various indentation errors::
+
+ def perm(l): # error: first line indented
+ for i in range(len(l)): # error: not indented
+ s = l[:i] + l[i+1:]
+ p = perm(l[:i] + l[i+1:]) # error: unexpected indent
+ for x in p:
+ r.append(l[i:i+1] + x)
+ return r # error: inconsistent dedent
+
+(Actually, the first three errors are detected by the parser; only the last
+error is found by the lexical analyzer --- the indentation of ``return r`` does
+not match a level popped off the stack.)
+
+
+.. _whitespace:
+
+Whitespace between tokens
+-------------------------
+
+Except at the beginning of a logical line or in string literals, the whitespace
+characters space, tab and formfeed can be used interchangeably to separate
+tokens. Whitespace is needed between two tokens only if their concatenation
+could otherwise be interpreted as a different token (e.g., ab is one token, but
+a b is two tokens).
+
+
+.. _other-tokens:
+
+Other tokens
+============
+
+Besides NEWLINE, INDENT and DEDENT, the following categories of tokens exist:
+*identifiers*, *keywords*, *literals*, *operators*, and *delimiters*. Whitespace
+characters (other than line terminators, discussed earlier) are not tokens, but
+serve to delimit tokens. Where ambiguity exists, a token comprises the longest
+possible string that forms a legal token, when read from left to right.
+
+
+.. _identifiers:
+
+Identifiers and keywords
+========================
+
+.. index::
+ single: identifier
+ single: name
+
+Identifiers (also referred to as *names*) are described by the following lexical
+definitions:
+
+.. productionlist::
+ identifier: (`letter`|"_") (`letter` | `digit` | "_")*
+ letter: `lowercase` | `uppercase`
+ lowercase: "a"..."z"
+ uppercase: "A"..."Z"
+ digit: "0"..."9"
+
+Identifiers are unlimited in length. Case is significant.
+
+
+.. _keywords:
+
+Keywords
+--------
+
+.. index::
+ single: keyword
+ single: reserved word
+
+The following identifiers are used as reserved words, or *keywords* of the
+language, and cannot be used as ordinary identifiers. They must be spelled
+exactly as written here::
+
+ and def for is raise
+ as del from lambda return
+ assert elif global not try
+ break else if or while
+ class except import pass with
+ continue finally in print yield
+
+.. versionchanged:: 2.4
+ :const:`None` became a constant and is now recognized by the compiler as a name
+ for the built-in object :const:`None`. Although it is not a keyword, you cannot
+ assign a different object to it.
+
+.. versionchanged:: 2.5
+ Both :keyword:`as` and :keyword:`with` are only recognized when the
+ ``with_statement`` future feature has been enabled. It will always be enabled in
+ Python 2.6. See section :ref:`with` for details. Note that using :keyword:`as`
+ and :keyword:`with` as identifiers will always issue a warning, even when the
+ ``with_statement`` future directive is not in effect.
+
+
+.. _id-classes:
+
+Reserved classes of identifiers
+-------------------------------
+
+Certain classes of identifiers (besides keywords) have special meanings. These
+classes are identified by the patterns of leading and trailing underscore
+characters:
+
+``_*``
+ Not imported by ``from module import *``. The special identifier ``_`` is used
+ in the interactive interpreter to store the result of the last evaluation; it is
+ stored in the :mod:`__builtin__` module. When not in interactive mode, ``_``
+ has no special meaning and is not defined. See section :ref:`import`.
+
+ .. note::
+
+ The name ``_`` is often used in conjunction with internationalization;
+ refer to the documentation for the :mod:`gettext` module for more
+ information on this convention.
+
+``__*__``
+ System-defined names. These names are defined by the interpreter and its
+ implementation (including the standard library); applications should not expect
+ to define additional names using this convention. The set of names of this
+ class defined by Python may be extended in future versions. See section
+ :ref:`specialnames`.
+
+``__*``
+ Class-private names. Names in this category, when used within the context of a
+ class definition, are re-written to use a mangled form to help avoid name
+ clashes between "private" attributes of base and derived classes. See section
+ :ref:`atom-identifiers`.
+
+
+.. _literals:
+
+Literals
+========
+
+.. index::
+ single: literal
+ single: constant
+
+Literals are notations for constant values of some built-in types.
+
+
+.. _strings:
+
+String literals
+---------------
+
+.. index:: single: string literal
+
+String literals are described by the following lexical definitions:
+
+.. index:: single: ASCII@ASCII
+
+.. productionlist::
+ stringliteral: [`stringprefix`](`shortstring` | `longstring`)
+ stringprefix: "r" | "u" | "ur" | "R" | "U" | "UR" | "Ur" | "uR"
+ shortstring: "'" `shortstringitem`* "'" | '"' `shortstringitem`* '"'
+ longstring: ""'" `longstringitem`* ""'"
+ : | '"""' `longstringitem`* '"""'
+ shortstringitem: `shortstringchar` | `escapeseq`
+ longstringitem: `longstringchar` | `escapeseq`
+ shortstringchar: <any source character except "\" or newline or the quote>
+ longstringchar: <any source character except "\">
+ escapeseq: "\" <any ASCII character>
+
+One syntactic restriction not indicated by these productions is that whitespace
+is not allowed between the :token:`stringprefix` and the rest of the string
+literal. The source character set is defined by the encoding declaration; it is
+ASCII if no encoding declaration is given in the source file; see section
+:ref:`encodings`.
+
+.. index::
+ single: triple-quoted string
+ single: Unicode Consortium
+ single: string; Unicode
+ single: raw string
+
+In plain English: String literals can be enclosed in matching single quotes
+(``'``) or double quotes (``"``). They can also be enclosed in matching groups
+of three single or double quotes (these are generally referred to as
+*triple-quoted strings*). The backslash (``\``) character is used to escape
+characters that otherwise have a special meaning, such as newline, backslash
+itself, or the quote character. String literals may optionally be prefixed with
+a letter ``'r'`` or ``'R'``; such strings are called :dfn:`raw strings` and use
+different rules for interpreting backslash escape sequences. A prefix of
+``'u'`` or ``'U'`` makes the string a Unicode string. Unicode strings use the
+Unicode character set as defined by the Unicode Consortium and ISO 10646. Some
+additional escape sequences, described below, are available in Unicode strings.
+The two prefix characters may be combined; in this case, ``'u'`` must appear
+before ``'r'``.
+
+In triple-quoted strings, unescaped newlines and quotes are allowed (and are
+retained), except that three unescaped quotes in a row terminate the string. (A
+"quote" is the character used to open the string, i.e. either ``'`` or ``"``.)
+
+.. index::
+ single: physical line
+ single: escape sequence
+ single: Standard C
+ single: C
+
+Unless an ``'r'`` or ``'R'`` prefix is present, escape sequences in strings are
+interpreted according to rules similar to those used by Standard C. The
+recognized escape sequences are:
+
++-----------------+---------------------------------+-------+
+| Escape Sequence | Meaning | Notes |
++=================+=================================+=======+
+| ``\newline`` | Ignored | |
++-----------------+---------------------------------+-------+
+| ``\\`` | Backslash (``\``) | |
++-----------------+---------------------------------+-------+
+| ``\'`` | Single quote (``'``) | |
++-----------------+---------------------------------+-------+
+| ``\"`` | Double quote (``"``) | |
++-----------------+---------------------------------+-------+
+| ``\a`` | ASCII Bell (BEL) | |
++-----------------+---------------------------------+-------+
+| ``\b`` | ASCII Backspace (BS) | |
++-----------------+---------------------------------+-------+
+| ``\f`` | ASCII Formfeed (FF) | |
++-----------------+---------------------------------+-------+
+| ``\n`` | ASCII Linefeed (LF) | |
++-----------------+---------------------------------+-------+
+| ``\N{name}`` | Character named *name* in the | |
+| | Unicode database (Unicode only) | |
++-----------------+---------------------------------+-------+
+| ``\r`` | ASCII Carriage Return (CR) | |
++-----------------+---------------------------------+-------+
+| ``\t`` | ASCII Horizontal Tab (TAB) | |
++-----------------+---------------------------------+-------+
+| ``\uxxxx`` | Character with 16-bit hex value | \(1) |
+| | *xxxx* (Unicode only) | |
++-----------------+---------------------------------+-------+
+| ``\Uxxxxxxxx`` | Character with 32-bit hex value | \(2) |
+| | *xxxxxxxx* (Unicode only) | |
++-----------------+---------------------------------+-------+
+| ``\v`` | ASCII Vertical Tab (VT) | |
++-----------------+---------------------------------+-------+
+| ``\ooo`` | Character with octal value | (3,5) |
+| | *ooo* | |
++-----------------+---------------------------------+-------+
+| ``\xhh`` | Character with hex value *hh* | (4,5) |
++-----------------+---------------------------------+-------+
+
+.. index:: single: ASCII@ASCII
+
+Notes:
+
+(1)
+ Individual code units which form parts of a surrogate pair can be encoded using
+ this escape sequence.
+
+(2)
+ Any Unicode character can be encoded this way, but characters outside the Basic
+ Multilingual Plane (BMP) will be encoded using a surrogate pair if Python is
+ compiled to use 16-bit code units (the default). Individual code units which
+ form parts of a surrogate pair can be encoded using this escape sequence.
+
+(3)
+ As in Standard C, up to three octal digits are accepted.
+
+(4)
+ Unlike in Standard C, at most two hex digits are accepted.
+
+(5)
+ In a string literal, hexadecimal and octal escapes denote the byte with the
+ given value; it is not necessary that the byte encodes a character in the source
+ character set. In a Unicode literal, these escapes denote a Unicode character
+ with the given value.
+
+.. index:: single: unrecognized escape sequence
+
+Unlike Standard C, all unrecognized escape sequences are left in the string
+unchanged, i.e., *the backslash is left in the string*. (This behavior is
+useful when debugging: if an escape sequence is mistyped, the resulting output
+is more easily recognized as broken.) It is also important to note that the
+escape sequences marked as "(Unicode only)" in the table above fall into the
+category of unrecognized escapes for non-Unicode string literals.
+
+When an ``'r'`` or ``'R'`` prefix is present, a character following a backslash
+is included in the string without change, and *all backslashes are left in the
+string*. For example, the string literal ``r"\n"`` consists of two characters:
+a backslash and a lowercase ``'n'``. String quotes can be escaped with a
+backslash, but the backslash remains in the string; for example, ``r"\""`` is a
+valid string literal consisting of two characters: a backslash and a double
+quote; ``r"\"`` is not a valid string literal (even a raw string cannot end in
+an odd number of backslashes). Specifically, *a raw string cannot end in a
+single backslash* (since the backslash would escape the following quote
+character). Note also that a single backslash followed by a newline is
+interpreted as those two characters as part of the string, *not* as a line
+continuation.
+
+When an ``'r'`` or ``'R'`` prefix is used in conjunction with a ``'u'`` or
+``'U'`` prefix, then the ``\uXXXX`` and ``\UXXXXXXXX`` escape sequences are
+processed while *all other backslashes are left in the string*. For example,
+the string literal ``ur"\u0062\n"`` consists of three Unicode characters: 'LATIN
+SMALL LETTER B', 'REVERSE SOLIDUS', and 'LATIN SMALL LETTER N'. Backslashes can
+be escaped with a preceding backslash; however, both remain in the string. As a
+result, ``\uXXXX`` escape sequences are only recognized when there are an odd
+number of backslashes.
+
+
+.. _string-catenation:
+
+String literal concatenation
+----------------------------
+
+Multiple adjacent string literals (delimited by whitespace), possibly using
+different quoting conventions, are allowed, and their meaning is the same as
+their concatenation. Thus, ``"hello" 'world'`` is equivalent to
+``"helloworld"``. This feature can be used to reduce the number of backslashes
+needed, to split long strings conveniently across long lines, or even to add
+comments to parts of strings, for example::
+
+ re.compile("[A-Za-z_]" # letter or underscore
+ "[A-Za-z0-9_]*" # letter, digit or underscore
+ )
+
+Note that this feature is defined at the syntactical level, but implemented at
+compile time. The '+' operator must be used to concatenate string expressions
+at run time. Also note that literal concatenation can use different quoting
+styles for each component (even mixing raw strings and triple quoted strings).
+
+
+.. _numbers:
+
+Numeric literals
+----------------
+
+.. index::
+ single: number
+ single: numeric literal
+ single: integer literal
+ single: plain integer literal
+ single: long integer literal
+ single: floating point literal
+ single: hexadecimal literal
+ single: octal literal
+ single: binary literal
+ single: decimal literal
+ single: imaginary literal
+ single: complex; literal
+
+There are four types of numeric literals: plain integers, long integers,
+floating point numbers, and imaginary numbers. There are no complex literals
+(complex numbers can be formed by adding a real number and an imaginary number).
+
+Note that numeric literals do not include a sign; a phrase like ``-1`` is
+actually an expression composed of the unary operator '``-``' and the literal
+``1``.
+
+
+.. _integers:
+
+Integer literals
+----------------
+
+Integer literals are described by the following lexical definitions:
+
+.. productionlist::
+ integer: `decimalinteger` | `octinteger` | `hexinteger`
+ decimalinteger: `nonzerodigit` `digit`* | "0"+
+ octinteger: "0" ("o" | "O") `octdigit`+
+ hexinteger: "0" ("x" | "X") `hexdigit`+
+ bininteger: "0" ("b" | "B") `bindigit`+
+ nonzerodigit: "1"..."9"
+ octdigit: "0"..."7"
+ hexdigit: `digit` | "a"..."f" | "A"..."F"
+ bindigit: "0"..."1"
+
+Plain integer literals that are above the largest representable plain integer
+(e.g., 2147483647 when using 32-bit arithmetic) are accepted as if they were
+long integers instead. [#]_ There is no limit for long integer literals apart
+from what can be stored in available memory.
+
+Note that leading zeros in a non-zero decimal number are not allowed. This is
+for disambiguation with C-style octal literals, which Python used before version
+3.0.
+
+Some examples of integer literals::
+
+ 7 2147483647 0o177 0b100110111
+ 3 79228162514264337593543950336 0o377 0x100000000
+ 79228162514264337593543950336 0xdeadbeef
+
+
+.. _floating:
+
+Floating point literals
+-----------------------
+
+Floating point literals are described by the following lexical definitions:
+
+.. productionlist::
+ floatnumber: `pointfloat` | `exponentfloat`
+ pointfloat: [`intpart`] `fraction` | `intpart` "."
+ exponentfloat: (`intpart` | `pointfloat`) `exponent`
+ intpart: `digit`+
+ fraction: "." `digit`+
+ exponent: ("e" | "E") ["+" | "-"] `digit`+
+
+Note that the integer and exponent parts are always interpreted using radix 10.
+For example, ``077e010`` is legal, and denotes the same number as ``77e10``. The
+allowed range of floating point literals is implementation-dependent. Some
+examples of floating point literals::
+
+ 3.14 10. .001 1e100 3.14e-10 0e0
+
+Note that numeric literals do not include a sign; a phrase like ``-1`` is
+actually an expression composed of the unary operator ``-`` and the literal
+``1``.
+
+
+.. _imaginary:
+
+Imaginary literals
+------------------
+
+Imaginary literals are described by the following lexical definitions:
+
+.. productionlist::
+ imagnumber: (`floatnumber` | `intpart`) ("j" | "J")
+
+An imaginary literal yields a complex number with a real part of 0.0. Complex
+numbers are represented as a pair of floating point numbers and have the same
+restrictions on their range. To create a complex number with a nonzero real
+part, add a floating point number to it, e.g., ``(3+4j)``. Some examples of
+imaginary literals::
+
+ 3.14j 10.j 10j .001j 1e100j 3.14e-10j
+
+
+.. _operators:
+
+Operators
+=========
+
+.. index:: single: operators
+
+The following tokens are operators::
+
+ + - * ** / // %
+ << >> & | ^ ~
+ < > <= >= == !=
+
+
+.. _delimiters:
+
+Delimiters
+==========
+
+.. index:: single: delimiters
+
+The following tokens serve as delimiters in the grammar::
+
+ ( ) [ ] { } @
+ , : . ` = ;
+ += -= *= /= //= %=
+ &= |= ^= >>= <<= **=
+
+The period can also occur in floating-point and imaginary literals. A sequence
+of three periods has a special meaning as an ellipsis in slices. The second half
+of the list, the augmented assignment operators, serve lexically as delimiters,
+but also perform an operation.
+
+The following printing ASCII characters have special meaning as part of other
+tokens or are otherwise significant to the lexical analyzer::
+
+ ' " # \
+
+.. index:: single: ASCII@ASCII
+
+The following printing ASCII characters are not used in Python. Their
+occurrence outside string literals and comments is an unconditional error::
+
+ $ ?
+
+.. rubric:: Footnotes
+
+.. [#] In versions of Python prior to 2.4, octal and hexadecimal literals in the range
+ just above the largest representable plain integer but below the largest
+ unsigned 32-bit number (on a machine using 32-bit arithmetic), 4294967296, were
+ taken as the negative plain integer obtained by subtracting 4294967296 from
+ their unsigned value.
+
diff --git a/Doc/reference/simple_stmts.rst b/Doc/reference/simple_stmts.rst
new file mode 100644
index 0000000000..fbc626f7e3
--- /dev/null
+++ b/Doc/reference/simple_stmts.rst
@@ -0,0 +1,825 @@
+
+.. _simple:
+
+*****************
+Simple statements
+*****************
+
+.. index:: pair: simple; statement
+
+Simple statements are comprised within a single logical line. Several simple
+statements may occur on a single line separated by semicolons. The syntax for
+simple statements is:
+
+.. productionlist::
+ simple_stmt: `expression_stmt`
+ : | `assert_stmt`
+ : | `assignment_stmt`
+ : | `augmented_assignment_stmt`
+ : | `pass_stmt`
+ : | `del_stmt`
+ : | `return_stmt`
+ : | `yield_stmt`
+ : | `raise_stmt`
+ : | `break_stmt`
+ : | `continue_stmt`
+ : | `import_stmt`
+ : | `global_stmt`
+
+
+.. _exprstmts:
+
+Expression statements
+=====================
+
+.. index:: pair: expression; statement
+
+Expression statements are used (mostly interactively) to compute and write a
+value, or (usually) to call a procedure (a function that returns no meaningful
+result; in Python, procedures return the value ``None``). Other uses of
+expression statements are allowed and occasionally useful. The syntax for an
+expression statement is:
+
+.. productionlist::
+ expression_stmt: `expression_list`
+
+.. index:: pair: expression; list
+
+An expression statement evaluates the expression list (which may be a single
+expression).
+
+.. index::
+ builtin: repr
+ object: None
+ pair: string; conversion
+ single: output
+ pair: standard; output
+ pair: writing; values
+ pair: procedure; call
+
+In interactive mode, if the value is not ``None``, it is converted to a string
+using the built-in :func:`repr` function and the resulting string is written to
+standard output (see :func:`print`) on a line by itself. (Expression
+statements yielding ``None`` are not written, so that procedure calls do not
+cause any output.)
+
+
+.. _assert:
+
+Assert statements
+=================
+
+.. index::
+ statement: assert
+ pair: debugging; assertions
+
+Assert statements are a convenient way to insert debugging assertions into a
+program:
+
+.. productionlist::
+ assert_stmt: "assert" `expression` ["," `expression`]
+
+The simple form, ``assert expression``, is equivalent to ::
+
+ if __debug__:
+ if not expression: raise AssertionError
+
+The extended form, ``assert expression1, expression2``, is equivalent to ::
+
+ if __debug__:
+ if not expression1: raise AssertionError, expression2
+
+.. index::
+ single: __debug__
+ exception: AssertionError
+
+These equivalences assume that ``__debug__`` and :exc:`AssertionError` refer to
+the built-in variables with those names. In the current implementation, the
+built-in variable ``__debug__`` is ``True`` under normal circumstances,
+``False`` when optimization is requested (command line option -O). The current
+code generator emits no code for an assert statement when optimization is
+requested at compile time. Note that it is unnecessary to include the source
+code for the expression that failed in the error message; it will be displayed
+as part of the stack trace.
+
+Assignments to ``__debug__`` are illegal. The value for the built-in variable
+is determined when the interpreter starts.
+
+
+.. _assignment:
+
+Assignment statements
+=====================
+
+.. index::
+ pair: assignment; statement
+ pair: binding; name
+ pair: rebinding; name
+ object: mutable
+ pair: attribute; assignment
+
+Assignment statements are used to (re)bind names to values and to modify
+attributes or items of mutable objects:
+
+.. productionlist::
+ assignment_stmt: (`target_list` "=")+ (`expression_list` | `yield_expression`)
+ target_list: `target` ("," `target`)* [","]
+ target: `identifier`
+ : | "(" `target_list` ")"
+ : | "[" `target_list` "]"
+ : | `attributeref`
+ : | `subscription`
+ : | `slicing`
+
+(See section :ref:`primaries` for the syntax definitions for the last three
+symbols.)
+
+.. index:: pair: expression; list
+
+An assignment statement evaluates the expression list (remember that this can be
+a single expression or a comma-separated list, the latter yielding a tuple) and
+assigns the single resulting object to each of the target lists, from left to
+right.
+
+.. index::
+ single: target
+ pair: target; list
+
+Assignment is defined recursively depending on the form of the target (list).
+When a target is part of a mutable object (an attribute reference, subscription
+or slicing), the mutable object must ultimately perform the assignment and
+decide about its validity, and may raise an exception if the assignment is
+unacceptable. The rules observed by various types and the exceptions raised are
+given with the definition of the object types (see section :ref:`types`).
+
+.. index:: triple: target; list; assignment
+
+Assignment of an object to a target list is recursively defined as follows.
+
+* If the target list is a single target: The object is assigned to that target.
+
+* If the target list is a comma-separated list of targets: The object must be a
+ sequence with the same number of items as there are targets in the target list,
+ and the items are assigned, from left to right, to the corresponding targets.
+ (This rule is relaxed as of Python 1.5; in earlier versions, the object had to
+ be a tuple. Since strings are sequences, an assignment like ``a, b = "xy"`` is
+ now legal as long as the string has the right length.)
+
+Assignment of an object to a single target is recursively defined as follows.
+
+* If the target is an identifier (name):
+
+ .. index:: statement: global
+
+* If the name does not occur in a :keyword:`global` statement in the current
+ code block: the name is bound to the object in the current local namespace.
+
+* Otherwise: the name is bound to the object in the current global namespace.
+
+ .. index:: single: destructor
+
+ The name is rebound if it was already bound. This may cause the reference count
+ for the object previously bound to the name to reach zero, causing the object to
+ be deallocated and its destructor (if it has one) to be called.
+
+ .. % nested
+
+* If the target is a target list enclosed in parentheses or in square brackets:
+ The object must be a sequence with the same number of items as there are targets
+ in the target list, and its items are assigned, from left to right, to the
+ corresponding targets.
+
+ .. index:: pair: attribute; assignment
+
+* If the target is an attribute reference: The primary expression in the
+ reference is evaluated. It should yield an object with assignable attributes;
+ if this is not the case, :exc:`TypeError` is raised. That object is then asked
+ to assign the assigned object to the given attribute; if it cannot perform the
+ assignment, it raises an exception (usually but not necessarily
+ :exc:`AttributeError`).
+
+ .. index::
+ pair: subscription; assignment
+ object: mutable
+
+* If the target is a subscription: The primary expression in the reference is
+ evaluated. It should yield either a mutable sequence object (such as a list) or
+ a mapping object (such as a dictionary). Next, the subscript expression is
+ evaluated.
+
+ .. index::
+ object: sequence
+ object: list
+
+ If the primary is a mutable sequence object (such as a list), the subscript must
+ yield a plain integer. If it is negative, the sequence's length is added to it.
+ The resulting value must be a nonnegative integer less than the sequence's
+ length, and the sequence is asked to assign the assigned object to its item with
+ that index. If the index is out of range, :exc:`IndexError` is raised
+ (assignment to a subscripted sequence cannot add new items to a list).
+
+ .. index::
+ object: mapping
+ object: dictionary
+
+ If the primary is a mapping object (such as a dictionary), the subscript must
+ have a type compatible with the mapping's key type, and the mapping is then
+ asked to create a key/datum pair which maps the subscript to the assigned
+ object. This can either replace an existing key/value pair with the same key
+ value, or insert a new key/value pair (if no key with the same value existed).
+
+ .. index:: pair: slicing; assignment
+
+* If the target is a slicing: The primary expression in the reference is
+ evaluated. It should yield a mutable sequence object (such as a list). The
+ assigned object should be a sequence object of the same type. Next, the lower
+ and upper bound expressions are evaluated, insofar they are present; defaults
+ are zero and the sequence's length. The bounds should evaluate to (small)
+ integers. If either bound is negative, the sequence's length is added to it.
+ The resulting bounds are clipped to lie between zero and the sequence's length,
+ inclusive. Finally, the sequence object is asked to replace the slice with the
+ items of the assigned sequence. The length of the slice may be different from
+ the length of the assigned sequence, thus changing the length of the target
+ sequence, if the object allows it.
+
+(In the current implementation, the syntax for targets is taken to be the same
+as for expressions, and invalid syntax is rejected during the code generation
+phase, causing less detailed error messages.)
+
+WARNING: Although the definition of assignment implies that overlaps between the
+left-hand side and the right-hand side are 'safe' (for example ``a, b = b, a``
+swaps two variables), overlaps *within* the collection of assigned-to variables
+are not safe! For instance, the following program prints ``[0, 2]``::
+
+ x = [0, 1]
+ i = 0
+ i, x[i] = 1, 2
+ print x
+
+
+.. _augassign:
+
+Augmented assignment statements
+-------------------------------
+
+.. index::
+ pair: augmented; assignment
+ single: statement; assignment, augmented
+
+Augmented assignment is the combination, in a single statement, of a binary
+operation and an assignment statement:
+
+.. productionlist::
+ augmented_assignment_stmt: `target` `augop` (`expression_list` | `yield_expression`)
+ augop: "+=" | "-=" | "*=" | "/=" | "%=" | "**="
+ : | ">>=" | "<<=" | "&=" | "^=" | "|="
+
+(See section :ref:`primaries` for the syntax definitions for the last three
+symbols.)
+
+An augmented assignment evaluates the target (which, unlike normal assignment
+statements, cannot be an unpacking) and the expression list, performs the binary
+operation specific to the type of assignment on the two operands, and assigns
+the result to the original target. The target is only evaluated once.
+
+An augmented assignment expression like ``x += 1`` can be rewritten as ``x = x +
+1`` to achieve a similar, but not exactly equal effect. In the augmented
+version, ``x`` is only evaluated once. Also, when possible, the actual operation
+is performed *in-place*, meaning that rather than creating a new object and
+assigning that to the target, the old object is modified instead.
+
+With the exception of assigning to tuples and multiple targets in a single
+statement, the assignment done by augmented assignment statements is handled the
+same way as normal assignments. Similarly, with the exception of the possible
+*in-place* behavior, the binary operation performed by augmented assignment is
+the same as the normal binary operations.
+
+For targets which are attribute references, the initial value is retrieved with
+a :meth:`getattr` and the result is assigned with a :meth:`setattr`. Notice
+that the two methods do not necessarily refer to the same variable. When
+:meth:`getattr` refers to a class variable, :meth:`setattr` still writes to an
+instance variable. For example::
+
+ class A:
+ x = 3 # class variable
+ a = A()
+ a.x += 1 # writes a.x as 4 leaving A.x as 3
+
+
+.. _pass:
+
+The :keyword:`pass` statement
+=============================
+
+.. index:: statement: pass
+
+.. productionlist::
+ pass_stmt: "pass"
+
+.. index:: pair: null; operation
+
+:keyword:`pass` is a null operation --- when it is executed, nothing happens.
+It is useful as a placeholder when a statement is required syntactically, but no
+code needs to be executed, for example::
+
+ def f(arg): pass # a function that does nothing (yet)
+
+ class C: pass # a class with no methods (yet)
+
+
+.. _del:
+
+The :keyword:`del` statement
+============================
+
+.. index:: statement: del
+
+.. productionlist::
+ del_stmt: "del" `target_list`
+
+.. index::
+ pair: deletion; target
+ triple: deletion; target; list
+
+Deletion is recursively defined very similar to the way assignment is defined.
+Rather that spelling it out in full details, here are some hints.
+
+Deletion of a target list recursively deletes each target, from left to right.
+
+.. index::
+ statement: global
+ pair: unbinding; name
+
+Deletion of a name removes the binding of that name from the local or global
+namespace, depending on whether the name occurs in a :keyword:`global` statement
+in the same code block. If the name is unbound, a :exc:`NameError` exception
+will be raised.
+
+.. index:: pair: free; variable
+
+It is illegal to delete a name from the local namespace if it occurs as a free
+variable in a nested block.
+
+.. index:: pair: attribute; deletion
+
+Deletion of attribute references, subscriptions and slicings is passed to the
+primary object involved; deletion of a slicing is in general equivalent to
+assignment of an empty slice of the right type (but even this is determined by
+the sliced object).
+
+
+.. _return:
+
+The :keyword:`return` statement
+===============================
+
+.. index:: statement: return
+
+.. productionlist::
+ return_stmt: "return" [`expression_list`]
+
+.. index::
+ pair: function; definition
+ pair: class; definition
+
+:keyword:`return` may only occur syntactically nested in a function definition,
+not within a nested class definition.
+
+If an expression list is present, it is evaluated, else ``None`` is substituted.
+
+:keyword:`return` leaves the current function call with the expression list (or
+``None``) as return value.
+
+.. index:: keyword: finally
+
+When :keyword:`return` passes control out of a :keyword:`try` statement with a
+:keyword:`finally` clause, that :keyword:`finally` clause is executed before
+really leaving the function.
+
+In a generator function, the :keyword:`return` statement is not allowed to
+include an :token:`expression_list`. In that context, a bare :keyword:`return`
+indicates that the generator is done and will cause :exc:`StopIteration` to be
+raised.
+
+
+.. _yield:
+
+The :keyword:`yield` statement
+==============================
+
+.. index:: statement: yield
+
+.. productionlist::
+ yield_stmt: `yield_expression`
+
+.. index::
+ single: generator; function
+ single: generator; iterator
+ single: function; generator
+ exception: StopIteration
+
+The :keyword:`yield` statement is only used when defining a generator function,
+and is only used in the body of the generator function. Using a :keyword:`yield`
+statement in a function definition is sufficient to cause that definition to
+create a generator function instead of a normal function.
+
+When a generator function is called, it returns an iterator known as a generator
+iterator, or more commonly, a generator. The body of the generator function is
+executed by calling the generator's :meth:`__next__` method repeatedly until it
+raises an exception.
+
+When a :keyword:`yield` statement is executed, the state of the generator is
+frozen and the value of :token:`expression_list` is returned to
+:meth:`__next__`'s caller. By "frozen" we mean that all local state is
+retained, including the current bindings of local variables, the instruction
+pointer, and the internal evaluation stack: enough information is saved so that
+the next time :meth:`__next__` is invoked, the function can proceed exactly as
+if the :keyword:`yield` statement were just another external call.
+
+As of Python version 2.5, the :keyword:`yield` statement is now allowed in the
+:keyword:`try` clause of a :keyword:`try` ... :keyword:`finally` construct. If
+the generator is not resumed before it is finalized (by reaching a zero
+reference count or by being garbage collected), the generator-iterator's
+:meth:`close` method will be called, allowing any pending :keyword:`finally`
+clauses to execute.
+
+.. note::
+
+ In Python 2.2, the :keyword:`yield` statement is only allowed when the
+ ``generators`` feature has been enabled. It will always be enabled in Python
+ 2.3. This ``__future__`` import statement can be used to enable the feature::
+
+ from __future__ import generators
+
+
+.. seealso::
+
+ :pep:`0255` - Simple Generators
+ The proposal for adding generators and the :keyword:`yield` statement to Python.
+
+ :pep:`0342` - Coroutines via Enhanced Generators
+ The proposal that, among other generator enhancements, proposed allowing
+ :keyword:`yield` to appear inside a :keyword:`try` ... :keyword:`finally` block.
+
+
+.. _raise:
+
+The :keyword:`raise` statement
+==============================
+
+.. index:: statement: raise
+
+.. productionlist::
+ raise_stmt: "raise" [`expression` ["," `expression` ["," `expression`]]]
+
+.. index::
+ single: exception
+ pair: raising; exception
+
+If no expressions are present, :keyword:`raise` re-raises the last exception
+that was active in the current scope. If no exception is active in the current
+scope, a :exc:`TypeError` exception is raised indicating that this is an error
+(if running under IDLE, a :exc:`Queue.Empty` exception is raised instead).
+
+Otherwise, :keyword:`raise` evaluates the expressions to get three objects,
+using ``None`` as the value of omitted expressions. The first two objects are
+used to determine the *type* and *value* of the exception.
+
+If the first object is an instance, the type of the exception is the class of
+the instance, the instance itself is the value, and the second object must be
+``None``.
+
+If the first object is a class, it becomes the type of the exception. The second
+object is used to determine the exception value: If it is an instance of the
+class, the instance becomes the exception value. If the second object is a
+tuple, it is used as the argument list for the class constructor; if it is
+``None``, an empty argument list is used, and any other object is treated as a
+single argument to the constructor. The instance so created by calling the
+constructor is used as the exception value.
+
+.. index:: object: traceback
+
+If a third object is present and not ``None``, it must be a traceback object
+(see section :ref:`types`), and it is substituted instead of the current
+location as the place where the exception occurred. If the third object is
+present and not a traceback object or ``None``, a :exc:`TypeError` exception is
+raised. The three-expression form of :keyword:`raise` is useful to re-raise an
+exception transparently in an except clause, but :keyword:`raise` with no
+expressions should be preferred if the exception to be re-raised was the most
+recently active exception in the current scope.
+
+Additional information on exceptions can be found in section :ref:`exceptions`,
+and information about handling exceptions is in section :ref:`try`.
+
+
+.. _break:
+
+The :keyword:`break` statement
+==============================
+
+.. index:: statement: break
+
+.. productionlist::
+ break_stmt: "break"
+
+.. index::
+ statement: for
+ statement: while
+ pair: loop; statement
+
+:keyword:`break` may only occur syntactically nested in a :keyword:`for` or
+:keyword:`while` loop, but not nested in a function or class definition within
+that loop.
+
+.. index:: keyword: else
+
+It terminates the nearest enclosing loop, skipping the optional :keyword:`else`
+clause if the loop has one.
+
+.. index:: pair: loop control; target
+
+If a :keyword:`for` loop is terminated by :keyword:`break`, the loop control
+target keeps its current value.
+
+.. index:: keyword: finally
+
+When :keyword:`break` passes control out of a :keyword:`try` statement with a
+:keyword:`finally` clause, that :keyword:`finally` clause is executed before
+really leaving the loop.
+
+
+.. _continue:
+
+The :keyword:`continue` statement
+=================================
+
+.. index:: statement: continue
+
+.. productionlist::
+ continue_stmt: "continue"
+
+.. index::
+ statement: for
+ statement: while
+ pair: loop; statement
+ keyword: finally
+
+:keyword:`continue` may only occur syntactically nested in a :keyword:`for` or
+:keyword:`while` loop, but not nested in a function or class definition or
+:keyword:`finally` statement within that loop. [#]_ It continues with the next
+cycle of the nearest enclosing loop.
+
+
+.. _import:
+
+The :keyword:`import` statement
+===============================
+
+.. index::
+ statement: import
+ single: module; importing
+ pair: name; binding
+ keyword: from
+
+.. productionlist::
+ import_stmt: "import" `module` ["as" `name`] ( "," `module` ["as" `name`] )*
+ : | "from" `relative_module` "import" `identifier` ["as" `name`]
+ : ( "," `identifier` ["as" `name`] )*
+ : | "from" `relative_module` "import" "(" `identifier` ["as" `name`]
+ : ( "," `identifier` ["as" `name`] )* [","] ")"
+ : | "from" `module` "import" "*"
+ module: (`identifier` ".")* `identifier`
+ relative_module: "."* `module` | "."+
+ name: `identifier`
+
+Import statements are executed in two steps: (1) find a module, and initialize
+it if necessary; (2) define a name or names in the local namespace (of the scope
+where the :keyword:`import` statement occurs). The first form (without
+:keyword:`from`) repeats these steps for each identifier in the list. The form
+with :keyword:`from` performs step (1) once, and then performs step (2)
+repeatedly.
+
+In this context, to "initialize" a built-in or extension module means to call an
+initialization function that the module must provide for the purpose (in the
+reference implementation, the function's name is obtained by prepending string
+"init" to the module's name); to "initialize" a Python-coded module means to
+execute the module's body.
+
+.. index::
+ single: modules (in module sys)
+ single: sys.modules
+ pair: module; name
+ pair: built-in; module
+ pair: user-defined; module
+ module: sys
+ pair: filename; extension
+ triple: module; search; path
+
+The system maintains a table of modules that have been or are being initialized,
+indexed by module name. This table is accessible as ``sys.modules``. When a
+module name is found in this table, step (1) is finished. If not, a search for
+a module definition is started. When a module is found, it is loaded. Details
+of the module searching and loading process are implementation and platform
+specific. It generally involves searching for a "built-in" module with the
+given name and then searching a list of locations given as ``sys.path``.
+
+.. index::
+ pair: module; initialization
+ exception: ImportError
+ single: code block
+ exception: SyntaxError
+
+If a built-in module is found, its built-in initialization code is executed and
+step (1) is finished. If no matching file is found, :exc:`ImportError` is
+raised. If a file is found, it is parsed, yielding an executable code block. If
+a syntax error occurs, :exc:`SyntaxError` is raised. Otherwise, an empty module
+of the given name is created and inserted in the module table, and then the code
+block is executed in the context of this module. Exceptions during this
+execution terminate step (1).
+
+When step (1) finishes without raising an exception, step (2) can begin.
+
+The first form of :keyword:`import` statement binds the module name in the local
+namespace to the module object, and then goes on to import the next identifier,
+if any. If the module name is followed by :keyword:`as`, the name following
+:keyword:`as` is used as the local name for the module.
+
+.. index::
+ pair: name; binding
+ exception: ImportError
+
+The :keyword:`from` form does not bind the module name: it goes through the list
+of identifiers, looks each one of them up in the module found in step (1), and
+binds the name in the local namespace to the object thus found. As with the
+first form of :keyword:`import`, an alternate local name can be supplied by
+specifying ":keyword:`as` localname". If a name is not found,
+:exc:`ImportError` is raised. If the list of identifiers is replaced by a star
+(``'*'``), all public names defined in the module are bound in the local
+namespace of the :keyword:`import` statement..
+
+.. index:: single: __all__ (optional module attribute)
+
+The *public names* defined by a module are determined by checking the module's
+namespace for a variable named ``__all__``; if defined, it must be a sequence of
+strings which are names defined or imported by that module. The names given in
+``__all__`` are all considered public and are required to exist. If ``__all__``
+is not defined, the set of public names includes all names found in the module's
+namespace which do not begin with an underscore character (``'_'``).
+``__all__`` should contain the entire public API. It is intended to avoid
+accidentally exporting items that are not part of the API (such as library
+modules which were imported and used within the module).
+
+The :keyword:`from` form with ``*`` may only occur in a module scope. If the
+wild card form of import --- ``import *`` --- is used in a function and the
+function contains or is a nested block with free variables, the compiler will
+raise a :exc:`SyntaxError`.
+
+.. index::
+ keyword: from
+ statement: from
+
+.. index::
+ triple: hierarchical; module; names
+ single: packages
+ single: __init__.py
+
+**Hierarchical module names:** when the module names contains one or more dots,
+the module search path is carried out differently. The sequence of identifiers
+up to the last dot is used to find a "package"; the final identifier is then
+searched inside the package. A package is generally a subdirectory of a
+directory on ``sys.path`` that has a file :file:`__init__.py`. [XXX Can't be
+bothered to spell this out right now; see the URL
+http://www.python.org/doc/essays/packages.html for more details, also about how
+the module search works from inside a package.]
+
+.. %
+
+.. index:: builtin: __import__
+
+The built-in function :func:`__import__` is provided to support applications
+that determine which modules need to be loaded dynamically; refer to
+:ref:`built-in-funcs` for additional information.
+
+
+.. _future:
+
+Future statements
+-----------------
+
+.. index:: pair: future; statement
+
+A :dfn:`future statement` is a directive to the compiler that a particular
+module should be compiled using syntax or semantics that will be available in a
+specified future release of Python. The future statement is intended to ease
+migration to future versions of Python that introduce incompatible changes to
+the language. It allows use of the new features on a per-module basis before
+the release in which the feature becomes standard.
+
+.. productionlist:: *
+ future_statement: "from" "__future__" "import" feature ["as" name]
+ : ("," feature ["as" name])*
+ : | "from" "__future__" "import" "(" feature ["as" name]
+ : ("," feature ["as" name])* [","] ")"
+ feature: identifier
+ name: identifier
+
+A future statement must appear near the top of the module. The only lines that
+can appear before a future statement are:
+
+* the module docstring (if any),
+* comments,
+* blank lines, and
+* other future statements.
+
+The features recognized by Python 2.5 are ``absolute_import``, ``division``,
+``generators``, ``nested_scopes`` and ``with_statement``. ``generators`` and
+``nested_scopes`` are redundant in Python version 2.3 and above because they
+are always enabled.
+
+A future statement is recognized and treated specially at compile time: Changes
+to the semantics of core constructs are often implemented by generating
+different code. It may even be the case that a new feature introduces new
+incompatible syntax (such as a new reserved word), in which case the compiler
+may need to parse the module differently. Such decisions cannot be pushed off
+until runtime.
+
+For any given release, the compiler knows which feature names have been defined,
+and raises a compile-time error if a future statement contains a feature not
+known to it.
+
+The direct runtime semantics are the same as for any import statement: there is
+a standard module :mod:`__future__`, described later, and it will be imported in
+the usual way at the time the future statement is executed.
+
+The interesting runtime semantics depend on the specific feature enabled by the
+future statement.
+
+Note that there is nothing special about the statement::
+
+ import __future__ [as name]
+
+That is not a future statement; it's an ordinary import statement with no
+special semantics or syntax restrictions.
+
+Code compiled by calls to the builtin functions :func:`exec` and :func:`compile`
+that occur in a module :mod:`M` containing a future
+statement will, by default, use the new syntax or semantics associated with the
+future statement. This can, starting with Python 2.2 be controlled by optional
+arguments to :func:`compile` --- see the documentation of that function
+for details.
+
+A future statement typed at an interactive interpreter prompt will take effect
+for the rest of the interpreter session. If an interpreter is started with the
+:option:`-i` option, is passed a script name to execute, and the script includes
+a future statement, it will be in effect in the interactive session started
+after the script is executed.
+
+
+.. _global:
+
+The :keyword:`global` statement
+===============================
+
+.. index:: statement: global
+
+.. productionlist::
+ global_stmt: "global" `identifier` ("," `identifier`)*
+
+.. index:: triple: global; name; binding
+
+The :keyword:`global` statement is a declaration which holds for the entire
+current code block. It means that the listed identifiers are to be interpreted
+as globals. It would be impossible to assign to a global variable without
+:keyword:`global`, although free variables may refer to globals without being
+declared global.
+
+Names listed in a :keyword:`global` statement must not be used in the same code
+block textually preceding that :keyword:`global` statement.
+
+Names listed in a :keyword:`global` statement must not be defined as formal
+parameters or in a :keyword:`for` loop control target, :keyword:`class`
+definition, function definition, or :keyword:`import` statement.
+
+(The current implementation does not enforce the latter two restrictions, but
+programs should not abuse this freedom, as future implementations may enforce
+them or silently change the meaning of the program.)
+
+.. index::
+ builtin: exec
+ builtin: eval
+ builtin: compile
+
+**Programmer's note:** the :keyword:`global` is a directive to the parser. It
+applies only to code parsed at the same time as the :keyword:`global` statement.
+In particular, a :keyword:`global` statement contained in a string or code
+object supplied to the builtin :func:`exec` function does not affect the code
+block *containing* the function call, and code contained in such a string is
+unaffected by :keyword:`global` statements in the code containing the function
+call. The same applies to the :func:`eval` and :func:`compile` functions.
+
+.. rubric:: Footnotes
+
+.. [#] It may occur within an :keyword:`except` or :keyword:`else` clause. The
+ restriction on occurring in the :keyword:`try` clause is implementor's laziness
+ and will eventually be lifted.
+
diff --git a/Doc/reference/toplevel_components.rst b/Doc/reference/toplevel_components.rst
new file mode 100644
index 0000000000..2149311783
--- /dev/null
+++ b/Doc/reference/toplevel_components.rst
@@ -0,0 +1,123 @@
+
+.. _top-level:
+
+********************
+Top-level components
+********************
+
+.. index:: single: interpreter
+
+The Python interpreter can get its input from a number of sources: from a script
+passed to it as standard input or as program argument, typed in interactively,
+from a module source file, etc. This chapter gives the syntax used in these
+cases.
+
+
+.. _programs:
+
+Complete Python programs
+========================
+
+.. index:: single: program
+
+.. index::
+ module: sys
+ module: __main__
+ module: __builtin__
+
+While a language specification need not prescribe how the language interpreter
+is invoked, it is useful to have a notion of a complete Python program. A
+complete Python program is executed in a minimally initialized environment: all
+built-in and standard modules are available, but none have been initialized,
+except for :mod:`sys` (various system services), :mod:`__builtin__` (built-in
+functions, exceptions and ``None``) and :mod:`__main__`. The latter is used to
+provide the local and global namespace for execution of the complete program.
+
+The syntax for a complete Python program is that for file input, described in
+the next section.
+
+.. index::
+ single: interactive mode
+ module: __main__
+
+The interpreter may also be invoked in interactive mode; in this case, it does
+not read and execute a complete program but reads and executes one statement
+(possibly compound) at a time. The initial environment is identical to that of
+a complete program; each statement is executed in the namespace of
+:mod:`__main__`.
+
+.. index::
+ single: UNIX
+ single: command line
+ single: standard input
+
+Under Unix, a complete program can be passed to the interpreter in three forms:
+with the :option:`-c` *string* command line option, as a file passed as the
+first command line argument, or as standard input. If the file or standard input
+is a tty device, the interpreter enters interactive mode; otherwise, it executes
+the file as a complete program.
+
+
+.. _file-input:
+
+File input
+==========
+
+All input read from non-interactive files has the same form:
+
+.. productionlist::
+ file_input: (NEWLINE | `statement`)*
+
+This syntax is used in the following situations:
+
+* when parsing a complete Python program (from a file or from a string);
+
+* when parsing a module;
+
+* when parsing a string passed to the :func:`exec` function;
+
+
+.. _interactive:
+
+Interactive input
+=================
+
+Input in interactive mode is parsed using the following grammar:
+
+.. productionlist::
+ interactive_input: [`stmt_list`] NEWLINE | `compound_stmt` NEWLINE
+
+Note that a (top-level) compound statement must be followed by a blank line in
+interactive mode; this is needed to help the parser detect the end of the input.
+
+
+.. _expression-input:
+
+Expression input
+================
+
+.. index:: single: input
+
+.. index:: builtin: eval
+
+There are two forms of expression input. Both ignore leading whitespace. The
+string argument to :func:`eval` must have the following form:
+
+.. productionlist::
+ eval_input: `expression_list` NEWLINE*
+
+.. index:: builtin: input
+
+The input line read by :func:`input` must have the following form:
+
+.. productionlist::
+ input_input: `expression_list` NEWLINE
+
+.. index::
+ object: file
+ single: input; raw
+ single: readline() (file method)
+
+Note: to read 'raw' input line without interpretation, you can use the the
+:meth:`readline` method of file objects, including ``sys.stdin``.
+
diff --git a/Doc/tools/sphinx-build.py b/Doc/tools/sphinx-build.py
new file mode 100644
index 0000000000..20516b642b
--- /dev/null
+++ b/Doc/tools/sphinx-build.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+"""
+ Sphinx - Python documentation toolchain
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+ :copyright: 2007 by Georg Brandl.
+ :license: Python license.
+"""
+
+import sys
+
+if __name__ == '__main__':
+ from sphinx import main
+ sys.exit(main(sys.argv))
diff --git a/Doc/tools/sphinx-web.py b/Doc/tools/sphinx-web.py
new file mode 100644
index 0000000000..5f7b50b6fd
--- /dev/null
+++ b/Doc/tools/sphinx-web.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+"""
+ Sphinx - Python documentation webserver
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+ :copyright: 2007 by Georg Brandl.
+ :license: Python license.
+"""
+
+import sys
+
+if __name__ == '__main__':
+ from sphinx.web import main
+ sys.exit(main(sys.argv))
diff --git a/Doc/tutorial/appetite.rst b/Doc/tutorial/appetite.rst
new file mode 100644
index 0000000000..f1c80e9598
--- /dev/null
+++ b/Doc/tutorial/appetite.rst
@@ -0,0 +1,89 @@
+.. _tut-intro:
+
+**********************
+Whetting Your Appetite
+**********************
+
+If you do much work on computers, eventually you find that there's some task
+you'd like to automate. For example, you may wish to perform a
+search-and-replace over a large number of text files, or rename and rearrange a
+bunch of photo files in a complicated way. Perhaps you'd like to write a small
+custom database, or a specialized GUI application, or a simple game.
+
+If you're a professional software developer, you may have to work with several
+C/C++/Java libraries but find the usual write/compile/test/re-compile cycle is
+too slow. Perhaps you're writing a test suite for such a library and find
+writing the testing code a tedious task. Or maybe you've written a program that
+could use an extension language, and you don't want to design and implement a
+whole new language for your application.
+
+Python is just the language for you.
+
+You could write a Unix shell script or Windows batch files for some of these
+tasks, but shell scripts are best at moving around files and changing text data,
+not well-suited for GUI applications or games. You could write a C/C++/Java
+program, but it can take a lot of development time to get even a first-draft
+program. Python is simpler to use, available on Windows, MacOS X, and Unix
+operating systems, and will help you get the job done more quickly.
+
+Python is simple to use, but it is a real programming language, offering much
+more structure and support for large programs than shell scripts or batch files
+can offer. On the other hand, Python also offers much more error checking than
+C, and, being a *very-high-level language*, it has high-level data types built
+in, such as flexible arrays and dictionaries. Because of its more general data
+types Python is applicable to a much larger problem domain than Awk or even
+Perl, yet many things are at least as easy in Python as in those languages.
+
+Python allows you to split your program into modules that can be reused in other
+Python programs. It comes with a large collection of standard modules that you
+can use as the basis of your programs --- or as examples to start learning to
+program in Python. Some of these modules provide things like file I/O, system
+calls, sockets, and even interfaces to graphical user interface toolkits like
+Tk.
+
+Python is an interpreted language, which can save you considerable time during
+program development because no compilation and linking is necessary. The
+interpreter can be used interactively, which makes it easy to experiment with
+features of the language, to write throw-away programs, or to test functions
+during bottom-up program development. It is also a handy desk calculator.
+
+Python enables programs to be written compactly and readably. Programs written
+in Python are typically much shorter than equivalent C, C++, or Java programs,
+for several reasons:
+
+* the high-level data types allow you to express complex operations in a single
+ statement;
+
+* statement grouping is done by indentation instead of beginning and ending
+ brackets;
+
+* no variable or argument declarations are necessary.
+
+Python is *extensible*: if you know how to program in C it is easy to add a new
+built-in function or module to the interpreter, either to perform critical
+operations at maximum speed, or to link Python programs to libraries that may
+only be available in binary form (such as a vendor-specific graphics library).
+Once you are really hooked, you can link the Python interpreter into an
+application written in C and use it as an extension or command language for that
+application.
+
+By the way, the language is named after the BBC show "Monty Python's Flying
+Circus" and has nothing to do with nasty reptiles. Making references to Monty
+Python skits in documentation is not only allowed, it is encouraged!
+
+Now that you are all excited about Python, you'll want to examine it in some
+more detail. Since the best way to learn a language is to use it, the tutorial
+invites you to play with the Python interpreter as you read.
+
+.. % \section{Where From Here \label{where}}
+
+In the next chapter, the mechanics of using the interpreter are explained. This
+is rather mundane information, but essential for trying out the examples shown
+later.
+
+The rest of the tutorial introduces various features of the Python language and
+system through examples, beginning with simple expressions, statements and data
+types, through functions and modules, and finally touching upon advanced
+concepts like exceptions and user-defined classes.
+
+
diff --git a/Doc/tutorial/classes.rst b/Doc/tutorial/classes.rst
new file mode 100644
index 0000000000..b733e1eef0
--- /dev/null
+++ b/Doc/tutorial/classes.rst
@@ -0,0 +1,792 @@
+.. _tut-classes:
+
+*******
+Classes
+*******
+
+Python's class mechanism adds classes to the language with a minimum of new
+syntax and semantics. It is a mixture of the class mechanisms found in C++ and
+Modula-3. As is true for modules, classes in Python do not put an absolute
+barrier between definition and user, but rather rely on the politeness of the
+user not to "break into the definition." The most important features of classes
+are retained with full power, however: the class inheritance mechanism allows
+multiple base classes, a derived class can override any methods of its base
+class or classes, and a method can call the method of a base class with the same
+name. Objects can contain an arbitrary amount of private data.
+
+In C++ terminology, all class members (including the data members) are *public*,
+and all member functions are *virtual*. There are no special constructors or
+destructors. As in Modula-3, there are no shorthands for referencing the
+object's members from its methods: the method function is declared with an
+explicit first argument representing the object, which is provided implicitly by
+the call. As in Smalltalk, classes themselves are objects, albeit in the wider
+sense of the word: in Python, all data types are objects. This provides
+semantics for importing and renaming. Unlike C++ and Modula-3, built-in types
+can be used as base classes for extension by the user. Also, like in C++ but
+unlike in Modula-3, most built-in operators with special syntax (arithmetic
+operators, subscripting etc.) can be redefined for class instances.
+
+
+.. _tut-terminology:
+
+A Word About Terminology
+========================
+
+Lacking universally accepted terminology to talk about classes, I will make
+occasional use of Smalltalk and C++ terms. (I would use Modula-3 terms, since
+its object-oriented semantics are closer to those of Python than C++, but I
+expect that few readers have heard of it.)
+
+Objects have individuality, and multiple names (in multiple scopes) can be bound
+to the same object. This is known as aliasing in other languages. This is
+usually not appreciated on a first glance at Python, and can be safely ignored
+when dealing with immutable basic types (numbers, strings, tuples). However,
+aliasing has an (intended!) effect on the semantics of Python code involving
+mutable objects such as lists, dictionaries, and most types representing
+entities outside the program (files, windows, etc.). This is usually used to
+the benefit of the program, since aliases behave like pointers in some respects.
+For example, passing an object is cheap since only a pointer is passed by the
+implementation; and if a function modifies an object passed as an argument, the
+caller will see the change --- this eliminates the need for two different
+argument passing mechanisms as in Pascal.
+
+
+.. _tut-scopes:
+
+Python Scopes and Name Spaces
+=============================
+
+Before introducing classes, I first have to tell you something about Python's
+scope rules. Class definitions play some neat tricks with namespaces, and you
+need to know how scopes and namespaces work to fully understand what's going on.
+Incidentally, knowledge about this subject is useful for any advanced Python
+programmer.
+
+Let's begin with some definitions.
+
+A *namespace* is a mapping from names to objects. Most namespaces are currently
+implemented as Python dictionaries, but that's normally not noticeable in any
+way (except for performance), and it may change in the future. Examples of
+namespaces are: the set of built-in names (functions such as :func:`abs`, and
+built-in exception names); the global names in a module; and the local names in
+a function invocation. In a sense the set of attributes of an object also form
+a namespace. The important thing to know about namespaces is that there is
+absolutely no relation between names in different namespaces; for instance, two
+different modules may both define a function "maximize" without confusion ---
+users of the modules must prefix it with the module name.
+
+By the way, I use the word *attribute* for any name following a dot --- for
+example, in the expression ``z.real``, ``real`` is an attribute of the object
+``z``. Strictly speaking, references to names in modules are attribute
+references: in the expression ``modname.funcname``, ``modname`` is a module
+object and ``funcname`` is an attribute of it. In this case there happens to be
+a straightforward mapping between the module's attributes and the global names
+defined in the module: they share the same namespace! [#]_
+
+Attributes may be read-only or writable. In the latter case, assignment to
+attributes is possible. Module attributes are writable: you can write
+``modname.the_answer = 42``. Writable attributes may also be deleted with the
+:keyword:`del` statement. For example, ``del modname.the_answer`` will remove
+the attribute :attr:`the_answer` from the object named by ``modname``.
+
+Name spaces are created at different moments and have different lifetimes. The
+namespace containing the built-in names is created when the Python interpreter
+starts up, and is never deleted. The global namespace for a module is created
+when the module definition is read in; normally, module namespaces also last
+until the interpreter quits. The statements executed by the top-level
+invocation of the interpreter, either read from a script file or interactively,
+are considered part of a module called :mod:`__main__`, so they have their own
+global namespace. (The built-in names actually also live in a module; this is
+called :mod:`__builtin__`.)
+
+The local namespace for a function is created when the function is called, and
+deleted when the function returns or raises an exception that is not handled
+within the function. (Actually, forgetting would be a better way to describe
+what actually happens.) Of course, recursive invocations each have their own
+local namespace.
+
+A *scope* is a textual region of a Python program where a namespace is directly
+accessible. "Directly accessible" here means that an unqualified reference to a
+name attempts to find the name in the namespace.
+
+Although scopes are determined statically, they are used dynamically. At any
+time during execution, there are at least three nested scopes whose namespaces
+are directly accessible: the innermost scope, which is searched first, contains
+the local names; the namespaces of any enclosing functions, which are searched
+starting with the nearest enclosing scope; the middle scope, searched next,
+contains the current module's global names; and the outermost scope (searched
+last) is the namespace containing built-in names.
+
+If a name is declared global, then all references and assignments go directly to
+the middle scope containing the module's global names. Otherwise, all variables
+found outside of the innermost scope are read-only (an attempt to write to such
+a variable will simply create a *new* local variable in the innermost scope,
+leaving the identically named outer variable unchanged).
+
+Usually, the local scope references the local names of the (textually) current
+function. Outside functions, the local scope references the same namespace as
+the global scope: the module's namespace. Class definitions place yet another
+namespace in the local scope.
+
+It is important to realize that scopes are determined textually: the global
+scope of a function defined in a module is that module's namespace, no matter
+from where or by what alias the function is called. On the other hand, the
+actual search for names is done dynamically, at run time --- however, the
+language definition is evolving towards static name resolution, at "compile"
+time, so don't rely on dynamic name resolution! (In fact, local variables are
+already determined statically.)
+
+A special quirk of Python is that assignments always go into the innermost
+scope. Assignments do not copy data --- they just bind names to objects. The
+same is true for deletions: the statement ``del x`` removes the binding of ``x``
+from the namespace referenced by the local scope. In fact, all operations that
+introduce new names use the local scope: in particular, import statements and
+function definitions bind the module or function name in the local scope. (The
+:keyword:`global` statement can be used to indicate that particular variables
+live in the global scope.)
+
+
+.. _tut-firstclasses:
+
+A First Look at Classes
+=======================
+
+Classes introduce a little bit of new syntax, three new object types, and some
+new semantics.
+
+
+.. _tut-classdefinition:
+
+Class Definition Syntax
+-----------------------
+
+The simplest form of class definition looks like this::
+
+ class ClassName:
+ <statement-1>
+ .
+ .
+ .
+ <statement-N>
+
+Class definitions, like function definitions (:keyword:`def` statements) must be
+executed before they have any effect. (You could conceivably place a class
+definition in a branch of an :keyword:`if` statement, or inside a function.)
+
+In practice, the statements inside a class definition will usually be function
+definitions, but other statements are allowed, and sometimes useful --- we'll
+come back to this later. The function definitions inside a class normally have
+a peculiar form of argument list, dictated by the calling conventions for
+methods --- again, this is explained later.
+
+When a class definition is entered, a new namespace is created, and used as the
+local scope --- thus, all assignments to local variables go into this new
+namespace. In particular, function definitions bind the name of the new
+function here.
+
+When a class definition is left normally (via the end), a *class object* is
+created. This is basically a wrapper around the contents of the namespace
+created by the class definition; we'll learn more about class objects in the
+next section. The original local scope (the one in effect just before the class
+definition was entered) is reinstated, and the class object is bound here to the
+class name given in the class definition header (:class:`ClassName` in the
+example).
+
+
+.. _tut-classobjects:
+
+Class Objects
+-------------
+
+Class objects support two kinds of operations: attribute references and
+instantiation.
+
+*Attribute references* use the standard syntax used for all attribute references
+in Python: ``obj.name``. Valid attribute names are all the names that were in
+the class's namespace when the class object was created. So, if the class
+definition looked like this::
+
+ class MyClass:
+ "A simple example class"
+ i = 12345
+ def f(self):
+ return 'hello world'
+
+then ``MyClass.i`` and ``MyClass.f`` are valid attribute references, returning
+an integer and a function object, respectively. Class attributes can also be
+assigned to, so you can change the value of ``MyClass.i`` by assignment.
+:attr:`__doc__` is also a valid attribute, returning the docstring belonging to
+the class: ``"A simple example class"``.
+
+Class *instantiation* uses function notation. Just pretend that the class
+object is a parameterless function that returns a new instance of the class.
+For example (assuming the above class)::
+
+ x = MyClass()
+
+creates a new *instance* of the class and assigns this object to the local
+variable ``x``.
+
+The instantiation operation ("calling" a class object) creates an empty object.
+Many classes like to create objects with instances customized to a specific
+initial state. Therefore a class may define a special method named
+:meth:`__init__`, like this::
+
+ def __init__(self):
+ self.data = []
+
+When a class defines an :meth:`__init__` method, class instantiation
+automatically invokes :meth:`__init__` for the newly-created class instance. So
+in this example, a new, initialized instance can be obtained by::
+
+ x = MyClass()
+
+Of course, the :meth:`__init__` method may have arguments for greater
+flexibility. In that case, arguments given to the class instantiation operator
+are passed on to :meth:`__init__`. For example, ::
+
+ >>> class Complex:
+ ... def __init__(self, realpart, imagpart):
+ ... self.r = realpart
+ ... self.i = imagpart
+ ...
+ >>> x = Complex(3.0, -4.5)
+ >>> x.r, x.i
+ (3.0, -4.5)
+
+
+.. _tut-instanceobjects:
+
+Instance Objects
+----------------
+
+Now what can we do with instance objects? The only operations understood by
+instance objects are attribute references. There are two kinds of valid
+attribute names, data attributes and methods.
+
+*data attributes* correspond to "instance variables" in Smalltalk, and to "data
+members" in C++. Data attributes need not be declared; like local variables,
+they spring into existence when they are first assigned to. For example, if
+``x`` is the instance of :class:`MyClass` created above, the following piece of
+code will print the value ``16``, without leaving a trace::
+
+ x.counter = 1
+ while x.counter < 10:
+ x.counter = x.counter * 2
+ print x.counter
+ del x.counter
+
+The other kind of instance attribute reference is a *method*. A method is a
+function that "belongs to" an object. (In Python, the term method is not unique
+to class instances: other object types can have methods as well. For example,
+list objects have methods called append, insert, remove, sort, and so on.
+However, in the following discussion, we'll use the term method exclusively to
+mean methods of class instance objects, unless explicitly stated otherwise.)
+
+.. index:: object: method
+
+Valid method names of an instance object depend on its class. By definition,
+all attributes of a class that are function objects define corresponding
+methods of its instances. So in our example, ``x.f`` is a valid method
+reference, since ``MyClass.f`` is a function, but ``x.i`` is not, since
+``MyClass.i`` is not. But ``x.f`` is not the same thing as ``MyClass.f`` --- it
+is a *method object*, not a function object.
+
+
+.. _tut-methodobjects:
+
+Method Objects
+--------------
+
+Usually, a method is called right after it is bound::
+
+ x.f()
+
+In the :class:`MyClass` example, this will return the string ``'hello world'``.
+However, it is not necessary to call a method right away: ``x.f`` is a method
+object, and can be stored away and called at a later time. For example::
+
+ xf = x.f
+ while True:
+ print xf()
+
+will continue to print ``hello world`` until the end of time.
+
+What exactly happens when a method is called? You may have noticed that
+``x.f()`` was called without an argument above, even though the function
+definition for :meth:`f` specified an argument. What happened to the argument?
+Surely Python raises an exception when a function that requires an argument is
+called without any --- even if the argument isn't actually used...
+
+Actually, you may have guessed the answer: the special thing about methods is
+that the object is passed as the first argument of the function. In our
+example, the call ``x.f()`` is exactly equivalent to ``MyClass.f(x)``. In
+general, calling a method with a list of *n* arguments is equivalent to calling
+the corresponding function with an argument list that is created by inserting
+the method's object before the first argument.
+
+If you still don't understand how methods work, a look at the implementation can
+perhaps clarify matters. When an instance attribute is referenced that isn't a
+data attribute, its class is searched. If the name denotes a valid class
+attribute that is a function object, a method object is created by packing
+(pointers to) the instance object and the function object just found together in
+an abstract object: this is the method object. When the method object is called
+with an argument list, it is unpacked again, a new argument list is constructed
+from the instance object and the original argument list, and the function object
+is called with this new argument list.
+
+
+.. _tut-remarks:
+
+Random Remarks
+==============
+
+.. % [These should perhaps be placed more carefully...]
+
+Data attributes override method attributes with the same name; to avoid
+accidental name conflicts, which may cause hard-to-find bugs in large programs,
+it is wise to use some kind of convention that minimizes the chance of
+conflicts. Possible conventions include capitalizing method names, prefixing
+data attribute names with a small unique string (perhaps just an underscore), or
+using verbs for methods and nouns for data attributes.
+
+Data attributes may be referenced by methods as well as by ordinary users
+("clients") of an object. In other words, classes are not usable to implement
+pure abstract data types. In fact, nothing in Python makes it possible to
+enforce data hiding --- it is all based upon convention. (On the other hand,
+the Python implementation, written in C, can completely hide implementation
+details and control access to an object if necessary; this can be used by
+extensions to Python written in C.)
+
+Clients should use data attributes with care --- clients may mess up invariants
+maintained by the methods by stamping on their data attributes. Note that
+clients may add data attributes of their own to an instance object without
+affecting the validity of the methods, as long as name conflicts are avoided ---
+again, a naming convention can save a lot of headaches here.
+
+There is no shorthand for referencing data attributes (or other methods!) from
+within methods. I find that this actually increases the readability of methods:
+there is no chance of confusing local variables and instance variables when
+glancing through a method.
+
+Often, the first argument of a method is called ``self``. This is nothing more
+than a convention: the name ``self`` has absolutely no special meaning to
+Python. (Note, however, that by not following the convention your code may be
+less readable to other Python programmers, and it is also conceivable that a
+*class browser* program might be written that relies upon such a convention.)
+
+Any function object that is a class attribute defines a method for instances of
+that class. It is not necessary that the function definition is textually
+enclosed in the class definition: assigning a function object to a local
+variable in the class is also ok. For example::
+
+ # Function defined outside the class
+ def f1(self, x, y):
+ return min(x, x+y)
+
+ class C:
+ f = f1
+ def g(self):
+ return 'hello world'
+ h = g
+
+Now ``f``, ``g`` and ``h`` are all attributes of class :class:`C` that refer to
+function objects, and consequently they are all methods of instances of
+:class:`C` --- ``h`` being exactly equivalent to ``g``. Note that this practice
+usually only serves to confuse the reader of a program.
+
+Methods may call other methods by using method attributes of the ``self``
+argument::
+
+ class Bag:
+ def __init__(self):
+ self.data = []
+ def add(self, x):
+ self.data.append(x)
+ def addtwice(self, x):
+ self.add(x)
+ self.add(x)
+
+Methods may reference global names in the same way as ordinary functions. The
+global scope associated with a method is the module containing the class
+definition. (The class itself is never used as a global scope!) While one
+rarely encounters a good reason for using global data in a method, there are
+many legitimate uses of the global scope: for one thing, functions and modules
+imported into the global scope can be used by methods, as well as functions and
+classes defined in it. Usually, the class containing the method is itself
+defined in this global scope, and in the next section we'll find some good
+reasons why a method would want to reference its own class!
+
+
+.. _tut-inheritance:
+
+Inheritance
+===========
+
+Of course, a language feature would not be worthy of the name "class" without
+supporting inheritance. The syntax for a derived class definition looks like
+this::
+
+ class DerivedClassName(BaseClassName):
+ <statement-1>
+ .
+ .
+ .
+ <statement-N>
+
+The name :class:`BaseClassName` must be defined in a scope containing the
+derived class definition. In place of a base class name, other arbitrary
+expressions are also allowed. This can be useful, for example, when the base
+class is defined in another module::
+
+ class DerivedClassName(modname.BaseClassName):
+
+Execution of a derived class definition proceeds the same as for a base class.
+When the class object is constructed, the base class is remembered. This is
+used for resolving attribute references: if a requested attribute is not found
+in the class, the search proceeds to look in the base class. This rule is
+applied recursively if the base class itself is derived from some other class.
+
+There's nothing special about instantiation of derived classes:
+``DerivedClassName()`` creates a new instance of the class. Method references
+are resolved as follows: the corresponding class attribute is searched,
+descending down the chain of base classes if necessary, and the method reference
+is valid if this yields a function object.
+
+Derived classes may override methods of their base classes. Because methods
+have no special privileges when calling other methods of the same object, a
+method of a base class that calls another method defined in the same base class
+may end up calling a method of a derived class that overrides it. (For C++
+programmers: all methods in Python are effectively :keyword:`virtual`.)
+
+An overriding method in a derived class may in fact want to extend rather than
+simply replace the base class method of the same name. There is a simple way to
+call the base class method directly: just call ``BaseClassName.methodname(self,
+arguments)``. This is occasionally useful to clients as well. (Note that this
+only works if the base class is defined or imported directly in the global
+scope.)
+
+
+.. _tut-multiple:
+
+Multiple Inheritance
+--------------------
+
+Python supports a limited form of multiple inheritance as well. A class
+definition with multiple base classes looks like this::
+
+ class DerivedClassName(Base1, Base2, Base3):
+ <statement-1>
+ .
+ .
+ .
+ <statement-N>
+
+For old-style classes, the only rule is depth-first, left-to-right. Thus, if an
+attribute is not found in :class:`DerivedClassName`, it is searched in
+:class:`Base1`, then (recursively) in the base classes of :class:`Base1`, and
+only if it is not found there, it is searched in :class:`Base2`, and so on.
+
+(To some people breadth first --- searching :class:`Base2` and :class:`Base3`
+before the base classes of :class:`Base1` --- looks more natural. However, this
+would require you to know whether a particular attribute of :class:`Base1` is
+actually defined in :class:`Base1` or in one of its base classes before you can
+figure out the consequences of a name conflict with an attribute of
+:class:`Base2`. The depth-first rule makes no differences between direct and
+inherited attributes of :class:`Base1`.)
+
+For new-style classes, the method resolution order changes dynamically to
+support cooperative calls to :func:`super`. This approach is known in some
+other multiple-inheritance languages as call-next-method and is more powerful
+than the super call found in single-inheritance languages.
+
+With new-style classes, dynamic ordering is necessary because all cases of
+multiple inheritance exhibit one or more diamond relationships (where one at
+least one of the parent classes can be accessed through multiple paths from the
+bottommost class). For example, all new-style classes inherit from
+:class:`object`, so any case of multiple inheritance provides more than one path
+to reach :class:`object`. To keep the base classes from being accessed more
+than once, the dynamic algorithm linearizes the search order in a way that
+preserves the left-to-right ordering specified in each class, that calls each
+parent only once, and that is monotonic (meaning that a class can be subclassed
+without affecting the precedence order of its parents). Taken together, these
+properties make it possible to design reliable and extensible classes with
+multiple inheritance. For more detail, see
+http://www.python.org/download/releases/2.3/mro/.
+
+
+.. _tut-private:
+
+Private Variables
+=================
+
+There is limited support for class-private identifiers. Any identifier of the
+form ``__spam`` (at least two leading underscores, at most one trailing
+underscore) is textually replaced with ``_classname__spam``, where ``classname``
+is the current class name with leading underscore(s) stripped. This mangling is
+done without regard to the syntactic position of the identifier, so it can be
+used to define class-private instance and class variables, methods, variables
+stored in globals, and even variables stored in instances. private to this class
+on instances of *other* classes. Truncation may occur when the mangled name
+would be longer than 255 characters. Outside classes, or when the class name
+consists of only underscores, no mangling occurs.
+
+Name mangling is intended to give classes an easy way to define "private"
+instance variables and methods, without having to worry about instance variables
+defined by derived classes, or mucking with instance variables by code outside
+the class. Note that the mangling rules are designed mostly to avoid accidents;
+it still is possible for a determined soul to access or modify a variable that
+is considered private. This can even be useful in special circumstances, such
+as in the debugger, and that's one reason why this loophole is not closed.
+(Buglet: derivation of a class with the same name as the base class makes use of
+private variables of the base class possible.)
+
+Notice that code passed to ``exec()`` or ``eval()`` does not
+consider the classname of the invoking class to be the current class; this is
+similar to the effect of the ``global`` statement, the effect of which is
+likewise restricted to code that is byte-compiled together. The same
+restriction applies to ``getattr()``, ``setattr()`` and ``delattr()``, as well
+as when referencing ``__dict__`` directly.
+
+
+.. _tut-odds:
+
+Odds and Ends
+=============
+
+Sometimes it is useful to have a data type similar to the Pascal "record" or C
+"struct", bundling together a few named data items. An empty class definition
+will do nicely::
+
+ class Employee:
+ pass
+
+ john = Employee() # Create an empty employee record
+
+ # Fill the fields of the record
+ john.name = 'John Doe'
+ john.dept = 'computer lab'
+ john.salary = 1000
+
+A piece of Python code that expects a particular abstract data type can often be
+passed a class that emulates the methods of that data type instead. For
+instance, if you have a function that formats some data from a file object, you
+can define a class with methods :meth:`read` and :meth:`readline` that get the
+data from a string buffer instead, and pass it as an argument.
+
+.. % (Unfortunately, this
+.. % technique has its limitations: a class can't define operations that
+.. % are accessed by special syntax such as sequence subscripting or
+.. % arithmetic operators, and assigning such a ``pseudo-file'' to
+.. % \code{sys.stdin} will not cause the interpreter to read further input
+.. % from it.)
+
+Instance method objects have attributes, too: ``m.im_self`` is the instance
+object with the method :meth:`m`, and ``m.im_func`` is the function object
+corresponding to the method.
+
+
+.. _tut-exceptionclasses:
+
+Exceptions Are Classes Too
+==========================
+
+User-defined exceptions are identified by classes as well. Using this mechanism
+it is possible to create extensible hierarchies of exceptions.
+
+There are two new valid (semantic) forms for the raise statement::
+
+ raise Class, instance
+
+ raise instance
+
+In the first form, ``instance`` must be an instance of :class:`Class` or of a
+class derived from it. The second form is a shorthand for::
+
+ raise instance.__class__, instance
+
+A class in an except clause is compatible with an exception if it is the same
+class or a base class thereof (but not the other way around --- an except clause
+listing a derived class is not compatible with a base class). For example, the
+following code will print B, C, D in that order::
+
+ class B:
+ pass
+ class C(B):
+ pass
+ class D(C):
+ pass
+
+ for c in [B, C, D]:
+ try:
+ raise c()
+ except D:
+ print "D"
+ except C:
+ print "C"
+ except B:
+ print "B"
+
+Note that if the except clauses were reversed (with ``except B`` first), it
+would have printed B, B, B --- the first matching except clause is triggered.
+
+When an error message is printed for an unhandled exception, the exception's
+class name is printed, then a colon and a space, and finally the instance
+converted to a string using the built-in function :func:`str`.
+
+
+.. _tut-iterators:
+
+Iterators
+=========
+
+By now you have probably noticed that most container objects can be looped over
+using a :keyword:`for` statement::
+
+ for element in [1, 2, 3]:
+ print element
+ for element in (1, 2, 3):
+ print element
+ for key in {'one':1, 'two':2}:
+ print key
+ for char in "123":
+ print char
+ for line in open("myfile.txt"):
+ print line
+
+This style of access is clear, concise, and convenient. The use of iterators
+pervades and unifies Python. Behind the scenes, the :keyword:`for` statement
+calls :func:`iter` on the container object. The function returns an iterator
+object that defines the method :meth:`__next__` which accesses elements in the
+container one at a time. When there are no more elements, :meth:`__next__`
+raises a :exc:`StopIteration` exception which tells the :keyword:`for` loop to
+terminate. You can call the :meth:`__next__` method using the :func:`next`
+builtin; this example shows how it all works::
+
+ >>> s = 'abc'
+ >>> it = iter(s)
+ >>> it
+ <iterator object at 0x00A1DB50>
+ >>> next(it)
+ 'a'
+ >>> next(it)
+ 'b'
+ >>> next(it)
+ 'c'
+ >>> next(it)
+
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ next(it)
+ StopIteration
+
+Having seen the mechanics behind the iterator protocol, it is easy to add
+iterator behavior to your classes. Define a :meth:`__iter__` method which
+returns an object with a :meth:`__next__` method. If the class defines
+:meth:`__next__`, then :meth:`__iter__` can just return ``self``::
+
+ class Reverse:
+ "Iterator for looping over a sequence backwards"
+ def __init__(self, data):
+ self.data = data
+ self.index = len(data)
+ def __iter__(self):
+ return self
+ def __next__(self):
+ if self.index == 0:
+ raise StopIteration
+ self.index = self.index - 1
+ return self.data[self.index]
+
+ >>> for char in Reverse('spam'):
+ ... print char
+ ...
+ m
+ a
+ p
+ s
+
+
+.. _tut-generators:
+
+Generators
+==========
+
+Generators are a simple and powerful tool for creating iterators. They are
+written like regular functions but use the :keyword:`yield` statement whenever
+they want to return data. Each time :func:`next` is called on it, the generator
+resumes where it left-off (it remembers all the data values and which statement
+was last executed). An example shows that generators can be trivially easy to
+create::
+
+ def reverse(data):
+ for index in range(len(data)-1, -1, -1):
+ yield data[index]
+
+ >>> for char in reverse('golf'):
+ ... print char
+ ...
+ f
+ l
+ o
+ g
+
+Anything that can be done with generators can also be done with class based
+iterators as described in the previous section. What makes generators so
+compact is that the :meth:`__iter__` and :meth:`__next__` methods are created
+automatically.
+
+Another key feature is that the local variables and execution state are
+automatically saved between calls. This made the function easier to write and
+much more clear than an approach using instance variables like ``self.index``
+and ``self.data``.
+
+In addition to automatic method creation and saving program state, when
+generators terminate, they automatically raise :exc:`StopIteration`. In
+combination, these features make it easy to create iterators with no more effort
+than writing a regular function.
+
+
+.. _tut-genexps:
+
+Generator Expressions
+=====================
+
+Some simple generators can be coded succinctly as expressions using a syntax
+similar to list comprehensions but with parentheses instead of brackets. These
+expressions are designed for situations where the generator is used right away
+by an enclosing function. Generator expressions are more compact but less
+versatile than full generator definitions and tend to be more memory friendly
+than equivalent list comprehensions.
+
+Examples::
+
+ >>> sum(i*i for i in range(10)) # sum of squares
+ 285
+
+ >>> xvec = [10, 20, 30]
+ >>> yvec = [7, 5, 3]
+ >>> sum(x*y for x,y in zip(xvec, yvec)) # dot product
+ 260
+
+ >>> from math import pi, sin
+ >>> sine_table = dict((x, sin(x*pi/180)) for x in range(0, 91))
+
+ >>> unique_words = set(word for line in page for word in line.split())
+
+ >>> valedictorian = max((student.gpa, student.name) for student in graduates)
+
+ >>> data = 'golf'
+ >>> list(data[i] for i in range(len(data)-1,-1,-1))
+ ['f', 'l', 'o', 'g']
+
+
+
+.. rubric:: Footnotes
+
+.. [#] Except for one thing. Module objects have a secret read-only attribute called
+ :attr:`__dict__` which returns the dictionary used to implement the module's
+ namespace; the name :attr:`__dict__` is an attribute but not a global name.
+ Obviously, using this violates the abstraction of namespace implementation, and
+ should be restricted to things like post-mortem debuggers.
+
diff --git a/Doc/tutorial/controlflow.rst b/Doc/tutorial/controlflow.rst
new file mode 100644
index 0000000000..f6f41b33b7
--- /dev/null
+++ b/Doc/tutorial/controlflow.rst
@@ -0,0 +1,574 @@
+.. _tut-morecontrol:
+
+***********************
+More Control Flow Tools
+***********************
+
+Besides the :keyword:`while` statement just introduced, Python knows the usual
+control flow statements known from other languages, with some twists.
+
+
+.. _tut-if:
+
+:keyword:`if` Statements
+========================
+
+Perhaps the most well-known statement type is the :keyword:`if` statement. For
+example::
+
+ >>> def raw_input(prompt):
+ ... import sys
+ ... sys.stdout.write(prompt)
+ ... sys.stdout.flush()
+ ... return sys.stdin.readline()
+ ...
+ >>> x = int(raw_input("Please enter an integer: "))
+ >>> if x < 0:
+ ... x = 0
+ ... print 'Negative changed to zero'
+ ... elif x == 0:
+ ... print 'Zero'
+ ... elif x == 1:
+ ... print 'Single'
+ ... else:
+ ... print 'More'
+ ...
+
+There can be zero or more :keyword:`elif` parts, and the :keyword:`else` part is
+optional. The keyword ':keyword:`elif`' is short for 'else if', and is useful
+to avoid excessive indentation. An :keyword:`if` ... :keyword:`elif` ...
+:keyword:`elif` ... sequence is a substitute for the :keyword:`switch` or
+:keyword:`case` statements found in other languages.
+
+.. % Weird spacings happen here if the wrapping of the source text
+.. % gets changed in the wrong way.
+
+
+.. _tut-for:
+
+:keyword:`for` Statements
+=========================
+
+.. index::
+ statement: for
+ statement: for
+
+The :keyword:`for` statement in Python differs a bit from what you may be used
+to in C or Pascal. Rather than always iterating over an arithmetic progression
+of numbers (like in Pascal), or giving the user the ability to define both the
+iteration step and halting condition (as C), Python's :keyword:`for` statement
+iterates over the items of any sequence (a list or a string), in the order that
+they appear in the sequence. For example (no pun intended):
+
+.. % One suggestion was to give a real C example here, but that may only
+.. % serve to confuse non-C programmers.
+
+::
+
+ >>> # Measure some strings:
+ ... a = ['cat', 'window', 'defenestrate']
+ >>> for x in a:
+ ... print x, len(x)
+ ...
+ cat 3
+ window 6
+ defenestrate 12
+
+It is not safe to modify the sequence being iterated over in the loop (this can
+only happen for mutable sequence types, such as lists). If you need to modify
+the list you are iterating over (for example, to duplicate selected items) you
+must iterate over a copy. The slice notation makes this particularly
+convenient::
+
+ >>> for x in a[:]: # make a slice copy of the entire list
+ ... if len(x) > 6: a.insert(0, x)
+ ...
+ >>> a
+ ['defenestrate', 'cat', 'window', 'defenestrate']
+
+
+.. _tut-range:
+
+The :func:`range` Function
+==========================
+
+If you do need to iterate over a sequence of numbers, the built-in function
+:func:`range` comes in handy. It generates lists containing arithmetic
+progressions::
+
+ >>> range(10)
+ [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+
+The given end point is never part of the generated list; ``range(10)`` generates
+a list of 10 values, the legal indices for items of a sequence of length 10. It
+is possible to let the range start at another number, or to specify a different
+increment (even negative; sometimes this is called the 'step')::
+
+ >>> range(5, 10)
+ [5, 6, 7, 8, 9]
+ >>> range(0, 10, 3)
+ [0, 3, 6, 9]
+ >>> range(-10, -100, -30)
+ [-10, -40, -70]
+
+To iterate over the indices of a sequence, combine :func:`range` and :func:`len`
+as follows::
+
+ >>> a = ['Mary', 'had', 'a', 'little', 'lamb']
+ >>> for i in range(len(a)):
+ ... print i, a[i]
+ ...
+ 0 Mary
+ 1 had
+ 2 a
+ 3 little
+ 4 lamb
+
+
+.. _tut-break:
+
+:keyword:`break` and :keyword:`continue` Statements, and :keyword:`else` Clauses on Loops
+=========================================================================================
+
+The :keyword:`break` statement, like in C, breaks out of the smallest enclosing
+:keyword:`for` or :keyword:`while` loop.
+
+The :keyword:`continue` statement, also borrowed from C, continues with the next
+iteration of the loop.
+
+Loop statements may have an ``else`` clause; it is executed when the loop
+terminates through exhaustion of the list (with :keyword:`for`) or when the
+condition becomes false (with :keyword:`while`), but not when the loop is
+terminated by a :keyword:`break` statement. This is exemplified by the
+following loop, which searches for prime numbers::
+
+ >>> for n in range(2, 10):
+ ... for x in range(2, n):
+ ... if n % x == 0:
+ ... print n, 'equals', x, '*', n/x
+ ... break
+ ... else:
+ ... # loop fell through without finding a factor
+ ... print n, 'is a prime number'
+ ...
+ 2 is a prime number
+ 3 is a prime number
+ 4 equals 2 * 2
+ 5 is a prime number
+ 6 equals 2 * 3
+ 7 is a prime number
+ 8 equals 2 * 4
+ 9 equals 3 * 3
+
+
+.. _tut-pass:
+
+:keyword:`pass` Statements
+==========================
+
+The :keyword:`pass` statement does nothing. It can be used when a statement is
+required syntactically but the program requires no action. For example::
+
+ >>> while True:
+ ... pass # Busy-wait for keyboard interrupt
+ ...
+
+
+.. _tut-functions:
+
+Defining Functions
+==================
+
+We can create a function that writes the Fibonacci series to an arbitrary
+boundary::
+
+ >>> def fib(n): # write Fibonacci series up to n
+ ... """Print a Fibonacci series up to n."""
+ ... a, b = 0, 1
+ ... while b < n:
+ ... print b,
+ ... a, b = b, a+b
+ ...
+ >>> # Now call the function we just defined:
+ ... fib(2000)
+ 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 1597
+
+.. index::
+ single: documentation strings
+ single: docstrings
+ single: strings, documentation
+
+The keyword :keyword:`def` introduces a function *definition*. It must be
+followed by the function name and the parenthesized list of formal parameters.
+The statements that form the body of the function start at the next line, and
+must be indented. The first statement of the function body can optionally be a
+string literal; this string literal is the function's documentation string, or
+:dfn:`docstring`.
+
+There are tools which use docstrings to automatically produce online or printed
+documentation, or to let the user interactively browse through code; it's good
+practice to include docstrings in code that you write, so try to make a habit of
+it.
+
+The *execution* of a function introduces a new symbol table used for the local
+variables of the function. More precisely, all variable assignments in a
+function store the value in the local symbol table; whereas variable references
+first look in the local symbol table, then in the global symbol table, and then
+in the table of built-in names. Thus, global variables cannot be directly
+assigned a value within a function (unless named in a :keyword:`global`
+statement), although they may be referenced.
+
+The actual parameters (arguments) to a function call are introduced in the local
+symbol table of the called function when it is called; thus, arguments are
+passed using *call by value* (where the *value* is always an object *reference*,
+not the value of the object). [#]_ When a function calls another function, a new
+local symbol table is created for that call.
+
+A function definition introduces the function name in the current symbol table.
+The value of the function name has a type that is recognized by the interpreter
+as a user-defined function. This value can be assigned to another name which
+can then also be used as a function. This serves as a general renaming
+mechanism::
+
+ >>> fib
+ <function fib at 10042ed0>
+ >>> f = fib
+ >>> f(100)
+ 1 1 2 3 5 8 13 21 34 55 89
+
+You might object that ``fib`` is not a function but a procedure. In Python,
+like in C, procedures are just functions that don't return a value. In fact,
+technically speaking, procedures do return a value, albeit a rather boring one.
+This value is called ``None`` (it's a built-in name). Writing the value
+``None`` is normally suppressed by the interpreter if it would be the only value
+written. You can see it if you really want to::
+
+ >>> print fib(0)
+ None
+
+It is simple to write a function that returns a list of the numbers of the
+Fibonacci series, instead of printing it::
+
+ >>> def fib2(n): # return Fibonacci series up to n
+ ... """Return a list containing the Fibonacci series up to n."""
+ ... result = []
+ ... a, b = 0, 1
+ ... while b < n:
+ ... result.append(b) # see below
+ ... a, b = b, a+b
+ ... return result
+ ...
+ >>> f100 = fib2(100) # call it
+ >>> f100 # write the result
+ [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
+
+This example, as usual, demonstrates some new Python features:
+
+* The :keyword:`return` statement returns with a value from a function.
+ :keyword:`return` without an expression argument returns ``None``. Falling off
+ the end of a procedure also returns ``None``.
+
+* The statement ``result.append(b)`` calls a *method* of the list object
+ ``result``. A method is a function that 'belongs' to an object and is named
+ ``obj.methodname``, where ``obj`` is some object (this may be an expression),
+ and ``methodname`` is the name of a method that is defined by the object's type.
+ Different types define different methods. Methods of different types may have
+ the same name without causing ambiguity. (It is possible to define your own
+ object types and methods, using *classes*, as discussed later in this tutorial.)
+ The method :meth:`append` shown in the example is defined for list objects; it
+ adds a new element at the end of the list. In this example it is equivalent to
+ ``result = result + [b]``, but more efficient.
+
+
+.. _tut-defining:
+
+More on Defining Functions
+==========================
+
+It is also possible to define functions with a variable number of arguments.
+There are three forms, which can be combined.
+
+
+.. _tut-defaultargs:
+
+Default Argument Values
+-----------------------
+
+The most useful form is to specify a default value for one or more arguments.
+This creates a function that can be called with fewer arguments than it is
+defined to allow. For example::
+
+ def raw_input(prompt):
+ import sys
+ sys.stdout.write(prompt)
+ sys.stdout.flush()
+ return sys.stdin.readline()
+
+ def ask_ok(prompt, retries=4, complaint='Yes or no, please!'):
+ while True:
+ ok = raw_input(prompt)
+ if ok in ('y', 'ye', 'yes'): return True
+ if ok in ('n', 'no', 'nop', 'nope'): return False
+ retries = retries - 1
+ if retries < 0: raise IOError, 'refusenik user'
+ print complaint
+
+This function can be called either like this: ``ask_ok('Do you really want to
+quit?')`` or like this: ``ask_ok('OK to overwrite the file?', 2)``.
+
+This example also introduces the :keyword:`in` keyword. This tests whether or
+not a sequence contains a certain value.
+
+The default values are evaluated at the point of function definition in the
+*defining* scope, so that ::
+
+ i = 5
+
+ def f(arg=i):
+ print arg
+
+ i = 6
+ f()
+
+will print ``5``.
+
+**Important warning:** The default value is evaluated only once. This makes a
+difference when the default is a mutable object such as a list, dictionary, or
+instances of most classes. For example, the following function accumulates the
+arguments passed to it on subsequent calls::
+
+ def f(a, L=[]):
+ L.append(a)
+ return L
+
+ print f(1)
+ print f(2)
+ print f(3)
+
+This will print ::
+
+ [1]
+ [1, 2]
+ [1, 2, 3]
+
+If you don't want the default to be shared between subsequent calls, you can
+write the function like this instead::
+
+ def f(a, L=None):
+ if L is None:
+ L = []
+ L.append(a)
+ return L
+
+
+.. _tut-keywordargs:
+
+Keyword Arguments
+-----------------
+
+Functions can also be called using keyword arguments of the form ``keyword =
+value``. For instance, the following function::
+
+ def parrot(voltage, state='a stiff', action='voom', type='Norwegian Blue'):
+ print "-- This parrot wouldn't", action,
+ print "if you put", voltage, "volts through it."
+ print "-- Lovely plumage, the", type
+ print "-- It's", state, "!"
+
+could be called in any of the following ways::
+
+ parrot(1000)
+ parrot(action = 'VOOOOOM', voltage = 1000000)
+ parrot('a thousand', state = 'pushing up the daisies')
+ parrot('a million', 'bereft of life', 'jump')
+
+but the following calls would all be invalid::
+
+ parrot() # required argument missing
+ parrot(voltage=5.0, 'dead') # non-keyword argument following keyword
+ parrot(110, voltage=220) # duplicate value for argument
+ parrot(actor='John Cleese') # unknown keyword
+
+In general, an argument list must have any positional arguments followed by any
+keyword arguments, where the keywords must be chosen from the formal parameter
+names. It's not important whether a formal parameter has a default value or
+not. No argument may receive a value more than once --- formal parameter names
+corresponding to positional arguments cannot be used as keywords in the same
+calls. Here's an example that fails due to this restriction::
+
+ >>> def function(a):
+ ... pass
+ ...
+ >>> function(0, a=0)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: function() got multiple values for keyword argument 'a'
+
+When a final formal parameter of the form ``**name`` is present, it receives a
+dictionary (see :ref:`typesmapping`) containing all keyword arguments except for
+those corresponding to a formal parameter. This may be combined with a formal
+parameter of the form ``*name`` (described in the next subsection) which
+receives a tuple containing the positional arguments beyond the formal parameter
+list. (``*name`` must occur before ``**name``.) For example, if we define a
+function like this::
+
+ def cheeseshop(kind, *arguments, **keywords):
+ print "-- Do you have any", kind, '?'
+ print "-- I'm sorry, we're all out of", kind
+ for arg in arguments: print arg
+ print '-'*40
+ keys = keywords.keys()
+ keys.sort()
+ for kw in keys: print kw, ':', keywords[kw]
+
+It could be called like this::
+
+ cheeseshop('Limburger', "It's very runny, sir.",
+ "It's really very, VERY runny, sir.",
+ client='John Cleese',
+ shopkeeper='Michael Palin',
+ sketch='Cheese Shop Sketch')
+
+and of course it would print::
+
+ -- Do you have any Limburger ?
+ -- I'm sorry, we're all out of Limburger
+ It's very runny, sir.
+ It's really very, VERY runny, sir.
+ ----------------------------------------
+ client : John Cleese
+ shopkeeper : Michael Palin
+ sketch : Cheese Shop Sketch
+
+Note that the :meth:`sort` method of the list of keyword argument names is
+called before printing the contents of the ``keywords`` dictionary; if this is
+not done, the order in which the arguments are printed is undefined.
+
+
+.. _tut-arbitraryargs:
+
+Arbitrary Argument Lists
+------------------------
+
+Finally, the least frequently used option is to specify that a function can be
+called with an arbitrary number of arguments. These arguments will be wrapped
+up in a tuple. Before the variable number of arguments, zero or more normal
+arguments may occur. ::
+
+ def fprintf(file, format, *args):
+ file.write(format % args)
+
+
+.. _tut-unpacking-arguments:
+
+Unpacking Argument Lists
+------------------------
+
+The reverse situation occurs when the arguments are already in a list or tuple
+but need to be unpacked for a function call requiring separate positional
+arguments. For instance, the built-in :func:`range` function expects separate
+*start* and *stop* arguments. If they are not available separately, write the
+function call with the ``*``\ -operator to unpack the arguments out of a list
+or tuple::
+
+ >>> range(3, 6) # normal call with separate arguments
+ [3, 4, 5]
+ >>> args = [3, 6]
+ >>> range(*args) # call with arguments unpacked from a list
+ [3, 4, 5]
+
+In the same fashion, dictionaries can deliver keyword arguments with the ``**``\
+-operator::
+
+ >>> def parrot(voltage, state='a stiff', action='voom'):
+ ... print "-- This parrot wouldn't", action,
+ ... print "if you put", voltage, "volts through it.",
+ ... print "E's", state, "!"
+ ...
+ >>> d = {"voltage": "four million", "state": "bleedin' demised", "action": "VOOM"}
+ >>> parrot(**d)
+ -- This parrot wouldn't VOOM if you put four million volts through it. E's bleedin' demised !
+
+
+.. _tut-lambda:
+
+Lambda Forms
+------------
+
+By popular demand, a few features commonly found in functional programming
+languages like Lisp have been added to Python. With the :keyword:`lambda`
+keyword, small anonymous functions can be created. Here's a function that
+returns the sum of its two arguments: ``lambda a, b: a+b``. Lambda forms can be
+used wherever function objects are required. They are syntactically restricted
+to a single expression. Semantically, they are just syntactic sugar for a
+normal function definition. Like nested function definitions, lambda forms can
+reference variables from the containing scope::
+
+ >>> def make_incrementor(n):
+ ... return lambda x: x + n
+ ...
+ >>> f = make_incrementor(42)
+ >>> f(0)
+ 42
+ >>> f(1)
+ 43
+
+
+.. _tut-docstrings:
+
+Documentation Strings
+---------------------
+
+.. index::
+ single: docstrings
+ single: documentation strings
+ single: strings, documentation
+
+There are emerging conventions about the content and formatting of documentation
+strings.
+
+The first line should always be a short, concise summary of the object's
+purpose. For brevity, it should not explicitly state the object's name or type,
+since these are available by other means (except if the name happens to be a
+verb describing a function's operation). This line should begin with a capital
+letter and end with a period.
+
+If there are more lines in the documentation string, the second line should be
+blank, visually separating the summary from the rest of the description. The
+following lines should be one or more paragraphs describing the object's calling
+conventions, its side effects, etc.
+
+The Python parser does not strip indentation from multi-line string literals in
+Python, so tools that process documentation have to strip indentation if
+desired. This is done using the following convention. The first non-blank line
+*after* the first line of the string determines the amount of indentation for
+the entire documentation string. (We can't use the first line since it is
+generally adjacent to the string's opening quotes so its indentation is not
+apparent in the string literal.) Whitespace "equivalent" to this indentation is
+then stripped from the start of all lines of the string. Lines that are
+indented less should not occur, but if they occur all their leading whitespace
+should be stripped. Equivalence of whitespace should be tested after expansion
+of tabs (to 8 spaces, normally).
+
+Here is an example of a multi-line docstring::
+
+ >>> def my_function():
+ ... """Do nothing, but document it.
+ ...
+ ... No, really, it doesn't do anything.
+ ... """
+ ... pass
+ ...
+ >>> print my_function.__doc__
+ Do nothing, but document it.
+
+ No, really, it doesn't do anything.
+
+
+
+.. rubric:: Footnotes
+
+.. [#] Actually, *call by object reference* would be a better description, since if a
+ mutable object is passed, the caller will see any changes the callee makes to it
+ (items inserted into a list).
+
diff --git a/Doc/tutorial/datastructures.rst b/Doc/tutorial/datastructures.rst
new file mode 100644
index 0000000000..d65e55b1f5
--- /dev/null
+++ b/Doc/tutorial/datastructures.rst
@@ -0,0 +1,586 @@
+.. _tut-structures:
+
+***************
+Data Structures
+***************
+
+This chapter describes some things you've learned about already in more detail,
+and adds some new things as well.
+
+
+.. _tut-morelists:
+
+More on Lists
+=============
+
+The list data type has some more methods. Here are all of the methods of list
+objects:
+
+
+.. method:: list.append(x)
+
+ Add an item to the end of the list; equivalent to ``a[len(a):] = [x]``.
+
+
+.. method:: list.extend(L)
+
+ Extend the list by appending all the items in the given list; equivalent to
+ ``a[len(a):] = L``.
+
+
+.. method:: list.insert(i, x)
+
+ Insert an item at a given position. The first argument is the index of the
+ element before which to insert, so ``a.insert(0, x)`` inserts at the front of
+ the list, and ``a.insert(len(a), x)`` is equivalent to ``a.append(x)``.
+
+
+.. method:: list.remove(x)
+
+ Remove the first item from the list whose value is *x*. It is an error if there
+ is no such item.
+
+
+.. method:: list.pop([i])
+
+ Remove the item at the given position in the list, and return it. If no index
+ is specified, ``a.pop()`` removes and returns the last item in the list. (The
+ square brackets around the *i* in the method signature denote that the parameter
+ is optional, not that you should type square brackets at that position. You
+ will see this notation frequently in the Python Library Reference.)
+
+
+.. method:: list.index(x)
+
+ Return the index in the list of the first item whose value is *x*. It is an
+ error if there is no such item.
+
+
+.. method:: list.count(x)
+
+ Return the number of times *x* appears in the list.
+
+
+.. method:: list.sort()
+
+ Sort the items of the list, in place.
+
+
+.. method:: list.reverse()
+
+ Reverse the elements of the list, in place.
+
+An example that uses most of the list methods::
+
+ >>> a = [66.25, 333, 333, 1, 1234.5]
+ >>> print a.count(333), a.count(66.25), a.count('x')
+ 2 1 0
+ >>> a.insert(2, -1)
+ >>> a.append(333)
+ >>> a
+ [66.25, 333, -1, 333, 1, 1234.5, 333]
+ >>> a.index(333)
+ 1
+ >>> a.remove(333)
+ >>> a
+ [66.25, -1, 333, 1, 1234.5, 333]
+ >>> a.reverse()
+ >>> a
+ [333, 1234.5, 1, 333, -1, 66.25]
+ >>> a.sort()
+ >>> a
+ [-1, 1, 66.25, 333, 333, 1234.5]
+
+
+.. _tut-lists-as-stacks:
+
+Using Lists as Stacks
+---------------------
+
+.. sectionauthor:: Ka-Ping Yee <ping@lfw.org>
+
+
+The list methods make it very easy to use a list as a stack, where the last
+element added is the first element retrieved ("last-in, first-out"). To add an
+item to the top of the stack, use :meth:`append`. To retrieve an item from the
+top of the stack, use :meth:`pop` without an explicit index. For example::
+
+ >>> stack = [3, 4, 5]
+ >>> stack.append(6)
+ >>> stack.append(7)
+ >>> stack
+ [3, 4, 5, 6, 7]
+ >>> stack.pop()
+ 7
+ >>> stack
+ [3, 4, 5, 6]
+ >>> stack.pop()
+ 6
+ >>> stack.pop()
+ 5
+ >>> stack
+ [3, 4]
+
+
+.. _tut-lists-as-queues:
+
+Using Lists as Queues
+---------------------
+
+.. sectionauthor:: Ka-Ping Yee <ping@lfw.org>
+
+
+You can also use a list conveniently as a queue, where the first element added
+is the first element retrieved ("first-in, first-out"). To add an item to the
+back of the queue, use :meth:`append`. To retrieve an item from the front of
+the queue, use :meth:`pop` with ``0`` as the index. For example::
+
+ >>> queue = ["Eric", "John", "Michael"]
+ >>> queue.append("Terry") # Terry arrives
+ >>> queue.append("Graham") # Graham arrives
+ >>> queue.pop(0)
+ 'Eric'
+ >>> queue.pop(0)
+ 'John'
+ >>> queue
+ ['Michael', 'Terry', 'Graham']
+
+
+.. _tut-functional:
+
+Functional Programming Tools
+----------------------------
+
+There are two built-in functions that are very useful when used with lists:
+:func:`filter` and :func:`map`.
+
+``filter(function, sequence)`` returns a sequence consisting of those items from
+the sequence for which ``function(item)`` is true. If *sequence* is a
+:class:`string` or :class:`tuple`, the result will be of the same type;
+otherwise, it is always a :class:`list`. For example, to compute some primes::
+
+ >>> def f(x): return x % 2 != 0 and x % 3 != 0
+ ...
+ >>> filter(f, range(2, 25))
+ [5, 7, 11, 13, 17, 19, 23]
+
+``map(function, sequence)`` calls ``function(item)`` for each of the sequence's
+items and returns a list of the return values. For example, to compute some
+cubes::
+
+ >>> def cube(x): return x*x*x
+ ...
+ >>> map(cube, range(1, 11))
+ [1, 8, 27, 64, 125, 216, 343, 512, 729, 1000]
+
+More than one sequence may be passed; the function must then have as many
+arguments as there are sequences and is called with the corresponding item from
+each sequence (or ``None`` if some sequence is shorter than another). For
+example::
+
+ >>> seq = range(8)
+ >>> def add(x, y): return x+y
+ ...
+ >>> map(add, seq, seq)
+ [0, 2, 4, 6, 8, 10, 12, 14]
+
+.. versionadded:: 2.3
+
+
+List Comprehensions
+-------------------
+
+List comprehensions provide a concise way to create lists without resorting to
+use of :func:`map`, :func:`filter` and/or :keyword:`lambda`. The resulting list
+definition tends often to be clearer than lists built using those constructs.
+Each list comprehension consists of an expression followed by a :keyword:`for`
+clause, then zero or more :keyword:`for` or :keyword:`if` clauses. The result
+will be a list resulting from evaluating the expression in the context of the
+:keyword:`for` and :keyword:`if` clauses which follow it. If the expression
+would evaluate to a tuple, it must be parenthesized. ::
+
+ >>> freshfruit = [' banana', ' loganberry ', 'passion fruit ']
+ >>> [weapon.strip() for weapon in freshfruit]
+ ['banana', 'loganberry', 'passion fruit']
+ >>> vec = [2, 4, 6]
+ >>> [3*x for x in vec]
+ [6, 12, 18]
+ >>> [3*x for x in vec if x > 3]
+ [12, 18]
+ >>> [3*x for x in vec if x < 2]
+ []
+ >>> [[x,x**2] for x in vec]
+ [[2, 4], [4, 16], [6, 36]]
+ >>> [x, x**2 for x in vec] # error - parens required for tuples
+ File "<stdin>", line 1, in ?
+ [x, x**2 for x in vec]
+ ^
+ SyntaxError: invalid syntax
+ >>> [(x, x**2) for x in vec]
+ [(2, 4), (4, 16), (6, 36)]
+ >>> vec1 = [2, 4, 6]
+ >>> vec2 = [4, 3, -9]
+ >>> [x*y for x in vec1 for y in vec2]
+ [8, 6, -18, 16, 12, -36, 24, 18, -54]
+ >>> [x+y for x in vec1 for y in vec2]
+ [6, 5, -7, 8, 7, -5, 10, 9, -3]
+ >>> [vec1[i]*vec2[i] for i in range(len(vec1))]
+ [8, 12, -54]
+
+List comprehensions are much more flexible than :func:`map` and can be applied
+to complex expressions and nested functions::
+
+ >>> [str(round(355/113.0, i)) for i in range(1,6)]
+ ['3.1', '3.14', '3.142', '3.1416', '3.14159']
+
+
+.. _tut-del:
+
+The :keyword:`del` statement
+============================
+
+There is a way to remove an item from a list given its index instead of its
+value: the :keyword:`del` statement. This differs from the :meth:`pop` method
+which returns a value. The :keyword:`del` statement can also be used to remove
+slices from a list or clear the entire list (which we did earlier by assignment
+of an empty list to the slice). For example::
+
+ >>> a = [-1, 1, 66.25, 333, 333, 1234.5]
+ >>> del a[0]
+ >>> a
+ [1, 66.25, 333, 333, 1234.5]
+ >>> del a[2:4]
+ >>> a
+ [1, 66.25, 1234.5]
+ >>> del a[:]
+ >>> a
+ []
+
+:keyword:`del` can also be used to delete entire variables::
+
+ >>> del a
+
+Referencing the name ``a`` hereafter is an error (at least until another value
+is assigned to it). We'll find other uses for :keyword:`del` later.
+
+
+.. _tut-tuples:
+
+Tuples and Sequences
+====================
+
+We saw that lists and strings have many common properties, such as indexing and
+slicing operations. They are two examples of *sequence* data types (see
+:ref:`typesseq`). Since Python is an evolving language, other sequence data
+types may be added. There is also another standard sequence data type: the
+*tuple*.
+
+A tuple consists of a number of values separated by commas, for instance::
+
+ >>> t = 12345, 54321, 'hello!'
+ >>> t[0]
+ 12345
+ >>> t
+ (12345, 54321, 'hello!')
+ >>> # Tuples may be nested:
+ ... u = t, (1, 2, 3, 4, 5)
+ >>> u
+ ((12345, 54321, 'hello!'), (1, 2, 3, 4, 5))
+
+As you see, on output tuples are always enclosed in parentheses, so that nested
+tuples are interpreted correctly; they may be input with or without surrounding
+parentheses, although often parentheses are necessary anyway (if the tuple is
+part of a larger expression).
+
+Tuples have many uses. For example: (x, y) coordinate pairs, employee records
+from a database, etc. Tuples, like strings, are immutable: it is not possible
+to assign to the individual items of a tuple (you can simulate much of the same
+effect with slicing and concatenation, though). It is also possible to create
+tuples which contain mutable objects, such as lists.
+
+A special problem is the construction of tuples containing 0 or 1 items: the
+syntax has some extra quirks to accommodate these. Empty tuples are constructed
+by an empty pair of parentheses; a tuple with one item is constructed by
+following a value with a comma (it is not sufficient to enclose a single value
+in parentheses). Ugly, but effective. For example::
+
+ >>> empty = ()
+ >>> singleton = 'hello', # <-- note trailing comma
+ >>> len(empty)
+ 0
+ >>> len(singleton)
+ 1
+ >>> singleton
+ ('hello',)
+
+The statement ``t = 12345, 54321, 'hello!'`` is an example of *tuple packing*:
+the values ``12345``, ``54321`` and ``'hello!'`` are packed together in a tuple.
+The reverse operation is also possible::
+
+ >>> x, y, z = t
+
+This is called, appropriately enough, *sequence unpacking*. Sequence unpacking
+requires the list of variables on the left to have the same number of elements
+as the length of the sequence. Note that multiple assignment is really just a
+combination of tuple packing and sequence unpacking!
+
+There is a small bit of asymmetry here: packing multiple values always creates
+a tuple, and unpacking works for any sequence.
+
+.. % XXX Add a bit on the difference between tuples and lists.
+
+
+.. _tut-sets:
+
+Sets
+====
+
+Python also includes a data type for *sets*. A set is an unordered collection
+with no duplicate elements. Basic uses include membership testing and
+eliminating duplicate entries. Set objects also support mathematical operations
+like union, intersection, difference, and symmetric difference.
+
+Here is a brief demonstration::
+
+ >>> basket = ['apple', 'orange', 'apple', 'pear', 'orange', 'banana']
+ >>> fruit = set(basket) # create a set without duplicates
+ >>> fruit
+ set(['orange', 'pear', 'apple', 'banana'])
+ >>> 'orange' in fruit # fast membership testing
+ True
+ >>> 'crabgrass' in fruit
+ False
+
+ >>> # Demonstrate set operations on unique letters from two words
+ ...
+ >>> a = set('abracadabra')
+ >>> b = set('alacazam')
+ >>> a # unique letters in a
+ set(['a', 'r', 'b', 'c', 'd'])
+ >>> a - b # letters in a but not in b
+ set(['r', 'd', 'b'])
+ >>> a | b # letters in either a or b
+ set(['a', 'c', 'r', 'd', 'b', 'm', 'z', 'l'])
+ >>> a & b # letters in both a and b
+ set(['a', 'c'])
+ >>> a ^ b # letters in a or b but not both
+ set(['r', 'd', 'b', 'm', 'z', 'l'])
+
+
+.. _tut-dictionaries:
+
+Dictionaries
+============
+
+Another useful data type built into Python is the *dictionary* (see
+:ref:`typesmapping`). Dictionaries are sometimes found in other languages as
+"associative memories" or "associative arrays". Unlike sequences, which are
+indexed by a range of numbers, dictionaries are indexed by *keys*, which can be
+any immutable type; strings and numbers can always be keys. Tuples can be used
+as keys if they contain only strings, numbers, or tuples; if a tuple contains
+any mutable object either directly or indirectly, it cannot be used as a key.
+You can't use lists as keys, since lists can be modified in place using index
+assignments, slice assignments, or methods like :meth:`append` and
+:meth:`extend`.
+
+It is best to think of a dictionary as an unordered set of *key: value* pairs,
+with the requirement that the keys are unique (within one dictionary). A pair of
+braces creates an empty dictionary: ``{}``. Placing a comma-separated list of
+key:value pairs within the braces adds initial key:value pairs to the
+dictionary; this is also the way dictionaries are written on output.
+
+The main operations on a dictionary are storing a value with some key and
+extracting the value given the key. It is also possible to delete a key:value
+pair with ``del``. If you store using a key that is already in use, the old
+value associated with that key is forgotten. It is an error to extract a value
+using a non-existent key.
+
+The :meth:`keys` method of a dictionary object returns a list of all the keys
+used in the dictionary, in arbitrary order (if you want it sorted, just apply
+the :meth:`sort` method to the list of keys). To check whether a single key is
+in the dictionary, either use the dictionary's :meth:`has_key` method or the
+:keyword:`in` keyword.
+
+Here is a small example using a dictionary::
+
+ >>> tel = {'jack': 4098, 'sape': 4139}
+ >>> tel['guido'] = 4127
+ >>> tel
+ {'sape': 4139, 'guido': 4127, 'jack': 4098}
+ >>> tel['jack']
+ 4098
+ >>> del tel['sape']
+ >>> tel['irv'] = 4127
+ >>> tel
+ {'guido': 4127, 'irv': 4127, 'jack': 4098}
+ >>> tel.keys()
+ ['guido', 'irv', 'jack']
+ >>> tel.has_key('guido')
+ True
+ >>> 'guido' in tel
+ True
+
+The :func:`dict` constructor builds dictionaries directly from lists of
+key-value pairs stored as tuples. When the pairs form a pattern, list
+comprehensions can compactly specify the key-value list. ::
+
+ >>> dict([('sape', 4139), ('guido', 4127), ('jack', 4098)])
+ {'sape': 4139, 'jack': 4098, 'guido': 4127}
+ >>> dict([(x, x**2) for x in (2, 4, 6)]) # use a list comprehension
+ {2: 4, 4: 16, 6: 36}
+
+Later in the tutorial, we will learn about Generator Expressions which are even
+better suited for the task of supplying key-values pairs to the :func:`dict`
+constructor.
+
+When the keys are simple strings, it is sometimes easier to specify pairs using
+keyword arguments::
+
+ >>> dict(sape=4139, guido=4127, jack=4098)
+ {'sape': 4139, 'jack': 4098, 'guido': 4127}
+
+
+.. _tut-loopidioms:
+
+Looping Techniques
+==================
+
+When looping through dictionaries, the key and corresponding value can be
+retrieved at the same time using the :meth:`iteritems` method. ::
+
+ >>> knights = {'gallahad': 'the pure', 'robin': 'the brave'}
+ >>> for k, v in knights.iteritems():
+ ... print k, v
+ ...
+ gallahad the pure
+ robin the brave
+
+When looping through a sequence, the position index and corresponding value can
+be retrieved at the same time using the :func:`enumerate` function. ::
+
+ >>> for i, v in enumerate(['tic', 'tac', 'toe']):
+ ... print i, v
+ ...
+ 0 tic
+ 1 tac
+ 2 toe
+
+To loop over two or more sequences at the same time, the entries can be paired
+with the :func:`zip` function. ::
+
+ >>> questions = ['name', 'quest', 'favorite color']
+ >>> answers = ['lancelot', 'the holy grail', 'blue']
+ >>> for q, a in zip(questions, answers):
+ ... print 'What is your %s? It is %s.' % (q, a)
+ ...
+ What is your name? It is lancelot.
+ What is your quest? It is the holy grail.
+ What is your favorite color? It is blue.
+
+To loop over a sequence in reverse, first specify the sequence in a forward
+direction and then call the :func:`reversed` function. ::
+
+ >>> for i in reversed(range(1,10,2)):
+ ... print i
+ ...
+ 9
+ 7
+ 5
+ 3
+ 1
+
+To loop over a sequence in sorted order, use the :func:`sorted` function which
+returns a new sorted list while leaving the source unaltered. ::
+
+ >>> basket = ['apple', 'orange', 'apple', 'pear', 'orange', 'banana']
+ >>> for f in sorted(set(basket)):
+ ... print f
+ ...
+ apple
+ banana
+ orange
+ pear
+
+
+.. _tut-conditions:
+
+More on Conditions
+==================
+
+The conditions used in ``while`` and ``if`` statements can contain any
+operators, not just comparisons.
+
+The comparison operators ``in`` and ``not in`` check whether a value occurs
+(does not occur) in a sequence. The operators ``is`` and ``is not`` compare
+whether two objects are really the same object; this only matters for mutable
+objects like lists. All comparison operators have the same priority, which is
+lower than that of all numerical operators.
+
+Comparisons can be chained. For example, ``a < b == c`` tests whether ``a`` is
+less than ``b`` and moreover ``b`` equals ``c``.
+
+Comparisons may be combined using the Boolean operators ``and`` and ``or``, and
+the outcome of a comparison (or of any other Boolean expression) may be negated
+with ``not``. These have lower priorities than comparison operators; between
+them, ``not`` has the highest priority and ``or`` the lowest, so that ``A and
+not B or C`` is equivalent to ``(A and (not B)) or C``. As always, parentheses
+can be used to express the desired composition.
+
+The Boolean operators ``and`` and ``or`` are so-called *short-circuit*
+operators: their arguments are evaluated from left to right, and evaluation
+stops as soon as the outcome is determined. For example, if ``A`` and ``C`` are
+true but ``B`` is false, ``A and B and C`` does not evaluate the expression
+``C``. When used as a general value and not as a Boolean, the return value of a
+short-circuit operator is the last evaluated argument.
+
+It is possible to assign the result of a comparison or other Boolean expression
+to a variable. For example, ::
+
+ >>> string1, string2, string3 = '', 'Trondheim', 'Hammer Dance'
+ >>> non_null = string1 or string2 or string3
+ >>> non_null
+ 'Trondheim'
+
+Note that in Python, unlike C, assignment cannot occur inside expressions. C
+programmers may grumble about this, but it avoids a common class of problems
+encountered in C programs: typing ``=`` in an expression when ``==`` was
+intended.
+
+
+.. _tut-comparing:
+
+Comparing Sequences and Other Types
+===================================
+
+Sequence objects may be compared to other objects with the same sequence type.
+The comparison uses *lexicographical* ordering: first the first two items are
+compared, and if they differ this determines the outcome of the comparison; if
+they are equal, the next two items are compared, and so on, until either
+sequence is exhausted. If two items to be compared are themselves sequences of
+the same type, the lexicographical comparison is carried out recursively. If
+all items of two sequences compare equal, the sequences are considered equal.
+If one sequence is an initial sub-sequence of the other, the shorter sequence is
+the smaller (lesser) one. Lexicographical ordering for strings uses the ASCII
+ordering for individual characters. Some examples of comparisons between
+sequences of the same type::
+
+ (1, 2, 3) < (1, 2, 4)
+ [1, 2, 3] < [1, 2, 4]
+ 'ABC' < 'C' < 'Pascal' < 'Python'
+ (1, 2, 3, 4) < (1, 2, 4)
+ (1, 2) < (1, 2, -1)
+ (1, 2, 3) == (1.0, 2.0, 3.0)
+ (1, 2, ('aa', 'ab')) < (1, 2, ('abc', 'a'), 4)
+
+Note that comparing objects of different types is legal. The outcome is
+deterministic but arbitrary: the types are ordered by their name. Thus, a list
+is always smaller than a string, a string is always smaller than a tuple, etc.
+[#]_ Mixed numeric types are compared according to their numeric value, so 0
+equals 0.0, etc.
+
+
+.. rubric:: Footnotes
+
+.. [#] The rules for comparing objects of different types should not be relied upon;
+ they may change in a future version of the language.
+
diff --git a/Doc/tutorial/errors.rst b/Doc/tutorial/errors.rst
new file mode 100644
index 0000000000..99af9c7635
--- /dev/null
+++ b/Doc/tutorial/errors.rst
@@ -0,0 +1,418 @@
+.. _tut-errors:
+
+*********************
+Errors and Exceptions
+*********************
+
+Until now error messages haven't been more than mentioned, but if you have tried
+out the examples you have probably seen some. There are (at least) two
+distinguishable kinds of errors: *syntax errors* and *exceptions*.
+
+
+.. _tut-syntaxerrors:
+
+Syntax Errors
+=============
+
+Syntax errors, also known as parsing errors, are perhaps the most common kind of
+complaint you get while you are still learning Python::
+
+ >>> while True print 'Hello world'
+ File "<stdin>", line 1, in ?
+ while True print 'Hello world'
+ ^
+ SyntaxError: invalid syntax
+
+The parser repeats the offending line and displays a little 'arrow' pointing at
+the earliest point in the line where the error was detected. The error is
+caused by (or at least detected at) the token *preceding* the arrow: in the
+example, the error is detected at the keyword :keyword:`print`, since a colon
+(``':'``) is missing before it. File name and line number are printed so you
+know where to look in case the input came from a script.
+
+
+.. _tut-exceptions:
+
+Exceptions
+==========
+
+Even if a statement or expression is syntactically correct, it may cause an
+error when an attempt is made to execute it. Errors detected during execution
+are called *exceptions* and are not unconditionally fatal: you will soon learn
+how to handle them in Python programs. Most exceptions are not handled by
+programs, however, and result in error messages as shown here::
+
+ >>> 10 * (1/0)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ZeroDivisionError: integer division or modulo by zero
+ >>> 4 + spam*3
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ NameError: name 'spam' is not defined
+ >>> '2' + 2
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: cannot concatenate 'str' and 'int' objects
+
+The last line of the error message indicates what happened. Exceptions come in
+different types, and the type is printed as part of the message: the types in
+the example are :exc:`ZeroDivisionError`, :exc:`NameError` and :exc:`TypeError`.
+The string printed as the exception type is the name of the built-in exception
+that occurred. This is true for all built-in exceptions, but need not be true
+for user-defined exceptions (although it is a useful convention). Standard
+exception names are built-in identifiers (not reserved keywords).
+
+The rest of the line provides detail based on the type of exception and what
+caused it.
+
+The preceding part of the error message shows the context where the exception
+happened, in the form of a stack traceback. In general it contains a stack
+traceback listing source lines; however, it will not display lines read from
+standard input.
+
+:ref:`bltin-exceptions` lists the built-in exceptions and their meanings.
+
+
+.. _tut-handling:
+
+Handling Exceptions
+===================
+
+It is possible to write programs that handle selected exceptions. Look at the
+following example, which asks the user for input until a valid integer has been
+entered, but allows the user to interrupt the program (using :kbd:`Control-C` or
+whatever the operating system supports); note that a user-generated interruption
+is signalled by raising the :exc:`KeyboardInterrupt` exception. ::
+
+ >>> def raw_input(prompt):
+ ... import sys
+ ... sys.stdout.write(prompt)
+ ... sys.stdout.flush()
+ ... return sys.stdin.readline()
+ ...
+ >>> while True:
+ ... try:
+ ... x = int(raw_input("Please enter a number: "))
+ ... break
+ ... except ValueError:
+ ... print "Oops! That was no valid number. Try again..."
+ ...
+
+The :keyword:`try` statement works as follows.
+
+* First, the *try clause* (the statement(s) between the :keyword:`try` and
+ :keyword:`except` keywords) is executed.
+
+* If no exception occurs, the *except clause* is skipped and execution of the
+ :keyword:`try` statement is finished.
+
+* If an exception occurs during execution of the try clause, the rest of the
+ clause is skipped. Then if its type matches the exception named after the
+ :keyword:`except` keyword, the except clause is executed, and then execution
+ continues after the :keyword:`try` statement.
+
+* If an exception occurs which does not match the exception named in the except
+ clause, it is passed on to outer :keyword:`try` statements; if no handler is
+ found, it is an *unhandled exception* and execution stops with a message as
+ shown above.
+
+A :keyword:`try` statement may have more than one except clause, to specify
+handlers for different exceptions. At most one handler will be executed.
+Handlers only handle exceptions that occur in the corresponding try clause, not
+in other handlers of the same :keyword:`try` statement. An except clause may
+name multiple exceptions as a parenthesized tuple, for example::
+
+ ... except (RuntimeError, TypeError, NameError):
+ ... pass
+
+The last except clause may omit the exception name(s), to serve as a wildcard.
+Use this with extreme caution, since it is easy to mask a real programming error
+in this way! It can also be used to print an error message and then re-raise
+the exception (allowing a caller to handle the exception as well)::
+
+ import sys
+
+ try:
+ f = open('myfile.txt')
+ s = f.readline()
+ i = int(s.strip())
+ except IOError as e:
+ (errno, strerror) = e
+ print "I/O error(%s): %s" % (e.errno, e.strerror)
+ except ValueError:
+ print "Could not convert data to an integer."
+ except:
+ print "Unexpected error:", sys.exc_info()[0]
+ raise
+
+The :keyword:`try` ... :keyword:`except` statement has an optional *else
+clause*, which, when present, must follow all except clauses. It is useful for
+code that must be executed if the try clause does not raise an exception. For
+example::
+
+ for arg in sys.argv[1:]:
+ try:
+ f = open(arg, 'r')
+ except IOError:
+ print 'cannot open', arg
+ else:
+ print arg, 'has', len(f.readlines()), 'lines'
+ f.close()
+
+The use of the :keyword:`else` clause is better than adding additional code to
+the :keyword:`try` clause because it avoids accidentally catching an exception
+that wasn't raised by the code being protected by the :keyword:`try` ...
+:keyword:`except` statement.
+
+When an exception occurs, it may have an associated value, also known as the
+exception's *argument*. The presence and type of the argument depend on the
+exception type.
+
+The except clause may specify a variable after the exception name (or tuple).
+The variable is bound to an exception instance with the arguments stored in
+``instance.args``. For convenience, the exception instance defines
+:meth:`__getitem__` and :meth:`__str__` so the arguments can be accessed or
+printed directly without having to reference ``.args``.
+
+But use of ``.args`` is discouraged. Instead, the preferred use is to pass a
+single argument to an exception (which can be a tuple if multiple arguments are
+needed) and have it bound to the ``message`` attribute. One may also
+instantiate an exception first before raising it and add any attributes to it as
+desired. ::
+
+ >>> try:
+ ... raise Exception('spam', 'eggs')
+ ... except Exception as inst:
+ ... print type(inst) # the exception instance
+ ... print inst.args # arguments stored in .args
+ ... print inst # __str__ allows args to printed directly
+ ... x, y = inst # __getitem__ allows args to be unpacked directly
+ ... print 'x =', x
+ ... print 'y =', y
+ ...
+ <type 'Exception'>
+ ('spam', 'eggs')
+ ('spam', 'eggs')
+ x = spam
+ y = eggs
+
+If an exception has an argument, it is printed as the last part ('detail') of
+the message for unhandled exceptions.
+
+Exception handlers don't just handle exceptions if they occur immediately in the
+try clause, but also if they occur inside functions that are called (even
+indirectly) in the try clause. For example::
+
+ >>> def this_fails():
+ ... x = 1/0
+ ...
+ >>> try:
+ ... this_fails()
+ ... except ZeroDivisionError as detail:
+ ... print 'Handling run-time error:', detail
+ ...
+ Handling run-time error: integer division or modulo by zero
+
+
+.. _tut-raising:
+
+Raising Exceptions
+==================
+
+The :keyword:`raise` statement allows the programmer to force a specified
+exception to occur. For example::
+
+ >>> raise NameError, 'HiThere'
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ NameError: HiThere
+
+The first argument to :keyword:`raise` names the exception to be raised. The
+optional second argument specifies the exception's argument. Alternatively, the
+above could be written as ``raise NameError('HiThere')``. Either form works
+fine, but there seems to be a growing stylistic preference for the latter.
+
+If you need to determine whether an exception was raised but don't intend to
+handle it, a simpler form of the :keyword:`raise` statement allows you to
+re-raise the exception::
+
+ >>> try:
+ ... raise NameError, 'HiThere'
+ ... except NameError:
+ ... print 'An exception flew by!'
+ ... raise
+ ...
+ An exception flew by!
+ Traceback (most recent call last):
+ File "<stdin>", line 2, in ?
+ NameError: HiThere
+
+
+.. _tut-userexceptions:
+
+User-defined Exceptions
+=======================
+
+Programs may name their own exceptions by creating a new exception class.
+Exceptions should typically be derived from the :exc:`Exception` class, either
+directly or indirectly. For example::
+
+ >>> class MyError(Exception):
+ ... def __init__(self, value):
+ ... self.value = value
+ ... def __str__(self):
+ ... return repr(self.value)
+ ...
+ >>> try:
+ ... raise MyError(2*2)
+ ... except MyError as e:
+ ... print 'My exception occurred, value:', e.value
+ ...
+ My exception occurred, value: 4
+ >>> raise MyError, 'oops!'
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ __main__.MyError: 'oops!'
+
+In this example, the default :meth:`__init__` of :class:`Exception` has been
+overridden. The new behavior simply creates the *value* attribute. This
+replaces the default behavior of creating the *args* attribute.
+
+Exception classes can be defined which do anything any other class can do, but
+are usually kept simple, often only offering a number of attributes that allow
+information about the error to be extracted by handlers for the exception. When
+creating a module that can raise several distinct errors, a common practice is
+to create a base class for exceptions defined by that module, and subclass that
+to create specific exception classes for different error conditions::
+
+ class Error(Exception):
+ """Base class for exceptions in this module."""
+ pass
+
+ class InputError(Error):
+ """Exception raised for errors in the input.
+
+ Attributes:
+ expression -- input expression in which the error occurred
+ message -- explanation of the error
+ """
+
+ def __init__(self, expression, message):
+ self.expression = expression
+ self.message = message
+
+ class TransitionError(Error):
+ """Raised when an operation attempts a state transition that's not
+ allowed.
+
+ Attributes:
+ previous -- state at beginning of transition
+ next -- attempted new state
+ message -- explanation of why the specific transition is not allowed
+ """
+
+ def __init__(self, previous, next, message):
+ self.previous = previous
+ self.next = next
+ self.message = message
+
+Most exceptions are defined with names that end in "Error," similar to the
+naming of the standard exceptions.
+
+Many standard modules define their own exceptions to report errors that may
+occur in functions they define. More information on classes is presented in
+chapter :ref:`tut-classes`.
+
+
+.. _tut-cleanup:
+
+Defining Clean-up Actions
+=========================
+
+The :keyword:`try` statement has another optional clause which is intended to
+define clean-up actions that must be executed under all circumstances. For
+example::
+
+ >>> try:
+ ... raise KeyboardInterrupt
+ ... finally:
+ ... print 'Goodbye, world!'
+ ...
+ Goodbye, world!
+ Traceback (most recent call last):
+ File "<stdin>", line 2, in ?
+ KeyboardInterrupt
+
+A *finally clause* is always executed before leaving the :keyword:`try`
+statement, whether an exception has occurred or not. When an exception has
+occurred in the :keyword:`try` clause and has not been handled by an
+:keyword:`except` clause (or it has occurred in a :keyword:`except` or
+:keyword:`else` clause), it is re-raised after the :keyword:`finally` clause has
+been executed. The :keyword:`finally` clause is also executed "on the way out"
+when any other clause of the :keyword:`try` statement is left via a
+:keyword:`break`, :keyword:`continue` or :keyword:`return` statement. A more
+complicated example (having :keyword:`except` and :keyword:`finally` clauses in
+the same :keyword:`try` statement works as of Python 2.5)::
+
+ >>> def divide(x, y):
+ ... try:
+ ... result = x / y
+ ... except ZeroDivisionError:
+ ... print "division by zero!"
+ ... else:
+ ... print "result is", result
+ ... finally:
+ ... print "executing finally clause"
+ ...
+ >>> divide(2, 1)
+ result is 2
+ executing finally clause
+ >>> divide(2, 0)
+ division by zero!
+ executing finally clause
+ >>> divide("2", "1")
+ executing finally clause
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "<stdin>", line 3, in divide
+ TypeError: unsupported operand type(s) for /: 'str' and 'str'
+
+As you can see, the :keyword:`finally` clause is executed in any event. The
+:exc:`TypeError` raised by dividing two strings is not handled by the
+:keyword:`except` clause and therefore re-raised after the :keyword:`finally`
+clauses has been executed.
+
+In real world applications, the :keyword:`finally` clause is useful for
+releasing external resources (such as files or network connections), regardless
+of whether the use of the resource was successful.
+
+
+.. _tut-cleanup-with:
+
+Predefined Clean-up Actions
+===========================
+
+Some objects define standard clean-up actions to be undertaken when the object
+is no longer needed, regardless of whether or not the operation using the object
+succeeded or failed. Look at the following example, which tries to open a file
+and print its contents to the screen. ::
+
+ for line in open("myfile.txt"):
+ print line
+
+The problem with this code is that it leaves the file open for an indeterminate
+amount of time after the code has finished executing. This is not an issue in
+simple scripts, but can be a problem for larger applications. The
+:keyword:`with` statement allows objects like files to be used in a way that
+ensures they are always cleaned up promptly and correctly. ::
+
+ with open("myfile.txt") as f:
+ for line in f:
+ print line
+
+After the statement is executed, the file *f* is always closed, even if a
+problem was encountered while processing the lines. Other objects which provide
+predefined clean-up actions will indicate this in their documentation.
+
+
diff --git a/Doc/tutorial/floatingpoint.rst b/Doc/tutorial/floatingpoint.rst
new file mode 100644
index 0000000000..cbf7008ec1
--- /dev/null
+++ b/Doc/tutorial/floatingpoint.rst
@@ -0,0 +1,220 @@
+.. _tut-fp-issues:
+
+**************************************************
+Floating Point Arithmetic: Issues and Limitations
+**************************************************
+
+.. sectionauthor:: Tim Peters <tim_one@users.sourceforge.net>
+
+
+Floating-point numbers are represented in computer hardware as base 2 (binary)
+fractions. For example, the decimal fraction ::
+
+ 0.125
+
+has value 1/10 + 2/100 + 5/1000, and in the same way the binary fraction ::
+
+ 0.001
+
+has value 0/2 + 0/4 + 1/8. These two fractions have identical values, the only
+real difference being that the first is written in base 10 fractional notation,
+and the second in base 2.
+
+Unfortunately, most decimal fractions cannot be represented exactly as binary
+fractions. A consequence is that, in general, the decimal floating-point
+numbers you enter are only approximated by the binary floating-point numbers
+actually stored in the machine.
+
+The problem is easier to understand at first in base 10. Consider the fraction
+1/3. You can approximate that as a base 10 fraction::
+
+ 0.3
+
+or, better, ::
+
+ 0.33
+
+or, better, ::
+
+ 0.333
+
+and so on. No matter how many digits you're willing to write down, the result
+will never be exactly 1/3, but will be an increasingly better approximation of
+1/3.
+
+In the same way, no matter how many base 2 digits you're willing to use, the
+decimal value 0.1 cannot be represented exactly as a base 2 fraction. In base
+2, 1/10 is the infinitely repeating fraction ::
+
+ 0.0001100110011001100110011001100110011001100110011...
+
+Stop at any finite number of bits, and you get an approximation. This is why
+you see things like::
+
+ >>> 0.1
+ 0.10000000000000001
+
+On most machines today, that is what you'll see if you enter 0.1 at a Python
+prompt. You may not, though, because the number of bits used by the hardware to
+store floating-point values can vary across machines, and Python only prints a
+decimal approximation to the true decimal value of the binary approximation
+stored by the machine. On most machines, if Python were to print the true
+decimal value of the binary approximation stored for 0.1, it would have to
+display ::
+
+ >>> 0.1
+ 0.1000000000000000055511151231257827021181583404541015625
+
+instead! The Python prompt uses the builtin :func:`repr` function to obtain a
+string version of everything it displays. For floats, ``repr(float)`` rounds
+the true decimal value to 17 significant digits, giving ::
+
+ 0.10000000000000001
+
+``repr(float)`` produces 17 significant digits because it turns out that's
+enough (on most machines) so that ``eval(repr(x)) == x`` exactly for all finite
+floats *x*, but rounding to 16 digits is not enough to make that true.
+
+Note that this is in the very nature of binary floating-point: this is not a bug
+in Python, and it is not a bug in your code either. You'll see the same kind of
+thing in all languages that support your hardware's floating-point arithmetic
+(although some languages may not *display* the difference by default, or in all
+output modes).
+
+Python's builtin :func:`str` function produces only 12 significant digits, and
+you may wish to use that instead. It's unusual for ``eval(str(x))`` to
+reproduce *x*, but the output may be more pleasant to look at::
+
+ >>> print str(0.1)
+ 0.1
+
+It's important to realize that this is, in a real sense, an illusion: the value
+in the machine is not exactly 1/10, you're simply rounding the *display* of the
+true machine value.
+
+Other surprises follow from this one. For example, after seeing ::
+
+ >>> 0.1
+ 0.10000000000000001
+
+you may be tempted to use the :func:`round` function to chop it back to the
+single digit you expect. But that makes no difference::
+
+ >>> round(0.1, 1)
+ 0.10000000000000001
+
+The problem is that the binary floating-point value stored for "0.1" was already
+the best possible binary approximation to 1/10, so trying to round it again
+can't make it better: it was already as good as it gets.
+
+Another consequence is that since 0.1 is not exactly 1/10, summing ten values of
+0.1 may not yield exactly 1.0, either::
+
+ >>> sum = 0.0
+ >>> for i in range(10):
+ ... sum += 0.1
+ ...
+ >>> sum
+ 0.99999999999999989
+
+Binary floating-point arithmetic holds many surprises like this. The problem
+with "0.1" is explained in precise detail below, in the "Representation Error"
+section. See `The Perils of Floating Point <http://www.lahey.com/float.htm>`_
+for a more complete account of other common surprises.
+
+As that says near the end, "there are no easy answers." Still, don't be unduly
+wary of floating-point! The errors in Python float operations are inherited
+from the floating-point hardware, and on most machines are on the order of no
+more than 1 part in 2\*\*53 per operation. That's more than adequate for most
+tasks, but you do need to keep in mind that it's not decimal arithmetic, and
+that every float operation can suffer a new rounding error.
+
+While pathological cases do exist, for most casual use of floating-point
+arithmetic you'll see the result you expect in the end if you simply round the
+display of your final results to the number of decimal digits you expect.
+:func:`str` usually suffices, and for finer control see the discussion of
+Python's ``%`` format operator: the ``%g``, ``%f`` and ``%e`` format codes
+supply flexible and easy ways to round float results for display.
+
+
+.. _tut-fp-error:
+
+Representation Error
+====================
+
+This section explains the "0.1" example in detail, and shows how you can perform
+an exact analysis of cases like this yourself. Basic familiarity with binary
+floating-point representation is assumed.
+
+:dfn:`Representation error` refers to the fact that some (most, actually)
+decimal fractions cannot be represented exactly as binary (base 2) fractions.
+This is the chief reason why Python (or Perl, C, C++, Java, Fortran, and many
+others) often won't display the exact decimal number you expect::
+
+ >>> 0.1
+ 0.10000000000000001
+
+Why is that? 1/10 is not exactly representable as a binary fraction. Almost all
+machines today (November 2000) use IEEE-754 floating point arithmetic, and
+almost all platforms map Python floats to IEEE-754 "double precision". 754
+doubles contain 53 bits of precision, so on input the computer strives to
+convert 0.1 to the closest fraction it can of the form *J*/2\*\**N* where *J* is
+an integer containing exactly 53 bits. Rewriting ::
+
+ 1 / 10 ~= J / (2**N)
+
+as ::
+
+ J ~= 2**N / 10
+
+and recalling that *J* has exactly 53 bits (is ``>= 2**52`` but ``< 2**53``),
+the best value for *N* is 56::
+
+ >>> 2**52
+ 4503599627370496L
+ >>> 2**53
+ 9007199254740992L
+ >>> 2**56/10
+ 7205759403792793L
+
+That is, 56 is the only value for *N* that leaves *J* with exactly 53 bits. The
+best possible value for *J* is then that quotient rounded::
+
+ >>> q, r = divmod(2**56, 10)
+ >>> r
+ 6L
+
+Since the remainder is more than half of 10, the best approximation is obtained
+by rounding up::
+
+ >>> q+1
+ 7205759403792794L
+
+Therefore the best possible approximation to 1/10 in 754 double precision is
+that over 2\*\*56, or ::
+
+ 7205759403792794 / 72057594037927936
+
+Note that since we rounded up, this is actually a little bit larger than 1/10;
+if we had not rounded up, the quotient would have been a little bit smaller than
+1/10. But in no case can it be *exactly* 1/10!
+
+So the computer never "sees" 1/10: what it sees is the exact fraction given
+above, the best 754 double approximation it can get::
+
+ >>> .1 * 2**56
+ 7205759403792794.0
+
+If we multiply that fraction by 10\*\*30, we can see the (truncated) value of
+its 30 most significant decimal digits::
+
+ >>> 7205759403792794 * 10**30 / 2**56
+ 100000000000000005551115123125L
+
+meaning that the exact number stored in the computer is approximately equal to
+the decimal value 0.100000000000000005551115123125. Rounding that to 17
+significant digits gives the 0.10000000000000001 that Python displays (well,
+will display on any 754-conforming platform that does best-possible input and
+output conversions in its C library --- yours may not!).
+
+
diff --git a/Doc/tutorial/glossary.rst b/Doc/tutorial/glossary.rst
new file mode 100644
index 0000000000..c05d68d5f2
--- /dev/null
+++ b/Doc/tutorial/glossary.rst
@@ -0,0 +1,329 @@
+
+.. _tut-glossary:
+
+********
+Glossary
+********
+
+.. % %% keep the entries sorted and include at least one \index{} item for each
+.. % %% cross-references are marked with \emph{entry}
+
+``>>>``
+ The typical Python prompt of the interactive shell. Often seen for code
+ examples that can be tried right away in the interpreter.
+
+ .. index:: single: ...
+
+``...``
+ The typical Python prompt of the interactive shell when entering code for an
+ indented code block.
+
+ .. index:: single: BDFL
+
+BDFL
+ Benevolent Dictator For Life, a.k.a. `Guido van Rossum
+ <http://www.python.org/~guido/>`_, Python's creator.
+
+ .. index:: single: byte code
+
+byte code
+ The internal representation of a Python program in the interpreter. The byte
+ code is also cached in ``.pyc`` and ``.pyo`` files so that executing the same
+ file is faster the second time (recompilation from source to byte code can be
+ avoided). This "intermediate language" is said to run on a "virtual machine"
+ that calls the subroutines corresponding to each bytecode.
+
+ .. index:: single: classic class
+
+classic class
+ Any class which does not inherit from :class:`object`. See *new-style class*.
+
+ .. index:: single: complex number
+
+complex number
+ An extension of the familiar real number system in which all numbers are
+ expressed as a sum of a real part and an imaginary part. Imaginary numbers are
+ real multiples of the imaginary unit (the square root of ``-1``), often written
+ ``i`` in mathematics or ``j`` in engineering. Python has builtin support for
+ complex numbers, which are written with this latter notation; the imaginary part
+ is written with a ``j`` suffix, e.g., ``3+1j``. To get access to complex
+ equivalents of the :mod:`math` module, use :mod:`cmath`. Use of complex numbers
+ is a fairly advanced mathematical feature. If you're not aware of a need for
+ them, it's almost certain you can safely ignore them.
+
+ .. index:: single: descriptor
+
+descriptor
+ Any *new-style* object that defines the methods :meth:`__get__`,
+ :meth:`__set__`, or :meth:`__delete__`. When a class attribute is a descriptor,
+ its special binding behavior is triggered upon attribute lookup. Normally,
+ writing *a.b* looks up the object *b* in the class dictionary for *a*, but if
+ *b* is a descriptor, the defined method gets called. Understanding descriptors
+ is a key to a deep understanding of Python because they are the basis for many
+ features including functions, methods, properties, class methods, static
+ methods, and reference to super classes.
+
+ .. index:: single: dictionary
+
+dictionary
+ An associative array, where arbitrary keys are mapped to values. The use of
+ :class:`dict` much resembles that for :class:`list`, but the keys can be any
+ object with a :meth:`__hash__` function, not just integers starting from zero.
+ Called a hash in Perl.
+
+ .. index:: single: duck-typing
+
+duck-typing
+ Pythonic programming style that determines an object's type by inspection of its
+ method or attribute signature rather than by explicit relationship to some type
+ object ("If it looks like a duck and quacks like a duck, it must be a duck.")
+ By emphasizing interfaces rather than specific types, well-designed code
+ improves its flexibility by allowing polymorphic substitution. Duck-typing
+ avoids tests using :func:`type` or :func:`isinstance`. Instead, it typically
+ employs :func:`hasattr` tests or *EAFP* programming.
+
+ .. index:: single: EAFP
+
+EAFP
+ Easier to ask for forgiveness than permission. This common Python coding style
+ assumes the existence of valid keys or attributes and catches exceptions if the
+ assumption proves false. This clean and fast style is characterized by the
+ presence of many :keyword:`try` and :keyword:`except` statements. The technique
+ contrasts with the *LBYL* style that is common in many other languages such as
+ C.
+
+ .. index:: single: __future__
+
+__future__
+ A pseudo module which programmers can use to enable new language features which
+ are not compatible with the current interpreter. To enable ``new_feature`` ::
+
+ from __future__ import new_feature
+
+ By importing the :mod:`__future__` module and evaluating its variables, you
+ can see when a new feature was first added to the language and when it will
+ become the default::
+
+ >>> import __future__
+ >>> __future__.division
+ _Feature((2, 2, 0, 'alpha', 2), (3, 0, 0, 'alpha', 0), 8192)
+
+ .. index:: single: generator
+
+generator
+ A function that returns an iterator. It looks like a normal function except
+ that values are returned to the caller using a :keyword:`yield` statement
+ instead of a :keyword:`return` statement. Generator functions often contain one
+ or more :keyword:`for` or :keyword:`while` loops that :keyword:`yield` elements
+ back to the caller. The function execution is stopped at the :keyword:`yield`
+ keyword (returning the result) and is resumed there when the next element is
+ requested by calling the :meth:`__next__` method of the returned iterator.
+
+ .. index:: single: generator expression
+
+generator expression
+ An expression that returns a generator. It looks like a normal expression
+ followed by a :keyword:`for` expression defining a loop variable, range, and an
+ optional :keyword:`if` expression. The combined expression generates values for
+ an enclosing function::
+
+ >>> sum(i*i for i in range(10)) # sum of squares 0, 1, 4, ... 81
+ 285
+
+ .. index:: single: GIL
+
+GIL
+ See *global interpreter lock*.
+
+ .. index:: single: global interpreter lock
+
+global interpreter lock
+ The lock used by Python threads to assure that only one thread can be run at
+ a time. This simplifies Python by assuring that no two processes can access
+ the same memory at the same time. Locking the entire interpreter makes it
+ easier for the interpreter to be multi-threaded, at the expense of some
+ parallelism on multi-processor machines. Efforts have been made in the past
+ to create a "free-threaded" interpreter (one which locks shared data at a
+ much finer granularity), but performance suffered in the common
+ single-processor case.
+
+ .. index:: single: IDLE
+
+IDLE
+ An Integrated Development Environment for Python. IDLE is a basic editor and
+ interpreter environment that ships with the standard distribution of Python.
+ Good for beginners, it also serves as clear example code for those wanting to
+ implement a moderately sophisticated, multi-platform GUI application.
+
+ .. index:: single: immutable
+
+immutable
+ An object with fixed value. Immutable objects are numbers, strings or tuples
+ (and more). Such an object cannot be altered. A new object has to be created
+ if a different value has to be stored. They play an important role in places
+ where a constant hash value is needed, for example as a key in a dictionary.
+
+ .. index:: single: integer division
+
+integer division
+ Mathematical division including any remainder. The result will always be a
+ float. For example, the expression ``11/4`` evaluates to ``2.75``. Integer
+ division can be forced by using the ``//`` operator instead of the ``/``
+ operator.
+
+ .. index:: single: interactive
+
+interactive
+ Python has an interactive interpreter which means that you can try out things
+ and immediately see their results. Just launch ``python`` with no arguments
+ (possibly by selecting it from your computer's main menu). It is a very powerful
+ way to test out new ideas or inspect modules and packages (remember
+ ``help(x)``).
+
+ .. index:: single: interpreted
+
+interpreted
+ Python is an interpreted language, as opposed to a compiled one. This means
+ that the source files can be run directly without first creating an executable
+ which is then run. Interpreted languages typically have a shorter
+ development/debug cycle than compiled ones, though their programs generally also
+ run more slowly. See also *interactive*.
+
+ .. index:: single: iterable
+
+iterable
+ A container object capable of returning its members one at a time. Examples of
+ iterables include all sequence types (such as :class:`list`, :class:`str`, and
+ :class:`tuple`) and some non-sequence types like :class:`dict` and :class:`file`
+ and objects of any classes you define with an :meth:`__iter__` or
+ :meth:`__getitem__` method. Iterables can be used in a :keyword:`for` loop and
+ in many other places where a sequence is needed (:func:`zip`, :func:`map`, ...).
+ When an iterable object is passed as an argument to the builtin function
+ :func:`iter`, it returns an iterator for the object. This iterator is good for
+ one pass over the set of values. When using iterables, it is usually not
+ necessary to call :func:`iter` or deal with iterator objects yourself. The
+ ``for`` statement does that automatically for you, creating a temporary unnamed
+ variable to hold the iterator for the duration of the loop. See also
+ *iterator*, *sequence*, and *generator*.
+
+ .. index:: single: iterator
+
+iterator
+ An object representing a stream of data. Repeated calls to the iterator's
+ :meth:`__next__` method return successive items in the stream. When no more
+ data is available a :exc:`StopIteration` exception is raised instead. At this
+ point, the iterator object is exhausted and any further calls to its
+ :meth:`__next__` method just raise :exc:`StopIteration` again. Iterators are
+ required to have an :meth:`__iter__` method that returns the iterator object
+ itself so every iterator is also iterable and may be used in most places where
+ other iterables are accepted. One notable exception is code that attempts
+ multiple iteration passes. A container object (such as a :class:`list`)
+ produces a fresh new iterator each time you pass it to the :func:`iter` function
+ or use it in a :keyword:`for` loop. Attempting this with an iterator will just
+ return the same exhausted iterator object used in the previous iteration pass,
+ making it appear like an empty container.
+
+ .. index:: single: LBYL
+
+LBYL
+ Look before you leap. This coding style explicitly tests for pre-conditions
+ before making calls or lookups. This style contrasts with the *EAFP* approach
+ and is characterized by the presence of many :keyword:`if` statements.
+
+ .. index:: single: list comprehension
+
+list comprehension
+ A compact way to process all or a subset of elements in a sequence and return a
+ list with the results. ``result = ["0x%02x" % x for x in range(256) if x % 2 ==
+ 0]`` generates a list of strings containing hex numbers (0x..) that are even and
+ in the range from 0 to 255. The :keyword:`if` clause is optional. If omitted,
+ all elements in ``range(256)`` are processed.
+
+ .. index:: single: mapping
+
+mapping
+ A container object (such as :class:`dict`) that supports arbitrary key lookups
+ using the special method :meth:`__getitem__`.
+
+ .. index:: single: metaclass
+
+metaclass
+ The class of a class. Class definitions create a class name, a class
+ dictionary, and a list of base classes. The metaclass is responsible for taking
+ those three arguments and creating the class. Most object oriented programming
+ languages provide a default implementation. What makes Python special is that
+ it is possible to create custom metaclasses. Most users never need this tool,
+ but when the need arises, metaclasses can provide powerful, elegant solutions.
+ They have been used for logging attribute access, adding thread-safety, tracking
+ object creation, implementing singletons, and many other tasks.
+
+ .. index:: single: mutable
+
+mutable
+ Mutable objects can change their value but keep their :func:`id`. See also
+ *immutable*.
+
+ .. index:: single: namespace
+
+namespace
+ The place where a variable is stored. Namespaces are implemented as
+ dictionaries. There are the local, global and builtin namespaces as well as
+ nested namespaces in objects (in methods). Namespaces support modularity by
+ preventing naming conflicts. For instance, the functions
+ :func:`__builtin__.open` and :func:`os.open` are distinguished by their
+ namespaces. Namespaces also aid readability and maintainability by making it
+ clear which module implements a function. For instance, writing
+ :func:`random.seed` or :func:`itertools.izip` makes it clear that those
+ functions are implemented by the :mod:`random` and :mod:`itertools` modules
+ respectively.
+
+ .. index:: single: nested scope
+
+nested scope
+ The ability to refer to a variable in an enclosing definition. For instance, a
+ function defined inside another function can refer to variables in the outer
+ function. Note that nested scopes work only for reference and not for
+ assignment which will always write to the innermost scope. In contrast, local
+ variables both read and write in the innermost scope. Likewise, global
+ variables read and write to the global namespace.
+
+ .. index:: single: new-style class
+
+new-style class
+ Any class that inherits from :class:`object`. This includes all built-in types
+ like :class:`list` and :class:`dict`. Only new-style classes can use Python's
+ newer, versatile features like :meth:`__slots__`, descriptors, properties,
+ :meth:`__getattribute__`, class methods, and static methods.
+
+ .. index:: single: Python3000
+
+Python3000
+ A mythical python release, not required to be backward compatible, with
+ telepathic interface.
+
+ .. index:: single: __slots__
+
+__slots__
+ A declaration inside a *new-style class* that saves memory by pre-declaring
+ space for instance attributes and eliminating instance dictionaries. Though
+ popular, the technique is somewhat tricky to get right and is best reserved for
+ rare cases where there are large numbers of instances in a memory-critical
+ application.
+
+ .. index:: single: sequence
+
+sequence
+ An *iterable* which supports efficient element access using integer indices via
+ the :meth:`__getitem__` and :meth:`__len__` special methods. Some built-in
+ sequence types are :class:`list`, :class:`str`, :class:`tuple`, and
+ :class:`unicode`. Note that :class:`dict` also supports :meth:`__getitem__` and
+ :meth:`__len__`, but is considered a mapping rather than a sequence because the
+ lookups use arbitrary *immutable* keys rather than integers.
+
+ .. index:: single: Zen of Python
+
+Zen of Python
+ Listing of Python design principles and philosophies that are helpful in
+ understanding and using the language. The listing can be found by typing
+ "``import this``" at the interactive prompt.
+
diff --git a/Doc/tutorial/index.rst b/Doc/tutorial/index.rst
new file mode 100644
index 0000000000..7309b7c7aa
--- /dev/null
+++ b/Doc/tutorial/index.rst
@@ -0,0 +1,60 @@
+.. _tutorial-index:
+
+######################
+ The Python tutorial
+######################
+
+:Release: |version|
+:Date: |today|
+
+Python is an easy to learn, powerful programming language. It has efficient
+high-level data structures and a simple but effective approach to
+object-oriented programming. Python's elegant syntax and dynamic typing,
+together with its interpreted nature, make it an ideal language for scripting
+and rapid application development in many areas on most platforms.
+
+The Python interpreter and the extensive standard library are freely available
+in source or binary form for all major platforms from the Python Web site,
+http://www.python.org/, and may be freely distributed. The same site also
+contains distributions of and pointers to many free third party Python modules,
+programs and tools, and additional documentation.
+
+The Python interpreter is easily extended with new functions and data types
+implemented in C or C++ (or other languages callable from C). Python is also
+suitable as an extension language for customizable applications.
+
+This tutorial introduces the reader informally to the basic concepts and
+features of the Python language and system. It helps to have a Python
+interpreter handy for hands-on experience, but all examples are self-contained,
+so the tutorial can be read off-line as well.
+
+For a description of standard objects and modules, see the Python Library
+Reference document. The Python Reference Manual gives a more formal definition
+of the language. To write extensions in C or C++, read Extending and Embedding
+the Python Interpreter and Python/C API Reference. There are also several books
+covering Python in depth.
+
+This tutorial does not attempt to be comprehensive and cover every single
+feature, or even every commonly used feature. Instead, it introduces many of
+Python's most noteworthy features, and will give you a good idea of the
+language's flavor and style. After reading it, you will be able to read and
+write Python modules and programs, and you will be ready to learn more about the
+various Python library modules described in the Python Library Reference.
+
+.. toctree::
+
+ appetite.rst
+ interpreter.rst
+ introduction.rst
+ controlflow.rst
+ datastructures.rst
+ modules.rst
+ inputoutput.rst
+ errors.rst
+ classes.rst
+ stdlib.rst
+ stdlib2.rst
+ whatnow.rst
+ interactive.rst
+ floatingpoint.rst
+ glossary.rst
diff --git a/Doc/tutorial/inputoutput.rst b/Doc/tutorial/inputoutput.rst
new file mode 100644
index 0000000000..9c302affe6
--- /dev/null
+++ b/Doc/tutorial/inputoutput.rst
@@ -0,0 +1,354 @@
+.. _tut-io:
+
+****************
+Input and Output
+****************
+
+There are several ways to present the output of a program; data can be printed
+in a human-readable form, or written to a file for future use. This chapter will
+discuss some of the possibilities.
+
+
+.. _tut-formatting:
+
+Fancier Output Formatting
+=========================
+
+So far we've encountered two ways of writing values: *expression statements* and
+the :keyword:`print` statement. (A third way is using the :meth:`write` method
+of file objects; the standard output file can be referenced as ``sys.stdout``.
+See the Library Reference for more information on this.)
+
+.. index:: module: string
+
+Often you'll want more control over the formatting of your output than simply
+printing space-separated values. There are two ways to format your output; the
+first way is to do all the string handling yourself; using string slicing and
+concatenation operations you can create any layout you can imagine. The
+standard module :mod:`string` contains some useful operations for padding
+strings to a given column width; these will be discussed shortly. The second
+way is to use the ``%`` operator with a string as the left argument. The ``%``
+operator interprets the left argument much like a :cfunc:`sprintf`\ -style
+format string to be applied to the right argument, and returns the string
+resulting from this formatting operation.
+
+One question remains, of course: how do you convert values to strings? Luckily,
+Python has ways to convert any value to a string: pass it to the :func:`repr`
+or :func:`str` functions. Reverse quotes (``````) are equivalent to
+:func:`repr`, but they are no longer used in modern Python code and will likely
+not be in future versions of the language.
+
+The :func:`str` function is meant to return representations of values which are
+fairly human-readable, while :func:`repr` is meant to generate representations
+which can be read by the interpreter (or will force a :exc:`SyntaxError` if
+there is not equivalent syntax). For objects which don't have a particular
+representation for human consumption, :func:`str` will return the same value as
+:func:`repr`. Many values, such as numbers or structures like lists and
+dictionaries, have the same representation using either function. Strings and
+floating point numbers, in particular, have two distinct representations.
+
+Some examples::
+
+ >>> s = 'Hello, world.'
+ >>> str(s)
+ 'Hello, world.'
+ >>> repr(s)
+ "'Hello, world.'"
+ >>> str(0.1)
+ '0.1'
+ >>> repr(0.1)
+ '0.10000000000000001'
+ >>> x = 10 * 3.25
+ >>> y = 200 * 200
+ >>> s = 'The value of x is ' + repr(x) + ', and y is ' + repr(y) + '...'
+ >>> print s
+ The value of x is 32.5, and y is 40000...
+ >>> # The repr() of a string adds string quotes and backslashes:
+ ... hello = 'hello, world\n'
+ >>> hellos = repr(hello)
+ >>> print hellos
+ 'hello, world\n'
+ >>> # The argument to repr() may be any Python object:
+ ... repr((x, y, ('spam', 'eggs')))
+ "(32.5, 40000, ('spam', 'eggs'))"
+ >>> # reverse quotes are convenient in interactive sessions:
+ ... `x, y, ('spam', 'eggs')`
+ "(32.5, 40000, ('spam', 'eggs'))"
+
+Here are two ways to write a table of squares and cubes::
+
+ >>> for x in range(1, 11):
+ ... print repr(x).rjust(2), repr(x*x).rjust(3),
+ ... # Note trailing comma on previous line
+ ... print repr(x*x*x).rjust(4)
+ ...
+ 1 1 1
+ 2 4 8
+ 3 9 27
+ 4 16 64
+ 5 25 125
+ 6 36 216
+ 7 49 343
+ 8 64 512
+ 9 81 729
+ 10 100 1000
+
+ >>> for x in range(1,11):
+ ... print '%2d %3d %4d' % (x, x*x, x*x*x)
+ ...
+ 1 1 1
+ 2 4 8
+ 3 9 27
+ 4 16 64
+ 5 25 125
+ 6 36 216
+ 7 49 343
+ 8 64 512
+ 9 81 729
+ 10 100 1000
+
+(Note that in the first example, one space between each column was added by the
+way :keyword:`print` works: it always adds spaces between its arguments.)
+
+This example demonstrates the :meth:`rjust` method of string objects, which
+right-justifies a string in a field of a given width by padding it with spaces
+on the left. There are similar methods :meth:`ljust` and :meth:`center`. These
+methods do not write anything, they just return a new string. If the input
+string is too long, they don't truncate it, but return it unchanged; this will
+mess up your column lay-out but that's usually better than the alternative,
+which would be lying about a value. (If you really want truncation you can
+always add a slice operation, as in ``x.ljust(n)[:n]``.)
+
+There is another method, :meth:`zfill`, which pads a numeric string on the left
+with zeros. It understands about plus and minus signs::
+
+ >>> '12'.zfill(5)
+ '00012'
+ >>> '-3.14'.zfill(7)
+ '-003.14'
+ >>> '3.14159265359'.zfill(5)
+ '3.14159265359'
+
+Using the ``%`` operator looks like this::
+
+ >>> import math
+ >>> print 'The value of PI is approximately %5.3f.' % math.pi
+ The value of PI is approximately 3.142.
+
+If there is more than one format in the string, you need to pass a tuple as
+right operand, as in this example::
+
+ >>> table = {'Sjoerd': 4127, 'Jack': 4098, 'Dcab': 7678}
+ >>> for name, phone in table.items():
+ ... print '%-10s ==> %10d' % (name, phone)
+ ...
+ Jack ==> 4098
+ Dcab ==> 7678
+ Sjoerd ==> 4127
+
+Most formats work exactly as in C and require that you pass the proper type;
+however, if you don't you get an exception, not a core dump. The ``%s`` format
+is more relaxed: if the corresponding argument is not a string object, it is
+converted to string using the :func:`str` built-in function. Using ``*`` to
+pass the width or precision in as a separate (integer) argument is supported.
+The C formats ``%n`` and ``%p`` are not supported.
+
+If you have a really long format string that you don't want to split up, it
+would be nice if you could reference the variables to be formatted by name
+instead of by position. This can be done by using form ``%(name)format``, as
+shown here::
+
+ >>> table = {'Sjoerd': 4127, 'Jack': 4098, 'Dcab': 8637678}
+ >>> print 'Jack: %(Jack)d; Sjoerd: %(Sjoerd)d; Dcab: %(Dcab)d' % table
+ Jack: 4098; Sjoerd: 4127; Dcab: 8637678
+
+This is particularly useful in combination with the new built-in :func:`vars`
+function, which returns a dictionary containing all local variables.
+
+
+.. _tut-files:
+
+Reading and Writing Files
+=========================
+
+.. index::
+ builtin: open
+ object: file
+
+:func:`open` returns a file object, and is most commonly used with two
+arguments: ``open(filename, mode)``.
+
+.. % Opening files
+
+::
+
+ >>> f=open('/tmp/workfile', 'w')
+ >>> print f
+ <open file '/tmp/workfile', mode 'w' at 80a0960>
+
+The first argument is a string containing the filename. The second argument is
+another string containing a few characters describing the way in which the file
+will be used. *mode* can be ``'r'`` when the file will only be read, ``'w'``
+for only writing (an existing file with the same name will be erased), and
+``'a'`` opens the file for appending; any data written to the file is
+automatically added to the end. ``'r+'`` opens the file for both reading and
+writing. The *mode* argument is optional; ``'r'`` will be assumed if it's
+omitted.
+
+On Windows and the Macintosh, ``'b'`` appended to the mode opens the file in
+binary mode, so there are also modes like ``'rb'``, ``'wb'``, and ``'r+b'``.
+Windows makes a distinction between text and binary files; the end-of-line
+characters in text files are automatically altered slightly when data is read or
+written. This behind-the-scenes modification to file data is fine for ASCII
+text files, but it'll corrupt binary data like that in :file:`JPEG` or
+:file:`EXE` files. Be very careful to use binary mode when reading and writing
+such files.
+
+
+.. _tut-filemethods:
+
+Methods of File Objects
+-----------------------
+
+The rest of the examples in this section will assume that a file object called
+``f`` has already been created.
+
+To read a file's contents, call ``f.read(size)``, which reads some quantity of
+data and returns it as a string. *size* is an optional numeric argument. When
+*size* is omitted or negative, the entire contents of the file will be read and
+returned; it's your problem if the file is twice as large as your machine's
+memory. Otherwise, at most *size* bytes are read and returned. If the end of
+the file has been reached, ``f.read()`` will return an empty string (``""``).
+::
+
+ >>> f.read()
+ 'This is the entire file.\n'
+ >>> f.read()
+ ''
+
+``f.readline()`` reads a single line from the file; a newline character (``\n``)
+is left at the end of the string, and is only omitted on the last line of the
+file if the file doesn't end in a newline. This makes the return value
+unambiguous; if ``f.readline()`` returns an empty string, the end of the file
+has been reached, while a blank line is represented by ``'\n'``, a string
+containing only a single newline. ::
+
+ >>> f.readline()
+ 'This is the first line of the file.\n'
+ >>> f.readline()
+ 'Second line of the file\n'
+ >>> f.readline()
+ ''
+
+``f.readlines()`` returns a list containing all the lines of data in the file.
+If given an optional parameter *sizehint*, it reads that many bytes from the
+file and enough more to complete a line, and returns the lines from that. This
+is often used to allow efficient reading of a large file by lines, but without
+having to load the entire file in memory. Only complete lines will be returned.
+::
+
+ >>> f.readlines()
+ ['This is the first line of the file.\n', 'Second line of the file\n']
+
+An alternate approach to reading lines is to loop over the file object. This is
+memory efficient, fast, and leads to simpler code::
+
+ >>> for line in f:
+ print line,
+
+ This is the first line of the file.
+ Second line of the file
+
+The alternative approach is simpler but does not provide as fine-grained
+control. Since the two approaches manage line buffering differently, they
+should not be mixed.
+
+``f.write(string)`` writes the contents of *string* to the file, returning
+``None``. ::
+
+ >>> f.write('This is a test\n')
+
+To write something other than a string, it needs to be converted to a string
+first::
+
+ >>> value = ('the answer', 42)
+ >>> s = str(value)
+ >>> f.write(s)
+
+``f.tell()`` returns an integer giving the file object's current position in the
+file, measured in bytes from the beginning of the file. To change the file
+object's position, use ``f.seek(offset, from_what)``. The position is computed
+from adding *offset* to a reference point; the reference point is selected by
+the *from_what* argument. A *from_what* value of 0 measures from the beginning
+of the file, 1 uses the current file position, and 2 uses the end of the file as
+the reference point. *from_what* can be omitted and defaults to 0, using the
+beginning of the file as the reference point. ::
+
+ >>> f = open('/tmp/workfile', 'r+')
+ >>> f.write('0123456789abcdef')
+ >>> f.seek(5) # Go to the 6th byte in the file
+ >>> f.read(1)
+ '5'
+ >>> f.seek(-3, 2) # Go to the 3rd byte before the end
+ >>> f.read(1)
+ 'd'
+
+When you're done with a file, call ``f.close()`` to close it and free up any
+system resources taken up by the open file. After calling ``f.close()``,
+attempts to use the file object will automatically fail. ::
+
+ >>> f.close()
+ >>> f.read()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: I/O operation on closed file
+
+File objects have some additional methods, such as :meth:`isatty` and
+:meth:`truncate` which are less frequently used; consult the Library Reference
+for a complete guide to file objects.
+
+
+.. _tut-pickle:
+
+The :mod:`pickle` Module
+------------------------
+
+.. index:: module: pickle
+
+Strings can easily be written to and read from a file. Numbers take a bit more
+effort, since the :meth:`read` method only returns strings, which will have to
+be passed to a function like :func:`int`, which takes a string like ``'123'``
+and returns its numeric value 123. However, when you want to save more complex
+data types like lists, dictionaries, or class instances, things get a lot more
+complicated.
+
+Rather than have users be constantly writing and debugging code to save
+complicated data types, Python provides a standard module called :mod:`pickle`.
+This is an amazing module that can take almost any Python object (even some
+forms of Python code!), and convert it to a string representation; this process
+is called :dfn:`pickling`. Reconstructing the object from the string
+representation is called :dfn:`unpickling`. Between pickling and unpickling,
+the string representing the object may have been stored in a file or data, or
+sent over a network connection to some distant machine.
+
+If you have an object ``x``, and a file object ``f`` that's been opened for
+writing, the simplest way to pickle the object takes only one line of code::
+
+ pickle.dump(x, f)
+
+To unpickle the object again, if ``f`` is a file object which has been opened
+for reading::
+
+ x = pickle.load(f)
+
+(There are other variants of this, used when pickling many objects or when you
+don't want to write the pickled data to a file; consult the complete
+documentation for :mod:`pickle` in the Python Library Reference.)
+
+:mod:`pickle` is the standard way to make Python objects which can be stored and
+reused by other programs or by a future invocation of the same program; the
+technical term for this is a :dfn:`persistent` object. Because :mod:`pickle` is
+so widely used, many authors who write Python extensions take care to ensure
+that new data types such as matrices can be properly pickled and unpickled.
+
+
diff --git a/Doc/tutorial/interactive.rst b/Doc/tutorial/interactive.rst
new file mode 100644
index 0000000000..8eeca2a47c
--- /dev/null
+++ b/Doc/tutorial/interactive.rst
@@ -0,0 +1,167 @@
+.. _tut-interacting:
+
+**************************************************
+Interactive Input Editing and History Substitution
+**************************************************
+
+Some versions of the Python interpreter support editing of the current input
+line and history substitution, similar to facilities found in the Korn shell and
+the GNU Bash shell. This is implemented using the *GNU Readline* library, which
+supports Emacs-style and vi-style editing. This library has its own
+documentation which I won't duplicate here; however, the basics are easily
+explained. The interactive editing and history described here are optionally
+available in the Unix and Cygwin versions of the interpreter.
+
+This chapter does *not* document the editing facilities of Mark Hammond's
+PythonWin package or the Tk-based environment, IDLE, distributed with Python.
+The command line history recall which operates within DOS boxes on NT and some
+other DOS and Windows flavors is yet another beast.
+
+
+.. _tut-lineediting:
+
+Line Editing
+============
+
+If supported, input line editing is active whenever the interpreter prints a
+primary or secondary prompt. The current line can be edited using the
+conventional Emacs control characters. The most important of these are:
+:kbd:`C-A` (Control-A) moves the cursor to the beginning of the line, :kbd:`C-E`
+to the end, :kbd:`C-B` moves it one position to the left, :kbd:`C-F` to the
+right. Backspace erases the character to the left of the cursor, :kbd:`C-D` the
+character to its right. :kbd:`C-K` kills (erases) the rest of the line to the
+right of the cursor, :kbd:`C-Y` yanks back the last killed string.
+:kbd:`C-underscore` undoes the last change you made; it can be repeated for
+cumulative effect.
+
+
+.. _tut-history:
+
+History Substitution
+====================
+
+History substitution works as follows. All non-empty input lines issued are
+saved in a history buffer, and when a new prompt is given you are positioned on
+a new line at the bottom of this buffer. :kbd:`C-P` moves one line up (back) in
+the history buffer, :kbd:`C-N` moves one down. Any line in the history buffer
+can be edited; an asterisk appears in front of the prompt to mark a line as
+modified. Pressing the :kbd:`Return` key passes the current line to the
+interpreter. :kbd:`C-R` starts an incremental reverse search; :kbd:`C-S` starts
+a forward search.
+
+
+.. _tut-keybindings:
+
+Key Bindings
+============
+
+The key bindings and some other parameters of the Readline library can be
+customized by placing commands in an initialization file called
+:file:`~/.inputrc`. Key bindings have the form ::
+
+ key-name: function-name
+
+or ::
+
+ "string": function-name
+
+and options can be set with ::
+
+ set option-name value
+
+For example::
+
+ # I prefer vi-style editing:
+ set editing-mode vi
+
+ # Edit using a single line:
+ set horizontal-scroll-mode On
+
+ # Rebind some keys:
+ Meta-h: backward-kill-word
+ "\C-u": universal-argument
+ "\C-x\C-r": re-read-init-file
+
+Note that the default binding for :kbd:`Tab` in Python is to insert a :kbd:`Tab`
+character instead of Readline's default filename completion function. If you
+insist, you can override this by putting ::
+
+ Tab: complete
+
+in your :file:`~/.inputrc`. (Of course, this makes it harder to type indented
+continuation lines if you're accustomed to using :kbd:`Tab` for that purpose.)
+
+.. index::
+ module: rlcompleter
+ module: readline
+
+Automatic completion of variable and module names is optionally available. To
+enable it in the interpreter's interactive mode, add the following to your
+startup file: [#]_ ::
+
+ import rlcompleter, readline
+ readline.parse_and_bind('tab: complete')
+
+This binds the :kbd:`Tab` key to the completion function, so hitting the
+:kbd:`Tab` key twice suggests completions; it looks at Python statement names,
+the current local variables, and the available module names. For dotted
+expressions such as ``string.a``, it will evaluate the expression up to the
+final ``'.'`` and then suggest completions from the attributes of the resulting
+object. Note that this may execute application-defined code if an object with a
+:meth:`__getattr__` method is part of the expression.
+
+A more capable startup file might look like this example. Note that this
+deletes the names it creates once they are no longer needed; this is done since
+the startup file is executed in the same namespace as the interactive commands,
+and removing the names avoids creating side effects in the interactive
+environment. You may find it convenient to keep some of the imported modules,
+such as :mod:`os`, which turn out to be needed in most sessions with the
+interpreter. ::
+
+ # Add auto-completion and a stored history file of commands to your Python
+ # interactive interpreter. Requires Python 2.0+, readline. Autocomplete is
+ # bound to the Esc key by default (you can change it - see readline docs).
+ #
+ # Store the file in ~/.pystartup, and set an environment variable to point
+ # to it: "export PYTHONSTARTUP=/max/home/itamar/.pystartup" in bash.
+ #
+ # Note that PYTHONSTARTUP does *not* expand "~", so you have to put in the
+ # full path to your home directory.
+
+ import atexit
+ import os
+ import readline
+ import rlcompleter
+
+ historyPath = os.path.expanduser("~/.pyhistory")
+
+ def save_history(historyPath=historyPath):
+ import readline
+ readline.write_history_file(historyPath)
+
+ if os.path.exists(historyPath):
+ readline.read_history_file(historyPath)
+
+ atexit.register(save_history)
+ del os, atexit, readline, rlcompleter, save_history, historyPath
+
+
+.. _tut-commentary:
+
+Commentary
+==========
+
+This facility is an enormous step forward compared to earlier versions of the
+interpreter; however, some wishes are left: It would be nice if the proper
+indentation were suggested on continuation lines (the parser knows if an indent
+token is required next). The completion mechanism might use the interpreter's
+symbol table. A command to check (or even suggest) matching parentheses,
+quotes, etc., would also be useful.
+
+
+.. rubric:: Footnotes
+
+.. [#] Python will execute the contents of a file identified by the
+ :envvar:`PYTHONSTARTUP` environment variable when you start an interactive
+ interpreter.
+
diff --git a/Doc/tutorial/interpreter.rst b/Doc/tutorial/interpreter.rst
new file mode 100644
index 0000000000..8b42090a56
--- /dev/null
+++ b/Doc/tutorial/interpreter.rst
@@ -0,0 +1,248 @@
+.. _tut-using:
+
+****************************
+Using the Python Interpreter
+****************************
+
+
+.. _tut-invoking:
+
+Invoking the Interpreter
+========================
+
+The Python interpreter is usually installed as :file:`/usr/local/bin/python` on
+those machines where it is available; putting :file:`/usr/local/bin` in your
+Unix shell's search path makes it possible to start it by typing the command ::
+
+ python
+
+to the shell. Since the choice of the directory where the interpreter lives is
+an installation option, other places are possible; check with your local Python
+guru or system administrator. (E.g., :file:`/usr/local/python` is a popular
+alternative location.)
+
+On Windows machines, the Python installation is usually placed in
+:file:`C:\Python30`, though you can change this when you're running the
+installer. To add this directory to your path, you can type the following
+command into the command prompt in a DOS box::
+
+ set path=%path%;C:\python30
+
+Typing an end-of-file character (:kbd:`Control-D` on Unix, :kbd:`Control-Z` on
+Windows) at the primary prompt causes the interpreter to exit with a zero exit
+status. If that doesn't work, you can exit the interpreter by typing the
+following commands: ``import sys; sys.exit()``.
+
+The interpreter's line-editing features usually aren't very sophisticated. On
+Unix, whoever installed the interpreter may have enabled support for the GNU
+readline library, which adds more elaborate interactive editing and history
+features. Perhaps the quickest check to see whether command line editing is
+supported is typing Control-P to the first Python prompt you get. If it beeps,
+you have command line editing; see Appendix :ref:`tut-interacting` for an
+introduction to the keys. If nothing appears to happen, or if ``^P`` is echoed,
+command line editing isn't available; you'll only be able to use backspace to
+remove characters from the current line.
+
+The interpreter operates somewhat like the Unix shell: when called with standard
+input connected to a tty device, it reads and executes commands interactively;
+when called with a file name argument or with a file as standard input, it reads
+and executes a *script* from that file.
+
+A second way of starting the interpreter is ``python -c command [arg] ...``,
+which executes the statement(s) in *command*, analogous to the shell's
+:option:`-c` option. Since Python statements often contain spaces or other
+characters that are special to the shell, it is best to quote *command* in its
+entirety with double quotes.
+
+Some Python modules are also useful as scripts. These can be invoked using
+``python -m module [arg] ...``, which executes the source file for *module* as
+if you had spelled out its full name on the command line.
+
+Note that there is a difference between ``python file`` and ``python <file``.
+In the latter case, input requests from the program, such as calling
+``sys.stdin.read()``, are satisfied from *file*. Since this file has already
+been read until the end by the parser before the program starts executing, the
+program will encounter end-of-file immediately. In the former case (which is
+usually what you want) they are satisfied from whatever file or device is
+connected to standard input of the Python interpreter.
+
+When a script file is used, it is sometimes useful to be able to run the script
+and enter interactive mode afterwards. This can be done by passing :option:`-i`
+before the script. (This does not work if the script is read from standard
+input, for the same reason as explained in the previous paragraph.)
+
+
+.. _tut-argpassing:
+
+Argument Passing
+----------------
+
+When known to the interpreter, the script name and additional arguments
+thereafter are passed to the script in the variable ``sys.argv``, which is a
+list of strings. Its length is at least one; when no script and no arguments
+are given, ``sys.argv[0]`` is an empty string. When the script name is given as
+``'-'`` (meaning standard input), ``sys.argv[0]`` is set to ``'-'``. When
+:option:`-c` *command* is used, ``sys.argv[0]`` is set to ``'-c'``. When
+:option:`-m` *module* is used, ``sys.argv[0]`` is set to the full name of the
+located module. Options found after :option:`-c` *command* or :option:`-m`
+*module* are not consumed by the Python interpreter's option processing but
+left in ``sys.argv`` for the command or module to handle.
+
+
+.. _tut-interactive:
+
+Interactive Mode
+----------------
+
+When commands are read from a tty, the interpreter is said to be in *interactive
+mode*. In this mode it prompts for the next command with the *primary prompt*,
+usually three greater-than signs (``>>>``); for continuation lines it prompts
+with the *secondary prompt*, by default three dots (``...``). The interpreter
+prints a welcome message stating its version number and a copyright notice
+before printing the first prompt::
+
+ python
+ Python 1.5.2b2 (#1, Feb 28 1999, 00:02:06) [GCC 2.8.1] on sunos5
+ Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
+ >>>
+
+Continuation lines are needed when entering a multi-line construct. As an
+example, take a look at this :keyword:`if` statement::
+
+ >>> the_world_is_flat = 1
+ >>> if the_world_is_flat:
+ ... print "Be careful not to fall off!"
+ ...
+ Be careful not to fall off!
+
+
+.. _tut-interp:
+
+The Interpreter and Its Environment
+===================================
+
+
+.. _tut-error:
+
+Error Handling
+--------------
+
+When an error occurs, the interpreter prints an error message and a stack trace.
+In interactive mode, it then returns to the primary prompt; when input came from
+a file, it exits with a nonzero exit status after printing the stack trace.
+(Exceptions handled by an :keyword:`except` clause in a :keyword:`try` statement
+are not errors in this context.) Some errors are unconditionally fatal and
+cause an exit with a nonzero exit; this applies to internal inconsistencies and
+some cases of running out of memory. All error messages are written to the
+standard error stream; normal output from executed commands is written to
+standard output.
+
+Typing the interrupt character (usually Control-C or DEL) to the primary or
+secondary prompt cancels the input and returns to the primary prompt. [#]_
+Typing an interrupt while a command is executing raises the
+:exc:`KeyboardInterrupt` exception, which may be handled by a :keyword:`try`
+statement.
+
+
+.. _tut-scripts:
+
+Executable Python Scripts
+-------------------------
+
+On BSD'ish Unix systems, Python scripts can be made directly executable, like
+shell scripts, by putting the line ::
+
+ #! /usr/bin/env python
+
+(assuming that the interpreter is on the user's :envvar:`PATH`) at the beginning
+of the script and giving the file an executable mode. The ``#!`` must be the
+first two characters of the file. On some platforms, this first line must end
+with a Unix-style line ending (``'\n'``), not a Mac OS (``'\r'``) or Windows
+(``'\r\n'``) line ending. Note that the hash, or pound, character, ``'#'``, is
+used to start a comment in Python.
+
+The script can be given an executable mode, or permission, using the
+:program:`chmod` command::
+
+ $ chmod +x myscript.py
+
+
+Source Code Encoding
+--------------------
+
+It is possible to use encodings different than ASCII in Python source files. The
+best way to do it is to put one more special comment line right after the ``#!``
+line to define the source file encoding::
+
+ # -*- coding: encoding -*-
+
+
+With that declaration, all characters in the source file will be treated as
+having the encoding *encoding*, and it will be possible to directly write
+Unicode string literals in the selected encoding. The list of possible
+encodings can be found in the Python Library Reference, in the section on
+:mod:`codecs`.
+
+For example, to write Unicode literals including the Euro currency symbol, the
+ISO-8859-15 encoding can be used, with the Euro symbol having the ordinal value
+164. This script will print the value 8364 (the Unicode codepoint corresponding
+to the Euro symbol) and then exit::
+
+ # -*- coding: iso-8859-15 -*-
+
+ currency = u"€"
+ print ord(currency)
+
+If your editor supports saving files as ``UTF-8`` with a UTF-8 *byte order mark*
+(aka BOM), you can use that instead of an encoding declaration. IDLE supports
+this capability if ``Options/General/Default Source Encoding/UTF-8`` is set.
+Notice that this signature is not understood in older Python releases (2.2 and
+earlier), and also not understood by the operating system for script files with
+``#!`` lines (only used on Unix systems).
+
+By using UTF-8 (either through the signature or an encoding declaration),
+characters of most languages in the world can be used simultaneously in string
+literals and comments. Using non-ASCII characters in identifiers is not
+supported. To display all these characters properly, your editor must recognize
+that the file is UTF-8, and it must use a font that supports all the characters
+in the file.
+
+
+.. _tut-startup:
+
+The Interactive Startup File
+----------------------------
+
+When you use Python interactively, it is frequently handy to have some standard
+commands executed every time the interpreter is started. You can do this by
+setting an environment variable named :envvar:`PYTHONSTARTUP` to the name of a
+file containing your start-up commands. This is similar to the :file:`.profile`
+feature of the Unix shells.
+
+.. % XXX This should probably be dumped in an appendix, since most people
+.. % don't use Python interactively in non-trivial ways.
+
+This file is only read in interactive sessions, not when Python reads commands
+from a script, and not when :file:`/dev/tty` is given as the explicit source of
+commands (which otherwise behaves like an interactive session). It is executed
+in the same namespace where interactive commands are executed, so that objects
+that it defines or imports can be used without qualification in the interactive
+session. You can also change the prompts ``sys.ps1`` and ``sys.ps2`` in this
+file.
+
+If you want to read an additional start-up file from the current directory, you
+can program this in the global start-up file using code like ``if
+os.path.isfile('.pythonrc.py'): exec(open('.pythonrc.py').read())``.
+If you want to use the startup file in a script, you must do this explicitly
+in the script::
+
+ import os
+ filename = os.environ.get('PYTHONSTARTUP')
+ if filename and os.path.isfile(filename):
+ exec(open(filename).read())
+
+
+.. rubric:: Footnotes
+
+.. [#] A problem with the GNU Readline package may prevent this.
+
diff --git a/Doc/tutorial/introduction.rst b/Doc/tutorial/introduction.rst
new file mode 100644
index 0000000000..e209bfcc0e
--- /dev/null
+++ b/Doc/tutorial/introduction.rst
@@ -0,0 +1,645 @@
+.. _tut-informal:
+
+**********************************
+An Informal Introduction to Python
+**********************************
+
+In the following examples, input and output are distinguished by the presence or
+absence of prompts (``>>>`` and ``...``): to repeat the example, you must type
+everything after the prompt, when the prompt appears; lines that do not begin
+with a prompt are output from the interpreter. Note that a secondary prompt on a
+line by itself in an example means you must type a blank line; this is used to
+end a multi-line command.
+
+.. %
+.. % \footnote{
+.. % I'd prefer to use different fonts to distinguish input
+.. % from output, but the amount of LaTeX hacking that would require
+.. % is currently beyond my ability.
+.. % }
+
+Many of the examples in this manual, even those entered at the interactive
+prompt, include comments. Comments in Python start with the hash character,
+``'#'``, and extend to the end of the physical line. A comment may appear at
+the start of a line or following whitespace or code, but not within a string
+literal. A hash character within a string literal is just a hash character.
+
+Some examples::
+
+ # this is the first comment
+ SPAM = 1 # and this is the second comment
+ # ... and now a third!
+ STRING = "# This is not a comment."
+
+
+.. _tut-calculator:
+
+Using Python as a Calculator
+============================
+
+Let's try some simple Python commands. Start the interpreter and wait for the
+primary prompt, ``>>>``. (It shouldn't take long.)
+
+
+.. _tut-numbers:
+
+Numbers
+-------
+
+The interpreter acts as a simple calculator: you can type an expression at it
+and it will write the value. Expression syntax is straightforward: the
+operators ``+``, ``-``, ``*`` and ``/`` work just like in most other languages
+(for example, Pascal or C); parentheses can be used for grouping. For example::
+
+ >>> 2+2
+ 4
+ >>> # This is a comment
+ ... 2+2
+ 4
+ >>> 2+2 # and a comment on the same line as code
+ 4
+ >>> (50-5*6)/4
+ 5
+ >>> # Integer division returns the floor:
+ ... 7/3
+ 2
+ >>> 7/-3
+ -3
+
+The equal sign (``'='``) is used to assign a value to a variable. Afterwards, no
+result is displayed before the next interactive prompt::
+
+ >>> width = 20
+ >>> height = 5*9
+ >>> width * height
+ 900
+
+A value can be assigned to several variables simultaneously::
+
+ >>> x = y = z = 0 # Zero x, y and z
+ >>> x
+ 0
+ >>> y
+ 0
+ >>> z
+ 0
+
+There is full support for floating point; operators with mixed type operands
+convert the integer operand to floating point::
+
+ >>> 3 * 3.75 / 1.5
+ 7.5
+ >>> 7.0 / 2
+ 3.5
+
+Complex numbers are also supported; imaginary numbers are written with a suffix
+of ``j`` or ``J``. Complex numbers with a nonzero real component are written as
+``(real+imagj)``, or can be created with the ``complex(real, imag)`` function.
+::
+
+ >>> 1j * 1J
+ (-1+0j)
+ >>> 1j * complex(0,1)
+ (-1+0j)
+ >>> 3+1j*3
+ (3+3j)
+ >>> (3+1j)*3
+ (9+3j)
+ >>> (1+2j)/(1+1j)
+ (1.5+0.5j)
+
+Complex numbers are always represented as two floating point numbers, the real
+and imaginary part. To extract these parts from a complex number *z*, use
+``z.real`` and ``z.imag``. ::
+
+ >>> a=1.5+0.5j
+ >>> a.real
+ 1.5
+ >>> a.imag
+ 0.5
+
+The conversion functions to floating point and integer (:func:`float`,
+:func:`int` and :func:`long`) don't work for complex numbers --- there is no one
+correct way to convert a complex number to a real number. Use ``abs(z)`` to get
+its magnitude (as a float) or ``z.real`` to get its real part. ::
+
+ >>> a=3.0+4.0j
+ >>> float(a)
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: can't convert complex to float; use abs(z)
+ >>> a.real
+ 3.0
+ >>> a.imag
+ 4.0
+ >>> abs(a) # sqrt(a.real**2 + a.imag**2)
+ 5.0
+ >>>
+
+In interactive mode, the last printed expression is assigned to the variable
+``_``. This means that when you are using Python as a desk calculator, it is
+somewhat easier to continue calculations, for example::
+
+ >>> tax = 12.5 / 100
+ >>> price = 100.50
+ >>> price * tax
+ 12.5625
+ >>> price + _
+ 113.0625
+ >>> round(_, 2)
+ 113.06
+ >>>
+
+This variable should be treated as read-only by the user. Don't explicitly
+assign a value to it --- you would create an independent local variable with the
+same name masking the built-in variable with its magic behavior.
+
+
+.. _tut-strings:
+
+Strings
+-------
+
+Besides numbers, Python can also manipulate strings, which can be expressed in
+several ways. They can be enclosed in single quotes or double quotes::
+
+ >>> 'spam eggs'
+ 'spam eggs'
+ >>> 'doesn\'t'
+ "doesn't"
+ >>> "doesn't"
+ "doesn't"
+ >>> '"Yes," he said.'
+ '"Yes," he said.'
+ >>> "\"Yes,\" he said."
+ '"Yes," he said.'
+ >>> '"Isn\'t," she said.'
+ '"Isn\'t," she said.'
+
+String literals can span multiple lines in several ways. Continuation lines can
+be used, with a backslash as the last character on the line indicating that the
+next line is a logical continuation of the line::
+
+ hello = "This is a rather long string containing\n\
+ several lines of text just as you would do in C.\n\
+ Note that whitespace at the beginning of the line is\
+ significant."
+
+ print hello
+
+Note that newlines still need to be embedded in the string using ``\n``; the
+newline following the trailing backslash is discarded. This example would print
+the following::
+
+ This is a rather long string containing
+ several lines of text just as you would do in C.
+ Note that whitespace at the beginning of the line is significant.
+
+If we make the string literal a "raw" string, however, the ``\n`` sequences are
+not converted to newlines, but the backslash at the end of the line, and the
+newline character in the source, are both included in the string as data. Thus,
+the example::
+
+ hello = r"This is a rather long string containing\n\
+ several lines of text much as you would do in C."
+
+ print hello
+
+would print::
+
+ This is a rather long string containing\n\
+ several lines of text much as you would do in C.
+
+Or, strings can be surrounded in a pair of matching triple-quotes: ``"""`` or
+``'''``. End of lines do not need to be escaped when using triple-quotes, but
+they will be included in the string. ::
+
+ print """
+ Usage: thingy [OPTIONS]
+ -h Display this usage message
+ -H hostname Hostname to connect to
+ """
+
+produces the following output::
+
+ Usage: thingy [OPTIONS]
+ -h Display this usage message
+ -H hostname Hostname to connect to
+
+The interpreter prints the result of string operations in the same way as they
+are typed for input: inside quotes, and with quotes and other funny characters
+escaped by backslashes, to show the precise value. The string is enclosed in
+double quotes if the string contains a single quote and no double quotes, else
+it's enclosed in single quotes. (The :keyword:`print` statement, described
+later, can be used to write strings without quotes or escapes.)
+
+Strings can be concatenated (glued together) with the ``+`` operator, and
+repeated with ``*``::
+
+ >>> word = 'Help' + 'A'
+ >>> word
+ 'HelpA'
+ >>> '<' + word*5 + '>'
+ '<HelpAHelpAHelpAHelpAHelpA>'
+
+Two string literals next to each other are automatically concatenated; the first
+line above could also have been written ``word = 'Help' 'A'``; this only works
+with two literals, not with arbitrary string expressions::
+
+ >>> 'str' 'ing' # <- This is ok
+ 'string'
+ >>> 'str'.strip() + 'ing' # <- This is ok
+ 'string'
+ >>> 'str'.strip() 'ing' # <- This is invalid
+ File "<stdin>", line 1, in ?
+ 'str'.strip() 'ing'
+ ^
+ SyntaxError: invalid syntax
+
+Strings can be subscripted (indexed); like in C, the first character of a string
+has subscript (index) 0. There is no separate character type; a character is
+simply a string of size one. Like in Icon, substrings can be specified with the
+*slice notation*: two indices separated by a colon. ::
+
+ >>> word[4]
+ 'A'
+ >>> word[0:2]
+ 'He'
+ >>> word[2:4]
+ 'lp'
+
+Slice indices have useful defaults; an omitted first index defaults to zero, an
+omitted second index defaults to the size of the string being sliced. ::
+
+ >>> word[:2] # The first two characters
+ 'He'
+ >>> word[2:] # Everything except the first two characters
+ 'lpA'
+
+Unlike a C string, Python strings cannot be changed. Assigning to an indexed
+position in the string results in an error::
+
+ >>> word[0] = 'x'
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: object doesn't support item assignment
+ >>> word[:1] = 'Splat'
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ TypeError: object doesn't support slice assignment
+
+However, creating a new string with the combined content is easy and efficient::
+
+ >>> 'x' + word[1:]
+ 'xelpA'
+ >>> 'Splat' + word[4]
+ 'SplatA'
+
+Here's a useful invariant of slice operations: ``s[:i] + s[i:]`` equals ``s``.
+::
+
+ >>> word[:2] + word[2:]
+ 'HelpA'
+ >>> word[:3] + word[3:]
+ 'HelpA'
+
+Degenerate slice indices are handled gracefully: an index that is too large is
+replaced by the string size, an upper bound smaller than the lower bound returns
+an empty string. ::
+
+ >>> word[1:100]
+ 'elpA'
+ >>> word[10:]
+ ''
+ >>> word[2:1]
+ ''
+
+Indices may be negative numbers, to start counting from the right. For example::
+
+ >>> word[-1] # The last character
+ 'A'
+ >>> word[-2] # The last-but-one character
+ 'p'
+ >>> word[-2:] # The last two characters
+ 'pA'
+ >>> word[:-2] # Everything except the last two characters
+ 'Hel'
+
+But note that -0 is really the same as 0, so it does not count from the right!
+::
+
+ >>> word[-0] # (since -0 equals 0)
+ 'H'
+
+Out-of-range negative slice indices are truncated, but don't try this for
+single-element (non-slice) indices::
+
+ >>> word[-100:]
+ 'HelpA'
+ >>> word[-10] # error
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ IndexError: string index out of range
+
+One way to remember how slices work is to think of the indices as pointing
+*between* characters, with the left edge of the first character numbered 0.
+Then the right edge of the last character of a string of *n* characters has
+index *n*, for example::
+
+ +---+---+---+---+---+
+ | H | e | l | p | A |
+ +---+---+---+---+---+
+ 0 1 2 3 4 5
+ -5 -4 -3 -2 -1
+
+The first row of numbers gives the position of the indices 0...5 in the string;
+the second row gives the corresponding negative indices. The slice from *i* to
+*j* consists of all characters between the edges labeled *i* and *j*,
+respectively.
+
+For non-negative indices, the length of a slice is the difference of the
+indices, if both are within bounds. For example, the length of ``word[1:3]`` is
+2.
+
+The built-in function :func:`len` returns the length of a string::
+
+ >>> s = 'supercalifragilisticexpialidocious'
+ >>> len(s)
+ 34
+
+
+.. seealso::
+
+ :ref:`typesseq`
+ Strings, and the Unicode strings described in the next section, are
+ examples of *sequence types*, and support the common operations supported
+ by such types.
+
+ :ref:`string-methods`
+ Both strings and Unicode strings support a large number of methods for
+ basic transformations and searching.
+
+ :ref:`string-formatting`
+ The formatting operations invoked when strings and Unicode strings are the
+ left operand of the ``%`` operator are described in more detail here.
+
+
+.. _tut-unicodestrings:
+
+Unicode Strings
+---------------
+
+.. sectionauthor:: Marc-Andre Lemburg <mal@lemburg.com>
+
+
+Starting with Python 2.0 a new data type for storing text data is available to
+the programmer: the Unicode object. It can be used to store and manipulate
+Unicode data (see http://www.unicode.org/) and integrates well with the existing
+string objects, providing auto-conversions where necessary.
+
+Unicode has the advantage of providing one ordinal for every character in every
+script used in modern and ancient texts. Previously, there were only 256
+possible ordinals for script characters. Texts were typically bound to a code
+page which mapped the ordinals to script characters. This lead to very much
+confusion especially with respect to internationalization (usually written as
+``i18n`` --- ``'i'`` + 18 characters + ``'n'``) of software. Unicode solves
+these problems by defining one code page for all scripts.
+
+Creating Unicode strings in Python is just as simple as creating normal
+strings::
+
+ >>> u'Hello World !'
+ u'Hello World !'
+
+The small ``'u'`` in front of the quote indicates that a Unicode string is
+supposed to be created. If you want to include special characters in the string,
+you can do so by using the Python *Unicode-Escape* encoding. The following
+example shows how::
+
+ >>> u'Hello\u0020World !'
+ u'Hello World !'
+
+The escape sequence ``\u0020`` indicates to insert the Unicode character with
+the ordinal value 0x0020 (the space character) at the given position.
+
+Other characters are interpreted by using their respective ordinal values
+directly as Unicode ordinals. If you have literal strings in the standard
+Latin-1 encoding that is used in many Western countries, you will find it
+convenient that the lower 256 characters of Unicode are the same as the 256
+characters of Latin-1.
+
+For experts, there is also a raw mode just like the one for normal strings. You
+have to prefix the opening quote with 'ur' to have Python use the
+*Raw-Unicode-Escape* encoding. It will only apply the above ``\uXXXX``
+conversion if there is an uneven number of backslashes in front of the small
+'u'. ::
+
+ >>> ur'Hello\u0020World !'
+ u'Hello World !'
+ >>> ur'Hello\\u0020World !'
+ u'Hello\\\\u0020World !'
+
+The raw mode is most useful when you have to enter lots of backslashes, as can
+be necessary in regular expressions.
+
+Apart from these standard encodings, Python provides a whole set of other ways
+of creating Unicode strings on the basis of a known encoding.
+
+.. index:: builtin: unicode
+
+The built-in function :func:`unicode` provides access to all registered Unicode
+codecs (COders and DECoders). Some of the more well known encodings which these
+codecs can convert are *Latin-1*, *ASCII*, *UTF-8*, and *UTF-16*. The latter two
+are variable-length encodings that store each Unicode character in one or more
+bytes. The default encoding is normally set to ASCII, which passes through
+characters in the range 0 to 127 and rejects any other characters with an error.
+When a Unicode string is printed, written to a file, or converted with
+:func:`str`, conversion takes place using this default encoding. ::
+
+ >>> u"abc"
+ u'abc'
+ >>> str(u"abc")
+ 'abc'
+ >>> u"äöü"
+ u'\xe4\xf6\xfc'
+ >>> str(u"äöü")
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ UnicodeEncodeError: 'ascii' codec can't encode characters in position 0-2: ordinal not in range(128)
+
+To convert a Unicode string into an 8-bit string using a specific encoding,
+Unicode objects provide an :func:`encode` method that takes one argument, the
+name of the encoding. Lowercase names for encodings are preferred. ::
+
+ >>> u"äöü".encode('utf-8')
+ '\xc3\xa4\xc3\xb6\xc3\xbc'
+
+If you have data in a specific encoding and want to produce a corresponding
+Unicode string from it, you can use the :func:`unicode` function with the
+encoding name as the second argument. ::
+
+ >>> unicode('\xc3\xa4\xc3\xb6\xc3\xbc', 'utf-8')
+ u'\xe4\xf6\xfc'
+
+
+.. _tut-lists:
+
+Lists
+-----
+
+Python knows a number of *compound* data types, used to group together other
+values. The most versatile is the *list*, which can be written as a list of
+comma-separated values (items) between square brackets. List items need not all
+have the same type. ::
+
+ >>> a = ['spam', 'eggs', 100, 1234]
+ >>> a
+ ['spam', 'eggs', 100, 1234]
+
+Like string indices, list indices start at 0, and lists can be sliced,
+concatenated and so on::
+
+ >>> a[0]
+ 'spam'
+ >>> a[3]
+ 1234
+ >>> a[-2]
+ 100
+ >>> a[1:-1]
+ ['eggs', 100]
+ >>> a[:2] + ['bacon', 2*2]
+ ['spam', 'eggs', 'bacon', 4]
+ >>> 3*a[:3] + ['Boo!']
+ ['spam', 'eggs', 100, 'spam', 'eggs', 100, 'spam', 'eggs', 100, 'Boo!']
+
+Unlike strings, which are *immutable*, it is possible to change individual
+elements of a list::
+
+ >>> a
+ ['spam', 'eggs', 100, 1234]
+ >>> a[2] = a[2] + 23
+ >>> a
+ ['spam', 'eggs', 123, 1234]
+
+Assignment to slices is also possible, and this can even change the size of the
+list or clear it entirely::
+
+ >>> # Replace some items:
+ ... a[0:2] = [1, 12]
+ >>> a
+ [1, 12, 123, 1234]
+ >>> # Remove some:
+ ... a[0:2] = []
+ >>> a
+ [123, 1234]
+ >>> # Insert some:
+ ... a[1:1] = ['bletch', 'xyzzy']
+ >>> a
+ [123, 'bletch', 'xyzzy', 1234]
+ >>> # Insert (a copy of) itself at the beginning
+ >>> a[:0] = a
+ >>> a
+ [123, 'bletch', 'xyzzy', 1234, 123, 'bletch', 'xyzzy', 1234]
+ >>> # Clear the list: replace all items with an empty list
+ >>> a[:] = []
+ >>> a
+ []
+
+The built-in function :func:`len` also applies to lists::
+
+ >>> len(a)
+ 8
+
+It is possible to nest lists (create lists containing other lists), for
+example::
+
+ >>> q = [2, 3]
+ >>> p = [1, q, 4]
+ >>> len(p)
+ 3
+ >>> p[1]
+ [2, 3]
+ >>> p[1][0]
+ 2
+ >>> p[1].append('xtra') # See section 5.1
+ >>> p
+ [1, [2, 3, 'xtra'], 4]
+ >>> q
+ [2, 3, 'xtra']
+
+Note that in the last example, ``p[1]`` and ``q`` really refer to the same
+object! We'll come back to *object semantics* later.
+
+
+.. _tut-firststeps:
+
+First Steps Towards Programming
+===============================
+
+Of course, we can use Python for more complicated tasks than adding two and two
+together. For instance, we can write an initial sub-sequence of the *Fibonacci*
+series as follows::
+
+ >>> # Fibonacci series:
+ ... # the sum of two elements defines the next
+ ... a, b = 0, 1
+ >>> while b < 10:
+ ... print b
+ ... a, b = b, a+b
+ ...
+ 1
+ 1
+ 2
+ 3
+ 5
+ 8
+
+This example introduces several new features.
+
+* The first line contains a *multiple assignment*: the variables ``a`` and ``b``
+ simultaneously get the new values 0 and 1. On the last line this is used again,
+ demonstrating that the expressions on the right-hand side are all evaluated
+ first before any of the assignments take place. The right-hand side expressions
+ are evaluated from the left to the right.
+
+* The :keyword:`while` loop executes as long as the condition (here: ``b < 10``)
+ remains true. In Python, like in C, any non-zero integer value is true; zero is
+ false. The condition may also be a string or list value, in fact any sequence;
+ anything with a non-zero length is true, empty sequences are false. The test
+ used in the example is a simple comparison. The standard comparison operators
+ are written the same as in C: ``<`` (less than), ``>`` (greater than), ``==``
+ (equal to), ``<=`` (less than or equal to), ``>=`` (greater than or equal to)
+ and ``!=`` (not equal to).
+
+* The *body* of the loop is *indented*: indentation is Python's way of grouping
+ statements. Python does not (yet!) provide an intelligent input line editing
+ facility, so you have to type a tab or space(s) for each indented line. In
+ practice you will prepare more complicated input for Python with a text editor;
+ most text editors have an auto-indent facility. When a compound statement is
+ entered interactively, it must be followed by a blank line to indicate
+ completion (since the parser cannot guess when you have typed the last line).
+ Note that each line within a basic block must be indented by the same amount.
+
+* The :keyword:`print` statement writes the value of the expression(s) it is
+ given. It differs from just writing the expression you want to write (as we did
+ earlier in the calculator examples) in the way it handles multiple expressions
+ and strings. Strings are printed without quotes, and a space is inserted
+ between items, so you can format things nicely, like this::
+
+ >>> i = 256*256
+ >>> print 'The value of i is', i
+ The value of i is 65536
+
+ A trailing comma avoids the newline after the output::
+
+ >>> a, b = 0, 1
+ >>> while b < 1000:
+ ... print b,
+ ... a, b = b, a+b
+ ...
+ 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987
+
+ Note that the interpreter inserts a newline before it prints the next prompt if
+ the last line was not completed.
+
+
diff --git a/Doc/tutorial/modules.rst b/Doc/tutorial/modules.rst
new file mode 100644
index 0000000000..0b0dabdc13
--- /dev/null
+++ b/Doc/tutorial/modules.rst
@@ -0,0 +1,551 @@
+.. _tut-modules:
+
+*******
+Modules
+*******
+
+If you quit from the Python interpreter and enter it again, the definitions you
+have made (functions and variables) are lost. Therefore, if you want to write a
+somewhat longer program, you are better off using a text editor to prepare the
+input for the interpreter and running it with that file as input instead. This
+is known as creating a *script*. As your program gets longer, you may want to
+split it into several files for easier maintenance. You may also want to use a
+handy function that you've written in several programs without copying its
+definition into each program.
+
+To support this, Python has a way to put definitions in a file and use them in a
+script or in an interactive instance of the interpreter. Such a file is called a
+*module*; definitions from a module can be *imported* into other modules or into
+the *main* module (the collection of variables that you have access to in a
+script executed at the top level and in calculator mode).
+
+A module is a file containing Python definitions and statements. The file name
+is the module name with the suffix :file:`.py` appended. Within a module, the
+module's name (as a string) is available as the value of the global variable
+``__name__``. For instance, use your favorite text editor to create a file
+called :file:`fibo.py` in the current directory with the following contents::
+
+ # Fibonacci numbers module
+
+ def fib(n): # write Fibonacci series up to n
+ a, b = 0, 1
+ while b < n:
+ print b,
+ a, b = b, a+b
+
+ def fib2(n): # return Fibonacci series up to n
+ result = []
+ a, b = 0, 1
+ while b < n:
+ result.append(b)
+ a, b = b, a+b
+ return result
+
+Now enter the Python interpreter and import this module with the following
+command::
+
+ >>> import fibo
+
+This does not enter the names of the functions defined in ``fibo`` directly in
+the current symbol table; it only enters the module name ``fibo`` there. Using
+the module name you can access the functions::
+
+ >>> fibo.fib(1000)
+ 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987
+ >>> fibo.fib2(100)
+ [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
+ >>> fibo.__name__
+ 'fibo'
+
+If you intend to use a function often you can assign it to a local name::
+
+ >>> fib = fibo.fib
+ >>> fib(500)
+ 1 1 2 3 5 8 13 21 34 55 89 144 233 377
+
+
+.. _tut-moremodules:
+
+More on Modules
+===============
+
+A module can contain executable statements as well as function definitions.
+These statements are intended to initialize the module. They are executed only
+the *first* time the module is imported somewhere. [#]_
+
+Each module has its own private symbol table, which is used as the global symbol
+table by all functions defined in the module. Thus, the author of a module can
+use global variables in the module without worrying about accidental clashes
+with a user's global variables. On the other hand, if you know what you are
+doing you can touch a module's global variables with the same notation used to
+refer to its functions, ``modname.itemname``.
+
+Modules can import other modules. It is customary but not required to place all
+:keyword:`import` statements at the beginning of a module (or script, for that
+matter). The imported module names are placed in the importing module's global
+symbol table.
+
+There is a variant of the :keyword:`import` statement that imports names from a
+module directly into the importing module's symbol table. For example::
+
+ >>> from fibo import fib, fib2
+ >>> fib(500)
+ 1 1 2 3 5 8 13 21 34 55 89 144 233 377
+
+This does not introduce the module name from which the imports are taken in the
+local symbol table (so in the example, ``fibo`` is not defined).
+
+There is even a variant to import all names that a module defines::
+
+ >>> from fibo import *
+ >>> fib(500)
+ 1 1 2 3 5 8 13 21 34 55 89 144 233 377
+
+This imports all names except those beginning with an underscore (``_``).
+
+
+.. _tut-modulesasscripts:
+
+Executing modules as scripts
+----------------------------
+
+When you run a Python module with ::
+
+ python fibo.py <arguments>
+
+the code in the module will be executed, just as if you imported it, but with
+the ``__name__`` set to ``"__main__"``. That means that by adding this code at
+the end of your module::
+
+ if __name__ == "__main__":
+ import sys
+ fib(int(sys.argv[1]))
+
+you can make the file usable as a script as well as an importable module,
+because the code that parses the command line only runs if the module is
+executed as the "main" file::
+
+ $ python fibo.py 50
+ 1 1 2 3 5 8 13 21 34
+
+If the module is imported, the code is not run::
+
+ >>> import fibo
+ >>>
+
+This is often used either to provide a convenient user interface to a module, or
+for testing purposes (running the module as a script executes a test suite).
+
+
+.. _tut-searchpath:
+
+The Module Search Path
+----------------------
+
+.. index:: triple: module; search; path
+
+When a module named :mod:`spam` is imported, the interpreter searches for a file
+named :file:`spam.py` in the current directory, and then in the list of
+directories specified by the environment variable :envvar:`PYTHONPATH`. This
+has the same syntax as the shell variable :envvar:`PATH`, that is, a list of
+directory names. When :envvar:`PYTHONPATH` is not set, or when the file is not
+found there, the search continues in an installation-dependent default path; on
+Unix, this is usually :file:`.:/usr/local/lib/python`.
+
+Actually, modules are searched in the list of directories given by the variable
+``sys.path`` which is initialized from the directory containing the input script
+(or the current directory), :envvar:`PYTHONPATH` and the installation- dependent
+default. This allows Python programs that know what they're doing to modify or
+replace the module search path. Note that because the directory containing the
+script being run is on the search path, it is important that the script not have
+the same name as a standard module, or Python will attempt to load the script as
+a module when that module is imported. This will generally be an error. See
+section :ref:`tut-standardmodules` for more information.
+
+
+"Compiled" Python files
+-----------------------
+
+As an important speed-up of the start-up time for short programs that use a lot
+of standard modules, if a file called :file:`spam.pyc` exists in the directory
+where :file:`spam.py` is found, this is assumed to contain an
+already-"byte-compiled" version of the module :mod:`spam`. The modification time
+of the version of :file:`spam.py` used to create :file:`spam.pyc` is recorded in
+:file:`spam.pyc`, and the :file:`.pyc` file is ignored if these don't match.
+
+Normally, you don't need to do anything to create the :file:`spam.pyc` file.
+Whenever :file:`spam.py` is successfully compiled, an attempt is made to write
+the compiled version to :file:`spam.pyc`. It is not an error if this attempt
+fails; if for any reason the file is not written completely, the resulting
+:file:`spam.pyc` file will be recognized as invalid and thus ignored later. The
+contents of the :file:`spam.pyc` file are platform independent, so a Python
+module directory can be shared by machines of different architectures.
+
+Some tips for experts:
+
+* When the Python interpreter is invoked with the :option:`-O` flag, optimized
+ code is generated and stored in :file:`.pyo` files. The optimizer currently
+ doesn't help much; it only removes :keyword:`assert` statements. When
+ :option:`-O` is used, *all* bytecode is optimized; ``.pyc`` files are ignored
+ and ``.py`` files are compiled to optimized bytecode.
+
+* Passing two :option:`-O` flags to the Python interpreter (:option:`-OO`) will
+ cause the bytecode compiler to perform optimizations that could in some rare
+ cases result in malfunctioning programs. Currently only ``__doc__`` strings are
+ removed from the bytecode, resulting in more compact :file:`.pyo` files. Since
+ some programs may rely on having these available, you should only use this
+ option if you know what you're doing.
+
+* A program doesn't run any faster when it is read from a :file:`.pyc` or
+ :file:`.pyo` file than when it is read from a :file:`.py` file; the only thing
+ that's faster about :file:`.pyc` or :file:`.pyo` files is the speed with which
+ they are loaded.
+
+* When a script is run by giving its name on the command line, the bytecode for
+ the script is never written to a :file:`.pyc` or :file:`.pyo` file. Thus, the
+ startup time of a script may be reduced by moving most of its code to a module
+ and having a small bootstrap script that imports that module. It is also
+ possible to name a :file:`.pyc` or :file:`.pyo` file directly on the command
+ line.
+
+* It is possible to have a file called :file:`spam.pyc` (or :file:`spam.pyo`
+ when :option:`-O` is used) without a file :file:`spam.py` for the same module.
+ This can be used to distribute a library of Python code in a form that is
+ moderately hard to reverse engineer.
+
+ .. index:: module: compileall
+
+* The module :mod:`compileall` can create :file:`.pyc` files (or :file:`.pyo`
+ files when :option:`-O` is used) for all modules in a directory.
+
+ .. %
+
+
+.. _tut-standardmodules:
+
+Standard Modules
+================
+
+.. index:: module: sys
+
+Python comes with a library of standard modules, described in a separate
+document, the Python Library Reference ("Library Reference" hereafter). Some
+modules are built into the interpreter; these provide access to operations that
+are not part of the core of the language but are nevertheless built in, either
+for efficiency or to provide access to operating system primitives such as
+system calls. The set of such modules is a configuration option which also
+depends on the underlying platform For example, the :mod:`winreg` module is only
+provided on Windows systems. One particular module deserves some attention:
+:mod:`sys`, which is built into every Python interpreter. The variables
+``sys.ps1`` and ``sys.ps2`` define the strings used as primary and secondary
+prompts:
+
+.. %
+
+::
+
+ >>> import sys
+ >>> sys.ps1
+ '>>> '
+ >>> sys.ps2
+ '... '
+ >>> sys.ps1 = 'C> '
+ C> print 'Yuck!'
+ Yuck!
+ C>
+
+
+These two variables are only defined if the interpreter is in interactive mode.
+
+The variable ``sys.path`` is a list of strings that determines the interpreter's
+search path for modules. It is initialized to a default path taken from the
+environment variable :envvar:`PYTHONPATH`, or from a built-in default if
+:envvar:`PYTHONPATH` is not set. You can modify it using standard list
+operations::
+
+ >>> import sys
+ >>> sys.path.append('/ufs/guido/lib/python')
+
+
+.. _tut-dir:
+
+The :func:`dir` Function
+========================
+
+The built-in function :func:`dir` is used to find out which names a module
+defines. It returns a sorted list of strings::
+
+ >>> import fibo, sys
+ >>> dir(fibo)
+ ['__name__', 'fib', 'fib2']
+ >>> dir(sys)
+ ['__displayhook__', '__doc__', '__excepthook__', '__name__', '__stderr__',
+ '__stdin__', '__stdout__', '_getframe', 'api_version', 'argv',
+ 'builtin_module_names', 'byteorder', 'callstats', 'copyright',
+ 'displayhook', 'exc_info', 'excepthook',
+ 'exec_prefix', 'executable', 'exit', 'getdefaultencoding', 'getdlopenflags',
+ 'getrecursionlimit', 'getrefcount', 'hexversion', 'maxint', 'maxunicode',
+ 'meta_path', 'modules', 'path', 'path_hooks', 'path_importer_cache',
+ 'platform', 'prefix', 'ps1', 'ps2', 'setcheckinterval', 'setdlopenflags',
+ 'setprofile', 'setrecursionlimit', 'settrace', 'stderr', 'stdin', 'stdout',
+ 'version', 'version_info', 'warnoptions']
+
+Without arguments, :func:`dir` lists the names you have defined currently::
+
+ >>> a = [1, 2, 3, 4, 5]
+ >>> import fibo
+ >>> fib = fibo.fib
+ >>> dir()
+ ['__builtins__', '__doc__', '__file__', '__name__', 'a', 'fib', 'fibo', 'sys']
+
+Note that it lists all types of names: variables, modules, functions, etc.
+
+.. index:: module: __builtin__
+
+:func:`dir` does not list the names of built-in functions and variables. If you
+want a list of those, they are defined in the standard module
+:mod:`__builtin__`::
+
+ >>> import __builtin__
+ >>> dir(__builtin__)
+ ['ArithmeticError', 'AssertionError', 'AttributeError', 'DeprecationWarning',
+ 'EOFError', 'Ellipsis', 'EnvironmentError', 'Exception', 'False',
+ 'FloatingPointError', 'FutureWarning', 'IOError', 'ImportError',
+ 'IndentationError', 'IndexError', 'KeyError', 'KeyboardInterrupt',
+ 'LookupError', 'MemoryError', 'NameError', 'None', 'NotImplemented',
+ 'NotImplementedError', 'OSError', 'OverflowError',
+ 'PendingDeprecationWarning', 'ReferenceError', 'RuntimeError',
+ 'RuntimeWarning', 'StopIteration', 'SyntaxError',
+ 'SyntaxWarning', 'SystemError', 'SystemExit', 'TabError', 'True',
+ 'TypeError', 'UnboundLocalError', 'UnicodeDecodeError',
+ 'UnicodeEncodeError', 'UnicodeError', 'UnicodeTranslateError',
+ 'UserWarning', 'ValueError', 'Warning', 'WindowsError',
+ 'ZeroDivisionError', '_', '__debug__', '__doc__', '__import__',
+ '__name__', 'abs', 'basestring', 'bool', 'buffer',
+ 'chr', 'classmethod', 'cmp', 'compile',
+ 'complex', 'copyright', 'credits', 'delattr', 'dict', 'dir', 'divmod',
+ 'enumerate', 'eval', 'exec', 'exit', 'filter', 'float',
+ 'frozenset', 'getattr', 'globals', 'hasattr', 'hash', 'help', 'hex',
+ 'id', 'input', 'int', 'isinstance', 'issubclass', 'iter',
+ 'len', 'license', 'list', 'locals', 'map', 'max', 'min',
+ 'object', 'oct', 'open', 'ord', 'pow', 'property', 'quit', 'range',
+ 'repr', 'reversed', 'round', 'set',
+ 'setattr', 'slice', 'sorted', 'staticmethod', 'str', 'sum', 'super',
+ 'tuple', 'type', 'vars', 'zip']
+
+
+.. _tut-packages:
+
+Packages
+========
+
+Packages are a way of structuring Python's module namespace by using "dotted
+module names". For example, the module name :mod:`A.B` designates a submodule
+named ``B`` in a package named ``A``. Just like the use of modules saves the
+authors of different modules from having to worry about each other's global
+variable names, the use of dotted module names saves the authors of multi-module
+packages like NumPy or the Python Imaging Library from having to worry about
+each other's module names.
+
+Suppose you want to design a collection of modules (a "package") for the uniform
+handling of sound files and sound data. There are many different sound file
+formats (usually recognized by their extension, for example: :file:`.wav`,
+:file:`.aiff`, :file:`.au`), so you may need to create and maintain a growing
+collection of modules for the conversion between the various file formats.
+There are also many different operations you might want to perform on sound data
+(such as mixing, adding echo, applying an equalizer function, creating an
+artificial stereo effect), so in addition you will be writing a never-ending
+stream of modules to perform these operations. Here's a possible structure for
+your package (expressed in terms of a hierarchical filesystem)::
+
+ sound/ Top-level package
+ __init__.py Initialize the sound package
+ formats/ Subpackage for file format conversions
+ __init__.py
+ wavread.py
+ wavwrite.py
+ aiffread.py
+ aiffwrite.py
+ auread.py
+ auwrite.py
+ ...
+ effects/ Subpackage for sound effects
+ __init__.py
+ echo.py
+ surround.py
+ reverse.py
+ ...
+ filters/ Subpackage for filters
+ __init__.py
+ equalizer.py
+ vocoder.py
+ karaoke.py
+ ...
+
+When importing the package, Python searches through the directories on
+``sys.path`` looking for the package subdirectory.
+
+The :file:`__init__.py` files are required to make Python treat the directories
+as containing packages; this is done to prevent directories with a common name,
+such as ``string``, from unintentionally hiding valid modules that occur later
+on the module search path. In the simplest case, :file:`__init__.py` can just be
+an empty file, but it can also execute initialization code for the package or
+set the ``__all__`` variable, described later.
+
+Users of the package can import individual modules from the package, for
+example::
+
+ import sound.effects.echo
+
+This loads the submodule :mod:`sound.effects.echo`. It must be referenced with
+its full name. ::
+
+ sound.effects.echo.echofilter(input, output, delay=0.7, atten=4)
+
+An alternative way of importing the submodule is::
+
+ from sound.effects import echo
+
+This also loads the submodule :mod:`echo`, and makes it available without its
+package prefix, so it can be used as follows::
+
+ echo.echofilter(input, output, delay=0.7, atten=4)
+
+Yet another variation is to import the desired function or variable directly::
+
+ from sound.effects.echo import echofilter
+
+Again, this loads the submodule :mod:`echo`, but this makes its function
+:func:`echofilter` directly available::
+
+ echofilter(input, output, delay=0.7, atten=4)
+
+Note that when using ``from package import item``, the item can be either a
+submodule (or subpackage) of the package, or some other name defined in the
+package, like a function, class or variable. The ``import`` statement first
+tests whether the item is defined in the package; if not, it assumes it is a
+module and attempts to load it. If it fails to find it, an :exc:`ImportError`
+exception is raised.
+
+Contrarily, when using syntax like ``import item.subitem.subsubitem``, each item
+except for the last must be a package; the last item can be a module or a
+package but can't be a class or function or variable defined in the previous
+item.
+
+
+.. _tut-pkg-import-star:
+
+Importing \* From a Package
+---------------------------
+
+.. index:: single: __all__
+
+Now what happens when the user writes ``from sound.effects import *``? Ideally,
+one would hope that this somehow goes out to the filesystem, finds which
+submodules are present in the package, and imports them all. Unfortunately,
+this operation does not work very well on Windows platforms, where the
+filesystem does not always have accurate information about the case of a
+filename! On these platforms, there is no guaranteed way to know whether a file
+:file:`ECHO.PY` should be imported as a module :mod:`echo`, :mod:`Echo` or
+:mod:`ECHO`. (For example, Windows 95 has the annoying practice of showing all
+file names with a capitalized first letter.) The DOS 8+3 filename restriction
+adds another interesting problem for long module names.
+
+.. % The \code{__all__} Attribute
+
+The only solution is for the package author to provide an explicit index of the
+package. The import statement uses the following convention: if a package's
+:file:`__init__.py` code defines a list named ``__all__``, it is taken to be the
+list of module names that should be imported when ``from package import *`` is
+encountered. It is up to the package author to keep this list up-to-date when a
+new version of the package is released. Package authors may also decide not to
+support it, if they don't see a use for importing \* from their package. For
+example, the file :file:`sounds/effects/__init__.py` could contain the following
+code::
+
+ __all__ = ["echo", "surround", "reverse"]
+
+This would mean that ``from sound.effects import *`` would import the three
+named submodules of the :mod:`sound` package.
+
+If ``__all__`` is not defined, the statement ``from sound.effects import *``
+does *not* import all submodules from the package :mod:`sound.effects` into the
+current namespace; it only ensures that the package :mod:`sound.effects` has
+been imported (possibly running any initialization code in :file:`__init__.py`)
+and then imports whatever names are defined in the package. This includes any
+names defined (and submodules explicitly loaded) by :file:`__init__.py`. It
+also includes any submodules of the package that were explicitly loaded by
+previous import statements. Consider this code::
+
+ import sound.effects.echo
+ import sound.effects.surround
+ from sound.effects import *
+
+In this example, the echo and surround modules are imported in the current
+namespace because they are defined in the :mod:`sound.effects` package when the
+``from...import`` statement is executed. (This also works when ``__all__`` is
+defined.)
+
+Note that in general the practice of importing ``*`` from a module or package is
+frowned upon, since it often causes poorly readable code. However, it is okay to
+use it to save typing in interactive sessions, and certain modules are designed
+to export only names that follow certain patterns.
+
+Remember, there is nothing wrong with using ``from Package import
+specific_submodule``! In fact, this is the recommended notation unless the
+importing module needs to use submodules with the same name from different
+packages.
+
+
+Intra-package References
+------------------------
+
+The submodules often need to refer to each other. For example, the
+:mod:`surround` module might use the :mod:`echo` module. In fact, such
+references are so common that the :keyword:`import` statement first looks in the
+containing package before looking in the standard module search path. Thus, the
+:mod:`surround` module can simply use ``import echo`` or ``from echo import
+echofilter``. If the imported module is not found in the current package (the
+package of which the current module is a submodule), the :keyword:`import`
+statement looks for a top-level module with the given name.
+
+When packages are structured into subpackages (as with the :mod:`sound` package
+in the example), you can use absolute imports to refer to submodules of siblings
+packages. For example, if the module :mod:`sound.filters.vocoder` needs to use
+the :mod:`echo` module in the :mod:`sound.effects` package, it can use ``from
+sound.effects import echo``.
+
+Starting with Python 2.5, in addition to the implicit relative imports described
+above, you can write explicit relative imports with the ``from module import
+name`` form of import statement. These explicit relative imports use leading
+dots to indicate the current and parent packages involved in the relative
+import. From the :mod:`surround` module for example, you might use::
+
+ from . import echo
+ from .. import formats
+ from ..filters import equalizer
+
+Note that both explicit and implicit relative imports are based on the name of
+the current module. Since the name of the main module is always ``"__main__"``,
+modules intended for use as the main module of a Python application should
+always use absolute imports.
+
+
+Packages in Multiple Directories
+--------------------------------
+
+Packages support one more special attribute, :attr:`__path__`. This is
+initialized to be a list containing the name of the directory holding the
+package's :file:`__init__.py` before the code in that file is executed. This
+variable can be modified; doing so affects future searches for modules and
+subpackages contained in the package.
+
+While this feature is not often needed, it can be used to extend the set of
+modules found in a package.
+
+
+.. rubric:: Footnotes
+
+.. [#] In fact function definitions are also 'statements' that are 'executed'; the
+ execution enters the function name in the module's global symbol table.
+
diff --git a/Doc/tutorial/stdlib.rst b/Doc/tutorial/stdlib.rst
new file mode 100644
index 0000000000..7bbc5efa44
--- /dev/null
+++ b/Doc/tutorial/stdlib.rst
@@ -0,0 +1,313 @@
+.. _tut-brieftour:
+
+**********************************
+Brief Tour of the Standard Library
+**********************************
+
+
+.. _tut-os-interface:
+
+Operating System Interface
+==========================
+
+The :mod:`os` module provides dozens of functions for interacting with the
+operating system::
+
+ >>> import os
+ >>> os.system('time 0:02')
+ 0
+ >>> os.getcwd() # Return the current working directory
+ 'C:\\Python30'
+ >>> os.chdir('/server/accesslogs')
+
+Be sure to use the ``import os`` style instead of ``from os import *``. This
+will keep :func:`os.open` from shadowing the builtin :func:`open` function which
+operates much differently.
+
+.. index:: builtin: help
+
+The builtin :func:`dir` and :func:`help` functions are useful as interactive
+aids for working with large modules like :mod:`os`::
+
+ >>> import os
+ >>> dir(os)
+ <returns a list of all module functions>
+ >>> help(os)
+ <returns an extensive manual page created from the module's docstrings>
+
+For daily file and directory management tasks, the :mod:`shutil` module provides
+a higher level interface that is easier to use::
+
+ >>> import shutil
+ >>> shutil.copyfile('data.db', 'archive.db')
+ >>> shutil.move('/build/executables', 'installdir')
+
+
+.. _tut-file-wildcards:
+
+File Wildcards
+==============
+
+The :mod:`glob` module provides a function for making file lists from directory
+wildcard searches::
+
+ >>> import glob
+ >>> glob.glob('*.py')
+ ['primes.py', 'random.py', 'quote.py']
+
+
+.. _tut-command-line-arguments:
+
+Command Line Arguments
+======================
+
+Common utility scripts often need to process command line arguments. These
+arguments are stored in the :mod:`sys` module's *argv* attribute as a list. For
+instance the following output results from running ``python demo.py one two
+three`` at the command line::
+
+ >>> import sys
+ >>> print sys.argv
+ ['demo.py', 'one', 'two', 'three']
+
+The :mod:`getopt` module processes *sys.argv* using the conventions of the Unix
+:func:`getopt` function. More powerful and flexible command line processing is
+provided by the :mod:`optparse` module.
+
+
+.. _tut-stderr:
+
+Error Output Redirection and Program Termination
+================================================
+
+The :mod:`sys` module also has attributes for *stdin*, *stdout*, and *stderr*.
+The latter is useful for emitting warnings and error messages to make them
+visible even when *stdout* has been redirected::
+
+ >>> sys.stderr.write('Warning, log file not found starting a new one\n')
+ Warning, log file not found starting a new one
+
+The most direct way to terminate a script is to use ``sys.exit()``.
+
+
+.. _tut-string-pattern-matching:
+
+String Pattern Matching
+=======================
+
+The :mod:`re` module provides regular expression tools for advanced string
+processing. For complex matching and manipulation, regular expressions offer
+succinct, optimized solutions::
+
+ >>> import re
+ >>> re.findall(r'\bf[a-z]*', 'which foot or hand fell fastest')
+ ['foot', 'fell', 'fastest']
+ >>> re.sub(r'(\b[a-z]+) \1', r'\1', 'cat in the the hat')
+ 'cat in the hat'
+
+When only simple capabilities are needed, string methods are preferred because
+they are easier to read and debug::
+
+ >>> 'tea for too'.replace('too', 'two')
+ 'tea for two'
+
+
+.. _tut-mathematics:
+
+Mathematics
+===========
+
+The :mod:`math` module gives access to the underlying C library functions for
+floating point math::
+
+ >>> import math
+ >>> math.cos(math.pi / 4.0)
+ 0.70710678118654757
+ >>> math.log(1024, 2)
+ 10.0
+
+The :mod:`random` module provides tools for making random selections::
+
+ >>> import random
+ >>> random.choice(['apple', 'pear', 'banana'])
+ 'apple'
+ >>> random.sample(range(100), 10) # sampling without replacement
+ [30, 83, 16, 4, 8, 81, 41, 50, 18, 33]
+ >>> random.random() # random float
+ 0.17970987693706186
+ >>> random.randrange(6) # random integer chosen from range(6)
+ 4
+
+
+.. _tut-internet-access:
+
+Internet Access
+===============
+
+There are a number of modules for accessing the internet and processing internet
+protocols. Two of the simplest are :mod:`urllib2` for retrieving data from urls
+and :mod:`smtplib` for sending mail::
+
+ >>> import urllib2
+ >>> for line in urllib2.urlopen('http://tycho.usno.navy.mil/cgi-bin/timer.pl'):
+ ... if 'EST' in line or 'EDT' in line: # look for Eastern Time
+ ... print line
+
+ <BR>Nov. 25, 09:43:32 PM EST
+
+ >>> import smtplib
+ >>> server = smtplib.SMTP('localhost')
+ >>> server.sendmail('soothsayer@example.org', 'jcaesar@example.org',
+ """To: jcaesar@example.org
+ From: soothsayer@example.org
+
+ Beware the Ides of March.
+ """)
+ >>> server.quit()
+
+
+.. _tut-dates-and-times:
+
+Dates and Times
+===============
+
+The :mod:`datetime` module supplies classes for manipulating dates and times in
+both simple and complex ways. While date and time arithmetic is supported, the
+focus of the implementation is on efficient member extraction for output
+formatting and manipulation. The module also supports objects that are timezone
+aware. ::
+
+ # dates are easily constructed and formatted
+ >>> from datetime import date
+ >>> now = date.today()
+ >>> now
+ datetime.date(2003, 12, 2)
+ >>> now.strftime("%m-%d-%y. %d %b %Y is a %A on the %d day of %B.")
+ '12-02-03. 02 Dec 2003 is a Tuesday on the 02 day of December.'
+
+ # dates support calendar arithmetic
+ >>> birthday = date(1964, 7, 31)
+ >>> age = now - birthday
+ >>> age.days
+ 14368
+
+
+.. _tut-data-compression:
+
+Data Compression
+================
+
+Common data archiving and compression formats are directly supported by modules
+including: :mod:`zlib`, :mod:`gzip`, :mod:`bz2`, :mod:`zipfile` and
+:mod:`tarfile`. ::
+
+ >>> import zlib
+ >>> s = 'witch which has which witches wrist watch'
+ >>> len(s)
+ 41
+ >>> t = zlib.compress(s)
+ >>> len(t)
+ 37
+ >>> zlib.decompress(t)
+ 'witch which has which witches wrist watch'
+ >>> zlib.crc32(s)
+ 226805979
+
+
+.. _tut-performance-measurement:
+
+Performance Measurement
+=======================
+
+Some Python users develop a deep interest in knowing the relative performance of
+different approaches to the same problem. Python provides a measurement tool
+that answers those questions immediately.
+
+For example, it may be tempting to use the tuple packing and unpacking feature
+instead of the traditional approach to swapping arguments. The :mod:`timeit`
+module quickly demonstrates a modest performance advantage::
+
+ >>> from timeit import Timer
+ >>> Timer('t=a; a=b; b=t', 'a=1; b=2').timeit()
+ 0.57535828626024577
+ >>> Timer('a,b = b,a', 'a=1; b=2').timeit()
+ 0.54962537085770791
+
+In contrast to :mod:`timeit`'s fine level of granularity, the :mod:`profile` and
+:mod:`pstats` modules provide tools for identifying time critical sections in
+larger blocks of code.
+
+
+.. _tut-quality-control:
+
+Quality Control
+===============
+
+One approach for developing high quality software is to write tests for each
+function as it is developed and to run those tests frequently during the
+development process.
+
+The :mod:`doctest` module provides a tool for scanning a module and validating
+tests embedded in a program's docstrings. Test construction is as simple as
+cutting-and-pasting a typical call along with its results into the docstring.
+This improves the documentation by providing the user with an example and it
+allows the doctest module to make sure the code remains true to the
+documentation::
+
+ def average(values):
+ """Computes the arithmetic mean of a list of numbers.
+
+ >>> print average([20, 30, 70])
+ 40.0
+ """
+ return sum(values, 0.0) / len(values)
+
+ import doctest
+ doctest.testmod() # automatically validate the embedded tests
+
+The :mod:`unittest` module is not as effortless as the :mod:`doctest` module,
+but it allows a more comprehensive set of tests to be maintained in a separate
+file::
+
+ import unittest
+
+ class TestStatisticalFunctions(unittest.TestCase):
+
+ def test_average(self):
+ self.assertEqual(average([20, 30, 70]), 40.0)
+ self.assertEqual(round(average([1, 5, 7]), 1), 4.3)
+ self.assertRaises(ZeroDivisionError, average, [])
+ self.assertRaises(TypeError, average, 20, 30, 70)
+
+ unittest.main() # Calling from the command line invokes all tests
+
+
+.. _tut-batteries-included:
+
+Batteries Included
+==================
+
+Python has a "batteries included" philosophy. This is best seen through the
+sophisticated and robust capabilities of its larger packages. For example:
+
+* The :mod:`xmlrpclib` and :mod:`SimpleXMLRPCServer` modules make implementing
+ remote procedure calls into an almost trivial task. Despite the modules
+ names, no direct knowledge or handling of XML is needed.
+
+* The :mod:`email` package is a library for managing email messages, including
+ MIME and other RFC 2822-based message documents. Unlike :mod:`smtplib` and
+ :mod:`poplib` which actually send and receive messages, the email package has
+ a complete toolset for building or decoding complex message structures
+ (including attachments) and for implementing internet encoding and header
+ protocols.
+
+* The :mod:`xml.dom` and :mod:`xml.sax` packages provide robust support for
+ parsing this popular data interchange format. Likewise, the :mod:`csv` module
+ supports direct reads and writes in a common database format. Together, these
+ modules and packages greatly simplify data interchange between python
+ applications and other tools.
+
+* Internationalization is supported by a number of modules including
+ :mod:`gettext`, :mod:`locale`, and the :mod:`codecs` package.
+
+
diff --git a/Doc/tutorial/stdlib2.rst b/Doc/tutorial/stdlib2.rst
new file mode 100644
index 0000000000..0ce2757647
--- /dev/null
+++ b/Doc/tutorial/stdlib2.rst
@@ -0,0 +1,394 @@
+.. _tut-brieftourtwo:
+
+*********************************************
+Brief Tour of the Standard Library -- Part II
+*********************************************
+
+This second tour covers more advanced modules that support professional
+programming needs. These modules rarely occur in small scripts.
+
+
+.. _tut-output-formatting:
+
+Output Formatting
+=================
+
+The :mod:`repr` module provides a version of :func:`repr` customized for
+abbreviated displays of large or deeply nested containers::
+
+ >>> import repr
+ >>> repr.repr(set('supercalifragilisticexpialidocious'))
+ "set(['a', 'c', 'd', 'e', 'f', 'g', ...])"
+
+The :mod:`pprint` module offers more sophisticated control over printing both
+built-in and user defined objects in a way that is readable by the interpreter.
+When the result is longer than one line, the "pretty printer" adds line breaks
+and indentation to more clearly reveal data structure::
+
+ >>> import pprint
+ >>> t = [[[['black', 'cyan'], 'white', ['green', 'red']], [['magenta',
+ ... 'yellow'], 'blue']]]
+ ...
+ >>> pprint.pprint(t, width=30)
+ [[[['black', 'cyan'],
+ 'white',
+ ['green', 'red']],
+ [['magenta', 'yellow'],
+ 'blue']]]
+
+The :mod:`textwrap` module formats paragraphs of text to fit a given screen
+width::
+
+ >>> import textwrap
+ >>> doc = """The wrap() method is just like fill() except that it returns
+ ... a list of strings instead of one big string with newlines to separate
+ ... the wrapped lines."""
+ ...
+ >>> print textwrap.fill(doc, width=40)
+ The wrap() method is just like fill()
+ except that it returns a list of strings
+ instead of one big string with newlines
+ to separate the wrapped lines.
+
+The :mod:`locale` module accesses a database of culture specific data formats.
+The grouping attribute of locale's format function provides a direct way of
+formatting numbers with group separators::
+
+ >>> import locale
+ >>> locale.setlocale(locale.LC_ALL, 'English_United States.1252')
+ 'English_United States.1252'
+ >>> conv = locale.localeconv() # get a mapping of conventions
+ >>> x = 1234567.8
+ >>> locale.format("%d", x, grouping=True)
+ '1,234,567'
+ >>> locale.format("%s%.*f", (conv['currency_symbol'],
+ ... conv['frac_digits'], x), grouping=True)
+ '$1,234,567.80'
+
+
+.. _tut-templating:
+
+Templating
+==========
+
+The :mod:`string` module includes a versatile :class:`Template` class with a
+simplified syntax suitable for editing by end-users. This allows users to
+customize their applications without having to alter the application.
+
+The format uses placeholder names formed by ``$`` with valid Python identifiers
+(alphanumeric characters and underscores). Surrounding the placeholder with
+braces allows it to be followed by more alphanumeric letters with no intervening
+spaces. Writing ``$$`` creates a single escaped ``$``::
+
+ >>> from string import Template
+ >>> t = Template('${village}folk send $$10 to $cause.')
+ >>> t.substitute(village='Nottingham', cause='the ditch fund')
+ 'Nottinghamfolk send $10 to the ditch fund.'
+
+The :meth:`substitute` method raises a :exc:`KeyError` when a placeholder is not
+supplied in a dictionary or a keyword argument. For mail-merge style
+applications, user supplied data may be incomplete and the
+:meth:`safe_substitute` method may be more appropriate --- it will leave
+placeholders unchanged if data is missing::
+
+ >>> t = Template('Return the $item to $owner.')
+ >>> d = dict(item='unladen swallow')
+ >>> t.substitute(d)
+ Traceback (most recent call last):
+ . . .
+ KeyError: 'owner'
+ >>> t.safe_substitute(d)
+ 'Return the unladen swallow to $owner.'
+
+Template subclasses can specify a custom delimiter. For example, a batch
+renaming utility for a photo browser may elect to use percent signs for
+placeholders such as the current date, image sequence number, or file format::
+
+ >>> import time, os.path, sys
+ >>> def raw_input(prompt):
+ ... sys.stdout.write(prompt)
+ ... sys.stdout.flush()
+ ... return sys.stdin.readline()
+ ...
+ >>> photofiles = ['img_1074.jpg', 'img_1076.jpg', 'img_1077.jpg']
+ >>> class BatchRename(Template):
+ ... delimiter = '%'
+ >>> fmt = raw_input('Enter rename style (%d-date %n-seqnum %f-format): ')
+ Enter rename style (%d-date %n-seqnum %f-format): Ashley_%n%f
+
+ >>> t = BatchRename(fmt)
+ >>> date = time.strftime('%d%b%y')
+ >>> for i, filename in enumerate(photofiles):
+ ... base, ext = os.path.splitext(filename)
+ ... newname = t.substitute(d=date, n=i, f=ext)
+ ... print '%s --> %s' % (filename, newname)
+
+ img_1074.jpg --> Ashley_0.jpg
+ img_1076.jpg --> Ashley_1.jpg
+ img_1077.jpg --> Ashley_2.jpg
+
+Another application for templating is separating program logic from the details
+of multiple output formats. This makes it possible to substitute custom
+templates for XML files, plain text reports, and HTML web reports.
+
+
+.. _tut-binary-formats:
+
+Working with Binary Data Record Layouts
+=======================================
+
+The :mod:`struct` module provides :func:`pack` and :func:`unpack` functions for
+working with variable length binary record formats. The following example shows
+how to loop through header information in a ZIP file (with pack codes ``"H"``
+and ``"L"`` representing two and four byte unsigned numbers respectively)::
+
+ import struct
+
+ data = open('myfile.zip', 'rb').read()
+ start = 0
+ for i in range(3): # show the first 3 file headers
+ start += 14
+ fields = struct.unpack('LLLHH', data[start:start+16])
+ crc32, comp_size, uncomp_size, filenamesize, extra_size = fields
+
+ start += 16
+ filename = data[start:start+filenamesize]
+ start += filenamesize
+ extra = data[start:start+extra_size]
+ print filename, hex(crc32), comp_size, uncomp_size
+
+ start += extra_size + comp_size # skip to the next header
+
+
+.. _tut-multi-threading:
+
+Multi-threading
+===============
+
+Threading is a technique for decoupling tasks which are not sequentially
+dependent. Threads can be used to improve the responsiveness of applications
+that accept user input while other tasks run in the background. A related use
+case is running I/O in parallel with computations in another thread.
+
+The following code shows how the high level :mod:`threading` module can run
+tasks in background while the main program continues to run::
+
+ import threading, zipfile
+
+ class AsyncZip(threading.Thread):
+ def __init__(self, infile, outfile):
+ threading.Thread.__init__(self)
+ self.infile = infile
+ self.outfile = outfile
+ def run(self):
+ f = zipfile.ZipFile(self.outfile, 'w', zipfile.ZIP_DEFLATED)
+ f.write(self.infile)
+ f.close()
+ print 'Finished background zip of: ', self.infile
+
+ background = AsyncZip('mydata.txt', 'myarchive.zip')
+ background.start()
+ print 'The main program continues to run in foreground.'
+
+ background.join() # Wait for the background task to finish
+ print 'Main program waited until background was done.'
+
+The principal challenge of multi-threaded applications is coordinating threads
+that share data or other resources. To that end, the threading module provides
+a number of synchronization primitives including locks, events, condition
+variables, and semaphores.
+
+While those tools are powerful, minor design errors can result in problems that
+are difficult to reproduce. So, the preferred approach to task coordination is
+to concentrate all access to a resource in a single thread and then use the
+:mod:`Queue` module to feed that thread with requests from other threads.
+Applications using :class:`Queue` objects for inter-thread communication and
+coordination are easier to design, more readable, and more reliable.
+
+
+.. _tut-logging:
+
+Logging
+=======
+
+The :mod:`logging` module offers a full featured and flexible logging system.
+At its simplest, log messages are sent to a file or to ``sys.stderr``::
+
+ import logging
+ logging.debug('Debugging information')
+ logging.info('Informational message')
+ logging.warning('Warning:config file %s not found', 'server.conf')
+ logging.error('Error occurred')
+ logging.critical('Critical error -- shutting down')
+
+This produces the following output::
+
+ WARNING:root:Warning:config file server.conf not found
+ ERROR:root:Error occurred
+ CRITICAL:root:Critical error -- shutting down
+
+By default, informational and debugging messages are suppressed and the output
+is sent to standard error. Other output options include routing messages
+through email, datagrams, sockets, or to an HTTP Server. New filters can select
+different routing based on message priority: :const:`DEBUG`, :const:`INFO`,
+:const:`WARNING`, :const:`ERROR`, and :const:`CRITICAL`.
+
+The logging system can be configured directly from Python or can be loaded from
+a user editable configuration file for customized logging without altering the
+application.
+
+
+.. _tut-weak-references:
+
+Weak References
+===============
+
+Python does automatic memory management (reference counting for most objects and
+garbage collection to eliminate cycles). The memory is freed shortly after the
+last reference to it has been eliminated.
+
+This approach works fine for most applications but occasionally there is a need
+to track objects only as long as they are being used by something else.
+Unfortunately, just tracking them creates a reference that makes them permanent.
+The :mod:`weakref` module provides tools for tracking objects without creating a
+reference. When the object is no longer needed, it is automatically removed
+from a weakref table and a callback is triggered for weakref objects. Typical
+applications include caching objects that are expensive to create::
+
+ >>> import weakref, gc
+ >>> class A:
+ ... def __init__(self, value):
+ ... self.value = value
+ ... def __repr__(self):
+ ... return str(self.value)
+ ...
+ >>> a = A(10) # create a reference
+ >>> d = weakref.WeakValueDictionary()
+ >>> d['primary'] = a # does not create a reference
+ >>> d['primary'] # fetch the object if it is still alive
+ 10
+ >>> del a # remove the one reference
+ >>> gc.collect() # run garbage collection right away
+ 0
+ >>> d['primary'] # entry was automatically removed
+ Traceback (most recent call last):
+ File "<pyshell#108>", line 1, in -toplevel-
+ d['primary'] # entry was automatically removed
+ File "C:/python30/lib/weakref.py", line 46, in __getitem__
+ o = self.data[key]()
+ KeyError: 'primary'
+
+
+.. _tut-list-tools:
+
+Tools for Working with Lists
+============================
+
+Many data structure needs can be met with the built-in list type. However,
+sometimes there is a need for alternative implementations with different
+performance trade-offs.
+
+The :mod:`array` module provides an :class:`array()` object that is like a list
+that stores only homogenous data and stores it more compactly. The following
+example shows an array of numbers stored as two byte unsigned binary numbers
+(typecode ``"H"``) rather than the usual 16 bytes per entry for regular lists of
+python int objects::
+
+ >>> from array import array
+ >>> a = array('H', [4000, 10, 700, 22222])
+ >>> sum(a)
+ 26932
+ >>> a[1:3]
+ array('H', [10, 700])
+
+The :mod:`collections` module provides a :class:`deque()` object that is like a
+list with faster appends and pops from the left side but slower lookups in the
+middle. These objects are well suited for implementing queues and breadth first
+tree searches::
+
+ >>> from collections import deque
+ >>> d = deque(["task1", "task2", "task3"])
+ >>> d.append("task4")
+ >>> print "Handling", d.popleft()
+ Handling task1
+
+ unsearched = deque([starting_node])
+ def breadth_first_search(unsearched):
+ node = unsearched.popleft()
+ for m in gen_moves(node):
+ if is_goal(m):
+ return m
+ unsearched.append(m)
+
+In addition to alternative list implementations, the library also offers other
+tools such as the :mod:`bisect` module with functions for manipulating sorted
+lists::
+
+ >>> import bisect
+ >>> scores = [(100, 'perl'), (200, 'tcl'), (400, 'lua'), (500, 'python')]
+ >>> bisect.insort(scores, (300, 'ruby'))
+ >>> scores
+ [(100, 'perl'), (200, 'tcl'), (300, 'ruby'), (400, 'lua'), (500, 'python')]
+
+The :mod:`heapq` module provides functions for implementing heaps based on
+regular lists. The lowest valued entry is always kept at position zero. This
+is useful for applications which repeatedly access the smallest element but do
+not want to run a full list sort::
+
+ >>> from heapq import heapify, heappop, heappush
+ >>> data = [1, 3, 5, 7, 9, 2, 4, 6, 8, 0]
+ >>> heapify(data) # rearrange the list into heap order
+ >>> heappush(data, -5) # add a new entry
+ >>> [heappop(data) for i in range(3)] # fetch the three smallest entries
+ [-5, 0, 1]
+
+
+.. _tut-decimal-fp:
+
+Decimal Floating Point Arithmetic
+=================================
+
+The :mod:`decimal` module offers a :class:`Decimal` datatype for decimal
+floating point arithmetic. Compared to the built-in :class:`float`
+implementation of binary floating point, the new class is especially helpful for
+financial applications and other uses which require exact decimal
+representation, control over precision, control over rounding to meet legal or
+regulatory requirements, tracking of significant decimal places, or for
+applications where the user expects the results to match calculations done by
+hand.
+
+For example, calculating a 5% tax on a 70 cent phone charge gives different
+results in decimal floating point and binary floating point. The difference
+becomes significant if the results are rounded to the nearest cent::
+
+ >>> from decimal import *
+ >>> Decimal('0.70') * Decimal('1.05')
+ Decimal("0.7350")
+ >>> .70 * 1.05
+ 0.73499999999999999
+
+The :class:`Decimal` result keeps a trailing zero, automatically inferring four
+place significance from multiplicands with two place significance. Decimal
+reproduces mathematics as done by hand and avoids issues that can arise when
+binary floating point cannot exactly represent decimal quantities.
+
+Exact representation enables the :class:`Decimal` class to perform modulo
+calculations and equality tests that are unsuitable for binary floating point::
+
+ >>> Decimal('1.00') % Decimal('.10')
+ Decimal("0.00")
+ >>> 1.00 % 0.10
+ 0.09999999999999995
+
+ >>> sum([Decimal('0.1')]*10) == Decimal('1.0')
+ True
+ >>> sum([0.1]*10) == 1.0
+ False
+
+The :mod:`decimal` module provides arithmetic with as much precision as needed::
+
+ >>> getcontext().prec = 36
+ >>> Decimal(1) / Decimal(7)
+ Decimal("0.142857142857142857142857142857142857")
+
+
diff --git a/Doc/tutorial/whatnow.rst b/Doc/tutorial/whatnow.rst
new file mode 100644
index 0000000000..599fcbd026
--- /dev/null
+++ b/Doc/tutorial/whatnow.rst
@@ -0,0 +1,68 @@
+.. _tut-whatnow:
+
+*********
+What Now?
+*********
+
+Reading this tutorial has probably reinforced your interest in using Python ---
+you should be eager to apply Python to solving your real-world problems. Where
+should you go to learn more?
+
+This tutorial is part of Python's documentation set. Some other documents in
+the set are:
+
+* :ref:`library-index`:
+
+ You should browse through this manual, which gives complete (though terse)
+ reference material about types, functions, and the modules in the standard
+ library. The standard Python distribution includes a *lot* of additional code.
+ There are modules to read Unix mailboxes, retrieve documents via HTTP, generate
+ random numbers, parse command-line options, write CGI programs, compress data,
+ and many other tasks. Skimming through the Library Reference will give you an
+ idea of what's available.
+
+* :ref:`install-index` explains how to install external modules written by other
+ Python users.
+
+* :ref:`reference-index`: A detailed explanation of Python's syntax and
+ semantics. It's heavy reading, but is useful as a complete guide to the
+ language itself.
+
+More Python resources:
+
+* http://www.python.org: The major Python Web site. It contains code,
+ documentation, and pointers to Python-related pages around the Web. This Web
+ site is mirrored in various places around the world, such as Europe, Japan, and
+ Australia; a mirror may be faster than the main site, depending on your
+ geographical location.
+
+* http://docs.python.org: Fast access to Python's documentation.
+
+* http://cheeseshop.python.org: The Python Package Index, nicknamed the Cheese
+ Shop, is an index of user-created Python modules that are available for
+ download. Once you begin releasing code, you can register it here so that
+ others can find it.
+
+* http://aspn.activestate.com/ASPN/Python/Cookbook/: The Python Cookbook is a
+ sizable collection of code examples, larger modules, and useful scripts.
+ Particularly notable contributions are collected in a book also titled Python
+ Cookbook (O'Reilly & Associates, ISBN 0-596-00797-3.)
+
+For Python-related questions and problem reports, you can post to the newsgroup
+:newsgroup:`comp.lang.python`, or send them to the mailing list at
+python-list@python.org. The newsgroup and mailing list are gatewayed, so
+messages posted to one will automatically be forwarded to the other. There are
+around 120 postings a day (with peaks up to several hundred), asking (and
+answering) questions, suggesting new features, and announcing new modules.
+Before posting, be sure to check the list of `Frequently Asked Questions
+<http://www.python.org/doc/faq/>`_ (also called the FAQ), or look for it in the
+:file:`Misc/` directory of the Python source distribution. Mailing list
+archives are available at http://mail.python.org/pipermail/. The FAQ answers
+many of the questions that come up again and again, and may already contain the
+solution for your problem.
+
+.. % Postings figure based on average of last six months activity as
+.. % reported by www.egroups.com; Jan. 2000 - June 2000: 21272 msgs / 182
+.. % days = 116.9 msgs / day and steadily increasing.
+
+
diff --git a/Doc/whatsnew/2.0.rst b/Doc/whatsnew/2.0.rst
new file mode 100644
index 0000000000..302986c163
--- /dev/null
+++ b/Doc/whatsnew/2.0.rst
@@ -0,0 +1,1207 @@
+****************************
+ What's New in Python 2.0
+****************************
+
+:Author: A.M. Kuchling and Moshe Zadka
+
+.. |release| replace:: 1.02
+
+.. % $Id: whatsnew20.tex 51211 2006-08-11 14:57:12Z thomas.wouters $
+
+
+Introduction
+============
+
+A new release of Python, version 2.0, was released on October 16, 2000. This
+article covers the exciting new features in 2.0, highlights some other useful
+changes, and points out a few incompatible changes that may require rewriting
+code.
+
+Python's development never completely stops between releases, and a steady flow
+of bug fixes and improvements are always being submitted. A host of minor fixes,
+a few optimizations, additional docstrings, and better error messages went into
+2.0; to list them all would be impossible, but they're certainly significant.
+Consult the publicly-available CVS logs if you want to see the full list. This
+progress is due to the five developers working for PythonLabs are now getting
+paid to spend their days fixing bugs, and also due to the improved communication
+resulting from moving to SourceForge.
+
+.. % ======================================================================
+
+
+What About Python 1.6?
+======================
+
+Python 1.6 can be thought of as the Contractual Obligations Python release.
+After the core development team left CNRI in May 2000, CNRI requested that a 1.6
+release be created, containing all the work on Python that had been performed at
+CNRI. Python 1.6 therefore represents the state of the CVS tree as of May 2000,
+with the most significant new feature being Unicode support. Development
+continued after May, of course, so the 1.6 tree received a few fixes to ensure
+that it's forward-compatible with Python 2.0. 1.6 is therefore part of Python's
+evolution, and not a side branch.
+
+So, should you take much interest in Python 1.6? Probably not. The 1.6final
+and 2.0beta1 releases were made on the same day (September 5, 2000), the plan
+being to finalize Python 2.0 within a month or so. If you have applications to
+maintain, there seems little point in breaking things by moving to 1.6, fixing
+them, and then having another round of breakage within a month by moving to 2.0;
+you're better off just going straight to 2.0. Most of the really interesting
+features described in this document are only in 2.0, because a lot of work was
+done between May and September.
+
+.. % ======================================================================
+
+
+New Development Process
+=======================
+
+The most important change in Python 2.0 may not be to the code at all, but to
+how Python is developed: in May 2000 the Python developers began using the tools
+made available by SourceForge for storing source code, tracking bug reports,
+and managing the queue of patch submissions. To report bugs or submit patches
+for Python 2.0, use the bug tracking and patch manager tools available from
+Python's project page, located at http://sourceforge.net/projects/python/.
+
+The most important of the services now hosted at SourceForge is the Python CVS
+tree, the version-controlled repository containing the source code for Python.
+Previously, there were roughly 7 or so people who had write access to the CVS
+tree, and all patches had to be inspected and checked in by one of the people on
+this short list. Obviously, this wasn't very scalable. By moving the CVS tree
+to SourceForge, it became possible to grant write access to more people; as of
+September 2000 there were 27 people able to check in changes, a fourfold
+increase. This makes possible large-scale changes that wouldn't be attempted if
+they'd have to be filtered through the small group of core developers. For
+example, one day Peter Schneider-Kamp took it into his head to drop K&R C
+compatibility and convert the C source for Python to ANSI C. After getting
+approval on the python-dev mailing list, he launched into a flurry of checkins
+that lasted about a week, other developers joined in to help, and the job was
+done. If there were only 5 people with write access, probably that task would
+have been viewed as "nice, but not worth the time and effort needed" and it
+would never have gotten done.
+
+The shift to using SourceForge's services has resulted in a remarkable increase
+in the speed of development. Patches now get submitted, commented on, revised
+by people other than the original submitter, and bounced back and forth between
+people until the patch is deemed worth checking in. Bugs are tracked in one
+central location and can be assigned to a specific person for fixing, and we can
+count the number of open bugs to measure progress. This didn't come without a
+cost: developers now have more e-mail to deal with, more mailing lists to
+follow, and special tools had to be written for the new environment. For
+example, SourceForge sends default patch and bug notification e-mail messages
+that are completely unhelpful, so Ka-Ping Yee wrote an HTML screen-scraper that
+sends more useful messages.
+
+The ease of adding code caused a few initial growing pains, such as code was
+checked in before it was ready or without getting clear agreement from the
+developer group. The approval process that has emerged is somewhat similar to
+that used by the Apache group. Developers can vote +1, +0, -0, or -1 on a patch;
++1 and -1 denote acceptance or rejection, while +0 and -0 mean the developer is
+mostly indifferent to the change, though with a slight positive or negative
+slant. The most significant change from the Apache model is that the voting is
+essentially advisory, letting Guido van Rossum, who has Benevolent Dictator For
+Life status, know what the general opinion is. He can still ignore the result of
+a vote, and approve or reject a change even if the community disagrees with him.
+
+Producing an actual patch is the last step in adding a new feature, and is
+usually easy compared to the earlier task of coming up with a good design.
+Discussions of new features can often explode into lengthy mailing list threads,
+making the discussion hard to follow, and no one can read every posting to
+python-dev. Therefore, a relatively formal process has been set up to write
+Python Enhancement Proposals (PEPs), modelled on the Internet RFC process. PEPs
+are draft documents that describe a proposed new feature, and are continually
+revised until the community reaches a consensus, either accepting or rejecting
+the proposal. Quoting from the introduction to PEP 1, "PEP Purpose and
+Guidelines":
+
+
+.. epigraph::
+
+ PEP stands for Python Enhancement Proposal. A PEP is a design document
+ providing information to the Python community, or describing a new feature for
+ Python. The PEP should provide a concise technical specification of the feature
+ and a rationale for the feature.
+
+ We intend PEPs to be the primary mechanisms for proposing new features, for
+ collecting community input on an issue, and for documenting the design decisions
+ that have gone into Python. The PEP author is responsible for building
+ consensus within the community and documenting dissenting opinions.
+
+Read the rest of PEP 1 for the details of the PEP editorial process, style, and
+format. PEPs are kept in the Python CVS tree on SourceForge, though they're not
+part of the Python 2.0 distribution, and are also available in HTML form from
+http://www.python.org/peps/. As of September 2000, there are 25 PEPS, ranging
+from PEP 201, "Lockstep Iteration", to PEP 225, "Elementwise/Objectwise
+Operators".
+
+.. % ======================================================================
+
+
+Unicode
+=======
+
+The largest new feature in Python 2.0 is a new fundamental data type: Unicode
+strings. Unicode uses 16-bit numbers to represent characters instead of the
+8-bit number used by ASCII, meaning that 65,536 distinct characters can be
+supported.
+
+The final interface for Unicode support was arrived at through countless often-
+stormy discussions on the python-dev mailing list, and mostly implemented by
+Marc-André Lemburg, based on a Unicode string type implementation by Fredrik
+Lundh. A detailed explanation of the interface was written up as :pep:`100`,
+"Python Unicode Integration". This article will simply cover the most
+significant points about the Unicode interfaces.
+
+In Python source code, Unicode strings are written as ``u"string"``. Arbitrary
+Unicode characters can be written using a new escape sequence, ``\uHHHH``, where
+*HHHH* is a 4-digit hexadecimal number from 0000 to FFFF. The existing
+``\xHHHH`` escape sequence can also be used, and octal escapes can be used for
+characters up to U+01FF, which is represented by ``\777``.
+
+Unicode strings, just like regular strings, are an immutable sequence type.
+They can be indexed and sliced, but not modified in place. Unicode strings have
+an ``encode( [encoding] )`` method that returns an 8-bit string in the desired
+encoding. Encodings are named by strings, such as ``'ascii'``, ``'utf-8'``,
+``'iso-8859-1'``, or whatever. A codec API is defined for implementing and
+registering new encodings that are then available throughout a Python program.
+If an encoding isn't specified, the default encoding is usually 7-bit ASCII,
+though it can be changed for your Python installation by calling the
+:func:`sys.setdefaultencoding(encoding)` function in a customised version of
+:file:`site.py`.
+
+Combining 8-bit and Unicode strings always coerces to Unicode, using the default
+ASCII encoding; the result of ``'a' + u'bc'`` is ``u'abc'``.
+
+New built-in functions have been added, and existing built-ins modified to
+support Unicode:
+
+* ``unichr(ch)`` returns a Unicode string 1 character long, containing the
+ character *ch*.
+
+* ``ord(u)``, where *u* is a 1-character regular or Unicode string, returns the
+ number of the character as an integer.
+
+* ``unicode(string [, encoding] [, errors] )`` creates a Unicode string
+ from an 8-bit string. ``encoding`` is a string naming the encoding to use. The
+ ``errors`` parameter specifies the treatment of characters that are invalid for
+ the current encoding; passing ``'strict'`` as the value causes an exception to
+ be raised on any encoding error, while ``'ignore'`` causes errors to be silently
+ ignored and ``'replace'`` uses U+FFFD, the official replacement character, in
+ case of any problems.
+
+* The :keyword:`exec` statement, and various built-ins such as ``eval()``,
+ ``getattr()``, and ``setattr()`` will also accept Unicode strings as well as
+ regular strings. (It's possible that the process of fixing this missed some
+ built-ins; if you find a built-in function that accepts strings but doesn't
+ accept Unicode strings at all, please report it as a bug.)
+
+A new module, :mod:`unicodedata`, provides an interface to Unicode character
+properties. For example, ``unicodedata.category(u'A')`` returns the 2-character
+string 'Lu', the 'L' denoting it's a letter, and 'u' meaning that it's
+uppercase. ``unicodedata.bidirectional(u'\u0660')`` returns 'AN', meaning that
+U+0660 is an Arabic number.
+
+The :mod:`codecs` module contains functions to look up existing encodings and
+register new ones. Unless you want to implement a new encoding, you'll most
+often use the :func:`codecs.lookup(encoding)` function, which returns a
+4-element tuple: ``(encode_func, decode_func, stream_reader, stream_writer)``.
+
+* *encode_func* is a function that takes a Unicode string, and returns a 2-tuple
+ ``(string, length)``. *string* is an 8-bit string containing a portion (perhaps
+ all) of the Unicode string converted into the given encoding, and *length* tells
+ you how much of the Unicode string was converted.
+
+* *decode_func* is the opposite of *encode_func*, taking an 8-bit string and
+ returning a 2-tuple ``(ustring, length)``, consisting of the resulting Unicode
+ string *ustring* and the integer *length* telling how much of the 8-bit string
+ was consumed.
+
+* *stream_reader* is a class that supports decoding input from a stream.
+ *stream_reader(file_obj)* returns an object that supports the :meth:`read`,
+ :meth:`readline`, and :meth:`readlines` methods. These methods will all
+ translate from the given encoding and return Unicode strings.
+
+* *stream_writer*, similarly, is a class that supports encoding output to a
+ stream. *stream_writer(file_obj)* returns an object that supports the
+ :meth:`write` and :meth:`writelines` methods. These methods expect Unicode
+ strings, translating them to the given encoding on output.
+
+For example, the following code writes a Unicode string into a file, encoding
+it as UTF-8::
+
+ import codecs
+
+ unistr = u'\u0660\u2000ab ...'
+
+ (UTF8_encode, UTF8_decode,
+ UTF8_streamreader, UTF8_streamwriter) = codecs.lookup('UTF-8')
+
+ output = UTF8_streamwriter( open( '/tmp/output', 'wb') )
+ output.write( unistr )
+ output.close()
+
+The following code would then read UTF-8 input from the file::
+
+ input = UTF8_streamreader( open( '/tmp/output', 'rb') )
+ print repr(input.read())
+ input.close()
+
+Unicode-aware regular expressions are available through the :mod:`re` module,
+which has a new underlying implementation called SRE written by Fredrik Lundh of
+Secret Labs AB.
+
+A ``-U`` command line option was added which causes the Python compiler to
+interpret all string literals as Unicode string literals. This is intended to be
+used in testing and future-proofing your Python code, since some future version
+of Python may drop support for 8-bit strings and provide only Unicode strings.
+
+.. % ======================================================================
+
+
+List Comprehensions
+===================
+
+Lists are a workhorse data type in Python, and many programs manipulate a list
+at some point. Two common operations on lists are to loop over them, and either
+pick out the elements that meet a certain criterion, or apply some function to
+each element. For example, given a list of strings, you might want to pull out
+all the strings containing a given substring, or strip off trailing whitespace
+from each line.
+
+The existing :func:`map` and :func:`filter` functions can be used for this
+purpose, but they require a function as one of their arguments. This is fine if
+there's an existing built-in function that can be passed directly, but if there
+isn't, you have to create a little function to do the required work, and
+Python's scoping rules make the result ugly if the little function needs
+additional information. Take the first example in the previous paragraph,
+finding all the strings in the list containing a given substring. You could
+write the following to do it::
+
+ # Given the list L, make a list of all strings
+ # containing the substring S.
+ sublist = filter( lambda s, substring=S:
+ string.find(s, substring) != -1,
+ L)
+
+Because of Python's scoping rules, a default argument is used so that the
+anonymous function created by the :keyword:`lambda` statement knows what
+substring is being searched for. List comprehensions make this cleaner::
+
+ sublist = [ s for s in L if string.find(s, S) != -1 ]
+
+List comprehensions have the form::
+
+ [ expression for expr in sequence1
+ for expr2 in sequence2 ...
+ for exprN in sequenceN
+ if condition ]
+
+The :keyword:`for`...\ :keyword:`in` clauses contain the sequences to be
+iterated over. The sequences do not have to be the same length, because they
+are *not* iterated over in parallel, but from left to right; this is explained
+more clearly in the following paragraphs. The elements of the generated list
+will be the successive values of *expression*. The final :keyword:`if` clause
+is optional; if present, *expression* is only evaluated and added to the result
+if *condition* is true.
+
+To make the semantics very clear, a list comprehension is equivalent to the
+following Python code::
+
+ for expr1 in sequence1:
+ for expr2 in sequence2:
+ ...
+ for exprN in sequenceN:
+ if (condition):
+ # Append the value of
+ # the expression to the
+ # resulting list.
+
+This means that when there are multiple :keyword:`for`...\ :keyword:`in`
+clauses, the resulting list will be equal to the product of the lengths of all
+the sequences. If you have two lists of length 3, the output list is 9 elements
+long::
+
+ seq1 = 'abc'
+ seq2 = (1,2,3)
+ >>> [ (x,y) for x in seq1 for y in seq2]
+ [('a', 1), ('a', 2), ('a', 3), ('b', 1), ('b', 2), ('b', 3), ('c', 1),
+ ('c', 2), ('c', 3)]
+
+To avoid introducing an ambiguity into Python's grammar, if *expression* is
+creating a tuple, it must be surrounded with parentheses. The first list
+comprehension below is a syntax error, while the second one is correct::
+
+ # Syntax error
+ [ x,y for x in seq1 for y in seq2]
+ # Correct
+ [ (x,y) for x in seq1 for y in seq2]
+
+The idea of list comprehensions originally comes from the functional programming
+language Haskell (http://www.haskell.org). Greg Ewing argued most effectively
+for adding them to Python and wrote the initial list comprehension patch, which
+was then discussed for a seemingly endless time on the python-dev mailing list
+and kept up-to-date by Skip Montanaro.
+
+.. % ======================================================================
+
+
+Augmented Assignment
+====================
+
+Augmented assignment operators, another long-requested feature, have been added
+to Python 2.0. Augmented assignment operators include ``+=``, ``-=``, ``*=``,
+and so forth. For example, the statement ``a += 2`` increments the value of the
+variable ``a`` by 2, equivalent to the slightly lengthier ``a = a + 2``.
+
+The full list of supported assignment operators is ``+=``, ``-=``, ``*=``,
+``/=``, ``%=``, ``**=``, ``&=``, ``|=``, ``^=``, ``>>=``, and ``<<=``. Python
+classes can override the augmented assignment operators by defining methods
+named :meth:`__iadd__`, :meth:`__isub__`, etc. For example, the following
+:class:`Number` class stores a number and supports using += to create a new
+instance with an incremented value.
+
+.. % The empty groups below prevent conversion to guillemets.
+
+::
+
+ class Number:
+ def __init__(self, value):
+ self.value = value
+ def __iadd__(self, increment):
+ return Number( self.value + increment)
+
+ n = Number(5)
+ n += 3
+ print n.value
+
+The :meth:`__iadd__` special method is called with the value of the increment,
+and should return a new instance with an appropriately modified value; this
+return value is bound as the new value of the variable on the left-hand side.
+
+Augmented assignment operators were first introduced in the C programming
+language, and most C-derived languages, such as :program:`awk`, C++, Java, Perl,
+and PHP also support them. The augmented assignment patch was implemented by
+Thomas Wouters.
+
+.. % ======================================================================
+
+
+String Methods
+==============
+
+Until now string-manipulation functionality was in the :mod:`string` module,
+which was usually a front-end for the :mod:`strop` module written in C. The
+addition of Unicode posed a difficulty for the :mod:`strop` module, because the
+functions would all need to be rewritten in order to accept either 8-bit or
+Unicode strings. For functions such as :func:`string.replace`, which takes 3
+string arguments, that means eight possible permutations, and correspondingly
+complicated code.
+
+Instead, Python 2.0 pushes the problem onto the string type, making string
+manipulation functionality available through methods on both 8-bit strings and
+Unicode strings. ::
+
+ >>> 'andrew'.capitalize()
+ 'Andrew'
+ >>> 'hostname'.replace('os', 'linux')
+ 'hlinuxtname'
+ >>> 'moshe'.find('sh')
+ 2
+
+One thing that hasn't changed, a noteworthy April Fools' joke notwithstanding,
+is that Python strings are immutable. Thus, the string methods return new
+strings, and do not modify the string on which they operate.
+
+The old :mod:`string` module is still around for backwards compatibility, but it
+mostly acts as a front-end to the new string methods.
+
+Two methods which have no parallel in pre-2.0 versions, although they did exist
+in JPython for quite some time, are :meth:`startswith` and :meth:`endswith`.
+``s.startswith(t)`` is equivalent to ``s[:len(t)] == t``, while
+``s.endswith(t)`` is equivalent to ``s[-len(t):] == t``.
+
+One other method which deserves special mention is :meth:`join`. The
+:meth:`join` method of a string receives one parameter, a sequence of strings,
+and is equivalent to the :func:`string.join` function from the old :mod:`string`
+module, with the arguments reversed. In other words, ``s.join(seq)`` is
+equivalent to the old ``string.join(seq, s)``.
+
+.. % ======================================================================
+
+
+Garbage Collection of Cycles
+============================
+
+The C implementation of Python uses reference counting to implement garbage
+collection. Every Python object maintains a count of the number of references
+pointing to itself, and adjusts the count as references are created or
+destroyed. Once the reference count reaches zero, the object is no longer
+accessible, since you need to have a reference to an object to access it, and if
+the count is zero, no references exist any longer.
+
+Reference counting has some pleasant properties: it's easy to understand and
+implement, and the resulting implementation is portable, fairly fast, and reacts
+well with other libraries that implement their own memory handling schemes. The
+major problem with reference counting is that it sometimes doesn't realise that
+objects are no longer accessible, resulting in a memory leak. This happens when
+there are cycles of references.
+
+Consider the simplest possible cycle, a class instance which has a reference to
+itself::
+
+ instance = SomeClass()
+ instance.myself = instance
+
+After the above two lines of code have been executed, the reference count of
+``instance`` is 2; one reference is from the variable named ``'instance'``, and
+the other is from the ``myself`` attribute of the instance.
+
+If the next line of code is ``del instance``, what happens? The reference count
+of ``instance`` is decreased by 1, so it has a reference count of 1; the
+reference in the ``myself`` attribute still exists. Yet the instance is no
+longer accessible through Python code, and it could be deleted. Several objects
+can participate in a cycle if they have references to each other, causing all of
+the objects to be leaked.
+
+Python 2.0 fixes this problem by periodically executing a cycle detection
+algorithm which looks for inaccessible cycles and deletes the objects involved.
+A new :mod:`gc` module provides functions to perform a garbage collection,
+obtain debugging statistics, and tuning the collector's parameters.
+
+Running the cycle detection algorithm takes some time, and therefore will result
+in some additional overhead. It is hoped that after we've gotten experience
+with the cycle collection from using 2.0, Python 2.1 will be able to minimize
+the overhead with careful tuning. It's not yet obvious how much performance is
+lost, because benchmarking this is tricky and depends crucially on how often the
+program creates and destroys objects. The detection of cycles can be disabled
+when Python is compiled, if you can't afford even a tiny speed penalty or
+suspect that the cycle collection is buggy, by specifying the
+:option:`--without-cycle-gc` switch when running the :program:`configure`
+script.
+
+Several people tackled this problem and contributed to a solution. An early
+implementation of the cycle detection approach was written by Toby Kelsey. The
+current algorithm was suggested by Eric Tiedemann during a visit to CNRI, and
+Guido van Rossum and Neil Schemenauer wrote two different implementations, which
+were later integrated by Neil. Lots of other people offered suggestions along
+the way; the March 2000 archives of the python-dev mailing list contain most of
+the relevant discussion, especially in the threads titled "Reference cycle
+collection for Python" and "Finalization again".
+
+.. % ======================================================================
+
+
+Other Core Changes
+==================
+
+Various minor changes have been made to Python's syntax and built-in functions.
+None of the changes are very far-reaching, but they're handy conveniences.
+
+
+Minor Language Changes
+----------------------
+
+A new syntax makes it more convenient to call a given function with a tuple of
+arguments and/or a dictionary of keyword arguments. In Python 1.5 and earlier,
+you'd use the :func:`apply` built-in function: ``apply(f, args, kw)`` calls the
+function :func:`f` with the argument tuple *args* and the keyword arguments in
+the dictionary *kw*. :func:`apply` is the same in 2.0, but thanks to a patch
+from Greg Ewing, ``f(*args, **kw)`` as a shorter and clearer way to achieve the
+same effect. This syntax is symmetrical with the syntax for defining
+functions::
+
+ def f(*args, **kw):
+ # args is a tuple of positional args,
+ # kw is a dictionary of keyword args
+ ...
+
+The :keyword:`print` statement can now have its output directed to a file-like
+object by following the :keyword:`print` with ``>> file``, similar to the
+redirection operator in Unix shells. Previously you'd either have to use the
+:meth:`write` method of the file-like object, which lacks the convenience and
+simplicity of :keyword:`print`, or you could assign a new value to
+``sys.stdout`` and then restore the old value. For sending output to standard
+error, it's much easier to write this::
+
+ print >> sys.stderr, "Warning: action field not supplied"
+
+Modules can now be renamed on importing them, using the syntax ``import module
+as name`` or ``from module import name as othername``. The patch was submitted
+by Thomas Wouters.
+
+A new format style is available when using the ``%`` operator; '%r' will insert
+the :func:`repr` of its argument. This was also added from symmetry
+considerations, this time for symmetry with the existing '%s' format style,
+which inserts the :func:`str` of its argument. For example, ``'%r %s' % ('abc',
+'abc')`` returns a string containing ``'abc' abc``.
+
+Previously there was no way to implement a class that overrode Python's built-in
+:keyword:`in` operator and implemented a custom version. ``obj in seq`` returns
+true if *obj* is present in the sequence *seq*; Python computes this by simply
+trying every index of the sequence until either *obj* is found or an
+:exc:`IndexError` is encountered. Moshe Zadka contributed a patch which adds a
+:meth:`__contains__` magic method for providing a custom implementation for
+:keyword:`in`. Additionally, new built-in objects written in C can define what
+:keyword:`in` means for them via a new slot in the sequence protocol.
+
+Earlier versions of Python used a recursive algorithm for deleting objects.
+Deeply nested data structures could cause the interpreter to fill up the C stack
+and crash; Christian Tismer rewrote the deletion logic to fix this problem. On
+a related note, comparing recursive objects recursed infinitely and crashed;
+Jeremy Hylton rewrote the code to no longer crash, producing a useful result
+instead. For example, after this code::
+
+ a = []
+ b = []
+ a.append(a)
+ b.append(b)
+
+The comparison ``a==b`` returns true, because the two recursive data structures
+are isomorphic. See the thread "trashcan and PR#7" in the April 2000 archives of
+the python-dev mailing list for the discussion leading up to this
+implementation, and some useful relevant links. Note that comparisons can now
+also raise exceptions. In earlier versions of Python, a comparison operation
+such as ``cmp(a,b)`` would always produce an answer, even if a user-defined
+:meth:`__cmp__` method encountered an error, since the resulting exception would
+simply be silently swallowed.
+
+.. % Starting URL:
+.. % http://www.python.org/pipermail/python-dev/2000-April/004834.html
+
+Work has been done on porting Python to 64-bit Windows on the Itanium processor,
+mostly by Trent Mick of ActiveState. (Confusingly, ``sys.platform`` is still
+``'win32'`` on Win64 because it seems that for ease of porting, MS Visual C++
+treats code as 32 bit on Itanium.) PythonWin also supports Windows CE; see the
+Python CE page at http://starship.python.net/crew/mhammond/ce/ for more
+information.
+
+Another new platform is Darwin/MacOS X; initial support for it is in Python 2.0.
+Dynamic loading works, if you specify "configure --with-dyld --with-suffix=.x".
+Consult the README in the Python source distribution for more instructions.
+
+An attempt has been made to alleviate one of Python's warts, the often-confusing
+:exc:`NameError` exception when code refers to a local variable before the
+variable has been assigned a value. For example, the following code raises an
+exception on the :keyword:`print` statement in both 1.5.2 and 2.0; in 1.5.2 a
+:exc:`NameError` exception is raised, while 2.0 raises a new
+:exc:`UnboundLocalError` exception. :exc:`UnboundLocalError` is a subclass of
+:exc:`NameError`, so any existing code that expects :exc:`NameError` to be
+raised should still work. ::
+
+ def f():
+ print "i=",i
+ i = i + 1
+ f()
+
+Two new exceptions, :exc:`TabError` and :exc:`IndentationError`, have been
+introduced. They're both subclasses of :exc:`SyntaxError`, and are raised when
+Python code is found to be improperly indented.
+
+
+Changes to Built-in Functions
+-----------------------------
+
+A new built-in, :func:`zip(seq1, seq2, ...)`, has been added. :func:`zip`
+returns a list of tuples where each tuple contains the i-th element from each of
+the argument sequences. The difference between :func:`zip` and ``map(None,
+seq1, seq2)`` is that :func:`map` pads the sequences with ``None`` if the
+sequences aren't all of the same length, while :func:`zip` truncates the
+returned list to the length of the shortest argument sequence.
+
+The :func:`int` and :func:`long` functions now accept an optional "base"
+parameter when the first argument is a string. ``int('123', 10)`` returns 123,
+while ``int('123', 16)`` returns 291. ``int(123, 16)`` raises a
+:exc:`TypeError` exception with the message "can't convert non-string with
+explicit base".
+
+A new variable holding more detailed version information has been added to the
+:mod:`sys` module. ``sys.version_info`` is a tuple ``(major, minor, micro,
+level, serial)`` For example, in a hypothetical 2.0.1beta1, ``sys.version_info``
+would be ``(2, 0, 1, 'beta', 1)``. *level* is a string such as ``"alpha"``,
+``"beta"``, or ``"final"`` for a final release.
+
+Dictionaries have an odd new method, :meth:`setdefault(key, default)`, which
+behaves similarly to the existing :meth:`get` method. However, if the key is
+missing, :meth:`setdefault` both returns the value of *default* as :meth:`get`
+would do, and also inserts it into the dictionary as the value for *key*. Thus,
+the following lines of code::
+
+ if dict.has_key( key ): return dict[key]
+ else:
+ dict[key] = []
+ return dict[key]
+
+can be reduced to a single ``return dict.setdefault(key, [])`` statement.
+
+The interpreter sets a maximum recursion depth in order to catch runaway
+recursion before filling the C stack and causing a core dump or GPF..
+Previously this limit was fixed when you compiled Python, but in 2.0 the maximum
+recursion depth can be read and modified using :func:`sys.getrecursionlimit` and
+:func:`sys.setrecursionlimit`. The default value is 1000, and a rough maximum
+value for a given platform can be found by running a new script,
+:file:`Misc/find_recursionlimit.py`.
+
+.. % ======================================================================
+
+
+Porting to 2.0
+==============
+
+New Python releases try hard to be compatible with previous releases, and the
+record has been pretty good. However, some changes are considered useful
+enough, usually because they fix initial design decisions that turned out to be
+actively mistaken, that breaking backward compatibility can't always be avoided.
+This section lists the changes in Python 2.0 that may cause old Python code to
+break.
+
+The change which will probably break the most code is tightening up the
+arguments accepted by some methods. Some methods would take multiple arguments
+and treat them as a tuple, particularly various list methods such as
+:meth:`.append` and :meth:`.insert`. In earlier versions of Python, if ``L`` is
+a list, ``L.append( 1,2 )`` appends the tuple ``(1,2)`` to the list. In Python
+2.0 this causes a :exc:`TypeError` exception to be raised, with the message:
+'append requires exactly 1 argument; 2 given'. The fix is to simply add an
+extra set of parentheses to pass both values as a tuple: ``L.append( (1,2) )``.
+
+The earlier versions of these methods were more forgiving because they used an
+old function in Python's C interface to parse their arguments; 2.0 modernizes
+them to use :func:`PyArg_ParseTuple`, the current argument parsing function,
+which provides more helpful error messages and treats multi-argument calls as
+errors. If you absolutely must use 2.0 but can't fix your code, you can edit
+:file:`Objects/listobject.c` and define the preprocessor symbol
+``NO_STRICT_LIST_APPEND`` to preserve the old behaviour; this isn't recommended.
+
+Some of the functions in the :mod:`socket` module are still forgiving in this
+way. For example, :func:`socket.connect( ('hostname', 25) )` is the correct
+form, passing a tuple representing an IP address, but :func:`socket.connect(
+'hostname', 25 )` also works. :func:`socket.connect_ex` and :func:`socket.bind`
+are similarly easy-going. 2.0alpha1 tightened these functions up, but because
+the documentation actually used the erroneous multiple argument form, many
+people wrote code which would break with the stricter checking. GvR backed out
+the changes in the face of public reaction, so for the :mod:`socket` module, the
+documentation was fixed and the multiple argument form is simply marked as
+deprecated; it *will* be tightened up again in a future Python version.
+
+The ``\x`` escape in string literals now takes exactly 2 hex digits. Previously
+it would consume all the hex digits following the 'x' and take the lowest 8 bits
+of the result, so ``\x123456`` was equivalent to ``\x56``.
+
+The :exc:`AttributeError` and :exc:`NameError` exceptions have a more friendly
+error message, whose text will be something like ``'Spam' instance has no
+attribute 'eggs'`` or ``name 'eggs' is not defined``. Previously the error
+message was just the missing attribute name ``eggs``, and code written to take
+advantage of this fact will break in 2.0.
+
+Some work has been done to make integers and long integers a bit more
+interchangeable. In 1.5.2, large-file support was added for Solaris, to allow
+reading files larger than 2 GiB; this made the :meth:`tell` method of file
+objects return a long integer instead of a regular integer. Some code would
+subtract two file offsets and attempt to use the result to multiply a sequence
+or slice a string, but this raised a :exc:`TypeError`. In 2.0, long integers
+can be used to multiply or slice a sequence, and it'll behave as you'd
+intuitively expect it to; ``3L * 'abc'`` produces 'abcabcabc', and
+``(0,1,2,3)[2L:4L]`` produces (2,3). Long integers can also be used in various
+contexts where previously only integers were accepted, such as in the
+:meth:`seek` method of file objects, and in the formats supported by the ``%``
+operator (``%d``, ``%i``, ``%x``, etc.). For example, ``"%d" % 2L**64`` will
+produce the string ``18446744073709551616``.
+
+The subtlest long integer change of all is that the :func:`str` of a long
+integer no longer has a trailing 'L' character, though :func:`repr` still
+includes it. The 'L' annoyed many people who wanted to print long integers that
+looked just like regular integers, since they had to go out of their way to chop
+off the character. This is no longer a problem in 2.0, but code which does
+``str(longval)[:-1]`` and assumes the 'L' is there, will now lose the final
+digit.
+
+Taking the :func:`repr` of a float now uses a different formatting precision
+than :func:`str`. :func:`repr` uses ``%.17g`` format string for C's
+:func:`sprintf`, while :func:`str` uses ``%.12g`` as before. The effect is that
+:func:`repr` may occasionally show more decimal places than :func:`str`, for
+certain numbers. For example, the number 8.1 can't be represented exactly in
+binary, so ``repr(8.1)`` is ``'8.0999999999999996'``, while str(8.1) is
+``'8.1'``.
+
+The ``-X`` command-line option, which turned all standard exceptions into
+strings instead of classes, has been removed; the standard exceptions will now
+always be classes. The :mod:`exceptions` module containing the standard
+exceptions was translated from Python to a built-in C module, written by Barry
+Warsaw and Fredrik Lundh.
+
+.. % Commented out for now -- I don't think anyone will care.
+.. % The pattern and match objects provided by SRE are C types, not Python
+.. % class instances as in 1.5. This means you can no longer inherit from
+.. % \class{RegexObject} or \class{MatchObject}, but that shouldn't be much
+.. % of a problem since no one should have been doing that in the first
+.. % place.
+.. % ======================================================================
+
+
+Extending/Embedding Changes
+===========================
+
+Some of the changes are under the covers, and will only be apparent to people
+writing C extension modules or embedding a Python interpreter in a larger
+application. If you aren't dealing with Python's C API, you can safely skip
+this section.
+
+The version number of the Python C API was incremented, so C extensions compiled
+for 1.5.2 must be recompiled in order to work with 2.0. On Windows, it's not
+possible for Python 2.0 to import a third party extension built for Python 1.5.x
+due to how Windows DLLs work, so Python will raise an exception and the import
+will fail.
+
+Users of Jim Fulton's ExtensionClass module will be pleased to find out that
+hooks have been added so that ExtensionClasses are now supported by
+:func:`isinstance` and :func:`issubclass`. This means you no longer have to
+remember to write code such as ``if type(obj) == myExtensionClass``, but can use
+the more natural ``if isinstance(obj, myExtensionClass)``.
+
+The :file:`Python/importdl.c` file, which was a mass of #ifdefs to support
+dynamic loading on many different platforms, was cleaned up and reorganised by
+Greg Stein. :file:`importdl.c` is now quite small, and platform-specific code
+has been moved into a bunch of :file:`Python/dynload_\*.c` files. Another
+cleanup: there were also a number of :file:`my\*.h` files in the Include/
+directory that held various portability hacks; they've been merged into a single
+file, :file:`Include/pyport.h`.
+
+Vladimir Marangozov's long-awaited malloc restructuring was completed, to make
+it easy to have the Python interpreter use a custom allocator instead of C's
+standard :func:`malloc`. For documentation, read the comments in
+:file:`Include/pymem.h` and :file:`Include/objimpl.h`. For the lengthy
+discussions during which the interface was hammered out, see the Web archives of
+the 'patches' and 'python-dev' lists at python.org.
+
+Recent versions of the GUSI development environment for MacOS support POSIX
+threads. Therefore, Python's POSIX threading support now works on the
+Macintosh. Threading support using the user-space GNU ``pth`` library was also
+contributed.
+
+Threading support on Windows was enhanced, too. Windows supports thread locks
+that use kernel objects only in case of contention; in the common case when
+there's no contention, they use simpler functions which are an order of
+magnitude faster. A threaded version of Python 1.5.2 on NT is twice as slow as
+an unthreaded version; with the 2.0 changes, the difference is only 10%. These
+improvements were contributed by Yakov Markovitch.
+
+Python 2.0's source now uses only ANSI C prototypes, so compiling Python now
+requires an ANSI C compiler, and can no longer be done using a compiler that
+only supports K&R C.
+
+Previously the Python virtual machine used 16-bit numbers in its bytecode,
+limiting the size of source files. In particular, this affected the maximum
+size of literal lists and dictionaries in Python source; occasionally people who
+are generating Python code would run into this limit. A patch by Charles G.
+Waldman raises the limit from ``2^16`` to ``2^{32}``.
+
+Three new convenience functions intended for adding constants to a module's
+dictionary at module initialization time were added: :func:`PyModule_AddObject`,
+:func:`PyModule_AddIntConstant`, and :func:`PyModule_AddStringConstant`. Each
+of these functions takes a module object, a null-terminated C string containing
+the name to be added, and a third argument for the value to be assigned to the
+name. This third argument is, respectively, a Python object, a C long, or a C
+string.
+
+A wrapper API was added for Unix-style signal handlers. :func:`PyOS_getsig` gets
+a signal handler and :func:`PyOS_setsig` will set a new handler.
+
+.. % ======================================================================
+
+
+Distutils: Making Modules Easy to Install
+=========================================
+
+Before Python 2.0, installing modules was a tedious affair -- there was no way
+to figure out automatically where Python is installed, or what compiler options
+to use for extension modules. Software authors had to go through an arduous
+ritual of editing Makefiles and configuration files, which only really work on
+Unix and leave Windows and MacOS unsupported. Python users faced wildly
+differing installation instructions which varied between different extension
+packages, which made administering a Python installation something of a chore.
+
+The SIG for distribution utilities, shepherded by Greg Ward, has created the
+Distutils, a system to make package installation much easier. They form the
+:mod:`distutils` package, a new part of Python's standard library. In the best
+case, installing a Python module from source will require the same steps: first
+you simply mean unpack the tarball or zip archive, and the run "``python
+setup.py install``". The platform will be automatically detected, the compiler
+will be recognized, C extension modules will be compiled, and the distribution
+installed into the proper directory. Optional command-line arguments provide
+more control over the installation process, the distutils package offers many
+places to override defaults -- separating the build from the install, building
+or installing in non-default directories, and more.
+
+In order to use the Distutils, you need to write a :file:`setup.py` script. For
+the simple case, when the software contains only .py files, a minimal
+:file:`setup.py` can be just a few lines long::
+
+ from distutils.core import setup
+ setup (name = "foo", version = "1.0",
+ py_modules = ["module1", "module2"])
+
+The :file:`setup.py` file isn't much more complicated if the software consists
+of a few packages::
+
+ from distutils.core import setup
+ setup (name = "foo", version = "1.0",
+ packages = ["package", "package.subpackage"])
+
+A C extension can be the most complicated case; here's an example taken from
+the PyXML package::
+
+ from distutils.core import setup, Extension
+
+ expat_extension = Extension('xml.parsers.pyexpat',
+ define_macros = [('XML_NS', None)],
+ include_dirs = [ 'extensions/expat/xmltok',
+ 'extensions/expat/xmlparse' ],
+ sources = [ 'extensions/pyexpat.c',
+ 'extensions/expat/xmltok/xmltok.c',
+ 'extensions/expat/xmltok/xmlrole.c',
+ ]
+ )
+ setup (name = "PyXML", version = "0.5.4",
+ ext_modules =[ expat_extension ] )
+
+The Distutils can also take care of creating source and binary distributions.
+The "sdist" command, run by "``python setup.py sdist``', builds a source
+distribution such as :file:`foo-1.0.tar.gz`. Adding new commands isn't
+difficult, "bdist_rpm" and "bdist_wininst" commands have already been
+contributed to create an RPM distribution and a Windows installer for the
+software, respectively. Commands to create other distribution formats such as
+Debian packages and Solaris :file:`.pkg` files are in various stages of
+development.
+
+All this is documented in a new manual, *Distributing Python Modules*, that
+joins the basic set of Python documentation.
+
+.. % ======================================================================
+
+
+XML Modules
+===========
+
+Python 1.5.2 included a simple XML parser in the form of the :mod:`xmllib`
+module, contributed by Sjoerd Mullender. Since 1.5.2's release, two different
+interfaces for processing XML have become common: SAX2 (version 2 of the Simple
+API for XML) provides an event-driven interface with some similarities to
+:mod:`xmllib`, and the DOM (Document Object Model) provides a tree-based
+interface, transforming an XML document into a tree of nodes that can be
+traversed and modified. Python 2.0 includes a SAX2 interface and a stripped-
+down DOM interface as part of the :mod:`xml` package. Here we will give a brief
+overview of these new interfaces; consult the Python documentation or the source
+code for complete details. The Python XML SIG is also working on improved
+documentation.
+
+
+SAX2 Support
+------------
+
+SAX defines an event-driven interface for parsing XML. To use SAX, you must
+write a SAX handler class. Handler classes inherit from various classes
+provided by SAX, and override various methods that will then be called by the
+XML parser. For example, the :meth:`startElement` and :meth:`endElement`
+methods are called for every starting and end tag encountered by the parser, the
+:meth:`characters` method is called for every chunk of character data, and so
+forth.
+
+The advantage of the event-driven approach is that the whole document doesn't
+have to be resident in memory at any one time, which matters if you are
+processing really huge documents. However, writing the SAX handler class can
+get very complicated if you're trying to modify the document structure in some
+elaborate way.
+
+For example, this little example program defines a handler that prints a message
+for every starting and ending tag, and then parses the file :file:`hamlet.xml`
+using it::
+
+ from xml import sax
+
+ class SimpleHandler(sax.ContentHandler):
+ def startElement(self, name, attrs):
+ print 'Start of element:', name, attrs.keys()
+
+ def endElement(self, name):
+ print 'End of element:', name
+
+ # Create a parser object
+ parser = sax.make_parser()
+
+ # Tell it what handler to use
+ handler = SimpleHandler()
+ parser.setContentHandler( handler )
+
+ # Parse a file!
+ parser.parse( 'hamlet.xml' )
+
+For more information, consult the Python documentation, or the XML HOWTO at
+http://pyxml.sourceforge.net/topics/howto/xml-howto.html.
+
+
+DOM Support
+-----------
+
+The Document Object Model is a tree-based representation for an XML document. A
+top-level :class:`Document` instance is the root of the tree, and has a single
+child which is the top-level :class:`Element` instance. This :class:`Element`
+has children nodes representing character data and any sub-elements, which may
+have further children of their own, and so forth. Using the DOM you can
+traverse the resulting tree any way you like, access element and attribute
+values, insert and delete nodes, and convert the tree back into XML.
+
+The DOM is useful for modifying XML documents, because you can create a DOM
+tree, modify it by adding new nodes or rearranging subtrees, and then produce a
+new XML document as output. You can also construct a DOM tree manually and
+convert it to XML, which can be a more flexible way of producing XML output than
+simply writing ``<tag1>``...\ ``</tag1>`` to a file.
+
+The DOM implementation included with Python lives in the :mod:`xml.dom.minidom`
+module. It's a lightweight implementation of the Level 1 DOM with support for
+XML namespaces. The :func:`parse` and :func:`parseString` convenience
+functions are provided for generating a DOM tree::
+
+ from xml.dom import minidom
+ doc = minidom.parse('hamlet.xml')
+
+``doc`` is a :class:`Document` instance. :class:`Document`, like all the other
+DOM classes such as :class:`Element` and :class:`Text`, is a subclass of the
+:class:`Node` base class. All the nodes in a DOM tree therefore support certain
+common methods, such as :meth:`toxml` which returns a string containing the XML
+representation of the node and its children. Each class also has special
+methods of its own; for example, :class:`Element` and :class:`Document`
+instances have a method to find all child elements with a given tag name.
+Continuing from the previous 2-line example::
+
+ perslist = doc.getElementsByTagName( 'PERSONA' )
+ print perslist[0].toxml()
+ print perslist[1].toxml()
+
+For the *Hamlet* XML file, the above few lines output::
+
+ <PERSONA>CLAUDIUS, king of Denmark. </PERSONA>
+ <PERSONA>HAMLET, son to the late, and nephew to the present king.</PERSONA>
+
+The root element of the document is available as ``doc.documentElement``, and
+its children can be easily modified by deleting, adding, or removing nodes::
+
+ root = doc.documentElement
+
+ # Remove the first child
+ root.removeChild( root.childNodes[0] )
+
+ # Move the new first child to the end
+ root.appendChild( root.childNodes[0] )
+
+ # Insert the new first child (originally,
+ # the third child) before the 20th child.
+ root.insertBefore( root.childNodes[0], root.childNodes[20] )
+
+Again, I will refer you to the Python documentation for a complete listing of
+the different :class:`Node` classes and their various methods.
+
+
+Relationship to PyXML
+---------------------
+
+The XML Special Interest Group has been working on XML-related Python code for a
+while. Its code distribution, called PyXML, is available from the SIG's Web
+pages at http://www.python.org/sigs/xml-sig/. The PyXML distribution also used
+the package name ``xml``. If you've written programs that used PyXML, you're
+probably wondering about its compatibility with the 2.0 :mod:`xml` package.
+
+The answer is that Python 2.0's :mod:`xml` package isn't compatible with PyXML,
+but can be made compatible by installing a recent version PyXML. Many
+applications can get by with the XML support that is included with Python 2.0,
+but more complicated applications will require that the full PyXML package will
+be installed. When installed, PyXML versions 0.6.0 or greater will replace the
+:mod:`xml` package shipped with Python, and will be a strict superset of the
+standard package, adding a bunch of additional features. Some of the additional
+features in PyXML include:
+
+* 4DOM, a full DOM implementation from FourThought, Inc.
+
+* The xmlproc validating parser, written by Lars Marius Garshol.
+
+* The :mod:`sgmlop` parser accelerator module, written by Fredrik Lundh.
+
+.. % ======================================================================
+
+
+Module changes
+==============
+
+Lots of improvements and bugfixes were made to Python's extensive standard
+library; some of the affected modules include :mod:`readline`,
+:mod:`ConfigParser`, :mod:`cgi`, :mod:`calendar`, :mod:`posix`, :mod:`readline`,
+:mod:`xmllib`, :mod:`aifc`, :mod:`chunk, wave`, :mod:`random`, :mod:`shelve`,
+and :mod:`nntplib`. Consult the CVS logs for the exact patch-by-patch details.
+
+Brian Gallew contributed OpenSSL support for the :mod:`socket` module. OpenSSL
+is an implementation of the Secure Socket Layer, which encrypts the data being
+sent over a socket. When compiling Python, you can edit :file:`Modules/Setup`
+to include SSL support, which adds an additional function to the :mod:`socket`
+module: :func:`socket.ssl(socket, keyfile, certfile)`, which takes a socket
+object and returns an SSL socket. The :mod:`httplib` and :mod:`urllib` modules
+were also changed to support "https://" URLs, though no one has implemented FTP
+or SMTP over SSL.
+
+The :mod:`httplib` module has been rewritten by Greg Stein to support HTTP/1.1.
+Backward compatibility with the 1.5 version of :mod:`httplib` is provided,
+though using HTTP/1.1 features such as pipelining will require rewriting code to
+use a different set of interfaces.
+
+The :mod:`Tkinter` module now supports Tcl/Tk version 8.1, 8.2, or 8.3, and
+support for the older 7.x versions has been dropped. The Tkinter module now
+supports displaying Unicode strings in Tk widgets. Also, Fredrik Lundh
+contributed an optimization which makes operations like ``create_line`` and
+``create_polygon`` much faster, especially when using lots of coordinates.
+
+The :mod:`curses` module has been greatly extended, starting from Oliver
+Andrich's enhanced version, to provide many additional functions from ncurses
+and SYSV curses, such as colour, alternative character set support, pads, and
+mouse support. This means the module is no longer compatible with operating
+systems that only have BSD curses, but there don't seem to be any currently
+maintained OSes that fall into this category.
+
+As mentioned in the earlier discussion of 2.0's Unicode support, the underlying
+implementation of the regular expressions provided by the :mod:`re` module has
+been changed. SRE, a new regular expression engine written by Fredrik Lundh and
+partially funded by Hewlett Packard, supports matching against both 8-bit
+strings and Unicode strings.
+
+.. % ======================================================================
+
+
+New modules
+===========
+
+A number of new modules were added. We'll simply list them with brief
+descriptions; consult the 2.0 documentation for the details of a particular
+module.
+
+* :mod:`atexit`: For registering functions to be called before the Python
+ interpreter exits. Code that currently sets ``sys.exitfunc`` directly should be
+ changed to use the :mod:`atexit` module instead, importing :mod:`atexit` and
+ calling :func:`atexit.register` with the function to be called on exit.
+ (Contributed by Skip Montanaro.)
+
+* :mod:`codecs`, :mod:`encodings`, :mod:`unicodedata`: Added as part of the new
+ Unicode support.
+
+* :mod:`filecmp`: Supersedes the old :mod:`cmp`, :mod:`cmpcache` and
+ :mod:`dircmp` modules, which have now become deprecated. (Contributed by Gordon
+ MacMillan and Moshe Zadka.)
+
+* :mod:`gettext`: This module provides internationalization (I18N) and
+ localization (L10N) support for Python programs by providing an interface to the
+ GNU gettext message catalog library. (Integrated by Barry Warsaw, from separate
+ contributions by Martin von Löwis, Peter Funk, and James Henstridge.)
+
+* :mod:`linuxaudiodev`: Support for the :file:`/dev/audio` device on Linux, a
+ twin to the existing :mod:`sunaudiodev` module. (Contributed by Peter Bosch,
+ with fixes by Jeremy Hylton.)
+
+* :mod:`mmap`: An interface to memory-mapped files on both Windows and Unix. A
+ file's contents can be mapped directly into memory, at which point it behaves
+ like a mutable string, so its contents can be read and modified. They can even
+ be passed to functions that expect ordinary strings, such as the :mod:`re`
+ module. (Contributed by Sam Rushing, with some extensions by A.M. Kuchling.)
+
+* :mod:`pyexpat`: An interface to the Expat XML parser. (Contributed by Paul
+ Prescod.)
+
+* :mod:`robotparser`: Parse a :file:`robots.txt` file, which is used for writing
+ Web spiders that politely avoid certain areas of a Web site. The parser accepts
+ the contents of a :file:`robots.txt` file, builds a set of rules from it, and
+ can then answer questions about the fetchability of a given URL. (Contributed
+ by Skip Montanaro.)
+
+* :mod:`tabnanny`: A module/script to check Python source code for ambiguous
+ indentation. (Contributed by Tim Peters.)
+
+* :mod:`UserString`: A base class useful for deriving objects that behave like
+ strings.
+
+* :mod:`webbrowser`: A module that provides a platform independent way to launch
+ a web browser on a specific URL. For each platform, various browsers are tried
+ in a specific order. The user can alter which browser is launched by setting the
+ *BROWSER* environment variable. (Originally inspired by Eric S. Raymond's patch
+ to :mod:`urllib` which added similar functionality, but the final module comes
+ from code originally implemented by Fred Drake as
+ :file:`Tools/idle/BrowserControl.py`, and adapted for the standard library by
+ Fred.)
+
+* :mod:`_winreg`: An interface to the Windows registry. :mod:`_winreg` is an
+ adaptation of functions that have been part of PythonWin since 1995, but has now
+ been added to the core distribution, and enhanced to support Unicode.
+ :mod:`_winreg` was written by Bill Tutt and Mark Hammond.
+
+* :mod:`zipfile`: A module for reading and writing ZIP-format archives. These
+ are archives produced by :program:`PKZIP` on DOS/Windows or :program:`zip` on
+ Unix, not to be confused with :program:`gzip`\ -format files (which are
+ supported by the :mod:`gzip` module) (Contributed by James C. Ahlstrom.)
+
+* :mod:`imputil`: A module that provides a simpler way for writing customised
+ import hooks, in comparison to the existing :mod:`ihooks` module. (Implemented
+ by Greg Stein, with much discussion on python-dev along the way.)
+
+.. % ======================================================================
+
+
+IDLE Improvements
+=================
+
+IDLE is the official Python cross-platform IDE, written using Tkinter. Python
+2.0 includes IDLE 0.6, which adds a number of new features and improvements. A
+partial list:
+
+* UI improvements and optimizations, especially in the area of syntax
+ highlighting and auto-indentation.
+
+* The class browser now shows more information, such as the top level functions
+ in a module.
+
+* Tab width is now a user settable option. When opening an existing Python file,
+ IDLE automatically detects the indentation conventions, and adapts.
+
+* There is now support for calling browsers on various platforms, used to open
+ the Python documentation in a browser.
+
+* IDLE now has a command line, which is largely similar to the vanilla Python
+ interpreter.
+
+* Call tips were added in many places.
+
+* IDLE can now be installed as a package.
+
+* In the editor window, there is now a line/column bar at the bottom.
+
+* Three new keystroke commands: Check module (Alt-F5), Import module (F5) and
+ Run script (Ctrl-F5).
+
+.. % ======================================================================
+
+
+Deleted and Deprecated Modules
+==============================
+
+A few modules have been dropped because they're obsolete, or because there are
+now better ways to do the same thing. The :mod:`stdwin` module is gone; it was
+for a platform-independent windowing toolkit that's no longer developed.
+
+A number of modules have been moved to the :file:`lib-old` subdirectory:
+:mod:`cmp`, :mod:`cmpcache`, :mod:`dircmp`, :mod:`dump`, :mod:`find`,
+:mod:`grep`, :mod:`packmail`, :mod:`poly`, :mod:`util`, :mod:`whatsound`,
+:mod:`zmod`. If you have code which relies on a module that's been moved to
+:file:`lib-old`, you can simply add that directory to ``sys.path`` to get them
+back, but you're encouraged to update any code that uses these modules.
+
+
+Acknowledgements
+================
+
+The authors would like to thank the following people for offering suggestions on
+various drafts of this article: David Bolen, Mark Hammond, Gregg Hauser, Jeremy
+Hylton, Fredrik Lundh, Detlef Lannert, Aahz Maruch, Skip Montanaro, Vladimir
+Marangozov, Tobias Polzin, Guido van Rossum, Neil Schemenauer, and Russ Schmidt.
+
diff --git a/Doc/whatsnew/2.1.rst b/Doc/whatsnew/2.1.rst
new file mode 100644
index 0000000000..2be11baad9
--- /dev/null
+++ b/Doc/whatsnew/2.1.rst
@@ -0,0 +1,794 @@
+****************************
+ What's New in Python 2.1
+****************************
+
+:Author: A.M. Kuchling
+
+.. |release| replace:: 1.01
+
+.. % $Id: whatsnew21.tex 51211 2006-08-11 14:57:12Z thomas.wouters $
+
+
+Introduction
+============
+
+This article explains the new features in Python 2.1. While there aren't as
+many changes in 2.1 as there were in Python 2.0, there are still some pleasant
+surprises in store. 2.1 is the first release to be steered through the use of
+Python Enhancement Proposals, or PEPs, so most of the sizable changes have
+accompanying PEPs that provide more complete documentation and a design
+rationale for the change. This article doesn't attempt to document the new
+features completely, but simply provides an overview of the new features for
+Python programmers. Refer to the Python 2.1 documentation, or to the specific
+PEP, for more details about any new feature that particularly interests you.
+
+One recent goal of the Python development team has been to accelerate the pace
+of new releases, with a new release coming every 6 to 9 months. 2.1 is the first
+release to come out at this faster pace, with the first alpha appearing in
+January, 3 months after the final version of 2.0 was released.
+
+The final release of Python 2.1 was made on April 17, 2001.
+
+.. % ======================================================================
+
+
+PEP 227: Nested Scopes
+======================
+
+The largest change in Python 2.1 is to Python's scoping rules. In Python 2.0,
+at any given time there are at most three namespaces used to look up variable
+names: local, module-level, and the built-in namespace. This often surprised
+people because it didn't match their intuitive expectations. For example, a
+nested recursive function definition doesn't work::
+
+ def f():
+ ...
+ def g(value):
+ ...
+ return g(value-1) + 1
+ ...
+
+The function :func:`g` will always raise a :exc:`NameError` exception, because
+the binding of the name ``g`` isn't in either its local namespace or in the
+module-level namespace. This isn't much of a problem in practice (how often do
+you recursively define interior functions like this?), but this also made using
+the :keyword:`lambda` statement clumsier, and this was a problem in practice.
+In code which uses :keyword:`lambda` you can often find local variables being
+copied by passing them as the default values of arguments. ::
+
+ def find(self, name):
+ "Return list of any entries equal to 'name'"
+ L = filter(lambda x, name=name: x == name,
+ self.list_attribute)
+ return L
+
+The readability of Python code written in a strongly functional style suffers
+greatly as a result.
+
+The most significant change to Python 2.1 is that static scoping has been added
+to the language to fix this problem. As a first effect, the ``name=name``
+default argument is now unnecessary in the above example. Put simply, when a
+given variable name is not assigned a value within a function (by an assignment,
+or the :keyword:`def`, :keyword:`class`, or :keyword:`import` statements),
+references to the variable will be looked up in the local namespace of the
+enclosing scope. A more detailed explanation of the rules, and a dissection of
+the implementation, can be found in the PEP.
+
+This change may cause some compatibility problems for code where the same
+variable name is used both at the module level and as a local variable within a
+function that contains further function definitions. This seems rather unlikely
+though, since such code would have been pretty confusing to read in the first
+place.
+
+One side effect of the change is that the ``from module import *`` and
+:keyword:`exec` statements have been made illegal inside a function scope under
+certain conditions. The Python reference manual has said all along that ``from
+module import *`` is only legal at the top level of a module, but the CPython
+interpreter has never enforced this before. As part of the implementation of
+nested scopes, the compiler which turns Python source into bytecodes has to
+generate different code to access variables in a containing scope. ``from
+module import *`` and :keyword:`exec` make it impossible for the compiler to
+figure this out, because they add names to the local namespace that are
+unknowable at compile time. Therefore, if a function contains function
+definitions or :keyword:`lambda` expressions with free variables, the compiler
+will flag this by raising a :exc:`SyntaxError` exception.
+
+To make the preceding explanation a bit clearer, here's an example::
+
+ x = 1
+ def f():
+ # The next line is a syntax error
+ exec 'x=2'
+ def g():
+ return x
+
+Line 4 containing the :keyword:`exec` statement is a syntax error, since
+:keyword:`exec` would define a new local variable named ``x`` whose value should
+be accessed by :func:`g`.
+
+This shouldn't be much of a limitation, since :keyword:`exec` is rarely used in
+most Python code (and when it is used, it's often a sign of a poor design
+anyway).
+
+Compatibility concerns have led to nested scopes being introduced gradually; in
+Python 2.1, they aren't enabled by default, but can be turned on within a module
+by using a future statement as described in PEP 236. (See the following section
+for further discussion of PEP 236.) In Python 2.2, nested scopes will become
+the default and there will be no way to turn them off, but users will have had
+all of 2.1's lifetime to fix any breakage resulting from their introduction.
+
+
+.. seealso::
+
+ :pep:`227` - Statically Nested Scopes
+ Written and implemented by Jeremy Hylton.
+
+.. % ======================================================================
+
+
+PEP 236: __future__ Directives
+==============================
+
+The reaction to nested scopes was widespread concern about the dangers of
+breaking code with the 2.1 release, and it was strong enough to make the
+Pythoneers take a more conservative approach. This approach consists of
+introducing a convention for enabling optional functionality in release N that
+will become compulsory in release N+1.
+
+The syntax uses a ``from...import`` statement using the reserved module name
+:mod:`__future__`. Nested scopes can be enabled by the following statement::
+
+ from __future__ import nested_scopes
+
+While it looks like a normal :keyword:`import` statement, it's not; there are
+strict rules on where such a future statement can be put. They can only be at
+the top of a module, and must precede any Python code or regular
+:keyword:`import` statements. This is because such statements can affect how
+the Python bytecode compiler parses code and generates bytecode, so they must
+precede any statement that will result in bytecodes being produced.
+
+
+.. seealso::
+
+ :pep:`236` - Back to the :mod:`__future__`
+ Written by Tim Peters, and primarily implemented by Jeremy Hylton.
+
+.. % ======================================================================
+
+
+PEP 207: Rich Comparisons
+=========================
+
+In earlier versions, Python's support for implementing comparisons on user-
+defined classes and extension types was quite simple. Classes could implement a
+:meth:`__cmp__` method that was given two instances of a class, and could only
+return 0 if they were equal or +1 or -1 if they weren't; the method couldn't
+raise an exception or return anything other than a Boolean value. Users of
+Numeric Python often found this model too weak and restrictive, because in the
+number-crunching programs that numeric Python is used for, it would be more
+useful to be able to perform elementwise comparisons of two matrices, returning
+a matrix containing the results of a given comparison for each element. If the
+two matrices are of different sizes, then the compare has to be able to raise an
+exception to signal the error.
+
+In Python 2.1, rich comparisons were added in order to support this need.
+Python classes can now individually overload each of the ``<``, ``<=``, ``>``,
+``>=``, ``==``, and ``!=`` operations. The new magic method names are:
+
++-----------+----------------+
+| Operation | Method name |
++===========+================+
+| ``<`` | :meth:`__lt__` |
++-----------+----------------+
+| ``<=`` | :meth:`__le__` |
++-----------+----------------+
+| ``>`` | :meth:`__gt__` |
++-----------+----------------+
+| ``>=`` | :meth:`__ge__` |
++-----------+----------------+
+| ``==`` | :meth:`__eq__` |
++-----------+----------------+
+| ``!=`` | :meth:`__ne__` |
++-----------+----------------+
+
+(The magic methods are named after the corresponding Fortran operators ``.LT.``.
+``.LE.``, &c. Numeric programmers are almost certainly quite familiar with
+these names and will find them easy to remember.)
+
+Each of these magic methods is of the form ``method(self, other)``, where
+``self`` will be the object on the left-hand side of the operator, while
+``other`` will be the object on the right-hand side. For example, the
+expression ``A < B`` will cause ``A.__lt__(B)`` to be called.
+
+Each of these magic methods can return anything at all: a Boolean, a matrix, a
+list, or any other Python object. Alternatively they can raise an exception if
+the comparison is impossible, inconsistent, or otherwise meaningless.
+
+The built-in :func:`cmp(A,B)` function can use the rich comparison machinery,
+and now accepts an optional argument specifying which comparison operation to
+use; this is given as one of the strings ``"<"``, ``"<="``, ``">"``, ``">="``,
+``"=="``, or ``"!="``. If called without the optional third argument,
+:func:`cmp` will only return -1, 0, or +1 as in previous versions of Python;
+otherwise it will call the appropriate method and can return any Python object.
+
+There are also corresponding changes of interest to C programmers; there's a new
+slot ``tp_richcmp`` in type objects and an API for performing a given rich
+comparison. I won't cover the C API here, but will refer you to PEP 207, or to
+2.1's C API documentation, for the full list of related functions.
+
+
+.. seealso::
+
+ :pep:`207` - Rich Comparisions
+ Written by Guido van Rossum, heavily based on earlier work by David Ascher, and
+ implemented by Guido van Rossum.
+
+.. % ======================================================================
+
+
+PEP 230: Warning Framework
+==========================
+
+Over its 10 years of existence, Python has accumulated a certain number of
+obsolete modules and features along the way. It's difficult to know when a
+feature is safe to remove, since there's no way of knowing how much code uses it
+--- perhaps no programs depend on the feature, or perhaps many do. To enable
+removing old features in a more structured way, a warning framework was added.
+When the Python developers want to get rid of a feature, it will first trigger a
+warning in the next version of Python. The following Python version can then
+drop the feature, and users will have had a full release cycle to remove uses of
+the old feature.
+
+Python 2.1 adds the warning framework to be used in this scheme. It adds a
+:mod:`warnings` module that provide functions to issue warnings, and to filter
+out warnings that you don't want to be displayed. Third-party modules can also
+use this framework to deprecate old features that they no longer wish to
+support.
+
+For example, in Python 2.1 the :mod:`regex` module is deprecated, so importing
+it causes a warning to be printed::
+
+ >>> import regex
+ __main__:1: DeprecationWarning: the regex module
+ is deprecated; please use the re module
+ >>>
+
+Warnings can be issued by calling the :func:`warnings.warn` function::
+
+ warnings.warn("feature X no longer supported")
+
+The first parameter is the warning message; an additional optional parameters
+can be used to specify a particular warning category.
+
+Filters can be added to disable certain warnings; a regular expression pattern
+can be applied to the message or to the module name in order to suppress a
+warning. For example, you may have a program that uses the :mod:`regex` module
+and not want to spare the time to convert it to use the :mod:`re` module right
+now. The warning can be suppressed by calling ::
+
+ import warnings
+ warnings.filterwarnings(action = 'ignore',
+ message='.*regex module is deprecated',
+ category=DeprecationWarning,
+ module = '__main__')
+
+This adds a filter that will apply only to warnings of the class
+:class:`DeprecationWarning` triggered in the :mod:`__main__` module, and applies
+a regular expression to only match the message about the :mod:`regex` module
+being deprecated, and will cause such warnings to be ignored. Warnings can also
+be printed only once, printed every time the offending code is executed, or
+turned into exceptions that will cause the program to stop (unless the
+exceptions are caught in the usual way, of course).
+
+Functions were also added to Python's C API for issuing warnings; refer to PEP
+230 or to Python's API documentation for the details.
+
+
+.. seealso::
+
+ :pep:`5` - Guidelines for Language Evolution
+ Written by Paul Prescod, to specify procedures to be followed when removing old
+ features from Python. The policy described in this PEP hasn't been officially
+ adopted, but the eventual policy probably won't be too different from Prescod's
+ proposal.
+
+ :pep:`230` - Warning Framework
+ Written and implemented by Guido van Rossum.
+
+.. % ======================================================================
+
+
+PEP 229: New Build System
+=========================
+
+When compiling Python, the user had to go in and edit the :file:`Modules/Setup`
+file in order to enable various additional modules; the default set is
+relatively small and limited to modules that compile on most Unix platforms.
+This means that on Unix platforms with many more features, most notably Linux,
+Python installations often don't contain all useful modules they could.
+
+Python 2.0 added the Distutils, a set of modules for distributing and installing
+extensions. In Python 2.1, the Distutils are used to compile much of the
+standard library of extension modules, autodetecting which ones are supported on
+the current machine. It's hoped that this will make Python installations easier
+and more featureful.
+
+Instead of having to edit the :file:`Modules/Setup` file in order to enable
+modules, a :file:`setup.py` script in the top directory of the Python source
+distribution is run at build time, and attempts to discover which modules can be
+enabled by examining the modules and header files on the system. If a module is
+configured in :file:`Modules/Setup`, the :file:`setup.py` script won't attempt
+to compile that module and will defer to the :file:`Modules/Setup` file's
+contents. This provides a way to specific any strange command-line flags or
+libraries that are required for a specific platform.
+
+In another far-reaching change to the build mechanism, Neil Schemenauer
+restructured things so Python now uses a single makefile that isn't recursive,
+instead of makefiles in the top directory and in each of the :file:`Python/`,
+:file:`Parser/`, :file:`Objects/`, and :file:`Modules/` subdirectories. This
+makes building Python faster and also makes hacking the Makefiles clearer and
+simpler.
+
+
+.. seealso::
+
+ :pep:`229` - Using Distutils to Build Python
+ Written and implemented by A.M. Kuchling.
+
+.. % ======================================================================
+
+
+PEP 205: Weak References
+========================
+
+Weak references, available through the :mod:`weakref` module, are a minor but
+useful new data type in the Python programmer's toolbox.
+
+Storing a reference to an object (say, in a dictionary or a list) has the side
+effect of keeping that object alive forever. There are a few specific cases
+where this behaviour is undesirable, object caches being the most common one,
+and another being circular references in data structures such as trees.
+
+For example, consider a memoizing function that caches the results of another
+function :func:`f(x)` by storing the function's argument and its result in a
+dictionary::
+
+ _cache = {}
+ def memoize(x):
+ if _cache.has_key(x):
+ return _cache[x]
+
+ retval = f(x)
+
+ # Cache the returned object
+ _cache[x] = retval
+
+ return retval
+
+This version works for simple things such as integers, but it has a side effect;
+the ``_cache`` dictionary holds a reference to the return values, so they'll
+never be deallocated until the Python process exits and cleans up This isn't
+very noticeable for integers, but if :func:`f` returns an object, or a data
+structure that takes up a lot of memory, this can be a problem.
+
+Weak references provide a way to implement a cache that won't keep objects alive
+beyond their time. If an object is only accessible through weak references, the
+object will be deallocated and the weak references will now indicate that the
+object it referred to no longer exists. A weak reference to an object *obj* is
+created by calling ``wr = weakref.ref(obj)``. The object being referred to is
+returned by calling the weak reference as if it were a function: ``wr()``. It
+will return the referenced object, or ``None`` if the object no longer exists.
+
+This makes it possible to write a :func:`memoize` function whose cache doesn't
+keep objects alive, by storing weak references in the cache. ::
+
+ _cache = {}
+ def memoize(x):
+ if _cache.has_key(x):
+ obj = _cache[x]()
+ # If weak reference object still exists,
+ # return it
+ if obj is not None: return obj
+
+ retval = f(x)
+
+ # Cache a weak reference
+ _cache[x] = weakref.ref(retval)
+
+ return retval
+
+The :mod:`weakref` module also allows creating proxy objects which behave like
+weak references --- an object referenced only by proxy objects is deallocated --
+but instead of requiring an explicit call to retrieve the object, the proxy
+transparently forwards all operations to the object as long as the object still
+exists. If the object is deallocated, attempting to use a proxy will cause a
+:exc:`weakref.ReferenceError` exception to be raised. ::
+
+ proxy = weakref.proxy(obj)
+ proxy.attr # Equivalent to obj.attr
+ proxy.meth() # Equivalent to obj.meth()
+ del obj
+ proxy.attr # raises weakref.ReferenceError
+
+
+.. seealso::
+
+ :pep:`205` - Weak References
+ Written and implemented by Fred L. Drake, Jr.
+
+.. % ======================================================================
+
+
+PEP 232: Function Attributes
+============================
+
+In Python 2.1, functions can now have arbitrary information attached to them.
+People were often using docstrings to hold information about functions and
+methods, because the ``__doc__`` attribute was the only way of attaching any
+information to a function. For example, in the Zope Web application server,
+functions are marked as safe for public access by having a docstring, and in
+John Aycock's SPARK parsing framework, docstrings hold parts of the BNF grammar
+to be parsed. This overloading is unfortunate, since docstrings are really
+intended to hold a function's documentation; for example, it means you can't
+properly document functions intended for private use in Zope.
+
+Arbitrary attributes can now be set and retrieved on functions using the regular
+Python syntax::
+
+ def f(): pass
+
+ f.publish = 1
+ f.secure = 1
+ f.grammar = "A ::= B (C D)*"
+
+The dictionary containing attributes can be accessed as the function's
+:attr:`__dict__`. Unlike the :attr:`__dict__` attribute of class instances, in
+functions you can actually assign a new dictionary to :attr:`__dict__`, though
+the new value is restricted to a regular Python dictionary; you *can't* be
+tricky and set it to a :class:`UserDict` instance, or any other random object
+that behaves like a mapping.
+
+
+.. seealso::
+
+ :pep:`232` - Function Attributes
+ Written and implemented by Barry Warsaw.
+
+.. % ======================================================================
+
+
+PEP 235: Importing Modules on Case-Insensitive Platforms
+========================================================
+
+Some operating systems have filesystems that are case-insensitive, MacOS and
+Windows being the primary examples; on these systems, it's impossible to
+distinguish the filenames ``FILE.PY`` and ``file.py``, even though they do store
+the file's name in its original case (they're case-preserving, too).
+
+In Python 2.1, the :keyword:`import` statement will work to simulate case-
+sensitivity on case-insensitive platforms. Python will now search for the first
+case-sensitive match by default, raising an :exc:`ImportError` if no such file
+is found, so ``import file`` will not import a module named ``FILE.PY``. Case-
+insensitive matching can be requested by setting the :envvar:`PYTHONCASEOK`
+environment variable before starting the Python interpreter.
+
+.. % ======================================================================
+
+
+PEP 217: Interactive Display Hook
+=================================
+
+When using the Python interpreter interactively, the output of commands is
+displayed using the built-in :func:`repr` function. In Python 2.1, the variable
+:func:`sys.displayhook` can be set to a callable object which will be called
+instead of :func:`repr`. For example, you can set it to a special pretty-
+printing function::
+
+ >>> # Create a recursive data structure
+ ... L = [1,2,3]
+ >>> L.append(L)
+ >>> L # Show Python's default output
+ [1, 2, 3, [...]]
+ >>> # Use pprint.pprint() as the display function
+ ... import sys, pprint
+ >>> sys.displayhook = pprint.pprint
+ >>> L
+ [1, 2, 3, <Recursion on list with id=135143996>]
+ >>>
+
+
+.. seealso::
+
+ :pep:`217` - Display Hook for Interactive Use
+ Written and implemented by Moshe Zadka.
+
+.. % ======================================================================
+
+
+PEP 208: New Coercion Model
+===========================
+
+How numeric coercion is done at the C level was significantly modified. This
+will only affect the authors of C extensions to Python, allowing them more
+flexibility in writing extension types that support numeric operations.
+
+Extension types can now set the type flag ``Py_TPFLAGS_CHECKTYPES`` in their
+``PyTypeObject`` structure to indicate that they support the new coercion model.
+In such extension types, the numeric slot functions can no longer assume that
+they'll be passed two arguments of the same type; instead they may be passed two
+arguments of differing types, and can then perform their own internal coercion.
+If the slot function is passed a type it can't handle, it can indicate the
+failure by returning a reference to the ``Py_NotImplemented`` singleton value.
+The numeric functions of the other type will then be tried, and perhaps they can
+handle the operation; if the other type also returns ``Py_NotImplemented``, then
+a :exc:`TypeError` will be raised. Numeric methods written in Python can also
+return ``Py_NotImplemented``, causing the interpreter to act as if the method
+did not exist (perhaps raising a :exc:`TypeError`, perhaps trying another
+object's numeric methods).
+
+
+.. seealso::
+
+ :pep:`208` - Reworking the Coercion Model
+ Written and implemented by Neil Schemenauer, heavily based upon earlier work by
+ Marc-André Lemburg. Read this to understand the fine points of how numeric
+ operations will now be processed at the C level.
+
+.. % ======================================================================
+
+
+PEP 241: Metadata in Python Packages
+====================================
+
+A common complaint from Python users is that there's no single catalog of all
+the Python modules in existence. T. Middleton's Vaults of Parnassus at
+http://www.vex.net/parnassus/ are the largest catalog of Python modules, but
+registering software at the Vaults is optional, and many people don't bother.
+
+As a first small step toward fixing the problem, Python software packaged using
+the Distutils :command:`sdist` command will include a file named
+:file:`PKG-INFO` containing information about the package such as its name,
+version, and author (metadata, in cataloguing terminology). PEP 241 contains
+the full list of fields that can be present in the :file:`PKG-INFO` file. As
+people began to package their software using Python 2.1, more and more packages
+will include metadata, making it possible to build automated cataloguing systems
+and experiment with them. With the result experience, perhaps it'll be possible
+to design a really good catalog and then build support for it into Python 2.2.
+For example, the Distutils :command:`sdist` and :command:`bdist_\*` commands
+could support a :option:`upload` option that would automatically upload your
+package to a catalog server.
+
+You can start creating packages containing :file:`PKG-INFO` even if you're not
+using Python 2.1, since a new release of the Distutils will be made for users of
+earlier Python versions. Version 1.0.2 of the Distutils includes the changes
+described in PEP 241, as well as various bugfixes and enhancements. It will be
+available from the Distutils SIG at http://www.python.org/sigs/distutils-sig/.
+
+
+.. seealso::
+
+ :pep:`241` - Metadata for Python Software Packages
+ Written and implemented by A.M. Kuchling.
+
+ :pep:`243` - Module Repository Upload Mechanism
+ Written by Sean Reifschneider, this draft PEP describes a proposed mechanism for
+ uploading Python packages to a central server.
+
+.. % ======================================================================
+
+
+New and Improved Modules
+========================
+
+* Ka-Ping Yee contributed two new modules: :mod:`inspect.py`, a module for
+ getting information about live Python code, and :mod:`pydoc.py`, a module for
+ interactively converting docstrings to HTML or text. As a bonus,
+ :file:`Tools/scripts/pydoc`, which is now automatically installed, uses
+ :mod:`pydoc.py` to display documentation given a Python module, package, or
+ class name. For example, ``pydoc xml.dom`` displays the following::
+
+ Python Library Documentation: package xml.dom in xml
+
+ NAME
+ xml.dom - W3C Document Object Model implementation for Python.
+
+ FILE
+ /usr/local/lib/python2.1/xml/dom/__init__.pyc
+
+ DESCRIPTION
+ The Python mapping of the Document Object Model is documented in the
+ Python Library Reference in the section on the xml.dom package.
+
+ This package contains the following modules:
+ ...
+
+ :file:`pydoc` also includes a Tk-based interactive help browser. :file:`pydoc`
+ quickly becomes addictive; try it out!
+
+* Two different modules for unit testing were added to the standard library.
+ The :mod:`doctest` module, contributed by Tim Peters, provides a testing
+ framework based on running embedded examples in docstrings and comparing the
+ results against the expected output. PyUnit, contributed by Steve Purcell, is a
+ unit testing framework inspired by JUnit, which was in turn an adaptation of
+ Kent Beck's Smalltalk testing framework. See http://pyunit.sourceforge.net/ for
+ more information about PyUnit.
+
+* The :mod:`difflib` module contains a class, :class:`SequenceMatcher`, which
+ compares two sequences and computes the changes required to transform one
+ sequence into the other. For example, this module can be used to write a tool
+ similar to the Unix :program:`diff` program, and in fact the sample program
+ :file:`Tools/scripts/ndiff.py` demonstrates how to write such a script.
+
+* :mod:`curses.panel`, a wrapper for the panel library, part of ncurses and of
+ SYSV curses, was contributed by Thomas Gellekum. The panel library provides
+ windows with the additional feature of depth. Windows can be moved higher or
+ lower in the depth ordering, and the panel library figures out where panels
+ overlap and which sections are visible.
+
+* The PyXML package has gone through a few releases since Python 2.0, and Python
+ 2.1 includes an updated version of the :mod:`xml` package. Some of the
+ noteworthy changes include support for Expat 1.2 and later versions, the ability
+ for Expat parsers to handle files in any encoding supported by Python, and
+ various bugfixes for SAX, DOM, and the :mod:`minidom` module.
+
+* Ping also contributed another hook for handling uncaught exceptions.
+ :func:`sys.excepthook` can be set to a callable object. When an exception isn't
+ caught by any :keyword:`try`...\ :keyword:`except` blocks, the exception will be
+ passed to :func:`sys.excepthook`, which can then do whatever it likes. At the
+ Ninth Python Conference, Ping demonstrated an application for this hook:
+ printing an extended traceback that not only lists the stack frames, but also
+ lists the function arguments and the local variables for each frame.
+
+* Various functions in the :mod:`time` module, such as :func:`asctime` and
+ :func:`localtime`, require a floating point argument containing the time in
+ seconds since the epoch. The most common use of these functions is to work with
+ the current time, so the floating point argument has been made optional; when a
+ value isn't provided, the current time will be used. For example, log file
+ entries usually need a string containing the current time; in Python 2.1,
+ ``time.asctime()`` can be used, instead of the lengthier
+ ``time.asctime(time.localtime(time.time()))`` that was previously required.
+
+ This change was proposed and implemented by Thomas Wouters.
+
+* The :mod:`ftplib` module now defaults to retrieving files in passive mode,
+ because passive mode is more likely to work from behind a firewall. This
+ request came from the Debian bug tracking system, since other Debian packages
+ use :mod:`ftplib` to retrieve files and then don't work from behind a firewall.
+ It's deemed unlikely that this will cause problems for anyone, because Netscape
+ defaults to passive mode and few people complain, but if passive mode is
+ unsuitable for your application or network setup, call :meth:`set_pasv(0)` on
+ FTP objects to disable passive mode.
+
+* Support for raw socket access has been added to the :mod:`socket` module,
+ contributed by Grant Edwards.
+
+* The :mod:`pstats` module now contains a simple interactive statistics browser
+ for displaying timing profiles for Python programs, invoked when the module is
+ run as a script. Contributed by Eric S. Raymond.
+
+* A new implementation-dependent function, :func:`sys._getframe([depth])`, has
+ been added to return a given frame object from the current call stack.
+ :func:`sys._getframe` returns the frame at the top of the call stack; if the
+ optional integer argument *depth* is supplied, the function returns the frame
+ that is *depth* calls below the top of the stack. For example,
+ ``sys._getframe(1)`` returns the caller's frame object.
+
+ This function is only present in CPython, not in Jython or the .NET
+ implementation. Use it for debugging, and resist the temptation to put it into
+ production code.
+
+.. % ======================================================================
+
+
+Other Changes and Fixes
+=======================
+
+There were relatively few smaller changes made in Python 2.1 due to the shorter
+release cycle. A search through the CVS change logs turns up 117 patches
+applied, and 136 bugs fixed; both figures are likely to be underestimates. Some
+of the more notable changes are:
+
+* A specialized object allocator is now optionally available, that should be
+ faster than the system :func:`malloc` and have less memory overhead. The
+ allocator uses C's :func:`malloc` function to get large pools of memory, and
+ then fulfills smaller memory requests from these pools. It can be enabled by
+ providing the :option:`--with-pymalloc` option to the :program:`configure`
+ script; see :file:`Objects/obmalloc.c` for the implementation details.
+
+ Authors of C extension modules should test their code with the object allocator
+ enabled, because some incorrect code may break, causing core dumps at runtime.
+ There are a bunch of memory allocation functions in Python's C API that have
+ previously been just aliases for the C library's :func:`malloc` and
+ :func:`free`, meaning that if you accidentally called mismatched functions, the
+ error wouldn't be noticeable. When the object allocator is enabled, these
+ functions aren't aliases of :func:`malloc` and :func:`free` any more, and
+ calling the wrong function to free memory will get you a core dump. For
+ example, if memory was allocated using :func:`PyMem_New`, it has to be freed
+ using :func:`PyMem_Del`, not :func:`free`. A few modules included with Python
+ fell afoul of this and had to be fixed; doubtless there are more third-party
+ modules that will have the same problem.
+
+ The object allocator was contributed by Vladimir Marangozov.
+
+* The speed of line-oriented file I/O has been improved because people often
+ complain about its lack of speed, and because it's often been used as a naïve
+ benchmark. The :meth:`readline` method of file objects has therefore been
+ rewritten to be much faster. The exact amount of the speedup will vary from
+ platform to platform depending on how slow the C library's :func:`getc` was, but
+ is around 66%, and potentially much faster on some particular operating systems.
+ Tim Peters did much of the benchmarking and coding for this change, motivated by
+ a discussion in comp.lang.python.
+
+ A new module and method for file objects was also added, contributed by Jeff
+ Epler. The new method, :meth:`xreadlines`, is similar to the existing
+ :func:`xrange` built-in. :func:`xreadlines` returns an opaque sequence object
+ that only supports being iterated over, reading a line on every iteration but
+ not reading the entire file into memory as the existing :meth:`readlines` method
+ does. You'd use it like this::
+
+ for line in sys.stdin.xreadlines():
+ # ... do something for each line ...
+ ...
+
+ For a fuller discussion of the line I/O changes, see the python-dev summary for
+ January 1-15, 2001 at http://www.python.org/dev/summary/2001-01-1.html.
+
+* A new method, :meth:`popitem`, was added to dictionaries to enable
+ destructively iterating through the contents of a dictionary; this can be faster
+ for large dictionaries because there's no need to construct a list containing
+ all the keys or values. ``D.popitem()`` removes a random ``(key, value)`` pair
+ from the dictionary ``D`` and returns it as a 2-tuple. This was implemented
+ mostly by Tim Peters and Guido van Rossum, after a suggestion and preliminary
+ patch by Moshe Zadka.
+
+* Modules can now control which names are imported when ``from module import *``
+ is used, by defining an ``__all__`` attribute containing a list of names that
+ will be imported. One common complaint is that if the module imports other
+ modules such as :mod:`sys` or :mod:`string`, ``from module import *`` will add
+ them to the importing module's namespace. To fix this, simply list the public
+ names in ``__all__``::
+
+ # List public names
+ __all__ = ['Database', 'open']
+
+ A stricter version of this patch was first suggested and implemented by Ben
+ Wolfson, but after some python-dev discussion, a weaker final version was
+ checked in.
+
+* Applying :func:`repr` to strings previously used octal escapes for
+ non-printable characters; for example, a newline was ``'\012'``. This was a
+ vestigial trace of Python's C ancestry, but today octal is of very little
+ practical use. Ka-Ping Yee suggested using hex escapes instead of octal ones,
+ and using the ``\n``, ``\t``, ``\r`` escapes for the appropriate characters,
+ and implemented this new formatting.
+
+* Syntax errors detected at compile-time can now raise exceptions containing the
+ filename and line number of the error, a pleasant side effect of the compiler
+ reorganization done by Jeremy Hylton.
+
+* C extensions which import other modules have been changed to use
+ :func:`PyImport_ImportModule`, which means that they will use any import hooks
+ that have been installed. This is also encouraged for third-party extensions
+ that need to import some other module from C code.
+
+* The size of the Unicode character database was shrunk by another 340K thanks
+ to Fredrik Lundh.
+
+* Some new ports were contributed: MacOS X (by Steven Majewski), Cygwin (by
+ Jason Tishler); RISCOS (by Dietmar Schwertberger); Unixware 7 (by Billy G.
+ Allie).
+
+And there's the usual list of minor bugfixes, minor memory leaks, docstring
+edits, and other tweaks, too lengthy to be worth itemizing; see the CVS logs for
+the full details if you want them.
+
+.. % ======================================================================
+
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions on
+various drafts of this article: Graeme Cross, David Goodger, Jay Graves, Michael
+Hudson, Marc-André Lemburg, Fredrik Lundh, Neil Schemenauer, Thomas Wouters.
+
diff --git a/Doc/whatsnew/2.2.rst b/Doc/whatsnew/2.2.rst
new file mode 100644
index 0000000000..6a7e0e8b07
--- /dev/null
+++ b/Doc/whatsnew/2.2.rst
@@ -0,0 +1,1269 @@
+****************************
+ What's New in Python 2.2
+****************************
+
+:Author: A.M. Kuchling
+
+.. |release| replace:: 1.02
+
+.. % $Id: whatsnew22.tex 37315 2004-09-10 19:33:00Z akuchling $
+
+
+Introduction
+============
+
+This article explains the new features in Python 2.2.2, released on October 14,
+2002. Python 2.2.2 is a bugfix release of Python 2.2, originally released on
+December 21, 2001.
+
+Python 2.2 can be thought of as the "cleanup release". There are some features
+such as generators and iterators that are completely new, but most of the
+changes, significant and far-reaching though they may be, are aimed at cleaning
+up irregularities and dark corners of the language design.
+
+This article doesn't attempt to provide a complete specification of the new
+features, but instead provides a convenient overview. For full details, you
+should refer to the documentation for Python 2.2, such as the `Python Library
+Reference <http://www.python.org/doc/2.2/lib/lib.html>`_ and the `Python
+Reference Manual <http://www.python.org/doc/2.2/ref/ref.html>`_. If you want to
+understand the complete implementation and design rationale for a change, refer
+to the PEP for a particular new feature.
+
+
+.. seealso::
+
+ http://www.unixreview.com/documents/s=1356/urm0109h/0109h.htm
+ "What's So Special About Python 2.2?" is also about the new 2.2 features, and
+ was written by Cameron Laird and Kathryn Soraiz.
+
+.. % ======================================================================
+
+
+PEPs 252 and 253: Type and Class Changes
+========================================
+
+The largest and most far-reaching changes in Python 2.2 are to Python's model of
+objects and classes. The changes should be backward compatible, so it's likely
+that your code will continue to run unchanged, but the changes provide some
+amazing new capabilities. Before beginning this, the longest and most
+complicated section of this article, I'll provide an overview of the changes and
+offer some comments.
+
+A long time ago I wrote a Web page (http://www.amk.ca/python/writing/warts.html)
+listing flaws in Python's design. One of the most significant flaws was that
+it's impossible to subclass Python types implemented in C. In particular, it's
+not possible to subclass built-in types, so you can't just subclass, say, lists
+in order to add a single useful method to them. The :mod:`UserList` module
+provides a class that supports all of the methods of lists and that can be
+subclassed further, but there's lots of C code that expects a regular Python
+list and won't accept a :class:`UserList` instance.
+
+Python 2.2 fixes this, and in the process adds some exciting new capabilities.
+A brief summary:
+
+* You can subclass built-in types such as lists and even integers, and your
+ subclasses should work in every place that requires the original type.
+
+* It's now possible to define static and class methods, in addition to the
+ instance methods available in previous versions of Python.
+
+* It's also possible to automatically call methods on accessing or setting an
+ instance attribute by using a new mechanism called :dfn:`properties`. Many uses
+ of :meth:`__getattr__` can be rewritten to use properties instead, making the
+ resulting code simpler and faster. As a small side benefit, attributes can now
+ have docstrings, too.
+
+* The list of legal attributes for an instance can be limited to a particular
+ set using :dfn:`slots`, making it possible to safeguard against typos and
+ perhaps make more optimizations possible in future versions of Python.
+
+Some users have voiced concern about all these changes. Sure, they say, the new
+features are neat and lend themselves to all sorts of tricks that weren't
+possible in previous versions of Python, but they also make the language more
+complicated. Some people have said that they've always recommended Python for
+its simplicity, and feel that its simplicity is being lost.
+
+Personally, I think there's no need to worry. Many of the new features are
+quite esoteric, and you can write a lot of Python code without ever needed to be
+aware of them. Writing a simple class is no more difficult than it ever was, so
+you don't need to bother learning or teaching them unless they're actually
+needed. Some very complicated tasks that were previously only possible from C
+will now be possible in pure Python, and to my mind that's all for the better.
+
+I'm not going to attempt to cover every single corner case and small change that
+were required to make the new features work. Instead this section will paint
+only the broad strokes. See section :ref:`sect-rellinks`, "Related Links", for
+further sources of information about Python 2.2's new object model.
+
+
+Old and New Classes
+-------------------
+
+First, you should know that Python 2.2 really has two kinds of classes: classic
+or old-style classes, and new-style classes. The old-style class model is
+exactly the same as the class model in earlier versions of Python. All the new
+features described in this section apply only to new-style classes. This
+divergence isn't intended to last forever; eventually old-style classes will be
+dropped, possibly in Python 3.0.
+
+So how do you define a new-style class? You do it by subclassing an existing
+new-style class. Most of Python's built-in types, such as integers, lists,
+dictionaries, and even files, are new-style classes now. A new-style class
+named :class:`object`, the base class for all built-in types, has also been
+added so if no built-in type is suitable, you can just subclass
+:class:`object`::
+
+ class C(object):
+ def __init__ (self):
+ ...
+ ...
+
+This means that :keyword:`class` statements that don't have any base classes are
+always classic classes in Python 2.2. (Actually you can also change this by
+setting a module-level variable named :attr:`__metaclass__` --- see :pep:`253`
+for the details --- but it's easier to just subclass :keyword:`object`.)
+
+The type objects for the built-in types are available as built-ins, named using
+a clever trick. Python has always had built-in functions named :func:`int`,
+:func:`float`, and :func:`str`. In 2.2, they aren't functions any more, but
+type objects that behave as factories when called. ::
+
+ >>> int
+ <type 'int'>
+ >>> int('123')
+ 123
+
+To make the set of types complete, new type objects such as :func:`dict` and
+:func:`file` have been added. Here's a more interesting example, adding a
+:meth:`lock` method to file objects::
+
+ class LockableFile(file):
+ def lock (self, operation, length=0, start=0, whence=0):
+ import fcntl
+ return fcntl.lockf(self.fileno(), operation,
+ length, start, whence)
+
+The now-obsolete :mod:`posixfile` module contained a class that emulated all of
+a file object's methods and also added a :meth:`lock` method, but this class
+couldn't be passed to internal functions that expected a built-in file,
+something which is possible with our new :class:`LockableFile`.
+
+
+Descriptors
+-----------
+
+In previous versions of Python, there was no consistent way to discover what
+attributes and methods were supported by an object. There were some informal
+conventions, such as defining :attr:`__members__` and :attr:`__methods__`
+attributes that were lists of names, but often the author of an extension type
+or a class wouldn't bother to define them. You could fall back on inspecting
+the :attr:`__dict__` of an object, but when class inheritance or an arbitrary
+:meth:`__getattr__` hook were in use this could still be inaccurate.
+
+The one big idea underlying the new class model is that an API for describing
+the attributes of an object using :dfn:`descriptors` has been formalized.
+Descriptors specify the value of an attribute, stating whether it's a method or
+a field. With the descriptor API, static methods and class methods become
+possible, as well as more exotic constructs.
+
+Attribute descriptors are objects that live inside class objects, and have a few
+attributes of their own:
+
+* :attr:`__name__` is the attribute's name.
+
+* :attr:`__doc__` is the attribute's docstring.
+
+* :meth:`__get__(object)` is a method that retrieves the attribute value from
+ *object*.
+
+* :meth:`__set__(object, value)` sets the attribute on *object* to *value*.
+
+* :meth:`__delete__(object, value)` deletes the *value* attribute of *object*.
+
+For example, when you write ``obj.x``, the steps that Python actually performs
+are::
+
+ descriptor = obj.__class__.x
+ descriptor.__get__(obj)
+
+For methods, :meth:`descriptor.__get__` returns a temporary object that's
+callable, and wraps up the instance and the method to be called on it. This is
+also why static methods and class methods are now possible; they have
+descriptors that wrap up just the method, or the method and the class. As a
+brief explanation of these new kinds of methods, static methods aren't passed
+the instance, and therefore resemble regular functions. Class methods are
+passed the class of the object, but not the object itself. Static and class
+methods are defined like this::
+
+ class C(object):
+ def f(arg1, arg2):
+ ...
+ f = staticmethod(f)
+
+ def g(cls, arg1, arg2):
+ ...
+ g = classmethod(g)
+
+The :func:`staticmethod` function takes the function :func:`f`, and returns it
+wrapped up in a descriptor so it can be stored in the class object. You might
+expect there to be special syntax for creating such methods (``def static f``,
+``defstatic f()``, or something like that) but no such syntax has been defined
+yet; that's been left for future versions of Python.
+
+More new features, such as slots and properties, are also implemented as new
+kinds of descriptors, and it's not difficult to write a descriptor class that
+does something novel. For example, it would be possible to write a descriptor
+class that made it possible to write Eiffel-style preconditions and
+postconditions for a method. A class that used this feature might be defined
+like this::
+
+ from eiffel import eiffelmethod
+
+ class C(object):
+ def f(self, arg1, arg2):
+ # The actual function
+ ...
+ def pre_f(self):
+ # Check preconditions
+ ...
+ def post_f(self):
+ # Check postconditions
+ ...
+
+ f = eiffelmethod(f, pre_f, post_f)
+
+Note that a person using the new :func:`eiffelmethod` doesn't have to understand
+anything about descriptors. This is why I think the new features don't increase
+the basic complexity of the language. There will be a few wizards who need to
+know about it in order to write :func:`eiffelmethod` or the ZODB or whatever,
+but most users will just write code on top of the resulting libraries and ignore
+the implementation details.
+
+
+Multiple Inheritance: The Diamond Rule
+--------------------------------------
+
+Multiple inheritance has also been made more useful through changing the rules
+under which names are resolved. Consider this set of classes (diagram taken
+from :pep:`253` by Guido van Rossum)::
+
+ class A:
+ ^ ^ def save(self): ...
+ / \
+ / \
+ / \
+ / \
+ class B class C:
+ ^ ^ def save(self): ...
+ \ /
+ \ /
+ \ /
+ \ /
+ class D
+
+The lookup rule for classic classes is simple but not very smart; the base
+classes are searched depth-first, going from left to right. A reference to
+:meth:`D.save` will search the classes :class:`D`, :class:`B`, and then
+:class:`A`, where :meth:`save` would be found and returned. :meth:`C.save`
+would never be found at all. This is bad, because if :class:`C`'s :meth:`save`
+method is saving some internal state specific to :class:`C`, not calling it will
+result in that state never getting saved.
+
+New-style classes follow a different algorithm that's a bit more complicated to
+explain, but does the right thing in this situation. (Note that Python 2.3
+changes this algorithm to one that produces the same results in most cases, but
+produces more useful results for really complicated inheritance graphs.)
+
+#. List all the base classes, following the classic lookup rule and include a
+ class multiple times if it's visited repeatedly. In the above example, the list
+ of visited classes is [:class:`D`, :class:`B`, :class:`A`, :class:`C`,
+ :class:`A`].
+
+#. Scan the list for duplicated classes. If any are found, remove all but one
+ occurrence, leaving the *last* one in the list. In the above example, the list
+ becomes [:class:`D`, :class:`B`, :class:`C`, :class:`A`] after dropping
+ duplicates.
+
+Following this rule, referring to :meth:`D.save` will return :meth:`C.save`,
+which is the behaviour we're after. This lookup rule is the same as the one
+followed by Common Lisp. A new built-in function, :func:`super`, provides a way
+to get at a class's superclasses without having to reimplement Python's
+algorithm. The most commonly used form will be :func:`super(class, obj)`, which
+returns a bound superclass object (not the actual class object). This form
+will be used in methods to call a method in the superclass; for example,
+:class:`D`'s :meth:`save` method would look like this::
+
+ class D (B,C):
+ def save (self):
+ # Call superclass .save()
+ super(D, self).save()
+ # Save D's private information here
+ ...
+
+:func:`super` can also return unbound superclass objects when called as
+:func:`super(class)` or :func:`super(class1, class2)`, but this probably won't
+often be useful.
+
+
+Attribute Access
+----------------
+
+A fair number of sophisticated Python classes define hooks for attribute access
+using :meth:`__getattr__`; most commonly this is done for convenience, to make
+code more readable by automatically mapping an attribute access such as
+``obj.parent`` into a method call such as ``obj.get_parent``. Python 2.2 adds
+some new ways of controlling attribute access.
+
+First, :meth:`__getattr__(attr_name)` is still supported by new-style classes,
+and nothing about it has changed. As before, it will be called when an attempt
+is made to access ``obj.foo`` and no attribute named ``foo`` is found in the
+instance's dictionary.
+
+New-style classes also support a new method,
+:meth:`__getattribute__(attr_name)`. The difference between the two methods is
+that :meth:`__getattribute__` is *always* called whenever any attribute is
+accessed, while the old :meth:`__getattr__` is only called if ``foo`` isn't
+found in the instance's dictionary.
+
+However, Python 2.2's support for :dfn:`properties` will often be a simpler way
+to trap attribute references. Writing a :meth:`__getattr__` method is
+complicated because to avoid recursion you can't use regular attribute accesses
+inside them, and instead have to mess around with the contents of
+:attr:`__dict__`. :meth:`__getattr__` methods also end up being called by Python
+when it checks for other methods such as :meth:`__repr__` or :meth:`__coerce__`,
+and so have to be written with this in mind. Finally, calling a function on
+every attribute access results in a sizable performance loss.
+
+:class:`property` is a new built-in type that packages up three functions that
+get, set, or delete an attribute, and a docstring. For example, if you want to
+define a :attr:`size` attribute that's computed, but also settable, you could
+write::
+
+ class C(object):
+ def get_size (self):
+ result = ... computation ...
+ return result
+ def set_size (self, size):
+ ... compute something based on the size
+ and set internal state appropriately ...
+
+ # Define a property. The 'delete this attribute'
+ # method is defined as None, so the attribute
+ # can't be deleted.
+ size = property(get_size, set_size,
+ None,
+ "Storage size of this instance")
+
+That is certainly clearer and easier to write than a pair of
+:meth:`__getattr__`/:meth:`__setattr__` methods that check for the :attr:`size`
+attribute and handle it specially while retrieving all other attributes from the
+instance's :attr:`__dict__`. Accesses to :attr:`size` are also the only ones
+which have to perform the work of calling a function, so references to other
+attributes run at their usual speed.
+
+Finally, it's possible to constrain the list of attributes that can be
+referenced on an object using the new :attr:`__slots__` class attribute. Python
+objects are usually very dynamic; at any time it's possible to define a new
+attribute on an instance by just doing ``obj.new_attr=1``. A new-style class
+can define a class attribute named :attr:`__slots__` to limit the legal
+attributes to a particular set of names. An example will make this clear::
+
+ >>> class C(object):
+ ... __slots__ = ('template', 'name')
+ ...
+ >>> obj = C()
+ >>> print obj.template
+ None
+ >>> obj.template = 'Test'
+ >>> print obj.template
+ Test
+ >>> obj.newattr = None
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ AttributeError: 'C' object has no attribute 'newattr'
+
+Note how you get an :exc:`AttributeError` on the attempt to assign to an
+attribute not listed in :attr:`__slots__`.
+
+
+.. _sect-rellinks:
+
+Related Links
+-------------
+
+This section has just been a quick overview of the new features, giving enough
+of an explanation to start you programming, but many details have been
+simplified or ignored. Where should you go to get a more complete picture?
+
+http://www.python.org/2.2/descrintro.html is a lengthy tutorial introduction to
+the descriptor features, written by Guido van Rossum. If my description has
+whetted your appetite, go read this tutorial next, because it goes into much
+more detail about the new features while still remaining quite easy to read.
+
+Next, there are two relevant PEPs, :pep:`252` and :pep:`253`. :pep:`252` is
+titled "Making Types Look More Like Classes", and covers the descriptor API.
+:pep:`253` is titled "Subtyping Built-in Types", and describes the changes to
+type objects that make it possible to subtype built-in objects. :pep:`253` is
+the more complicated PEP of the two, and at a few points the necessary
+explanations of types and meta-types may cause your head to explode. Both PEPs
+were written and implemented by Guido van Rossum, with substantial assistance
+from the rest of the Zope Corp. team.
+
+Finally, there's the ultimate authority: the source code. Most of the machinery
+for the type handling is in :file:`Objects/typeobject.c`, but you should only
+resort to it after all other avenues have been exhausted, including posting a
+question to python-list or python-dev.
+
+.. % ======================================================================
+
+
+PEP 234: Iterators
+==================
+
+Another significant addition to 2.2 is an iteration interface at both the C and
+Python levels. Objects can define how they can be looped over by callers.
+
+In Python versions up to 2.1, the usual way to make ``for item in obj`` work is
+to define a :meth:`__getitem__` method that looks something like this::
+
+ def __getitem__(self, index):
+ return <next item>
+
+:meth:`__getitem__` is more properly used to define an indexing operation on an
+object so that you can write ``obj[5]`` to retrieve the sixth element. It's a
+bit misleading when you're using this only to support :keyword:`for` loops.
+Consider some file-like object that wants to be looped over; the *index*
+parameter is essentially meaningless, as the class probably assumes that a
+series of :meth:`__getitem__` calls will be made with *index* incrementing by
+one each time. In other words, the presence of the :meth:`__getitem__` method
+doesn't mean that using ``file[5]`` to randomly access the sixth element will
+work, though it really should.
+
+In Python 2.2, iteration can be implemented separately, and :meth:`__getitem__`
+methods can be limited to classes that really do support random access. The
+basic idea of iterators is simple. A new built-in function, :func:`iter(obj)`
+or ``iter(C, sentinel)``, is used to get an iterator. :func:`iter(obj)` returns
+an iterator for the object *obj*, while ``iter(C, sentinel)`` returns an
+iterator that will invoke the callable object *C* until it returns *sentinel* to
+signal that the iterator is done.
+
+Python classes can define an :meth:`__iter__` method, which should create and
+return a new iterator for the object; if the object is its own iterator, this
+method can just return ``self``. In particular, iterators will usually be their
+own iterators. Extension types implemented in C can implement a :attr:`tp_iter`
+function in order to return an iterator, and extension types that want to behave
+as iterators can define a :attr:`tp_iternext` function.
+
+So, after all this, what do iterators actually do? They have one required
+method, :meth:`next`, which takes no arguments and returns the next value. When
+there are no more values to be returned, calling :meth:`next` should raise the
+:exc:`StopIteration` exception. ::
+
+ >>> L = [1,2,3]
+ >>> i = iter(L)
+ >>> print i
+ <iterator object at 0x8116870>
+ >>> i.next()
+ 1
+ >>> i.next()
+ 2
+ >>> i.next()
+ 3
+ >>> i.next()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ StopIteration
+ >>>
+
+In 2.2, Python's :keyword:`for` statement no longer expects a sequence; it
+expects something for which :func:`iter` will return an iterator. For backward
+compatibility and convenience, an iterator is automatically constructed for
+sequences that don't implement :meth:`__iter__` or a :attr:`tp_iter` slot, so
+``for i in [1,2,3]`` will still work. Wherever the Python interpreter loops
+over a sequence, it's been changed to use the iterator protocol. This means you
+can do things like this::
+
+ >>> L = [1,2,3]
+ >>> i = iter(L)
+ >>> a,b,c = i
+ >>> a,b,c
+ (1, 2, 3)
+
+Iterator support has been added to some of Python's basic types. Calling
+:func:`iter` on a dictionary will return an iterator which loops over its keys::
+
+ >>> m = {'Jan': 1, 'Feb': 2, 'Mar': 3, 'Apr': 4, 'May': 5, 'Jun': 6,
+ ... 'Jul': 7, 'Aug': 8, 'Sep': 9, 'Oct': 10, 'Nov': 11, 'Dec': 12}
+ >>> for key in m: print key, m[key]
+ ...
+ Mar 3
+ Feb 2
+ Aug 8
+ Sep 9
+ May 5
+ Jun 6
+ Jul 7
+ Jan 1
+ Apr 4
+ Nov 11
+ Dec 12
+ Oct 10
+
+That's just the default behaviour. If you want to iterate over keys, values, or
+key/value pairs, you can explicitly call the :meth:`iterkeys`,
+:meth:`itervalues`, or :meth:`iteritems` methods to get an appropriate iterator.
+In a minor related change, the :keyword:`in` operator now works on dictionaries,
+so ``key in dict`` is now equivalent to ``dict.has_key(key)``.
+
+Files also provide an iterator, which calls the :meth:`readline` method until
+there are no more lines in the file. This means you can now read each line of a
+file using code like this::
+
+ for line in file:
+ # do something for each line
+ ...
+
+Note that you can only go forward in an iterator; there's no way to get the
+previous element, reset the iterator, or make a copy of it. An iterator object
+could provide such additional capabilities, but the iterator protocol only
+requires a :meth:`next` method.
+
+
+.. seealso::
+
+ :pep:`234` - Iterators
+ Written by Ka-Ping Yee and GvR; implemented by the Python Labs crew, mostly by
+ GvR and Tim Peters.
+
+.. % ======================================================================
+
+
+PEP 255: Simple Generators
+==========================
+
+Generators are another new feature, one that interacts with the introduction of
+iterators.
+
+You're doubtless familiar with how function calls work in Python or C. When you
+call a function, it gets a private namespace where its local variables are
+created. When the function reaches a :keyword:`return` statement, the local
+variables are destroyed and the resulting value is returned to the caller. A
+later call to the same function will get a fresh new set of local variables.
+But, what if the local variables weren't thrown away on exiting a function?
+What if you could later resume the function where it left off? This is what
+generators provide; they can be thought of as resumable functions.
+
+Here's the simplest example of a generator function::
+
+ def generate_ints(N):
+ for i in range(N):
+ yield i
+
+A new keyword, :keyword:`yield`, was introduced for generators. Any function
+containing a :keyword:`yield` statement is a generator function; this is
+detected by Python's bytecode compiler which compiles the function specially as
+a result. Because a new keyword was introduced, generators must be explicitly
+enabled in a module by including a ``from __future__ import generators``
+statement near the top of the module's source code. In Python 2.3 this
+statement will become unnecessary.
+
+When you call a generator function, it doesn't return a single value; instead it
+returns a generator object that supports the iterator protocol. On executing
+the :keyword:`yield` statement, the generator outputs the value of ``i``,
+similar to a :keyword:`return` statement. The big difference between
+:keyword:`yield` and a :keyword:`return` statement is that on reaching a
+:keyword:`yield` the generator's state of execution is suspended and local
+variables are preserved. On the next call to the generator's ``next()`` method,
+the function will resume executing immediately after the :keyword:`yield`
+statement. (For complicated reasons, the :keyword:`yield` statement isn't
+allowed inside the :keyword:`try` block of a :keyword:`try`...\
+:keyword:`finally` statement; read :pep:`255` for a full explanation of the
+interaction between :keyword:`yield` and exceptions.)
+
+Here's a sample usage of the :func:`generate_ints` generator::
+
+ >>> gen = generate_ints(3)
+ >>> gen
+ <generator object at 0x8117f90>
+ >>> gen.next()
+ 0
+ >>> gen.next()
+ 1
+ >>> gen.next()
+ 2
+ >>> gen.next()
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "<stdin>", line 2, in generate_ints
+ StopIteration
+
+You could equally write ``for i in generate_ints(5)``, or ``a,b,c =
+generate_ints(3)``.
+
+Inside a generator function, the :keyword:`return` statement can only be used
+without a value, and signals the end of the procession of values; afterwards the
+generator cannot return any further values. :keyword:`return` with a value, such
+as ``return 5``, is a syntax error inside a generator function. The end of the
+generator's results can also be indicated by raising :exc:`StopIteration`
+manually, or by just letting the flow of execution fall off the bottom of the
+function.
+
+You could achieve the effect of generators manually by writing your own class
+and storing all the local variables of the generator as instance variables. For
+example, returning a list of integers could be done by setting ``self.count`` to
+0, and having the :meth:`next` method increment ``self.count`` and return it.
+However, for a moderately complicated generator, writing a corresponding class
+would be much messier. :file:`Lib/test/test_generators.py` contains a number of
+more interesting examples. The simplest one implements an in-order traversal of
+a tree using generators recursively. ::
+
+ # A recursive generator that generates Tree leaves in in-order.
+ def inorder(t):
+ if t:
+ for x in inorder(t.left):
+ yield x
+ yield t.label
+ for x in inorder(t.right):
+ yield x
+
+Two other examples in :file:`Lib/test/test_generators.py` produce solutions for
+the N-Queens problem (placing $N$ queens on an $NxN$ chess board so that no
+queen threatens another) and the Knight's Tour (a route that takes a knight to
+every square of an $NxN$ chessboard without visiting any square twice).
+
+The idea of generators comes from other programming languages, especially Icon
+(http://www.cs.arizona.edu/icon/), where the idea of generators is central. In
+Icon, every expression and function call behaves like a generator. One example
+from "An Overview of the Icon Programming Language" at
+http://www.cs.arizona.edu/icon/docs/ipd266.htm gives an idea of what this looks
+like::
+
+ sentence := "Store it in the neighboring harbor"
+ if (i := find("or", sentence)) > 5 then write(i)
+
+In Icon the :func:`find` function returns the indexes at which the substring
+"or" is found: 3, 23, 33. In the :keyword:`if` statement, ``i`` is first
+assigned a value of 3, but 3 is less than 5, so the comparison fails, and Icon
+retries it with the second value of 23. 23 is greater than 5, so the comparison
+now succeeds, and the code prints the value 23 to the screen.
+
+Python doesn't go nearly as far as Icon in adopting generators as a central
+concept. Generators are considered a new part of the core Python language, but
+learning or using them isn't compulsory; if they don't solve any problems that
+you have, feel free to ignore them. One novel feature of Python's interface as
+compared to Icon's is that a generator's state is represented as a concrete
+object (the iterator) that can be passed around to other functions or stored in
+a data structure.
+
+
+.. seealso::
+
+ :pep:`255` - Simple Generators
+ Written by Neil Schemenauer, Tim Peters, Magnus Lie Hetland. Implemented mostly
+ by Neil Schemenauer and Tim Peters, with other fixes from the Python Labs crew.
+
+.. % ======================================================================
+
+
+PEP 237: Unifying Long Integers and Integers
+============================================
+
+In recent versions, the distinction between regular integers, which are 32-bit
+values on most machines, and long integers, which can be of arbitrary size, was
+becoming an annoyance. For example, on platforms that support files larger than
+``2**32`` bytes, the :meth:`tell` method of file objects has to return a long
+integer. However, there were various bits of Python that expected plain integers
+and would raise an error if a long integer was provided instead. For example,
+in Python 1.5, only regular integers could be used as a slice index, and
+``'abc'[1L:]`` would raise a :exc:`TypeError` exception with the message 'slice
+index must be int'.
+
+Python 2.2 will shift values from short to long integers as required. The 'L'
+suffix is no longer needed to indicate a long integer literal, as now the
+compiler will choose the appropriate type. (Using the 'L' suffix will be
+discouraged in future 2.x versions of Python, triggering a warning in Python
+2.4, and probably dropped in Python 3.0.) Many operations that used to raise an
+:exc:`OverflowError` will now return a long integer as their result. For
+example::
+
+ >>> 1234567890123
+ 1234567890123L
+ >>> 2 ** 64
+ 18446744073709551616L
+
+In most cases, integers and long integers will now be treated identically. You
+can still distinguish them with the :func:`type` built-in function, but that's
+rarely needed.
+
+
+.. seealso::
+
+ :pep:`237` - Unifying Long Integers and Integers
+ Written by Moshe Zadka and Guido van Rossum. Implemented mostly by Guido van
+ Rossum.
+
+.. % ======================================================================
+
+
+PEP 238: Changing the Division Operator
+=======================================
+
+The most controversial change in Python 2.2 heralds the start of an effort to
+fix an old design flaw that's been in Python from the beginning. Currently
+Python's division operator, ``/``, behaves like C's division operator when
+presented with two integer arguments: it returns an integer result that's
+truncated down when there would be a fractional part. For example, ``3/2`` is
+1, not 1.5, and ``(-1)/2`` is -1, not -0.5. This means that the results of
+divison can vary unexpectedly depending on the type of the two operands and
+because Python is dynamically typed, it can be difficult to determine the
+possible types of the operands.
+
+(The controversy is over whether this is *really* a design flaw, and whether
+it's worth breaking existing code to fix this. It's caused endless discussions
+on python-dev, and in July 2001 erupted into an storm of acidly sarcastic
+postings on :newsgroup:`comp.lang.python`. I won't argue for either side here
+and will stick to describing what's implemented in 2.2. Read :pep:`238` for a
+summary of arguments and counter-arguments.)
+
+Because this change might break code, it's being introduced very gradually.
+Python 2.2 begins the transition, but the switch won't be complete until Python
+3.0.
+
+First, I'll borrow some terminology from :pep:`238`. "True division" is the
+division that most non-programmers are familiar with: 3/2 is 1.5, 1/4 is 0.25,
+and so forth. "Floor division" is what Python's ``/`` operator currently does
+when given integer operands; the result is the floor of the value returned by
+true division. "Classic division" is the current mixed behaviour of ``/``; it
+returns the result of floor division when the operands are integers, and returns
+the result of true division when one of the operands is a floating-point number.
+
+Here are the changes 2.2 introduces:
+
+* A new operator, ``//``, is the floor division operator. (Yes, we know it looks
+ like C++'s comment symbol.) ``//`` *always* performs floor division no matter
+ what the types of its operands are, so ``1 // 2`` is 0 and ``1.0 // 2.0`` is
+ also 0.0.
+
+ ``//`` is always available in Python 2.2; you don't need to enable it using a
+ ``__future__`` statement.
+
+* By including a ``from __future__ import division`` in a module, the ``/``
+ operator will be changed to return the result of true division, so ``1/2`` is
+ 0.5. Without the ``__future__`` statement, ``/`` still means classic division.
+ The default meaning of ``/`` will not change until Python 3.0.
+
+* Classes can define methods called :meth:`__truediv__` and :meth:`__floordiv__`
+ to overload the two division operators. At the C level, there are also slots in
+ the :ctype:`PyNumberMethods` structure so extension types can define the two
+ operators.
+
+* Python 2.2 supports some command-line arguments for testing whether code will
+ works with the changed division semantics. Running python with :option:`-Q
+ warn` will cause a warning to be issued whenever division is applied to two
+ integers. You can use this to find code that's affected by the change and fix
+ it. By default, Python 2.2 will simply perform classic division without a
+ warning; the warning will be turned on by default in Python 2.3.
+
+
+.. seealso::
+
+ :pep:`238` - Changing the Division Operator
+ Written by Moshe Zadka and Guido van Rossum. Implemented by Guido van Rossum..
+
+.. % ======================================================================
+
+
+Unicode Changes
+===============
+
+Python's Unicode support has been enhanced a bit in 2.2. Unicode strings are
+usually stored as UCS-2, as 16-bit unsigned integers. Python 2.2 can also be
+compiled to use UCS-4, 32-bit unsigned integers, as its internal encoding by
+supplying :option:`--enable-unicode=ucs4` to the configure script. (It's also
+possible to specify :option:`--disable-unicode` to completely disable Unicode
+support.)
+
+When built to use UCS-4 (a "wide Python"), the interpreter can natively handle
+Unicode characters from U+000000 to U+110000, so the range of legal values for
+the :func:`unichr` function is expanded accordingly. Using an interpreter
+compiled to use UCS-2 (a "narrow Python"), values greater than 65535 will still
+cause :func:`unichr` to raise a :exc:`ValueError` exception. This is all
+described in :pep:`261`, "Support for 'wide' Unicode characters"; consult it for
+further details.
+
+Another change is simpler to explain. Since their introduction, Unicode strings
+have supported an :meth:`encode` method to convert the string to a selected
+encoding such as UTF-8 or Latin-1. A symmetric :meth:`decode([*encoding*])`
+method has been added to 8-bit strings (though not to Unicode strings) in 2.2.
+:meth:`decode` assumes that the string is in the specified encoding and decodes
+it, returning whatever is returned by the codec.
+
+Using this new feature, codecs have been added for tasks not directly related to
+Unicode. For example, codecs have been added for uu-encoding, MIME's base64
+encoding, and compression with the :mod:`zlib` module::
+
+ >>> s = """Here is a lengthy piece of redundant, overly verbose,
+ ... and repetitive text.
+ ... """
+ >>> data = s.encode('zlib')
+ >>> data
+ 'x\x9c\r\xc9\xc1\r\x80 \x10\x04\xc0?Ul...'
+ >>> data.decode('zlib')
+ 'Here is a lengthy piece of redundant, overly verbose,\nand repetitive text.\n'
+ >>> print s.encode('uu')
+ begin 666 <data>
+ M2&5R92!I<R!A(&QE;F=T:'D@<&EE8V4@;V8@<F5D=6YD86YT+"!O=F5R;'D@
+ >=F5R8F]S92P*86YD(')E<&5T:71I=F4@=&5X="X*
+
+ end
+ >>> "sheesh".encode('rot-13')
+ 'furrfu'
+
+To convert a class instance to Unicode, a :meth:`__unicode__` method can be
+defined by a class, analogous to :meth:`__str__`.
+
+:meth:`encode`, :meth:`decode`, and :meth:`__unicode__` were implemented by
+Marc-André Lemburg. The changes to support using UCS-4 internally were
+implemented by Fredrik Lundh and Martin von Löwis.
+
+
+.. seealso::
+
+ :pep:`261` - Support for 'wide' Unicode characters
+ Written by Paul Prescod.
+
+.. % ======================================================================
+
+
+PEP 227: Nested Scopes
+======================
+
+In Python 2.1, statically nested scopes were added as an optional feature, to be
+enabled by a ``from __future__ import nested_scopes`` directive. In 2.2 nested
+scopes no longer need to be specially enabled, and are now always present. The
+rest of this section is a copy of the description of nested scopes from my
+"What's New in Python 2.1" document; if you read it when 2.1 came out, you can
+skip the rest of this section.
+
+The largest change introduced in Python 2.1, and made complete in 2.2, is to
+Python's scoping rules. In Python 2.0, at any given time there are at most
+three namespaces used to look up variable names: local, module-level, and the
+built-in namespace. This often surprised people because it didn't match their
+intuitive expectations. For example, a nested recursive function definition
+doesn't work::
+
+ def f():
+ ...
+ def g(value):
+ ...
+ return g(value-1) + 1
+ ...
+
+The function :func:`g` will always raise a :exc:`NameError` exception, because
+the binding of the name ``g`` isn't in either its local namespace or in the
+module-level namespace. This isn't much of a problem in practice (how often do
+you recursively define interior functions like this?), but this also made using
+the :keyword:`lambda` statement clumsier, and this was a problem in practice.
+In code which uses :keyword:`lambda` you can often find local variables being
+copied by passing them as the default values of arguments. ::
+
+ def find(self, name):
+ "Return list of any entries equal to 'name'"
+ L = filter(lambda x, name=name: x == name,
+ self.list_attribute)
+ return L
+
+The readability of Python code written in a strongly functional style suffers
+greatly as a result.
+
+The most significant change to Python 2.2 is that static scoping has been added
+to the language to fix this problem. As a first effect, the ``name=name``
+default argument is now unnecessary in the above example. Put simply, when a
+given variable name is not assigned a value within a function (by an assignment,
+or the :keyword:`def`, :keyword:`class`, or :keyword:`import` statements),
+references to the variable will be looked up in the local namespace of the
+enclosing scope. A more detailed explanation of the rules, and a dissection of
+the implementation, can be found in the PEP.
+
+This change may cause some compatibility problems for code where the same
+variable name is used both at the module level and as a local variable within a
+function that contains further function definitions. This seems rather unlikely
+though, since such code would have been pretty confusing to read in the first
+place.
+
+One side effect of the change is that the ``from module import *`` and
+:keyword:`exec` statements have been made illegal inside a function scope under
+certain conditions. The Python reference manual has said all along that ``from
+module import *`` is only legal at the top level of a module, but the CPython
+interpreter has never enforced this before. As part of the implementation of
+nested scopes, the compiler which turns Python source into bytecodes has to
+generate different code to access variables in a containing scope. ``from
+module import *`` and :keyword:`exec` make it impossible for the compiler to
+figure this out, because they add names to the local namespace that are
+unknowable at compile time. Therefore, if a function contains function
+definitions or :keyword:`lambda` expressions with free variables, the compiler
+will flag this by raising a :exc:`SyntaxError` exception.
+
+To make the preceding explanation a bit clearer, here's an example::
+
+ x = 1
+ def f():
+ # The next line is a syntax error
+ exec 'x=2'
+ def g():
+ return x
+
+Line 4 containing the :keyword:`exec` statement is a syntax error, since
+:keyword:`exec` would define a new local variable named ``x`` whose value should
+be accessed by :func:`g`.
+
+This shouldn't be much of a limitation, since :keyword:`exec` is rarely used in
+most Python code (and when it is used, it's often a sign of a poor design
+anyway).
+
+
+.. seealso::
+
+ :pep:`227` - Statically Nested Scopes
+ Written and implemented by Jeremy Hylton.
+
+.. % ======================================================================
+
+
+New and Improved Modules
+========================
+
+* The :mod:`xmlrpclib` module was contributed to the standard library by Fredrik
+ Lundh, providing support for writing XML-RPC clients. XML-RPC is a simple
+ remote procedure call protocol built on top of HTTP and XML. For example, the
+ following snippet retrieves a list of RSS channels from the O'Reilly Network,
+ and then lists the recent headlines for one channel::
+
+ import xmlrpclib
+ s = xmlrpclib.Server(
+ 'http://www.oreillynet.com/meerkat/xml-rpc/server.php')
+ channels = s.meerkat.getChannels()
+ # channels is a list of dictionaries, like this:
+ # [{'id': 4, 'title': 'Freshmeat Daily News'}
+ # {'id': 190, 'title': '32Bits Online'},
+ # {'id': 4549, 'title': '3DGamers'}, ... ]
+
+ # Get the items for one channel
+ items = s.meerkat.getItems( {'channel': 4} )
+
+ # 'items' is another list of dictionaries, like this:
+ # [{'link': 'http://freshmeat.net/releases/52719/',
+ # 'description': 'A utility which converts HTML to XSL FO.',
+ # 'title': 'html2fo 0.3 (Default)'}, ... ]
+
+ The :mod:`SimpleXMLRPCServer` module makes it easy to create straightforward
+ XML-RPC servers. See http://www.xmlrpc.com/ for more information about XML-RPC.
+
+* The new :mod:`hmac` module implements the HMAC algorithm described by
+ :rfc:`2104`. (Contributed by Gerhard Häring.)
+
+* Several functions that originally returned lengthy tuples now return pseudo-
+ sequences that still behave like tuples but also have mnemonic attributes such
+ as memberst_mtime or :attr:`tm_year`. The enhanced functions include
+ :func:`stat`, :func:`fstat`, :func:`statvfs`, and :func:`fstatvfs` in the
+ :mod:`os` module, and :func:`localtime`, :func:`gmtime`, and :func:`strptime` in
+ the :mod:`time` module.
+
+ For example, to obtain a file's size using the old tuples, you'd end up writing
+ something like ``file_size = os.stat(filename)[stat.ST_SIZE]``, but now this can
+ be written more clearly as ``file_size = os.stat(filename).st_size``.
+
+ The original patch for this feature was contributed by Nick Mathewson.
+
+* The Python profiler has been extensively reworked and various errors in its
+ output have been corrected. (Contributed by Fred L. Drake, Jr. and Tim Peters.)
+
+* The :mod:`socket` module can be compiled to support IPv6; specify the
+ :option:`--enable-ipv6` option to Python's configure script. (Contributed by
+ Jun-ichiro "itojun" Hagino.)
+
+* Two new format characters were added to the :mod:`struct` module for 64-bit
+ integers on platforms that support the C :ctype:`long long` type. ``q`` is for
+ a signed 64-bit integer, and ``Q`` is for an unsigned one. The value is
+ returned in Python's long integer type. (Contributed by Tim Peters.)
+
+* In the interpreter's interactive mode, there's a new built-in function
+ :func:`help` that uses the :mod:`pydoc` module introduced in Python 2.1 to
+ provide interactive help. ``help(object)`` displays any available help text
+ about *object*. :func:`help` with no argument puts you in an online help
+ utility, where you can enter the names of functions, classes, or modules to read
+ their help text. (Contributed by Guido van Rossum, using Ka-Ping Yee's
+ :mod:`pydoc` module.)
+
+* Various bugfixes and performance improvements have been made to the SRE engine
+ underlying the :mod:`re` module. For example, the :func:`re.sub` and
+ :func:`re.split` functions have been rewritten in C. Another contributed patch
+ speeds up certain Unicode character ranges by a factor of two, and a new
+ :meth:`finditer` method that returns an iterator over all the non-overlapping
+ matches in a given string. (SRE is maintained by Fredrik Lundh. The
+ BIGCHARSET patch was contributed by Martin von Löwis.)
+
+* The :mod:`smtplib` module now supports :rfc:`2487`, "Secure SMTP over TLS", so
+ it's now possible to encrypt the SMTP traffic between a Python program and the
+ mail transport agent being handed a message. :mod:`smtplib` also supports SMTP
+ authentication. (Contributed by Gerhard Häring.)
+
+* The :mod:`imaplib` module, maintained by Piers Lauder, has support for several
+ new extensions: the NAMESPACE extension defined in :rfc:`2342`, SORT, GETACL and
+ SETACL. (Contributed by Anthony Baxter and Michel Pelletier.)
+
+* The :mod:`rfc822` module's parsing of email addresses is now compliant with
+ :rfc:`2822`, an update to :rfc:`822`. (The module's name is *not* going to be
+ changed to ``rfc2822``.) A new package, :mod:`email`, has also been added for
+ parsing and generating e-mail messages. (Contributed by Barry Warsaw, and
+ arising out of his work on Mailman.)
+
+* The :mod:`difflib` module now contains a new :class:`Differ` class for
+ producing human-readable lists of changes (a "delta") between two sequences of
+ lines of text. There are also two generator functions, :func:`ndiff` and
+ :func:`restore`, which respectively return a delta from two sequences, or one of
+ the original sequences from a delta. (Grunt work contributed by David Goodger,
+ from ndiff.py code by Tim Peters who then did the generatorization.)
+
+* New constants :const:`ascii_letters`, :const:`ascii_lowercase`, and
+ :const:`ascii_uppercase` were added to the :mod:`string` module. There were
+ several modules in the standard library that used :const:`string.letters` to
+ mean the ranges A-Za-z, but that assumption is incorrect when locales are in
+ use, because :const:`string.letters` varies depending on the set of legal
+ characters defined by the current locale. The buggy modules have all been fixed
+ to use :const:`ascii_letters` instead. (Reported by an unknown person; fixed by
+ Fred L. Drake, Jr.)
+
+* The :mod:`mimetypes` module now makes it easier to use alternative MIME-type
+ databases by the addition of a :class:`MimeTypes` class, which takes a list of
+ filenames to be parsed. (Contributed by Fred L. Drake, Jr.)
+
+* A :class:`Timer` class was added to the :mod:`threading` module that allows
+ scheduling an activity to happen at some future time. (Contributed by Itamar
+ Shtull-Trauring.)
+
+.. % ======================================================================
+
+
+Interpreter Changes and Fixes
+=============================
+
+Some of the changes only affect people who deal with the Python interpreter at
+the C level because they're writing Python extension modules, embedding the
+interpreter, or just hacking on the interpreter itself. If you only write Python
+code, none of the changes described here will affect you very much.
+
+* Profiling and tracing functions can now be implemented in C, which can operate
+ at much higher speeds than Python-based functions and should reduce the overhead
+ of profiling and tracing. This will be of interest to authors of development
+ environments for Python. Two new C functions were added to Python's API,
+ :cfunc:`PyEval_SetProfile` and :cfunc:`PyEval_SetTrace`. The existing
+ :func:`sys.setprofile` and :func:`sys.settrace` functions still exist, and have
+ simply been changed to use the new C-level interface. (Contributed by Fred L.
+ Drake, Jr.)
+
+* Another low-level API, primarily of interest to implementors of Python
+ debuggers and development tools, was added. :cfunc:`PyInterpreterState_Head` and
+ :cfunc:`PyInterpreterState_Next` let a caller walk through all the existing
+ interpreter objects; :cfunc:`PyInterpreterState_ThreadHead` and
+ :cfunc:`PyThreadState_Next` allow looping over all the thread states for a given
+ interpreter. (Contributed by David Beazley.)
+
+* The C-level interface to the garbage collector has been changed to make it
+ easier to write extension types that support garbage collection and to debug
+ misuses of the functions. Various functions have slightly different semantics,
+ so a bunch of functions had to be renamed. Extensions that use the old API will
+ still compile but will *not* participate in garbage collection, so updating them
+ for 2.2 should be considered fairly high priority.
+
+ To upgrade an extension module to the new API, perform the following steps:
+
+* Rename :cfunc:`Py_TPFLAGS_GC` to :cfunc:`PyTPFLAGS_HAVE_GC`.
+
+* Use :cfunc:`PyObject_GC_New` or :cfunc:`PyObject_GC_NewVar` to allocate
+ objects, and :cfunc:`PyObject_GC_Del` to deallocate them.
+
+* Rename :cfunc:`PyObject_GC_Init` to :cfunc:`PyObject_GC_Track` and
+ :cfunc:`PyObject_GC_Fini` to :cfunc:`PyObject_GC_UnTrack`.
+
+* Remove :cfunc:`PyGC_HEAD_SIZE` from object size calculations.
+
+* Remove calls to :cfunc:`PyObject_AS_GC` and :cfunc:`PyObject_FROM_GC`.
+
+* A new ``et`` format sequence was added to :cfunc:`PyArg_ParseTuple`; ``et``
+ takes both a parameter and an encoding name, and converts the parameter to the
+ given encoding if the parameter turns out to be a Unicode string, or leaves it
+ alone if it's an 8-bit string, assuming it to already be in the desired
+ encoding. This differs from the ``es`` format character, which assumes that
+ 8-bit strings are in Python's default ASCII encoding and converts them to the
+ specified new encoding. (Contributed by M.-A. Lemburg, and used for the MBCS
+ support on Windows described in the following section.)
+
+* A different argument parsing function, :cfunc:`PyArg_UnpackTuple`, has been
+ added that's simpler and presumably faster. Instead of specifying a format
+ string, the caller simply gives the minimum and maximum number of arguments
+ expected, and a set of pointers to :ctype:`PyObject\*` variables that will be
+ filled in with argument values.
+
+* Two new flags :const:`METH_NOARGS` and :const:`METH_O` are available in method
+ definition tables to simplify implementation of methods with no arguments or a
+ single untyped argument. Calling such methods is more efficient than calling a
+ corresponding method that uses :const:`METH_VARARGS`. Also, the old
+ :const:`METH_OLDARGS` style of writing C methods is now officially deprecated.
+
+* Two new wrapper functions, :cfunc:`PyOS_snprintf` and :cfunc:`PyOS_vsnprintf`
+ were added to provide cross-platform implementations for the relatively new
+ :cfunc:`snprintf` and :cfunc:`vsnprintf` C lib APIs. In contrast to the standard
+ :cfunc:`sprintf` and :cfunc:`vsprintf` functions, the Python versions check the
+ bounds of the buffer used to protect against buffer overruns. (Contributed by
+ M.-A. Lemburg.)
+
+* The :cfunc:`_PyTuple_Resize` function has lost an unused parameter, so now it
+ takes 2 parameters instead of 3. The third argument was never used, and can
+ simply be discarded when porting code from earlier versions to Python 2.2.
+
+.. % ======================================================================
+
+
+Other Changes and Fixes
+=======================
+
+As usual there were a bunch of other improvements and bugfixes scattered
+throughout the source tree. A search through the CVS change logs finds there
+were 527 patches applied and 683 bugs fixed between Python 2.1 and 2.2; 2.2.1
+applied 139 patches and fixed 143 bugs; 2.2.2 applied 106 patches and fixed 82
+bugs. These figures are likely to be underestimates.
+
+Some of the more notable changes are:
+
+* The code for the MacOS port for Python, maintained by Jack Jansen, is now kept
+ in the main Python CVS tree, and many changes have been made to support MacOS X.
+
+ The most significant change is the ability to build Python as a framework,
+ enabled by supplying the :option:`--enable-framework` option to the configure
+ script when compiling Python. According to Jack Jansen, "This installs a self-
+ contained Python installation plus the OS X framework "glue" into
+ :file:`/Library/Frameworks/Python.framework` (or another location of choice).
+ For now there is little immediate added benefit to this (actually, there is the
+ disadvantage that you have to change your PATH to be able to find Python), but
+ it is the basis for creating a full-blown Python application, porting the
+ MacPython IDE, possibly using Python as a standard OSA scripting language and
+ much more."
+
+ Most of the MacPython toolbox modules, which interface to MacOS APIs such as
+ windowing, QuickTime, scripting, etc. have been ported to OS X, but they've been
+ left commented out in :file:`setup.py`. People who want to experiment with
+ these modules can uncomment them manually.
+
+ .. % Jack's original comments:
+ .. % The main change is the possibility to build Python as a
+ .. % framework. This installs a self-contained Python installation plus the
+ .. % OSX framework "glue" into /Library/Frameworks/Python.framework (or
+ .. % another location of choice). For now there is little immedeate added
+ .. % benefit to this (actually, there is the disadvantage that you have to
+ .. % change your PATH to be able to find Python), but it is the basis for
+ .. % creating a fullblown Python application, porting the MacPython IDE,
+ .. % possibly using Python as a standard OSA scripting language and much
+ .. % more. You enable this with "configure --enable-framework".
+ .. % The other change is that most MacPython toolbox modules, which
+ .. % interface to all the MacOS APIs such as windowing, quicktime,
+ .. % scripting, etc. have been ported. Again, most of these are not of
+ .. % immedeate use, as they need a full application to be really useful, so
+ .. % they have been commented out in setup.py. People wanting to experiment
+ .. % can uncomment them. Gestalt and Internet Config modules are enabled by
+ .. % default.
+
+* Keyword arguments passed to builtin functions that don't take them now cause a
+ :exc:`TypeError` exception to be raised, with the message "*function* takes no
+ keyword arguments".
+
+* Weak references, added in Python 2.1 as an extension module, are now part of
+ the core because they're used in the implementation of new-style classes. The
+ :exc:`ReferenceError` exception has therefore moved from the :mod:`weakref`
+ module to become a built-in exception.
+
+* A new script, :file:`Tools/scripts/cleanfuture.py` by Tim Peters,
+ automatically removes obsolete ``__future__`` statements from Python source
+ code.
+
+* An additional *flags* argument has been added to the built-in function
+ :func:`compile`, so the behaviour of ``__future__`` statements can now be
+ correctly observed in simulated shells, such as those presented by IDLE and
+ other development environments. This is described in :pep:`264`. (Contributed
+ by Michael Hudson.)
+
+* The new license introduced with Python 1.6 wasn't GPL-compatible. This is
+ fixed by some minor textual changes to the 2.2 license, so it's now legal to
+ embed Python inside a GPLed program again. Note that Python itself is not
+ GPLed, but instead is under a license that's essentially equivalent to the BSD
+ license, same as it always was. The license changes were also applied to the
+ Python 2.0.1 and 2.1.1 releases.
+
+* When presented with a Unicode filename on Windows, Python will now convert it
+ to an MBCS encoded string, as used by the Microsoft file APIs. As MBCS is
+ explicitly used by the file APIs, Python's choice of ASCII as the default
+ encoding turns out to be an annoyance. On Unix, the locale's character set is
+ used if :func:`locale.nl_langinfo(CODESET)` is available. (Windows support was
+ contributed by Mark Hammond with assistance from Marc-André Lemburg. Unix
+ support was added by Martin von Löwis.)
+
+* Large file support is now enabled on Windows. (Contributed by Tim Peters.)
+
+* The :file:`Tools/scripts/ftpmirror.py` script now parses a :file:`.netrc`
+ file, if you have one. (Contributed by Mike Romberg.)
+
+* Some features of the object returned by the :func:`xrange` function are now
+ deprecated, and trigger warnings when they're accessed; they'll disappear in
+ Python 2.3. :class:`xrange` objects tried to pretend they were full sequence
+ types by supporting slicing, sequence multiplication, and the :keyword:`in`
+ operator, but these features were rarely used and therefore buggy. The
+ :meth:`tolist` method and the :attr:`start`, :attr:`stop`, and :attr:`step`
+ attributes are also being deprecated. At the C level, the fourth argument to
+ the :cfunc:`PyRange_New` function, ``repeat``, has also been deprecated.
+
+* There were a bunch of patches to the dictionary implementation, mostly to fix
+ potential core dumps if a dictionary contains objects that sneakily changed
+ their hash value, or mutated the dictionary they were contained in. For a while
+ python-dev fell into a gentle rhythm of Michael Hudson finding a case that
+ dumped core, Tim Peters fixing the bug, Michael finding another case, and round
+ and round it went.
+
+* On Windows, Python can now be compiled with Borland C thanks to a number of
+ patches contributed by Stephen Hansen, though the result isn't fully functional
+ yet. (But this *is* progress...)
+
+* Another Windows enhancement: Wise Solutions generously offered PythonLabs use
+ of their InstallerMaster 8.1 system. Earlier PythonLabs Windows installers used
+ Wise 5.0a, which was beginning to show its age. (Packaged up by Tim Peters.)
+
+* Files ending in ``.pyw`` can now be imported on Windows. ``.pyw`` is a
+ Windows-only thing, used to indicate that a script needs to be run using
+ PYTHONW.EXE instead of PYTHON.EXE in order to prevent a DOS console from popping
+ up to display the output. This patch makes it possible to import such scripts,
+ in case they're also usable as modules. (Implemented by David Bolen.)
+
+* On platforms where Python uses the C :cfunc:`dlopen` function to load
+ extension modules, it's now possible to set the flags used by :cfunc:`dlopen`
+ using the :func:`sys.getdlopenflags` and :func:`sys.setdlopenflags` functions.
+ (Contributed by Bram Stolk.)
+
+* The :func:`pow` built-in function no longer supports 3 arguments when
+ floating-point numbers are supplied. ``pow(x, y, z)`` returns ``(x**y) % z``,
+ but this is never useful for floating point numbers, and the final result varies
+ unpredictably depending on the platform. A call such as ``pow(2.0, 8.0, 7.0)``
+ will now raise a :exc:`TypeError` exception.
+
+.. % ======================================================================
+
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: Fred Bremmer,
+Keith Briggs, Andrew Dalke, Fred L. Drake, Jr., Carel Fellinger, David Goodger,
+Mark Hammond, Stephen Hansen, Michael Hudson, Jack Jansen, Marc-André Lemburg,
+Martin von Löwis, Fredrik Lundh, Michael McLay, Nick Mathewson, Paul Moore,
+Gustavo Niemeyer, Don O'Donnell, Joonas Paalasma, Tim Peters, Jens Quade, Tom
+Reinhardt, Neil Schemenauer, Guido van Rossum, Greg Ward, Edward Welbourne.
+
diff --git a/Doc/whatsnew/2.3.rst b/Doc/whatsnew/2.3.rst
new file mode 100644
index 0000000000..7dd49306bb
--- /dev/null
+++ b/Doc/whatsnew/2.3.rst
@@ -0,0 +1,2084 @@
+****************************
+ What's New in Python 2.3
+****************************
+
+:Author: A.M. Kuchling
+
+.. |release| replace:: 1.01
+
+.. % $Id: whatsnew23.tex 55005 2007-04-27 19:54:29Z guido.van.rossum $
+
+This article explains the new features in Python 2.3. Python 2.3 was released
+on July 29, 2003.
+
+The main themes for Python 2.3 are polishing some of the features added in 2.2,
+adding various small but useful enhancements to the core language, and expanding
+the standard library. The new object model introduced in the previous version
+has benefited from 18 months of bugfixes and from optimization efforts that have
+improved the performance of new-style classes. A few new built-in functions
+have been added such as :func:`sum` and :func:`enumerate`. The :keyword:`in`
+operator can now be used for substring searches (e.g. ``"ab" in "abc"`` returns
+:const:`True`).
+
+Some of the many new library features include Boolean, set, heap, and date/time
+data types, the ability to import modules from ZIP-format archives, metadata
+support for the long-awaited Python catalog, an updated version of IDLE, and
+modules for logging messages, wrapping text, parsing CSV files, processing
+command-line options, using BerkeleyDB databases... the list of new and
+enhanced modules is lengthy.
+
+This article doesn't attempt to provide a complete specification of the new
+features, but instead provides a convenient overview. For full details, you
+should refer to the documentation for Python 2.3, such as the Python Library
+Reference and the Python Reference Manual. If you want to understand the
+complete implementation and design rationale, refer to the PEP for a particular
+new feature.
+
+.. % ======================================================================
+
+
+PEP 218: A Standard Set Datatype
+================================
+
+The new :mod:`sets` module contains an implementation of a set datatype. The
+:class:`Set` class is for mutable sets, sets that can have members added and
+removed. The :class:`ImmutableSet` class is for sets that can't be modified,
+and instances of :class:`ImmutableSet` can therefore be used as dictionary keys.
+Sets are built on top of dictionaries, so the elements within a set must be
+hashable.
+
+Here's a simple example::
+
+ >>> import sets
+ >>> S = sets.Set([1,2,3])
+ >>> S
+ Set([1, 2, 3])
+ >>> 1 in S
+ True
+ >>> 0 in S
+ False
+ >>> S.add(5)
+ >>> S.remove(3)
+ >>> S
+ Set([1, 2, 5])
+ >>>
+
+The union and intersection of sets can be computed with the :meth:`union` and
+:meth:`intersection` methods; an alternative notation uses the bitwise operators
+``&`` and ``|``. Mutable sets also have in-place versions of these methods,
+:meth:`union_update` and :meth:`intersection_update`. ::
+
+ >>> S1 = sets.Set([1,2,3])
+ >>> S2 = sets.Set([4,5,6])
+ >>> S1.union(S2)
+ Set([1, 2, 3, 4, 5, 6])
+ >>> S1 | S2 # Alternative notation
+ Set([1, 2, 3, 4, 5, 6])
+ >>> S1.intersection(S2)
+ Set([])
+ >>> S1 & S2 # Alternative notation
+ Set([])
+ >>> S1.union_update(S2)
+ >>> S1
+ Set([1, 2, 3, 4, 5, 6])
+ >>>
+
+It's also possible to take the symmetric difference of two sets. This is the
+set of all elements in the union that aren't in the intersection. Another way
+of putting it is that the symmetric difference contains all elements that are in
+exactly one set. Again, there's an alternative notation (``^``), and an in-
+place version with the ungainly name :meth:`symmetric_difference_update`. ::
+
+ >>> S1 = sets.Set([1,2,3,4])
+ >>> S2 = sets.Set([3,4,5,6])
+ >>> S1.symmetric_difference(S2)
+ Set([1, 2, 5, 6])
+ >>> S1 ^ S2
+ Set([1, 2, 5, 6])
+ >>>
+
+There are also :meth:`issubset` and :meth:`issuperset` methods for checking
+whether one set is a subset or superset of another::
+
+ >>> S1 = sets.Set([1,2,3])
+ >>> S2 = sets.Set([2,3])
+ >>> S2.issubset(S1)
+ True
+ >>> S1.issubset(S2)
+ False
+ >>> S1.issuperset(S2)
+ True
+ >>>
+
+
+.. seealso::
+
+ :pep:`218` - Adding a Built-In Set Object Type
+ PEP written by Greg V. Wilson. Implemented by Greg V. Wilson, Alex Martelli, and
+ GvR.
+
+.. % ======================================================================
+
+
+.. _section-generators:
+
+PEP 255: Simple Generators
+==========================
+
+In Python 2.2, generators were added as an optional feature, to be enabled by a
+``from __future__ import generators`` directive. In 2.3 generators no longer
+need to be specially enabled, and are now always present; this means that
+:keyword:`yield` is now always a keyword. The rest of this section is a copy of
+the description of generators from the "What's New in Python 2.2" document; if
+you read it back when Python 2.2 came out, you can skip the rest of this
+section.
+
+You're doubtless familiar with how function calls work in Python or C. When you
+call a function, it gets a private namespace where its local variables are
+created. When the function reaches a :keyword:`return` statement, the local
+variables are destroyed and the resulting value is returned to the caller. A
+later call to the same function will get a fresh new set of local variables.
+But, what if the local variables weren't thrown away on exiting a function?
+What if you could later resume the function where it left off? This is what
+generators provide; they can be thought of as resumable functions.
+
+Here's the simplest example of a generator function::
+
+ def generate_ints(N):
+ for i in range(N):
+ yield i
+
+A new keyword, :keyword:`yield`, was introduced for generators. Any function
+containing a :keyword:`yield` statement is a generator function; this is
+detected by Python's bytecode compiler which compiles the function specially as
+a result.
+
+When you call a generator function, it doesn't return a single value; instead it
+returns a generator object that supports the iterator protocol. On executing
+the :keyword:`yield` statement, the generator outputs the value of ``i``,
+similar to a :keyword:`return` statement. The big difference between
+:keyword:`yield` and a :keyword:`return` statement is that on reaching a
+:keyword:`yield` the generator's state of execution is suspended and local
+variables are preserved. On the next call to the generator's ``.next()``
+method, the function will resume executing immediately after the
+:keyword:`yield` statement. (For complicated reasons, the :keyword:`yield`
+statement isn't allowed inside the :keyword:`try` block of a :keyword:`try`...\
+:keyword:`finally` statement; read :pep:`255` for a full explanation of the
+interaction between :keyword:`yield` and exceptions.)
+
+Here's a sample usage of the :func:`generate_ints` generator::
+
+ >>> gen = generate_ints(3)
+ >>> gen
+ <generator object at 0x8117f90>
+ >>> gen.next()
+ 0
+ >>> gen.next()
+ 1
+ >>> gen.next()
+ 2
+ >>> gen.next()
+ Traceback (most recent call last):
+ File "stdin", line 1, in ?
+ File "stdin", line 2, in generate_ints
+ StopIteration
+
+You could equally write ``for i in generate_ints(5)``, or ``a,b,c =
+generate_ints(3)``.
+
+Inside a generator function, the :keyword:`return` statement can only be used
+without a value, and signals the end of the procession of values; afterwards the
+generator cannot return any further values. :keyword:`return` with a value, such
+as ``return 5``, is a syntax error inside a generator function. The end of the
+generator's results can also be indicated by raising :exc:`StopIteration`
+manually, or by just letting the flow of execution fall off the bottom of the
+function.
+
+You could achieve the effect of generators manually by writing your own class
+and storing all the local variables of the generator as instance variables. For
+example, returning a list of integers could be done by setting ``self.count`` to
+0, and having the :meth:`next` method increment ``self.count`` and return it.
+However, for a moderately complicated generator, writing a corresponding class
+would be much messier. :file:`Lib/test/test_generators.py` contains a number of
+more interesting examples. The simplest one implements an in-order traversal of
+a tree using generators recursively. ::
+
+ # A recursive generator that generates Tree leaves in in-order.
+ def inorder(t):
+ if t:
+ for x in inorder(t.left):
+ yield x
+ yield t.label
+ for x in inorder(t.right):
+ yield x
+
+Two other examples in :file:`Lib/test/test_generators.py` produce solutions for
+the N-Queens problem (placing $N$ queens on an $NxN$ chess board so that no
+queen threatens another) and the Knight's Tour (a route that takes a knight to
+every square of an $NxN$ chessboard without visiting any square twice).
+
+The idea of generators comes from other programming languages, especially Icon
+(http://www.cs.arizona.edu/icon/), where the idea of generators is central. In
+Icon, every expression and function call behaves like a generator. One example
+from "An Overview of the Icon Programming Language" at
+http://www.cs.arizona.edu/icon/docs/ipd266.htm gives an idea of what this looks
+like::
+
+ sentence := "Store it in the neighboring harbor"
+ if (i := find("or", sentence)) > 5 then write(i)
+
+In Icon the :func:`find` function returns the indexes at which the substring
+"or" is found: 3, 23, 33. In the :keyword:`if` statement, ``i`` is first
+assigned a value of 3, but 3 is less than 5, so the comparison fails, and Icon
+retries it with the second value of 23. 23 is greater than 5, so the comparison
+now succeeds, and the code prints the value 23 to the screen.
+
+Python doesn't go nearly as far as Icon in adopting generators as a central
+concept. Generators are considered part of the core Python language, but
+learning or using them isn't compulsory; if they don't solve any problems that
+you have, feel free to ignore them. One novel feature of Python's interface as
+compared to Icon's is that a generator's state is represented as a concrete
+object (the iterator) that can be passed around to other functions or stored in
+a data structure.
+
+
+.. seealso::
+
+ :pep:`255` - Simple Generators
+ Written by Neil Schemenauer, Tim Peters, Magnus Lie Hetland. Implemented mostly
+ by Neil Schemenauer and Tim Peters, with other fixes from the Python Labs crew.
+
+.. % ======================================================================
+
+
+.. _section-encodings:
+
+PEP 263: Source Code Encodings
+==============================
+
+Python source files can now be declared as being in different character set
+encodings. Encodings are declared by including a specially formatted comment in
+the first or second line of the source file. For example, a UTF-8 file can be
+declared with::
+
+ #!/usr/bin/env python
+ # -*- coding: UTF-8 -*-
+
+Without such an encoding declaration, the default encoding used is 7-bit ASCII.
+Executing or importing modules that contain string literals with 8-bit
+characters and have no encoding declaration will result in a
+:exc:`DeprecationWarning` being signalled by Python 2.3; in 2.4 this will be a
+syntax error.
+
+The encoding declaration only affects Unicode string literals, which will be
+converted to Unicode using the specified encoding. Note that Python identifiers
+are still restricted to ASCII characters, so you can't have variable names that
+use characters outside of the usual alphanumerics.
+
+
+.. seealso::
+
+ :pep:`263` - Defining Python Source Code Encodings
+ Written by Marc-André Lemburg and Martin von Löwis; implemented by Suzuki Hisao
+ and Martin von Löwis.
+
+.. % ======================================================================
+
+
+PEP 273: Importing Modules from ZIP Archives
+============================================
+
+The new :mod:`zipimport` module adds support for importing modules from a ZIP-
+format archive. You don't need to import the module explicitly; it will be
+automatically imported if a ZIP archive's filename is added to ``sys.path``.
+For example::
+
+ amk@nyman:~/src/python$ unzip -l /tmp/example.zip
+ Archive: /tmp/example.zip
+ Length Date Time Name
+ -------- ---- ---- ----
+ 8467 11-26-02 22:30 jwzthreading.py
+ -------- -------
+ 8467 1 file
+ amk@nyman:~/src/python$ ./python
+ Python 2.3 (#1, Aug 1 2003, 19:54:32)
+ >>> import sys
+ >>> sys.path.insert(0, '/tmp/example.zip') # Add .zip file to front of path
+ >>> import jwzthreading
+ >>> jwzthreading.__file__
+ '/tmp/example.zip/jwzthreading.py'
+ >>>
+
+An entry in ``sys.path`` can now be the filename of a ZIP archive. The ZIP
+archive can contain any kind of files, but only files named :file:`\*.py`,
+:file:`\*.pyc`, or :file:`\*.pyo` can be imported. If an archive only contains
+:file:`\*.py` files, Python will not attempt to modify the archive by adding the
+corresponding :file:`\*.pyc` file, meaning that if a ZIP archive doesn't contain
+:file:`\*.pyc` files, importing may be rather slow.
+
+A path within the archive can also be specified to only import from a
+subdirectory; for example, the path :file:`/tmp/example.zip/lib/` would only
+import from the :file:`lib/` subdirectory within the archive.
+
+
+.. seealso::
+
+ :pep:`273` - Import Modules from Zip Archives
+ Written by James C. Ahlstrom, who also provided an implementation. Python 2.3
+ follows the specification in :pep:`273`, but uses an implementation written by
+ Just van Rossum that uses the import hooks described in :pep:`302`. See section
+ :ref:`section-pep302` for a description of the new import hooks.
+
+.. % ======================================================================
+
+
+PEP 277: Unicode file name support for Windows NT
+=================================================
+
+On Windows NT, 2000, and XP, the system stores file names as Unicode strings.
+Traditionally, Python has represented file names as byte strings, which is
+inadequate because it renders some file names inaccessible.
+
+Python now allows using arbitrary Unicode strings (within the limitations of the
+file system) for all functions that expect file names, most notably the
+:func:`open` built-in function. If a Unicode string is passed to
+:func:`os.listdir`, Python now returns a list of Unicode strings. A new
+function, :func:`os.getcwdu`, returns the current directory as a Unicode string.
+
+Byte strings still work as file names, and on Windows Python will transparently
+convert them to Unicode using the ``mbcs`` encoding.
+
+Other systems also allow Unicode strings as file names but convert them to byte
+strings before passing them to the system, which can cause a :exc:`UnicodeError`
+to be raised. Applications can test whether arbitrary Unicode strings are
+supported as file names by checking :attr:`os.path.supports_unicode_filenames`,
+a Boolean value.
+
+Under MacOS, :func:`os.listdir` may now return Unicode filenames.
+
+
+.. seealso::
+
+ :pep:`277` - Unicode file name support for Windows NT
+ Written by Neil Hodgson; implemented by Neil Hodgson, Martin von Löwis, and Mark
+ Hammond.
+
+.. % ======================================================================
+
+
+PEP 278: Universal Newline Support
+==================================
+
+The three major operating systems used today are Microsoft Windows, Apple's
+Macintosh OS, and the various Unix derivatives. A minor irritation of cross-
+platform work is that these three platforms all use different characters to
+mark the ends of lines in text files. Unix uses the linefeed (ASCII character
+10), MacOS uses the carriage return (ASCII character 13), and Windows uses a
+two-character sequence of a carriage return plus a newline.
+
+Python's file objects can now support end of line conventions other than the one
+followed by the platform on which Python is running. Opening a file with the
+mode ``'U'`` or ``'rU'`` will open a file for reading in universal newline mode.
+All three line ending conventions will be translated to a ``'\n'`` in the
+strings returned by the various file methods such as :meth:`read` and
+:meth:`readline`.
+
+Universal newline support is also used when importing modules and when executing
+a file with the :func:`execfile` function. This means that Python modules can
+be shared between all three operating systems without needing to convert the
+line-endings.
+
+This feature can be disabled when compiling Python by specifying the
+:option:`--without-universal-newlines` switch when running Python's
+:program:`configure` script.
+
+
+.. seealso::
+
+ :pep:`278` - Universal Newline Support
+ Written and implemented by Jack Jansen.
+
+.. % ======================================================================
+
+
+.. _section-enumerate:
+
+PEP 279: enumerate()
+====================
+
+A new built-in function, :func:`enumerate`, will make certain loops a bit
+clearer. ``enumerate(thing)``, where *thing* is either an iterator or a
+sequence, returns a iterator that will return ``(0, thing[0])``, ``(1,
+thing[1])``, ``(2, thing[2])``, and so forth.
+
+A common idiom to change every element of a list looks like this::
+
+ for i in range(len(L)):
+ item = L[i]
+ # ... compute some result based on item ...
+ L[i] = result
+
+This can be rewritten using :func:`enumerate` as::
+
+ for i, item in enumerate(L):
+ # ... compute some result based on item ...
+ L[i] = result
+
+
+.. seealso::
+
+ :pep:`279` - The enumerate() built-in function
+ Written and implemented by Raymond D. Hettinger.
+
+.. % ======================================================================
+
+
+PEP 282: The logging Package
+============================
+
+A standard package for writing logs, :mod:`logging`, has been added to Python
+2.3. It provides a powerful and flexible mechanism for generating logging
+output which can then be filtered and processed in various ways. A
+configuration file written in a standard format can be used to control the
+logging behavior of a program. Python includes handlers that will write log
+records to standard error or to a file or socket, send them to the system log,
+or even e-mail them to a particular address; of course, it's also possible to
+write your own handler classes.
+
+The :class:`Logger` class is the primary class. Most application code will deal
+with one or more :class:`Logger` objects, each one used by a particular
+subsystem of the application. Each :class:`Logger` is identified by a name, and
+names are organized into a hierarchy using ``.`` as the component separator.
+For example, you might have :class:`Logger` instances named ``server``,
+``server.auth`` and ``server.network``. The latter two instances are below
+``server`` in the hierarchy. This means that if you turn up the verbosity for
+``server`` or direct ``server`` messages to a different handler, the changes
+will also apply to records logged to ``server.auth`` and ``server.network``.
+There's also a root :class:`Logger` that's the parent of all other loggers.
+
+For simple uses, the :mod:`logging` package contains some convenience functions
+that always use the root log::
+
+ import logging
+
+ logging.debug('Debugging information')
+ logging.info('Informational message')
+ logging.warning('Warning:config file %s not found', 'server.conf')
+ logging.error('Error occurred')
+ logging.critical('Critical error -- shutting down')
+
+This produces the following output::
+
+ WARNING:root:Warning:config file server.conf not found
+ ERROR:root:Error occurred
+ CRITICAL:root:Critical error -- shutting down
+
+In the default configuration, informational and debugging messages are
+suppressed and the output is sent to standard error. You can enable the display
+of informational and debugging messages by calling the :meth:`setLevel` method
+on the root logger.
+
+Notice the :func:`warning` call's use of string formatting operators; all of the
+functions for logging messages take the arguments ``(msg, arg1, arg2, ...)`` and
+log the string resulting from ``msg % (arg1, arg2, ...)``.
+
+There's also an :func:`exception` function that records the most recent
+traceback. Any of the other functions will also record the traceback if you
+specify a true value for the keyword argument *exc_info*. ::
+
+ def f():
+ try: 1/0
+ except: logging.exception('Problem recorded')
+
+ f()
+
+This produces the following output::
+
+ ERROR:root:Problem recorded
+ Traceback (most recent call last):
+ File "t.py", line 6, in f
+ 1/0
+ ZeroDivisionError: integer division or modulo by zero
+
+Slightly more advanced programs will use a logger other than the root logger.
+The :func:`getLogger(name)` function is used to get a particular log, creating
+it if it doesn't exist yet. :func:`getLogger(None)` returns the root logger. ::
+
+ log = logging.getLogger('server')
+ ...
+ log.info('Listening on port %i', port)
+ ...
+ log.critical('Disk full')
+ ...
+
+Log records are usually propagated up the hierarchy, so a message logged to
+``server.auth`` is also seen by ``server`` and ``root``, but a :class:`Logger`
+can prevent this by setting its :attr:`propagate` attribute to :const:`False`.
+
+There are more classes provided by the :mod:`logging` package that can be
+customized. When a :class:`Logger` instance is told to log a message, it
+creates a :class:`LogRecord` instance that is sent to any number of different
+:class:`Handler` instances. Loggers and handlers can also have an attached list
+of filters, and each filter can cause the :class:`LogRecord` to be ignored or
+can modify the record before passing it along. When they're finally output,
+:class:`LogRecord` instances are converted to text by a :class:`Formatter`
+class. All of these classes can be replaced by your own specially-written
+classes.
+
+With all of these features the :mod:`logging` package should provide enough
+flexibility for even the most complicated applications. This is only an
+incomplete overview of its features, so please see the package's reference
+documentation for all of the details. Reading :pep:`282` will also be helpful.
+
+
+.. seealso::
+
+ :pep:`282` - A Logging System
+ Written by Vinay Sajip and Trent Mick; implemented by Vinay Sajip.
+
+.. % ======================================================================
+
+
+.. _section-bool:
+
+PEP 285: A Boolean Type
+=======================
+
+A Boolean type was added to Python 2.3. Two new constants were added to the
+:mod:`__builtin__` module, :const:`True` and :const:`False`. (:const:`True` and
+:const:`False` constants were added to the built-ins in Python 2.2.1, but the
+2.2.1 versions are simply set to integer values of 1 and 0 and aren't a
+different type.)
+
+The type object for this new type is named :class:`bool`; the constructor for it
+takes any Python value and converts it to :const:`True` or :const:`False`. ::
+
+ >>> bool(1)
+ True
+ >>> bool(0)
+ False
+ >>> bool([])
+ False
+ >>> bool( (1,) )
+ True
+
+Most of the standard library modules and built-in functions have been changed to
+return Booleans. ::
+
+ >>> obj = []
+ >>> hasattr(obj, 'append')
+ True
+ >>> isinstance(obj, list)
+ True
+ >>> isinstance(obj, tuple)
+ False
+
+Python's Booleans were added with the primary goal of making code clearer. For
+example, if you're reading a function and encounter the statement ``return 1``,
+you might wonder whether the ``1`` represents a Boolean truth value, an index,
+or a coefficient that multiplies some other quantity. If the statement is
+``return True``, however, the meaning of the return value is quite clear.
+
+Python's Booleans were *not* added for the sake of strict type-checking. A very
+strict language such as Pascal would also prevent you performing arithmetic with
+Booleans, and would require that the expression in an :keyword:`if` statement
+always evaluate to a Boolean result. Python is not this strict and never will
+be, as :pep:`285` explicitly says. This means you can still use any expression
+in an :keyword:`if` statement, even ones that evaluate to a list or tuple or
+some random object. The Boolean type is a subclass of the :class:`int` class so
+that arithmetic using a Boolean still works. ::
+
+ >>> True + 1
+ 2
+ >>> False + 1
+ 1
+ >>> False * 75
+ 0
+ >>> True * 75
+ 75
+
+To sum up :const:`True` and :const:`False` in a sentence: they're alternative
+ways to spell the integer values 1 and 0, with the single difference that
+:func:`str` and :func:`repr` return the strings ``'True'`` and ``'False'``
+instead of ``'1'`` and ``'0'``.
+
+
+.. seealso::
+
+ :pep:`285` - Adding a bool type
+ Written and implemented by GvR.
+
+.. % ======================================================================
+
+
+PEP 293: Codec Error Handling Callbacks
+=======================================
+
+When encoding a Unicode string into a byte string, unencodable characters may be
+encountered. So far, Python has allowed specifying the error processing as
+either "strict" (raising :exc:`UnicodeError`), "ignore" (skipping the
+character), or "replace" (using a question mark in the output string), with
+"strict" being the default behavior. It may be desirable to specify alternative
+processing of such errors, such as inserting an XML character reference or HTML
+entity reference into the converted string.
+
+Python now has a flexible framework to add different processing strategies. New
+error handlers can be added with :func:`codecs.register_error`, and codecs then
+can access the error handler with :func:`codecs.lookup_error`. An equivalent C
+API has been added for codecs written in C. The error handler gets the necessary
+state information such as the string being converted, the position in the string
+where the error was detected, and the target encoding. The handler can then
+either raise an exception or return a replacement string.
+
+Two additional error handlers have been implemented using this framework:
+"backslashreplace" uses Python backslash quoting to represent unencodable
+characters and "xmlcharrefreplace" emits XML character references.
+
+
+.. seealso::
+
+ :pep:`293` - Codec Error Handling Callbacks
+ Written and implemented by Walter Dörwald.
+
+.. % ======================================================================
+
+
+.. _section-pep301:
+
+PEP 301: Package Index and Metadata for Distutils
+=================================================
+
+Support for the long-requested Python catalog makes its first appearance in 2.3.
+
+The heart of the catalog is the new Distutils :command:`register` command.
+Running ``python setup.py register`` will collect the metadata describing a
+package, such as its name, version, maintainer, description, &c., and send it to
+a central catalog server. The resulting catalog is available from
+http://www.python.org/pypi.
+
+To make the catalog a bit more useful, a new optional *classifiers* keyword
+argument has been added to the Distutils :func:`setup` function. A list of
+`Trove <http://catb.org/~esr/trove/>`_-style strings can be supplied to help
+classify the software.
+
+Here's an example :file:`setup.py` with classifiers, written to be compatible
+with older versions of the Distutils::
+
+ from distutils import core
+ kw = {'name': "Quixote",
+ 'version': "0.5.1",
+ 'description': "A highly Pythonic Web application framework",
+ # ...
+ }
+
+ if (hasattr(core, 'setup_keywords') and
+ 'classifiers' in core.setup_keywords):
+ kw['classifiers'] = \
+ ['Topic :: Internet :: WWW/HTTP :: Dynamic Content',
+ 'Environment :: No Input/Output (Daemon)',
+ 'Intended Audience :: Developers'],
+
+ core.setup(**kw)
+
+The full list of classifiers can be obtained by running ``python setup.py
+register --list-classifiers``.
+
+
+.. seealso::
+
+ :pep:`301` - Package Index and Metadata for Distutils
+ Written and implemented by Richard Jones.
+
+.. % ======================================================================
+
+
+.. _section-pep302:
+
+PEP 302: New Import Hooks
+=========================
+
+While it's been possible to write custom import hooks ever since the
+:mod:`ihooks` module was introduced in Python 1.3, no one has ever been really
+happy with it because writing new import hooks is difficult and messy. There
+have been various proposed alternatives such as the :mod:`imputil` and :mod:`iu`
+modules, but none of them has ever gained much acceptance, and none of them were
+easily usable from C code.
+
+:pep:`302` borrows ideas from its predecessors, especially from Gordon
+McMillan's :mod:`iu` module. Three new items are added to the :mod:`sys`
+module:
+
+* ``sys.path_hooks`` is a list of callable objects; most often they'll be
+ classes. Each callable takes a string containing a path and either returns an
+ importer object that will handle imports from this path or raises an
+ :exc:`ImportError` exception if it can't handle this path.
+
+* ``sys.path_importer_cache`` caches importer objects for each path, so
+ ``sys.path_hooks`` will only need to be traversed once for each path.
+
+* ``sys.meta_path`` is a list of importer objects that will be traversed before
+ ``sys.path`` is checked. This list is initially empty, but user code can add
+ objects to it. Additional built-in and frozen modules can be imported by an
+ object added to this list.
+
+Importer objects must have a single method, :meth:`find_module(fullname,
+path=None)`. *fullname* will be a module or package name, e.g. ``string`` or
+``distutils.core``. :meth:`find_module` must return a loader object that has a
+single method, :meth:`load_module(fullname)`, that creates and returns the
+corresponding module object.
+
+Pseudo-code for Python's new import logic, therefore, looks something like this
+(simplified a bit; see :pep:`302` for the full details)::
+
+ for mp in sys.meta_path:
+ loader = mp(fullname)
+ if loader is not None:
+ <module> = loader.load_module(fullname)
+
+ for path in sys.path:
+ for hook in sys.path_hooks:
+ try:
+ importer = hook(path)
+ except ImportError:
+ # ImportError, so try the other path hooks
+ pass
+ else:
+ loader = importer.find_module(fullname)
+ <module> = loader.load_module(fullname)
+
+ # Not found!
+ raise ImportError
+
+
+.. seealso::
+
+ :pep:`302` - New Import Hooks
+ Written by Just van Rossum and Paul Moore. Implemented by Just van Rossum.
+
+.. % ======================================================================
+
+
+.. _section-pep305:
+
+PEP 305: Comma-separated Files
+==============================
+
+Comma-separated files are a format frequently used for exporting data from
+databases and spreadsheets. Python 2.3 adds a parser for comma-separated files.
+
+Comma-separated format is deceptively simple at first glance::
+
+ Costs,150,200,3.95
+
+Read a line and call ``line.split(',')``: what could be simpler? But toss in
+string data that can contain commas, and things get more complicated::
+
+ "Costs",150,200,3.95,"Includes taxes, shipping, and sundry items"
+
+A big ugly regular expression can parse this, but using the new :mod:`csv`
+package is much simpler::
+
+ import csv
+
+ input = open('datafile', 'rb')
+ reader = csv.reader(input)
+ for line in reader:
+ print line
+
+The :func:`reader` function takes a number of different options. The field
+separator isn't limited to the comma and can be changed to any character, and so
+can the quoting and line-ending characters.
+
+Different dialects of comma-separated files can be defined and registered;
+currently there are two dialects, both used by Microsoft Excel. A separate
+:class:`csv.writer` class will generate comma-separated files from a succession
+of tuples or lists, quoting strings that contain the delimiter.
+
+
+.. seealso::
+
+ :pep:`305` - CSV File API
+ Written and implemented by Kevin Altis, Dave Cole, Andrew McNamara, Skip
+ Montanaro, Cliff Wells.
+
+.. % ======================================================================
+
+
+.. _section-pep307:
+
+PEP 307: Pickle Enhancements
+============================
+
+The :mod:`pickle` and :mod:`cPickle` modules received some attention during the
+2.3 development cycle. In 2.2, new-style classes could be pickled without
+difficulty, but they weren't pickled very compactly; :pep:`307` quotes a trivial
+example where a new-style class results in a pickled string three times longer
+than that for a classic class.
+
+The solution was to invent a new pickle protocol. The :func:`pickle.dumps`
+function has supported a text-or-binary flag for a long time. In 2.3, this
+flag is redefined from a Boolean to an integer: 0 is the old text-mode pickle
+format, 1 is the old binary format, and now 2 is a new 2.3-specific format. A
+new constant, :const:`pickle.HIGHEST_PROTOCOL`, can be used to select the
+fanciest protocol available.
+
+Unpickling is no longer considered a safe operation. 2.2's :mod:`pickle`
+provided hooks for trying to prevent unsafe classes from being unpickled
+(specifically, a :attr:`__safe_for_unpickling__` attribute), but none of this
+code was ever audited and therefore it's all been ripped out in 2.3. You should
+not unpickle untrusted data in any version of Python.
+
+To reduce the pickling overhead for new-style classes, a new interface for
+customizing pickling was added using three special methods:
+:meth:`__getstate__`, :meth:`__setstate__`, and :meth:`__getnewargs__`. Consult
+:pep:`307` for the full semantics of these methods.
+
+As a way to compress pickles yet further, it's now possible to use integer codes
+instead of long strings to identify pickled classes. The Python Software
+Foundation will maintain a list of standardized codes; there's also a range of
+codes for private use. Currently no codes have been specified.
+
+
+.. seealso::
+
+ :pep:`307` - Extensions to the pickle protocol
+ Written and implemented by Guido van Rossum and Tim Peters.
+
+.. % ======================================================================
+
+
+.. _section-slices:
+
+Extended Slices
+===============
+
+Ever since Python 1.4, the slicing syntax has supported an optional third "step"
+or "stride" argument. For example, these are all legal Python syntax:
+``L[1:10:2]``, ``L[:-1:1]``, ``L[::-1]``. This was added to Python at the
+request of the developers of Numerical Python, which uses the third argument
+extensively. However, Python's built-in list, tuple, and string sequence types
+have never supported this feature, raising a :exc:`TypeError` if you tried it.
+Michael Hudson contributed a patch to fix this shortcoming.
+
+For example, you can now easily extract the elements of a list that have even
+indexes::
+
+ >>> L = range(10)
+ >>> L[::2]
+ [0, 2, 4, 6, 8]
+
+Negative values also work to make a copy of the same list in reverse order::
+
+ >>> L[::-1]
+ [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
+
+This also works for tuples, arrays, and strings::
+
+ >>> s='abcd'
+ >>> s[::2]
+ 'ac'
+ >>> s[::-1]
+ 'dcba'
+
+If you have a mutable sequence such as a list or an array you can assign to or
+delete an extended slice, but there are some differences between assignment to
+extended and regular slices. Assignment to a regular slice can be used to
+change the length of the sequence::
+
+ >>> a = range(3)
+ >>> a
+ [0, 1, 2]
+ >>> a[1:3] = [4, 5, 6]
+ >>> a
+ [0, 4, 5, 6]
+
+Extended slices aren't this flexible. When assigning to an extended slice, the
+list on the right hand side of the statement must contain the same number of
+items as the slice it is replacing::
+
+ >>> a = range(4)
+ >>> a
+ [0, 1, 2, 3]
+ >>> a[::2]
+ [0, 2]
+ >>> a[::2] = [0, -1]
+ >>> a
+ [0, 1, -1, 3]
+ >>> a[::2] = [0,1,2]
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ ValueError: attempt to assign sequence of size 3 to extended slice of size 2
+
+Deletion is more straightforward::
+
+ >>> a = range(4)
+ >>> a
+ [0, 1, 2, 3]
+ >>> a[::2]
+ [0, 2]
+ >>> del a[::2]
+ >>> a
+ [1, 3]
+
+One can also now pass slice objects to the :meth:`__getitem__` methods of the
+built-in sequences::
+
+ >>> range(10).__getitem__(slice(0, 5, 2))
+ [0, 2, 4]
+
+Or use slice objects directly in subscripts::
+
+ >>> range(10)[slice(0, 5, 2)]
+ [0, 2, 4]
+
+To simplify implementing sequences that support extended slicing, slice objects
+now have a method :meth:`indices(length)` which, given the length of a sequence,
+returns a ``(start, stop, step)`` tuple that can be passed directly to
+:func:`range`. :meth:`indices` handles omitted and out-of-bounds indices in a
+manner consistent with regular slices (and this innocuous phrase hides a welter
+of confusing details!). The method is intended to be used like this::
+
+ class FakeSeq:
+ ...
+ def calc_item(self, i):
+ ...
+ def __getitem__(self, item):
+ if isinstance(item, slice):
+ indices = item.indices(len(self))
+ return FakeSeq([self.calc_item(i) for i in range(*indices)])
+ else:
+ return self.calc_item(i)
+
+From this example you can also see that the built-in :class:`slice` object is
+now the type object for the slice type, and is no longer a function. This is
+consistent with Python 2.2, where :class:`int`, :class:`str`, etc., underwent
+the same change.
+
+.. % ======================================================================
+
+
+Other Language Changes
+======================
+
+Here are all of the changes that Python 2.3 makes to the core Python language.
+
+* The :keyword:`yield` statement is now always a keyword, as described in
+ section :ref:`section-generators` of this document.
+
+* A new built-in function :func:`enumerate` was added, as described in section
+ :ref:`section-enumerate` of this document.
+
+* Two new constants, :const:`True` and :const:`False` were added along with the
+ built-in :class:`bool` type, as described in section :ref:`section-bool` of this
+ document.
+
+* The :func:`int` type constructor will now return a long integer instead of
+ raising an :exc:`OverflowError` when a string or floating-point number is too
+ large to fit into an integer. This can lead to the paradoxical result that
+ ``isinstance(int(expression), int)`` is false, but that seems unlikely to cause
+ problems in practice.
+
+* Built-in types now support the extended slicing syntax, as described in
+ section :ref:`section-slices` of this document.
+
+* A new built-in function, :func:`sum(iterable, start=0)`, adds up the numeric
+ items in the iterable object and returns their sum. :func:`sum` only accepts
+ numbers, meaning that you can't use it to concatenate a bunch of strings.
+ (Contributed by Alex Martelli.)
+
+* ``list.insert(pos, value)`` used to insert *value* at the front of the list
+ when *pos* was negative. The behaviour has now been changed to be consistent
+ with slice indexing, so when *pos* is -1 the value will be inserted before the
+ last element, and so forth.
+
+* ``list.index(value)``, which searches for *value* within the list and returns
+ its index, now takes optional *start* and *stop* arguments to limit the search
+ to only part of the list.
+
+* Dictionaries have a new method, :meth:`pop(key[, *default*])`, that returns
+ the value corresponding to *key* and removes that key/value pair from the
+ dictionary. If the requested key isn't present in the dictionary, *default* is
+ returned if it's specified and :exc:`KeyError` raised if it isn't. ::
+
+ >>> d = {1:2}
+ >>> d
+ {1: 2}
+ >>> d.pop(4)
+ Traceback (most recent call last):
+ File "stdin", line 1, in ?
+ KeyError: 4
+ >>> d.pop(1)
+ 2
+ >>> d.pop(1)
+ Traceback (most recent call last):
+ File "stdin", line 1, in ?
+ KeyError: 'pop(): dictionary is empty'
+ >>> d
+ {}
+ >>>
+
+ There's also a new class method, :meth:`dict.fromkeys(iterable, value)`, that
+ creates a dictionary with keys taken from the supplied iterator *iterable* and
+ all values set to *value*, defaulting to ``None``.
+
+ (Patches contributed by Raymond Hettinger.)
+
+ Also, the :func:`dict` constructor now accepts keyword arguments to simplify
+ creating small dictionaries::
+
+ >>> dict(red=1, blue=2, green=3, black=4)
+ {'blue': 2, 'black': 4, 'green': 3, 'red': 1}
+
+ (Contributed by Just van Rossum.)
+
+* The :keyword:`assert` statement no longer checks the ``__debug__`` flag, so
+ you can no longer disable assertions by assigning to ``__debug__``. Running
+ Python with the :option:`-O` switch will still generate code that doesn't
+ execute any assertions.
+
+* Most type objects are now callable, so you can use them to create new objects
+ such as functions, classes, and modules. (This means that the :mod:`new` module
+ can be deprecated in a future Python version, because you can now use the type
+ objects available in the :mod:`types` module.) For example, you can create a new
+ module object with the following code:
+
+ .. % XXX should new.py use PendingDeprecationWarning?
+
+ ::
+
+ >>> import types
+ >>> m = types.ModuleType('abc','docstring')
+ >>> m
+ <module 'abc' (built-in)>
+ >>> m.__doc__
+ 'docstring'
+
+* A new warning, :exc:`PendingDeprecationWarning` was added to indicate features
+ which are in the process of being deprecated. The warning will *not* be printed
+ by default. To check for use of features that will be deprecated in the future,
+ supply :option:`-Walways::PendingDeprecationWarning::` on the command line or
+ use :func:`warnings.filterwarnings`.
+
+* The process of deprecating string-based exceptions, as in ``raise "Error
+ occurred"``, has begun. Raising a string will now trigger
+ :exc:`PendingDeprecationWarning`.
+
+* Using ``None`` as a variable name will now result in a :exc:`SyntaxWarning`
+ warning. In a future version of Python, ``None`` may finally become a keyword.
+
+* The :meth:`xreadlines` method of file objects, introduced in Python 2.1, is no
+ longer necessary because files now behave as their own iterator.
+ :meth:`xreadlines` was originally introduced as a faster way to loop over all
+ the lines in a file, but now you can simply write ``for line in file_obj``.
+ File objects also have a new read-only :attr:`encoding` attribute that gives the
+ encoding used by the file; Unicode strings written to the file will be
+ automatically converted to bytes using the given encoding.
+
+* The method resolution order used by new-style classes has changed, though
+ you'll only notice the difference if you have a really complicated inheritance
+ hierarchy. Classic classes are unaffected by this change. Python 2.2
+ originally used a topological sort of a class's ancestors, but 2.3 now uses the
+ C3 algorithm as described in the paper `"A Monotonic Superclass Linearization
+ for Dylan" <http://www.webcom.com/haahr/dylan/linearization-oopsla96.html>`_. To
+ understand the motivation for this change, read Michele Simionato's article
+ `"Python 2.3 Method Resolution Order" <http://www.python.org/2.3/mro.html>`_, or
+ read the thread on python-dev starting with the message at
+ http://mail.python.org/pipermail/python-dev/2002-October/029035.html. Samuele
+ Pedroni first pointed out the problem and also implemented the fix by coding the
+ C3 algorithm.
+
+* Python runs multithreaded programs by switching between threads after
+ executing N bytecodes. The default value for N has been increased from 10 to
+ 100 bytecodes, speeding up single-threaded applications by reducing the
+ switching overhead. Some multithreaded applications may suffer slower response
+ time, but that's easily fixed by setting the limit back to a lower number using
+ :func:`sys.setcheckinterval(N)`. The limit can be retrieved with the new
+ :func:`sys.getcheckinterval` function.
+
+* One minor but far-reaching change is that the names of extension types defined
+ by the modules included with Python now contain the module and a ``'.'`` in
+ front of the type name. For example, in Python 2.2, if you created a socket and
+ printed its :attr:`__class__`, you'd get this output::
+
+ >>> s = socket.socket()
+ >>> s.__class__
+ <type 'socket'>
+
+ In 2.3, you get this::
+
+ >>> s.__class__
+ <type '_socket.socket'>
+
+* One of the noted incompatibilities between old- and new-style classes has been
+ removed: you can now assign to the :attr:`__name__` and :attr:`__bases__`
+ attributes of new-style classes. There are some restrictions on what can be
+ assigned to :attr:`__bases__` along the lines of those relating to assigning to
+ an instance's :attr:`__class__` attribute.
+
+.. % ======================================================================
+
+
+String Changes
+--------------
+
+* The :keyword:`in` operator now works differently for strings. Previously, when
+ evaluating ``X in Y`` where *X* and *Y* are strings, *X* could only be a single
+ character. That's now changed; *X* can be a string of any length, and ``X in Y``
+ will return :const:`True` if *X* is a substring of *Y*. If *X* is the empty
+ string, the result is always :const:`True`. ::
+
+ >>> 'ab' in 'abcd'
+ True
+ >>> 'ad' in 'abcd'
+ False
+ >>> '' in 'abcd'
+ True
+
+ Note that this doesn't tell you where the substring starts; if you need that
+ information, use the :meth:`find` string method.
+
+* The :meth:`strip`, :meth:`lstrip`, and :meth:`rstrip` string methods now have
+ an optional argument for specifying the characters to strip. The default is
+ still to remove all whitespace characters::
+
+ >>> ' abc '.strip()
+ 'abc'
+ >>> '><><abc<><><>'.strip('<>')
+ 'abc'
+ >>> '><><abc<><><>\n'.strip('<>')
+ 'abc<><><>\n'
+ >>> u'\u4000\u4001abc\u4000'.strip(u'\u4000')
+ u'\u4001abc'
+ >>>
+
+ (Suggested by Simon Brunning and implemented by Walter Dörwald.)
+
+* The :meth:`startswith` and :meth:`endswith` string methods now accept negative
+ numbers for the *start* and *end* parameters.
+
+* Another new string method is :meth:`zfill`, originally a function in the
+ :mod:`string` module. :meth:`zfill` pads a numeric string with zeros on the
+ left until it's the specified width. Note that the ``%`` operator is still more
+ flexible and powerful than :meth:`zfill`. ::
+
+ >>> '45'.zfill(4)
+ '0045'
+ >>> '12345'.zfill(4)
+ '12345'
+ >>> 'goofy'.zfill(6)
+ '0goofy'
+
+ (Contributed by Walter Dörwald.)
+
+* A new type object, :class:`basestring`, has been added. Both 8-bit strings and
+ Unicode strings inherit from this type, so ``isinstance(obj, basestring)`` will
+ return :const:`True` for either kind of string. It's a completely abstract
+ type, so you can't create :class:`basestring` instances.
+
+* Interned strings are no longer immortal and will now be garbage-collected in
+ the usual way when the only reference to them is from the internal dictionary of
+ interned strings. (Implemented by Oren Tirosh.)
+
+.. % ======================================================================
+
+
+Optimizations
+-------------
+
+* The creation of new-style class instances has been made much faster; they're
+ now faster than classic classes!
+
+* The :meth:`sort` method of list objects has been extensively rewritten by Tim
+ Peters, and the implementation is significantly faster.
+
+* Multiplication of large long integers is now much faster thanks to an
+ implementation of Karatsuba multiplication, an algorithm that scales better than
+ the O(n\*n) required for the grade-school multiplication algorithm. (Original
+ patch by Christopher A. Craig, and significantly reworked by Tim Peters.)
+
+* The ``SET_LINENO`` opcode is now gone. This may provide a small speed
+ increase, depending on your compiler's idiosyncrasies. See section
+ :ref:`section-other` for a longer explanation. (Removed by Michael Hudson.)
+
+* :func:`xrange` objects now have their own iterator, making ``for i in
+ xrange(n)`` slightly faster than ``for i in range(n)``. (Patch by Raymond
+ Hettinger.)
+
+* A number of small rearrangements have been made in various hotspots to improve
+ performance, such as inlining a function or removing some code. (Implemented
+ mostly by GvR, but lots of people have contributed single changes.)
+
+The net result of the 2.3 optimizations is that Python 2.3 runs the pystone
+benchmark around 25% faster than Python 2.2.
+
+.. % ======================================================================
+
+
+New, Improved, and Deprecated Modules
+=====================================
+
+As usual, Python's standard library received a number of enhancements and bug
+fixes. Here's a partial list of the most notable changes, sorted alphabetically
+by module name. Consult the :file:`Misc/NEWS` file in the source tree for a more
+complete list of changes, or look through the CVS logs for all the details.
+
+* The :mod:`array` module now supports arrays of Unicode characters using the
+ ``'u'`` format character. Arrays also now support using the ``+=`` assignment
+ operator to add another array's contents, and the ``*=`` assignment operator to
+ repeat an array. (Contributed by Jason Orendorff.)
+
+* The :mod:`bsddb` module has been replaced by version 4.1.6 of the `PyBSDDB
+ <http://pybsddb.sourceforge.net>`_ package, providing a more complete interface
+ to the transactional features of the BerkeleyDB library.
+
+ The old version of the module has been renamed to :mod:`bsddb185` and is no
+ longer built automatically; you'll have to edit :file:`Modules/Setup` to enable
+ it. Note that the new :mod:`bsddb` package is intended to be compatible with
+ the old module, so be sure to file bugs if you discover any incompatibilities.
+ When upgrading to Python 2.3, if the new interpreter is compiled with a new
+ version of the underlying BerkeleyDB library, you will almost certainly have to
+ convert your database files to the new version. You can do this fairly easily
+ with the new scripts :file:`db2pickle.py` and :file:`pickle2db.py` which you
+ will find in the distribution's :file:`Tools/scripts` directory. If you've
+ already been using the PyBSDDB package and importing it as :mod:`bsddb3`, you
+ will have to change your ``import`` statements to import it as :mod:`bsddb`.
+
+* The new :mod:`bz2` module is an interface to the bz2 data compression library.
+ bz2-compressed data is usually smaller than corresponding :mod:`zlib`\
+ -compressed data. (Contributed by Gustavo Niemeyer.)
+
+* A set of standard date/time types has been added in the new :mod:`datetime`
+ module. See the following section for more details.
+
+* The Distutils :class:`Extension` class now supports an extra constructor
+ argument named *depends* for listing additional source files that an extension
+ depends on. This lets Distutils recompile the module if any of the dependency
+ files are modified. For example, if :file:`sampmodule.c` includes the header
+ file :file:`sample.h`, you would create the :class:`Extension` object like
+ this::
+
+ ext = Extension("samp",
+ sources=["sampmodule.c"],
+ depends=["sample.h"])
+
+ Modifying :file:`sample.h` would then cause the module to be recompiled.
+ (Contributed by Jeremy Hylton.)
+
+* Other minor changes to Distutils: it now checks for the :envvar:`CC`,
+ :envvar:`CFLAGS`, :envvar:`CPP`, :envvar:`LDFLAGS`, and :envvar:`CPPFLAGS`
+ environment variables, using them to override the settings in Python's
+ configuration (contributed by Robert Weber).
+
+* Previously the :mod:`doctest` module would only search the docstrings of
+ public methods and functions for test cases, but it now also examines private
+ ones as well. The :func:`DocTestSuite(` function creates a
+ :class:`unittest.TestSuite` object from a set of :mod:`doctest` tests.
+
+* The new :func:`gc.get_referents(object)` function returns a list of all the
+ objects referenced by *object*.
+
+* The :mod:`getopt` module gained a new function, :func:`gnu_getopt`, that
+ supports the same arguments as the existing :func:`getopt` function but uses
+ GNU-style scanning mode. The existing :func:`getopt` stops processing options as
+ soon as a non-option argument is encountered, but in GNU-style mode processing
+ continues, meaning that options and arguments can be mixed. For example::
+
+ >>> getopt.getopt(['-f', 'filename', 'output', '-v'], 'f:v')
+ ([('-f', 'filename')], ['output', '-v'])
+ >>> getopt.gnu_getopt(['-f', 'filename', 'output', '-v'], 'f:v')
+ ([('-f', 'filename'), ('-v', '')], ['output'])
+
+ (Contributed by Peter Åstrand.)
+
+* The :mod:`grp`, :mod:`pwd`, and :mod:`resource` modules now return enhanced
+ tuples::
+
+ >>> import grp
+ >>> g = grp.getgrnam('amk')
+ >>> g.gr_name, g.gr_gid
+ ('amk', 500)
+
+* The :mod:`gzip` module can now handle files exceeding 2 GiB.
+
+* The new :mod:`heapq` module contains an implementation of a heap queue
+ algorithm. A heap is an array-like data structure that keeps items in a
+ partially sorted order such that, for every index *k*, ``heap[k] <=
+ heap[2*k+1]`` and ``heap[k] <= heap[2*k+2]``. This makes it quick to remove the
+ smallest item, and inserting a new item while maintaining the heap property is
+ O(lg n). (See http://www.nist.gov/dads/HTML/priorityque.html for more
+ information about the priority queue data structure.)
+
+ The :mod:`heapq` module provides :func:`heappush` and :func:`heappop` functions
+ for adding and removing items while maintaining the heap property on top of some
+ other mutable Python sequence type. Here's an example that uses a Python list::
+
+ >>> import heapq
+ >>> heap = []
+ >>> for item in [3, 7, 5, 11, 1]:
+ ... heapq.heappush(heap, item)
+ ...
+ >>> heap
+ [1, 3, 5, 11, 7]
+ >>> heapq.heappop(heap)
+ 1
+ >>> heapq.heappop(heap)
+ 3
+ >>> heap
+ [5, 7, 11]
+
+ (Contributed by Kevin O'Connor.)
+
+* The IDLE integrated development environment has been updated using the code
+ from the IDLEfork project (http://idlefork.sf.net). The most notable feature is
+ that the code being developed is now executed in a subprocess, meaning that
+ there's no longer any need for manual ``reload()`` operations. IDLE's core code
+ has been incorporated into the standard library as the :mod:`idlelib` package.
+
+* The :mod:`imaplib` module now supports IMAP over SSL. (Contributed by Piers
+ Lauder and Tino Lange.)
+
+* The :mod:`itertools` contains a number of useful functions for use with
+ iterators, inspired by various functions provided by the ML and Haskell
+ languages. For example, ``itertools.ifilter(predicate, iterator)`` returns all
+ elements in the iterator for which the function :func:`predicate` returns
+ :const:`True`, and ``itertools.repeat(obj, N)`` returns ``obj`` *N* times.
+ There are a number of other functions in the module; see the package's reference
+ documentation for details.
+ (Contributed by Raymond Hettinger.)
+
+* Two new functions in the :mod:`math` module, :func:`degrees(rads)` and
+ :func:`radians(degs)`, convert between radians and degrees. Other functions in
+ the :mod:`math` module such as :func:`math.sin` and :func:`math.cos` have always
+ required input values measured in radians. Also, an optional *base* argument
+ was added to :func:`math.log` to make it easier to compute logarithms for bases
+ other than ``e`` and ``10``. (Contributed by Raymond Hettinger.)
+
+* Several new POSIX functions (:func:`getpgid`, :func:`killpg`, :func:`lchown`,
+ :func:`loadavg`, :func:`major`, :func:`makedev`, :func:`minor`, and
+ :func:`mknod`) were added to the :mod:`posix` module that underlies the
+ :mod:`os` module. (Contributed by Gustavo Niemeyer, Geert Jansen, and Denis S.
+ Otkidach.)
+
+* In the :mod:`os` module, the :func:`\*stat` family of functions can now report
+ fractions of a second in a timestamp. Such time stamps are represented as
+ floats, similar to the value returned by :func:`time.time`.
+
+ During testing, it was found that some applications will break if time stamps
+ are floats. For compatibility, when using the tuple interface of the
+ :class:`stat_result` time stamps will be represented as integers. When using
+ named fields (a feature first introduced in Python 2.2), time stamps are still
+ represented as integers, unless :func:`os.stat_float_times` is invoked to enable
+ float return values::
+
+ >>> os.stat("/tmp").st_mtime
+ 1034791200
+ >>> os.stat_float_times(True)
+ >>> os.stat("/tmp").st_mtime
+ 1034791200.6335014
+
+ In Python 2.4, the default will change to always returning floats.
+
+ Application developers should enable this feature only if all their libraries
+ work properly when confronted with floating point time stamps, or if they use
+ the tuple API. If used, the feature should be activated on an application level
+ instead of trying to enable it on a per-use basis.
+
+* The :mod:`optparse` module contains a new parser for command-line arguments
+ that can convert option values to a particular Python type and will
+ automatically generate a usage message. See the following section for more
+ details.
+
+* The old and never-documented :mod:`linuxaudiodev` module has been deprecated,
+ and a new version named :mod:`ossaudiodev` has been added. The module was
+ renamed because the OSS sound drivers can be used on platforms other than Linux,
+ and the interface has also been tidied and brought up to date in various ways.
+ (Contributed by Greg Ward and Nicholas FitzRoy-Dale.)
+
+* The new :mod:`platform` module contains a number of functions that try to
+ determine various properties of the platform you're running on. There are
+ functions for getting the architecture, CPU type, the Windows OS version, and
+ even the Linux distribution version. (Contributed by Marc-André Lemburg.)
+
+* The parser objects provided by the :mod:`pyexpat` module can now optionally
+ buffer character data, resulting in fewer calls to your character data handler
+ and therefore faster performance. Setting the parser object's
+ :attr:`buffer_text` attribute to :const:`True` will enable buffering.
+
+* The :func:`sample(population, k)` function was added to the :mod:`random`
+ module. *population* is a sequence or :class:`xrange` object containing the
+ elements of a population, and :func:`sample` chooses *k* elements from the
+ population without replacing chosen elements. *k* can be any value up to
+ ``len(population)``. For example::
+
+ >>> days = ['Mo', 'Tu', 'We', 'Th', 'Fr', 'St', 'Sn']
+ >>> random.sample(days, 3) # Choose 3 elements
+ ['St', 'Sn', 'Th']
+ >>> random.sample(days, 7) # Choose 7 elements
+ ['Tu', 'Th', 'Mo', 'We', 'St', 'Fr', 'Sn']
+ >>> random.sample(days, 7) # Choose 7 again
+ ['We', 'Mo', 'Sn', 'Fr', 'Tu', 'St', 'Th']
+ >>> random.sample(days, 8) # Can't choose eight
+ Traceback (most recent call last):
+ File "<stdin>", line 1, in ?
+ File "random.py", line 414, in sample
+ raise ValueError, "sample larger than population"
+ ValueError: sample larger than population
+ >>> random.sample(xrange(1,10000,2), 10) # Choose ten odd nos. under 10000
+ [3407, 3805, 1505, 7023, 2401, 2267, 9733, 3151, 8083, 9195]
+
+ The :mod:`random` module now uses a new algorithm, the Mersenne Twister,
+ implemented in C. It's faster and more extensively studied than the previous
+ algorithm.
+
+ (All changes contributed by Raymond Hettinger.)
+
+* The :mod:`readline` module also gained a number of new functions:
+ :func:`get_history_item`, :func:`get_current_history_length`, and
+ :func:`redisplay`.
+
+* The :mod:`rexec` and :mod:`Bastion` modules have been declared dead, and
+ attempts to import them will fail with a :exc:`RuntimeError`. New-style classes
+ provide new ways to break out of the restricted execution environment provided
+ by :mod:`rexec`, and no one has interest in fixing them or time to do so. If
+ you have applications using :mod:`rexec`, rewrite them to use something else.
+
+ (Sticking with Python 2.2 or 2.1 will not make your applications any safer
+ because there are known bugs in the :mod:`rexec` module in those versions. To
+ repeat: if you're using :mod:`rexec`, stop using it immediately.)
+
+* The :mod:`rotor` module has been deprecated because the algorithm it uses for
+ encryption is not believed to be secure. If you need encryption, use one of the
+ several AES Python modules that are available separately.
+
+* The :mod:`shutil` module gained a :func:`move(src, dest)` function that
+ recursively moves a file or directory to a new location.
+
+* Support for more advanced POSIX signal handling was added to the :mod:`signal`
+ but then removed again as it proved impossible to make it work reliably across
+ platforms.
+
+* The :mod:`socket` module now supports timeouts. You can call the
+ :meth:`settimeout(t)` method on a socket object to set a timeout of *t* seconds.
+ Subsequent socket operations that take longer than *t* seconds to complete will
+ abort and raise a :exc:`socket.timeout` exception.
+
+ The original timeout implementation was by Tim O'Malley. Michael Gilfix
+ integrated it into the Python :mod:`socket` module and shepherded it through a
+ lengthy review. After the code was checked in, Guido van Rossum rewrote parts
+ of it. (This is a good example of a collaborative development process in
+ action.)
+
+* On Windows, the :mod:`socket` module now ships with Secure Sockets Layer
+ (SSL) support.
+
+* The value of the C :const:`PYTHON_API_VERSION` macro is now exposed at the
+ Python level as ``sys.api_version``. The current exception can be cleared by
+ calling the new :func:`sys.exc_clear` function.
+
+* The new :mod:`tarfile` module allows reading from and writing to
+ :program:`tar`\ -format archive files. (Contributed by Lars Gustäbel.)
+
+* The new :mod:`textwrap` module contains functions for wrapping strings
+ containing paragraphs of text. The :func:`wrap(text, width)` function takes a
+ string and returns a list containing the text split into lines of no more than
+ the chosen width. The :func:`fill(text, width)` function returns a single
+ string, reformatted to fit into lines no longer than the chosen width. (As you
+ can guess, :func:`fill` is built on top of :func:`wrap`. For example::
+
+ >>> import textwrap
+ >>> paragraph = "Not a whit, we defy augury: ... more text ..."
+ >>> textwrap.wrap(paragraph, 60)
+ ["Not a whit, we defy augury: there's a special providence in",
+ "the fall of a sparrow. If it be now, 'tis not to come; if it",
+ ...]
+ >>> print textwrap.fill(paragraph, 35)
+ Not a whit, we defy augury: there's
+ a special providence in the fall of
+ a sparrow. If it be now, 'tis not
+ to come; if it be not to come, it
+ will be now; if it be not now, yet
+ it will come: the readiness is all.
+ >>>
+
+ The module also contains a :class:`TextWrapper` class that actually implements
+ the text wrapping strategy. Both the :class:`TextWrapper` class and the
+ :func:`wrap` and :func:`fill` functions support a number of additional keyword
+ arguments for fine-tuning the formatting; consult the module's documentation
+ for details. (Contributed by Greg Ward.)
+
+* The :mod:`thread` and :mod:`threading` modules now have companion modules,
+ :mod:`dummy_thread` and :mod:`dummy_threading`, that provide a do-nothing
+ implementation of the :mod:`thread` module's interface for platforms where
+ threads are not supported. The intention is to simplify thread-aware modules
+ (ones that *don't* rely on threads to run) by putting the following code at the
+ top::
+
+ try:
+ import threading as _threading
+ except ImportError:
+ import dummy_threading as _threading
+
+ In this example, :mod:`_threading` is used as the module name to make it clear
+ that the module being used is not necessarily the actual :mod:`threading`
+ module. Code can call functions and use classes in :mod:`_threading` whether or
+ not threads are supported, avoiding an :keyword:`if` statement and making the
+ code slightly clearer. This module will not magically make multithreaded code
+ run without threads; code that waits for another thread to return or to do
+ something will simply hang forever.
+
+* The :mod:`time` module's :func:`strptime` function has long been an annoyance
+ because it uses the platform C library's :func:`strptime` implementation, and
+ different platforms sometimes have odd bugs. Brett Cannon contributed a
+ portable implementation that's written in pure Python and should behave
+ identically on all platforms.
+
+* The new :mod:`timeit` module helps measure how long snippets of Python code
+ take to execute. The :file:`timeit.py` file can be run directly from the
+ command line, or the module's :class:`Timer` class can be imported and used
+ directly. Here's a short example that figures out whether it's faster to
+ convert an 8-bit string to Unicode by appending an empty Unicode string to it or
+ by using the :func:`unicode` function::
+
+ import timeit
+
+ timer1 = timeit.Timer('unicode("abc")')
+ timer2 = timeit.Timer('"abc" + u""')
+
+ # Run three trials
+ print timer1.repeat(repeat=3, number=100000)
+ print timer2.repeat(repeat=3, number=100000)
+
+ # On my laptop this outputs:
+ # [0.36831796169281006, 0.37441694736480713, 0.35304892063140869]
+ # [0.17574405670166016, 0.18193507194519043, 0.17565798759460449]
+
+* The :mod:`Tix` module has received various bug fixes and updates for the
+ current version of the Tix package.
+
+* The :mod:`Tkinter` module now works with a thread-enabled version of Tcl.
+ Tcl's threading model requires that widgets only be accessed from the thread in
+ which they're created; accesses from another thread can cause Tcl to panic. For
+ certain Tcl interfaces, :mod:`Tkinter` will now automatically avoid this when a
+ widget is accessed from a different thread by marshalling a command, passing it
+ to the correct thread, and waiting for the results. Other interfaces can't be
+ handled automatically but :mod:`Tkinter` will now raise an exception on such an
+ access so that you can at least find out about the problem. See
+ http://mail.python.org/pipermail/python-dev/2002-December/031107.html for a more
+ detailed explanation of this change. (Implemented by Martin von Löwis.)
+
+ .. %
+
+* Calling Tcl methods through :mod:`_tkinter` no longer returns only strings.
+ Instead, if Tcl returns other objects those objects are converted to their
+ Python equivalent, if one exists, or wrapped with a :class:`_tkinter.Tcl_Obj`
+ object if no Python equivalent exists. This behavior can be controlled through
+ the :meth:`wantobjects` method of :class:`tkapp` objects.
+
+ When using :mod:`_tkinter` through the :mod:`Tkinter` module (as most Tkinter
+ applications will), this feature is always activated. It should not cause
+ compatibility problems, since Tkinter would always convert string results to
+ Python types where possible.
+
+ If any incompatibilities are found, the old behavior can be restored by setting
+ the :attr:`wantobjects` variable in the :mod:`Tkinter` module to false before
+ creating the first :class:`tkapp` object. ::
+
+ import Tkinter
+ Tkinter.wantobjects = 0
+
+ Any breakage caused by this change should be reported as a bug.
+
+* The :mod:`UserDict` module has a new :class:`DictMixin` class which defines
+ all dictionary methods for classes that already have a minimum mapping
+ interface. This greatly simplifies writing classes that need to be
+ substitutable for dictionaries, such as the classes in the :mod:`shelve`
+ module.
+
+ Adding the mix-in as a superclass provides the full dictionary interface
+ whenever the class defines :meth:`__getitem__`, :meth:`__setitem__`,
+ :meth:`__delitem__`, and :meth:`keys`. For example::
+
+ >>> import UserDict
+ >>> class SeqDict(UserDict.DictMixin):
+ ... """Dictionary lookalike implemented with lists."""
+ ... def __init__(self):
+ ... self.keylist = []
+ ... self.valuelist = []
+ ... def __getitem__(self, key):
+ ... try:
+ ... i = self.keylist.index(key)
+ ... except ValueError:
+ ... raise KeyError
+ ... return self.valuelist[i]
+ ... def __setitem__(self, key, value):
+ ... try:
+ ... i = self.keylist.index(key)
+ ... self.valuelist[i] = value
+ ... except ValueError:
+ ... self.keylist.append(key)
+ ... self.valuelist.append(value)
+ ... def __delitem__(self, key):
+ ... try:
+ ... i = self.keylist.index(key)
+ ... except ValueError:
+ ... raise KeyError
+ ... self.keylist.pop(i)
+ ... self.valuelist.pop(i)
+ ... def keys(self):
+ ... return list(self.keylist)
+ ...
+ >>> s = SeqDict()
+ >>> dir(s) # See that other dictionary methods are implemented
+ ['__cmp__', '__contains__', '__delitem__', '__doc__', '__getitem__',
+ '__init__', '__iter__', '__len__', '__module__', '__repr__',
+ '__setitem__', 'clear', 'get', 'has_key', 'items', 'iteritems',
+ 'iterkeys', 'itervalues', 'keylist', 'keys', 'pop', 'popitem',
+ 'setdefault', 'update', 'valuelist', 'values']
+
+ (Contributed by Raymond Hettinger.)
+
+* The DOM implementation in :mod:`xml.dom.minidom` can now generate XML output
+ in a particular encoding by providing an optional encoding argument to the
+ :meth:`toxml` and :meth:`toprettyxml` methods of DOM nodes.
+
+* The :mod:`xmlrpclib` module now supports an XML-RPC extension for handling nil
+ data values such as Python's ``None``. Nil values are always supported on
+ unmarshalling an XML-RPC response. To generate requests containing ``None``,
+ you must supply a true value for the *allow_none* parameter when creating a
+ :class:`Marshaller` instance.
+
+* The new :mod:`DocXMLRPCServer` module allows writing self-documenting XML-RPC
+ servers. Run it in demo mode (as a program) to see it in action. Pointing the
+ Web browser to the RPC server produces pydoc-style documentation; pointing
+ xmlrpclib to the server allows invoking the actual methods. (Contributed by
+ Brian Quinlan.)
+
+* Support for internationalized domain names (RFCs 3454, 3490, 3491, and 3492)
+ has been added. The "idna" encoding can be used to convert between a Unicode
+ domain name and the ASCII-compatible encoding (ACE) of that name. ::
+
+ >{}>{}> u"www.Alliancefrançaise.nu".encode("idna")
+ 'www.xn--alliancefranaise-npb.nu'
+
+ The :mod:`socket` module has also been extended to transparently convert
+ Unicode hostnames to the ACE version before passing them to the C library.
+ Modules that deal with hostnames such as :mod:`httplib` and :mod:`ftplib`)
+ also support Unicode host names; :mod:`httplib` also sends HTTP ``Host``
+ headers using the ACE version of the domain name. :mod:`urllib` supports
+ Unicode URLs with non-ASCII host names as long as the ``path`` part of the URL
+ is ASCII only.
+
+ To implement this change, the :mod:`stringprep` module, the ``mkstringprep``
+ tool and the ``punycode`` encoding have been added.
+
+.. % ======================================================================
+
+
+Date/Time Type
+--------------
+
+Date and time types suitable for expressing timestamps were added as the
+:mod:`datetime` module. The types don't support different calendars or many
+fancy features, and just stick to the basics of representing time.
+
+The three primary types are: :class:`date`, representing a day, month, and year;
+:class:`time`, consisting of hour, minute, and second; and :class:`datetime`,
+which contains all the attributes of both :class:`date` and :class:`time`.
+There's also a :class:`timedelta` class representing differences between two
+points in time, and time zone logic is implemented by classes inheriting from
+the abstract :class:`tzinfo` class.
+
+You can create instances of :class:`date` and :class:`time` by either supplying
+keyword arguments to the appropriate constructor, e.g.
+``datetime.date(year=1972, month=10, day=15)``, or by using one of a number of
+class methods. For example, the :meth:`date.today` class method returns the
+current local date.
+
+Once created, instances of the date/time classes are all immutable. There are a
+number of methods for producing formatted strings from objects::
+
+ >>> import datetime
+ >>> now = datetime.datetime.now()
+ >>> now.isoformat()
+ '2002-12-30T21:27:03.994956'
+ >>> now.ctime() # Only available on date, datetime
+ 'Mon Dec 30 21:27:03 2002'
+ >>> now.strftime('%Y %d %b')
+ '2002 30 Dec'
+
+The :meth:`replace` method allows modifying one or more fields of a
+:class:`date` or :class:`datetime` instance, returning a new instance::
+
+ >>> d = datetime.datetime.now()
+ >>> d
+ datetime.datetime(2002, 12, 30, 22, 15, 38, 827738)
+ >>> d.replace(year=2001, hour = 12)
+ datetime.datetime(2001, 12, 30, 12, 15, 38, 827738)
+ >>>
+
+Instances can be compared, hashed, and converted to strings (the result is the
+same as that of :meth:`isoformat`). :class:`date` and :class:`datetime`
+instances can be subtracted from each other, and added to :class:`timedelta`
+instances. The largest missing feature is that there's no standard library
+support for parsing strings and getting back a :class:`date` or
+:class:`datetime`.
+
+For more information, refer to the module's reference documentation.
+(Contributed by Tim Peters.)
+
+.. % ======================================================================
+
+
+The optparse Module
+-------------------
+
+The :mod:`getopt` module provides simple parsing of command-line arguments. The
+new :mod:`optparse` module (originally named Optik) provides more elaborate
+command-line parsing that follows the Unix conventions, automatically creates
+the output for :option:`--help`, and can perform different actions for different
+options.
+
+You start by creating an instance of :class:`OptionParser` and telling it what
+your program's options are. ::
+
+ import sys
+ from optparse import OptionParser
+
+ op = OptionParser()
+ op.add_option('-i', '--input',
+ action='store', type='string', dest='input',
+ help='set input filename')
+ op.add_option('-l', '--length',
+ action='store', type='int', dest='length',
+ help='set maximum length of output')
+
+Parsing a command line is then done by calling the :meth:`parse_args` method. ::
+
+ options, args = op.parse_args(sys.argv[1:])
+ print options
+ print args
+
+This returns an object containing all of the option values, and a list of
+strings containing the remaining arguments.
+
+Invoking the script with the various arguments now works as you'd expect it to.
+Note that the length argument is automatically converted to an integer. ::
+
+ $ ./python opt.py -i data arg1
+ <Values at 0x400cad4c: {'input': 'data', 'length': None}>
+ ['arg1']
+ $ ./python opt.py --input=data --length=4
+ <Values at 0x400cad2c: {'input': 'data', 'length': 4}>
+ []
+ $
+
+The help message is automatically generated for you::
+
+ $ ./python opt.py --help
+ usage: opt.py [options]
+
+ options:
+ -h, --help show this help message and exit
+ -iINPUT, --input=INPUT
+ set input filename
+ -lLENGTH, --length=LENGTH
+ set maximum length of output
+ $
+
+See the module's documentation for more details.
+
+
+Optik was written by Greg Ward, with suggestions from the readers of the Getopt
+SIG.
+
+.. % ======================================================================
+
+
+.. _section-pymalloc:
+
+Pymalloc: A Specialized Object Allocator
+========================================
+
+Pymalloc, a specialized object allocator written by Vladimir Marangozov, was a
+feature added to Python 2.1. Pymalloc is intended to be faster than the system
+:cfunc:`malloc` and to have less memory overhead for allocation patterns typical
+of Python programs. The allocator uses C's :cfunc:`malloc` function to get large
+pools of memory and then fulfills smaller memory requests from these pools.
+
+In 2.1 and 2.2, pymalloc was an experimental feature and wasn't enabled by
+default; you had to explicitly enable it when compiling Python by providing the
+:option:`--with-pymalloc` option to the :program:`configure` script. In 2.3,
+pymalloc has had further enhancements and is now enabled by default; you'll have
+to supply :option:`--without-pymalloc` to disable it.
+
+This change is transparent to code written in Python; however, pymalloc may
+expose bugs in C extensions. Authors of C extension modules should test their
+code with pymalloc enabled, because some incorrect code may cause core dumps at
+runtime.
+
+There's one particularly common error that causes problems. There are a number
+of memory allocation functions in Python's C API that have previously just been
+aliases for the C library's :cfunc:`malloc` and :cfunc:`free`, meaning that if
+you accidentally called mismatched functions the error wouldn't be noticeable.
+When the object allocator is enabled, these functions aren't aliases of
+:cfunc:`malloc` and :cfunc:`free` any more, and calling the wrong function to
+free memory may get you a core dump. For example, if memory was allocated using
+:cfunc:`PyObject_Malloc`, it has to be freed using :cfunc:`PyObject_Free`, not
+:cfunc:`free`. A few modules included with Python fell afoul of this and had to
+be fixed; doubtless there are more third-party modules that will have the same
+problem.
+
+As part of this change, the confusing multiple interfaces for allocating memory
+have been consolidated down into two API families. Memory allocated with one
+family must not be manipulated with functions from the other family. There is
+one family for allocating chunks of memory and another family of functions
+specifically for allocating Python objects.
+
+* To allocate and free an undistinguished chunk of memory use the "raw memory"
+ family: :cfunc:`PyMem_Malloc`, :cfunc:`PyMem_Realloc`, and :cfunc:`PyMem_Free`.
+
+* The "object memory" family is the interface to the pymalloc facility described
+ above and is biased towards a large number of "small" allocations:
+ :cfunc:`PyObject_Malloc`, :cfunc:`PyObject_Realloc`, and :cfunc:`PyObject_Free`.
+
+* To allocate and free Python objects, use the "object" family
+ :cfunc:`PyObject_New`, :cfunc:`PyObject_NewVar`, and :cfunc:`PyObject_Del`.
+
+Thanks to lots of work by Tim Peters, pymalloc in 2.3 also provides debugging
+features to catch memory overwrites and doubled frees in both extension modules
+and in the interpreter itself. To enable this support, compile a debugging
+version of the Python interpreter by running :program:`configure` with
+:option:`--with-pydebug`.
+
+To aid extension writers, a header file :file:`Misc/pymemcompat.h` is
+distributed with the source to Python 2.3 that allows Python extensions to use
+the 2.3 interfaces to memory allocation while compiling against any version of
+Python since 1.5.2. You would copy the file from Python's source distribution
+and bundle it with the source of your extension.
+
+
+.. seealso::
+
+ http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/python/python/dist/src/Objects/obmalloc.c
+ For the full details of the pymalloc implementation, see the comments at the top
+ of the file :file:`Objects/obmalloc.c` in the Python source code. The above
+ link points to the file within the SourceForge CVS browser.
+
+.. % ======================================================================
+
+
+Build and C API Changes
+=======================
+
+Changes to Python's build process and to the C API include:
+
+* The cycle detection implementation used by the garbage collection has proven
+ to be stable, so it's now been made mandatory. You can no longer compile Python
+ without it, and the :option:`--with-cycle-gc` switch to :program:`configure` has
+ been removed.
+
+* Python can now optionally be built as a shared library
+ (:file:`libpython2.3.so`) by supplying :option:`--enable-shared` when running
+ Python's :program:`configure` script. (Contributed by Ondrej Palkovsky.)
+
+* The :cmacro:`DL_EXPORT` and :cmacro:`DL_IMPORT` macros are now deprecated.
+ Initialization functions for Python extension modules should now be declared
+ using the new macro :cmacro:`PyMODINIT_FUNC`, while the Python core will
+ generally use the :cmacro:`PyAPI_FUNC` and :cmacro:`PyAPI_DATA` macros.
+
+* The interpreter can be compiled without any docstrings for the built-in
+ functions and modules by supplying :option:`--without-doc-strings` to the
+ :program:`configure` script. This makes the Python executable about 10% smaller,
+ but will also mean that you can't get help for Python's built-ins. (Contributed
+ by Gustavo Niemeyer.)
+
+* The :cfunc:`PyArg_NoArgs` macro is now deprecated, and code that uses it
+ should be changed. For Python 2.2 and later, the method definition table can
+ specify the :const:`METH_NOARGS` flag, signalling that there are no arguments,
+ and the argument checking can then be removed. If compatibility with pre-2.2
+ versions of Python is important, the code could use ``PyArg_ParseTuple(args,
+ "")`` instead, but this will be slower than using :const:`METH_NOARGS`.
+
+* :cfunc:`PyArg_ParseTuple` accepts new format characters for various sizes of
+ unsigned integers: ``B`` for :ctype:`unsigned char`, ``H`` for :ctype:`unsigned
+ short int`, ``I`` for :ctype:`unsigned int`, and ``K`` for :ctype:`unsigned
+ long long`.
+
+* A new function, :cfunc:`PyObject_DelItemString(mapping, char \*key)` was added
+ as shorthand for ``PyObject_DelItem(mapping, PyString_New(key))``.
+
+* File objects now manage their internal string buffer differently, increasing
+ it exponentially when needed. This results in the benchmark tests in
+ :file:`Lib/test/test_bufio.py` speeding up considerably (from 57 seconds to 1.7
+ seconds, according to one measurement).
+
+* It's now possible to define class and static methods for a C extension type by
+ setting either the :const:`METH_CLASS` or :const:`METH_STATIC` flags in a
+ method's :ctype:`PyMethodDef` structure.
+
+* Python now includes a copy of the Expat XML parser's source code, removing any
+ dependence on a system version or local installation of Expat.
+
+* If you dynamically allocate type objects in your extension, you should be
+ aware of a change in the rules relating to the :attr:`__module__` and
+ :attr:`__name__` attributes. In summary, you will want to ensure the type's
+ dictionary contains a ``'__module__'`` key; making the module name the part of
+ the type name leading up to the final period will no longer have the desired
+ effect. For more detail, read the API reference documentation or the source.
+
+.. % ======================================================================
+
+
+Port-Specific Changes
+---------------------
+
+Support for a port to IBM's OS/2 using the EMX runtime environment was merged
+into the main Python source tree. EMX is a POSIX emulation layer over the OS/2
+system APIs. The Python port for EMX tries to support all the POSIX-like
+capability exposed by the EMX runtime, and mostly succeeds; :func:`fork` and
+:func:`fcntl` are restricted by the limitations of the underlying emulation
+layer. The standard OS/2 port, which uses IBM's Visual Age compiler, also
+gained support for case-sensitive import semantics as part of the integration of
+the EMX port into CVS. (Contributed by Andrew MacIntyre.)
+
+On MacOS, most toolbox modules have been weaklinked to improve backward
+compatibility. This means that modules will no longer fail to load if a single
+routine is missing on the current OS version. Instead calling the missing
+routine will raise an exception. (Contributed by Jack Jansen.)
+
+The RPM spec files, found in the :file:`Misc/RPM/` directory in the Python
+source distribution, were updated for 2.3. (Contributed by Sean Reifschneider.)
+
+Other new platforms now supported by Python include AtheOS
+(http://www.atheos.cx/), GNU/Hurd, and OpenVMS.
+
+.. % ======================================================================
+
+
+.. _section-other:
+
+Other Changes and Fixes
+=======================
+
+As usual, there were a bunch of other improvements and bugfixes scattered
+throughout the source tree. A search through the CVS change logs finds there
+were 523 patches applied and 514 bugs fixed between Python 2.2 and 2.3. Both
+figures are likely to be underestimates.
+
+Some of the more notable changes are:
+
+* If the :envvar:`PYTHONINSPECT` environment variable is set, the Python
+ interpreter will enter the interactive prompt after running a Python program, as
+ if Python had been invoked with the :option:`-i` option. The environment
+ variable can be set before running the Python interpreter, or it can be set by
+ the Python program as part of its execution.
+
+* The :file:`regrtest.py` script now provides a way to allow "all resources
+ except *foo*." A resource name passed to the :option:`-u` option can now be
+ prefixed with a hyphen (``'-'``) to mean "remove this resource." For example,
+ the option '``-uall,-bsddb``' could be used to enable the use of all resources
+ except ``bsddb``.
+
+* The tools used to build the documentation now work under Cygwin as well as
+ Unix.
+
+* The ``SET_LINENO`` opcode has been removed. Back in the mists of time, this
+ opcode was needed to produce line numbers in tracebacks and support trace
+ functions (for, e.g., :mod:`pdb`). Since Python 1.5, the line numbers in
+ tracebacks have been computed using a different mechanism that works with
+ "python -O". For Python 2.3 Michael Hudson implemented a similar scheme to
+ determine when to call the trace function, removing the need for ``SET_LINENO``
+ entirely.
+
+ It would be difficult to detect any resulting difference from Python code, apart
+ from a slight speed up when Python is run without :option:`-O`.
+
+ C extensions that access the :attr:`f_lineno` field of frame objects should
+ instead call ``PyCode_Addr2Line(f->f_code, f->f_lasti)``. This will have the
+ added effect of making the code work as desired under "python -O" in earlier
+ versions of Python.
+
+ A nifty new feature is that trace functions can now assign to the
+ :attr:`f_lineno` attribute of frame objects, changing the line that will be
+ executed next. A ``jump`` command has been added to the :mod:`pdb` debugger
+ taking advantage of this new feature. (Implemented by Richie Hindle.)
+
+.. % ======================================================================
+
+
+Porting to Python 2.3
+=====================
+
+This section lists previously described changes that may require changes to your
+code:
+
+* :keyword:`yield` is now always a keyword; if it's used as a variable name in
+ your code, a different name must be chosen.
+
+* For strings *X* and *Y*, ``X in Y`` now works if *X* is more than one
+ character long.
+
+* The :func:`int` type constructor will now return a long integer instead of
+ raising an :exc:`OverflowError` when a string or floating-point number is too
+ large to fit into an integer.
+
+* If you have Unicode strings that contain 8-bit characters, you must declare
+ the file's encoding (UTF-8, Latin-1, or whatever) by adding a comment to the top
+ of the file. See section :ref:`section-encodings` for more information.
+
+* Calling Tcl methods through :mod:`_tkinter` no longer returns only strings.
+ Instead, if Tcl returns other objects those objects are converted to their
+ Python equivalent, if one exists, or wrapped with a :class:`_tkinter.Tcl_Obj`
+ object if no Python equivalent exists.
+
+* Large octal and hex literals such as ``0xffffffff`` now trigger a
+ :exc:`FutureWarning`. Currently they're stored as 32-bit numbers and result in a
+ negative value, but in Python 2.4 they'll become positive long integers.
+
+ There are a few ways to fix this warning. If you really need a positive number,
+ just add an ``L`` to the end of the literal. If you're trying to get a 32-bit
+ integer with low bits set and have previously used an expression such as ``~(1
+ << 31)``, it's probably clearest to start with all bits set and clear the
+ desired upper bits. For example, to clear just the top bit (bit 31), you could
+ write ``0xffffffffL &~(1L<<31)``.
+
+ .. % The empty groups below prevent conversion to guillemets.
+
+* You can no longer disable assertions by assigning to ``__debug__``.
+
+* The Distutils :func:`setup` function has gained various new keyword arguments
+ such as *depends*. Old versions of the Distutils will abort if passed unknown
+ keywords. A solution is to check for the presence of the new
+ :func:`get_distutil_options` function in your :file:`setup.py` and only uses the
+ new keywords with a version of the Distutils that supports them::
+
+ from distutils import core
+
+ kw = {'sources': 'foo.c', ...}
+ if hasattr(core, 'get_distutil_options'):
+ kw['depends'] = ['foo.h']
+ ext = Extension(**kw)
+
+* Using ``None`` as a variable name will now result in a :exc:`SyntaxWarning`
+ warning.
+
+* Names of extension types defined by the modules included with Python now
+ contain the module and a ``'.'`` in front of the type name.
+
+.. % ======================================================================
+
+
+.. _acks:
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: Jeff Bauer,
+Simon Brunning, Brett Cannon, Michael Chermside, Andrew Dalke, Scott David
+Daniels, Fred L. Drake, Jr., David Fraser, Kelly Gerber, Raymond Hettinger,
+Michael Hudson, Chris Lambert, Detlef Lannert, Martin von Löwis, Andrew
+MacIntyre, Lalo Martins, Chad Netzer, Gustavo Niemeyer, Neal Norwitz, Hans
+Nowak, Chris Reedy, Francesco Ricciardi, Vinay Sajip, Neil Schemenauer, Roman
+Suzi, Jason Tishler, Just van Rossum.
+
diff --git a/Doc/whatsnew/2.4.rst b/Doc/whatsnew/2.4.rst
new file mode 100644
index 0000000000..d782f5d8d6
--- /dev/null
+++ b/Doc/whatsnew/2.4.rst
@@ -0,0 +1,1571 @@
+****************************
+ What's New in Python 2.4
+****************************
+
+:Author: A.M. Kuchling
+
+.. |release| replace:: 1.02
+
+.. % $Id: whatsnew24.tex 55005 2007-04-27 19:54:29Z guido.van.rossum $
+.. % Don't write extensive text for new sections; I'll do that.
+.. % Feel free to add commented-out reminders of things that need
+.. % to be covered. --amk
+
+This article explains the new features in Python 2.4.1, released on March 30,
+2005.
+
+Python 2.4 is a medium-sized release. It doesn't introduce as many changes as
+the radical Python 2.2, but introduces more features than the conservative 2.3
+release. The most significant new language features are function decorators and
+generator expressions; most other changes are to the standard library.
+
+According to the CVS change logs, there were 481 patches applied and 502 bugs
+fixed between Python 2.3 and 2.4. Both figures are likely to be underestimates.
+
+This article doesn't attempt to provide a complete specification of every single
+new feature, but instead provides a brief introduction to each feature. For
+full details, you should refer to the documentation for Python 2.4, such as the
+Python Library Reference and the Python Reference Manual. Often you will be
+referred to the PEP for a particular new feature for explanations of the
+implementation and design rationale.
+
+.. % ======================================================================
+
+
+PEP 218: Built-In Set Objects
+=============================
+
+Python 2.3 introduced the :mod:`sets` module. C implementations of set data
+types have now been added to the Python core as two new built-in types,
+:func:`set(iterable)` and :func:`frozenset(iterable)`. They provide high speed
+operations for membership testing, for eliminating duplicates from sequences,
+and for mathematical operations like unions, intersections, differences, and
+symmetric differences. ::
+
+ >>> a = set('abracadabra') # form a set from a string
+ >>> 'z' in a # fast membership testing
+ False
+ >>> a # unique letters in a
+ set(['a', 'r', 'b', 'c', 'd'])
+ >>> ''.join(a) # convert back into a string
+ 'arbcd'
+
+ >>> b = set('alacazam') # form a second set
+ >>> a - b # letters in a but not in b
+ set(['r', 'd', 'b'])
+ >>> a | b # letters in either a or b
+ set(['a', 'c', 'r', 'd', 'b', 'm', 'z', 'l'])
+ >>> a & b # letters in both a and b
+ set(['a', 'c'])
+ >>> a ^ b # letters in a or b but not both
+ set(['r', 'd', 'b', 'm', 'z', 'l'])
+
+ >>> a.add('z') # add a new element
+ >>> a.update('wxy') # add multiple new elements
+ >>> a
+ set(['a', 'c', 'b', 'd', 'r', 'w', 'y', 'x', 'z'])
+ >>> a.remove('x') # take one element out
+ >>> a
+ set(['a', 'c', 'b', 'd', 'r', 'w', 'y', 'z'])
+
+The :func:`frozenset` type is an immutable version of :func:`set`. Since it is
+immutable and hashable, it may be used as a dictionary key or as a member of
+another set.
+
+The :mod:`sets` module remains in the standard library, and may be useful if you
+wish to subclass the :class:`Set` or :class:`ImmutableSet` classes. There are
+currently no plans to deprecate the module.
+
+
+.. seealso::
+
+ :pep:`218` - Adding a Built-In Set Object Type
+ Originally proposed by Greg Wilson and ultimately implemented by Raymond
+ Hettinger.
+
+.. % ======================================================================
+
+
+PEP 237: Unifying Long Integers and Integers
+============================================
+
+The lengthy transition process for this PEP, begun in Python 2.2, takes another
+step forward in Python 2.4. In 2.3, certain integer operations that would
+behave differently after int/long unification triggered :exc:`FutureWarning`
+warnings and returned values limited to 32 or 64 bits (depending on your
+platform). In 2.4, these expressions no longer produce a warning and instead
+produce a different result that's usually a long integer.
+
+The problematic expressions are primarily left shifts and lengthy hexadecimal
+and octal constants. For example, ``2 << 32`` results in a warning in 2.3,
+evaluating to 0 on 32-bit platforms. In Python 2.4, this expression now returns
+the correct answer, 8589934592.
+
+
+.. seealso::
+
+ :pep:`237` - Unifying Long Integers and Integers
+ Original PEP written by Moshe Zadka and GvR. The changes for 2.4 were
+ implemented by Kalle Svensson.
+
+.. % ======================================================================
+
+
+PEP 289: Generator Expressions
+==============================
+
+The iterator feature introduced in Python 2.2 and the :mod:`itertools` module
+make it easier to write programs that loop through large data sets without
+having the entire data set in memory at one time. List comprehensions don't fit
+into this picture very well because they produce a Python list object containing
+all of the items. This unavoidably pulls all of the objects into memory, which
+can be a problem if your data set is very large. When trying to write a
+functionally-styled program, it would be natural to write something like::
+
+ links = [link for link in get_all_links() if not link.followed]
+ for link in links:
+ ...
+
+instead of ::
+
+ for link in get_all_links():
+ if link.followed:
+ continue
+ ...
+
+The first form is more concise and perhaps more readable, but if you're dealing
+with a large number of link objects you'd have to write the second form to avoid
+having all link objects in memory at the same time.
+
+Generator expressions work similarly to list comprehensions but don't
+materialize the entire list; instead they create a generator that will return
+elements one by one. The above example could be written as::
+
+ links = (link for link in get_all_links() if not link.followed)
+ for link in links:
+ ...
+
+Generator expressions always have to be written inside parentheses, as in the
+above example. The parentheses signalling a function call also count, so if you
+want to create an iterator that will be immediately passed to a function you
+could write::
+
+ print sum(obj.count for obj in list_all_objects())
+
+Generator expressions differ from list comprehensions in various small ways.
+Most notably, the loop variable (*obj* in the above example) is not accessible
+outside of the generator expression. List comprehensions leave the variable
+assigned to its last value; future versions of Python will change this, making
+list comprehensions match generator expressions in this respect.
+
+
+.. seealso::
+
+ :pep:`289` - Generator Expressions
+ Proposed by Raymond Hettinger and implemented by Jiwon Seo with early efforts
+ steered by Hye-Shik Chang.
+
+.. % ======================================================================
+
+
+PEP 292: Simpler String Substitutions
+=====================================
+
+Some new classes in the standard library provide an alternative mechanism for
+substituting variables into strings; this style of substitution may be better
+for applications where untrained users need to edit templates.
+
+The usual way of substituting variables by name is the ``%`` operator::
+
+ >>> '%(page)i: %(title)s' % {'page':2, 'title': 'The Best of Times'}
+ '2: The Best of Times'
+
+When writing the template string, it can be easy to forget the ``i`` or ``s``
+after the closing parenthesis. This isn't a big problem if the template is in a
+Python module, because you run the code, get an "Unsupported format character"
+:exc:`ValueError`, and fix the problem. However, consider an application such
+as Mailman where template strings or translations are being edited by users who
+aren't aware of the Python language. The format string's syntax is complicated
+to explain to such users, and if they make a mistake, it's difficult to provide
+helpful feedback to them.
+
+PEP 292 adds a :class:`Template` class to the :mod:`string` module that uses
+``$`` to indicate a substitution::
+
+ >>> import string
+ >>> t = string.Template('$page: $title')
+ >>> t.substitute({'page':2, 'title': 'The Best of Times'})
+ '2: The Best of Times'
+
+If a key is missing from the dictionary, the :meth:`substitute` method will
+raise a :exc:`KeyError`. There's also a :meth:`safe_substitute` method that
+ignores missing keys:
+
+.. % $ Terminate $-mode for Emacs
+
+::
+
+ >>> t = string.Template('$page: $title')
+ >>> t.safe_substitute({'page':3})
+ '3: $title'
+
+.. % $ Terminate math-mode for Emacs
+
+
+.. seealso::
+
+ :pep:`292` - Simpler String Substitutions
+ Written and implemented by Barry Warsaw.
+
+.. % ======================================================================
+
+
+PEP 318: Decorators for Functions and Methods
+=============================================
+
+Python 2.2 extended Python's object model by adding static methods and class
+methods, but it didn't extend Python's syntax to provide any new way of defining
+static or class methods. Instead, you had to write a :keyword:`def` statement
+in the usual way, and pass the resulting method to a :func:`staticmethod` or
+:func:`classmethod` function that would wrap up the function as a method of the
+new type. Your code would look like this::
+
+ class C:
+ def meth (cls):
+ ...
+
+ meth = classmethod(meth) # Rebind name to wrapped-up class method
+
+If the method was very long, it would be easy to miss or forget the
+:func:`classmethod` invocation after the function body.
+
+The intention was always to add some syntax to make such definitions more
+readable, but at the time of 2.2's release a good syntax was not obvious. Today
+a good syntax *still* isn't obvious but users are asking for easier access to
+the feature; a new syntactic feature has been added to meet this need.
+
+The new feature is called "function decorators". The name comes from the idea
+that :func:`classmethod`, :func:`staticmethod`, and friends are storing
+additional information on a function object; they're *decorating* functions with
+more details.
+
+The notation borrows from Java and uses the ``'@'`` character as an indicator.
+Using the new syntax, the example above would be written::
+
+ class C:
+
+ @classmethod
+ def meth (cls):
+ ...
+
+
+The ``@classmethod`` is shorthand for the ``meth=classmethod(meth)`` assignment.
+More generally, if you have the following::
+
+ @A
+ @B
+ @C
+ def f ():
+ ...
+
+It's equivalent to the following pre-decorator code::
+
+ def f(): ...
+ f = A(B(C(f)))
+
+Decorators must come on the line before a function definition, one decorator per
+line, and can't be on the same line as the def statement, meaning that ``@A def
+f(): ...`` is illegal. You can only decorate function definitions, either at
+the module level or inside a class; you can't decorate class definitions.
+
+A decorator is just a function that takes the function to be decorated as an
+argument and returns either the same function or some new object. The return
+value of the decorator need not be callable (though it typically is), unless
+further decorators will be applied to the result. It's easy to write your own
+decorators. The following simple example just sets an attribute on the function
+object::
+
+ >>> def deco(func):
+ ... func.attr = 'decorated'
+ ... return func
+ ...
+ >>> @deco
+ ... def f(): pass
+ ...
+ >>> f
+ <function f at 0x402ef0d4>
+ >>> f.attr
+ 'decorated'
+ >>>
+
+As a slightly more realistic example, the following decorator checks that the
+supplied argument is an integer::
+
+ def require_int (func):
+ def wrapper (arg):
+ assert isinstance(arg, int)
+ return func(arg)
+
+ return wrapper
+
+ @require_int
+ def p1 (arg):
+ print arg
+
+ @require_int
+ def p2(arg):
+ print arg*2
+
+An example in :pep:`318` contains a fancier version of this idea that lets you
+both specify the required type and check the returned type.
+
+Decorator functions can take arguments. If arguments are supplied, your
+decorator function is called with only those arguments and must return a new
+decorator function; this function must take a single function and return a
+function, as previously described. In other words, ``@A @B @C(args)`` becomes::
+
+ def f(): ...
+ _deco = C(args)
+ f = A(B(_deco(f)))
+
+Getting this right can be slightly brain-bending, but it's not too difficult.
+
+A small related change makes the :attr:`func_name` attribute of functions
+writable. This attribute is used to display function names in tracebacks, so
+decorators should change the name of any new function that's constructed and
+returned.
+
+
+.. seealso::
+
+ :pep:`318` - Decorators for Functions, Methods and Classes
+ Written by Kevin D. Smith, Jim Jewett, and Skip Montanaro. Several people
+ wrote patches implementing function decorators, but the one that was actually
+ checked in was patch #979728, written by Mark Russell.
+
+ http://www.python.org/moin/PythonDecoratorLibrary
+ This Wiki page contains several examples of decorators.
+
+.. % ======================================================================
+
+
+PEP 322: Reverse Iteration
+==========================
+
+A new built-in function, :func:`reversed(seq)`, takes a sequence and returns an
+iterator that loops over the elements of the sequence in reverse order. ::
+
+ >>> for i in reversed(xrange(1,4)):
+ ... print i
+ ...
+ 3
+ 2
+ 1
+
+Compared to extended slicing, such as ``range(1,4)[::-1]``, :func:`reversed` is
+easier to read, runs faster, and uses substantially less memory.
+
+Note that :func:`reversed` only accepts sequences, not arbitrary iterators. If
+you want to reverse an iterator, first convert it to a list with :func:`list`.
+::
+
+ >>> input = open('/etc/passwd', 'r')
+ >>> for line in reversed(list(input)):
+ ... print line
+ ...
+ root:*:0:0:System Administrator:/var/root:/bin/tcsh
+ ...
+
+
+.. seealso::
+
+ :pep:`322` - Reverse Iteration
+ Written and implemented by Raymond Hettinger.
+
+.. % ======================================================================
+
+
+PEP 324: New subprocess Module
+==============================
+
+The standard library provides a number of ways to execute a subprocess, offering
+different features and different levels of complexity.
+:func:`os.system(command)` is easy to use, but slow (it runs a shell process
+which executes the command) and dangerous (you have to be careful about escaping
+the shell's metacharacters). The :mod:`popen2` module offers classes that can
+capture standard output and standard error from the subprocess, but the naming
+is confusing. The :mod:`subprocess` module cleans this up, providing a unified
+interface that offers all the features you might need.
+
+Instead of :mod:`popen2`'s collection of classes, :mod:`subprocess` contains a
+single class called :class:`Popen` whose constructor supports a number of
+different keyword arguments. ::
+
+ class Popen(args, bufsize=0, executable=None,
+ stdin=None, stdout=None, stderr=None,
+ preexec_fn=None, close_fds=False, shell=False,
+ cwd=None, env=None, universal_newlines=False,
+ startupinfo=None, creationflags=0):
+
+*args* is commonly a sequence of strings that will be the arguments to the
+program executed as the subprocess. (If the *shell* argument is true, *args*
+can be a string which will then be passed on to the shell for interpretation,
+just as :func:`os.system` does.)
+
+*stdin*, *stdout*, and *stderr* specify what the subprocess's input, output, and
+error streams will be. You can provide a file object or a file descriptor, or
+you can use the constant ``subprocess.PIPE`` to create a pipe between the
+subprocess and the parent.
+
+The constructor has a number of handy options:
+
+* *close_fds* requests that all file descriptors be closed before running the
+ subprocess.
+
+* *cwd* specifies the working directory in which the subprocess will be executed
+ (defaulting to whatever the parent's working directory is).
+
+* *env* is a dictionary specifying environment variables.
+
+* *preexec_fn* is a function that gets called before the child is started.
+
+* *universal_newlines* opens the child's input and output using Python's
+ universal newline feature.
+
+Once you've created the :class:`Popen` instance, you can call its :meth:`wait`
+method to pause until the subprocess has exited, :meth:`poll` to check if it's
+exited without pausing, or :meth:`communicate(data)` to send the string *data*
+to the subprocess's standard input. :meth:`communicate(data)` then reads any
+data that the subprocess has sent to its standard output or standard error,
+returning a tuple ``(stdout_data, stderr_data)``.
+
+:func:`call` is a shortcut that passes its arguments along to the :class:`Popen`
+constructor, waits for the command to complete, and returns the status code of
+the subprocess. It can serve as a safer analog to :func:`os.system`::
+
+ sts = subprocess.call(['dpkg', '-i', '/tmp/new-package.deb'])
+ if sts == 0:
+ # Success
+ ...
+ else:
+ # dpkg returned an error
+ ...
+
+The command is invoked without use of the shell. If you really do want to use
+the shell, you can add ``shell=True`` as a keyword argument and provide a string
+instead of a sequence::
+
+ sts = subprocess.call('dpkg -i /tmp/new-package.deb', shell=True)
+
+The PEP takes various examples of shell and Python code and shows how they'd be
+translated into Python code that uses :mod:`subprocess`. Reading this section
+of the PEP is highly recommended.
+
+
+.. seealso::
+
+ :pep:`324` - subprocess - New process module
+ Written and implemented by Peter Åstrand, with assistance from Fredrik Lundh and
+ others.
+
+.. % ======================================================================
+
+
+PEP 327: Decimal Data Type
+==========================
+
+Python has always supported floating-point (FP) numbers, based on the underlying
+C :ctype:`double` type, as a data type. However, while most programming
+languages provide a floating-point type, many people (even programmers) are
+unaware that floating-point numbers don't represent certain decimal fractions
+accurately. The new :class:`Decimal` type can represent these fractions
+accurately, up to a user-specified precision limit.
+
+
+Why is Decimal needed?
+----------------------
+
+The limitations arise from the representation used for floating-point numbers.
+FP numbers are made up of three components:
+
+* The sign, which is positive or negative.
+
+* The mantissa, which is a single-digit binary number followed by a fractional
+ part. For example, ``1.01`` in base-2 notation is ``1 + 0/2 + 1/4``, or 1.25 in
+ decimal notation.
+
+* The exponent, which tells where the decimal point is located in the number
+ represented.
+
+For example, the number 1.25 has positive sign, a mantissa value of 1.01 (in
+binary), and an exponent of 0 (the decimal point doesn't need to be shifted).
+The number 5 has the same sign and mantissa, but the exponent is 2 because the
+mantissa is multiplied by 4 (2 to the power of the exponent 2); 1.25 \* 4 equals
+5.
+
+Modern systems usually provide floating-point support that conforms to a
+standard called IEEE 754. C's :ctype:`double` type is usually implemented as a
+64-bit IEEE 754 number, which uses 52 bits of space for the mantissa. This
+means that numbers can only be specified to 52 bits of precision. If you're
+trying to represent numbers whose expansion repeats endlessly, the expansion is
+cut off after 52 bits. Unfortunately, most software needs to produce output in
+base 10, and common fractions in base 10 are often repeating decimals in binary.
+For example, 1.1 decimal is binary ``1.0001100110011 ...``; .1 = 1/16 + 1/32 +
+1/256 plus an infinite number of additional terms. IEEE 754 has to chop off
+that infinitely repeated decimal after 52 digits, so the representation is
+slightly inaccurate.
+
+Sometimes you can see this inaccuracy when the number is printed::
+
+ >>> 1.1
+ 1.1000000000000001
+
+The inaccuracy isn't always visible when you print the number because the FP-to-
+decimal-string conversion is provided by the C library, and most C libraries try
+to produce sensible output. Even if it's not displayed, however, the inaccuracy
+is still there and subsequent operations can magnify the error.
+
+For many applications this doesn't matter. If I'm plotting points and
+displaying them on my monitor, the difference between 1.1 and 1.1000000000000001
+is too small to be visible. Reports often limit output to a certain number of
+decimal places, and if you round the number to two or three or even eight
+decimal places, the error is never apparent. However, for applications where it
+does matter, it's a lot of work to implement your own custom arithmetic
+routines.
+
+Hence, the :class:`Decimal` type was created.
+
+
+The :class:`Decimal` type
+-------------------------
+
+A new module, :mod:`decimal`, was added to Python's standard library. It
+contains two classes, :class:`Decimal` and :class:`Context`. :class:`Decimal`
+instances represent numbers, and :class:`Context` instances are used to wrap up
+various settings such as the precision and default rounding mode.
+
+:class:`Decimal` instances are immutable, like regular Python integers and FP
+numbers; once it's been created, you can't change the value an instance
+represents. :class:`Decimal` instances can be created from integers or
+strings::
+
+ >>> import decimal
+ >>> decimal.Decimal(1972)
+ Decimal("1972")
+ >>> decimal.Decimal("1.1")
+ Decimal("1.1")
+
+You can also provide tuples containing the sign, the mantissa represented as a
+tuple of decimal digits, and the exponent::
+
+ >>> decimal.Decimal((1, (1, 4, 7, 5), -2))
+ Decimal("-14.75")
+
+Cautionary note: the sign bit is a Boolean value, so 0 is positive and 1 is
+negative.
+
+Converting from floating-point numbers poses a bit of a problem: should the FP
+number representing 1.1 turn into the decimal number for exactly 1.1, or for 1.1
+plus whatever inaccuracies are introduced? The decision was to dodge the issue
+and leave such a conversion out of the API. Instead, you should convert the
+floating-point number into a string using the desired precision and pass the
+string to the :class:`Decimal` constructor::
+
+ >>> f = 1.1
+ >>> decimal.Decimal(str(f))
+ Decimal("1.1")
+ >>> decimal.Decimal('%.12f' % f)
+ Decimal("1.100000000000")
+
+Once you have :class:`Decimal` instances, you can perform the usual mathematical
+operations on them. One limitation: exponentiation requires an integer
+exponent::
+
+ >>> a = decimal.Decimal('35.72')
+ >>> b = decimal.Decimal('1.73')
+ >>> a+b
+ Decimal("37.45")
+ >>> a-b
+ Decimal("33.99")
+ >>> a*b
+ Decimal("61.7956")
+ >>> a/b
+ Decimal("20.64739884393063583815028902")
+ >>> a ** 2
+ Decimal("1275.9184")
+ >>> a**b
+ Traceback (most recent call last):
+ ...
+ decimal.InvalidOperation: x ** (non-integer)
+
+You can combine :class:`Decimal` instances with integers, but not with floating-
+point numbers::
+
+ >>> a + 4
+ Decimal("39.72")
+ >>> a + 4.5
+ Traceback (most recent call last):
+ ...
+ TypeError: You can interact Decimal only with int, long or Decimal data types.
+ >>>
+
+:class:`Decimal` numbers can be used with the :mod:`math` and :mod:`cmath`
+modules, but note that they'll be immediately converted to floating-point
+numbers before the operation is performed, resulting in a possible loss of
+precision and accuracy. You'll also get back a regular floating-point number
+and not a :class:`Decimal`. ::
+
+ >>> import math, cmath
+ >>> d = decimal.Decimal('123456789012.345')
+ >>> math.sqrt(d)
+ 351364.18288201344
+ >>> cmath.sqrt(-d)
+ 351364.18288201344j
+
+:class:`Decimal` instances have a :meth:`sqrt` method that returns a
+:class:`Decimal`, but if you need other things such as trigonometric functions
+you'll have to implement them. ::
+
+ >>> d.sqrt()
+ Decimal("351364.1828820134592177245001")
+
+
+The :class:`Context` type
+-------------------------
+
+Instances of the :class:`Context` class encapsulate several settings for
+decimal operations:
+
+* :attr:`prec` is the precision, the number of decimal places.
+
+* :attr:`rounding` specifies the rounding mode. The :mod:`decimal` module has
+ constants for the various possibilities: :const:`ROUND_DOWN`,
+ :const:`ROUND_CEILING`, :const:`ROUND_HALF_EVEN`, and various others.
+
+* :attr:`traps` is a dictionary specifying what happens on encountering certain
+ error conditions: either an exception is raised or a value is returned. Some
+ examples of error conditions are division by zero, loss of precision, and
+ overflow.
+
+There's a thread-local default context available by calling :func:`getcontext`;
+you can change the properties of this context to alter the default precision,
+rounding, or trap handling. The following example shows the effect of changing
+the precision of the default context::
+
+ >>> decimal.getcontext().prec
+ 28
+ >>> decimal.Decimal(1) / decimal.Decimal(7)
+ Decimal("0.1428571428571428571428571429")
+ >>> decimal.getcontext().prec = 9
+ >>> decimal.Decimal(1) / decimal.Decimal(7)
+ Decimal("0.142857143")
+
+The default action for error conditions is selectable; the module can either
+return a special value such as infinity or not-a-number, or exceptions can be
+raised::
+
+ >>> decimal.Decimal(1) / decimal.Decimal(0)
+ Traceback (most recent call last):
+ ...
+ decimal.DivisionByZero: x / 0
+ >>> decimal.getcontext().traps[decimal.DivisionByZero] = False
+ >>> decimal.Decimal(1) / decimal.Decimal(0)
+ Decimal("Infinity")
+ >>>
+
+The :class:`Context` instance also has various methods for formatting numbers
+such as :meth:`to_eng_string` and :meth:`to_sci_string`.
+
+For more information, see the documentation for the :mod:`decimal` module, which
+includes a quick-start tutorial and a reference.
+
+
+.. seealso::
+
+ :pep:`327` - Decimal Data Type
+ Written by Facundo Batista and implemented by Facundo Batista, Eric Price,
+ Raymond Hettinger, Aahz, and Tim Peters.
+
+ http://research.microsoft.com/~hollasch/cgindex/coding/ieeefloat.html
+ A more detailed overview of the IEEE-754 representation.
+
+ http://www.lahey.com/float.htm
+ The article uses Fortran code to illustrate many of the problems that floating-
+ point inaccuracy can cause.
+
+ http://www2.hursley.ibm.com/decimal/
+ A description of a decimal-based representation. This representation is being
+ proposed as a standard, and underlies the new Python decimal type. Much of this
+ material was written by Mike Cowlishaw, designer of the Rexx language.
+
+.. % ======================================================================
+
+
+PEP 328: Multi-line Imports
+===========================
+
+One language change is a small syntactic tweak aimed at making it easier to
+import many names from a module. In a ``from module import names`` statement,
+*names* is a sequence of names separated by commas. If the sequence is very
+long, you can either write multiple imports from the same module, or you can use
+backslashes to escape the line endings like this::
+
+ from SimpleXMLRPCServer import SimpleXMLRPCServer,\
+ SimpleXMLRPCRequestHandler,\
+ CGIXMLRPCRequestHandler,\
+ resolve_dotted_attribute
+
+The syntactic change in Python 2.4 simply allows putting the names within
+parentheses. Python ignores newlines within a parenthesized expression, so the
+backslashes are no longer needed::
+
+ from SimpleXMLRPCServer import (SimpleXMLRPCServer,
+ SimpleXMLRPCRequestHandler,
+ CGIXMLRPCRequestHandler,
+ resolve_dotted_attribute)
+
+The PEP also proposes that all :keyword:`import` statements be absolute imports,
+with a leading ``.`` character to indicate a relative import. This part of the
+PEP was not implemented for Python 2.4, but was completed for Python 2.5.
+
+
+.. seealso::
+
+ :pep:`328` - Imports: Multi-Line and Absolute/Relative
+ Written by Aahz. Multi-line imports were implemented by Dima Dorfman.
+
+.. % ======================================================================
+
+
+PEP 331: Locale-Independent Float/String Conversions
+====================================================
+
+The :mod:`locale` modules lets Python software select various conversions and
+display conventions that are localized to a particular country or language.
+However, the module was careful to not change the numeric locale because various
+functions in Python's implementation required that the numeric locale remain set
+to the ``'C'`` locale. Often this was because the code was using the C
+library's :cfunc:`atof` function.
+
+Not setting the numeric locale caused trouble for extensions that used third-
+party C libraries, however, because they wouldn't have the correct locale set.
+The motivating example was GTK+, whose user interface widgets weren't displaying
+numbers in the current locale.
+
+The solution described in the PEP is to add three new functions to the Python
+API that perform ASCII-only conversions, ignoring the locale setting:
+
+* :cfunc:`PyOS_ascii_strtod(str, ptr)` and :cfunc:`PyOS_ascii_atof(str, ptr)`
+ both convert a string to a C :ctype:`double`.
+
+* :cfunc:`PyOS_ascii_formatd(buffer, buf_len, format, d)` converts a
+ :ctype:`double` to an ASCII string.
+
+The code for these functions came from the GLib library
+(http://developer.gnome.org/arch/gtk/glib.html), whose developers kindly
+relicensed the relevant functions and donated them to the Python Software
+Foundation. The :mod:`locale` module can now change the numeric locale,
+letting extensions such as GTK+ produce the correct results.
+
+
+.. seealso::
+
+ :pep:`331` - Locale-Independent Float/String Conversions
+ Written by Christian R. Reis, and implemented by Gustavo Carneiro.
+
+.. % ======================================================================
+
+
+Other Language Changes
+======================
+
+Here are all of the changes that Python 2.4 makes to the core Python language.
+
+* Decorators for functions and methods were added (:pep:`318`).
+
+* Built-in :func:`set` and :func:`frozenset` types were added (:pep:`218`).
+ Other new built-ins include the :func:`reversed(seq)` function (:pep:`322`).
+
+* Generator expressions were added (:pep:`289`).
+
+* Certain numeric expressions no longer return values restricted to 32 or 64
+ bits (:pep:`237`).
+
+* You can now put parentheses around the list of names in a ``from module import
+ names`` statement (:pep:`328`).
+
+* The :meth:`dict.update` method now accepts the same argument forms as the
+ :class:`dict` constructor. This includes any mapping, any iterable of key/value
+ pairs, and keyword arguments. (Contributed by Raymond Hettinger.)
+
+* The string methods :meth:`ljust`, :meth:`rjust`, and :meth:`center` now take
+ an optional argument for specifying a fill character other than a space.
+ (Contributed by Raymond Hettinger.)
+
+* Strings also gained an :meth:`rsplit` method that works like the :meth:`split`
+ method but splits from the end of the string. (Contributed by Sean
+ Reifschneider.) ::
+
+ >>> 'www.python.org'.split('.', 1)
+ ['www', 'python.org']
+ 'www.python.org'.rsplit('.', 1)
+ ['www.python', 'org']
+
+* Three keyword parameters, *cmp*, *key*, and *reverse*, were added to the
+ :meth:`sort` method of lists. These parameters make some common usages of
+ :meth:`sort` simpler. All of these parameters are optional.
+
+ For the *cmp* parameter, the value should be a comparison function that takes
+ two parameters and returns -1, 0, or +1 depending on how the parameters compare.
+ This function will then be used to sort the list. Previously this was the only
+ parameter that could be provided to :meth:`sort`.
+
+ *key* should be a single-parameter function that takes a list element and
+ returns a comparison key for the element. The list is then sorted using the
+ comparison keys. The following example sorts a list case-insensitively::
+
+ >>> L = ['A', 'b', 'c', 'D']
+ >>> L.sort() # Case-sensitive sort
+ >>> L
+ ['A', 'D', 'b', 'c']
+ >>> # Using 'key' parameter to sort list
+ >>> L.sort(key=lambda x: x.lower())
+ >>> L
+ ['A', 'b', 'c', 'D']
+ >>> # Old-fashioned way
+ >>> L.sort(cmp=lambda x,y: cmp(x.lower(), y.lower()))
+ >>> L
+ ['A', 'b', 'c', 'D']
+
+ The last example, which uses the *cmp* parameter, is the old way to perform a
+ case-insensitive sort. It works but is slower than using a *key* parameter.
+ Using *key* calls :meth:`lower` method once for each element in the list while
+ using *cmp* will call it twice for each comparison, so using *key* saves on
+ invocations of the :meth:`lower` method.
+
+ For simple key functions and comparison functions, it is often possible to avoid
+ a :keyword:`lambda` expression by using an unbound method instead. For example,
+ the above case-insensitive sort is best written as::
+
+ >>> L.sort(key=str.lower)
+ >>> L
+ ['A', 'b', 'c', 'D']
+
+ Finally, the *reverse* parameter takes a Boolean value. If the value is true,
+ the list will be sorted into reverse order. Instead of ``L.sort() ;
+ L.reverse()``, you can now write ``L.sort(reverse=True)``.
+
+ The results of sorting are now guaranteed to be stable. This means that two
+ entries with equal keys will be returned in the same order as they were input.
+ For example, you can sort a list of people by name, and then sort the list by
+ age, resulting in a list sorted by age where people with the same age are in
+ name-sorted order.
+
+ (All changes to :meth:`sort` contributed by Raymond Hettinger.)
+
+* There is a new built-in function :func:`sorted(iterable)` that works like the
+ in-place :meth:`list.sort` method but can be used in expressions. The
+ differences are:
+
+* the input may be any iterable;
+
+* a newly formed copy is sorted, leaving the original intact; and
+
+* the expression returns the new sorted copy
+
+ ::
+
+ >>> L = [9,7,8,3,2,4,1,6,5]
+ >>> [10+i for i in sorted(L)] # usable in a list comprehension
+ [11, 12, 13, 14, 15, 16, 17, 18, 19]
+ >>> L # original is left unchanged
+ [9,7,8,3,2,4,1,6,5]
+ >>> sorted('Monty Python') # any iterable may be an input
+ [' ', 'M', 'P', 'h', 'n', 'n', 'o', 'o', 't', 't', 'y', 'y']
+
+ >>> # List the contents of a dict sorted by key values
+ >>> colormap = dict(red=1, blue=2, green=3, black=4, yellow=5)
+ >>> for k, v in sorted(colormap.iteritems()):
+ ... print k, v
+ ...
+ black 4
+ blue 2
+ green 3
+ red 1
+ yellow 5
+
+ (Contributed by Raymond Hettinger.)
+
+* Integer operations will no longer trigger an :exc:`OverflowWarning`. The
+ :exc:`OverflowWarning` warning will disappear in Python 2.5.
+
+* The interpreter gained a new switch, :option:`-m`, that takes a name, searches
+ for the corresponding module on ``sys.path``, and runs the module as a script.
+ For example, you can now run the Python profiler with ``python -m profile``.
+ (Contributed by Nick Coghlan.)
+
+* The :func:`eval(expr, globals, locals)` and :func:`execfile(filename, globals,
+ locals)` functions and the :keyword:`exec` statement now accept any mapping type
+ for the *locals* parameter. Previously this had to be a regular Python
+ dictionary. (Contributed by Raymond Hettinger.)
+
+* The :func:`zip` built-in function and :func:`itertools.izip` now return an
+ empty list if called with no arguments. Previously they raised a
+ :exc:`TypeError` exception. This makes them more suitable for use with variable
+ length argument lists::
+
+ >>> def transpose(array):
+ ... return zip(*array)
+ ...
+ >>> transpose([(1,2,3), (4,5,6)])
+ [(1, 4), (2, 5), (3, 6)]
+ >>> transpose([])
+ []
+
+ (Contributed by Raymond Hettinger.)
+
+* Encountering a failure while importing a module no longer leaves a partially-
+ initialized module object in ``sys.modules``. The incomplete module object left
+ behind would fool further imports of the same module into succeeding, leading to
+ confusing errors. (Fixed by Tim Peters.)
+
+* :const:`None` is now a constant; code that binds a new value to the name
+ ``None`` is now a syntax error. (Contributed by Raymond Hettinger.)
+
+.. % ======================================================================
+
+
+Optimizations
+-------------
+
+* The inner loops for list and tuple slicing were optimized and now run about
+ one-third faster. The inner loops for dictionaries were also optimized,
+ resulting in performance boosts for :meth:`keys`, :meth:`values`, :meth:`items`,
+ :meth:`iterkeys`, :meth:`itervalues`, and :meth:`iteritems`. (Contributed by
+ Raymond Hettinger.)
+
+* The machinery for growing and shrinking lists was optimized for speed and for
+ space efficiency. Appending and popping from lists now runs faster due to more
+ efficient code paths and less frequent use of the underlying system
+ :cfunc:`realloc`. List comprehensions also benefit. :meth:`list.extend` was
+ also optimized and no longer converts its argument into a temporary list before
+ extending the base list. (Contributed by Raymond Hettinger.)
+
+* :func:`list`, :func:`tuple`, :func:`map`, :func:`filter`, and :func:`zip` now
+ run several times faster with non-sequence arguments that supply a
+ :meth:`__len__` method. (Contributed by Raymond Hettinger.)
+
+* The methods :meth:`list.__getitem__`, :meth:`dict.__getitem__`, and
+ :meth:`dict.__contains__` are are now implemented as :class:`method_descriptor`
+ objects rather than :class:`wrapper_descriptor` objects. This form of access
+ doubles their performance and makes them more suitable for use as arguments to
+ functionals: ``map(mydict.__getitem__, keylist)``. (Contributed by Raymond
+ Hettinger.)
+
+* Added a new opcode, ``LIST_APPEND``, that simplifies the generated bytecode
+ for list comprehensions and speeds them up by about a third. (Contributed by
+ Raymond Hettinger.)
+
+* The peephole bytecode optimizer has been improved to produce shorter, faster
+ bytecode; remarkably, the resulting bytecode is more readable. (Enhanced by
+ Raymond Hettinger.)
+
+* String concatenations in statements of the form ``s = s + "abc"`` and ``s +=
+ "abc"`` are now performed more efficiently in certain circumstances. This
+ optimization won't be present in other Python implementations such as Jython, so
+ you shouldn't rely on it; using the :meth:`join` method of strings is still
+ recommended when you want to efficiently glue a large number of strings
+ together. (Contributed by Armin Rigo.)
+
+The net result of the 2.4 optimizations is that Python 2.4 runs the pystone
+benchmark around 5% faster than Python 2.3 and 35% faster than Python 2.2.
+(pystone is not a particularly good benchmark, but it's the most commonly used
+measurement of Python's performance. Your own applications may show greater or
+smaller benefits from Python 2.4.)
+
+.. % pystone is almost useless for comparing different versions of Python;
+.. % instead, it excels at predicting relative Python performance on
+.. % different machines.
+.. % So, this section would be more informative if it used other tools
+.. % such as pybench and parrotbench. For a more application oriented
+.. % benchmark, try comparing the timings of test_decimal.py under 2.3
+.. % and 2.4.
+
+.. % ======================================================================
+
+
+New, Improved, and Deprecated Modules
+=====================================
+
+As usual, Python's standard library received a number of enhancements and bug
+fixes. Here's a partial list of the most notable changes, sorted alphabetically
+by module name. Consult the :file:`Misc/NEWS` file in the source tree for a more
+complete list of changes, or look through the CVS logs for all the details.
+
+* The :mod:`asyncore` module's :func:`loop` function now has a *count* parameter
+ that lets you perform a limited number of passes through the polling loop. The
+ default is still to loop forever.
+
+* The :mod:`base64` module now has more complete RFC 3548 support for Base64,
+ Base32, and Base16 encoding and decoding, including optional case folding and
+ optional alternative alphabets. (Contributed by Barry Warsaw.)
+
+* The :mod:`bisect` module now has an underlying C implementation for improved
+ performance. (Contributed by Dmitry Vasiliev.)
+
+* The CJKCodecs collections of East Asian codecs, maintained by Hye-Shik Chang,
+ was integrated into 2.4. The new encodings are:
+
+* Chinese (PRC): gb2312, gbk, gb18030, big5hkscs, hz
+
+* Chinese (ROC): big5, cp950
+
+* Japanese: cp932, euc-jis-2004, euc-jp, euc-jisx0213, iso-2022-jp,
+ iso-2022-jp-1, iso-2022-jp-2, iso-2022-jp-3, iso-2022-jp-ext, iso-2022-jp-2004,
+ shift-jis, shift-jisx0213, shift-jis-2004
+
+* Korean: cp949, euc-kr, johab, iso-2022-kr
+
+* Some other new encodings were added: HP Roman8, ISO_8859-11, ISO_8859-16,
+ PCTP-154, and TIS-620.
+
+* The UTF-8 and UTF-16 codecs now cope better with receiving partial input.
+ Previously the :class:`StreamReader` class would try to read more data, making
+ it impossible to resume decoding from the stream. The :meth:`read` method will
+ now return as much data as it can and future calls will resume decoding where
+ previous ones left off. (Implemented by Walter Dörwald.)
+
+* There is a new :mod:`collections` module for various specialized collection
+ datatypes. Currently it contains just one type, :class:`deque`, a double-
+ ended queue that supports efficiently adding and removing elements from either
+ end::
+
+ >>> from collections import deque
+ >>> d = deque('ghi') # make a new deque with three items
+ >>> d.append('j') # add a new entry to the right side
+ >>> d.appendleft('f') # add a new entry to the left side
+ >>> d # show the representation of the deque
+ deque(['f', 'g', 'h', 'i', 'j'])
+ >>> d.pop() # return and remove the rightmost item
+ 'j'
+ >>> d.popleft() # return and remove the leftmost item
+ 'f'
+ >>> list(d) # list the contents of the deque
+ ['g', 'h', 'i']
+ >>> 'h' in d # search the deque
+ True
+
+ Several modules, such as the :mod:`Queue` and :mod:`threading` modules, now take
+ advantage of :class:`collections.deque` for improved performance. (Contributed
+ by Raymond Hettinger.)
+
+* The :mod:`ConfigParser` classes have been enhanced slightly. The :meth:`read`
+ method now returns a list of the files that were successfully parsed, and the
+ :meth:`set` method raises :exc:`TypeError` if passed a *value* argument that
+ isn't a string. (Contributed by John Belmonte and David Goodger.)
+
+* The :mod:`curses` module now supports the ncurses extension
+ :func:`use_default_colors`. On platforms where the terminal supports
+ transparency, this makes it possible to use a transparent background.
+ (Contributed by Jörg Lehmann.)
+
+* The :mod:`difflib` module now includes an :class:`HtmlDiff` class that creates
+ an HTML table showing a side by side comparison of two versions of a text.
+ (Contributed by Dan Gass.)
+
+* The :mod:`email` package was updated to version 3.0, which dropped various
+ deprecated APIs and removes support for Python versions earlier than 2.3. The
+ 3.0 version of the package uses a new incremental parser for MIME messages,
+ available in the :mod:`email.FeedParser` module. The new parser doesn't require
+ reading the entire message into memory, and doesn't throw exceptions if a
+ message is malformed; instead it records any problems in the :attr:`defect`
+ attribute of the message. (Developed by Anthony Baxter, Barry Warsaw, Thomas
+ Wouters, and others.)
+
+* The :mod:`heapq` module has been converted to C. The resulting tenfold
+ improvement in speed makes the module suitable for handling high volumes of
+ data. In addition, the module has two new functions :func:`nlargest` and
+ :func:`nsmallest` that use heaps to find the N largest or smallest values in a
+ dataset without the expense of a full sort. (Contributed by Raymond Hettinger.)
+
+* The :mod:`httplib` module now contains constants for HTTP status codes defined
+ in various HTTP-related RFC documents. Constants have names such as
+ :const:`OK`, :const:`CREATED`, :const:`CONTINUE`, and
+ :const:`MOVED_PERMANENTLY`; use pydoc to get a full list. (Contributed by
+ Andrew Eland.)
+
+* The :mod:`imaplib` module now supports IMAP's THREAD command (contributed by
+ Yves Dionne) and new :meth:`deleteacl` and :meth:`myrights` methods (contributed
+ by Arnaud Mazin).
+
+* The :mod:`itertools` module gained a :func:`groupby(iterable[, *func*])`
+ function. *iterable* is something that can be iterated over to return a stream
+ of elements, and the optional *func* parameter is a function that takes an
+ element and returns a key value; if omitted, the key is simply the element
+ itself. :func:`groupby` then groups the elements into subsequences which have
+ matching values of the key, and returns a series of 2-tuples containing the key
+ value and an iterator over the subsequence.
+
+ Here's an example to make this clearer. The *key* function simply returns
+ whether a number is even or odd, so the result of :func:`groupby` is to return
+ consecutive runs of odd or even numbers. ::
+
+ >>> import itertools
+ >>> L = [2, 4, 6, 7, 8, 9, 11, 12, 14]
+ >>> for key_val, it in itertools.groupby(L, lambda x: x % 2):
+ ... print key_val, list(it)
+ ...
+ 0 [2, 4, 6]
+ 1 [7]
+ 0 [8]
+ 1 [9, 11]
+ 0 [12, 14]
+ >>>
+
+ :func:`groupby` is typically used with sorted input. The logic for
+ :func:`groupby` is similar to the Unix ``uniq`` filter which makes it handy for
+ eliminating, counting, or identifying duplicate elements::
+
+ >>> word = 'abracadabra'
+ >>> letters = sorted(word) # Turn string into a sorted list of letters
+ >>> letters
+ ['a', 'a', 'a', 'a', 'a', 'b', 'b', 'c', 'd', 'r', 'r']
+ >>> for k, g in itertools.groupby(letters):
+ ... print k, list(g)
+ ...
+ a ['a', 'a', 'a', 'a', 'a']
+ b ['b', 'b']
+ c ['c']
+ d ['d']
+ r ['r', 'r']
+ >>> # List unique letters
+ >>> [k for k, g in groupby(letters)]
+ ['a', 'b', 'c', 'd', 'r']
+ >>> # Count letter occurrences
+ >>> [(k, len(list(g))) for k, g in groupby(letters)]
+ [('a', 5), ('b', 2), ('c', 1), ('d', 1), ('r', 2)]
+
+ (Contributed by Hye-Shik Chang.)
+
+* :mod:`itertools` also gained a function named :func:`tee(iterator, N)` that
+ returns *N* independent iterators that replicate *iterator*. If *N* is omitted,
+ the default is 2. ::
+
+ >>> L = [1,2,3]
+ >>> i1, i2 = itertools.tee(L)
+ >>> i1,i2
+ (<itertools.tee object at 0x402c2080>, <itertools.tee object at 0x402c2090>)
+ >>> list(i1) # Run the first iterator to exhaustion
+ [1, 2, 3]
+ >>> list(i2) # Run the second iterator to exhaustion
+ [1, 2, 3]
+
+ Note that :func:`tee` has to keep copies of the values returned by the
+ iterator; in the worst case, it may need to keep all of them. This should
+ therefore be used carefully if the leading iterator can run far ahead of the
+ trailing iterator in a long stream of inputs. If the separation is large, then
+ you might as well use :func:`list` instead. When the iterators track closely
+ with one another, :func:`tee` is ideal. Possible applications include
+ bookmarking, windowing, or lookahead iterators. (Contributed by Raymond
+ Hettinger.)
+
+* A number of functions were added to the :mod:`locale` module, such as
+ :func:`bind_textdomain_codeset` to specify a particular encoding and a family of
+ :func:`l\*gettext` functions that return messages in the chosen encoding.
+ (Contributed by Gustavo Niemeyer.)
+
+* Some keyword arguments were added to the :mod:`logging` package's
+ :func:`basicConfig` function to simplify log configuration. The default
+ behavior is to log messages to standard error, but various keyword arguments can
+ be specified to log to a particular file, change the logging format, or set the
+ logging level. For example::
+
+ import logging
+ logging.basicConfig(filename='/var/log/application.log',
+ level=0, # Log all messages
+ format='%(levelname):%(process):%(thread):%(message)')
+
+ Other additions to the :mod:`logging` package include a :meth:`log(level, msg)`
+ convenience method, as well as a :class:`TimedRotatingFileHandler` class that
+ rotates its log files at a timed interval. The module already had
+ :class:`RotatingFileHandler`, which rotated logs once the file exceeded a
+ certain size. Both classes derive from a new :class:`BaseRotatingHandler` class
+ that can be used to implement other rotating handlers.
+
+ (Changes implemented by Vinay Sajip.)
+
+* The :mod:`marshal` module now shares interned strings on unpacking a data
+ structure. This may shrink the size of certain pickle strings, but the primary
+ effect is to make :file:`.pyc` files significantly smaller. (Contributed by
+ Martin von Löwis.)
+
+* The :mod:`nntplib` module's :class:`NNTP` class gained :meth:`description` and
+ :meth:`descriptions` methods to retrieve newsgroup descriptions for a single
+ group or for a range of groups. (Contributed by Jürgen A. Erhard.)
+
+* Two new functions were added to the :mod:`operator` module,
+ :func:`attrgetter(attr)` and :func:`itemgetter(index)`. Both functions return
+ callables that take a single argument and return the corresponding attribute or
+ item; these callables make excellent data extractors when used with :func:`map`
+ or :func:`sorted`. For example::
+
+ >>> L = [('c', 2), ('d', 1), ('a', 4), ('b', 3)]
+ >>> map(operator.itemgetter(0), L)
+ ['c', 'd', 'a', 'b']
+ >>> map(operator.itemgetter(1), L)
+ [2, 1, 4, 3]
+ >>> sorted(L, key=operator.itemgetter(1)) # Sort list by second tuple item
+ [('d', 1), ('c', 2), ('b', 3), ('a', 4)]
+
+ (Contributed by Raymond Hettinger.)
+
+* The :mod:`optparse` module was updated in various ways. The module now passes
+ its messages through :func:`gettext.gettext`, making it possible to
+ internationalize Optik's help and error messages. Help messages for options can
+ now include the string ``'%default'``, which will be replaced by the option's
+ default value. (Contributed by Greg Ward.)
+
+* The long-term plan is to deprecate the :mod:`rfc822` module in some future
+ Python release in favor of the :mod:`email` package. To this end, the
+ :func:`email.Utils.formatdate` function has been changed to make it usable as a
+ replacement for :func:`rfc822.formatdate`. You may want to write new e-mail
+ processing code with this in mind. (Change implemented by Anthony Baxter.)
+
+* A new :func:`urandom(n)` function was added to the :mod:`os` module, returning
+ a string containing *n* bytes of random data. This function provides access to
+ platform-specific sources of randomness such as :file:`/dev/urandom` on Linux or
+ the Windows CryptoAPI. (Contributed by Trevor Perrin.)
+
+* Another new function: :func:`os.path.lexists(path)` returns true if the file
+ specified by *path* exists, whether or not it's a symbolic link. This differs
+ from the existing :func:`os.path.exists(path)` function, which returns false if
+ *path* is a symlink that points to a destination that doesn't exist.
+ (Contributed by Beni Cherniavsky.)
+
+* A new :func:`getsid` function was added to the :mod:`posix` module that
+ underlies the :mod:`os` module. (Contributed by J. Raynor.)
+
+* The :mod:`poplib` module now supports POP over SSL. (Contributed by Hector
+ Urtubia.)
+
+* The :mod:`profile` module can now profile C extension functions. (Contributed
+ by Nick Bastin.)
+
+* The :mod:`random` module has a new method called :meth:`getrandbits(N)` that
+ returns a long integer *N* bits in length. The existing :meth:`randrange`
+ method now uses :meth:`getrandbits` where appropriate, making generation of
+ arbitrarily large random numbers more efficient. (Contributed by Raymond
+ Hettinger.)
+
+* The regular expression language accepted by the :mod:`re` module was extended
+ with simple conditional expressions, written as ``(?(group)A|B)``. *group* is
+ either a numeric group ID or a group name defined with ``(?P<group>...)``
+ earlier in the expression. If the specified group matched, the regular
+ expression pattern *A* will be tested against the string; if the group didn't
+ match, the pattern *B* will be used instead. (Contributed by Gustavo Niemeyer.)
+
+* The :mod:`re` module is also no longer recursive, thanks to a massive amount
+ of work by Gustavo Niemeyer. In a recursive regular expression engine, certain
+ patterns result in a large amount of C stack space being consumed, and it was
+ possible to overflow the stack. For example, if you matched a 30000-byte string
+ of ``a`` characters against the expression ``(a|b)+``, one stack frame was
+ consumed per character. Python 2.3 tried to check for stack overflow and raise
+ a :exc:`RuntimeError` exception, but certain patterns could sidestep the
+ checking and if you were unlucky Python could segfault. Python 2.4's regular
+ expression engine can match this pattern without problems.
+
+* The :mod:`signal` module now performs tighter error-checking on the parameters
+ to the :func:`signal.signal` function. For example, you can't set a handler on
+ the :const:`SIGKILL` signal; previous versions of Python would quietly accept
+ this, but 2.4 will raise a :exc:`RuntimeError` exception.
+
+* Two new functions were added to the :mod:`socket` module. :func:`socketpair`
+ returns a pair of connected sockets and :func:`getservbyport(port)` looks up the
+ service name for a given port number. (Contributed by Dave Cole and Barry
+ Warsaw.)
+
+* The :func:`sys.exitfunc` function has been deprecated. Code should be using
+ the existing :mod:`atexit` module, which correctly handles calling multiple exit
+ functions. Eventually :func:`sys.exitfunc` will become a purely internal
+ interface, accessed only by :mod:`atexit`.
+
+* The :mod:`tarfile` module now generates GNU-format tar files by default.
+ (Contributed by Lars Gustaebel.)
+
+* The :mod:`threading` module now has an elegantly simple way to support
+ thread-local data. The module contains a :class:`local` class whose attribute
+ values are local to different threads. ::
+
+ import threading
+
+ data = threading.local()
+ data.number = 42
+ data.url = ('www.python.org', 80)
+
+ Other threads can assign and retrieve their own values for the :attr:`number`
+ and :attr:`url` attributes. You can subclass :class:`local` to initialize
+ attributes or to add methods. (Contributed by Jim Fulton.)
+
+* The :mod:`timeit` module now automatically disables periodic garbage
+ collection during the timing loop. This change makes consecutive timings more
+ comparable. (Contributed by Raymond Hettinger.)
+
+* The :mod:`weakref` module now supports a wider variety of objects including
+ Python functions, class instances, sets, frozensets, deques, arrays, files,
+ sockets, and regular expression pattern objects. (Contributed by Raymond
+ Hettinger.)
+
+* The :mod:`xmlrpclib` module now supports a multi-call extension for
+ transmitting multiple XML-RPC calls in a single HTTP operation. (Contributed by
+ Brian Quinlan.)
+
+* The :mod:`mpz`, :mod:`rotor`, and :mod:`xreadlines` modules have been
+ removed.
+
+.. % ======================================================================
+.. % whole new modules get described in subsections here
+.. % =====================
+
+
+cookielib
+---------
+
+The :mod:`cookielib` library supports client-side handling for HTTP cookies,
+mirroring the :mod:`Cookie` module's server-side cookie support. Cookies are
+stored in cookie jars; the library transparently stores cookies offered by the
+web server in the cookie jar, and fetches the cookie from the jar when
+connecting to the server. As in web browsers, policy objects control whether
+cookies are accepted or not.
+
+In order to store cookies across sessions, two implementations of cookie jars
+are provided: one that stores cookies in the Netscape format so applications can
+use the Mozilla or Lynx cookie files, and one that stores cookies in the same
+format as the Perl libwww library.
+
+:mod:`urllib2` has been changed to interact with :mod:`cookielib`:
+:class:`HTTPCookieProcessor` manages a cookie jar that is used when accessing
+URLs.
+
+This module was contributed by John J. Lee.
+
+.. % ==================
+
+
+doctest
+-------
+
+The :mod:`doctest` module underwent considerable refactoring thanks to Edward
+Loper and Tim Peters. Testing can still be as simple as running
+:func:`doctest.testmod`, but the refactorings allow customizing the module's
+operation in various ways
+
+The new :class:`DocTestFinder` class extracts the tests from a given object's
+docstrings::
+
+ def f (x, y):
+ """>>> f(2,2)
+ 4
+ >>> f(3,2)
+ 6
+ """
+ return x*y
+
+ finder = doctest.DocTestFinder()
+
+ # Get list of DocTest instances
+ tests = finder.find(f)
+
+The new :class:`DocTestRunner` class then runs individual tests and can produce
+a summary of the results::
+
+ runner = doctest.DocTestRunner()
+ for t in tests:
+ tried, failed = runner.run(t)
+
+ runner.summarize(verbose=1)
+
+The above example produces the following output::
+
+ 1 items passed all tests:
+ 2 tests in f
+ 2 tests in 1 items.
+ 2 passed and 0 failed.
+ Test passed.
+
+:class:`DocTestRunner` uses an instance of the :class:`OutputChecker` class to
+compare the expected output with the actual output. This class takes a number
+of different flags that customize its behaviour; ambitious users can also write
+a completely new subclass of :class:`OutputChecker`.
+
+The default output checker provides a number of handy features. For example,
+with the :const:`doctest.ELLIPSIS` option flag, an ellipsis (``...``) in the
+expected output matches any substring, making it easier to accommodate outputs
+that vary in minor ways::
+
+ def o (n):
+ """>>> o(1)
+ <__main__.C instance at 0x...>
+ >>>
+ """
+
+Another special string, ``<BLANKLINE>``, matches a blank line::
+
+ def p (n):
+ """>>> p(1)
+ <BLANKLINE>
+ >>>
+ """
+
+Another new capability is producing a diff-style display of the output by
+specifying the :const:`doctest.REPORT_UDIFF` (unified diffs),
+:const:`doctest.REPORT_CDIFF` (context diffs), or :const:`doctest.REPORT_NDIFF`
+(delta-style) option flags. For example::
+
+ def g (n):
+ """>>> g(4)
+ here
+ is
+ a
+ lengthy
+ >>>"""
+ L = 'here is a rather lengthy list of words'.split()
+ for word in L[:n]:
+ print word
+
+Running the above function's tests with :const:`doctest.REPORT_UDIFF` specified,
+you get the following output::
+
+ **********************************************************************
+ File ``t.py'', line 15, in g
+ Failed example:
+ g(4)
+ Differences (unified diff with -expected +actual):
+ @@ -2,3 +2,3 @@
+ is
+ a
+ -lengthy
+ +rather
+ **********************************************************************
+
+.. % ======================================================================
+
+
+Build and C API Changes
+=======================
+
+Some of the changes to Python's build process and to the C API are:
+
+* Three new convenience macros were added for common return values from
+ extension functions: :cmacro:`Py_RETURN_NONE`, :cmacro:`Py_RETURN_TRUE`, and
+ :cmacro:`Py_RETURN_FALSE`. (Contributed by Brett Cannon.)
+
+* Another new macro, :cmacro:`Py_CLEAR(obj)`, decreases the reference count of
+ *obj* and sets *obj* to the null pointer. (Contributed by Jim Fulton.)
+
+* A new function, :cfunc:`PyTuple_Pack(N, obj1, obj2, ..., objN)`, constructs
+ tuples from a variable length argument list of Python objects. (Contributed by
+ Raymond Hettinger.)
+
+* A new function, :cfunc:`PyDict_Contains(d, k)`, implements fast dictionary
+ lookups without masking exceptions raised during the look-up process.
+ (Contributed by Raymond Hettinger.)
+
+* The :cmacro:`Py_IS_NAN(X)` macro returns 1 if its float or double argument
+ *X* is a NaN. (Contributed by Tim Peters.)
+
+* C code can avoid unnecessary locking by using the new
+ :cfunc:`PyEval_ThreadsInitialized` function to tell if any thread operations
+ have been performed. If this function returns false, no lock operations are
+ needed. (Contributed by Nick Coghlan.)
+
+* A new function, :cfunc:`PyArg_VaParseTupleAndKeywords`, is the same as
+ :cfunc:`PyArg_ParseTupleAndKeywords` but takes a :ctype:`va_list` instead of a
+ number of arguments. (Contributed by Greg Chapman.)
+
+* A new method flag, :const:`METH_COEXISTS`, allows a function defined in slots
+ to co-exist with a :ctype:`PyCFunction` having the same name. This can halve
+ the access time for a method such as :meth:`set.__contains__`. (Contributed by
+ Raymond Hettinger.)
+
+* Python can now be built with additional profiling for the interpreter itself,
+ intended as an aid to people developing the Python core. Providing
+ :option:`----enable-profiling` to the :program:`configure` script will let you
+ profile the interpreter with :program:`gprof`, and providing the
+ :option:`----with-tsc` switch enables profiling using the Pentium's Time-Stamp-
+ Counter register. Note that the :option:`----with-tsc` switch is slightly
+ misnamed, because the profiling feature also works on the PowerPC platform,
+ though that processor architecture doesn't call that register "the TSC
+ register". (Contributed by Jeremy Hylton.)
+
+* The :ctype:`tracebackobject` type has been renamed to
+ :ctype:`PyTracebackObject`.
+
+.. % ======================================================================
+
+
+Port-Specific Changes
+---------------------
+
+* The Windows port now builds under MSVC++ 7.1 as well as version 6.
+ (Contributed by Martin von Löwis.)
+
+.. % ======================================================================
+
+
+Porting to Python 2.4
+=====================
+
+This section lists previously described changes that may require changes to your
+code:
+
+* Left shifts and hexadecimal/octal constants that are too large no longer
+ trigger a :exc:`FutureWarning` and return a value limited to 32 or 64 bits;
+ instead they return a long integer.
+
+* Integer operations will no longer trigger an :exc:`OverflowWarning`. The
+ :exc:`OverflowWarning` warning will disappear in Python 2.5.
+
+* The :func:`zip` built-in function and :func:`itertools.izip` now return an
+ empty list instead of raising a :exc:`TypeError` exception if called with no
+ arguments.
+
+* You can no longer compare the :class:`date` and :class:`datetime` instances
+ provided by the :mod:`datetime` module. Two instances of different classes
+ will now always be unequal, and relative comparisons (``<``, ``>``) will raise
+ a :exc:`TypeError`.
+
+* :func:`dircache.listdir` now passes exceptions to the caller instead of
+ returning empty lists.
+
+* :func:`LexicalHandler.startDTD` used to receive the public and system IDs in
+ the wrong order. This has been corrected; applications relying on the wrong
+ order need to be fixed.
+
+* :func:`fcntl.ioctl` now warns if the *mutate* argument is omitted and
+ relevant.
+
+* The :mod:`tarfile` module now generates GNU-format tar files by default.
+
+* Encountering a failure while importing a module no longer leaves a partially-
+ initialized module object in ``sys.modules``.
+
+* :const:`None` is now a constant; code that binds a new value to the name
+ ``None`` is now a syntax error.
+
+* The :func:`signals.signal` function now raises a :exc:`RuntimeError` exception
+ for certain illegal values; previously these errors would pass silently. For
+ example, you can no longer set a handler on the :const:`SIGKILL` signal.
+
+.. % ======================================================================
+
+
+.. _acks:
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: Koray Can, Hye-
+Shik Chang, Michael Dyck, Raymond Hettinger, Brian Hurt, Hamish Lawson, Fredrik
+Lundh, Sean Reifschneider, Sadruddin Rejeb.
+
diff --git a/Doc/whatsnew/2.5.rst b/Doc/whatsnew/2.5.rst
new file mode 100644
index 0000000000..f0429ecf84
--- /dev/null
+++ b/Doc/whatsnew/2.5.rst
@@ -0,0 +1,2286 @@
+****************************
+ What's New in Python 2.5
+****************************
+
+:Author: A.M. Kuchling
+
+.. |release| replace:: 1.01
+
+.. % $Id: whatsnew25.tex 56611 2007-07-29 08:26:10Z georg.brandl $
+.. % Fix XXX comments
+
+This article explains the new features in Python 2.5. The final release of
+Python 2.5 is scheduled for August 2006; :pep:`356` describes the planned
+release schedule.
+
+The changes in Python 2.5 are an interesting mix of language and library
+improvements. The library enhancements will be more important to Python's user
+community, I think, because several widely-useful packages were added. New
+modules include ElementTree for XML processing (section :ref:`module-etree`),
+the SQLite database module (section :ref:`module-sqlite`), and the :mod:`ctypes`
+module for calling C functions (section :ref:`module-ctypes`).
+
+The language changes are of middling significance. Some pleasant new features
+were added, but most of them aren't features that you'll use every day.
+Conditional expressions were finally added to the language using a novel syntax;
+see section :ref:`pep-308`. The new ':keyword:`with`' statement will make
+writing cleanup code easier (section :ref:`pep-343`). Values can now be passed
+into generators (section :ref:`pep-342`). Imports are now visible as either
+absolute or relative (section :ref:`pep-328`). Some corner cases of exception
+handling are handled better (section :ref:`pep-341`). All these improvements
+are worthwhile, but they're improvements to one specific language feature or
+another; none of them are broad modifications to Python's semantics.
+
+As well as the language and library additions, other improvements and bugfixes
+were made throughout the source tree. A search through the SVN change logs
+finds there were 353 patches applied and 458 bugs fixed between Python 2.4 and
+2.5. (Both figures are likely to be underestimates.)
+
+This article doesn't try to be a complete specification of the new features;
+instead changes are briefly introduced using helpful examples. For full
+details, you should always refer to the documentation for Python 2.5 at
+http://docs.python.org. If you want to understand the complete implementation
+and design rationale, refer to the PEP for a particular new feature.
+
+Comments, suggestions, and error reports for this document are welcome; please
+e-mail them to the author or open a bug in the Python bug tracker.
+
+.. % ======================================================================
+
+
+.. _pep-308:
+
+PEP 308: Conditional Expressions
+================================
+
+For a long time, people have been requesting a way to write conditional
+expressions, which are expressions that return value A or value B depending on
+whether a Boolean value is true or false. A conditional expression lets you
+write a single assignment statement that has the same effect as the following::
+
+ if condition:
+ x = true_value
+ else:
+ x = false_value
+
+There have been endless tedious discussions of syntax on both python-dev and
+comp.lang.python. A vote was even held that found the majority of voters wanted
+conditional expressions in some form, but there was no syntax that was preferred
+by a clear majority. Candidates included C's ``cond ? true_v : false_v``, ``if
+cond then true_v else false_v``, and 16 other variations.
+
+Guido van Rossum eventually chose a surprising syntax::
+
+ x = true_value if condition else false_value
+
+Evaluation is still lazy as in existing Boolean expressions, so the order of
+evaluation jumps around a bit. The *condition* expression in the middle is
+evaluated first, and the *true_value* expression is evaluated only if the
+condition was true. Similarly, the *false_value* expression is only evaluated
+when the condition is false.
+
+This syntax may seem strange and backwards; why does the condition go in the
+*middle* of the expression, and not in the front as in C's ``c ? x : y``? The
+decision was checked by applying the new syntax to the modules in the standard
+library and seeing how the resulting code read. In many cases where a
+conditional expression is used, one value seems to be the 'common case' and one
+value is an 'exceptional case', used only on rarer occasions when the condition
+isn't met. The conditional syntax makes this pattern a bit more obvious::
+
+ contents = ((doc + '\n') if doc else '')
+
+I read the above statement as meaning "here *contents* is usually assigned a
+value of ``doc+'\n'``; sometimes *doc* is empty, in which special case an empty
+string is returned." I doubt I will use conditional expressions very often
+where there isn't a clear common and uncommon case.
+
+There was some discussion of whether the language should require surrounding
+conditional expressions with parentheses. The decision was made to *not*
+require parentheses in the Python language's grammar, but as a matter of style I
+think you should always use them. Consider these two statements::
+
+ # First version -- no parens
+ level = 1 if logging else 0
+
+ # Second version -- with parens
+ level = (1 if logging else 0)
+
+In the first version, I think a reader's eye might group the statement into
+'level = 1', 'if logging', 'else 0', and think that the condition decides
+whether the assignment to *level* is performed. The second version reads
+better, in my opinion, because it makes it clear that the assignment is always
+performed and the choice is being made between two values.
+
+Another reason for including the brackets: a few odd combinations of list
+comprehensions and lambdas could look like incorrect conditional expressions.
+See :pep:`308` for some examples. If you put parentheses around your
+conditional expressions, you won't run into this case.
+
+
+.. seealso::
+
+ :pep:`308` - Conditional Expressions
+ PEP written by Guido van Rossum and Raymond D. Hettinger; implemented by Thomas
+ Wouters.
+
+.. % ======================================================================
+
+
+.. _pep-309:
+
+PEP 309: Partial Function Application
+=====================================
+
+The :mod:`functools` module is intended to contain tools for functional-style
+programming.
+
+One useful tool in this module is the :func:`partial` function. For programs
+written in a functional style, you'll sometimes want to construct variants of
+existing functions that have some of the parameters filled in. Consider a
+Python function ``f(a, b, c)``; you could create a new function ``g(b, c)`` that
+was equivalent to ``f(1, b, c)``. This is called "partial function
+application".
+
+:func:`partial` takes the arguments ``(function, arg1, arg2, ... kwarg1=value1,
+kwarg2=value2)``. The resulting object is callable, so you can just call it to
+invoke *function* with the filled-in arguments.
+
+Here's a small but realistic example::
+
+ import functools
+
+ def log (message, subsystem):
+ "Write the contents of 'message' to the specified subsystem."
+ print '%s: %s' % (subsystem, message)
+ ...
+
+ server_log = functools.partial(log, subsystem='server')
+ server_log('Unable to open socket')
+
+Here's another example, from a program that uses PyGTK. Here a context-
+sensitive pop-up menu is being constructed dynamically. The callback provided
+for the menu option is a partially applied version of the :meth:`open_item`
+method, where the first argument has been provided. ::
+
+ ...
+ class Application:
+ def open_item(self, path):
+ ...
+ def init (self):
+ open_func = functools.partial(self.open_item, item_path)
+ popup_menu.append( ("Open", open_func, 1) )
+
+Another function in the :mod:`functools` module is the
+:func:`update_wrapper(wrapper, wrapped)` function that helps you write well-
+behaved decorators. :func:`update_wrapper` copies the name, module, and
+docstring attribute to a wrapper function so that tracebacks inside the wrapped
+function are easier to understand. For example, you might write::
+
+ def my_decorator(f):
+ def wrapper(*args, **kwds):
+ print 'Calling decorated function'
+ return f(*args, **kwds)
+ functools.update_wrapper(wrapper, f)
+ return wrapper
+
+:func:`wraps` is a decorator that can be used inside your own decorators to copy
+the wrapped function's information. An alternate version of the previous
+example would be::
+
+ def my_decorator(f):
+ @functools.wraps(f)
+ def wrapper(*args, **kwds):
+ print 'Calling decorated function'
+ return f(*args, **kwds)
+ return wrapper
+
+
+.. seealso::
+
+ :pep:`309` - Partial Function Application
+ PEP proposed and written by Peter Harris; implemented by Hye-Shik Chang and Nick
+ Coghlan, with adaptations by Raymond Hettinger.
+
+.. % ======================================================================
+
+
+.. _pep-314:
+
+PEP 314: Metadata for Python Software Packages v1.1
+===================================================
+
+Some simple dependency support was added to Distutils. The :func:`setup`
+function now has ``requires``, ``provides``, and ``obsoletes`` keyword
+parameters. When you build a source distribution using the ``sdist`` command,
+the dependency information will be recorded in the :file:`PKG-INFO` file.
+
+Another new keyword parameter is ``download_url``, which should be set to a URL
+for the package's source code. This means it's now possible to look up an entry
+in the package index, determine the dependencies for a package, and download the
+required packages. ::
+
+ VERSION = '1.0'
+ setup(name='PyPackage',
+ version=VERSION,
+ requires=['numarray', 'zlib (>=1.1.4)'],
+ obsoletes=['OldPackage']
+ download_url=('http://www.example.com/pypackage/dist/pkg-%s.tar.gz'
+ % VERSION),
+ )
+
+Another new enhancement to the Python package index at
+http://cheeseshop.python.org is storing source and binary archives for a
+package. The new :command:`upload` Distutils command will upload a package to
+the repository.
+
+Before a package can be uploaded, you must be able to build a distribution using
+the :command:`sdist` Distutils command. Once that works, you can run ``python
+setup.py upload`` to add your package to the PyPI archive. Optionally you can
+GPG-sign the package by supplying the :option:`--sign` and :option:`--identity`
+options.
+
+Package uploading was implemented by Martin von Löwis and Richard Jones.
+
+
+.. seealso::
+
+ :pep:`314` - Metadata for Python Software Packages v1.1
+ PEP proposed and written by A.M. Kuchling, Richard Jones, and Fred Drake;
+ implemented by Richard Jones and Fred Drake.
+
+.. % ======================================================================
+
+
+.. _pep-328:
+
+PEP 328: Absolute and Relative Imports
+======================================
+
+The simpler part of PEP 328 was implemented in Python 2.4: parentheses could now
+be used to enclose the names imported from a module using the ``from ... import
+...`` statement, making it easier to import many different names.
+
+The more complicated part has been implemented in Python 2.5: importing a module
+can be specified to use absolute or package-relative imports. The plan is to
+move toward making absolute imports the default in future versions of Python.
+
+Let's say you have a package directory like this::
+
+ pkg/
+ pkg/__init__.py
+ pkg/main.py
+ pkg/string.py
+
+This defines a package named :mod:`pkg` containing the :mod:`pkg.main` and
+:mod:`pkg.string` submodules.
+
+Consider the code in the :file:`main.py` module. What happens if it executes
+the statement ``import string``? In Python 2.4 and earlier, it will first look
+in the package's directory to perform a relative import, finds
+:file:`pkg/string.py`, imports the contents of that file as the
+:mod:`pkg.string` module, and that module is bound to the name ``string`` in the
+:mod:`pkg.main` module's namespace.
+
+That's fine if :mod:`pkg.string` was what you wanted. But what if you wanted
+Python's standard :mod:`string` module? There's no clean way to ignore
+:mod:`pkg.string` and look for the standard module; generally you had to look at
+the contents of ``sys.modules``, which is slightly unclean. Holger Krekel's
+:mod:`py.std` package provides a tidier way to perform imports from the standard
+library, ``import py ; py.std.string.join()``, but that package isn't available
+on all Python installations.
+
+Reading code which relies on relative imports is also less clear, because a
+reader may be confused about which module, :mod:`string` or :mod:`pkg.string`,
+is intended to be used. Python users soon learned not to duplicate the names of
+standard library modules in the names of their packages' submodules, but you
+can't protect against having your submodule's name being used for a new module
+added in a future version of Python.
+
+In Python 2.5, you can switch :keyword:`import`'s behaviour to absolute imports
+using a ``from __future__ import absolute_import`` directive. This absolute-
+import behaviour will become the default in a future version (probably Python
+2.7). Once absolute imports are the default, ``import string`` will always
+find the standard library's version. It's suggested that users should begin
+using absolute imports as much as possible, so it's preferable to begin writing
+``from pkg import string`` in your code.
+
+Relative imports are still possible by adding a leading period to the module
+name when using the ``from ... import`` form::
+
+ # Import names from pkg.string
+ from .string import name1, name2
+ # Import pkg.string
+ from . import string
+
+This imports the :mod:`string` module relative to the current package, so in
+:mod:`pkg.main` this will import *name1* and *name2* from :mod:`pkg.string`.
+Additional leading periods perform the relative import starting from the parent
+of the current package. For example, code in the :mod:`A.B.C` module can do::
+
+ from . import D # Imports A.B.D
+ from .. import E # Imports A.E
+ from ..F import G # Imports A.F.G
+
+Leading periods cannot be used with the ``import modname`` form of the import
+statement, only the ``from ... import`` form.
+
+
+.. seealso::
+
+ :pep:`328` - Imports: Multi-Line and Absolute/Relative
+ PEP written by Aahz; implemented by Thomas Wouters.
+
+ http://codespeak.net/py/current/doc/index.html
+ The py library by Holger Krekel, which contains the :mod:`py.std` package.
+
+.. % ======================================================================
+
+
+.. _pep-338:
+
+PEP 338: Executing Modules as Scripts
+=====================================
+
+The :option:`-m` switch added in Python 2.4 to execute a module as a script
+gained a few more abilities. Instead of being implemented in C code inside the
+Python interpreter, the switch now uses an implementation in a new module,
+:mod:`runpy`.
+
+The :mod:`runpy` module implements a more sophisticated import mechanism so that
+it's now possible to run modules in a package such as :mod:`pychecker.checker`.
+The module also supports alternative import mechanisms such as the
+:mod:`zipimport` module. This means you can add a .zip archive's path to
+``sys.path`` and then use the :option:`-m` switch to execute code from the
+archive.
+
+
+.. seealso::
+
+ :pep:`338` - Executing modules as scripts
+ PEP written and implemented by Nick Coghlan.
+
+.. % ======================================================================
+
+
+.. _pep-341:
+
+PEP 341: Unified try/except/finally
+===================================
+
+Until Python 2.5, the :keyword:`try` statement came in two flavours. You could
+use a :keyword:`finally` block to ensure that code is always executed, or one or
+more :keyword:`except` blocks to catch specific exceptions. You couldn't
+combine both :keyword:`except` blocks and a :keyword:`finally` block, because
+generating the right bytecode for the combined version was complicated and it
+wasn't clear what the semantics of the combined statement should be.
+
+Guido van Rossum spent some time working with Java, which does support the
+equivalent of combining :keyword:`except` blocks and a :keyword:`finally` block,
+and this clarified what the statement should mean. In Python 2.5, you can now
+write::
+
+ try:
+ block-1 ...
+ except Exception1:
+ handler-1 ...
+ except Exception2:
+ handler-2 ...
+ else:
+ else-block
+ finally:
+ final-block
+
+The code in *block-1* is executed. If the code raises an exception, the various
+:keyword:`except` blocks are tested: if the exception is of class
+:class:`Exception1`, *handler-1* is executed; otherwise if it's of class
+:class:`Exception2`, *handler-2* is executed, and so forth. If no exception is
+raised, the *else-block* is executed.
+
+No matter what happened previously, the *final-block* is executed once the code
+block is complete and any raised exceptions handled. Even if there's an error in
+an exception handler or the *else-block* and a new exception is raised, the code
+in the *final-block* is still run.
+
+
+.. seealso::
+
+ :pep:`341` - Unifying try-except and try-finally
+ PEP written by Georg Brandl; implementation by Thomas Lee.
+
+.. % ======================================================================
+
+
+.. _pep-342:
+
+PEP 342: New Generator Features
+===============================
+
+Python 2.5 adds a simple way to pass values *into* a generator. As introduced in
+Python 2.3, generators only produce output; once a generator's code was invoked
+to create an iterator, there was no way to pass any new information into the
+function when its execution is resumed. Sometimes the ability to pass in some
+information would be useful. Hackish solutions to this include making the
+generator's code look at a global variable and then changing the global
+variable's value, or passing in some mutable object that callers then modify.
+
+To refresh your memory of basic generators, here's a simple example::
+
+ def counter (maximum):
+ i = 0
+ while i < maximum:
+ yield i
+ i += 1
+
+When you call ``counter(10)``, the result is an iterator that returns the values
+from 0 up to 9. On encountering the :keyword:`yield` statement, the iterator
+returns the provided value and suspends the function's execution, preserving the
+local variables. Execution resumes on the following call to the iterator's
+:meth:`next` method, picking up after the :keyword:`yield` statement.
+
+In Python 2.3, :keyword:`yield` was a statement; it didn't return any value. In
+2.5, :keyword:`yield` is now an expression, returning a value that can be
+assigned to a variable or otherwise operated on::
+
+ val = (yield i)
+
+I recommend that you always put parentheses around a :keyword:`yield` expression
+when you're doing something with the returned value, as in the above example.
+The parentheses aren't always necessary, but it's easier to always add them
+instead of having to remember when they're needed.
+
+(:pep:`342` explains the exact rules, which are that a :keyword:`yield`\
+-expression must always be parenthesized except when it occurs at the top-level
+expression on the right-hand side of an assignment. This means you can write
+``val = yield i`` but have to use parentheses when there's an operation, as in
+``val = (yield i) + 12``.)
+
+Values are sent into a generator by calling its :meth:`send(value)` method. The
+generator's code is then resumed and the :keyword:`yield` expression returns the
+specified *value*. If the regular :meth:`next` method is called, the
+:keyword:`yield` returns :const:`None`.
+
+Here's the previous example, modified to allow changing the value of the
+internal counter. ::
+
+ def counter (maximum):
+ i = 0
+ while i < maximum:
+ val = (yield i)
+ # If value provided, change counter
+ if val is not None:
+ i = val
+ else:
+ i += 1
+
+And here's an example of changing the counter::
+
+ >>> it = counter(10)
+ >>> print it.next()
+ 0
+ >>> print it.next()
+ 1
+ >>> print it.send(8)
+ 8
+ >>> print it.next()
+ 9
+ >>> print it.next()
+ Traceback (most recent call last):
+ File ``t.py'', line 15, in ?
+ print it.next()
+ StopIteration
+
+:keyword:`yield` will usually return :const:`None`, so you should always check
+for this case. Don't just use its value in expressions unless you're sure that
+the :meth:`send` method will be the only method used to resume your generator
+function.
+
+In addition to :meth:`send`, there are two other new methods on generators:
+
+* :meth:`throw(type, value=None, traceback=None)` is used to raise an exception
+ inside the generator; the exception is raised by the :keyword:`yield` expression
+ where the generator's execution is paused.
+
+* :meth:`close` raises a new :exc:`GeneratorExit` exception inside the generator
+ to terminate the iteration. On receiving this exception, the generator's code
+ must either raise :exc:`GeneratorExit` or :exc:`StopIteration`. Catching the
+ :exc:`GeneratorExit` exception and returning a value is illegal and will trigger
+ a :exc:`RuntimeError`; if the function raises some other exception, that
+ exception is propagated to the caller. :meth:`close` will also be called by
+ Python's garbage collector when the generator is garbage-collected.
+
+ If you need to run cleanup code when a :exc:`GeneratorExit` occurs, I suggest
+ using a ``try: ... finally:`` suite instead of catching :exc:`GeneratorExit`.
+
+The cumulative effect of these changes is to turn generators from one-way
+producers of information into both producers and consumers.
+
+Generators also become *coroutines*, a more generalized form of subroutines.
+Subroutines are entered at one point and exited at another point (the top of the
+function, and a :keyword:`return` statement), but coroutines can be entered,
+exited, and resumed at many different points (the :keyword:`yield` statements).
+We'll have to figure out patterns for using coroutines effectively in Python.
+
+The addition of the :meth:`close` method has one side effect that isn't obvious.
+:meth:`close` is called when a generator is garbage-collected, so this means the
+generator's code gets one last chance to run before the generator is destroyed.
+This last chance means that ``try...finally`` statements in generators can now
+be guaranteed to work; the :keyword:`finally` clause will now always get a
+chance to run. The syntactic restriction that you couldn't mix :keyword:`yield`
+statements with a ``try...finally`` suite has therefore been removed. This
+seems like a minor bit of language trivia, but using generators and
+``try...finally`` is actually necessary in order to implement the
+:keyword:`with` statement described by PEP 343. I'll look at this new statement
+in the following section.
+
+Another even more esoteric effect of this change: previously, the
+:attr:`gi_frame` attribute of a generator was always a frame object. It's now
+possible for :attr:`gi_frame` to be ``None`` once the generator has been
+exhausted.
+
+
+.. seealso::
+
+ :pep:`342` - Coroutines via Enhanced Generators
+ PEP written by Guido van Rossum and Phillip J. Eby; implemented by Phillip J.
+ Eby. Includes examples of some fancier uses of generators as coroutines.
+
+ Earlier versions of these features were proposed in :pep:`288` by Raymond
+ Hettinger and :pep:`325` by Samuele Pedroni.
+
+ http://en.wikipedia.org/wiki/Coroutine
+ The Wikipedia entry for coroutines.
+
+ http://www.sidhe.org/~dan/blog/archives/000178.html
+ An explanation of coroutines from a Perl point of view, written by Dan Sugalski.
+
+.. % ======================================================================
+
+
+.. _pep-343:
+
+PEP 343: The 'with' statement
+=============================
+
+The ':keyword:`with`' statement clarifies code that previously would use
+``try...finally`` blocks to ensure that clean-up code is executed. In this
+section, I'll discuss the statement as it will commonly be used. In the next
+section, I'll examine the implementation details and show how to write objects
+for use with this statement.
+
+The ':keyword:`with`' statement is a new control-flow structure whose basic
+structure is::
+
+ with expression [as variable]:
+ with-block
+
+The expression is evaluated, and it should result in an object that supports the
+context management protocol (that is, has :meth:`__enter__` and :meth:`__exit__`
+methods.
+
+The object's :meth:`__enter__` is called before *with-block* is executed and
+therefore can run set-up code. It also may return a value that is bound to the
+name *variable*, if given. (Note carefully that *variable* is *not* assigned
+the result of *expression*.)
+
+After execution of the *with-block* is finished, the object's :meth:`__exit__`
+method is called, even if the block raised an exception, and can therefore run
+clean-up code.
+
+To enable the statement in Python 2.5, you need to add the following directive
+to your module::
+
+ from __future__ import with_statement
+
+The statement will always be enabled in Python 2.6.
+
+Some standard Python objects now support the context management protocol and can
+be used with the ':keyword:`with`' statement. File objects are one example::
+
+ with open('/etc/passwd', 'r') as f:
+ for line in f:
+ print line
+ ... more processing code ...
+
+After this statement has executed, the file object in *f* will have been
+automatically closed, even if the :keyword:`for` loop raised an exception part-
+way through the block.
+
+.. note::
+
+ In this case, *f* is the same object created by :func:`open`, because
+ :meth:`file.__enter__` returns *self*.
+
+The :mod:`threading` module's locks and condition variables also support the
+':keyword:`with`' statement::
+
+ lock = threading.Lock()
+ with lock:
+ # Critical section of code
+ ...
+
+The lock is acquired before the block is executed and always released once the
+block is complete.
+
+The new :func:`localcontext` function in the :mod:`decimal` module makes it easy
+to save and restore the current decimal context, which encapsulates the desired
+precision and rounding characteristics for computations::
+
+ from decimal import Decimal, Context, localcontext
+
+ # Displays with default precision of 28 digits
+ v = Decimal('578')
+ print v.sqrt()
+
+ with localcontext(Context(prec=16)):
+ # All code in this block uses a precision of 16 digits.
+ # The original context is restored on exiting the block.
+ print v.sqrt()
+
+
+.. _context-managers:
+
+Writing Context Managers
+------------------------
+
+Under the hood, the ':keyword:`with`' statement is fairly complicated. Most
+people will only use ':keyword:`with`' in company with existing objects and
+don't need to know these details, so you can skip the rest of this section if
+you like. Authors of new objects will need to understand the details of the
+underlying implementation and should keep reading.
+
+A high-level explanation of the context management protocol is:
+
+* The expression is evaluated and should result in an object called a "context
+ manager". The context manager must have :meth:`__enter__` and :meth:`__exit__`
+ methods.
+
+* The context manager's :meth:`__enter__` method is called. The value returned
+ is assigned to *VAR*. If no ``'as VAR'`` clause is present, the value is simply
+ discarded.
+
+* The code in *BLOCK* is executed.
+
+* If *BLOCK* raises an exception, the :meth:`__exit__(type, value, traceback)`
+ is called with the exception details, the same values returned by
+ :func:`sys.exc_info`. The method's return value controls whether the exception
+ is re-raised: any false value re-raises the exception, and ``True`` will result
+ in suppressing it. You'll only rarely want to suppress the exception, because
+ if you do the author of the code containing the ':keyword:`with`' statement will
+ never realize anything went wrong.
+
+* If *BLOCK* didn't raise an exception, the :meth:`__exit__` method is still
+ called, but *type*, *value*, and *traceback* are all ``None``.
+
+Let's think through an example. I won't present detailed code but will only
+sketch the methods necessary for a database that supports transactions.
+
+(For people unfamiliar with database terminology: a set of changes to the
+database are grouped into a transaction. Transactions can be either committed,
+meaning that all the changes are written into the database, or rolled back,
+meaning that the changes are all discarded and the database is unchanged. See
+any database textbook for more information.)
+
+Let's assume there's an object representing a database connection. Our goal will
+be to let the user write code like this::
+
+ db_connection = DatabaseConnection()
+ with db_connection as cursor:
+ cursor.execute('insert into ...')
+ cursor.execute('delete from ...')
+ # ... more operations ...
+
+The transaction should be committed if the code in the block runs flawlessly or
+rolled back if there's an exception. Here's the basic interface for
+:class:`DatabaseConnection` that I'll assume::
+
+ class DatabaseConnection:
+ # Database interface
+ def cursor (self):
+ "Returns a cursor object and starts a new transaction"
+ def commit (self):
+ "Commits current transaction"
+ def rollback (self):
+ "Rolls back current transaction"
+
+The :meth:`__enter__` method is pretty easy, having only to start a new
+transaction. For this application the resulting cursor object would be a useful
+result, so the method will return it. The user can then add ``as cursor`` to
+their ':keyword:`with`' statement to bind the cursor to a variable name. ::
+
+ class DatabaseConnection:
+ ...
+ def __enter__ (self):
+ # Code to start a new transaction
+ cursor = self.cursor()
+ return cursor
+
+The :meth:`__exit__` method is the most complicated because it's where most of
+the work has to be done. The method has to check if an exception occurred. If
+there was no exception, the transaction is committed. The transaction is rolled
+back if there was an exception.
+
+In the code below, execution will just fall off the end of the function,
+returning the default value of ``None``. ``None`` is false, so the exception
+will be re-raised automatically. If you wished, you could be more explicit and
+add a :keyword:`return` statement at the marked location. ::
+
+ class DatabaseConnection:
+ ...
+ def __exit__ (self, type, value, tb):
+ if tb is None:
+ # No exception, so commit
+ self.commit()
+ else:
+ # Exception occurred, so rollback.
+ self.rollback()
+ # return False
+
+
+.. _module-contextlib:
+
+The contextlib module
+---------------------
+
+The new :mod:`contextlib` module provides some functions and a decorator that
+are useful for writing objects for use with the ':keyword:`with`' statement.
+
+The decorator is called :func:`contextmanager`, and lets you write a single
+generator function instead of defining a new class. The generator should yield
+exactly one value. The code up to the :keyword:`yield` will be executed as the
+:meth:`__enter__` method, and the value yielded will be the method's return
+value that will get bound to the variable in the ':keyword:`with`' statement's
+:keyword:`as` clause, if any. The code after the :keyword:`yield` will be
+executed in the :meth:`__exit__` method. Any exception raised in the block will
+be raised by the :keyword:`yield` statement.
+
+Our database example from the previous section could be written using this
+decorator as::
+
+ from contextlib import contextmanager
+
+ @contextmanager
+ def db_transaction (connection):
+ cursor = connection.cursor()
+ try:
+ yield cursor
+ except:
+ connection.rollback()
+ raise
+ else:
+ connection.commit()
+
+ db = DatabaseConnection()
+ with db_transaction(db) as cursor:
+ ...
+
+The :mod:`contextlib` module also has a :func:`nested(mgr1, mgr2, ...)` function
+that combines a number of context managers so you don't need to write nested
+':keyword:`with`' statements. In this example, the single ':keyword:`with`'
+statement both starts a database transaction and acquires a thread lock::
+
+ lock = threading.Lock()
+ with nested (db_transaction(db), lock) as (cursor, locked):
+ ...
+
+Finally, the :func:`closing(object)` function returns *object* so that it can be
+bound to a variable, and calls ``object.close`` at the end of the block. ::
+
+ import urllib, sys
+ from contextlib import closing
+
+ with closing(urllib.urlopen('http://www.yahoo.com')) as f:
+ for line in f:
+ sys.stdout.write(line)
+
+
+.. seealso::
+
+ :pep:`343` - The "with" statement
+ PEP written by Guido van Rossum and Nick Coghlan; implemented by Mike Bland,
+ Guido van Rossum, and Neal Norwitz. The PEP shows the code generated for a
+ ':keyword:`with`' statement, which can be helpful in learning how the statement
+ works.
+
+ The documentation for the :mod:`contextlib` module.
+
+.. % ======================================================================
+
+
+.. _pep-352:
+
+PEP 352: Exceptions as New-Style Classes
+========================================
+
+Exception classes can now be new-style classes, not just classic classes, and
+the built-in :exc:`Exception` class and all the standard built-in exceptions
+(:exc:`NameError`, :exc:`ValueError`, etc.) are now new-style classes.
+
+The inheritance hierarchy for exceptions has been rearranged a bit. In 2.5, the
+inheritance relationships are::
+
+ BaseException # New in Python 2.5
+ |- KeyboardInterrupt
+ |- SystemExit
+ |- Exception
+ |- (all other current built-in exceptions)
+
+This rearrangement was done because people often want to catch all exceptions
+that indicate program errors. :exc:`KeyboardInterrupt` and :exc:`SystemExit`
+aren't errors, though, and usually represent an explicit action such as the user
+hitting Control-C or code calling :func:`sys.exit`. A bare ``except:`` will
+catch all exceptions, so you commonly need to list :exc:`KeyboardInterrupt` and
+:exc:`SystemExit` in order to re-raise them. The usual pattern is::
+
+ try:
+ ...
+ except (KeyboardInterrupt, SystemExit):
+ raise
+ except:
+ # Log error...
+ # Continue running program...
+
+In Python 2.5, you can now write ``except Exception`` to achieve the same
+result, catching all the exceptions that usually indicate errors but leaving
+:exc:`KeyboardInterrupt` and :exc:`SystemExit` alone. As in previous versions,
+a bare ``except:`` still catches all exceptions.
+
+The goal for Python 3.0 is to require any class raised as an exception to derive
+from :exc:`BaseException` or some descendant of :exc:`BaseException`, and future
+releases in the Python 2.x series may begin to enforce this constraint.
+Therefore, I suggest you begin making all your exception classes derive from
+:exc:`Exception` now. It's been suggested that the bare ``except:`` form should
+be removed in Python 3.0, but Guido van Rossum hasn't decided whether to do this
+or not.
+
+Raising of strings as exceptions, as in the statement ``raise "Error
+occurred"``, is deprecated in Python 2.5 and will trigger a warning. The aim is
+to be able to remove the string-exception feature in a few releases.
+
+
+.. seealso::
+
+ :pep:`352` - Required Superclass for Exceptions
+ PEP written by Brett Cannon and Guido van Rossum; implemented by Brett Cannon.
+
+.. % ======================================================================
+
+
+.. _pep-353:
+
+PEP 353: Using ssize_t as the index type
+========================================
+
+A wide-ranging change to Python's C API, using a new :ctype:`Py_ssize_t` type
+definition instead of :ctype:`int`, will permit the interpreter to handle more
+data on 64-bit platforms. This change doesn't affect Python's capacity on 32-bit
+platforms.
+
+Various pieces of the Python interpreter used C's :ctype:`int` type to store
+sizes or counts; for example, the number of items in a list or tuple were stored
+in an :ctype:`int`. The C compilers for most 64-bit platforms still define
+:ctype:`int` as a 32-bit type, so that meant that lists could only hold up to
+``2**31 - 1`` = 2147483647 items. (There are actually a few different
+programming models that 64-bit C compilers can use -- see
+http://www.unix.org/version2/whatsnew/lp64_wp.html for a discussion -- but the
+most commonly available model leaves :ctype:`int` as 32 bits.)
+
+A limit of 2147483647 items doesn't really matter on a 32-bit platform because
+you'll run out of memory before hitting the length limit. Each list item
+requires space for a pointer, which is 4 bytes, plus space for a
+:ctype:`PyObject` representing the item. 2147483647\*4 is already more bytes
+than a 32-bit address space can contain.
+
+It's possible to address that much memory on a 64-bit platform, however. The
+pointers for a list that size would only require 16 GiB of space, so it's not
+unreasonable that Python programmers might construct lists that large.
+Therefore, the Python interpreter had to be changed to use some type other than
+:ctype:`int`, and this will be a 64-bit type on 64-bit platforms. The change
+will cause incompatibilities on 64-bit machines, so it was deemed worth making
+the transition now, while the number of 64-bit users is still relatively small.
+(In 5 or 10 years, we may *all* be on 64-bit machines, and the transition would
+be more painful then.)
+
+This change most strongly affects authors of C extension modules. Python
+strings and container types such as lists and tuples now use
+:ctype:`Py_ssize_t` to store their size. Functions such as
+:cfunc:`PyList_Size` now return :ctype:`Py_ssize_t`. Code in extension modules
+may therefore need to have some variables changed to :ctype:`Py_ssize_t`.
+
+The :cfunc:`PyArg_ParseTuple` and :cfunc:`Py_BuildValue` functions have a new
+conversion code, ``n``, for :ctype:`Py_ssize_t`. :cfunc:`PyArg_ParseTuple`'s
+``s#`` and ``t#`` still output :ctype:`int` by default, but you can define the
+macro :cmacro:`PY_SSIZE_T_CLEAN` before including :file:`Python.h` to make
+them return :ctype:`Py_ssize_t`.
+
+:pep:`353` has a section on conversion guidelines that extension authors should
+read to learn about supporting 64-bit platforms.
+
+
+.. seealso::
+
+ :pep:`353` - Using ssize_t as the index type
+ PEP written and implemented by Martin von Löwis.
+
+.. % ======================================================================
+
+
+.. _pep-357:
+
+PEP 357: The '__index__' method
+===============================
+
+The NumPy developers had a problem that could only be solved by adding a new
+special method, :meth:`__index__`. When using slice notation, as in
+``[start:stop:step]``, the values of the *start*, *stop*, and *step* indexes
+must all be either integers or long integers. NumPy defines a variety of
+specialized integer types corresponding to unsigned and signed integers of 8,
+16, 32, and 64 bits, but there was no way to signal that these types could be
+used as slice indexes.
+
+Slicing can't just use the existing :meth:`__int__` method because that method
+is also used to implement coercion to integers. If slicing used
+:meth:`__int__`, floating-point numbers would also become legal slice indexes
+and that's clearly an undesirable behaviour.
+
+Instead, a new special method called :meth:`__index__` was added. It takes no
+arguments and returns an integer giving the slice index to use. For example::
+
+ class C:
+ def __index__ (self):
+ return self.value
+
+The return value must be either a Python integer or long integer. The
+interpreter will check that the type returned is correct, and raises a
+:exc:`TypeError` if this requirement isn't met.
+
+A corresponding :attr:`nb_index` slot was added to the C-level
+:ctype:`PyNumberMethods` structure to let C extensions implement this protocol.
+:cfunc:`PyNumber_Index(obj)` can be used in extension code to call the
+:meth:`__index__` function and retrieve its result.
+
+
+.. seealso::
+
+ :pep:`357` - Allowing Any Object to be Used for Slicing
+ PEP written and implemented by Travis Oliphant.
+
+.. % ======================================================================
+
+
+.. _other-lang:
+
+Other Language Changes
+======================
+
+Here are all of the changes that Python 2.5 makes to the core Python language.
+
+* The :class:`dict` type has a new hook for letting subclasses provide a default
+ value when a key isn't contained in the dictionary. When a key isn't found, the
+ dictionary's :meth:`__missing__(key)` method will be called. This hook is used
+ to implement the new :class:`defaultdict` class in the :mod:`collections`
+ module. The following example defines a dictionary that returns zero for any
+ missing key::
+
+ class zerodict (dict):
+ def __missing__ (self, key):
+ return 0
+
+ d = zerodict({1:1, 2:2})
+ print d[1], d[2] # Prints 1, 2
+ print d[3], d[4] # Prints 0, 0
+
+* Both 8-bit and Unicode strings have new :meth:`partition(sep)` and
+ :meth:`rpartition(sep)` methods that simplify a common use case.
+
+ The :meth:`find(S)` method is often used to get an index which is then used to
+ slice the string and obtain the pieces that are before and after the separator.
+ :meth:`partition(sep)` condenses this pattern into a single method call that
+ returns a 3-tuple containing the substring before the separator, the separator
+ itself, and the substring after the separator. If the separator isn't found,
+ the first element of the tuple is the entire string and the other two elements
+ are empty. :meth:`rpartition(sep)` also returns a 3-tuple but starts searching
+ from the end of the string; the ``r`` stands for 'reverse'.
+
+ Some examples::
+
+ >>> ('http://www.python.org').partition('://')
+ ('http', '://', 'www.python.org')
+ >>> ('file:/usr/share/doc/index.html').partition('://')
+ ('file:/usr/share/doc/index.html', '', '')
+ >>> (u'Subject: a quick question').partition(':')
+ (u'Subject', u':', u' a quick question')
+ >>> 'www.python.org'.rpartition('.')
+ ('www.python', '.', 'org')
+ >>> 'www.python.org'.rpartition(':')
+ ('', '', 'www.python.org')
+
+ (Implemented by Fredrik Lundh following a suggestion by Raymond Hettinger.)
+
+* The :meth:`startswith` and :meth:`endswith` methods of string types now accept
+ tuples of strings to check for. ::
+
+ def is_image_file (filename):
+ return filename.endswith(('.gif', '.jpg', '.tiff'))
+
+ (Implemented by Georg Brandl following a suggestion by Tom Lynn.)
+
+ .. % RFE #1491485
+
+* The :func:`min` and :func:`max` built-in functions gained a ``key`` keyword
+ parameter analogous to the ``key`` argument for :meth:`sort`. This parameter
+ supplies a function that takes a single argument and is called for every value
+ in the list; :func:`min`/:func:`max` will return the element with the
+ smallest/largest return value from this function. For example, to find the
+ longest string in a list, you can do::
+
+ L = ['medium', 'longest', 'short']
+ # Prints 'longest'
+ print max(L, key=len)
+ # Prints 'short', because lexicographically 'short' has the largest value
+ print max(L)
+
+ (Contributed by Steven Bethard and Raymond Hettinger.)
+
+* Two new built-in functions, :func:`any` and :func:`all`, evaluate whether an
+ iterator contains any true or false values. :func:`any` returns :const:`True`
+ if any value returned by the iterator is true; otherwise it will return
+ :const:`False`. :func:`all` returns :const:`True` only if all of the values
+ returned by the iterator evaluate as true. (Suggested by Guido van Rossum, and
+ implemented by Raymond Hettinger.)
+
+* The result of a class's :meth:`__hash__` method can now be either a long
+ integer or a regular integer. If a long integer is returned, the hash of that
+ value is taken. In earlier versions the hash value was required to be a
+ regular integer, but in 2.5 the :func:`id` built-in was changed to always
+ return non-negative numbers, and users often seem to use ``id(self)`` in
+ :meth:`__hash__` methods (though this is discouraged).
+
+ .. % Bug #1536021
+
+* ASCII is now the default encoding for modules. It's now a syntax error if a
+ module contains string literals with 8-bit characters but doesn't have an
+ encoding declaration. In Python 2.4 this triggered a warning, not a syntax
+ error. See :pep:`263` for how to declare a module's encoding; for example, you
+ might add a line like this near the top of the source file::
+
+ # -*- coding: latin1 -*-
+
+* A new warning, :class:`UnicodeWarning`, is triggered when you attempt to
+ compare a Unicode string and an 8-bit string that can't be converted to Unicode
+ using the default ASCII encoding. The result of the comparison is false::
+
+ >>> chr(128) == unichr(128) # Can't convert chr(128) to Unicode
+ __main__:1: UnicodeWarning: Unicode equal comparison failed
+ to convert both arguments to Unicode - interpreting them
+ as being unequal
+ False
+ >>> chr(127) == unichr(127) # chr(127) can be converted
+ True
+
+ Previously this would raise a :class:`UnicodeDecodeError` exception, but in 2.5
+ this could result in puzzling problems when accessing a dictionary. If you
+ looked up ``unichr(128)`` and ``chr(128)`` was being used as a key, you'd get a
+ :class:`UnicodeDecodeError` exception. Other changes in 2.5 resulted in this
+ exception being raised instead of suppressed by the code in :file:`dictobject.c`
+ that implements dictionaries.
+
+ Raising an exception for such a comparison is strictly correct, but the change
+ might have broken code, so instead :class:`UnicodeWarning` was introduced.
+
+ (Implemented by Marc-André Lemburg.)
+
+* One error that Python programmers sometimes make is forgetting to include an
+ :file:`__init__.py` module in a package directory. Debugging this mistake can be
+ confusing, and usually requires running Python with the :option:`-v` switch to
+ log all the paths searched. In Python 2.5, a new :exc:`ImportWarning` warning is
+ triggered when an import would have picked up a directory as a package but no
+ :file:`__init__.py` was found. This warning is silently ignored by default;
+ provide the :option:`-Wd` option when running the Python executable to display
+ the warning message. (Implemented by Thomas Wouters.)
+
+* The list of base classes in a class definition can now be empty. As an
+ example, this is now legal::
+
+ class C():
+ pass
+
+ (Implemented by Brett Cannon.)
+
+.. % ======================================================================
+
+
+.. _interactive:
+
+Interactive Interpreter Changes
+-------------------------------
+
+In the interactive interpreter, ``quit`` and ``exit`` have long been strings so
+that new users get a somewhat helpful message when they try to quit::
+
+ >>> quit
+ 'Use Ctrl-D (i.e. EOF) to exit.'
+
+In Python 2.5, ``quit`` and ``exit`` are now objects that still produce string
+representations of themselves, but are also callable. Newbies who try ``quit()``
+or ``exit()`` will now exit the interpreter as they expect. (Implemented by
+Georg Brandl.)
+
+The Python executable now accepts the standard long options :option:`--help`
+and :option:`--version`; on Windows, it also accepts the :option:`/?` option
+for displaying a help message. (Implemented by Georg Brandl.)
+
+.. % ======================================================================
+
+
+.. _opts:
+
+Optimizations
+-------------
+
+Several of the optimizations were developed at the NeedForSpeed sprint, an event
+held in Reykjavik, Iceland, from May 21--28 2006. The sprint focused on speed
+enhancements to the CPython implementation and was funded by EWT LLC with local
+support from CCP Games. Those optimizations added at this sprint are specially
+marked in the following list.
+
+* When they were introduced in Python 2.4, the built-in :class:`set` and
+ :class:`frozenset` types were built on top of Python's dictionary type. In 2.5
+ the internal data structure has been customized for implementing sets, and as a
+ result sets will use a third less memory and are somewhat faster. (Implemented
+ by Raymond Hettinger.)
+
+* The speed of some Unicode operations, such as finding substrings, string
+ splitting, and character map encoding and decoding, has been improved.
+ (Substring search and splitting improvements were added by Fredrik Lundh and
+ Andrew Dalke at the NeedForSpeed sprint. Character maps were improved by Walter
+ Dörwald and Martin von Löwis.)
+
+ .. % Patch 1313939, 1359618
+
+* The :func:`long(str, base)` function is now faster on long digit strings
+ because fewer intermediate results are calculated. The peak is for strings of
+ around 800--1000 digits where the function is 6 times faster. (Contributed by
+ Alan McIntyre and committed at the NeedForSpeed sprint.)
+
+ .. % Patch 1442927
+
+* It's now illegal to mix iterating over a file with ``for line in file`` and
+ calling the file object's :meth:`read`/:meth:`readline`/:meth:`readlines`
+ methods. Iteration uses an internal buffer and the :meth:`read\*` methods
+ don't use that buffer. Instead they would return the data following the
+ buffer, causing the data to appear out of order. Mixing iteration and these
+ methods will now trigger a :exc:`ValueError` from the :meth:`read\*` method.
+ (Implemented by Thomas Wouters.)
+
+ .. % Patch 1397960
+
+* The :mod:`struct` module now compiles structure format strings into an
+ internal representation and caches this representation, yielding a 20% speedup.
+ (Contributed by Bob Ippolito at the NeedForSpeed sprint.)
+
+* The :mod:`re` module got a 1 or 2% speedup by switching to Python's allocator
+ functions instead of the system's :cfunc:`malloc` and :cfunc:`free`.
+ (Contributed by Jack Diederich at the NeedForSpeed sprint.)
+
+* The code generator's peephole optimizer now performs simple constant folding
+ in expressions. If you write something like ``a = 2+3``, the code generator
+ will do the arithmetic and produce code corresponding to ``a = 5``. (Proposed
+ and implemented by Raymond Hettinger.)
+
+* Function calls are now faster because code objects now keep the most recently
+ finished frame (a "zombie frame") in an internal field of the code object,
+ reusing it the next time the code object is invoked. (Original patch by Michael
+ Hudson, modified by Armin Rigo and Richard Jones; committed at the NeedForSpeed
+ sprint.) Frame objects are also slightly smaller, which may improve cache
+ locality and reduce memory usage a bit. (Contributed by Neal Norwitz.)
+
+ .. % Patch 876206
+ .. % Patch 1337051
+
+* Python's built-in exceptions are now new-style classes, a change that speeds
+ up instantiation considerably. Exception handling in Python 2.5 is therefore
+ about 30% faster than in 2.4. (Contributed by Richard Jones, Georg Brandl and
+ Sean Reifschneider at the NeedForSpeed sprint.)
+
+* Importing now caches the paths tried, recording whether they exist or not so
+ that the interpreter makes fewer :cfunc:`open` and :cfunc:`stat` calls on
+ startup. (Contributed by Martin von Löwis and Georg Brandl.)
+
+ .. % Patch 921466
+
+.. % ======================================================================
+
+
+.. _modules:
+
+New, Improved, and Removed Modules
+==================================
+
+The standard library received many enhancements and bug fixes in Python 2.5.
+Here's a partial list of the most notable changes, sorted alphabetically by
+module name. Consult the :file:`Misc/NEWS` file in the source tree for a more
+complete list of changes, or look through the SVN logs for all the details.
+
+* The :mod:`audioop` module now supports the a-LAW encoding, and the code for
+ u-LAW encoding has been improved. (Contributed by Lars Immisch.)
+
+* The :mod:`codecs` module gained support for incremental codecs. The
+ :func:`codec.lookup` function now returns a :class:`CodecInfo` instance instead
+ of a tuple. :class:`CodecInfo` instances behave like a 4-tuple to preserve
+ backward compatibility but also have the attributes :attr:`encode`,
+ :attr:`decode`, :attr:`incrementalencoder`, :attr:`incrementaldecoder`,
+ :attr:`streamwriter`, and :attr:`streamreader`. Incremental codecs can receive
+ input and produce output in multiple chunks; the output is the same as if the
+ entire input was fed to the non-incremental codec. See the :mod:`codecs` module
+ documentation for details. (Designed and implemented by Walter Dörwald.)
+
+ .. % Patch 1436130
+
+* The :mod:`collections` module gained a new type, :class:`defaultdict`, that
+ subclasses the standard :class:`dict` type. The new type mostly behaves like a
+ dictionary but constructs a default value when a key isn't present,
+ automatically adding it to the dictionary for the requested key value.
+
+ The first argument to :class:`defaultdict`'s constructor is a factory function
+ that gets called whenever a key is requested but not found. This factory
+ function receives no arguments, so you can use built-in type constructors such
+ as :func:`list` or :func:`int`. For example, you can make an index of words
+ based on their initial letter like this::
+
+ words = """Nel mezzo del cammin di nostra vita
+ mi ritrovai per una selva oscura
+ che la diritta via era smarrita""".lower().split()
+
+ index = defaultdict(list)
+
+ for w in words:
+ init_letter = w[0]
+ index[init_letter].append(w)
+
+ Printing ``index`` results in the following output::
+
+ defaultdict(<type 'list'>, {'c': ['cammin', 'che'], 'e': ['era'],
+ 'd': ['del', 'di', 'diritta'], 'm': ['mezzo', 'mi'],
+ 'l': ['la'], 'o': ['oscura'], 'n': ['nel', 'nostra'],
+ 'p': ['per'], 's': ['selva', 'smarrita'],
+ 'r': ['ritrovai'], 'u': ['una'], 'v': ['vita', 'via']}
+
+ (Contributed by Guido van Rossum.)
+
+* The :class:`deque` double-ended queue type supplied by the :mod:`collections`
+ module now has a :meth:`remove(value)` method that removes the first occurrence
+ of *value* in the queue, raising :exc:`ValueError` if the value isn't found.
+ (Contributed by Raymond Hettinger.)
+
+* New module: The :mod:`contextlib` module contains helper functions for use
+ with the new ':keyword:`with`' statement. See section :ref:`module-contextlib`
+ for more about this module.
+
+* New module: The :mod:`cProfile` module is a C implementation of the existing
+ :mod:`profile` module that has much lower overhead. The module's interface is
+ the same as :mod:`profile`: you run ``cProfile.run('main()')`` to profile a
+ function, can save profile data to a file, etc. It's not yet known if the
+ Hotshot profiler, which is also written in C but doesn't match the
+ :mod:`profile` module's interface, will continue to be maintained in future
+ versions of Python. (Contributed by Armin Rigo.)
+
+ Also, the :mod:`pstats` module for analyzing the data measured by the profiler
+ now supports directing the output to any file object by supplying a *stream*
+ argument to the :class:`Stats` constructor. (Contributed by Skip Montanaro.)
+
+* The :mod:`csv` module, which parses files in comma-separated value format,
+ received several enhancements and a number of bugfixes. You can now set the
+ maximum size in bytes of a field by calling the
+ :meth:`csv.field_size_limit(new_limit)` function; omitting the *new_limit*
+ argument will return the currently-set limit. The :class:`reader` class now has
+ a :attr:`line_num` attribute that counts the number of physical lines read from
+ the source; records can span multiple physical lines, so :attr:`line_num` is not
+ the same as the number of records read.
+
+ The CSV parser is now stricter about multi-line quoted fields. Previously, if a
+ line ended within a quoted field without a terminating newline character, a
+ newline would be inserted into the returned field. This behavior caused problems
+ when reading files that contained carriage return characters within fields, so
+ the code was changed to return the field without inserting newlines. As a
+ consequence, if newlines embedded within fields are important, the input should
+ be split into lines in a manner that preserves the newline characters.
+
+ (Contributed by Skip Montanaro and Andrew McNamara.)
+
+* The :class:`datetime` class in the :mod:`datetime` module now has a
+ :meth:`strptime(string, format)` method for parsing date strings, contributed
+ by Josh Spoerri. It uses the same format characters as :func:`time.strptime` and
+ :func:`time.strftime`::
+
+ from datetime import datetime
+
+ ts = datetime.strptime('10:13:15 2006-03-07',
+ '%H:%M:%S %Y-%m-%d')
+
+* The :meth:`SequenceMatcher.get_matching_blocks` method in the :mod:`difflib`
+ module now guarantees to return a minimal list of blocks describing matching
+ subsequences. Previously, the algorithm would occasionally break a block of
+ matching elements into two list entries. (Enhancement by Tim Peters.)
+
+* The :mod:`doctest` module gained a ``SKIP`` option that keeps an example from
+ being executed at all. This is intended for code snippets that are usage
+ examples intended for the reader and aren't actually test cases.
+
+ An *encoding* parameter was added to the :func:`testfile` function and the
+ :class:`DocFileSuite` class to specify the file's encoding. This makes it
+ easier to use non-ASCII characters in tests contained within a docstring.
+ (Contributed by Bjorn Tillenius.)
+
+ .. % Patch 1080727
+
+* The :mod:`email` package has been updated to version 4.0. (Contributed by
+ Barry Warsaw.)
+
+ .. % XXX need to provide some more detail here
+
+* The :mod:`fileinput` module was made more flexible. Unicode filenames are now
+ supported, and a *mode* parameter that defaults to ``"r"`` was added to the
+ :func:`input` function to allow opening files in binary or universal-newline
+ mode. Another new parameter, *openhook*, lets you use a function other than
+ :func:`open` to open the input files. Once you're iterating over the set of
+ files, the :class:`FileInput` object's new :meth:`fileno` returns the file
+ descriptor for the currently opened file. (Contributed by Georg Brandl.)
+
+* In the :mod:`gc` module, the new :func:`get_count` function returns a 3-tuple
+ containing the current collection counts for the three GC generations. This is
+ accounting information for the garbage collector; when these counts reach a
+ specified threshold, a garbage collection sweep will be made. The existing
+ :func:`gc.collect` function now takes an optional *generation* argument of 0, 1,
+ or 2 to specify which generation to collect. (Contributed by Barry Warsaw.)
+
+* The :func:`nsmallest` and :func:`nlargest` functions in the :mod:`heapq`
+ module now support a ``key`` keyword parameter similar to the one provided by
+ the :func:`min`/:func:`max` functions and the :meth:`sort` methods. For
+ example::
+
+ >>> import heapq
+ >>> L = ["short", 'medium', 'longest', 'longer still']
+ >>> heapq.nsmallest(2, L) # Return two lowest elements, lexicographically
+ ['longer still', 'longest']
+ >>> heapq.nsmallest(2, L, key=len) # Return two shortest elements
+ ['short', 'medium']
+
+ (Contributed by Raymond Hettinger.)
+
+* The :func:`itertools.islice` function now accepts ``None`` for the start and
+ step arguments. This makes it more compatible with the attributes of slice
+ objects, so that you can now write the following::
+
+ s = slice(5) # Create slice object
+ itertools.islice(iterable, s.start, s.stop, s.step)
+
+ (Contributed by Raymond Hettinger.)
+
+* The :func:`format` function in the :mod:`locale` module has been modified and
+ two new functions were added, :func:`format_string` and :func:`currency`.
+
+ The :func:`format` function's *val* parameter could previously be a string as
+ long as no more than one %char specifier appeared; now the parameter must be
+ exactly one %char specifier with no surrounding text. An optional *monetary*
+ parameter was also added which, if ``True``, will use the locale's rules for
+ formatting currency in placing a separator between groups of three digits.
+
+ To format strings with multiple %char specifiers, use the new
+ :func:`format_string` function that works like :func:`format` but also supports
+ mixing %char specifiers with arbitrary text.
+
+ A new :func:`currency` function was also added that formats a number according
+ to the current locale's settings.
+
+ (Contributed by Georg Brandl.)
+
+ .. % Patch 1180296
+
+* The :mod:`mailbox` module underwent a massive rewrite to add the capability to
+ modify mailboxes in addition to reading them. A new set of classes that include
+ :class:`mbox`, :class:`MH`, and :class:`Maildir` are used to read mailboxes, and
+ have an :meth:`add(message)` method to add messages, :meth:`remove(key)` to
+ remove messages, and :meth:`lock`/:meth:`unlock` to lock/unlock the mailbox.
+ The following example converts a maildir-format mailbox into an mbox-format
+ one::
+
+ import mailbox
+
+ # 'factory=None' uses email.Message.Message as the class representing
+ # individual messages.
+ src = mailbox.Maildir('maildir', factory=None)
+ dest = mailbox.mbox('/tmp/mbox')
+
+ for msg in src:
+ dest.add(msg)
+
+ (Contributed by Gregory K. Johnson. Funding was provided by Google's 2005
+ Summer of Code.)
+
+* New module: the :mod:`msilib` module allows creating Microsoft Installer
+ :file:`.msi` files and CAB files. Some support for reading the :file:`.msi`
+ database is also included. (Contributed by Martin von Löwis.)
+
+* The :mod:`nis` module now supports accessing domains other than the system
+ default domain by supplying a *domain* argument to the :func:`nis.match` and
+ :func:`nis.maps` functions. (Contributed by Ben Bell.)
+
+* The :mod:`operator` module's :func:`itemgetter` and :func:`attrgetter`
+ functions now support multiple fields. A call such as
+ ``operator.attrgetter('a', 'b')`` will return a function that retrieves the
+ :attr:`a` and :attr:`b` attributes. Combining this new feature with the
+ :meth:`sort` method's ``key`` parameter lets you easily sort lists using
+ multiple fields. (Contributed by Raymond Hettinger.)
+
+* The :mod:`optparse` module was updated to version 1.5.1 of the Optik library.
+ The :class:`OptionParser` class gained an :attr:`epilog` attribute, a string
+ that will be printed after the help message, and a :meth:`destroy` method to
+ break reference cycles created by the object. (Contributed by Greg Ward.)
+
+* The :mod:`os` module underwent several changes. The :attr:`stat_float_times`
+ variable now defaults to true, meaning that :func:`os.stat` will now return time
+ values as floats. (This doesn't necessarily mean that :func:`os.stat` will
+ return times that are precise to fractions of a second; not all systems support
+ such precision.)
+
+ Constants named :attr:`os.SEEK_SET`, :attr:`os.SEEK_CUR`, and
+ :attr:`os.SEEK_END` have been added; these are the parameters to the
+ :func:`os.lseek` function. Two new constants for locking are
+ :attr:`os.O_SHLOCK` and :attr:`os.O_EXLOCK`.
+
+ Two new functions, :func:`wait3` and :func:`wait4`, were added. They're similar
+ the :func:`waitpid` function which waits for a child process to exit and returns
+ a tuple of the process ID and its exit status, but :func:`wait3` and
+ :func:`wait4` return additional information. :func:`wait3` doesn't take a
+ process ID as input, so it waits for any child process to exit and returns a
+ 3-tuple of *process-id*, *exit-status*, *resource-usage* as returned from the
+ :func:`resource.getrusage` function. :func:`wait4(pid)` does take a process ID.
+ (Contributed by Chad J. Schroeder.)
+
+ On FreeBSD, the :func:`os.stat` function now returns times with nanosecond
+ resolution, and the returned object now has :attr:`st_gen` and
+ :attr:`st_birthtime`. The :attr:`st_flags` member is also available, if the
+ platform supports it. (Contributed by Antti Louko and Diego Pettenò.)
+
+ .. % (Patch 1180695, 1212117)
+
+* The Python debugger provided by the :mod:`pdb` module can now store lists of
+ commands to execute when a breakpoint is reached and execution stops. Once
+ breakpoint #1 has been created, enter ``commands 1`` and enter a series of
+ commands to be executed, finishing the list with ``end``. The command list can
+ include commands that resume execution, such as ``continue`` or ``next``.
+ (Contributed by Grégoire Dooms.)
+
+ .. % Patch 790710
+
+* The :mod:`pickle` and :mod:`cPickle` modules no longer accept a return value
+ of ``None`` from the :meth:`__reduce__` method; the method must return a tuple
+ of arguments instead. The ability to return ``None`` was deprecated in Python
+ 2.4, so this completes the removal of the feature.
+
+* The :mod:`pkgutil` module, containing various utility functions for finding
+ packages, was enhanced to support PEP 302's import hooks and now also works for
+ packages stored in ZIP-format archives. (Contributed by Phillip J. Eby.)
+
+* The pybench benchmark suite by Marc-André Lemburg is now included in the
+ :file:`Tools/pybench` directory. The pybench suite is an improvement on the
+ commonly used :file:`pystone.py` program because pybench provides a more
+ detailed measurement of the interpreter's speed. It times particular operations
+ such as function calls, tuple slicing, method lookups, and numeric operations,
+ instead of performing many different operations and reducing the result to a
+ single number as :file:`pystone.py` does.
+
+* The :mod:`pyexpat` module now uses version 2.0 of the Expat parser.
+ (Contributed by Trent Mick.)
+
+* The :class:`Queue` class provided by the :mod:`Queue` module gained two new
+ methods. :meth:`join` blocks until all items in the queue have been retrieved
+ and all processing work on the items have been completed. Worker threads call
+ the other new method, :meth:`task_done`, to signal that processing for an item
+ has been completed. (Contributed by Raymond Hettinger.)
+
+* The old :mod:`regex` and :mod:`regsub` modules, which have been deprecated
+ ever since Python 2.0, have finally been deleted. Other deleted modules:
+ :mod:`statcache`, :mod:`tzparse`, :mod:`whrandom`.
+
+* Also deleted: the :file:`lib-old` directory, which includes ancient modules
+ such as :mod:`dircmp` and :mod:`ni`, was removed. :file:`lib-old` wasn't on the
+ default ``sys.path``, so unless your programs explicitly added the directory to
+ ``sys.path``, this removal shouldn't affect your code.
+
+* The :mod:`rlcompleter` module is no longer dependent on importing the
+ :mod:`readline` module and therefore now works on non-Unix platforms. (Patch
+ from Robert Kiendl.)
+
+ .. % Patch #1472854
+
+* The :mod:`SimpleXMLRPCServer` and :mod:`DocXMLRPCServer` classes now have a
+ :attr:`rpc_paths` attribute that constrains XML-RPC operations to a limited set
+ of URL paths; the default is to allow only ``'/'`` and ``'/RPC2'``. Setting
+ :attr:`rpc_paths` to ``None`` or an empty tuple disables this path checking.
+
+ .. % Bug #1473048
+
+* The :mod:`socket` module now supports :const:`AF_NETLINK` sockets on Linux,
+ thanks to a patch from Philippe Biondi. Netlink sockets are a Linux-specific
+ mechanism for communications between a user-space process and kernel code; an
+ introductory article about them is at http://www.linuxjournal.com/article/7356.
+ In Python code, netlink addresses are represented as a tuple of 2 integers,
+ ``(pid, group_mask)``.
+
+ Two new methods on socket objects, :meth:`recv_into(buffer)` and
+ :meth:`recvfrom_into(buffer)`, store the received data in an object that
+ supports the buffer protocol instead of returning the data as a string. This
+ means you can put the data directly into an array or a memory-mapped file.
+
+ Socket objects also gained :meth:`getfamily`, :meth:`gettype`, and
+ :meth:`getproto` accessor methods to retrieve the family, type, and protocol
+ values for the socket.
+
+* New module: the :mod:`spwd` module provides functions for accessing the shadow
+ password database on systems that support shadow passwords.
+
+* The :mod:`struct` is now faster because it compiles format strings into
+ :class:`Struct` objects with :meth:`pack` and :meth:`unpack` methods. This is
+ similar to how the :mod:`re` module lets you create compiled regular expression
+ objects. You can still use the module-level :func:`pack` and :func:`unpack`
+ functions; they'll create :class:`Struct` objects and cache them. Or you can
+ use :class:`Struct` instances directly::
+
+ s = struct.Struct('ih3s')
+
+ data = s.pack(1972, 187, 'abc')
+ year, number, name = s.unpack(data)
+
+ You can also pack and unpack data to and from buffer objects directly using the
+ :meth:`pack_into(buffer, offset, v1, v2, ...)` and :meth:`unpack_from(buffer,
+ offset)` methods. This lets you store data directly into an array or a memory-
+ mapped file.
+
+ (:class:`Struct` objects were implemented by Bob Ippolito at the NeedForSpeed
+ sprint. Support for buffer objects was added by Martin Blais, also at the
+ NeedForSpeed sprint.)
+
+* The Python developers switched from CVS to Subversion during the 2.5
+ development process. Information about the exact build version is available as
+ the ``sys.subversion`` variable, a 3-tuple of ``(interpreter-name, branch-name,
+ revision-range)``. For example, at the time of writing my copy of 2.5 was
+ reporting ``('CPython', 'trunk', '45313:45315')``.
+
+ This information is also available to C extensions via the
+ :cfunc:`Py_GetBuildInfo` function that returns a string of build information
+ like this: ``"trunk:45355:45356M, Apr 13 2006, 07:42:19"``. (Contributed by
+ Barry Warsaw.)
+
+* Another new function, :func:`sys._current_frames`, returns the current stack
+ frames for all running threads as a dictionary mapping thread identifiers to the
+ topmost stack frame currently active in that thread at the time the function is
+ called. (Contributed by Tim Peters.)
+
+* The :class:`TarFile` class in the :mod:`tarfile` module now has an
+ :meth:`extractall` method that extracts all members from the archive into the
+ current working directory. It's also possible to set a different directory as
+ the extraction target, and to unpack only a subset of the archive's members.
+
+ The compression used for a tarfile opened in stream mode can now be autodetected
+ using the mode ``'r|*'``. (Contributed by Lars Gustäbel.)
+
+ .. % patch 918101
+
+* The :mod:`threading` module now lets you set the stack size used when new
+ threads are created. The :func:`stack_size([*size*])` function returns the
+ currently configured stack size, and supplying the optional *size* parameter
+ sets a new value. Not all platforms support changing the stack size, but
+ Windows, POSIX threading, and OS/2 all do. (Contributed by Andrew MacIntyre.)
+
+ .. % Patch 1454481
+
+* The :mod:`unicodedata` module has been updated to use version 4.1.0 of the
+ Unicode character database. Version 3.2.0 is required by some specifications,
+ so it's still available as :attr:`unicodedata.ucd_3_2_0`.
+
+* New module: the :mod:`uuid` module generates universally unique identifiers
+ (UUIDs) according to :rfc:`4122`. The RFC defines several different UUID
+ versions that are generated from a starting string, from system properties, or
+ purely randomly. This module contains a :class:`UUID` class and functions
+ named :func:`uuid1`, :func:`uuid3`, :func:`uuid4`, and :func:`uuid5` to
+ generate different versions of UUID. (Version 2 UUIDs are not specified in
+ :rfc:`4122` and are not supported by this module.) ::
+
+ >>> import uuid
+ >>> # make a UUID based on the host ID and current time
+ >>> uuid.uuid1()
+ UUID('a8098c1a-f86e-11da-bd1a-00112444be1e')
+
+ >>> # make a UUID using an MD5 hash of a namespace UUID and a name
+ >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org')
+ UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e')
+
+ >>> # make a random UUID
+ >>> uuid.uuid4()
+ UUID('16fd2706-8baf-433b-82eb-8c7fada847da')
+
+ >>> # make a UUID using a SHA-1 hash of a namespace UUID and a name
+ >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org')
+ UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d')
+
+ (Contributed by Ka-Ping Yee.)
+
+* The :mod:`weakref` module's :class:`WeakKeyDictionary` and
+ :class:`WeakValueDictionary` types gained new methods for iterating over the
+ weak references contained in the dictionary. :meth:`iterkeyrefs` and
+ :meth:`keyrefs` methods were added to :class:`WeakKeyDictionary`, and
+ :meth:`itervaluerefs` and :meth:`valuerefs` were added to
+ :class:`WeakValueDictionary`. (Contributed by Fred L. Drake, Jr.)
+
+* The :mod:`webbrowser` module received a number of enhancements. It's now
+ usable as a script with ``python -m webbrowser``, taking a URL as the argument;
+ there are a number of switches to control the behaviour (:option:`-n` for a new
+ browser window, :option:`-t` for a new tab). New module-level functions,
+ :func:`open_new` and :func:`open_new_tab`, were added to support this. The
+ module's :func:`open` function supports an additional feature, an *autoraise*
+ parameter that signals whether to raise the open window when possible. A number
+ of additional browsers were added to the supported list such as Firefox, Opera,
+ Konqueror, and elinks. (Contributed by Oleg Broytmann and Georg Brandl.)
+
+ .. % Patch #754022
+
+* The :mod:`xmlrpclib` module now supports returning :class:`datetime` objects
+ for the XML-RPC date type. Supply ``use_datetime=True`` to the :func:`loads`
+ function or the :class:`Unmarshaller` class to enable this feature. (Contributed
+ by Skip Montanaro.)
+
+ .. % Patch 1120353
+
+* The :mod:`zipfile` module now supports the ZIP64 version of the format,
+ meaning that a .zip archive can now be larger than 4 GiB and can contain
+ individual files larger than 4 GiB. (Contributed by Ronald Oussoren.)
+
+ .. % Patch 1446489
+
+* The :mod:`zlib` module's :class:`Compress` and :class:`Decompress` objects now
+ support a :meth:`copy` method that makes a copy of the object's internal state
+ and returns a new :class:`Compress` or :class:`Decompress` object.
+ (Contributed by Chris AtLee.)
+
+ .. % Patch 1435422
+
+.. % ======================================================================
+
+
+.. _module-ctypes:
+
+The ctypes package
+------------------
+
+The :mod:`ctypes` package, written by Thomas Heller, has been added to the
+standard library. :mod:`ctypes` lets you call arbitrary functions in shared
+libraries or DLLs. Long-time users may remember the :mod:`dl` module, which
+provides functions for loading shared libraries and calling functions in them.
+The :mod:`ctypes` package is much fancier.
+
+To load a shared library or DLL, you must create an instance of the
+:class:`CDLL` class and provide the name or path of the shared library or DLL.
+Once that's done, you can call arbitrary functions by accessing them as
+attributes of the :class:`CDLL` object. ::
+
+ import ctypes
+
+ libc = ctypes.CDLL('libc.so.6')
+ result = libc.printf("Line of output\n")
+
+Type constructors for the various C types are provided: :func:`c_int`,
+:func:`c_float`, :func:`c_double`, :func:`c_char_p` (equivalent to :ctype:`char
+\*`), and so forth. Unlike Python's types, the C versions are all mutable; you
+can assign to their :attr:`value` attribute to change the wrapped value. Python
+integers and strings will be automatically converted to the corresponding C
+types, but for other types you must call the correct type constructor. (And I
+mean *must*; getting it wrong will often result in the interpreter crashing
+with a segmentation fault.)
+
+You shouldn't use :func:`c_char_p` with a Python string when the C function will
+be modifying the memory area, because Python strings are supposed to be
+immutable; breaking this rule will cause puzzling bugs. When you need a
+modifiable memory area, use :func:`create_string_buffer`::
+
+ s = "this is a string"
+ buf = ctypes.create_string_buffer(s)
+ libc.strfry(buf)
+
+C functions are assumed to return integers, but you can set the :attr:`restype`
+attribute of the function object to change this::
+
+ >>> libc.atof('2.71828')
+ -1783957616
+ >>> libc.atof.restype = ctypes.c_double
+ >>> libc.atof('2.71828')
+ 2.71828
+
+:mod:`ctypes` also provides a wrapper for Python's C API as the
+``ctypes.pythonapi`` object. This object does *not* release the global
+interpreter lock before calling a function, because the lock must be held when
+calling into the interpreter's code. There's a :class:`py_object()` type
+constructor that will create a :ctype:`PyObject \*` pointer. A simple usage::
+
+ import ctypes
+
+ d = {}
+ ctypes.pythonapi.PyObject_SetItem(ctypes.py_object(d),
+ ctypes.py_object("abc"), ctypes.py_object(1))
+ # d is now {'abc', 1}.
+
+Don't forget to use :class:`py_object()`; if it's omitted you end up with a
+segmentation fault.
+
+:mod:`ctypes` has been around for a while, but people still write and
+distribution hand-coded extension modules because you can't rely on
+:mod:`ctypes` being present. Perhaps developers will begin to write Python
+wrappers atop a library accessed through :mod:`ctypes` instead of extension
+modules, now that :mod:`ctypes` is included with core Python.
+
+
+.. seealso::
+
+ http://starship.python.net/crew/theller/ctypes/
+ The ctypes web page, with a tutorial, reference, and FAQ.
+
+ The documentation for the :mod:`ctypes` module.
+
+.. % ======================================================================
+
+
+.. _module-etree:
+
+The ElementTree package
+-----------------------
+
+A subset of Fredrik Lundh's ElementTree library for processing XML has been
+added to the standard library as :mod:`xml.etree`. The available modules are
+:mod:`ElementTree`, :mod:`ElementPath`, and :mod:`ElementInclude` from
+ElementTree 1.2.6. The :mod:`cElementTree` accelerator module is also
+included.
+
+The rest of this section will provide a brief overview of using ElementTree.
+Full documentation for ElementTree is available at http://effbot.org/zone
+/element-index.htm.
+
+ElementTree represents an XML document as a tree of element nodes. The text
+content of the document is stored as the :attr:`.text` and :attr:`.tail`
+attributes of (This is one of the major differences between ElementTree and
+the Document Object Model; in the DOM there are many different types of node,
+including :class:`TextNode`.)
+
+The most commonly used parsing function is :func:`parse`, that takes either a
+string (assumed to contain a filename) or a file-like object and returns an
+:class:`ElementTree` instance::
+
+ from xml.etree import ElementTree as ET
+
+ tree = ET.parse('ex-1.xml')
+
+ feed = urllib.urlopen(
+ 'http://planet.python.org/rss10.xml')
+ tree = ET.parse(feed)
+
+Once you have an :class:`ElementTree` instance, you can call its :meth:`getroot`
+method to get the root :class:`Element` node.
+
+There's also an :func:`XML` function that takes a string literal and returns an
+:class:`Element` node (not an :class:`ElementTree`). This function provides a
+tidy way to incorporate XML fragments, approaching the convenience of an XML
+literal::
+
+ svg = ET.XML("""<svg width="10px" version="1.0">
+ </svg>""")
+ svg.set('height', '320px')
+ svg.append(elem1)
+
+Each XML element supports some dictionary-like and some list-like access
+methods. Dictionary-like operations are used to access attribute values, and
+list-like operations are used to access child nodes.
+
++-------------------------------+--------------------------------------------+
+| Operation | Result |
++===============================+============================================+
+| ``elem[n]`` | Returns n'th child element. |
++-------------------------------+--------------------------------------------+
+| ``elem[m:n]`` | Returns list of m'th through n'th child |
+| | elements. |
++-------------------------------+--------------------------------------------+
+| ``len(elem)`` | Returns number of child elements. |
++-------------------------------+--------------------------------------------+
+| ``list(elem)`` | Returns list of child elements. |
++-------------------------------+--------------------------------------------+
+| ``elem.append(elem2)`` | Adds *elem2* as a child. |
++-------------------------------+--------------------------------------------+
+| ``elem.insert(index, elem2)`` | Inserts *elem2* at the specified location. |
++-------------------------------+--------------------------------------------+
+| ``del elem[n]`` | Deletes n'th child element. |
++-------------------------------+--------------------------------------------+
+| ``elem.keys()`` | Returns list of attribute names. |
++-------------------------------+--------------------------------------------+
+| ``elem.get(name)`` | Returns value of attribute *name*. |
++-------------------------------+--------------------------------------------+
+| ``elem.set(name, value)`` | Sets new value for attribute *name*. |
++-------------------------------+--------------------------------------------+
+| ``elem.attrib`` | Retrieves the dictionary containing |
+| | attributes. |
++-------------------------------+--------------------------------------------+
+| ``del elem.attrib[name]`` | Deletes attribute *name*. |
++-------------------------------+--------------------------------------------+
+
+Comments and processing instructions are also represented as :class:`Element`
+nodes. To check if a node is a comment or processing instructions::
+
+ if elem.tag is ET.Comment:
+ ...
+ elif elem.tag is ET.ProcessingInstruction:
+ ...
+
+To generate XML output, you should call the :meth:`ElementTree.write` method.
+Like :func:`parse`, it can take either a string or a file-like object::
+
+ # Encoding is US-ASCII
+ tree.write('output.xml')
+
+ # Encoding is UTF-8
+ f = open('output.xml', 'w')
+ tree.write(f, encoding='utf-8')
+
+(Caution: the default encoding used for output is ASCII. For general XML work,
+where an element's name may contain arbitrary Unicode characters, ASCII isn't a
+very useful encoding because it will raise an exception if an element's name
+contains any characters with values greater than 127. Therefore, it's best to
+specify a different encoding such as UTF-8 that can handle any Unicode
+character.)
+
+This section is only a partial description of the ElementTree interfaces. Please
+read the package's official documentation for more details.
+
+
+.. seealso::
+
+ http://effbot.org/zone/element-index.htm
+ Official documentation for ElementTree.
+
+.. % ======================================================================
+
+
+.. _module-hashlib:
+
+The hashlib package
+-------------------
+
+A new :mod:`hashlib` module, written by Gregory P. Smith, has been added to
+replace the :mod:`md5` and :mod:`sha` modules. :mod:`hashlib` adds support for
+additional secure hashes (SHA-224, SHA-256, SHA-384, and SHA-512). When
+available, the module uses OpenSSL for fast platform optimized implementations
+of algorithms.
+
+The old :mod:`md5` and :mod:`sha` modules still exist as wrappers around hashlib
+to preserve backwards compatibility. The new module's interface is very close
+to that of the old modules, but not identical. The most significant difference
+is that the constructor functions for creating new hashing objects are named
+differently. ::
+
+ # Old versions
+ h = md5.md5()
+ h = md5.new()
+
+ # New version
+ h = hashlib.md5()
+
+ # Old versions
+ h = sha.sha()
+ h = sha.new()
+
+ # New version
+ h = hashlib.sha1()
+
+ # Hash that weren't previously available
+ h = hashlib.sha224()
+ h = hashlib.sha256()
+ h = hashlib.sha384()
+ h = hashlib.sha512()
+
+ # Alternative form
+ h = hashlib.new('md5') # Provide algorithm as a string
+
+Once a hash object has been created, its methods are the same as before:
+:meth:`update(string)` hashes the specified string into the current digest
+state, :meth:`digest` and :meth:`hexdigest` return the digest value as a binary
+string or a string of hex digits, and :meth:`copy` returns a new hashing object
+with the same digest state.
+
+
+.. seealso::
+
+ The documentation for the :mod:`hashlib` module.
+
+.. % ======================================================================
+
+
+.. _module-sqlite:
+
+The sqlite3 package
+-------------------
+
+The pysqlite module (http://www.pysqlite.org), a wrapper for the SQLite embedded
+database, has been added to the standard library under the package name
+:mod:`sqlite3`.
+
+SQLite is a C library that provides a lightweight disk-based database that
+doesn't require a separate server process and allows accessing the database
+using a nonstandard variant of the SQL query language. Some applications can use
+SQLite for internal data storage. It's also possible to prototype an
+application using SQLite and then port the code to a larger database such as
+PostgreSQL or Oracle.
+
+pysqlite was written by Gerhard Häring and provides a SQL interface compliant
+with the DB-API 2.0 specification described by :pep:`249`.
+
+If you're compiling the Python source yourself, note that the source tree
+doesn't include the SQLite code, only the wrapper module. You'll need to have
+the SQLite libraries and headers installed before compiling Python, and the
+build process will compile the module when the necessary headers are available.
+
+To use the module, you must first create a :class:`Connection` object that
+represents the database. Here the data will be stored in the
+:file:`/tmp/example` file::
+
+ conn = sqlite3.connect('/tmp/example')
+
+You can also supply the special name ``:memory:`` to create a database in RAM.
+
+Once you have a :class:`Connection`, you can create a :class:`Cursor` object
+and call its :meth:`execute` method to perform SQL commands::
+
+ c = conn.cursor()
+
+ # Create table
+ c.execute('''create table stocks
+ (date text, trans text, symbol text,
+ qty real, price real)''')
+
+ # Insert a row of data
+ c.execute("""insert into stocks
+ values ('2006-01-05','BUY','RHAT',100,35.14)""")
+
+Usually your SQL operations will need to use values from Python variables. You
+shouldn't assemble your query using Python's string operations because doing so
+is insecure; it makes your program vulnerable to an SQL injection attack.
+
+Instead, use the DB-API's parameter substitution. Put ``?`` as a placeholder
+wherever you want to use a value, and then provide a tuple of values as the
+second argument to the cursor's :meth:`execute` method. (Other database modules
+may use a different placeholder, such as ``%s`` or ``:1``.) For example::
+
+ # Never do this -- insecure!
+ symbol = 'IBM'
+ c.execute("... where symbol = '%s'" % symbol)
+
+ # Do this instead
+ t = (symbol,)
+ c.execute('select * from stocks where symbol=?', t)
+
+ # Larger example
+ for t in (('2006-03-28', 'BUY', 'IBM', 1000, 45.00),
+ ('2006-04-05', 'BUY', 'MSOFT', 1000, 72.00),
+ ('2006-04-06', 'SELL', 'IBM', 500, 53.00),
+ ):
+ c.execute('insert into stocks values (?,?,?,?,?)', t)
+
+To retrieve data after executing a SELECT statement, you can either treat the
+cursor as an iterator, call the cursor's :meth:`fetchone` method to retrieve a
+single matching row, or call :meth:`fetchall` to get a list of the matching
+rows.
+
+This example uses the iterator form::
+
+ >>> c = conn.cursor()
+ >>> c.execute('select * from stocks order by price')
+ >>> for row in c:
+ ... print row
+ ...
+ (u'2006-01-05', u'BUY', u'RHAT', 100, 35.140000000000001)
+ (u'2006-03-28', u'BUY', u'IBM', 1000, 45.0)
+ (u'2006-04-06', u'SELL', u'IBM', 500, 53.0)
+ (u'2006-04-05', u'BUY', u'MSOFT', 1000, 72.0)
+ >>>
+
+For more information about the SQL dialect supported by SQLite, see
+http://www.sqlite.org.
+
+
+.. seealso::
+
+ http://www.pysqlite.org
+ The pysqlite web page.
+
+ http://www.sqlite.org
+ The SQLite web page; the documentation describes the syntax and the available
+ data types for the supported SQL dialect.
+
+ The documentation for the :mod:`sqlite3` module.
+
+ :pep:`249` - Database API Specification 2.0
+ PEP written by Marc-André Lemburg.
+
+.. % ======================================================================
+
+
+.. _module-wsgiref:
+
+The wsgiref package
+-------------------
+
+The Web Server Gateway Interface (WSGI) v1.0 defines a standard interface
+between web servers and Python web applications and is described in :pep:`333`.
+The :mod:`wsgiref` package is a reference implementation of the WSGI
+specification.
+
+.. % XXX should this be in a PEP 333 section instead?
+
+The package includes a basic HTTP server that will run a WSGI application; this
+server is useful for debugging but isn't intended for production use. Setting
+up a server takes only a few lines of code::
+
+ from wsgiref import simple_server
+
+ wsgi_app = ...
+
+ host = ''
+ port = 8000
+ httpd = simple_server.make_server(host, port, wsgi_app)
+ httpd.serve_forever()
+
+.. % XXX discuss structure of WSGI applications?
+.. % XXX provide an example using Django or some other framework?
+
+
+.. seealso::
+
+ http://www.wsgi.org
+ A central web site for WSGI-related resources.
+
+ :pep:`333` - Python Web Server Gateway Interface v1.0
+ PEP written by Phillip J. Eby.
+
+.. % ======================================================================
+
+
+.. _build-api:
+
+Build and C API Changes
+=======================
+
+Changes to Python's build process and to the C API include:
+
+* The Python source tree was converted from CVS to Subversion, in a complex
+ migration procedure that was supervised and flawlessly carried out by Martin von
+ Löwis. The procedure was developed as :pep:`347`.
+
+* Coverity, a company that markets a source code analysis tool called Prevent,
+ provided the results of their examination of the Python source code. The
+ analysis found about 60 bugs that were quickly fixed. Many of the bugs were
+ refcounting problems, often occurring in error-handling code. See
+ http://scan.coverity.com for the statistics.
+
+* The largest change to the C API came from :pep:`353`, which modifies the
+ interpreter to use a :ctype:`Py_ssize_t` type definition instead of
+ :ctype:`int`. See the earlier section :ref:`pep-353` for a discussion of this
+ change.
+
+* The design of the bytecode compiler has changed a great deal, no longer
+ generating bytecode by traversing the parse tree. Instead the parse tree is
+ converted to an abstract syntax tree (or AST), and it is the abstract syntax
+ tree that's traversed to produce the bytecode.
+
+ It's possible for Python code to obtain AST objects by using the
+ :func:`compile` built-in and specifying ``_ast.PyCF_ONLY_AST`` as the value of
+ the *flags* parameter::
+
+ from _ast import PyCF_ONLY_AST
+ ast = compile("""a=0
+ for i in range(10):
+ a += i
+ """, "<string>", 'exec', PyCF_ONLY_AST)
+
+ assignment = ast.body[0]
+ for_loop = ast.body[1]
+
+ No official documentation has been written for the AST code yet, but :pep:`339`
+ discusses the design. To start learning about the code, read the definition of
+ the various AST nodes in :file:`Parser/Python.asdl`. A Python script reads this
+ file and generates a set of C structure definitions in
+ :file:`Include/Python-ast.h`. The :cfunc:`PyParser_ASTFromString` and
+ :cfunc:`PyParser_ASTFromFile`, defined in :file:`Include/pythonrun.h`, take
+ Python source as input and return the root of an AST representing the contents.
+ This AST can then be turned into a code object by :cfunc:`PyAST_Compile`. For
+ more information, read the source code, and then ask questions on python-dev.
+
+ The AST code was developed under Jeremy Hylton's management, and implemented by
+ (in alphabetical order) Brett Cannon, Nick Coghlan, Grant Edwards, John
+ Ehresman, Kurt Kaiser, Neal Norwitz, Tim Peters, Armin Rigo, and Neil
+ Schemenauer, plus the participants in a number of AST sprints at conferences
+ such as PyCon.
+
+ .. % List of names taken from Jeremy's python-dev post at
+ .. % http://mail.python.org/pipermail/python-dev/2005-October/057500.html
+
+* Evan Jones's patch to obmalloc, first described in a talk at PyCon DC 2005,
+ was applied. Python 2.4 allocated small objects in 256K-sized arenas, but never
+ freed arenas. With this patch, Python will free arenas when they're empty. The
+ net effect is that on some platforms, when you allocate many objects, Python's
+ memory usage may actually drop when you delete them and the memory may be
+ returned to the operating system. (Implemented by Evan Jones, and reworked by
+ Tim Peters.)
+
+ Note that this change means extension modules must be more careful when
+ allocating memory. Python's API has many different functions for allocating
+ memory that are grouped into families. For example, :cfunc:`PyMem_Malloc`,
+ :cfunc:`PyMem_Realloc`, and :cfunc:`PyMem_Free` are one family that allocates
+ raw memory, while :cfunc:`PyObject_Malloc`, :cfunc:`PyObject_Realloc`, and
+ :cfunc:`PyObject_Free` are another family that's supposed to be used for
+ creating Python objects.
+
+ Previously these different families all reduced to the platform's
+ :cfunc:`malloc` and :cfunc:`free` functions. This meant it didn't matter if
+ you got things wrong and allocated memory with the :cfunc:`PyMem` function but
+ freed it with the :cfunc:`PyObject` function. With 2.5's changes to obmalloc,
+ these families now do different things and mismatches will probably result in a
+ segfault. You should carefully test your C extension modules with Python 2.5.
+
+* The built-in set types now have an official C API. Call :cfunc:`PySet_New`
+ and :cfunc:`PyFrozenSet_New` to create a new set, :cfunc:`PySet_Add` and
+ :cfunc:`PySet_Discard` to add and remove elements, and :cfunc:`PySet_Contains`
+ and :cfunc:`PySet_Size` to examine the set's state. (Contributed by Raymond
+ Hettinger.)
+
+* C code can now obtain information about the exact revision of the Python
+ interpreter by calling the :cfunc:`Py_GetBuildInfo` function that returns a
+ string of build information like this: ``"trunk:45355:45356M, Apr 13 2006,
+ 07:42:19"``. (Contributed by Barry Warsaw.)
+
+* Two new macros can be used to indicate C functions that are local to the
+ current file so that a faster calling convention can be used.
+ :cfunc:`Py_LOCAL(type)` declares the function as returning a value of the
+ specified *type* and uses a fast-calling qualifier.
+ :cfunc:`Py_LOCAL_INLINE(type)` does the same thing and also requests the
+ function be inlined. If :cfunc:`PY_LOCAL_AGGRESSIVE` is defined before
+ :file:`python.h` is included, a set of more aggressive optimizations are enabled
+ for the module; you should benchmark the results to find out if these
+ optimizations actually make the code faster. (Contributed by Fredrik Lundh at
+ the NeedForSpeed sprint.)
+
+* :cfunc:`PyErr_NewException(name, base, dict)` can now accept a tuple of base
+ classes as its *base* argument. (Contributed by Georg Brandl.)
+
+* The :cfunc:`PyErr_Warn` function for issuing warnings is now deprecated in
+ favour of :cfunc:`PyErr_WarnEx(category, message, stacklevel)` which lets you
+ specify the number of stack frames separating this function and the caller. A
+ *stacklevel* of 1 is the function calling :cfunc:`PyErr_WarnEx`, 2 is the
+ function above that, and so forth. (Added by Neal Norwitz.)
+
+* The CPython interpreter is still written in C, but the code can now be
+ compiled with a C++ compiler without errors. (Implemented by Anthony Baxter,
+ Martin von Löwis, Skip Montanaro.)
+
+* The :cfunc:`PyRange_New` function was removed. It was never documented, never
+ used in the core code, and had dangerously lax error checking. In the unlikely
+ case that your extensions were using it, you can replace it by something like
+ the following::
+
+ range = PyObject_CallFunction((PyObject*) &PyRange_Type, "lll",
+ start, stop, step);
+
+.. % ======================================================================
+
+
+.. _ports:
+
+Port-Specific Changes
+---------------------
+
+* MacOS X (10.3 and higher): dynamic loading of modules now uses the
+ :cfunc:`dlopen` function instead of MacOS-specific functions.
+
+* MacOS X: a :option:`--enable-universalsdk` switch was added to the
+ :program:`configure` script that compiles the interpreter as a universal binary
+ able to run on both PowerPC and Intel processors. (Contributed by Ronald
+ Oussoren.)
+
+* Windows: :file:`.dll` is no longer supported as a filename extension for
+ extension modules. :file:`.pyd` is now the only filename extension that will be
+ searched for.
+
+.. % ======================================================================
+
+
+.. _porting:
+
+Porting to Python 2.5
+=====================
+
+This section lists previously described changes that may require changes to your
+code:
+
+* ASCII is now the default encoding for modules. It's now a syntax error if a
+ module contains string literals with 8-bit characters but doesn't have an
+ encoding declaration. In Python 2.4 this triggered a warning, not a syntax
+ error.
+
+* Previously, the :attr:`gi_frame` attribute of a generator was always a frame
+ object. Because of the :pep:`342` changes described in section :ref:`pep-342`,
+ it's now possible for :attr:`gi_frame` to be ``None``.
+
+* A new warning, :class:`UnicodeWarning`, is triggered when you attempt to
+ compare a Unicode string and an 8-bit string that can't be converted to Unicode
+ using the default ASCII encoding. Previously such comparisons would raise a
+ :class:`UnicodeDecodeError` exception.
+
+* Library: the :mod:`csv` module is now stricter about multi-line quoted fields.
+ If your files contain newlines embedded within fields, the input should be split
+ into lines in a manner which preserves the newline characters.
+
+* Library: the :mod:`locale` module's :func:`format` function's would
+ previously accept any string as long as no more than one %char specifier
+ appeared. In Python 2.5, the argument must be exactly one %char specifier with
+ no surrounding text.
+
+* Library: The :mod:`pickle` and :mod:`cPickle` modules no longer accept a
+ return value of ``None`` from the :meth:`__reduce__` method; the method must
+ return a tuple of arguments instead. The modules also no longer accept the
+ deprecated *bin* keyword parameter.
+
+* Library: The :mod:`SimpleXMLRPCServer` and :mod:`DocXMLRPCServer` classes now
+ have a :attr:`rpc_paths` attribute that constrains XML-RPC operations to a
+ limited set of URL paths; the default is to allow only ``'/'`` and ``'/RPC2'``.
+ Setting :attr:`rpc_paths` to ``None`` or an empty tuple disables this path
+ checking.
+
+* C API: Many functions now use :ctype:`Py_ssize_t` instead of :ctype:`int` to
+ allow processing more data on 64-bit machines. Extension code may need to make
+ the same change to avoid warnings and to support 64-bit machines. See the
+ earlier section :ref:`pep-353` for a discussion of this change.
+
+* C API: The obmalloc changes mean that you must be careful to not mix usage
+ of the :cfunc:`PyMem_\*` and :cfunc:`PyObject_\*` families of functions. Memory
+ allocated with one family's :cfunc:`\*_Malloc` must be freed with the
+ corresponding family's :cfunc:`\*_Free` function.
+
+.. % ======================================================================
+
+
+.. _acks:
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: Georg Brandl,
+Nick Coghlan, Phillip J. Eby, Lars Gustäbel, Raymond Hettinger, Ralf W. Grosse-
+Kunstleve, Kent Johnson, Iain Lowe, Martin von Löwis, Fredrik Lundh, Andrew
+McNamara, Skip Montanaro, Gustavo Niemeyer, Paul Prescod, James Pryor, Mike
+Rovner, Scott Weikart, Barry Warsaw, Thomas Wouters.
+
diff --git a/Doc/whatsnew/2.6.rst b/Doc/whatsnew/2.6.rst
new file mode 100644
index 0000000000..b0e731a6de
--- /dev/null
+++ b/Doc/whatsnew/2.6.rst
@@ -0,0 +1,236 @@
+****************************
+ What's New in Python 2.6
+****************************
+
+:Author: A.M. Kuchling
+:Release: |release|
+:Date: |today|
+
+.. % $Id: whatsnew26.tex 55963 2007-06-13 18:07:49Z guido.van.rossum $
+.. % Rules for maintenance:
+.. %
+.. % * Anyone can add text to this document. Do not spend very much time
+.. % on the wording of your changes, because your text will probably
+.. % get rewritten to some degree.
+.. %
+.. % * The maintainer will go through Misc/NEWS periodically and add
+.. % changes; it's therefore more important to add your changes to
+.. % Misc/NEWS than to this file.
+.. %
+.. % * This is not a complete list of every single change; completeness
+.. % is the purpose of Misc/NEWS. Some changes I consider too small
+.. % or esoteric to include. If such a change is added to the text,
+.. % I'll just remove it. (This is another reason you shouldn't spend
+.. % too much time on writing your addition.)
+.. %
+.. % * If you want to draw your new text to the attention of the
+.. % maintainer, add 'XXX' to the beginning of the paragraph or
+.. % section.
+.. %
+.. % * It's OK to just add a fragmentary note about a change. For
+.. % example: "XXX Describe the transmogrify() function added to the
+.. % socket module." The maintainer will research the change and
+.. % write the necessary text.
+.. %
+.. % * You can comment out your additions if you like, but it's not
+.. % necessary (especially when a final release is some months away).
+.. %
+.. % * Credit the author of a patch or bugfix. Just the name is
+.. % sufficient; the e-mail address isn't necessary.
+.. %
+.. % * It's helpful to add the bug/patch number as a comment:
+.. %
+.. % % Patch 12345
+.. % XXX Describe the transmogrify() function added to the socket
+.. % module.
+.. % (Contributed by P.Y. Developer.)
+.. %
+.. % This saves the maintainer the effort of going through the SVN log
+.. % when researching a change.
+
+This article explains the new features in Python 2.6. No release date for
+Python 2.6 has been set; it will probably be released in mid 2008.
+
+This article doesn't attempt to provide a complete specification of the new
+features, but instead provides a convenient overview. For full details, you
+should refer to the documentation for Python 2.6. If you want to understand the
+complete implementation and design rationale, refer to the PEP for a particular
+new feature.
+
+.. % Compare with previous release in 2 - 3 sentences here.
+.. % add hyperlink when the documentation becomes available online.
+
+.. % ======================================================================
+.. % Large, PEP-level features and changes should be described here.
+.. % Should there be a new section here for 3k migration?
+.. % Or perhaps a more general section describing module changes/deprecation?
+.. % sets module deprecated
+.. % ======================================================================
+
+
+Other Language Changes
+======================
+
+Here are all of the changes that Python 2.6 makes to the core Python language.
+
+* An obscure change: when you use the the :func:`locals` function inside a
+ :keyword:`class` statement, the resulting dictionary no longer returns free
+ variables. (Free variables, in this case, are variables referred to in the
+ :keyword:`class` statement that aren't attributes of the class.)
+
+.. % ======================================================================
+
+
+Optimizations
+-------------
+
+* Internally, a bit is now set in type objects to indicate some of the standard
+ built-in types. This speeds up checking if an object is a subclass of one of
+ these types. (Contributed by Neal Norwitz.)
+
+The net result of the 2.6 optimizations is that Python 2.6 runs the pystone
+benchmark around XX% faster than Python 2.5.
+
+.. % ======================================================================
+
+
+New, Improved, and Deprecated Modules
+=====================================
+
+As usual, Python's standard library received a number of enhancements and bug
+fixes. Here's a partial list of the most notable changes, sorted alphabetically
+by module name. Consult the :file:`Misc/NEWS` file in the source tree for a more
+complete list of changes, or look through the CVS logs for all the details.
+
+* A new data type in the :mod:`collections` module: :class:`NamedTuple(typename,
+ fieldnames)` is a factory function that creates subclasses of the standard tuple
+ whose fields are accessible by name as well as index. For example::
+
+ var_type = collections.NamedTuple('variable',
+ 'id name type size')
+ var = var_type(1, 'frequency', 'int', 4)
+
+ print var[0], var.id # Equivalent
+ print var[2], var.type # Equivalent
+
+ (Contributed by Raymond Hettinger.)
+
+* A new method in the :mod:`curses` module: for a window, :meth:`chgat` changes
+ the display characters for a certain number of characters on a single line. ::
+
+ # Boldface text starting at y=0,x=21
+ # and affecting the rest of the line.
+ stdscr.chgat(0,21, curses.A_BOLD)
+
+ (Contributed by Fabian Kreutz.)
+
+* The :func:`glob.glob` function can now return Unicode filenames if
+ a Unicode path was used and Unicode filenames are matched within the directory.
+
+ .. % Patch #1001604
+
+* The :mod:`gopherlib` module has been removed.
+
+* A new function in the :mod:`heapq` module: ``merge(iter1, iter2, ...)``
+ takes any number of iterables that return data *in sorted order*, and returns
+ a new iterator that returns the contents of all the iterators, also in sorted
+ order. For example::
+
+ heapq.merge([1, 3, 5, 9], [2, 8, 16]) ->
+ [1, 2, 3, 5, 8, 9, 16]
+
+ (Contributed by Raymond Hettinger.)
+
+* A new function in the :mod:`itertools` module: ``izip_longest(iter1, iter2,
+ ...[, fillvalue])`` makes tuples from each of the elements; if some of the
+ iterables are shorter than others, the missing values are set to *fillvalue*.
+ For example::
+
+ itertools.izip_longest([1,2,3], [1,2,3,4,5]) ->
+ [(1, 1), (2, 2), (3, 3), (None, 4), (None, 5)]
+
+ (Contributed by Raymond Hettinger.)
+
+* The :mod:`macfs` module has been removed. This in turn required the
+ :func:`macostools.touched` function to be removed because it depended on the
+ :mod:`macfs` module.
+
+ .. % Patch #1490190
+
+* New functions in the :mod:`posix` module: :func:`chflags` and :func:`lchflags`
+ are wrappers for the corresponding system calls (where they're available).
+ Constants for the flag values are defined in the :mod:`stat` module; some
+ possible values include :const:`UF_IMMUTABLE` to signal the file may not be
+ changed and :const:`UF_APPEND` to indicate that data can only be appended to the
+ file. (Contributed by M. Levinson.)
+
+* The :mod:`rgbimg` module has been removed.
+
+* The :mod:`smtplib` module now supports SMTP over SSL thanks to the addition
+ of the :class:`SMTP_SSL` class. This class supports an interface identical to
+ the existing :class:`SMTP` class. (Contributed by Monty Taylor.)
+
+* The :mod:`test.test_support` module now contains a :func:`EnvironmentVarGuard`
+ context manager that supports temporarily changing environment variables and
+ automatically restores them to their old values. (Contributed by Brett Cannon.)
+
+.. % ======================================================================
+.. % whole new modules get described in \subsections here
+
+.. % ======================================================================
+
+
+Build and C API Changes
+=======================
+
+Changes to Python's build process and to the C API include:
+
+* Detailed changes are listed here.
+
+.. % ======================================================================
+
+
+Port-Specific Changes
+---------------------
+
+Platform-specific changes go here.
+
+.. % ======================================================================
+
+
+.. _section-other:
+
+Other Changes and Fixes
+=======================
+
+As usual, there were a bunch of other improvements and bugfixes scattered
+throughout the source tree. A search through the change logs finds there were
+XXX patches applied and YYY bugs fixed between Python 2.5 and 2.6. Both figures
+are likely to be underestimates.
+
+Some of the more notable changes are:
+
+* Details go here.
+
+.. % ======================================================================
+
+
+Porting to Python 2.6
+=====================
+
+This section lists previously described changes that may require changes to your
+code:
+
+* Everything is all in the details!
+
+.. % ======================================================================
+
+
+.. _acks:
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: .
+
diff --git a/Doc/whatsnew/3.0.rst b/Doc/whatsnew/3.0.rst
new file mode 100644
index 0000000000..ac82317128
--- /dev/null
+++ b/Doc/whatsnew/3.0.rst
@@ -0,0 +1,161 @@
+****************************
+ What's New in Python 3.0
+****************************
+
+:Author: A.M. Kuchling
+
+.. |release| replace:: 0.0
+
+.. % $Id: whatsnew26.tex 55506 2007-05-22 07:43:29Z neal.norwitz $
+.. % Rules for maintenance:
+.. %
+.. % * Anyone can add text to this document. Do not spend very much time
+.. % on the wording of your changes, because your text will probably
+.. % get rewritten to some degree.
+.. %
+.. % * The maintainer will go through Misc/NEWS periodically and add
+.. % changes; it's therefore more important to add your changes to
+.. % Misc/NEWS than to this file.
+.. %
+.. % * This is not a complete list of every single change; completeness
+.. % is the purpose of Misc/NEWS. Some changes I consider too small
+.. % or esoteric to include. If such a change is added to the text,
+.. % I'll just remove it. (This is another reason you shouldn't spend
+.. % too much time on writing your addition.)
+.. %
+.. % * If you want to draw your new text to the attention of the
+.. % maintainer, add 'XXX' to the beginning of the paragraph or
+.. % section.
+.. %
+.. % * It's OK to just add a fragmentary note about a change. For
+.. % example: "XXX Describe the transmogrify() function added to the
+.. % socket module." The maintainer will research the change and
+.. % write the necessary text.
+.. %
+.. % * You can comment out your additions if you like, but it's not
+.. % necessary (especially when a final release is some months away).
+.. %
+.. % * Credit the author of a patch or bugfix. Just the name is
+.. % sufficient; the e-mail address isn't necessary.
+.. %
+.. % * It's helpful to add the bug/patch number as a comment:
+.. %
+.. % % Patch 12345
+.. % XXX Describe the transmogrify() function added to the socket
+.. % module.
+.. % (Contributed by P.Y. Developer.)
+.. %
+.. % This saves the maintainer the effort of going through the SVN log
+.. % when researching a change.
+
+This article explains the new features in Python 3.0. No release date for
+Python 3.0 has been set; it will probably be released in mid 2008.
+
+This article doesn't attempt to provide a complete specification of the new
+features, but instead provides a convenient overview. For full details, you
+should refer to the documentation for Python 3.0. If you want to understand the
+complete implementation and design rationale, refer to the PEP for a particular
+new feature.
+
+.. % Compare with previous release in 2 - 3 sentences here.
+.. % add hyperlink when the documentation becomes available online.
+
+.. % ======================================================================
+.. % Large, PEP-level features and changes should be described here.
+.. % Should there be a new section here for 3k migration?
+.. % Or perhaps a more general section describing module changes/deprecation?
+.. % sets module deprecated
+.. % ======================================================================
+
+
+Other Language Changes
+======================
+
+Here are all of the changes that Python 2.6 makes to the core Python language.
+
+* Detailed changes are listed here.
+
+.. % ======================================================================
+
+
+Optimizations
+-------------
+
+* Detailed changes are listed here.
+
+The net result of the 3.0 optimizations is that Python 3.0 runs the pystone
+benchmark around XX% slower than Python 2.6.
+
+.. % ======================================================================
+
+
+New, Improved, and Deprecated Modules
+=====================================
+
+As usual, Python's standard library received a number of enhancements and bug
+fixes. Here's a partial list of the most notable changes, sorted alphabetically
+by module name. Consult the :file:`Misc/NEWS` file in the source tree for a more
+complete list of changes, or look through the CVS logs for all the details.
+
+* Detailed changes are listed here.
+
+.. % ======================================================================
+.. % whole new modules get described in \subsections here
+
+.. % ======================================================================
+
+
+Build and C API Changes
+=======================
+
+Changes to Python's build process and to the C API include:
+
+* Detailed changes are listed here.
+
+.. % ======================================================================
+
+
+Port-Specific Changes
+---------------------
+
+Platform-specific changes go here.
+
+.. % ======================================================================
+
+
+.. _section-other:
+
+Other Changes and Fixes
+=======================
+
+As usual, there were a bunch of other improvements and bugfixes scattered
+throughout the source tree. A search through the change logs finds there were
+XXX patches applied and YYY bugs fixed between Python 2.6 and 3.0. Both figures
+are likely to be underestimates.
+
+Some of the more notable changes are:
+
+* Details go here.
+
+.. % ======================================================================
+
+
+Porting to Python 3.0
+=====================
+
+This section lists previously described changes that may require changes to your
+code:
+
+* Everything is all in the details!
+
+.. % ======================================================================
+
+
+.. _acks:
+
+Acknowledgements
+================
+
+The author would like to thank the following people for offering suggestions,
+corrections and assistance with various drafts of this article: .
+