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| author | Éric Araujo <merwok@netwok.org> | 2011-05-02 13:33:14 +0200 |
|---|---|---|
| committer | Éric Araujo <merwok@netwok.org> | 2011-05-02 13:33:14 +0200 |
| commit | 779095cbde27e5ebb5add133635975ed37bc0007 (patch) | |
| tree | 00dcfb8500cf4220f85f60bb68675d7cb3c1c716 /Doc | |
| parent | a4574f0d36898725cc1475c15115fbc3c570c098 (diff) | |
| parent | f2cd4f776ac2b07d288df651a9ee45773d67c74c (diff) | |
| download | cpython-779095cbde27e5ebb5add133635975ed37bc0007.tar.gz | |
Merge 3.2
Diffstat (limited to 'Doc')
65 files changed, 2239 insertions, 548 deletions
diff --git a/Doc/ACKS.txt b/Doc/ACKS.txt index 7f67d36cbb..755f6476ce 100644 --- a/Doc/ACKS.txt +++ b/Doc/ACKS.txt @@ -202,6 +202,7 @@ docs@python.org), and we'll be glad to correct the problem. * Jim Tittsler * David Turner * Ville Vainio + * Nadeem Vawda * Martijn Vries * Charles G. Waldman * Greg Ward diff --git a/Doc/bugs.rst b/Doc/bugs.rst index a9a48c7858..3785ccb72b 100644 --- a/Doc/bugs.rst +++ b/Doc/bugs.rst @@ -57,12 +57,14 @@ 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. See http://www.python.org/dev/workflow/ for a detailed -description of the issue workflow. +taken on the bug. .. seealso:: + `Python Developer's Guide <http://docs.python.org/devguide/>`_ + Detailed description of the issue workflow and developers tools. + `How to Report Bugs Effectively <http://www.chiark.greenend.org.uk/~sgtatham/bugs.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. diff --git a/Doc/c-api/import.rst b/Doc/c-api/import.rst index cf48363e10..b168751199 100644 --- a/Doc/c-api/import.rst +++ b/Doc/c-api/import.rst @@ -57,7 +57,7 @@ Importing Modules :c:func:`PyImport_ImportModule`. -.. c:function:: PyObject* PyImport_ImportModuleLevel(char *name, PyObject *globals, PyObject *locals, PyObject *fromlist, int level) +.. c:function:: PyObject* PyImport_ImportModuleLevelObject(PyObject *name, PyObject *globals, PyObject *locals, PyObject *fromlist, int level) Import a module. This is best described by referring to the built-in Python function :func:`__import__`, as the standard :func:`__import__` function calls @@ -68,6 +68,13 @@ Importing Modules the return value when a submodule of a package was requested is normally the top-level package, unless a non-empty *fromlist* was given. + .. versionadded:: 3.3 + + +.. c:function:: PyObject* PyImport_ImportModuleLevel(char *name, PyObject *globals, PyObject *locals, PyObject *fromlist, int level) + + Similar to :c:func:`PyImport_ImportModuleLevelObject`, but the name is an + UTF-8 encoded string instead of a Unicode object. .. c:function:: PyObject* PyImport_Import(PyObject *name) @@ -86,7 +93,7 @@ Importing Modules an exception set on failure (the module still exists in this case). -.. c:function:: PyObject* PyImport_AddModule(const char *name) +.. c:function:: PyObject* PyImport_AddModuleObject(PyObject *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 @@ -100,6 +107,14 @@ Importing Modules 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. + .. versionadded:: 3.3 + + +.. c:function:: PyObject* PyImport_AddModule(const char *name) + + Similar to :c:func:`PyImport_AddModuleObject`, but the name is a UTF-8 + encoded string instead of a Unicode object. + .. c:function:: PyObject* PyImport_ExecCodeModule(char *name, PyObject *co) @@ -136,14 +151,23 @@ Importing Modules See also :c:func:`PyImport_ExecCodeModuleWithPathnames`. -.. c:function:: PyObject* PyImport_ExecCodeModuleWithPathnames(char *name, PyObject *co, char *pathname, char *cpathname) +.. c:function:: PyObject* PyImport_ExecCodeModuleObject(PyObject *name, PyObject *co, PyObject *pathname, PyObject *cpathname) Like :c:func:`PyImport_ExecCodeModuleEx`, but the :attr:`__cached__` attribute of the module object is set to *cpathname* if it is non-``NULL``. Of the three functions, this is the preferred one to use. + .. versionadded:: 3.3 + + +.. c:function:: PyObject* PyImport_ExecCodeModuleWithPathnames(char *name, PyObject *co, char *pathname, char *cpathname) + + Like :c:func:`PyImport_ExecCodeModuleObject`, but *name*, *pathname* and + *cpathname* are UTF-8 encoded strings. + .. versionadded:: 3.2 + .. c:function:: long PyImport_GetMagicNumber() Return the magic number for Python bytecode files (a.k.a. :file:`.pyc` and @@ -200,7 +224,7 @@ Importing Modules For internal use only. -.. c:function:: int PyImport_ImportFrozenModule(char *name) +.. c:function:: int PyImport_ImportFrozenModuleObject(PyObject *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 @@ -208,6 +232,14 @@ Importing Modules :c:func:`PyImport_ImportModule`. (Note the misnomer --- this function would reload the module if it was already imported.) + .. versionadded:: 3.3 + + +.. c:function:: int PyImport_ImportFrozenModule(char *name) + + Similar to :c:func:`PyImport_ImportFrozenModuleObject`, but the name is a + UTF-8 encoded string instead of a Unicode object. + .. c:type:: struct _frozen @@ -247,13 +279,13 @@ Importing Modules 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 :c:func:`PyImport_ExtendInittab` to provide - additional built-in modules. The structure is defined in - :file:`Include/import.h` as:: + into the interpreter. The name is an ASCII encoded string. Programs which + embed Python may use an array of these structures in conjunction with + :c:func:`PyImport_ExtendInittab` to provide additional built-in modules. + The structure is defined in :file:`Include/import.h` as:: struct _inittab { - char *name; + char *name; /* ASCII encoded string */ PyObject* (*initfunc)(void); }; diff --git a/Doc/c-api/module.rst b/Doc/c-api/module.rst index ffd68e3084..b97c08d0bb 100644 --- a/Doc/c-api/module.rst +++ b/Doc/c-api/module.rst @@ -29,7 +29,7 @@ There are only a few functions special to module objects. :c:data:`PyModule_Type`. -.. c:function:: PyObject* PyModule_New(const char *name) +.. c:function:: PyObject* PyModule_NewObject(PyObject *name) .. index:: single: __name__ (module attribute) @@ -40,6 +40,14 @@ There are only a few functions special to module objects. Only the module's :attr:`__doc__` and :attr:`__name__` attributes are filled in; the caller is responsible for providing a :attr:`__file__` attribute. + .. versionadded:: 3.3 + + +.. c:function:: PyObject* PyModule_New(const char *name) + + Similar to :c:func:`PyImport_NewObject`, but the name is an UTF-8 encoded + string instead of a Unicode object. + .. c:function:: PyObject* PyModule_GetDict(PyObject *module) @@ -52,7 +60,7 @@ There are only a few functions special to module objects. manipulate a module's :attr:`__dict__`. -.. c:function:: char* PyModule_GetName(PyObject *module) +.. c:function:: PyObject* PyModule_GetNameObject(PyObject *module) .. index:: single: __name__ (module attribute) @@ -61,15 +69,13 @@ There are only a few functions special to module objects. 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. + .. versionadded:: 3.3 -.. c:function:: char* PyModule_GetFilename(PyObject *module) - Similar to :c:func:`PyModule_GetFilenameObject` but return the filename - encoded to 'utf-8'. +.. c:function:: char* PyModule_GetName(PyObject *module) - .. deprecated:: 3.2 - :c:func:`PyModule_GetFilename` raises :c:type:`UnicodeEncodeError` on - unencodable filenames, use :c:func:`PyModule_GetFilenameObject` instead. + Similar to :c:func:`PyModule_GetNameObject` but return the name encoded to + ``'utf-8'``. .. c:function:: PyObject* PyModule_GetFilenameObject(PyObject *module) @@ -86,6 +92,16 @@ There are only a few functions special to module objects. .. versionadded:: 3.2 +.. c:function:: char* PyModule_GetFilename(PyObject *module) + + Similar to :c:func:`PyModule_GetFilenameObject` but return the filename + encoded to 'utf-8'. + + .. deprecated:: 3.2 + :c:func:`PyModule_GetFilename` raises :c:type:`UnicodeEncodeError` on + unencodable filenames, use :c:func:`PyModule_GetFilenameObject` instead. + + .. c:function:: void* PyModule_GetState(PyObject *module) Return the "state" of the module, that is, a pointer to the block of memory diff --git a/Doc/c-api/unicode.rst b/Doc/c-api/unicode.rst index f48eb73bfd..a69757be0d 100644 --- a/Doc/c-api/unicode.rst +++ b/Doc/c-api/unicode.rst @@ -260,18 +260,27 @@ APIs: | :attr:`%ld` | long | Exactly equivalent to | | | | ``printf("%ld")``. | +-------------------+---------------------+--------------------------------+ + | :attr:`%li` | long | Exactly equivalent to | + | | | ``printf("%li")``. | + +-------------------+---------------------+--------------------------------+ | :attr:`%lu` | unsigned long | Exactly equivalent to | | | | ``printf("%lu")``. | +-------------------+---------------------+--------------------------------+ | :attr:`%lld` | long long | Exactly equivalent to | | | | ``printf("%lld")``. | +-------------------+---------------------+--------------------------------+ + | :attr:`%lli` | long long | Exactly equivalent to | + | | | ``printf("%lli")``. | + +-------------------+---------------------+--------------------------------+ | :attr:`%llu` | unsigned long long | Exactly equivalent to | | | | ``printf("%llu")``. | +-------------------+---------------------+--------------------------------+ | :attr:`%zd` | Py_ssize_t | Exactly equivalent to | | | | ``printf("%zd")``. | +-------------------+---------------------+--------------------------------+ + | :attr:`%zi` | Py_ssize_t | Exactly equivalent to | + | | | ``printf("%zi")``. | + +-------------------+---------------------+--------------------------------+ | :attr:`%zu` | size_t | Exactly equivalent to | | | | ``printf("%zu")``. | +-------------------+---------------------+--------------------------------+ @@ -322,6 +331,9 @@ APIs: .. versionchanged:: 3.2 Support for ``"%lld"`` and ``"%llu"`` added. + .. versionchanged:: 3.3 + Support for ``"%li"``, ``"%lli"`` and ``"%zi"`` added. + .. c:function:: PyObject* PyUnicode_FromFormatV(const char *format, va_list vargs) diff --git a/Doc/documenting/style.rst b/Doc/documenting/style.rst index d0557119fb..9baab12785 100644 --- a/Doc/documenting/style.rst +++ b/Doc/documenting/style.rst @@ -14,9 +14,10 @@ document. Use of whitespace ----------------- -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. +All reST files use an indentation of 3 spaces; no tabs are allowed. The +maximum line length is 80 characters for normal text, but tables, deeply +indented code samples and long links may extend beyond that. Code example +bodies should use normal Python 4-space indentation. Make generous use of blank lines where applicable; they help grouping things together. diff --git a/Doc/faq/general.rst b/Doc/faq/general.rst index 111e3123db..21a5ee5104 100644 --- a/Doc/faq/general.rst +++ b/Doc/faq/general.rst @@ -166,7 +166,7 @@ and run out of the box on most UNIX platforms. .. XXX update link once the dev faq is relocated -Consult the `Developer FAQ <http://www.python.org/dev/faq/>`__ for more +Consult the `Developer FAQ <http://docs.python.org/devguide/faq>`__ for more information on getting the source code and compiling it. @@ -224,7 +224,7 @@ news is available. .. XXX update link once the dev faq is relocated You can also access the development version of Python through Subversion. See -http://www.python.org/dev/faq/ for details. +http://docs.python.org/devguide/faq for details. How do I submit bug reports and patches for Python? @@ -242,7 +242,7 @@ report bugs to Python, you can obtain your Roundup password through Roundup's .. XXX adapt link to dev guide For more information on how Python is developed, consult `the Python Developer's -Guide <http://python.org/dev/>`_. +Guide <http://docs.python.org/devguide/>`_. Are there any published articles about Python that I can reference? diff --git a/Doc/glossary.rst b/Doc/glossary.rst index ec8af62553..4e425c35b7 100644 --- a/Doc/glossary.rst +++ b/Doc/glossary.rst @@ -580,6 +580,14 @@ Glossary an :term:`expression` or a one of several constructs with a keyword, such as :keyword:`if`, :keyword:`while` or :keyword:`for`. + struct sequence + A tuple with named elements. Struct sequences expose an interface similiar + to :term:`named tuple` in that elements can either be accessed either by + index or as an attribute. However, they do not have any of the named tuple + methods like :meth:`~collections.somenamedtuple._make` or + :meth:`~collections.somenamedtuple._asdict`. Examples of struct sequences + include :data:`sys.float_info` and the return value of :func:`os.stat`. + triple-quoted string A string which is bound by three instances of either a quotation mark (") or an apostrophe ('). While they don't provide any functionality diff --git a/Doc/library/_thread.rst b/Doc/library/_thread.rst index 369e9cd01e..e7e7504c42 100644 --- a/Doc/library/_thread.rst +++ b/Doc/library/_thread.rst @@ -35,6 +35,9 @@ It defines the following constants and functions: Raised on thread-specific errors. + .. versionchanged:: 3.3 + This is now a synonym of the built-in :exc:`RuntimeError`. + .. data:: LockType diff --git a/Doc/library/abc.rst b/Doc/library/abc.rst index 9fadbd234e..2eced4541b 100644 --- a/Doc/library/abc.rst +++ b/Doc/library/abc.rst @@ -55,6 +55,9 @@ This module provides the following class: assert issubclass(tuple, MyABC) assert isinstance((), MyABC) + .. versionchanged:: 3.3 + Returns the registered subclass, to allow usage as a class decorator. + You can also override this method in an abstract base class: .. method:: __subclasshook__(subclass) diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst index 61e1786b01..a2bceae15c 100644 --- a/Doc/library/argparse.rst +++ b/Doc/library/argparse.rst @@ -362,16 +362,16 @@ formatter_class ^^^^^^^^^^^^^^^ :class:`ArgumentParser` objects allow the help formatting to be customized by -specifying an alternate formatting class. Currently, there are three such +specifying an alternate formatting class. Currently, there are four such classes: .. class:: RawDescriptionHelpFormatter RawTextHelpFormatter ArgumentDefaultsHelpFormatter + MetavarTypeHelpFormatter -The first two allow more control over how textual descriptions are displayed, -while the last automatically adds information about argument default values. - +:class:`RawDescriptionHelpFormatter` and :class:`RawTextHelpFormatter` give +more control over how textual descriptions are displayed. By default, :class:`ArgumentParser` objects line-wrap the description_ and epilog_ texts in command-line help messages:: @@ -395,7 +395,7 @@ epilog_ texts in command-line help messages:: likewise for this epilog whose whitespace will be cleaned up and whose words will be wrapped across a couple lines -Passing :class:`~argparse.RawDescriptionHelpFormatter` as ``formatter_class=`` +Passing :class:`RawDescriptionHelpFormatter` as ``formatter_class=`` indicates that description_ and epilog_ are already correctly formatted and should not be line-wrapped:: @@ -421,11 +421,11 @@ should not be line-wrapped:: optional arguments: -h, --help show this help message and exit -:class:`RawTextHelpFormatter` maintains whitespace for all sorts of help text +:class:`RawTextHelpFormatter` maintains whitespace for all sorts of help text, including argument descriptions. -The other formatter class available, :class:`ArgumentDefaultsHelpFormatter`, -will add information about the default value of each of the arguments:: +:class:`ArgumentDefaultsHelpFormatter` automatically adds information about +default values to each of the argument help messages:: >>> parser = argparse.ArgumentParser( ... prog='PROG', @@ -442,6 +442,25 @@ will add information about the default value of each of the arguments:: -h, --help show this help message and exit --foo FOO FOO! (default: 42) +:class:`MetavarTypeHelpFormatter` uses the name of the type_ argument for each +argument as as the display name for its values (rather than using the dest_ +as the regular formatter does):: + + >>> parser = argparse.ArgumentParser( + ... prog='PROG', + ... formatter_class=argparse.MetavarTypeHelpFormatter) + >>> parser.add_argument('--foo', type=int) + >>> parser.add_argument('bar', type=float) + >>> parser.print_help() + usage: PROG [-h] [--foo int] float + + positional arguments: + float + + optional arguments: + -h, --help show this help message and exit + --foo int + conflict_handler ^^^^^^^^^^^^^^^^ diff --git a/Doc/library/ast.rst b/Doc/library/ast.rst index e2c0b6d17d..85081be399 100644 --- a/Doc/library/ast.rst +++ b/Doc/library/ast.rst @@ -96,8 +96,8 @@ Node classes Abstract Grammar ---------------- -The module defines a string constant ``__version__`` which is the decimal -Subversion revision number of the file shown below. +The module defines a string constant ``__version__`` which is the Mercurial +revision of the file shown below. The abstract grammar is currently defined as follows: diff --git a/Doc/library/asyncore.rst b/Doc/library/asyncore.rst index 5f95d41161..31c1aa154f 100644 --- a/Doc/library/asyncore.rst +++ b/Doc/library/asyncore.rst @@ -184,12 +184,14 @@ any that have been added to the map during asynchronous service) is closed. Most of these are nearly identical to their socket partners. - .. method:: create_socket(family, type) + .. method:: create_socket(family=socket.AF_INET, type=socket.SOCK_STREAM) 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. + .. versionchanged:: 3.3 family and type arguments can be omitted. + .. method:: connect(address) @@ -280,7 +282,7 @@ implement its socket handling:: def __init__(self, host, path): asyncore.dispatcher.__init__(self) - self.create_socket(socket.AF_INET, socket.SOCK_STREAM) + self.create_socket() self.connect( (host, 80) ) self.buffer = bytes('GET %s HTTP/1.0\r\nHost: %s\r\n\r\n' % (path, host), 'ascii') @@ -327,7 +329,7 @@ connections and dispatches the incoming connections to a handler:: def __init__(self, host, port): asyncore.dispatcher.__init__(self) - self.create_socket(socket.AF_INET, socket.SOCK_STREAM) + self.create_socket() self.set_reuse_addr() self.bind((host, port)) self.listen(5) diff --git a/Doc/library/atexit.rst b/Doc/library/atexit.rst index cc1051bf74..db99eecbbb 100644 --- a/Doc/library/atexit.rst +++ b/Doc/library/atexit.rst @@ -62,7 +62,8 @@ 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()) + with open("/tmp/counter") as infile: + _count = int(infile.read()) except IOError: _count = 0 @@ -71,7 +72,8 @@ making an explicit call into this module at termination. :: _count = _count + n def savecounter(): - open("/tmp/counter", "w").write("%d" % _count) + with open("/tmp/counter", "w") as outfile: + outfile.write("%d" % _count) import atexit atexit.register(savecounter) diff --git a/Doc/library/bz2.rst b/Doc/library/bz2.rst index d9a2bad756..2ccdb51625 100644 --- a/Doc/library/bz2.rst +++ b/Doc/library/bz2.rst @@ -1,189 +1,149 @@ -:mod:`bz2` --- Compression compatible with :program:`bzip2` -=========================================================== +:mod:`bz2` --- Support for :program:`bzip2` compression +======================================================= .. module:: bz2 - :synopsis: Interface to compression and decompression routines - compatible with bzip2. + :synopsis: Interfaces for bzip2 compression and decompression. .. moduleauthor:: Gustavo Niemeyer <niemeyer@conectiva.com> +.. moduleauthor:: Nadeem Vawda <nadeem.vawda@gmail.com> .. sectionauthor:: Gustavo Niemeyer <niemeyer@conectiva.com> +.. sectionauthor:: Nadeem Vawda <nadeem.vawda@gmail.com> -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. +This module provides a comprehensive interface for compressing and +decompressing data using the bzip2 compression algorithm. -For other archive formats, see the :mod:`gzip`, :mod:`zipfile`, and +For related file formats, see the :mod:`gzip`, :mod:`zipfile`, and :mod:`tarfile` modules. -Here is a summary of the features offered by the bz2 module: +The :mod:`bz2` module contains: -* :class:`BZ2File` class implements a complete file interface, including - :meth:`~BZ2File.readline`, :meth:`~BZ2File.readlines`, - :meth:`~BZ2File.writelines`, :meth:`~BZ2File.seek`, etc; +* The :class:`BZ2File` class for reading and writing compressed files. +* The :class:`BZ2Compressor` and :class:`BZ2Decompressor` classes for + incremental (de)compression. +* The :func:`compress` and :func:`decompress` functions for one-shot + (de)compression. -* :class:`BZ2File` class implements emulated :meth:`~BZ2File.seek` support; - -* :class:`BZ2File` class implements universal newline support; - -* :class:`BZ2File` class offers an optimized line iteration using a readahead - algorithm; - -* 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. +All of the classes in this module may safely be accessed from multiple threads. (De)compression of files ------------------------ -Handling of compressed files is offered by the :class:`BZ2File` class. +.. class:: BZ2File(filename=None, mode='r', buffering=None, compresslevel=9, fileobj=None) + Open a bzip2-compressed file. -.. class:: BZ2File(filename, mode='r', buffering=0, compresslevel=9) + The :class:`BZ2File` can wrap an existing :term:`file object` (given by + *fileobj*), or operate directly on a named file (named by *filename*). + Exactly one of these two parameters should be provided. - 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. - - :class:`BZ2File` supports the :keyword:`with` statement. - - .. versionchanged:: 3.1 - Support for the :keyword:`with` statement was added. + The *mode* argument can be either ``'r'`` for reading (default), or ``'w'`` + for writing. + The *buffering* argument is ignored. Its use is deprecated. - .. method:: close() + If *mode* is ``'w'``, *compresslevel* can be a number between ``1`` and + ``9`` specifying the level of compression: ``1`` produces the least + compression, and ``9`` (default) produces the most compression. - 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. + :class:`BZ2File` provides all of the members specified by the + :class:`io.BufferedIOBase`, except for :meth:`detach` and :meth:`truncate`. + Iteration and the :keyword:`with` statement are supported. + :class:`BZ2File` also provides the following method: - .. method:: read([size]) + .. method:: peek([n]) - Read at most *size* uncompressed bytes, returned as a byte string. If the - *size* argument is negative or omitted, read until EOF is reached. + Return buffered data without advancing the file position. At least one + byte of data will be returned (unless at EOF). The exact number of bytes + returned is unspecified. + .. versionadded:: 3.3 - .. method:: readline([size]) - - Return the next line from the file, as a byte 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 byte - string at EOF. - - - .. method:: 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:: seek(offset[, whence]) + .. versionchanged:: 3.1 + Support for the :keyword:`with` statement was added. - 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). + .. versionchanged:: 3.3 + The :meth:`fileno`, :meth:`readable`, :meth:`seekable`, :meth:`writable`, + :meth:`read1` and :meth:`readinto` methods were added. - Note that seeking of bz2 files is emulated, and depending on the - parameters the operation may be extremely slow. + .. versionchanged:: 3.3 + The *fileobj* argument to the constructor was added. - .. method:: tell() +Incremental (de)compression +--------------------------- - Return the current file position, an integer. +.. class:: BZ2Compressor(compresslevel=9) + Create a new compressor object. This object may be used to compress data + incrementally. For one-shot compression, use the :func:`compress` function + instead. - .. method:: write(data) + *compresslevel*, if given, must be a number between ``1`` and ``9``. The + default is ``9``. - Write the byte string *data* to file. Note that due to buffering, - :meth:`close` may be needed before the file on disk reflects the data - written. + .. method:: compress(data) + Provide data to the compressor object. Returns a chunk of compressed data + if possible, or an empty byte string otherwise. - .. method:: writelines(sequence_of_byte_strings) + When you have finished providing data to the compressor, call the + :meth:`flush` method to finish the compression process. - Write the sequence of byte strings to the file. Note that newlines are not - added. The sequence can be any iterable object producing byte strings. - This is equivalent to calling write() for each byte string. + .. method:: flush() -Sequential (de)compression --------------------------- + Finish the compression process. Returns the compressed data left in + internal buffers. -Sequential compression and decompression is done using the classes -:class:`BZ2Compressor` and :class:`BZ2Decompressor`. + The compressor object may not be used after this method has been called. -.. class:: BZ2Compressor(compresslevel=9) +.. class:: BZ2Decompressor() - 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``. + Create a new decompressor object. This object may be used to decompress data + incrementally. For one-shot compression, use the :func:`decompress` function + instead. - .. method:: compress(data) + .. method:: decompress(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. + Provide data to the decompressor object. Returns a chunk of decompressed + data if possible, or an empty byte string otherwise. + Attempting to decompress data after the end of stream is reached raises + an :exc:`EOFError`. If any data is found after the end of the stream, it + is ignored and saved in the :attr:`unused_data` attribute. - .. method:: flush() - Finish the compression process and return what is left in internal - buffers. You must not use the compressor object after calling this method. + .. attribute:: eof + True if the end-of-stream marker has been reached. -.. class:: BZ2Decompressor() + .. versionadded:: 3.3 - 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:: decompress(data) + .. attribute:: unused_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. + Data found after the end of the compressed stream. One-shot (de)compression ------------------------ -One-shot compression and decompression is provided through the :func:`compress` -and :func:`decompress` functions. +.. function:: compress(data, compresslevel=9) + Compress *data*. -.. function:: compress(data, compresslevel=9) + *compresslevel*, if given, must be a number between ``1`` and ``9``. The + default is ``9``. - 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``. + For incremental compression, use a :class:`BZ2Compressor` instead. .. function:: decompress(data) - Decompress *data* in one shot. If you want to decompress data sequentially, - use an instance of :class:`BZ2Decompressor` instead. + Decompress *data*. + + For incremental decompression, use a :class:`BZ2Decompressor` instead. diff --git a/Doc/library/cmd.rst b/Doc/library/cmd.rst index 464764d793..b33d724618 100644 --- a/Doc/library/cmd.rst +++ b/Doc/library/cmd.rst @@ -282,8 +282,8 @@ immediate playback:: def do_playback(self, arg): 'Playback commands from a file: PLAYBACK rose.cmd' self.close() - cmds = open(arg).read().splitlines() - self.cmdqueue.extend(cmds) + with open(arg) as f: + self.cmdqueue.extend(f.read().splitlines()) def precmd(self, line): line = line.lower() if self.file and 'playback' not in line: diff --git a/Doc/library/codecs.rst b/Doc/library/codecs.rst index 922bcf488a..4d5058ea38 100644 --- a/Doc/library/codecs.rst +++ b/Doc/library/codecs.rst @@ -904,6 +904,15 @@ 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; therefore, e.g. ``'utf-8'`` is a valid alias for the ``'utf_8'`` codec. +.. impl-detail:: + + Some common encodings can bypass the codecs lookup machinery to + improve performance. These optimization opportunities are only + recognized by CPython for a limited set of aliases: utf-8, utf8, + latin-1, latin1, iso-8859-1, mbcs (Windows only), ascii, utf-16, + and utf-32. Using alternative spellings for these encodings may + result in slower execution. + 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 diff --git a/Doc/library/collections.abc.rst b/Doc/library/collections.abc.rst new file mode 100644 index 0000000000..58354f8571 --- /dev/null +++ b/Doc/library/collections.abc.rst @@ -0,0 +1,181 @@ +:mod:`collections.abc` --- Abstract Base Classes for Containers +=============================================================== + +.. module:: collections.abc + :synopsis: Abstract base classes for containers +.. moduleauthor:: Raymond Hettinger <python at rcn.com> +.. sectionauthor:: Raymond Hettinger <python at rcn.com> + +.. testsetup:: * + + from collections import * + import itertools + __name__ = '<doctest>' + +**Source code:** :source:`Lib/collections/abc.py` + +-------------- + +This module provides :term:`abstract base classes <abstract base class>` that +can be used to test whether a class provides a particular interface; for +example, whether it is hashable or whether it is a mapping. + +.. versionchanged:: 3.3 + Formerly, this module was part of the :mod:`collections` module. + +.. _abstract-base-classes: + +Collections Abstract Base Classes +--------------------------------- + +The collections module offers the following :term:`ABCs <abstract base class>`: + +========================= ===================== ====================== ==================================================== +ABC Inherits from Abstract Methods Mixin Methods +========================= ===================== ====================== ==================================================== +:class:`Container` ``__contains__`` +:class:`Hashable` ``__hash__`` +:class:`Iterable` ``__iter__`` +:class:`Iterator` :class:`Iterable` ``__next__`` ``__iter__`` +:class:`Sized` ``__len__`` +:class:`Callable` ``__call__`` + +:class:`Sequence` :class:`Sized`, ``__getitem__`` ``__contains__``, ``__iter__``, ``__reversed__``, + :class:`Iterable`, ``index``, and ``count`` + :class:`Container` + +:class:`MutableSequence` :class:`Sequence` ``__setitem__`` Inherited :class:`Sequence` methods and + ``__delitem__``, ``append``, ``reverse``, ``extend``, ``pop``, + ``insert`` ``remove``, ``clear``, and ``__iadd__`` + +:class:`Set` :class:`Sized`, ``__le__``, ``__lt__``, ``__eq__``, ``__ne__``, + :class:`Iterable`, ``__gt__``, ``__ge__``, ``__and__``, ``__or__``, + :class:`Container` ``__sub__``, ``__xor__``, and ``isdisjoint`` + +:class:`MutableSet` :class:`Set` ``add``, Inherited :class:`Set` methods and + ``discard`` ``clear``, ``pop``, ``remove``, ``__ior__``, + ``__iand__``, ``__ixor__``, and ``__isub__`` + +:class:`Mapping` :class:`Sized`, ``__getitem__`` ``__contains__``, ``keys``, ``items``, ``values``, + :class:`Iterable`, ``get``, ``__eq__``, and ``__ne__`` + :class:`Container` + +:class:`MutableMapping` :class:`Mapping` ``__setitem__``, Inherited :class:`Mapping` methods and + ``__delitem__`` ``pop``, ``popitem``, ``clear``, ``update``, + and ``setdefault`` + + +:class:`MappingView` :class:`Sized` ``__len__`` +:class:`ItemsView` :class:`MappingView`, ``__contains__``, + :class:`Set` ``__iter__`` +:class:`KeysView` :class:`MappingView`, ``__contains__``, + :class:`Set` ``__iter__`` +:class:`ValuesView` :class:`MappingView` ``__contains__``, ``__iter__`` +========================= ===================== ====================== ==================================================== + + +.. class:: Container + Hashable + Sized + Callable + + ABCs for classes that provide respectively the methods :meth:`__contains__`, + :meth:`__hash__`, :meth:`__len__`, and :meth:`__call__`. + +.. class:: Iterable + + ABC for classes that provide the :meth:`__iter__` method. + See also the definition of :term:`iterable`. + +.. class:: Iterator + + ABC for classes that provide the :meth:`__iter__` and :meth:`next` methods. + See also the definition of :term:`iterator`. + +.. class:: Sequence + MutableSequence + + ABCs for read-only and mutable :term:`sequences <sequence>`. + +.. class:: Set + MutableSet + + ABCs for read-only and mutable sets. + +.. class:: Mapping + MutableMapping + + ABCs for read-only and mutable :term:`mappings <mapping>`. + +.. class:: MappingView + ItemsView + KeysView + ValuesView + + ABCs for mapping, items, keys, and values :term:`views <view>`. + + +These ABCs allow us to ask classes or instances if they provide +particular functionality, for example:: + + size = None + if isinstance(myvar, collections.Sized): + size = len(myvar) + +Several of the ABCs are also useful as mixins that make it easier to develop +classes supporting container APIs. For example, to write a class supporting +the full :class:`Set` API, it only necessary to supply the three underlying +abstract methods: :meth:`__contains__`, :meth:`__iter__`, and :meth:`__len__`. +The ABC supplies the remaining methods such as :meth:`__and__` and +:meth:`isdisjoint` :: + + class ListBasedSet(collections.Set): + ''' Alternate set implementation favoring space over speed + and not requiring the set elements to be hashable. ''' + def __init__(self, iterable): + self.elements = lst = [] + for value in iterable: + if value not in lst: + lst.append(value) + def __iter__(self): + return iter(self.elements) + def __contains__(self, value): + return value in self.elements + def __len__(self): + return len(self.elements) + + s1 = ListBasedSet('abcdef') + s2 = ListBasedSet('defghi') + overlap = s1 & s2 # The __and__() method is supported automatically + +Notes on using :class:`Set` and :class:`MutableSet` as a mixin: + +(1) + Since some set operations create new sets, the default mixin methods need + a way to create new instances from an iterable. The class constructor is + assumed to have a signature in the form ``ClassName(iterable)``. + That assumption is factored-out to an internal classmethod called + :meth:`_from_iterable` which calls ``cls(iterable)`` to produce a new set. + If the :class:`Set` mixin is being used in a class with a different + constructor signature, you will need to override :meth:`_from_iterable` + with a classmethod that can construct new instances from + an iterable argument. + +(2) + To override the comparisons (presumably for speed, as the + semantics are fixed), redefine :meth:`__le__` and + then the other operations will automatically follow suit. + +(3) + The :class:`Set` mixin provides a :meth:`_hash` method to compute a hash value + for the set; however, :meth:`__hash__` is not defined because not all sets + are hashable or immutable. To add set hashabilty using mixins, + inherit from both :meth:`Set` and :meth:`Hashable`, then define + ``__hash__ = Set._hash``. + +.. seealso:: + + * `OrderedSet recipe <http://code.activestate.com/recipes/576694/>`_ that uses + :class:`MutableSet`. + + * For more about ABCs, see the :mod:`abc` module and :pep:`3119`. diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst index d29bc175b4..6039a15031 100644 --- a/Doc/library/collections.rst +++ b/Doc/library/collections.rst @@ -13,7 +13,7 @@ import itertools __name__ = '<doctest>' -**Source code:** :source:`Lib/collections.py` and :source:`Lib/_abcoll.py` +**Source code:** :source:`Lib/collections/__init__.py` -------------- @@ -24,6 +24,7 @@ Python's general purpose built-in containers, :class:`dict`, :class:`list`, ===================== ==================================================================== :func:`namedtuple` factory function for creating tuple subclasses with named fields :class:`deque` list-like container with fast appends and pops on either end +:class:`ChainMap` dict-like class for creating a single view of multiple mappings :class:`Counter` dict subclass for counting hashable objects :class:`OrderedDict` dict subclass that remembers the order entries were added :class:`defaultdict` dict subclass that calls a factory function to supply missing values @@ -32,11 +33,125 @@ Python's general purpose built-in containers, :class:`dict`, :class:`list`, :class:`UserString` wrapper around string objects for easier string subclassing ===================== ==================================================================== -In addition to the concrete container classes, the collections module provides -:ref:`abstract-base-classes` that can be used to test whether a class provides a -particular interface, for example, whether it is hashable or a mapping. +.. versionchanged:: 3.3 + Moved :ref:`abstract-base-classes` to the :mod:`collections.abc` module. + For backwards compatibility, they continue to be visible in this module + as well. +:class:`ChainMap` objects +------------------------- + +A :class:`ChainMap` class is provided for quickly linking a number of mappings +so they can be treated as a single unit. It is often much faster than creating +a new dictionary and running multiple :meth:`~dict.update` calls. + +The class can be used to simulate nested scopes and is useful in templating. + +.. class:: ChainMap(*maps) + + A :class:`ChainMap` groups multiple dicts or other mappings together to + create a single, updateable view. If no *maps* are specified, a single empty + dictionary is provided so that a new chain always has at least one mapping. + + The underlying mappings are stored in a list. That list is public and can + accessed or updated using the *maps* attribute. There is no other state. + + Lookups search the underlying mappings successively until a key is found. In + contrast, writes, updates, and deletions only operate on the first mapping. + + A :class:`ChainMap` incorporates the underlying mappings by reference. So, if + one of the underlying mappings gets updated, those changes will be reflected + in :class:`ChainMap`. + + All of the usual dictionary methods are supported. In addition, there is a + *maps* attribute, a method for creating new subcontexts, and a property for + accessing all but the first mapping: + + .. attribute:: maps + + A user updateable list of mappings. The list is ordered from + first-searched to last-searched. It is the only stored state and can + modified to change which mappings are searched. The list should + always contain at least one mapping. + + .. method:: new_child() + + Returns a new :class:`ChainMap` containing a new :class:`dict` followed by + all of the maps in the current instance. A call to ``d.new_child()`` is + equivalent to: ``ChainMap({}, *d.maps)``. This method is used for + creating subcontexts that can be updated without altering values in any + of the parent mappings. + + .. attribute:: parents() + + Returns a new :class:`ChainMap` containing all of the maps in the current + instance except the first one. This is useful for skipping the first map + in the search. The use-cases are similar to those for the + :keyword:`nonlocal` keyword used in :term:`nested scopes <nested scope>`. + The use-cases also parallel those for the builtin :func:`super` function. + A reference to ``d.parents`` is equivalent to: ``ChainMap(*d.maps[1:])``. + + .. versionadded:: 3.3 + + Example of simulating Python's internal lookup chain:: + + import builtins + pylookup = ChainMap(locals(), globals(), vars(builtins)) + + Example of letting user specified values take precedence over environment + variables which in turn take precedence over default values:: + + import os, argparse + defaults = {'color': 'red', 'user': guest} + parser = argparse.ArgumentParser() + parser.add_argument('-u', '--user') + parser.add_argument('-c', '--color') + user_specified = vars(parser.parse_args()) + combined = ChainMap(user_specified, os.environ, defaults) + + Example patterns for using the :class:`ChainMap` class to simulate nested + contexts:: + + c = ChainMap() Create root context + d = c.new_child() Create nested child context + e = c.new_child() Child of c, independent from d + e.maps[0] Current context dictionary -- like Python's locals() + e.maps[-1] Root context -- like Python's globals() + e.parents Enclosing context chain -- like Python's nonlocals + + d['x'] Get first key in the chain of contexts + d['x'] = 1 Set value in current context + del['x'] Delete from current context + list(d) All nested values + k in d Check all nested values + len(d) Number of nested values + d.items() All nested items + dict(d) Flatten into a regular dictionary + + .. seealso:: + + * The `MultiContext class + <http://svn.enthought.com/svn/enthought/CodeTools/trunk/enthought/contexts/multi_context.py>`_ + in the Enthought `CodeTools package + <https://github.com/enthought/codetools>`_ has options to support + writing to any mapping in the chain. + + * Django's `Context class + <http://code.djangoproject.com/browser/django/trunk/django/template/context.py>`_ + for templating is a read-only chain of mappings. It also features + pushing and popping of contexts similar to the + :meth:`~collections.ChainMap.new_child` method and the + :meth:`~collections.ChainMap.parents` property. + + * The `Nested Contexts recipe + <http://code.activestate.com/recipes/577434/>`_ has options to control + whether writes and other mutations apply only to the first mapping or to + any mapping in the chain. + + * A `greatly simplified read-only version of Chainmap + <http://code.activestate.com/recipes/305268/>`_. + :class:`Counter` objects ------------------------ @@ -398,7 +513,8 @@ in Unix:: def tail(filename, n=10): 'Return the last n lines of a file' - return deque(open(filename), n) + with open(filename) as f: + return deque(f, n) Another approach to using deques is to maintain a sequence of recently added elements by appending to the right and popping to the left:: @@ -545,7 +661,7 @@ Setting the :attr:`default_factory` to :class:`set` makes the ... d[k].add(v) ... >>> list(d.items()) - [('blue', set([2, 4])), ('red', set([1, 3]))] + [('blue', {2, 4}), ('red', {1, 3})] :func:`namedtuple` Factory Function for Tuples with Named Fields @@ -578,7 +694,9 @@ they add the ability to access fields by name instead of position index. converted to ``['abc', '_1', 'ghi', '_3']``, eliminating the keyword ``def`` and the duplicate fieldname ``abc``. - If *verbose* is true, the class definition is printed just before being built. + If *verbose* is true, the class definition is printed after it is + built. This option is outdated; instead, it is simpler to print the + :attr:`_source` attribute. Named tuple instances do not have per-instance dictionaries, so they are lightweight and require no more memory than regular tuples. @@ -592,51 +710,6 @@ they add the ability to access fields by name instead of position index. >>> # Basic example >>> Point = namedtuple('Point', ['x', 'y']) - >>> p = Point(x=10, y=11) - - >>> # Example using the verbose option to print the class definition - >>> Point = namedtuple('Point', 'x y', verbose=True) - class Point(tuple): - 'Point(x, y)' - <BLANKLINE> - __slots__ = () - <BLANKLINE> - _fields = ('x', 'y') - <BLANKLINE> - def __new__(_cls, x, y): - 'Create a new instance of Point(x, y)' - return _tuple.__new__(_cls, (x, y)) - <BLANKLINE> - @classmethod - def _make(cls, iterable, new=tuple.__new__, len=len): - 'Make a new Point object from a sequence or iterable' - result = new(cls, iterable) - if len(result) != 2: - raise TypeError('Expected 2 arguments, got %d' % len(result)) - return result - <BLANKLINE> - def __repr__(self): - 'Return a nicely formatted representation string' - return self.__class__.__name__ + '(x=%r, y=%r)' % self - <BLANKLINE> - def _asdict(self): - 'Return a new OrderedDict which maps field names to their values' - return OrderedDict(zip(self._fields, self)) - <BLANKLINE> - def _replace(_self, **kwds): - 'Return a new Point object replacing specified fields with new values' - result = _self._make(map(kwds.pop, ('x', 'y'), _self)) - if kwds: - raise ValueError('Got unexpected field names: %r' % list(kwds.keys())) - return result - <BLANKLINE> - def __getnewargs__(self): - 'Return self as a plain tuple. Used by copy and pickle.' - return tuple(self) - <BLANKLINE> - x = _property(_itemgetter(0), doc='Alias for field number 0') - y = _property(_itemgetter(1), doc='Alias for field number 1') - >>> p = Point(11, y=22) # instantiate with positional or keyword arguments >>> p[0] + p[1] # indexable like the plain tuple (11, 22) 33 @@ -665,7 +738,7 @@ by the :mod:`csv` or :mod:`sqlite3` modules:: print(emp.name, emp.title) In addition to the methods inherited from tuples, named tuples support -three additional methods and one attribute. To prevent conflicts with +three additional methods and two attributes. To prevent conflicts with field names, the method and attribute names start with an underscore. .. classmethod:: somenamedtuple._make(iterable) @@ -703,6 +776,15 @@ field names, the method and attribute names start with an underscore. >>> for partnum, record in inventory.items(): ... inventory[partnum] = record._replace(price=newprices[partnum], timestamp=time.now()) +.. attribute:: somenamedtuple._source + + A string with the pure Python source code used to create the named + tuple class. The source makes the named tuple self-documenting. + It can be printed, executed using :func:`exec`, or saved to a file + and imported. + + .. versionadded:: 3.3 + .. attribute:: somenamedtuple._fields Tuple of strings listing the field names. Useful for introspection @@ -751,7 +833,6 @@ a fixed-width print format: The subclass shown above sets ``__slots__`` to an empty tuple. This helps keep memory requirements low by preventing the creation of instance dictionaries. - Subclassing is not useful for adding new, stored fields. Instead, simply create a new named tuple type from the :attr:`_fields` attribute: @@ -763,6 +844,7 @@ customize a prototype instance: >>> Account = namedtuple('Account', 'owner balance transaction_count') >>> default_account = Account('<owner name>', 0.0, 0) >>> johns_account = default_account._replace(owner='John') + >>> janes_account = default_account._replace(owner='Jane') Enumerated constants can be implemented with named tuples, but it is simpler and more efficient to use a simple class declaration: @@ -985,163 +1067,3 @@ attribute. be an instance of :class:`bytes`, :class:`str`, :class:`UserString` (or a subclass) or an arbitrary sequence which can be converted into a string using the built-in :func:`str` function. - -.. _abstract-base-classes: - -ABCs - abstract base classes ----------------------------- - -The collections module offers the following :term:`ABCs <abstract base class>`: - -========================= ===================== ====================== ==================================================== -ABC Inherits from Abstract Methods Mixin Methods -========================= ===================== ====================== ==================================================== -:class:`Container` ``__contains__`` -:class:`Hashable` ``__hash__`` -:class:`Iterable` ``__iter__`` -:class:`Iterator` :class:`Iterable` ``__next__`` ``__iter__`` -:class:`Sized` ``__len__`` -:class:`Callable` ``__call__`` - -:class:`Sequence` :class:`Sized`, ``__getitem__`` ``__contains__``, ``__iter__``, ``__reversed__``, - :class:`Iterable`, ``index``, and ``count`` - :class:`Container` - -:class:`MutableSequence` :class:`Sequence` ``__setitem__``, Inherited :class:`Sequence` methods and - ``__delitem__``, ``append``, ``reverse``, ``extend``, ``pop``, - ``insert`` ``remove``, and ``__iadd__`` - -:class:`Set` :class:`Sized`, ``__le__``, ``__lt__``, ``__eq__``, ``__ne__``, - :class:`Iterable`, ``__gt__``, ``__ge__``, ``__and__``, ``__or__``, - :class:`Container` ``__sub__``, ``__xor__``, and ``isdisjoint`` - -:class:`MutableSet` :class:`Set` ``add``, Inherited :class:`Set` methods and - ``discard`` ``clear``, ``pop``, ``remove``, ``__ior__``, - ``__iand__``, ``__ixor__``, and ``__isub__`` - -:class:`Mapping` :class:`Sized`, ``__getitem__`` ``__contains__``, ``keys``, ``items``, ``values``, - :class:`Iterable`, ``get``, ``__eq__``, and ``__ne__`` - :class:`Container` - -:class:`MutableMapping` :class:`Mapping` ``__setitem__``, Inherited :class:`Mapping` methods and - ``__delitem__`` ``pop``, ``popitem``, ``clear``, ``update``, - and ``setdefault`` - - -:class:`MappingView` :class:`Sized` ``__len__`` -:class:`ItemsView` :class:`MappingView`, ``__contains__``, - :class:`Set` ``__iter__`` -:class:`KeysView` :class:`MappingView`, ``__contains__``, - :class:`Set` ``__iter__`` -:class:`ValuesView` :class:`MappingView` ``__contains__``, ``__iter__`` -========================= ===================== ====================== ==================================================== - - -.. class:: Container - Hashable - Sized - Callable - - ABCs for classes that provide respectively the methods :meth:`__contains__`, - :meth:`__hash__`, :meth:`__len__`, and :meth:`__call__`. - -.. class:: Iterable - - ABC for classes that provide the :meth:`__iter__` method. - See also the definition of :term:`iterable`. - -.. class:: Iterator - - ABC for classes that provide the :meth:`__iter__` and :meth:`next` methods. - See also the definition of :term:`iterator`. - -.. class:: Sequence - MutableSequence - - ABCs for read-only and mutable :term:`sequences <sequence>`. - -.. class:: Set - MutableSet - - ABCs for read-only and mutable sets. - -.. class:: Mapping - MutableMapping - - ABCs for read-only and mutable :term:`mappings <mapping>`. - -.. class:: MappingView - ItemsView - KeysView - ValuesView - - ABCs for mapping, items, keys, and values :term:`views <view>`. - - -These ABCs allow us to ask classes or instances if they provide -particular functionality, for example:: - - size = None - if isinstance(myvar, collections.Sized): - size = len(myvar) - -Several of the ABCs are also useful as mixins that make it easier to develop -classes supporting container APIs. For example, to write a class supporting -the full :class:`Set` API, it only necessary to supply the three underlying -abstract methods: :meth:`__contains__`, :meth:`__iter__`, and :meth:`__len__`. -The ABC supplies the remaining methods such as :meth:`__and__` and -:meth:`isdisjoint` :: - - class ListBasedSet(collections.Set): - ''' Alternate set implementation favoring space over speed - and not requiring the set elements to be hashable. ''' - def __init__(self, iterable): - self.elements = lst = [] - for value in iterable: - if value not in lst: - lst.append(value) - def __iter__(self): - return iter(self.elements) - def __contains__(self, value): - return value in self.elements - def __len__(self): - return len(self.elements) - - s1 = ListBasedSet('abcdef') - s2 = ListBasedSet('defghi') - overlap = s1 & s2 # The __and__() method is supported automatically - -Notes on using :class:`Set` and :class:`MutableSet` as a mixin: - -(1) - Since some set operations create new sets, the default mixin methods need - a way to create new instances from an iterable. The class constructor is - assumed to have a signature in the form ``ClassName(iterable)``. - That assumption is factored-out to an internal classmethod called - :meth:`_from_iterable` which calls ``cls(iterable)`` to produce a new set. - If the :class:`Set` mixin is being used in a class with a different - constructor signature, you will need to override :meth:`_from_iterable` - with a classmethod that can construct new instances from - an iterable argument. - -(2) - To override the comparisons (presumably for speed, as the - semantics are fixed), redefine :meth:`__le__` and - then the other operations will automatically follow suit. - -(3) - The :class:`Set` mixin provides a :meth:`_hash` method to compute a hash value - for the set; however, :meth:`__hash__` is not defined because not all sets - are hashable or immutable. To add set hashabilty using mixins, - inherit from both :meth:`Set` and :meth:`Hashable`, then define - ``__hash__ = Set._hash``. - -.. seealso:: - - * Latest version of the :source:`Python source code for the collections - abstract base classes <Lib/_abcoll.py>` - - * `OrderedSet recipe <http://code.activestate.com/recipes/576694/>`_ for an - example built on :class:`MutableSet`. - - * For more about ABCs, see the :mod:`abc` module and :pep:`3119`. diff --git a/Doc/library/crypt.rst b/Doc/library/crypt.rst index 0be571eb51..ec5a4b0ae2 100644 --- a/Doc/library/crypt.rst +++ b/Doc/library/crypt.rst @@ -15,9 +15,9 @@ 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. +page for further details. Possible uses include storing hashed passwords +so you can check passwords without storing the actual password, or attempting +to crack Unix passwords with a dictionary. .. index:: single: crypt(3) @@ -26,15 +26,81 @@ the :manpage:`crypt(3)` routine in the running system. Therefore, any extensions available on the current implementation will also be available on this module. +Hashing Methods +--------------- -.. function:: crypt(word, salt) +The :mod:`crypt` module defines the list of hashing methods (not all methods +are available on all platforms): + +.. data:: METHOD_SHA512 + + A Modular Crypt Format method with 16 character salt and 86 character + hash. This is the strongest method. + + .. versionadded:: 3.3 + +.. data:: METHOD_SHA256 + + Another Modular Crypt Format method with 16 character salt and 43 + character hash. + + .. versionadded:: 3.3 + +.. data:: METHOD_MD5 + + Another Modular Crypt Format method with 8 character salt and 22 + character hash. + + .. versionadded:: 3.3 + +.. data:: METHOD_CRYPT + + The traditional method with a 2 character salt and 13 characters of + hash. This is the weakest method. + + .. versionadded:: 3.3 + + +Module Attributes +----------------- + + +.. attribute:: methods + + A list of available password hashing algorithms, as + ``crypt.METHOD_*`` objects. This list is sorted from strongest to + weakest, and is guaranteed to have at least ``crypt.METHOD_CRYPT``. + + .. versionadded:: 3.3 + + +Module Functions +---------------- + +The :mod:`crypt` module defines the following functions: + +.. function:: crypt(word, salt=None) *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). + interface. The optional *salt* is either a string as returned from + :func:`mksalt`, one of the ``crypt.METHOD_*`` values (though not all + may be available on all platforms), or a full encrypted password + including salt, as returned by this function. If *salt* is not + provided, the strongest method will be used (as returned by + :func:`methods`. + + Checking a password is usually done by passing the plain-text password + as *word* and the full results of a previous :func:`crypt` call, + which should be the same as the results of this call. + + *salt* (either a random 2 or 16 character string, possibly prefixed with + ``$digit$`` to indicate the method) which will be used to perturb the + encryption algorithm. The characters in *salt* must be in the set + ``[./a-zA-Z0-9]``, with the exception of Modular Crypt Format which + prefixes a ``$digit$``. + + Returns the hashed password as a string, which will be composed of + characters from the same alphabet as the salt. .. index:: single: crypt(3) @@ -42,6 +108,27 @@ this module. different sizes in the *salt*, it is recommended to use the full crypted password as salt when checking for a password. +.. versionchanged:: 3.3 + Before version 3.3, *salt* must be specified as a string and cannot + accept ``crypt.METHOD_*`` values (which don't exist anyway). + + +.. function:: mksalt(method=None) + + Return a randomly generated salt of the specified method. If no + *method* is given, the strongest method available as returned by + :func:`methods` is used. + + The return value is a string either of 2 characters in length for + ``crypt.METHOD_CRYPT``, or 19 characters starting with ``$digit$`` and + 16 random characters from the set ``[./a-zA-Z0-9]``, suitable for + passing as the *salt* argument to :func:`crypt`. + +.. versionadded:: 3.3 + +Examples +-------- + A simple example illustrating typical use:: import crypt, getpass, pwd @@ -57,3 +144,11 @@ A simple example illustrating typical use:: else: return 1 +To generate a hash of a password using the strongest available method and +check it against the original:: + + import crypt + + hashed = crypt.crypt(plaintext) + if hashed != crypt.crypt(plaintext, hashed): + raise "Hashed version doesn't validate against original" diff --git a/Doc/library/csv.rst b/Doc/library/csv.rst index edbe7263df..ec0dfccfab 100644 --- a/Doc/library/csv.rst +++ b/Doc/library/csv.rst @@ -11,15 +11,15 @@ 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. +export format for spreadsheets and databases. CSV format was used for many +years prior to attempts to describe the format in a standardized way in +:rfc:`4180`. The lack of a well-defined 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 diff --git a/Doc/library/datatypes.rst b/Doc/library/datatypes.rst index 6b4a71a3ad..8e33c1ff4e 100644 --- a/Doc/library/datatypes.rst +++ b/Doc/library/datatypes.rst @@ -21,6 +21,7 @@ The following modules are documented in this chapter: datetime.rst calendar.rst collections.rst + collections.abc.rst heapq.rst bisect.rst array.rst diff --git a/Doc/library/datetime.rst b/Doc/library/datetime.rst index de9ad449b2..c637f6a44d 100644 --- a/Doc/library/datetime.rst +++ b/Doc/library/datetime.rst @@ -721,6 +721,22 @@ Other constructors, all class methods: It's common for this to be restricted to years in 1970 through 2038. See also :meth:`fromtimestamp`. + On the POSIX compliant platforms, ``utcfromtimestamp(timestamp)`` + is equivalent to the following expression:: + + datetime(1970, 1, 1) + timedelta(seconds=timestamp) + + There is no method to obtain the timestamp from a :class:`datetime` + instance, but POSIX timestamp corresponding to a :class:`datetime` + instance ``dt`` can be easily calculated as follows. For a naive + ``dt``:: + + timestamp = (dt - datetime(1970, 1, 1)) / timedelta(seconds=1) + + And for an aware ``dt``:: + + timestamp = (dt - datetime(1970, 1, 1, tzinfo=timezone.utc)) / timedelta(seconds=1) + .. classmethod:: datetime.fromordinal(ordinal) diff --git a/Doc/library/debug.rst b/Doc/library/debug.rst index b2ee4fa098..c69fb1c846 100644 --- a/Doc/library/debug.rst +++ b/Doc/library/debug.rst @@ -10,7 +10,8 @@ allowing you to identify bottlenecks in your programs. .. toctree:: bdb.rst + faulthandler.rst pdb.rst profile.rst timeit.rst - trace.rst
\ No newline at end of file + trace.rst diff --git a/Doc/library/difflib.rst b/Doc/library/difflib.rst index bdc37b3e0a..836e240b83 100644 --- a/Doc/library/difflib.rst +++ b/Doc/library/difflib.rst @@ -752,8 +752,8 @@ It is also contained in the Python source distribution, as # we're passing these as arguments to the diff function fromdate = time.ctime(os.stat(fromfile).st_mtime) todate = time.ctime(os.stat(tofile).st_mtime) - fromlines = open(fromfile, 'U').readlines() - tolines = open(tofile, 'U').readlines() + with open(fromlines) as fromf, open(tofile) as tof: + fromlines, tolines = list(fromf), list(tof) if options.u: diff = difflib.unified_diff(fromlines, tolines, fromfile, tofile, diff --git a/Doc/library/email.generator.rst b/Doc/library/email.generator.rst index 85b32fe7fe..847d7e4a0f 100644 --- a/Doc/library/email.generator.rst +++ b/Doc/library/email.generator.rst @@ -32,7 +32,8 @@ Here are the public methods of the :class:`Generator` class, imported from the :mod:`email.generator` module: -.. class:: Generator(outfp, mangle_from_=True, maxheaderlen=78) +.. class:: Generator(outfp, mangle_from_=True, maxheaderlen=78, *, \ + policy=policy.default) The constructor for the :class:`Generator` class takes a :term:`file-like object` called *outfp* for an argument. *outfp* must support the :meth:`write` method @@ -53,10 +54,16 @@ Here are the public methods of the :class:`Generator` class, imported from the :class:`~email.header.Header` class. Set to zero to disable header wrapping. The default is 78, as recommended (but not required) by :rfc:`2822`. + The *policy* keyword specifies a :mod:`~email.policy` object that controls a + number of aspects of the generator's operation. The default policy + maintains backward compatibility. + + .. versionchanged:: 3.3 Added the *policy* keyword. + The other public :class:`Generator` methods are: - .. method:: flatten(msg, unixfrom=False, linesep='\\n') + .. method:: flatten(msg, unixfrom=False, linesep=None) Print the textual representation of the message object structure rooted at *msg* to the output file specified when the :class:`Generator` instance @@ -72,12 +79,13 @@ Here are the public methods of the :class:`Generator` class, imported from the Note that for subparts, no envelope header is ever printed. Optional *linesep* specifies the line separator character used to - terminate lines in the output. It defaults to ``\n`` because that is - the most useful value for Python application code (other library packages - expect ``\n`` separated lines). ``linesep=\r\n`` can be used to - generate output with RFC-compliant line separators. + terminate lines in the output. If specified it overrides the value + specified by the ``Generator``\'s ``policy``. - Messages parsed with a Bytes parser that have a + Because strings cannot represent non-ASCII bytes, ``Generator`` ignores + the value of the :attr:`~email.policy.Policy.must_be_7bit` + :mod:`~email.policy` setting and operates as if it were set ``True``. + This means that messages parsed with a Bytes parser that have a :mailheader:`Content-Transfer-Encoding` of 8bit will be converted to a use a 7bit Content-Transfer-Encoding. Non-ASCII bytes in the headers will be :rfc:`2047` encoded with a charset of `unknown-8bit`. @@ -103,7 +111,8 @@ As a convenience, see the :class:`~email.message.Message` methods formatted string representation of a message object. For more detail, see :mod:`email.message`. -.. class:: BytesGenerator(outfp, mangle_from_=True, maxheaderlen=78) +.. class:: BytesGenerator(outfp, mangle_from_=True, maxheaderlen=78, *, \ + policy=policy.default) The constructor for the :class:`BytesGenerator` class takes a binary :term:`file-like object` called *outfp* for an argument. *outfp* must @@ -125,19 +134,31 @@ formatted string representation of a message object. For more detail, see wrapping. The default is 78, as recommended (but not required) by :rfc:`2822`. + The *policy* keyword specifies a :mod:`~email.policy` object that controls a + number of aspects of the generator's operation. The default policy + maintains backward compatibility. + + .. versionchanged:: 3.3 Added the *policy* keyword. + The other public :class:`BytesGenerator` methods are: - .. method:: flatten(msg, unixfrom=False, linesep='\n') + .. method:: flatten(msg, unixfrom=False, linesep=None) Print the textual representation of the message object structure rooted at *msg* to the output file specified when the :class:`BytesGenerator` instance was created. Subparts are visited depth-first and the resulting - text will be properly MIME encoded. If the input that created the *msg* - contained bytes with the high bit set and those bytes have not been - modified, they will be copied faithfully to the output, even if doing so - is not strictly RFC compliant. (To produce strictly RFC compliant - output, use the :class:`Generator` class.) + text will be properly MIME encoded. If the :mod:`~email.policy` option + :attr:`~email.policy.Policy.must_be_7bit` is ``False`` (the default), + then any bytes with the high bit set in the original parsed message that + have not been modified will be copied faithfully to the output. If + ``must_be_7bit`` is true, the bytes will be converted as needed using an + ASCII content-transfer-encoding. In particular, RFC-invalid non-ASCII + bytes in headers will be encoded using the MIME ``unknown-8bit`` + character set, thus rendering them RFC-compliant. + + .. XXX: There should be a complementary option that just does the RFC + compliance transformation but leaves CTE 8bit parts alone. Messages parsed with a Bytes parser that have a :mailheader:`Content-Transfer-Encoding` of 8bit will be reconstructed @@ -152,10 +173,8 @@ formatted string representation of a message object. For more detail, see Note that for subparts, no envelope header is ever printed. Optional *linesep* specifies the line separator character used to - terminate lines in the output. It defaults to ``\n`` because that is - the most useful value for Python application code (other library packages - expect ``\n`` separated lines). ``linesep=\r\n`` can be used to - generate output with RFC-compliant line separators. + terminate lines in the output. If specified it overrides the value + specified by the ``Generator``\ 's ``policy``. .. method:: clone(fp) diff --git a/Doc/library/email.parser.rst b/Doc/library/email.parser.rst index 77a0b698d1..e70b429b42 100644 --- a/Doc/library/email.parser.rst +++ b/Doc/library/email.parser.rst @@ -58,12 +58,18 @@ list of defects that it can find. Here is the API for the :class:`FeedParser`: -.. class:: FeedParser(_factory=email.message.Message) +.. class:: FeedParser(_factory=email.message.Message, *, policy=policy.default) 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. + The *policy* keyword specifies a :mod:`~email.policy` object that controls a + number of aspects of the parser's operation. The default policy maintains + backward compatibility. + + .. versionchanged:: 3.3 Added the *policy* keyword. + .. method:: feed(data) Feed the :class:`FeedParser` some more data. *data* should be a string @@ -94,15 +100,17 @@ 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. +module also provides header-only parsers, called :class:`HeaderParser` and +:class:`BytesHeaderParser`, which can be used if you're only interested in the +headers of the message. :class:`HeaderParser` and :class:`BytesHeaderParser` +can be much faster in these situations, since they do not attempt to parse the +message body, instead setting the payload to the raw body as a string. They +have the same API as the :class:`Parser` and :class:`BytesParser` classes. +.. versionadded:: 3.3 BytesHeaderParser -.. class:: Parser(_class=email.message.Message, strict=None) + +.. class:: Parser(_class=email.message.Message, *, policy=policy.default) 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 @@ -110,13 +118,13 @@ class. :class:`~email.message.Message` (see :mod:`email.message`). The factory will be called without arguments. - The optional *strict* flag is ignored. + The *policy* keyword specifies a :mod:`~email.policy` object that controls a + number of aspects of the parser's operation. The default policy maintains + backward compatibility. - .. 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:: 3.3 + Removed the *strict* argument that was deprecated in 2.4. Added the + *policy* keyword. The other public :class:`Parser` methods are: @@ -147,12 +155,18 @@ class. the entire contents of the file. -.. class:: BytesParser(_class=email.message.Message, strict=None) +.. class:: BytesParser(_class=email.message.Message, *, policy=policy.default) This class is exactly parallel to :class:`Parser`, but handles bytes input. The *_class* and *strict* arguments are interpreted in the same way as for - the :class:`Parser` constructor. *strict* is supported only to make porting - code easier; it is deprecated. + the :class:`Parser` constructor. + + The *policy* keyword specifies a :mod:`~email.policy` object that + controls a number of aspects of the parser's operation. The default + policy maintains backward compatibility. + + .. versionchanged:: 3.3 + Removed the *strict* argument. Added the *policy* keyword. .. method:: parse(fp, headeronly=False) @@ -190,34 +204,48 @@ in the top-level :mod:`email` package namespace. .. currentmodule:: email -.. function:: message_from_string(s, _class=email.message.Message, strict=None) +.. function:: message_from_string(s, _class=email.message.Message, *, \ + policy=policy.default) Return a message object structure from a string. This is exactly equivalent to - ``Parser().parsestr(s)``. Optional *_class* and *strict* are interpreted as + ``Parser().parsestr(s)``. *_class* and *policy* are interpreted as with the :class:`Parser` class constructor. -.. function:: message_from_bytes(s, _class=email.message.Message, strict=None) + .. versionchanged:: 3.3 + Removed the *strict* argument. Added the *policy* keyword. + +.. function:: message_from_bytes(s, _class=email.message.Message, *, \ + policy=policy.default) Return a message object structure from a byte string. This is exactly equivalent to ``BytesParser().parsebytes(s)``. Optional *_class* and *strict* are interpreted as with the :class:`Parser` class constructor. .. versionadded:: 3.2 + .. versionchanged:: 3.3 + Removed the *strict* argument. Added the *policy* keyword. -.. function:: message_from_file(fp, _class=email.message.Message, strict=None) +.. function:: message_from_file(fp, _class=email.message.Message, *, \ + policy=policy.default) Return a message object structure tree from an open :term:`file object`. - This is exactly equivalent to ``Parser().parse(fp)``. Optional *_class* - and *strict* are interpreted as with the :class:`Parser` class constructor. + This is exactly equivalent to ``Parser().parse(fp)``. *_class* + and *policy* are interpreted as with the :class:`Parser` class constructor. + + .. versionchanged:: + Removed the *strict* argument. Added the *policy* keyword. -.. function:: message_from_binary_file(fp, _class=email.message.Message, strict=None) +.. function:: message_from_binary_file(fp, _class=email.message.Message, *, \ + policy=policy.default) Return a message object structure tree from an open binary :term:`file object`. This is exactly equivalent to ``BytesParser().parse(fp)``. - Optional *_class* and *strict* are interpreted as with the :class:`Parser` + *_class* and *policy* are interpreted as with the :class:`Parser` class constructor. .. versionadded:: 3.2 + .. versionchanged:: 3.3 + Removed the *strict* argument. Added the *policy* keyword. Here's an example of how you might use this at an interactive Python prompt:: diff --git a/Doc/library/email.policy.rst b/Doc/library/email.policy.rst new file mode 100644 index 0000000000..157f692267 --- /dev/null +++ b/Doc/library/email.policy.rst @@ -0,0 +1,182 @@ +:mod:`email`: Policy Objects +---------------------------- + +.. module:: email.policy + :synopsis: Controlling the parsing and generating of messages + +.. versionadded: 3.3 + + +The :mod:`email` package's prime focus is the handling of email messages as +described by the various email and MIME RFCs. However, the general format of +email messages (a block of header fields each consisting of a name followed by +a colon followed by a value, the whole block followed by a blank line and an +arbitrary 'body'), is a format that has found utility outside of the realm of +email. Some of these uses conform fairly closely to the main RFCs, some do +not. And even when working with email, there are times when it is desirable to +break strict compliance with the RFCs. + +Policy objects give the email package the flexibility to handle all these +disparate use cases. + +A :class:`Policy` object encapsulates a set of attributes and methods that +control the behavior of various components of the email package during use. +:class:`Policy` instances can be passed to various classes and methods in the +email package to alter the default behavior. The settable values and their +defaults are described below. The :mod:`policy` module also provides some +pre-created :class:`Policy` instances. In addition to a :const:`default` +instance, there are instances tailored for certain applications. For example +there is an :const:`SMTP` :class:`Policy` with defaults appropriate for +generating output to be sent to an SMTP server. These are listed `below +<Policy Instances>`. + +In general an application will only need to deal with setting the policy at the +input and output boundaries. Once parsed, a message is represented by a +:class:`~email.message.Message` object, which is designed to be independent of +the format that the message has "on the wire" when it is received, transmitted, +or displayed. Thus, a :class:`Policy` can be specified when parsing a message +to create a :class:`~email.message.Message`, and again when turning the +:class:`~email.message.Message` into some other representation. While often a +program will use the same :class:`Policy` for both input and output, the two +can be different. + +As an example, the following code could be used to read an email message from a +file on disk and pass it to the system ``sendmail`` program on a Unix system:: + + >>> from email import msg_from_binary_file + >>> from email.generator import BytesGenerator + >>> import email.policy + >>> from subprocess import Popen, PIPE + >>> with open('mymsg.txt', 'b') as f: + ... Msg = msg_from_binary_file(f, policy=email.policy.mbox) + >>> p = Popen(['sendmail', msg['To'][0].address], stdin=PIPE) + >>> g = BytesGenerator(p.stdin, policy=email.policy.SMTP) + >>> g.flatten(msg) + >>> p.stdin.close() + >>> rc = p.wait() + +Some email package methods accept a *policy* keyword argument, allowing the +policy to be overridden for that method. For example, the following code uses +the :meth:`email.message.Message.as_string` method of the *msg* object from the +previous example and re-write it to a file using the native line separators for +the platform on which it is running:: + + >>> import os + >>> mypolicy = email.policy.Policy(linesep=os.linesep) + >>> with open('converted.txt', 'wb') as f: + ... f.write(msg.as_string(policy=mypolicy)) + +Policy instances are immutable, but they can be cloned, accepting the same +keyword arguments as the class constructor and returning a new :class:`Policy` +instance that is a copy of the original but with the specified attributes +values changed. For example, the following creates an SMTP policy that will +raise any defects detected as errors:: + + >>> strict_SMTP = email.policy.SMTP.clone(raise_on_defect=True) + +Policy objects can also be combined using the addition operator, producing a +policy object whose settings are a combination of the non-default values of the +summed objects:: + + >>> strict_SMTP = email.policy.SMTP + email.policy.strict + +This operation is not commutative; that is, the order in which the objects are +added matters. To illustrate:: + + >>> Policy = email.policy.Policy + >>> apolicy = Policy(max_line_length=100) + Policy(max_line_length=80) + >>> apolicy.max_line_length + 80 + >>> apolicy = Policy(max_line_length=80) + Policy(max_line_length=100) + >>> apolicy.max_line_length + 100 + + +.. class:: Policy(**kw) + + The valid constructor keyword arguments are any of the attributes listed + below. + + .. attribute:: max_line_length + + The maximum length of any line in the serialized output, not counting the + end of line character(s). Default is 78, per :rfc:`5322`. A value of + ``0`` or :const:`None` indicates that no line wrapping should be + done at all. + + .. attribute:: linesep + + The string to be used to terminate lines in serialized output. The + default is ``\n`` because that's the internal end-of-line discipline used + by Python, though ``\r\n`` is required by the RFCs. See `Policy + Instances`_ for policies that use an RFC conformant linesep. Setting it + to :attr:`os.linesep` may also be useful. + + .. attribute:: must_be_7bit + + If ``True``, data output by a bytes generator is limited to ASCII + characters. If :const:`False` (the default), then bytes with the high + bit set are preserved and/or allowed in certain contexts (for example, + where possible a content transfer encoding of ``8bit`` will be used). + String generators act as if ``must_be_7bit`` is ``True`` regardless of + the policy in effect, since a string cannot represent non-ASCII bytes. + + .. attribute:: raise_on_defect + + If :const:`True`, any defects encountered will be raised as errors. If + :const:`False` (the default), defects will be passed to the + :meth:`register_defect` method. + + :mod:`Policy` object also have the following methods: + + .. method:: handle_defect(obj, defect) + + *obj* is the object on which to register the defect. *defect* should be + an instance of a subclass of :class:`~email.errors.Defect`. + If :attr:`raise_on_defect` + is ``True`` the defect is raised as an exception. Otherwise *obj* and + *defect* are passed to :meth:`register_defect`. This method is intended + to be called by parsers when they encounter defects, and will not be + called by code that uses the email library unless that code is + implementing an alternate parser. + + .. method:: register_defect(obj, defect) + + *obj* is the object on which to register the defect. *defect* should be + a subclass of :class:`~email.errors.Defect`. This method is part of the + public API so that custom ``Policy`` subclasses can implement alternate + handling of defects. The default implementation calls the ``append`` + method of the ``defects`` attribute of *obj*. + + .. method:: clone(obj, *kw) + + Return a new :class:`Policy` instance whose attributes have the same + values as the current instance, except where those attributes are + given new values by the keyword arguments. + + +Policy Instances +^^^^^^^^^^^^^^^^ + +The following instances of :class:`Policy` provide defaults suitable for +specific common application domains. + +.. data:: default + + An instance of :class:`Policy` with all defaults unchanged. + +.. data:: SMTP + + Output serialized from a message will conform to the email and SMTP + RFCs. The only changed attribute is :attr:`linesep`, which is set to + ``\r\n``. + +.. data:: HTTP + + Suitable for use when serializing headers for use in HTTP traffic. + :attr:`linesep` is set to ``\r\n``, and :attr:`max_line_length` is set to + :const:`None` (unlimited). + +.. data:: strict + + :attr:`raise_on_defect` is set to :const:`True`. diff --git a/Doc/library/email.rst b/Doc/library/email.rst index 4530b9506e..fc206f4db2 100644 --- a/Doc/library/email.rst +++ b/Doc/library/email.rst @@ -51,6 +51,7 @@ Contents of the :mod:`email` package documentation: email.message.rst email.parser.rst email.generator.rst + email.policy.rst email.mime.rst email.header.rst email.charset.rst diff --git a/Doc/library/email.util.rst b/Doc/library/email.util.rst index f7b777a01d..4d96857c83 100644 --- a/Doc/library/email.util.rst +++ b/Doc/library/email.util.rst @@ -29,13 +29,20 @@ There are several useful utilities provided in the :mod:`email.utils` module: fails, in which case a 2-tuple of ``('', '')`` is returned. -.. function:: formataddr(pair) +.. function:: formataddr(pair, charset='utf-8') 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. + Optional *charset* is the character set that will be used in the :rfc:`2047` + encoding of the ``realname`` if the ``realname`` contains non-ASCII + characters. Can be an instance of :class:`str` or a + :class:`~email.charset.Charset`. Defaults to ``utf-8``. + + .. versionchanged: 3.3 added the *charset* option + .. function:: getaddresses(fieldvalues) diff --git a/Doc/library/faulthandler.rst b/Doc/library/faulthandler.rst new file mode 100644 index 0000000000..c0b662502f --- /dev/null +++ b/Doc/library/faulthandler.rst @@ -0,0 +1,130 @@ +:mod:`faulthandler` --- Dump the Python traceback +================================================= + +.. module:: faulthandler + :synopsis: Dump the Python traceback. + +This module contains functions to dump the Python traceback explicitly, on a +fault, after a timeout or on a user signal. Call :func:`faulthandler.enable` to +install fault handlers for :const:`SIGSEGV`, :const:`SIGFPE`, :const:`SIGABRT`, +:const:`SIGBUS` and :const:`SIGILL` signals. You can also enable them at +startup by setting the :envvar:`PYTHONFAULTHANDLER` environment variable or by +using :option:`-X` ``faulthandler`` command line option. + +The fault handler is compatible with system fault handlers like Apport or +the Windows fault handler. The module uses an alternative stack for signal +handlers, if the :c:func:`sigaltstack` function is available, to be able to +dump the traceback even on a stack overflow. + +The fault handler is called on catastrophic cases and so can only use +signal-safe functions (e.g. it cannot allocate memory on the heap). That's why +the traceback is limited: only support ASCII encoding (use the +``backslashreplace`` error handler), limit each string to 100 characters, don't +print the source code (only the filename, the function name and the line +number), limit to 100 frames and 100 threads. + +By default, the Python traceback is written to :data:`sys.stderr`. Start your +graphical applications in a terminal and run your server in foreground to see +the traceback, or specify a log file to :func:`faulthandler.enable()`. + +The module is implemented in C to be able to dump a traceback on a crash or +when Python is blocked (e.g. deadlock). + +.. versionadded:: 3.3 + + +Dump the traceback +------------------ + +.. function:: dump_traceback(file=sys.stderr, all_threads=False) + + Dump the traceback of the current thread, or of all threads if *all_threads* + is ``True``, into *file*. + + +Fault handler state +------------------- + +.. function:: enable(file=sys.stderr, all_threads=False) + + Enable the fault handler: install handlers for :const:`SIGSEGV`, + :const:`SIGFPE`, :const:`SIGABRT`, :const:`SIGBUS` and :const:`SIGILL` + signals to dump the Python traceback. It dumps the traceback of the current + thread, or all threads if *all_threads* is ``True``, into *file*. + +.. function:: disable() + + Disable the fault handler: uninstall the signal handlers installed by + :func:`enable`. + +.. function:: is_enabled() + + Check if the fault handler is enabled. + + +Dump the tracebacks after a timeout +----------------------------------- + +.. function:: dump_tracebacks_later(timeout, repeat=False, file=sys.stderr, exit=False) + + Dump the tracebacks of all threads, after a timeout of *timeout* seconds, or + each *timeout* seconds if *repeat* is ``True``. If *exit* is True, call + :c:func:`_exit` with status=1 after dumping the tracebacks to terminate + immediatly the process, which is not safe. For example, :c:func:`_exit` + doesn't flush file buffers. If the function is called twice, the new call + replaces previous parameters (resets the timeout). The timer has a + sub-second resolution. + + This function is implemented using a watchdog thread, and therefore is + not available if Python is compiled with threads disabled. + +.. function:: cancel_dump_tracebacks_later() + + Cancel the last call to :func:`dump_tracebacks_later`. + + +Dump the traceback on a user signal +----------------------------------- + +.. function:: register(signum, file=sys.stderr, all_threads=False) + + Register a user signal: install a handler for the *signum* signal to dump + the traceback of the current thread, or of all threads if *all_threads* is + ``True``, into *file*. + + Not available on Windows. + +.. function:: unregister(signum) + + Unregister a user signal: uninstall the handler of the *signum* signal + installed by :func:`register`. Return ``True`` if the signal was registered, + ``False`` otherwise. + + Not available on Windows. + + +File descriptor issue +--------------------- + +:func:`enable`, :func:`dump_tracebacks_later` and :func:`register` keep the +file descriptor of their *file* argument. If the file is closed and its file +descriptor is reused by a new file, or if :func:`os.dup2` is used to replace +the file descriptor, the traceback will be written into a different file. Call +these functions again each time that the file is replaced. + + +Example +------- + +Example of a segmentation fault on Linux: :: + + $ python -q -X faulthandler + >>> import ctypes + >>> ctypes.string_at(0) + Fatal Python error: Segmentation fault + + Traceback (most recent call first): + File "/home/python/cpython/Lib/ctypes/__init__.py", line 486 in string_at + File "<stdin>", line 1 in <module> + Segmentation fault + diff --git a/Doc/library/ftplib.rst b/Doc/library/ftplib.rst index 5bbef4f233..8283a452d6 100644 --- a/Doc/library/ftplib.rst +++ b/Doc/library/ftplib.rst @@ -40,7 +40,7 @@ Here's a sample session using the :mod:`ftplib` module:: The module defines the following items: -.. class:: FTP(host='', user='', passwd='', acct=''[, timeout]) +.. class:: FTP(host='', user='', passwd='', acct='', timeout=None, source_address=None) 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 @@ -48,7 +48,8 @@ The module defines the following items: *acct* default to the empty string when not given). The optional *timeout* parameter specifies a timeout in seconds for blocking operations like the connection attempt (if is not specified, the global default timeout setting - will be used). + will be used). *source_address* is a 2-tuple ``(host, port)`` for the socket + to bind to as its source address before connecting. :class:`FTP` class supports the :keyword:`with` statement. Here is a sample on how using it: @@ -68,8 +69,11 @@ The module defines the following items: .. versionchanged:: 3.2 Support for the :keyword:`with` statement was added. + .. versionchanged:: 3.3 + *source_address* parameter was added. -.. class:: FTP_TLS(host='', user='', passwd='', acct='', [keyfile[, certfile[, context[, timeout]]]]) + +.. class:: FTP_TLS(host='', user='', passwd='', acct='', keyfile=None, certfile=None, context=None, timeout=None, source_address=None) A :class:`FTP` subclass which adds TLS support to FTP as described in :rfc:`4217`. @@ -80,10 +84,15 @@ The module defines the following items: private key and certificate chain file name for the SSL connection. *context* parameter is a :class:`ssl.SSLContext` object which allows bundling SSL configuration options, certificates and private keys into a - single (potentially long-lived) structure. + single (potentially long-lived) structure. *source_address* is a 2-tuple + ``(host, port)`` for the socket to bind to as its source address before + connecting. .. versionadded:: 3.2 + .. versionchanged:: 3.3 + *source_address* parameter was added. + Here's a sample session using the :class:`FTP_TLS` class: >>> from ftplib import FTP_TLS @@ -174,7 +183,7 @@ followed by ``lines`` for the text version or ``binary`` for the binary version. debugging output, logging each line sent and received on the control connection. -.. method:: FTP.connect(host='', port=0[, timeout]) +.. method:: FTP.connect(host='', port=0, timeout=None, source_address=None) 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 @@ -182,10 +191,14 @@ followed by ``lines`` for the text version or ``binary`` for the binary version. 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 no *timeout* is passed, the global default timeout setting will be used. + *source_address* is a 2-tuple ``(host, port)`` for the socket to bind to as + its source address before connecting. + + .. versionchanged:: 3.3 + *source_address* parameter was added. .. method:: FTP.getwelcome() diff --git a/Doc/library/getopt.rst b/Doc/library/getopt.rst index bcfc4b59c4..b6ab3df022 100644 --- a/Doc/library/getopt.rst +++ b/Doc/library/getopt.rst @@ -22,9 +22,6 @@ 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. -A more convenient, flexible, and powerful alternative is the -:mod:`optparse` module. - This module provides two functions and an exception: diff --git a/Doc/library/gzip.rst b/Doc/library/gzip.rst index 659a027648..59ea9d3432 100644 --- a/Doc/library/gzip.rst +++ b/Doc/library/gzip.rst @@ -72,7 +72,7 @@ The module defines the following items: :class:`GzipFile` supports the :class:`io.BufferedIOBase` interface, including iteration and the :keyword:`with` statement. Only the - :meth:`read1` and :meth:`truncate` methods aren't implemented. + :meth:`truncate` method isn't implemented. :class:`GzipFile` also provides the following method: @@ -94,6 +94,9 @@ The module defines the following items: .. versionchanged:: 3.2 Support for unseekable files was added. + .. versionchanged:: 3.3 + The :meth:`io.BufferedIOBase.read1` method is now implemented. + .. function:: open(filename, mode='rb', compresslevel=9) diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst index 757823d9f1..9cdad6ee85 100644 --- a/Doc/library/itertools.rst +++ b/Doc/library/itertools.rst @@ -46,7 +46,7 @@ Iterator Arguments Results ==================== ============================ ================================================= ============================================================= Iterator Arguments Results Example ==================== ============================ ================================================= ============================================================= -:func:`accumulate` p p0, p0+p1, p0+p1+p2, ... ``accumulate([1,2,3,4,5]) --> 1 3 6 10 15`` +:func:`accumulate` p [,func] p0, p0+p1, p0+p1+p2, ... ``accumulate([1,2,3,4,5]) --> 1 3 6 10 15`` :func:`chain` p, q, ... p0, p1, ... plast, q0, q1, ... ``chain('ABC', 'DEF') --> A B C D E F`` :func:`compress` data, selectors (d[0] if s[0]), (d[1] if s[1]), ... ``compress('ABCDEF', [1,0,1,0,1,1]) --> A C E F`` :func:`dropwhile` pred, seq seq[n], seq[n+1], starting when pred fails ``dropwhile(lambda x: x<5, [1,4,6,4,1]) --> 6 4 1`` @@ -84,23 +84,61 @@ 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:: accumulate(iterable) +.. function:: accumulate(iterable[, func]) Make an iterator that returns accumulated sums. Elements may be any addable - type including :class:`Decimal` or :class:`Fraction`. Equivalent to:: + type including :class:`Decimal` or :class:`Fraction`. If the optional + *func* argument is supplied, it should be a function of two arguments + and it will be used instead of addition. - def accumulate(iterable): + Equivalent to:: + + def accumulate(iterable, func=operator.add): 'Return running totals' # accumulate([1,2,3,4,5]) --> 1 3 6 10 15 + # accumulate([1,2,3,4,5], operator.mul) --> 1 2 6 24 120 it = iter(iterable) total = next(it) yield total for element in it: - total = total + element + total = func(total, element) yield total + There are a number of uses for the *func* argument. It can be set to + :func:`min` for a running minimum, :func:`max` for a running maximum, or + :func:`operator.mul` for a running product. Amortization tables can be + built by accumulating interest and applying payments. First-order + `recurrence relations <http://en.wikipedia.org/wiki/Recurrence_relation>`_ + can be modeled by supplying the initial value in the iterable and using only + the accumulated total in *func* argument:: + + >>> data = [3, 4, 6, 2, 1, 9, 0, 7, 5, 8] + >>> list(accumulate(data, operator.mul)) # running product + [3, 12, 72, 144, 144, 1296, 0, 0, 0, 0] + >>> list(accumulate(data, max)) # running maximum + [3, 4, 6, 6, 6, 9, 9, 9, 9, 9] + + # Amortize a 5% loan of 1000 with 4 annual payments of 90 + >>> cashflows = [1000, -90, -90, -90, -90] + >>> list(accumulate(cashflows, lambda bal, pmt: bal*1.05 + pmt)) + [1000, 960.0, 918.0, 873.9000000000001, 827.5950000000001] + + # Chaotic recurrence relation http://en.wikipedia.org/wiki/Logistic_map + >>> logistic_map = lambda x, _: r * x * (1 - x) + >>> r = 3.8 + >>> x0 = 0.4 + >>> inputs = repeat(x0, 36) # only the initial value is used + >>> [format(x, '.2f') for x in accumulate(inputs, logistic_map)] + ['0.40', '0.91', '0.30', '0.81', '0.60', '0.92', '0.29', '0.79', '0.63', + '0.88' ,'0.39', '0.90', '0.33', '0.84', '0.52', '0.95', '0.18', '0.57', + '0.93', '0.25', '0.71', '0.79', '0.63', '0.88', '0.39', '0.91', '0.32', + '0.83', '0.54', '0.95', '0.20', '0.60', '0.91', '0.30', '0.80', '0.60'] + .. versionadded:: 3.2 + .. versionchanged:: 3.3 + Added the optional *func* parameter. + .. function:: chain(*iterables) Make an iterator that returns elements from the first iterable until it is diff --git a/Doc/library/logging.handlers.rst b/Doc/library/logging.handlers.rst index eda93023d8..9346e9966c 100644 --- a/Doc/library/logging.handlers.rst +++ b/Doc/library/logging.handlers.rst @@ -838,6 +838,15 @@ possible, while any potentially slow operations (such as sending an email via Note that if you don't call this before your application exits, there may be some records still left on the queue, which won't be processed. + .. method:: enqueue_sentinel() + + Writes a sentinel to the queue to tell the listener to quit. This + implementation uses ``put_nowait()``. You may want to override this + method if you want to use timeouts or work with custom queue + implementations. + + .. versionadded:: 3.3 + .. seealso:: diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst index 32f762d506..eb2c7189a0 100644 --- a/Doc/library/logging.rst +++ b/Doc/library/logging.rst @@ -983,12 +983,27 @@ functions. | ``stream`` | Use the specified stream to initialize the | | | StreamHandler. Note that this argument is | | | incompatible with 'filename' - if both are | - | | present, 'stream' is ignored. | + | | present, a ``ValueError`` is raised. | + +--------------+---------------------------------------------+ + | ``handlers`` | If specified, this should be an iterable of | + | | already created handlers to add to the root | + | | logger. Any handlers which don't already | + | | have a formatter set will be assigned the | + | | default formatter created in this function. | + | | Note that this argument is incompatible | + | | with 'filename' or 'stream' - if both are | + | | present, a ``ValueError`` is raised. | +--------------+---------------------------------------------+ .. versionchanged:: 3.2 The ``style`` argument was added. + .. versionchanged:: 3.3 + The ``handlers`` argument was added. Additional checks were added to + catch situations where incompatible arguments are specified (e.g. + ``handlers`` together with ``stream`` or ``filename``, or ``stream`` + together with ``filename``). + .. function:: shutdown() diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst index 92d5272948..e1f43829f2 100644 --- a/Doc/library/multiprocessing.rst +++ b/Doc/library/multiprocessing.rst @@ -297,7 +297,7 @@ The :mod:`multiprocessing` package mostly replicates the API of the :class:`Process` and exceptions ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -.. class:: Process([group[, target[, name[, args[, kwargs]]]]]) +.. class:: Process([group[, target[, name[, args[, kwargs]]]]], *, daemon=None) Process objects represent activity that is run in a separate process. The :class:`Process` class has equivalents of all the methods of @@ -312,13 +312,19 @@ The :mod:`multiprocessing` package mostly replicates the API of the :sub:`1`,N\ :sub:`2`,...,N\ :sub:`k` is a sequence of integers whose length is determined by the *generation* of the process. *args* is the argument tuple for the target invocation. *kwargs* is a dictionary of keyword - arguments for the target invocation. By default, no arguments are passed to - *target*. + arguments for the target invocation. If provided, the keyword-only *daemon* argument + sets the process :attr:`daemon` flag to ``True`` or ``False``. If ``None`` + (the default), this flag will be inherited from the creating process. + + By default, no arguments are passed to *target*. If a subclass overrides the constructor, it must make sure it invokes the base class constructor (:meth:`Process.__init__`) before doing anything else to the process. + .. versionchanged:: 3.3 + Added the *daemon* argument. + .. method:: run() Method representing the process's activity. diff --git a/Doc/library/nntplib.rst b/Doc/library/nntplib.rst index 164f149096..13257cc362 100644 --- a/Doc/library/nntplib.rst +++ b/Doc/library/nntplib.rst @@ -70,10 +70,23 @@ The module itself defines the following classes: 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*. + :class:`NNTP` class supports the :keyword:`with` statement to + unconditionally consume :exc:`socket.error` exceptions and to close the NNTP + connection when done. Here is a sample on how using it: + + >>> from nntplib import NNTP + >>> with nntplib.NNTP('news.gmane.org') as n: + ... n.group('gmane.comp.python.committers') + ... + ('211 1454 1 1454 gmane.comp.python.committers', '1454', '1', '1454', 'gmane.comp.python.committers') + >>> + .. versionchanged:: 3.2 *usenetrc* is now False by default. + .. versionchanged:: 3.3 + Support for the :keyword:`with` statement was added. .. class:: NNTP_SSL(host, port=563, user=None, password=None, ssl_context=None, readermode=None, usenetrc=False, [timeout]) diff --git a/Doc/library/os.rst b/Doc/library/os.rst index fe785fc47c..eca51dcb8a 100644 --- a/Doc/library/os.rst +++ b/Doc/library/os.rst @@ -286,6 +286,22 @@ process and user. .. versionchanged:: 3.2 Added support for Windows. +.. function:: getpriority(which, who) + + .. index:: single: process; scheduling priority + + Get program scheduling priority. The value *which* is one of + :const:`PRIO_PROCESS`, :const:`PRIO_PGRP`, or :const:`PRIO_USER`, and *who* + is interpreted relative to *which* (a process identifier for + :const:`PRIO_PROCESS`, process group identifier for :const:`PRIO_PGRP`, and a + user ID for :const:`PRIO_USER`). A zero value for *who* denotes + (respectively) the calling process, the process group of the calling process, + or the real user ID of the calling process. + + Availability: Unix + + .. versionadded:: 3.3 + .. function:: getresuid() Return a tuple (ruid, euid, suid) denoting the current process's @@ -336,6 +352,15 @@ process and user. .. versionadded:: 3.2 +.. data:: PRIO_PROCESS + PRIO_PGRP + PRIO_USER + + Parameters for :func:`getpriority` and :func:`setpriority` functions. + + Availability: Unix. + + .. versionadded:: 3.3 .. function:: putenv(key, value) @@ -405,6 +430,25 @@ process and user. Availability: Unix. +.. function:: setpriority(which, who, priority) + + .. index:: single: process; scheduling priority + + Set program scheduling priority. The value *which* is one of + :const:`PRIO_PROCESS`, :const:`PRIO_PGRP`, or :const:`PRIO_USER`, and *who* + is interpreted relative to *which* (a process identifier for + :const:`PRIO_PROCESS`, process group identifier for :const:`PRIO_PGRP`, and a + user ID for :const:`PRIO_USER`). A zero value for *who* denotes + (respectively) the calling process, the process group of the calling process, + or the real user ID of the calling process. + *priority* is a value in the range -20 to 19. The default priority is 0; + lower priorities cause more favorable scheduling. + + Availability: Unix + + .. versionadded:: 3.3 + + .. function:: setregid(rgid, egid) Set the current process's real and effective group ids. @@ -562,6 +606,21 @@ associated with a :term:`file object` when required. Note that using the file descriptor directly will bypass the file object methods, ignoring aspects such as internal buffering of data. +.. data:: AT_SYMLINK_NOFOLLOW + AT_EACCESS + AT_FDCWD + AT_REMOVEDIR + AT_SYMLINK_FOLLOW + UTIME_NOW + UTIME_OMIT + + These parameters are used as flags to the \*at family of functions. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: close(fd) Close file descriptor *fd*. @@ -610,6 +669,19 @@ as internal buffering of data. Availability: Unix, Windows. +.. function:: faccessat(dirfd, path, mode, flags=0) + + Like :func:`access` but if *path* is relative, it is taken as relative to *dirfd*. + *flags* is optional and can be constructed by ORing together zero or more + of these values: :data:`AT_SYMLINK_NOFOLLOW`, :data:`AT_EACCESS`. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: fchmod(fd, mode) Change the mode of the file given by *fd* to the numeric *mode*. See the docs @@ -618,6 +690,18 @@ as internal buffering of data. Availability: Unix. +.. function:: fchmodat(dirfd, path, mode, flags=0) + + Like :func:`chmod` but if *path* is relative, it is taken as relative to *dirfd*. + *flags* is optional and may be 0 or :data:`AT_SYMLINK_NOFOLLOW`. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: fchown(fd, uid, gid) Change the owner and group id of the file given by *fd* to the numeric *uid* @@ -626,6 +710,18 @@ as internal buffering of data. Availability: Unix. +.. function:: fchownat(dirfd, path, uid, gid, flags=0) + + Like :func:`chown` but if *path* is relative, it is taken as relative to *dirfd*. + *flags* is optional and may be 0 or :data:`AT_SYMLINK_NOFOLLOW`. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: fdatasync(fd) Force write of file with filedescriptor *fd* to disk. Does not force update of @@ -637,6 +733,27 @@ as internal buffering of data. This function is not available on MacOS. +.. function:: fdlistdir(fd) + + Like :func:`listdir`, but uses a file descriptor instead and always returns + strings. After execution of this function, *fd* will be closed. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: fexecve(fd, args, env) + + Execute the program specified by a file descriptor *fd* with arguments given + by *args* and environment given by *env*, replacing the current process. + *args* and *env* are given as in :func:`execve`. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: fpathconf(fd, name) Return system configuration information relevant to an open file. *name* @@ -661,6 +778,17 @@ as internal buffering of data. Availability: Unix, Windows. +.. function:: fstatat(dirfd, path, flags=0) + + Like :func:`stat` but if *path* is relative, it is taken as relative to *dirfd*. + *flags* is optional and may be 0 or :data:`AT_SYMLINK_NOFOLLOW`. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + .. function:: fstatvfs(fd) @@ -690,6 +818,57 @@ as internal buffering of data. Availability: Unix. +.. function:: futimesat(dirfd, path, (atime, mtime)) + futimesat(dirfd, path, None) + + Like :func:`utime` but if *path* is relative, it is taken as relative to *dirfd*. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: futimens(fd, (atime_sec, atime_nsec), (mtime_sec, mtime_nsec)) + futimens(fd, None, None) + + Updates the timestamps of a file specified by the file descriptor *fd*, with + nanosecond precision. + The second form sets *atime* and *mtime* to the current time. + If *atime_nsec* or *mtime_nsec* is specified as :data:`UTIME_NOW`, the corresponding + timestamp is updated to the current time. + If *atime_nsec* or *mtime_nsec* is specified as :data:`UTIME_OMIT`, the corresponding + timestamp is not updated. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. data:: UTIME_NOW + UTIME_OMIT + + Flags used with :func:`futimens` to specify that the timestamp must be + updated either to the current time or not updated at all. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: futimes(fd, (atime, mtime)) + futimes(fd, None) + + Set the access and modified time of the file specified by the file + descriptor *fd* to the given values. If the second form is used, set the + access and modified times to the current time. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: isatty(fd) Return ``True`` if the file descriptor *fd* is open and connected to a @@ -698,6 +877,44 @@ as internal buffering of data. Availability: Unix. +.. function:: linkat(srcfd, srcpath, dstfd, dstpath, flags=0) + + Like :func:`link` but if *srcpath* is relative, it is taken as relative to *srcfd* + and if *dstpath* is relative, it is taken as relative to *dstfd*. + *flags* is optional and may be 0 or :data:`AT_SYMLINK_FOLLOW`. + If *srcpath* is relative and *srcfd* is the special value :data:`AT_FDCWD`, then + *srcpath* is interpreted relative to the current working directory. This + also applies for *dstpath*. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: lockf(fd, cmd, len) + + Apply, test or remove a POSIX lock on an open file descriptor. + *fd* is an open file descriptor. + *cmd* specifies the command to use - one of :data:`F_LOCK`, :data:`F_TLOCK`, + :data:`F_ULOCK` or :data:`F_TEST`. + *len* specifies the section of the file to lock. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. data:: F_LOCK + F_TLOCK + F_ULOCK + F_TEST + + Flags that specify what action :func:`lockf` will take. + + Availability: Unix. + + .. versionadded:: 3.3 + .. function:: lseek(fd, pos, how) Set the current position of file descriptor *fd* to position *pos*, modified @@ -717,6 +934,39 @@ as internal buffering of data. respectively. Availability: Windows, Unix. +.. function:: mkdirat(dirfd, path, mode=0o777) + + Like :func:`mkdir` but if *path* is relative, it is taken as relative to *dirfd*. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: mkfifoat(dirfd, path, mode=0o666) + + Like :func:`mkfifo` but if *path* is relative, it is taken as relative to *dirfd*. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: mknodat(dirfd, path, mode=0o600, device=0) + + Like :func:`mknod` but if *path* is relative, it is taken as relative to *dirfd*. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: open(file, flags[, mode]) Open the file *file* and set various flags according to *flags* and possibly @@ -739,6 +989,17 @@ as internal buffering of data. wrap a file descriptor in a file object, use :func:`fdopen`. +.. function:: openat(dirfd, path, flags, mode=0o777) + + Like :func:`open` but if *path* is relative, it is taken as relative to *dirfd*. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: openpty() .. index:: module: pty @@ -758,6 +1019,66 @@ as internal buffering of data. Availability: Unix, Windows. +.. function:: posix_fallocate(fd, offset, len) + + Ensures that enough disk space is allocated for the file specified by *fd* + starting from *offset* and continuing for *len* bytes. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: posix_fadvise(fd, offset, len, advice) + + Announces an intention to access data in a specific pattern thus allowing + the kernel to make optimizations. + The advice applies to the region of the file specified by *fd* starting at + *offset* and continuing for *len* bytes. + *advice* is one of :data:`POSIX_FADV_NORMAL`, :data:`POSIX_FADV_SEQUENTIAL`, + :data:`POSIX_FADV_RANDOM`, :data:`POSIX_FADV_NOREUSE`, + :data:`POSIX_FADV_WILLNEED` or :data:`POSIX_FADV_DONTNEED`. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. data:: POSIX_FADV_NORMAL + POSIX_FADV_SEQUENTIAL + POSIX_FADV_RANDOM + POSIX_FADV_NOREUSE + POSIX_FADV_WILLNEED + POSIX_FADV_DONTNEED + + Flags that can be used in *advice* in :func:`posix_fadvise` that specify + the access pattern that is likely to be used. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: pread(fd, buffersize, offset) + + Read from a file descriptor, *fd*, at a position of *offset*. It will read up + to *buffersize* number of bytes. The file offset remains unchanged. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: pwrite(fd, string, offset) + + Write *string* to a file descriptor, *fd*, from *offset*, leaving the file + offset unchanged. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: read(fd, n) Read at most *n* bytes from file descriptor *fd*. Return a bytestring containing the @@ -775,6 +1096,93 @@ as internal buffering of data. :meth:`~file.readline` methods. +.. function:: sendfile(out, in, offset, nbytes) + sendfile(out, in, offset, nbytes, headers=None, trailers=None, flags=0) + + Copy *nbytes* bytes from file descriptor *in* to file descriptor *out* + starting at *offset*. + Return the number of bytes sent. When EOF is reached return 0. + + The first function notation is supported by all platforms that define + :func:`sendfile`. + + On Linux, if *offset* is given as ``None``, the bytes are read from the + current position of *in* and the position of *in* is updated. + + The second case may be used on Mac OS X and FreeBSD where *headers* and + *trailers* are arbitrary sequences of buffers that are written before and + after the data from *in* is written. It returns the same as the first case. + + On Mac OS X and FreeBSD, a value of 0 for *nbytes* specifies to send until + the end of *in* is reached. + + On Solaris, *out* may be the file descriptor of a regular file or the file + descriptor of a socket. On all other platforms, *out* must be the file + descriptor of an open socket. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. data:: SF_NODISKIO + SF_MNOWAIT + SF_SYNC + + Parameters to the :func:`sendfile` function, if the implementation supports + them. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: readlinkat(dirfd, path) + + Like :func:`readlink` but if *path* is relative, it is taken as relative to *dirfd*. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: renameat(olddirfd, oldpath, newdirfd, newpath) + + Like :func:`rename` but if *oldpath* is relative, it is taken as relative to + *olddirfd* and if *newpath* is relative, it is taken as relative to *newdirfd*. + If *oldpath* is relative and *olddirfd* is the special value :data:`AT_FDCWD`, then + *oldpath* is interpreted relative to the current working directory. This + also applies for *newpath*. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: symlinkat(src, dstfd, dst) + + Like :func:`symlink` but if *dst* is relative, it is taken as relative to *dstfd*. + If *dst* is relative and *dstfd* is the special value :data:`AT_FDCWD`, then *dst* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: readv(fd, buffers) + + Read from a file descriptor into a number of writable buffers. *buffers* is + an arbitrary sequence of writable buffers. Returns the total number of bytes + read. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: tcgetpgrp(fd) Return the process group associated with the terminal given by *fd* (an open @@ -800,6 +1208,38 @@ as internal buffering of data. Availability: Unix. +.. function:: unlinkat(dirfd, path, flags=0) + + Like :func:`unlink` but if *path* is relative, it is taken as relative to *dirfd*. + *flags* is optional and may be 0 or :data:`AT_REMOVEDIR`. If :data:`AT_REMOVEDIR` is + specified, :func:`unlinkat` behaves like :func:`rmdir`. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: utimensat(dirfd, path, (atime_sec, atime_nsec), (mtime_sec, mtime_nsec), flags) + utimensat(dirfd, path, None, None, flags) + + Updates the timestamps of a file with nanosecond precision. + The second form sets *atime* and *mtime* to the current time. + If *atime_nsec* or *mtime_nsec* is specified as :data:`UTIME_NOW`, the corresponding + timestamp is updated to the current time. + If *atime_nsec* or *mtime_nsec* is specified as :data:`UTIME_OMIT`, the corresponding + timestamp is not updated. + If *path* is relative, it is taken as relative to *dirfd*. + *flags* is optional and may be 0 or :data:`AT_SYMLINK_NOFOLLOW`. + If *path* is relative and *dirfd* is the special value :data:`AT_FDCWD`, then *path* + is interpreted relative to the current working directory. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: write(fd, str) Write the bytestring in *str* to file descriptor *fd*. Return the number of @@ -816,6 +1256,17 @@ as internal buffering of data. :meth:`~file.write` method. +.. function:: writev(fd, buffers) + + Write the the contents of *buffers* to file descriptor *fd*, where *buffers* + is an arbitrary sequence of buffers. + Returns the total number of bytes written. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. _open-constants: ``open()`` flag constants @@ -1089,6 +1540,17 @@ Files and Directories Added support for Windows 6.0 (Vista) symbolic links. +.. function:: lutimes(path, (atime, mtime)) + lutimes(path, None) + + Like :func:`utime`, but if *path* is a symbolic link, it is not + dereferenced. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: mkfifo(path[, mode]) Create a FIFO (a named pipe) named *path* with numeric mode *mode*. The @@ -1432,6 +1894,25 @@ Files and Directories Added support for Windows 6.0 (Vista) symbolic links. +.. function:: sync() + + Force write of everything to disk. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. function:: truncate(path, length) + + Truncate the file corresponding to *path*, so that it is at most + *length* bytes in size. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. function:: unlink(path) Remove (delete) the file *path*. This is the same function as @@ -2011,6 +2492,58 @@ written in Python, such as a mail server's external command delivery program. Availability: Unix. +.. function:: waitid(idtype, id, options) + + Wait for the completion of one or more child processes. + *idtype* can be :data:`P_PID`, :data:`P_PGID` or :data:`P_ALL`. + *id* specifies the pid to wait on. + *options* is constructed from the ORing of one or more of :data:`WEXITED`, + :data:`WSTOPPED` or :data:`WCONTINUED` and additionally may be ORed with + :data:`WNOHANG` or :data:`WNOWAIT`. The return value is an object + representing the data contained in the :c:type:`siginfo_t` structure, namely: + :attr:`si_pid`, :attr:`si_uid`, :attr:`si_signo`, :attr:`si_status`, + :attr:`si_code` or ``None`` if :data:`WNOHANG` is specified and there are no + children in a waitable state. + + Availability: Unix. + + .. versionadded:: 3.3 + +.. data:: P_PID + P_PGID + P_ALL + + These are the possible values for *idtype* in :func:`waitid`. They affect + how *id* is interpreted. + + Availability: Unix. + + .. versionadded:: 3.3 + +.. data:: WEXITED + WSTOPPED + WNOWAIT + + Flags that can be used in *options* in :func:`waitid` that specify what + child signal to wait for. + + Availability: Unix. + + .. versionadded:: 3.3 + + +.. data:: CLD_EXITED + CLD_DUMPED + CLD_TRAPPED + CLD_CONTINUED + + These are the possible values for :attr:`si_code` in the result returned by + :func:`waitid`. + + Availability: Unix. + + .. versionadded:: 3.3 + .. function:: waitpid(pid, options) diff --git a/Doc/library/platform.rst b/Doc/library/platform.rst index b0431d96f1..76256aa86c 100644 --- a/Doc/library/platform.rst +++ b/Doc/library/platform.rst @@ -214,6 +214,10 @@ Win95/98 specific 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. + .. deprecated:: 3.3 + This function is obsolete. Use the :mod:`subprocess` module. Check + especially the :ref:`subprocess-replacements` section. + Mac OS Platform --------------- diff --git a/Doc/library/re.rst b/Doc/library/re.rst index 3e9cf026f0..b1c3804b67 100644 --- a/Doc/library/re.rst +++ b/Doc/library/re.rst @@ -689,9 +689,12 @@ form. .. 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. + Escape all the characters in pattern except ASCII letters, numbers and ``'_'``. + This is useful if you want to match an arbitrary literal string that may + have regular expression metacharacters in it. + + .. versionchanged:: 3.3 + The ``'_'`` character is no longer escaped. .. function:: purge() diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst index 698b1e74f4..ffe7f09d48 100644 --- a/Doc/library/signal.rst +++ b/Doc/library/signal.rst @@ -13,9 +13,6 @@ rules for working with signals and their handlers: 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 @@ -119,6 +116,28 @@ The variables defined in the :mod:`signal` module are: in user and kernel space. SIGPROF is delivered upon expiration. +.. data:: SIG_BLOCK + + A possible value for the *how* parameter to :func:`pthread_sigmask` + indicating that signals are to be blocked. + + .. versionadded:: 3.3 + +.. data:: SIG_UNBLOCK + + A possible value for the *how* parameter to :func:`pthread_sigmask` + indicating that signals are to be unblocked. + + .. versionadded:: 3.3 + +.. data:: SIG_SETMASK + + A possible value for the *how* parameter to :func:`pthread_sigmask` + indicating that the signal mask is to be replaced. + + .. versionadded:: 3.3 + + The :mod:`signal` module defines one exception: .. exception:: ItimerError @@ -161,6 +180,34 @@ The :mod:`signal` module defines the following functions: :manpage:`signal(2)`.) +.. function:: pthread_sigmask(how, mask) + + Fetch and/or change the signal mask of the calling thread. The signal mask + is the set of signals whose delivery is currently blocked for the caller. + The old signal mask is returned. + + The behavior of the call is dependent on the value of *how*, as follows. + + * :data:`SIG_BLOCK`: The set of blocked signals is the union of the current + set and the *mask* argument. + * :data:`SIG_UNBLOCK`: The signals in *mask* are removed from the current + set of blocked signals. It is permissible to attempt to unblock a + signal which is not blocked. + * :data:`SIG_SETMASK`: The set of blocked signals is set to the *mask* + argument. + + *mask* is a list of signal numbers (e.g. [:const:`signal.SIGINT`, + :const:`signal.SIGTERM`]). + + For example, ``signal.pthread_sigmask(signal.SIG_BLOCK, [])`` reads the + signal mask of the calling thread. + + Availability: Unix. See the man page :manpage:`sigprocmask(3)` and + :manpage:`pthread_sigmask(3)` for further information. + + .. versionadded:: 3.3 + + .. function:: setitimer(which, seconds[, interval]) Sets given interval timer (one of :const:`signal.ITIMER_REAL`, diff --git a/Doc/library/site.rst b/Doc/library/site.rst index b77f3cf02d..23ce46504f 100644 --- a/Doc/library/site.rst +++ b/Doc/library/site.rst @@ -13,7 +13,15 @@ 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. +Importing this module will append site-specific paths to the module search +path, unless :option:`-S` was used. In that case, this module can be safely +imported with no automatic modifications to the module search path. To +explicitly trigger the usual site-specific additions, call the +:func:`site.main` function. + +.. versionchanged:: 3.3 + Importing the module used to trigger paths manipulation even when using + :option:`-S`. .. index:: pair: site-python; directory @@ -114,6 +122,13 @@ empty, and the path manipulations are skipped; however the import of .. envvar:: PYTHONUSERBASE +.. function:: main() + + Adds all the standard site-specific directories to the module search + path. This function is called automatically when this module is imported, + unless the :program:`python` interpreter was started with the :option:`-S` + flag. + .. function:: addsitedir(sitedir, known_paths=None) Adds a directory to sys.path and processes its pth files. diff --git a/Doc/library/smtplib.rst b/Doc/library/smtplib.rst index 531a64d73f..cfd5018a99 100644 --- a/Doc/library/smtplib.rst +++ b/Doc/library/smtplib.rst @@ -34,6 +34,20 @@ Protocol) and :rfc:`1869` (SMTP Service Extensions). For normal use, you should only require the initialization/connect, :meth:`sendmail`, and :meth:`quit` methods. An example is included below. + The :class:`SMTP` class supports the :keyword:`with` statement. When used + like this, the SMTP ``QUIT`` command is issued automatically when the + :keyword:`with` statement exits. E.g.:: + + >>> from smtplib import SMTP + >>> with SMTP("domain.org") as smtp: + ... smtp.noop() + ... + (250, b'Ok') + >>> + + .. versionchanged:: 3.3 + Support for the :keyword:`with` statement was added. + .. class:: SMTP_SSL(host='', port=0, local_hostname=None, keyfile=None, certfile=None[, timeout]) diff --git a/Doc/library/socket.rst b/Doc/library/socket.rst index bfb8ae9414..65533df2cd 100644 --- a/Doc/library/socket.rst +++ b/Doc/library/socket.rst @@ -526,6 +526,16 @@ The module :mod:`socket` exports the following constants and functions: meanings. +.. function:: sethostname(name) + + Set the machine's hostname to *name*. This will raise a + :exc:`socket.error` if you don't have enough rights. + + Availability: Unix. + + .. versionadded:: 3.3 + + .. data:: SocketType This is a Python type object that represents the socket object type. It is the diff --git a/Doc/library/sqlite3.rst b/Doc/library/sqlite3.rst index 7367674430..01c306c6d6 100644 --- a/Doc/library/sqlite3.rst +++ b/Doc/library/sqlite3.rst @@ -369,6 +369,22 @@ Connection Objects method with :const:`None` for *handler*. +.. method:: Connection.set_trace_callback(trace_callback) + + Registers *trace_callback* to be called for each SQL statement that is + actually executed by the SQLite backend. + + The only argument passed to the callback is the statement (as string) that + is being executed. The return value of the callback is ignored. Note that + the backend does not only run statements passed to the :meth:`Cursor.execute` + methods. Other sources include the transaction management of the Python + module and the execution of triggers defined in the current database. + + Passing :const:`None` as *trace_callback* will disable the trace callback. + + .. versionadded:: 3.3 + + .. method:: Connection.enable_load_extension(enabled) This routine allows/disallows the SQLite engine to load SQLite extensions diff --git a/Doc/library/ssl.rst b/Doc/library/ssl.rst index 011d37806f..a20cabcc9f 100644 --- a/Doc/library/ssl.rst +++ b/Doc/library/ssl.rst @@ -239,6 +239,9 @@ Certificate handling will attempt to validate the server certificate against that set of root certificates, and will fail if the validation attempt fails. + .. versionchanged:: 3.3 + This function is now IPv6-compatible. + .. function:: DER_cert_to_PEM_cert(DER_cert_bytes) Given a certificate as a DER-encoded blob of bytes, returns a PEM-encoded diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst index e3c8b151cd..c0c75f7f91 100644 --- a/Doc/library/stdtypes.rst +++ b/Doc/library/stdtypes.rst @@ -1652,6 +1652,8 @@ Note that while lists allow their items to be of any type, bytearray object single: append() (sequence method) single: extend() (sequence method) single: count() (sequence method) + single: clear() (sequence method) + single: copy() (sequence method) single: index() (sequence method) single: insert() (sequence method) single: pop() (sequence method) @@ -1683,6 +1685,12 @@ Note that while lists allow their items to be of any type, bytearray object | ``s.extend(x)`` | same as ``s[len(s):len(s)] = | \(2) | | | x`` | | +------------------------------+--------------------------------+---------------------+ +| ``s.clear()`` | remove all items from ``s`` | | +| | | | ++------------------------------+--------------------------------+---------------------+ +| ``s.copy()`` | return a shallow copy of ``s`` | | +| | | | ++------------------------------+--------------------------------+---------------------+ | ``s.count(x)`` | return number of *i*'s for | | | | which ``s[i] == x`` | | +------------------------------+--------------------------------+---------------------+ @@ -1761,6 +1769,9 @@ Notes: (8) :meth:`sort` is not supported by :class:`bytearray` objects. + .. versionadded:: 3.3 + :meth:`clear` and :meth:`!copy` methods. + .. _bytes-methods: diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst index e09994ce7d..bb4884903c 100644 --- a/Doc/library/subprocess.rst +++ b/Doc/library/subprocess.rst @@ -123,12 +123,14 @@ This module defines one class called :class:`Popen`: *stdin*, *stdout* and *stderr* specify the executed programs' standard input, standard output and standard error file handles, respectively. Valid values - are :data:`PIPE`, an existing file descriptor (a positive integer), an - existing :term:`file object`, and ``None``. :data:`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 :data:`STDOUT`, which indicates that the stderr data from the - applications should be captured into the same file handle as for stdout. + are :data:`PIPE`, :data:`DEVNULL`, an existing file descriptor (a positive + integer), an existing :term:`file object`, and ``None``. :data:`PIPE` + indicates that a new pipe to the child should be created. :data:`DEVNULL` + indicates that the special file :data:`os.devnull` will be used. With ``None``, + no redirection will occur; the child's file handles will be inherited from + the parent. Additionally, *stderr* can be :data:`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. @@ -228,6 +230,15 @@ This module defines one class called :class:`Popen`: Added context manager support. +.. data:: DEVNULL + + Special value that can be used as the *stdin*, *stdout* or *stderr* argument + to :class:`Popen` and indicates that the special file :data:`os.devnull` + will be used. + + .. versionadded:: 3.3 + + .. data:: PIPE Special value that can be used as the *stdin*, *stdout* or *stderr* argument @@ -248,15 +259,21 @@ Convenience Functions This module also defines the following shortcut functions: -.. function:: call(*popenargs, **kwargs) +.. function:: call(*popenargs, timeout=None, **kwargs) Run command with arguments. Wait for command to complete, then return the :attr:`returncode` attribute. - The arguments are the same as for the :class:`Popen` constructor. Example:: + The arguments are the same as for the :class:`Popen` constructor, with the + exception of the *timeout* argument, which is given to :meth:`Popen.wait`. + Example:: >>> retcode = subprocess.call(["ls", "-l"]) + If the timeout expires, the child process will be killed and then waited for + again. The :exc:`TimeoutExpired` exception will be re-raised after the child + process has terminated. + .. warning:: Like :meth:`Popen.wait`, this will deadlock when using @@ -264,34 +281,43 @@ This module also defines the following shortcut functions: generates enough output to a pipe such that it blocks waiting for the OS pipe buffer to accept more data. + .. versionchanged:: 3.3 + *timeout* was added. + -.. function:: check_call(*popenargs, **kwargs) +.. function:: check_call(*popenargs, timeout=None, **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 :class:`Popen` constructor. Example:: + The arguments are the same as for the :func:`call` function. Example:: >>> subprocess.check_call(["ls", "-l"]) 0 + As in the :func:`call` function, if the timeout expires, the child process + will be killed and the wait retried. The :exc:`TimeoutExpired` exception + will be re-raised after the child process has terminated. + .. warning:: See the warning for :func:`call`. + .. versionchanged:: 3.3 + *timeout* was added. -.. function:: check_output(*popenargs, **kwargs) + +.. function:: check_output(*popenargs, timeout=None, **kwargs) Run command with arguments and return its output as a byte string. If the exit code was non-zero it raises a :exc:`CalledProcessError`. The :exc:`CalledProcessError` object will have the return code in the - :attr:`returncode` - attribute and output in the :attr:`output` attribute. + :attr:`returncode` attribute and output in the :attr:`output` attribute. - The arguments are the same as for the :class:`Popen` constructor. Example:: + The arguments are the same as for the :func:`call` function. Example:: >>> subprocess.check_output(["ls", "-l", "/dev/null"]) b'crw-rw-rw- 1 root root 1, 3 Oct 18 2007 /dev/null\n' @@ -304,8 +330,17 @@ This module also defines the following shortcut functions: ... stderr=subprocess.STDOUT) b'ls: non_existent_file: No such file or directory\n' + As in the :func:`call` function, if the timeout expires, the child process + will be killed and the wait retried. The :exc:`TimeoutExpired` exception + will be re-raised after the child process has terminated. The output from + the child process so far will be in the :attr:`output` attribute of the + exception. + .. versionadded:: 3.1 + .. versionchanged:: 3.3 + *timeout* was added. + .. function:: getstatusoutput(cmd) @@ -358,6 +393,15 @@ arguments. check_call() will raise :exc:`CalledProcessError`, if the called process returns a non-zero return code. +All of the functions and methods that accept a *timeout* parameter, such as +:func:`call` and :meth:`Popen.communicate` will raise :exc:`TimeoutExpired` if +the timeout expires before the process exits. + +Exceptions defined in this module all inherit from :exc:`SubprocessError`. + + .. versionadded:: 3.3 + The :exc:`SubprocessError` base class was added. + Security ^^^^^^^^ @@ -379,11 +423,15 @@ Instances of the :class:`Popen` class have the following methods: attribute. -.. method:: Popen.wait() +.. method:: Popen.wait(timeout=None) Wait for child process to terminate. Set and return :attr:`returncode` attribute. + If the process does not terminate after *timeout* seconds, raise a + :exc:`TimeoutExpired` exception. It is safe to catch this exception and + retry the wait. + .. warning:: This will deadlock when using ``stdout=PIPE`` and/or @@ -391,11 +439,14 @@ Instances of the :class:`Popen` class have the following methods: a pipe such that it blocks waiting for the OS pipe buffer to accept more data. Use :meth:`communicate` to avoid that. + .. versionchanged:: 3.3 + *timeout* was added. -.. method:: Popen.communicate(input=None) + +.. method:: Popen.communicate(input=None, timeout=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 + until end-of-file is reached. Wait for process to terminate. The optional *input* argument should be a byte string to be sent to the child process, or ``None``, if no data should be sent to the child. @@ -406,11 +457,29 @@ Instances of the :class:`Popen` class have the following methods: ``None`` in the result tuple, you need to give ``stdout=PIPE`` and/or ``stderr=PIPE`` too. + If the process does not terminate after *timeout* seconds, a + :exc:`TimeoutExpired` exception will be raised. Catching this exception and + retrying communication will not lose any output. + + The child process is not killed if the timeout expires, so in order to + cleanup properly a well-behaved application should kill the child process and + finish communication:: + + proc = subprocess.Popen(...) + try: + outs, errs = proc.communicate(timeout=15) + except TimeoutExpired: + proc.kill() + outs, errs = proc.communicate() + .. note:: The data read is buffered in memory, so do not use this method if the data size is large or unlimited. + .. versionchanged:: 3.3 + *timeout* was added. + .. method:: Popen.send_signal(signal) diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index 006905262b..2bcf95847c 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -36,18 +36,6 @@ always available. little-endian (least-significant byte first) platforms. -.. 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``. - - .. data:: builtin_module_names A tuple of strings giving the names of all modules that are compiled into this @@ -236,14 +224,13 @@ always available. .. data:: flags - The struct sequence *flags* exposes the status of command line flags. The - attributes are read only. + The :term:`struct sequence` *flags* exposes the status of command line + flags. The attributes are read only. ============================= ============================= attribute flag ============================= ============================= :const:`debug` :option:`-d` - :const:`division_warning` :option:`-Q` :const:`inspect` :option:`-i` :const:`interactive` :option:`-i` :const:`optimize` :option:`-O` or :option:`-OO` @@ -259,15 +246,18 @@ always available. .. versionchanged:: 3.2 Added ``quiet`` attribute for the new :option:`-q` flag. + .. versionchanged:: 3.3 + Removed obsolete ``division_warning`` attribute. + .. data:: float_info - A structseq holding information about the float type. It contains low level - information about the precision and internal representation. The values - correspond to the various floating-point constants defined in the standard - header file :file:`float.h` for the 'C' programming language; see section - 5.2.4.2.2 of the 1999 ISO/IEC C standard [C99]_, 'Characteristics of - floating types', for details. + A :term:`struct sequence` holding information about the float type. It + contains low level information about the precision and internal + representation. The values correspond to the various floating-point + constants defined in the standard header file :file:`float.h` for the 'C' + programming language; see section 5.2.4.2.2 of the 1999 ISO/IEC C standard + [C99]_, 'Characteristics of floating types', for details. +---------------------+----------------+--------------------------------------------------+ | attribute | float.h macro | explanation | @@ -513,8 +503,9 @@ always available. .. data:: hash_info - A structseq giving parameters of the numeric hash implementation. For - more details about hashing of numeric types, see :ref:`numeric-hash`. + A :term:`struct sequence` giving parameters of the numeric hash + implementation. For more details about hashing of numeric types, see + :ref:`numeric-hash`. +---------------------+--------------------------------------------------+ | attribute | explanation | @@ -549,8 +540,8 @@ always available. 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 - struct sequence :data:`sys.version_info` may be used for a more human-friendly - encoding of the same information. + :term:`struct sequence` :data:`sys.version_info` may be used for a more + human-friendly encoding of the same information. The ``hexversion`` is a 32-bit number with the following layout: @@ -578,8 +569,8 @@ always available. .. data:: int_info - A struct sequence that holds information about Python's - internal representation of integers. The attributes are read only. + A :term:`struct sequence` that holds information about Python's internal + representation of integers. The attributes are read only. +-------------------------+----------------------------------------------+ | Attribute | Explanation | @@ -970,6 +961,35 @@ always available. to a console and Python apps started with :program:`pythonw`. +.. data:: thread_info + + A :term:`struct sequence` holding information about the thread + implementation. + + +------------------+---------------------------------------------------------+ + | Attribute | Explanation | + +==================+=========================================================+ + | :const:`name` | Name of the thread implementation: | + | | | + | | * ``'nt'``: Windows threads | + | | * ``'os2'``: OS/2 threads | + | | * ``'pthread'``: POSIX threads | + | | * ``'solaris'``: Solaris threads | + +------------------+---------------------------------------------------------+ + | :const:`lock` | Name of the lock implementation: | + | | | + | | * ``'semaphore'``: a lock uses a semaphore | + | | * ``'mutex+cond'``: a lock uses a mutex | + | | and a condition variable | + | | * ``None`` if this information is unknown | + +------------------+---------------------------------------------------------+ + | :const:`version` | Name and version of the thread library. It is a string, | + | | or ``None`` if these informations are unknown. | + +------------------+---------------------------------------------------------+ + + .. versionadded:: 3.3 + + .. data:: tracebacklimit When this variable is set to an integer value, it determines the maximum number diff --git a/Doc/library/threading.rst b/Doc/library/threading.rst index 5f1b9bfb06..df47045ffb 100644 --- a/Doc/library/threading.rst +++ b/Doc/library/threading.rst @@ -20,17 +20,6 @@ The :mod:`dummy_threading` module is provided for situations where methods and functions in this module in the Python 2.x series are still supported by this module. -.. impl-detail:: - - Due to the :term:`Global Interpreter Lock`, in CPython only one thread - can execute Python code at once (even though certain performance-oriented - libraries might overcome this limitation). - If you want your application to make better of use of the computational - resources of multi-core machines, you are advised to use - :mod:`multiprocessing` or :class:`concurrent.futures.ProcessPoolExecutor`. - However, threading is still an appropriate model if you want to run - multiple I/O-bound tasks simultaneously. - This module defines the following functions and objects: @@ -241,7 +230,7 @@ changed through the :attr:`name` attribute. 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 -through the :attr:`daemon` property. +through the :attr:`daemon` property or the *daemon* constructor argument. There is a "main thread" object; this corresponds to the initial thread of control in the Python program. It is not a daemon thread. @@ -254,7 +243,8 @@ 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={}) +.. class:: Thread(group=None, target=None, name=None, args=(), kwargs={}, + verbose=None, *, daemon=None) This constructor should always be called with keyword arguments. Arguments are: @@ -273,10 +263,19 @@ impossible to detect the termination of alien threads. *kwargs* is a dictionary of keyword arguments for the target invocation. Defaults to ``{}``. + *verbose* is a flag used for debugging messages. + + If not ``None``, *daemon* explicitly sets whether the thread is daemonic. + If ``None`` (the default), the daemonic property is inherited from the + current thread. + 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. + .. versionchanged:: 3.3 + Added the *daemon* argument. + .. method:: start() Start the thread's activity. @@ -364,6 +363,18 @@ impossible to detect the termination of alien threads. property instead. +.. impl-detail:: + + Due to the :term:`Global Interpreter Lock`, in CPython only one thread + can execute Python code at once (even though certain performance-oriented + libraries might overcome this limitation). + If you want your application to make better of use of the computational + resources of multi-core machines, you are advised to use + :mod:`multiprocessing` or :class:`concurrent.futures.ProcessPoolExecutor`. + However, threading is still an appropriate model if you want to run + multiple I/O-bound tasks simultaneously. + + .. _lock-objects: Lock Objects diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst index beed4ded86..a623f3c57a 100644 --- a/Doc/library/unittest.rst +++ b/Doc/library/unittest.rst @@ -723,7 +723,7 @@ Test cases Here, we create two instances of :class:`WidgetTestCase`, each of which runs a single test. - .. versionchanged:: + .. versionchanged:: 3.2 `TestCase` can be instantiated successfully without providing a method name. This makes it easier to experiment with `TestCase` from the interactive interpreter. @@ -792,11 +792,14 @@ Test cases Run the test, collecting the result into the test result object passed as *result*. If *result* is omitted or ``None``, a temporary result object is created (by calling the :meth:`defaultTestResult` method) and - used. The result object is not returned to :meth:`run`'s caller. + used. The result object is returned to :meth:`run`'s caller. The same effect may be had by simply calling the :class:`TestCase` instance. + .. versionchanged:: 3.3 + Previous versions of ``run`` did not return the result. Neither did + calling an instance. .. method:: skipTest(reason) diff --git a/Doc/license.rst b/Doc/license.rst index a32b7abeb6..6c9ecf514a 100644 --- a/Doc/license.rst +++ b/Doc/license.rst @@ -110,6 +110,8 @@ been GPL-compatible; the table below summarizes the various releases. +----------------+--------------+------------+------------+-----------------+ | 3.2 | 3.1 | 2011 | PSF | yes | +----------------+--------------+------------+------------+-----------------+ +| 3.3 | 3.2 | 2012 | PSF | yes | ++----------------+--------------+------------+------------+-----------------+ .. note:: diff --git a/Doc/tools/sphinxext/indexsidebar.html b/Doc/tools/sphinxext/indexsidebar.html index 672492e600..3ad24f9b86 100644 --- a/Doc/tools/sphinxext/indexsidebar.html +++ b/Doc/tools/sphinxext/indexsidebar.html @@ -3,7 +3,7 @@ <h3>Docs for other versions</h3> <ul> <li><a href="http://docs.python.org/2.7/">Python 2.7 (stable)</a></li> - <li><a href="http://docs.python.org/3.1/">Python 3.1 (stable)</a></li> + <li><a href="http://docs.python.org/3.2/">Python 3.2 (stable)</a></li> <li><a href="http://www.python.org/doc/versions/">Old versions</a></li> </ul> diff --git a/Doc/tutorial/classes.rst b/Doc/tutorial/classes.rst index a328ab23a2..3e547a5b6a 100644 --- a/Doc/tutorial/classes.rst +++ b/Doc/tutorial/classes.rst @@ -673,9 +673,9 @@ example, the following code will print B, C, D in that order:: class D(C): pass - for c in [B, C, D]: + for cls in [B, C, D]: try: - raise c() + raise cls() except D: print("D") except C: diff --git a/Doc/tutorial/interpreter.rst b/Doc/tutorial/interpreter.rst index 8d743de34f..eeddf766dd 100644 --- a/Doc/tutorial/interpreter.rst +++ b/Doc/tutorial/interpreter.rst @@ -10,11 +10,11 @@ Using the Python Interpreter Invoking the Interpreter ======================== -The Python interpreter is usually installed as :file:`/usr/local/bin/python3.2` +The Python interpreter is usually installed as :file:`/usr/local/bin/python3.3` 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 :: - python3.2 + python3.3 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 @@ -22,11 +22,11 @@ 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:\\Python32`, though you can change this when you're running the +:file:`C:\\Python33`, 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:\python32 + set path=%path%;C:\python33 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 @@ -94,8 +94,8 @@ 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:: - $ python3.2 - Python 3.2 (py3k, Sep 12 2007, 12:21:02) + $ python3.3 + Python 3.3 (py3k, Sep 12 2007, 12:21:02) [GCC 3.4.6 20060404 (Red Hat 3.4.6-8)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> @@ -148,7 +148,7 @@ 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 python3.2 + #! /usr/bin/env python3.3 (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 diff --git a/Doc/tutorial/stdlib.rst b/Doc/tutorial/stdlib.rst index 97297434ed..500ca7f623 100644 --- a/Doc/tutorial/stdlib.rst +++ b/Doc/tutorial/stdlib.rst @@ -15,7 +15,7 @@ operating system:: >>> import os >>> os.getcwd() # Return the current working directory - 'C:\\Python31' + 'C:\\Python33' >>> os.chdir('/server/accesslogs') # Change current working directory >>> os.system('mkdir today') # Run the command mkdir in the system shell 0 diff --git a/Doc/tutorial/stdlib2.rst b/Doc/tutorial/stdlib2.rst index fe7f027b53..85c88dc23f 100644 --- a/Doc/tutorial/stdlib2.rst +++ b/Doc/tutorial/stdlib2.rst @@ -141,7 +141,9 @@ standard size and in little-endian byte order:: import struct - data = open('myfile.zip', 'rb').read() + with open('myfile.zip', 'rb') as f: + data = f.read() + start = 0 for i in range(3): # show the first 3 file headers start += 14 @@ -271,7 +273,7 @@ applications include caching objects that are expensive to create:: Traceback (most recent call last): File "<stdin>", line 1, in <module> d['primary'] # entry was automatically removed - File "C:/python31/lib/weakref.py", line 46, in __getitem__ + File "C:/python33/lib/weakref.py", line 46, in __getitem__ o = self.data[key]() KeyError: 'primary' diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst index d1f47eba89..72b77cd3b9 100644 --- a/Doc/using/cmdline.rst +++ b/Doc/using/cmdline.rst @@ -239,7 +239,9 @@ Miscellaneous options .. cmdoption:: -S Disable the import of the module :mod:`site` and the site-dependent - manipulations of :data:`sys.path` that it entails. + manipulations of :data:`sys.path` that it entails. Also disable these + manipulations if :mod:`site` is explicitly imported later (call + :func:`site.main` if you want them to be triggered). .. cmdoption:: -u @@ -496,6 +498,14 @@ These environment variables influence Python's behavior. separated string, it is equivalent to specifying :option:`-W` multiple times. +.. envvar:: PYTHONFAULTHANDLER + + If this environment variable is set, :func:`faulthandler.enable` is called + at startup: install a handler for :const:`SIGSEGV`, :const:`SIGFPE`, + :const:`SIGABRT`, :const:`SIGBUS` and :const:`SIGILL` signals to dump the + Python traceback. This is equivalent to :option:`-X` ``faulthandler`` + option. + Debug-mode variables ~~~~~~~~~~~~~~~~~~~~ diff --git a/Doc/using/unix.rst b/Doc/using/unix.rst index 61e707b11c..d065512341 100644 --- a/Doc/using/unix.rst +++ b/Doc/using/unix.rst @@ -66,7 +66,7 @@ Building Python If you want to compile CPython yourself, first thing you should do is get the `source <http://python.org/download/source/>`_. You can download either the latest release's source or just grab a fresh `checkout -<http://www.python.org/dev/faq/#how-do-i-get-a-checkout-of-the-repository-read-only-and-read-write>`_. +<http://docs.python.org/devguide/setup#checking-out-the-code>`_. The build process consists the usual :: diff --git a/Doc/using/windows.rst b/Doc/using/windows.rst index 12378b3233..948753a32e 100644 --- a/Doc/using/windows.rst +++ b/Doc/using/windows.rst @@ -290,7 +290,7 @@ Compiling Python on Windows If you want to compile CPython yourself, first thing you should do is get the `source <http://python.org/download/source/>`_. You can download either the latest release's source or just grab a fresh `checkout -<http://www.python.org/dev/faq/#how-do-i-get-a-checkout-of-the-repository-read-only-and-read-write>`_. +<http://docs.python.org/devguide/setup#checking-out-the-code>`_. For Microsoft Visual C++, which is the compiler with which official Python releases are built, the source tree contains solutions/project files. View the diff --git a/Doc/whatsnew/3.2.rst b/Doc/whatsnew/3.2.rst index d411d85ee8..358e5bec41 100644 --- a/Doc/whatsnew/3.2.rst +++ b/Doc/whatsnew/3.2.rst @@ -270,7 +270,7 @@ launch of four parallel threads for copying files:: e.submit(shutil.copy, 'src1.txt', 'dest1.txt') e.submit(shutil.copy, 'src2.txt', 'dest2.txt') e.submit(shutil.copy, 'src3.txt', 'dest3.txt') - e.submit(shutil.copy, 'src4.txt', 'dest4.txt') + e.submit(shutil.copy, 'src3.txt', 'dest4.txt') .. seealso:: @@ -2354,7 +2354,7 @@ A number of small performance enhancements have been added: (Contributed by Antoine Pitrou; :issue:`3001`.) * The fast-search algorithm in stringlib is now used by the :meth:`split`, - :meth:`splitlines` and :meth:`replace` methods on + :meth:`rsplit`, :meth:`splitlines` and :meth:`replace` methods on :class:`bytes`, :class:`bytearray` and :class:`str` objects. Likewise, the algorithm is also used by :meth:`rfind`, :meth:`rindex`, :meth:`rsplit` and :meth:`rpartition`. @@ -2471,14 +2471,14 @@ Code Repository In addition to the existing Subversion code repository at http://svn.python.org there is now a `Mercurial <http://mercurial.selenic.com/>`_ repository at -http://hg.python.org/\. +http://hg.python.org/ . After the 3.2 release, there are plans to switch to Mercurial as the primary repository. This distributed version control system should make it easier for members of the community to create and share external changesets. See :pep:`385` for details. -To learn the new version control system, see the `tutorial by Joel +To learn to use the new version control system, see the `tutorial by Joel Spolsky <http://hginit.com>`_ or the `Guide to Mercurial Workflows <http://mercurial.selenic.com/guide/>`_. diff --git a/Doc/whatsnew/3.3.rst b/Doc/whatsnew/3.3.rst new file mode 100644 index 0000000000..5d9587d710 --- /dev/null +++ b/Doc/whatsnew/3.3.rst @@ -0,0 +1,170 @@ +**************************** + What's New In Python 3.3 +**************************** + +:Author: Raymond Hettinger +:Release: |release| +:Date: |today| + +.. $Id$ + 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 3.3, compared to 3.2. + + +PEP XXX: Stub +============= + + +Other Language Changes +====================== + +Some smaller changes made to the core Python language are: + +* Stub + + +New, Improved, and Deprecated Modules +===================================== + +* Stub + +faulthandler +------------ + +New module: :mod:`faulthandler`. + + * :envvar:`PYTHONFAULTHANDLER` + * :option:`-X` ``faulthandler`` + +os +-- + +* The :mod:`os` module has a new :func:`~os.sendfile` function which provides + an efficent "zero-copy" way for copying data from one file (or socket) + descriptor to another. The phrase "zero-copy" refers to the fact that all of + the copying of data between the two descriptors is done entirely by the + kernel, with no copying of data into userspace buffers. :func:`~os.sendfile` + can be used to efficiently copy data from a file on disk to a network socket, + e.g. for downloading a file. + + (Patch submitted by Ross Lagerwall and Giampaolo Rodolà in :issue:`10882`.) + +* The :mod:`os` module has two new functions: :func:`~os.getpriority` and + :func:`~os.setpriority`. They can be used to get or set process + niceness/priority in a fashion similar to :func:`os.nice` but extended to all + processes instead of just the current one. + + (Patch submitted by Giampaolo Rodolà in :issue:`10784`.) + +nntplib +------- + +The :class:`nntplib.NNTP` class now supports the context manager protocol to +unconditionally consume :exc:`socket.error` exceptions and to close the NNTP +connection when done:: + + >>> from nntplib import NNTP + >>> with nntplib.NNTP('news.gmane.org') as n: + ... n.group('gmane.comp.python.committers') + ... + ('211 1454 1 1454 gmane.comp.python.committers', '1454', '1', '1454', 'gmane.comp.python.committers') + >>> + +(Contributed by Giampaolo Rodolà in :issue:`9795`) + +sys +--- + +* The :mod:`sys` module has a new :func:`~sys.thread_info` :term:`struct + sequence` holding informations about the thread implementation. + + (:issue:`11223`) + +signal +------ + +* The :mod:`signal` module has a new :func:`~signal.pthread_sigmask` function + to fetch and/or change the signal mask of the calling thread. + + (Contributed by Jean-Paul Calderone in :issue:`8407`) + + +Optimizations +============= + +Major performance enhancements have been added: + +* Stub + + +Build and C API Changes +======================= + +Changes to Python's build process and to the C API include: + +* Stub + + +Unsupported Operating Systems +============================= + +OS/2 and VMS are no more supported because of the lack of a maintainer. + + +Porting to Python 3.3 +===================== + +This section lists previously described changes and other bugfixes +that may require changes to your code: + +* Stub + + +.. Issue #11591: When :program:`python` was started with :option:`-S`, + ``import site`` will not add site-specific paths to the module search + paths. In previous versions, it did. See changeset for doc changes in + various files. Contributed by Carl Meyer with editions by Éric Araujo. + +.. Issue #10998: -Q command-line flags are related artifacts have been + removed. Code checking sys.flags.division_warning will need updating. + Contributed by Éric Araujo. diff --git a/Doc/whatsnew/index.rst b/Doc/whatsnew/index.rst index 8220bd28dd..c60818af45 100644 --- a/Doc/whatsnew/index.rst +++ b/Doc/whatsnew/index.rst @@ -11,6 +11,7 @@ anyone wishing to stay up-to-date after a new release. .. toctree:: :maxdepth: 2 + 3.3.rst 3.2.rst 3.1.rst 3.0.rst |