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diff --git a/libs/python/doc/v2/iterator.html b/libs/python/doc/v2/iterator.html new file mode 100644 index 000000000..3557ffb9a --- /dev/null +++ b/libs/python/doc/v2/iterator.html @@ -0,0 +1,398 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> + +<!-- Copyright David Abrahams 2006. Distributed under the Boost --> +<!-- Software License, Version 1.0. (See accompanying --> +<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> +<html> + <head> + <meta name="generator" content= + "HTML Tidy for Windows (vers 1st August 2002), see www.w3.org"> + <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> + <link rel="stylesheet" type="text/css" href="../boost.css"> + + <title>Boost.Python - <boost/python/iterator.hpp></title> + </head> + + <body> + <table border="0" cellpadding="7" cellspacing="0" width="100%" summary= + "header"> + <tr> + <td valign="top" width="300"> + <h3><a href="../../../../index.htm"><img height="86" width="277" + alt="C++ Boost" src="../../../../boost.png" border="0"></a></h3> + </td> + + <td valign="top"> + <h1 align="center"><a href="../index.html">Boost.Python</a></h1> + + <h2 align="center">Header <boost/python/iterator.hpp></h2> + </td> + </tr> + </table> + <hr> + + <h2>Contents</h2> + + <dl class="page-index"> + <dt><a href="#introduction">Introduction</a></dt> + + <dt><a href="#classes">Classes</a></dt> + + <dd> + <dl class="page-index"> + <dt><a href="#iterator-spec">Class template + <code>iterator</code></a></dt> + + <dd> + <dl class="page-index"> + <dt><a href="#iterator-spec-synopsis">Class + <code>iterator</code> synopsis</a></dt> + + <dt><a href="#iterator-spec-constructors">Class template + <code>iterator</code> constructor</a></dt> + </dl> + </dd> + </dl> + + <dl class="page-index"> + <dt><a href="#iterators-spec">Class template + <code>iterators</code></a></dt> + + <dd> + <dl class="page-index"> + <dt><a href="#iterators-spec-synopsis">Class + <code>iterators</code> synopsis</a></dt> + + <dt><a href="#iterators-spec-types">Class template + <code>iterators</code> nested types</a></dt> + + <dt><a href="#iterators-spec-statics">Class template + <code>iterators</code> static functions</a></dt> + </dl> + </dd> + </dl> + </dd> + + <dt><a href="#functions">Functions</a></dt> + + <dd> + <dl class="page-index"> + <dt><a href="#range-spec">range</a></dt> + </dl> + </dd> + + <dt><a href="#examples">Examples</a></dt> + </dl> + <hr> + + <h2><a name="introduction"></a>Introduction</h2> + + <p><code><boost/python/iterator.hpp></code> provides types and + functions for creating <a href= + "http://www.python.org/doc/current/lib/typeiter.html">Python + iterators</a> from <a href= + "http://www.sgi.com/tech/stl/Container.html">C++ Containers</a> and <a + href="http://www.sgi.com/tech/stl/Iterators.html">Iterators</a>. Note + that if your <code>class_</code> supports random-access iterators, + implementing <code><a href= + "http://www.python.org/doc/current/ref/sequence-types.html#l2h-128">__getitem__</a></code> + (also known as the Sequence Protocol) may serve you better than using + this facility: Python will automatically create an iterator type for you + (see <a href= + "http://www.python.org/doc/current/lib/built-in-funcs.html#l2h-35">iter()</a>), + and each access can be range-checked, leaving no possiblity of accessing + through an invalidated C++ iterator.</p> + + <h2><a name="classes"></a>Classes</h2> + + <h3><a name="iterator-spec"></a>Class Template <code>iterator</code></h3> + + <p>Instances of <code>iterator<C,P></code> hold a reference to a + callable Python object which, when invoked from Python, expects a single + argument <code>c</code> convertible to <code>C</code> and creates a + Python iterator that traverses [<code>c.begin()</code>, + <code>c.end()</code>). The optional <a href= + "CallPolicies.html">CallPolicies</a> <code>P</code> can be used to + control how elements are returned during iteration.</p> + + <p>In the table below, <code><b>c</b></code> is an instance of + <code>Container</code>.</p> + + <table border="1" summary="iterator template parameters"> + <tr> + <th>Template Parameter</th> + + <th>Requirements</th> + + <th>Semantics</th> + + <th>Default</th> + </tr> + + <tr> + <td><code>Container</code></td> + + <td>[c.begin(),c.end()) is a valid <a href= + "http://www.sgi.com/tech/stl/Iterators.html">Iterator range</a>.</td> + + <td>The result will convert its argument to <code>c</code> and call + <code>c.begin()</code> and <code>c.end()</code> to acquire iterators. + To invoke <code>Container</code>'s <code>const</code> + <code>begin()</code> and <code>end()</code> functions, make it + <code>const</code>.</td> + </tr> + + <tr> + <td><code>NextPolicies</code></td> + + <td>A default-constructible model of <a href= + "CallPolicies.html#CallPolicies-concept">CallPolicies</a>.</td> + + <td>Applied to the resulting iterators' <code>next()</code> + method.</td> + + <td>An unspecified model of <a href= + "CallPolicies.html#CallPolicies-concept">CallPolicies</a> which + always makes a copy of the result of deferencing the underlying C++ + iterator</td> + </tr> + </table> + + <h4><a name="iterator-spec-synopsis"></a>Class Template iterator + synopsis</h4> +<pre> +namespace boost { namespace python +{ + template <class Container + , class NextPolicies = <i>unspecified</i>> + struct iterator : <a href="object.html#object-spec">object</a> + { + iterator(); + }; +}} +</pre> + + <h4><a name="iterator-spec-constructors"></a>Class Template iterator + constructor</h4> +<pre> +iterator() +</pre> + + <dl class="function-semantics"> + <dt><b>Effects:</b></dt> + + <dd> + Initializes its base class with the result of: +<pre> +range<NextPolicies>(&iterators<Container>::begin, &iterators<Container>::end) +</pre> + </dd> + + <dt><b>Postconditions:</b> <code>this->get()</code> points to a + Python callable object which creates a Python iterator as described + above.</dt> + + <dt><b>Rationale:</b> Provides an easy way to create iterators for the + common case where a C++ class being wrapped provides + <code>begin()</code> and <code>end()</code>.</dt> + </dl> + <!-- --> + + <h3><a name="iterators-spec"></a>Class Template + <code>iterators</code></h3> + + <p>A utility class template which provides a way to reliably call its + argument's <code>begin()</code> and <code>end()</code> member functions. + Note that there is no portable way to take the address of a member + function of a C++ standard library container, so + <code>iterators<></code> can be particularly helpful when wrapping + them.</p> + + <p>In the table below, <code><b>x</b></code> is an instance of + <code>C</code>.</p> + + <table border="1" summary="iterator template parameters"> + <tr> + <th>Required Valid Expression</th> + + <th>Type</th> + </tr> + + <tr> + <td><code>x.begin()</code></td> + + <td>Convertible to <code>C::const_iterator</code> if <code>C</code> + is a <code>const</code> type; convertible to <code>C::iterator</code> + otherwise.</td> + </tr> + + <tr> + <td><code>x.end()</code></td> + + <td>Convertible to <code>C::const_iterator</code> if <code>C</code> + is a <code>const</code> type; convertible to <code>C::iterator</code> + otherwise.</td> + </tr> + </table> + + <h4><a name="iterators-spec-synopsis"></a>Class Template iterators + synopsis</h4> +<pre> +namespace boost { namespace python +{ + template <class C> + struct iterators + { + typedef typename C::[const_]iterator iterator; + static iterator begin(C& x); + static iterator end(C& x); + }; +}} + +</pre> + + <h4><a name="iterators-spec-types"></a>Class Template iterators nested + types</h4> + If C is a <code>const</code> type, +<pre> +typedef typename C::const_iterator iterator; +</pre> + Otherwise: +<pre> +typedef typename C::iterator iterator; +</pre> + + <h4><a name="iterators-spec-statics"></a>Class Template iterators static + functions</h4> +<pre> +static iterator begin(C&); +</pre> + + <dl class="function-semantics"> + <dt><b>Returns:</b> <code>x.begin()</code></dt> + </dl> +<pre> +static iterator end(C&); +</pre> + + <dl class="function-semantics"> + <dt><b>Returns:</b> <code>x.end()</code></dt> + </dl> + <!-- --> + + <h2><a name="functions"></a>Functions</h2> +<pre> +<a name= +"range-spec">template</a> <class NextPolicies, class Target, class Accessor1, class Accessor2> +<a href= +"object.html#object-spec">object</a> range(Accessor1 start, Accessor2 finish); + +template <class NextPolicies, class Accessor1, class Accessor2> +<a href= +"object.html#object-spec">object</a> range(Accessor1 start, Accessor2 finish); + +template <class Accessor1, class Accessor2> +<a href= +"object.html#object-spec">object</a> range(Accessor1 start, Accessor2 finish); +</pre> + + <dl class="range-semantics"> + <dt><b>Requires:</b> <code>NextPolicies</code> is a + default-constructible model of <a href= + "CallPolicies.html#CallPolicies-concept">CallPolicies</a>.</dt> + + <dt><b>Effects:</b></dt> + + <dd> + <dl> + <dt>The first form creates a Python callable object which, when + invoked, converts its argument to a <code>Target</code> object + <code>x</code>, and creates a Python iterator which traverses + [<code><a href= + "../../../bind/bind.html">bind</a>(start,_1)(x)</code>, <code><a + href="../../../bind/bind.html">bind</a>(finish,_1)(x)</code>), + applying <code>NextPolicies</code> to the iterator's + <code>next()</code> function.</dt> + + <dt>The second form is identical to the first, except that + <code>Target</code> is deduced from <code>Accessor1</code> as + follows:</dt> + + <dd> + <ol> + <li>If <code>Accessor1</code> is a function type, + <code>Target</code> is the type of its first argument.</li> + + <li>If <code>Accessor1</code> is a data member pointer of the + form <code>R (T::*)</code>, <code>Target</code> is + identical to <code>T</code>.</li> + + <li>If <code>Accessor1</code> is a member function pointer of + the form + <code>R (T::*)(</code><i>arguments...</i><code>)</code> + <i>cv-opt</i>, where <i>cv-opt</i> is an optional + <code>cv-qualifier</code>, <code>Target</code> is identical to + <code>T</code>.</li> + </ol> + </dd> + + <dt>The third form is identical to the second, except that + <code>NextPolicies</code> is an unspecified model of <a href= + "CallPolicies.html#CallPolicies-concept">CallPolicies</a> which + always makes a copy of the result of deferencing the underlying C++ + iterator</dt> + </dl> + </dd> + + <dt><b>Rationale:</b> The use of <code><a href= + "../../../bind/bind.html">boost::bind</a>()</code> allows C++ iterators + to be accessed through functions, member functions or data member + pointers. Customization of <code>NextPolicies</code> (e.g. using + <code><a href= + "return_internal_reference.html#return_internal_reference-spec">return_internal_reference</a></code>) + is useful when it is expensive to copy sequence elements of a wrapped + class type. Customization of <code>Target</code> is useful when + <code>Accessor1</code> is a function object, or when a base class of + the intended target type would otherwise be deduced.</dt> + </dl> + + <h2><a name="examples"></a>Examples</h2> +<pre> +#include <boost/python/module.hpp> +#include <boost/python/class.hpp> + +#include <vector> + +using namespace boost::python; +BOOST_PYTHON_MODULE(demo) +{ + class_<std::vector<double> >("dvec") + .def("__iter__", iterator<std::vector<double> >()) + ; +} +</pre> + A more comprehensive example can be found in: + + <dl> + <dt><code><a href= + "../../test/iterator.cpp">libs/python/test/iterator.cpp</a></code></dt> + + <dt><code><a href= + "../../test/input_iterator.cpp">libs/python/test/input_iterator.cpp</a></code></dt> + + <dt><code><a href= + "../../test/iterator.py">libs/python/test/input_iterator.py</a></code></dt> + + </dl> +<hr> + <p>Revised + <!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan --> + 13 November, 2002 + <!--webbot bot="Timestamp" endspan i-checksum="39359" --> + </p> + + <p><i>© Copyright <a href= + "http://www.boost.org/people/dave_abrahams.htm">Dave Abrahams</a> 2002.</i></p> + </body> +</html> + |