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diff --git a/libs/python/doc/v2/implicit.html b/libs/python/doc/v2/implicit.html new file mode 100644 index 000000000..e9d5cac58 --- /dev/null +++ b/libs/python/doc/v2/implicit.html @@ -0,0 +1,163 @@ +<!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/implicit.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/implicit.hpp></h2> + </td> + </tr> + </table> + <hr> + + <h2>Contents</h2> + + <dl class="page-index"> + <dt><a href="#introduction">Introduction</a></dt> + + <dt><a href="#functions">Functions</a></dt> + + <dd> + <dl class="page-index"> + <dt><a href="#implicitly_convertible-spec">Function Template + <code>implicitly_convertible</code></a></dt> + </dl> + </dd> + + <dt><a href="#examples">Example</a></dt> + </dl> + <hr> + + <h2><a name="introduction"></a>Introduction</h2> + <code>implicitly_convertible</code> allows Boost.Python to implicitly + take advantage of a C++ implicit or explicit conversion when matching + Python objects to C++ argument types. + + <h2><a name="functions"></a>Functions</h2> + + <h3><a name="implicitly_convertible-spec"></a>Function template + <code>implicitly_convertible</code></h3> +<pre> +template <class Source, class Target> +void implicitly_convertible(); +</pre> + + <table border="1" summary="implicitly_convertible template parameters"> + <caption> + <b><code>implicitly_convertible</code> template parameters</b><br> + </caption> + + <tr> + <th>Parameter</th> + + <th>Description</th> + </tr> + + <tr> + <td><code>Source</code></td> + + <td>The source type of the implicit conversion</td> + </tr> + + <tr> + <td><code>Target</code></td> + + <td>The target type of the implicit conversion</td> + </tr> + </table> + + <dl class="function-semantics"> + <dt><b>Requires:</b> The declaration <code>Target t(s);</code>, where + <code>s</code> is of type <code>Source</code>, is valid.</dt> + + <dt><b>Effects:</b> registers an rvalue <code>from_python</code> + converter to <code>Target</code> which can succeed for any + <code>PyObject* p</code> iff there exists any registered converter + which can produce <code>Source</code> rvalues</dt> + + <dt><b>Rationale:</b> C++ users expect to be able to take advantage of + the same sort of interoperability in Python as they do in C++.</dt> + </dl> + + <h2><a name="examples"></a>Example</h2> + + <h3>C++ module definition</h3> +<pre> +#include <boost/python/class.hpp> +#include <boost/python/implicit.hpp> +#include <boost/python/module.hpp> + +using namespace boost::python; + +struct X +{ + X(int x) : v(x) {} + operator int() const { return v; } + int v; +}; + +int x_value(X const& x) +{ + return x.v; +} + +X make_x(int n) { return X(n); } + +BOOST_PYTHON_MODULE(implicit_ext) +{ + def("x_value", x_value); + def("make_x", make_x); + + class_<X>("X", + init<int>()) + ; + + implicitly_convertible<X,int>(); + implicitly_convertible<int,X>(); +} +</pre> + + <h3>Python code</h3> +<pre> +>>> from implicit_ext import * +>>> x_value(X(42)) +42 +>>> x_value(42) +42 +>>> x = make_x(X(42)) +>>> x_value(x) +42 +</pre> + + <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> + |