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updated boost from 1_33_1 to 1_34_1
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1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2
3<!-- Copyright David Abrahams 2006. Distributed under the Boost -->
4<!-- Software License, Version 1.0. (See accompanying -->
5<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
6<html>
7  <head>
8    <meta name="generator" content=
9    "HTML Tidy for Cygwin (vers 1st April 2002), see www.w3.org">
10    <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
11    <link rel="stylesheet" type="text/css" href="../boost.css">
12
13    <title>Boost.Python - &lt;boost/python/def.hpp&gt;</title>
14  </head>
15
16  <body>
17    <table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
18    "header">
19      <tr>
20        <td valign="top" width="300">
21          <h3><a href="../../../../index.htm"><img height="86" width="277"
22          alt="C++ Boost" src="../../../../boost.png" border="0"></a></h3>
23        </td>
24
25        <td valign="top">
26          <h1 align="center"><a href="../index.html">Boost.Python</a></h1>
27
28          <h2 align="center">Header &lt;boost/python/def.hpp&gt;</h2>
29        </td>
30      </tr>
31    </table>
32    <hr>
33
34    <h2>Contents</h2>
35
36    <dl class="page-index">
37      <dt><a href="#introduction">Introduction</a></dt>
38
39      <dt><a href="#functions">Functions</a></dt>
40
41      <dd>
42        <dl class="page-index">
43          <dt><a href="#def-spec">def</a></dt>
44        </dl>
45      </dd>
46
47      <dt><a href="#examples">Example</a></dt>
48    </dl>
49    <hr>
50
51    <h2><a name="introduction"></a>Introduction</h2>
52
53    <p><code><a href="#def-spec">def</a>()</code> is the function which can
54    be used to expose C++ functions and callable objects as Python functions
55    in the current <code><a href="scope.html">scope</a></code>.</p>
56
57    <h2><a name="functions"></a>Functions</h2>
58    <a name="def-spec"></a>def
59<pre>
60template &lt;class F&gt;
61void def(char const* name, F f);
62
63template &lt;class Fn, class A1&gt;
64void def(char const* name, Fn fn, A1 const&amp;);
65
66template &lt;class Fn, class A1, class A2&gt;
67void def(char const* name, Fn fn, A1 const&amp;, A2 const&amp;);
68
69template &lt;class Fn, class A1, class A2, class A3&gt;
70void def(char const* name, Fn fn, A1 const&amp;, A2 const&amp;, A3 const&amp;);
71</pre>
72
73    <dl class="function-semantics">
74      <dt><b>Requires:</b> <code>name</code> is an <a href=
75      "definitions.html#ntbs">ntbs</a> which conforms to Python's <a href=
76      "http://www.python.org/doc/current/ref/identifiers.html">identifier
77      naming rules</a>.</dt>
78
79      <dd>
80        <ul>
81          <li>If <code>Fn</code> is [derived from] <code><a href=
82          "object.html#object-spec">object</a></code>, it will be added to
83          the current scope as a single overload. To be useful,
84          <code>fn</code> should be <a href=
85          "http://www.python.org/doc/current/lib/built-in-funcs.html#l2h-6">callable</a>.</li>
86
87          <li>
88            If <code>a1</code> is the result of an <a href=
89            "overloads.html#overload-dispatch-expression"><em>overload-dispatch-expression</em></a>,
90            only the second form is allowed and fn must be a pointer to
91            function or pointer to member function whose <a href=
92            "definitions.html#arity">arity</a> is the same as A1's <a href=
93            "overloads.html#overload-dispatch-expression"><em>maximum
94            arity</em></a>.
95
96            <dl>
97              <dt><b>Effects:</b> For each prefix <em>P</em> of
98              <code>Fn</code>'s sequence of argument types, beginning with
99              the one whose length is <code>A1</code>'s <a href=
100              "overloads.html#overload-dispatch-expression"><em>minimum
101              arity</em></a>, adds a
102              <code><em>name</em>(</code>...<code>)</code> function overload
103              to the <a href="scope.html">current scope</a>. Each overload
104              generated invokes <code>a1</code>'s call-expression with
105              <em>P</em>, using a copy of <code>a1</code>'s <a href=
106              "CallPolicies.html">call policies</a>. If the longest valid
107              prefix of <code>A1</code> contains <em>N</em> types and
108              <code>a1</code> holds <em>M</em> keywords, an initial sequence
109              of the keywords are used for all but the first
110              <em>N</em>&nbsp;-&nbsp;<em>M</em> arguments of each
111              overload.<br>
112              </dt>
113            </dl>
114          </li>
115
116          <li>Otherwise, fn must be a non-null function or member function
117          pointer, and a single function overload built around fn is added to
118          the <a href="scope.html">current scope</a>. If any of
119          <code>a1</code>-<code>a3</code> are supplied, they may be selected
120          in any order from the table below.</li>
121        </ul>
122
123        <table border="1" summary="def() optional arguments">
124          <tr>
125            <th>Memnonic Name</th>
126
127            <th>Requirements/Type properties</th>
128
129            <th>Effects</th>
130          </tr>
131
132          <tr>
133            <td>docstring</td>
134
135            <td>Any <a href="definitions.html#ntbs">ntbs</a>.</td>
136
137            <td>Value will be bound to the <code>__doc__</code> attribute of
138            the resulting method overload.</td>
139          </tr>
140
141          <tr>
142            <td>policies</td>
143
144            <td>A model of <a href="CallPolicies.html">CallPolicies</a></td>
145
146            <td>A copy will be used as the call policies of the resulting
147            method overload.</td>
148          </tr>
149
150          <tr>
151            <td>keywords</td>
152
153            <td>The result of a <a href=
154            "args.html#keyword-expression"><em>keyword-expression</em></a>
155            specifying no more arguments than the <a href=
156            "definitions.html#arity">arity</a> of <code>fn</code>.</td>
157
158            <td>A copy will be used as the call policies of the resulting
159            method overload.</td>
160          </tr>
161        </table>
162      </dd>
163    </dl>
164
165    <h2><a name="examples"></a>Example</h2>
166<pre>
167#include &lt;boost/python/def.hpp&gt;
168#include &lt;boost/python/module.hpp&gt;
169#include &lt;boost/python/args.hpp&gt;
170
171using namespace boost::python;
172
173char const* foo(int x, int y) { return "foo"; }
174
175BOOST_PYTHON_MODULE(def_test)
176{
177    def("foo", foo, args("x", "y"), "foo's docstring");
178}
179</pre>
180
181    <p>
182    <!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
183     7 March, 2003
184    <!--webbot bot="Timestamp" endspan i-checksum="39359" -->
185    </p>
186
187    <p><i>&copy; Copyright <a href=
188    "../../../../people/dave_abrahams.htm">Dave Abrahams</a> 2002.</i></p>
189  </body>
190</html>
191
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