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| <h3><a href="../../../../index.htm"><img height="86" width="277" alt= |
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| <h1 align="center"><a href="../index.html">Boost.Python</a></h1> |
| <h2 align="center">Header <call.hpp></h2> |
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| <hr> |
| <h2>Contents</h2> |
| <dl class="page-index"> |
| <dt><a href="#introduction">Introduction</a></dt> |
| <dt><a href="#functions">Functions</a></dt> |
| <dl class="page-index"> |
| <dt><a href="#call-spec">call</a></dt> |
| </dl> |
| |
| <dt><a href="#examples">Example(s)</a></dt> |
| |
| </dl> |
| <hr> |
| <h2><a name="introduction"></a>Introduction</h2> |
| <p> |
| <code><boost/python/call.hpp></code> defines the <a |
| href="#call-spec"><code>call</code></a> family of overloaded function |
| templates, used to invoke Python callable objects from C++. |
| |
| <h2><a name="functions"></a>Functions</h2> |
| <pre> |
| <a name="call-spec">template <class R, class A1, class A2, ... class A<i>n</i>></a> |
| R call(PyObject* callable, A1 const&, A2 const&, ... A<i>n</i> const&) |
| </pre> |
| <dl class="function-semantics"> |
| <dt><b>Requires:</b> <code>R</code> is a pointer type, reference |
| type, or a complete type with an accessible copy constructor</dt> |
| |
| <dt><b>Effects:</b> Invokes <code>callable(a1, a2, ...a<i>n</i>)</code> in |
| Python, where <code>a1</code>...<code>a<i>n</i></code> are the arguments to |
| <code>call()</code>, converted to Python objects. |
| <dt><b>Returns:</b> The result of the Python call, converted to the C++ type <code>R</code>.</dt> |
| |
| </dt> |
| <dt><b>Rationale:</b> For a complete semantic description and |
| rationale, see <a href="callbacks.html">this page</a>. |
| </dt> |
| </dl> |
| |
| <h2><a name="examples"></a>Example(s)</h2> |
| |
| The following C++ function applies a Python callable object to its two |
| arguments and returns the result. If a Python exception is raised or |
| the result can't be converted to a <code>double</code>, an exception |
| is thrown. |
| |
| <pre> |
| double apply2(PyObject* func, double x, double y) |
| { |
| return boost::python::call<double>(func, x, y); |
| } |
| </pre> |
| |
| <p>Revised |
| <!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan --> |
| 9 May, 2002 <!-- Luann's birthday! --> |
| <!--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> |
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