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| <boost/python/copy_non_const_reference.hpp></title> |
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| <h1 align="center"><a href="../index.html">Boost.Python</a></h1> |
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| <h2 align="center">Header |
| <boost/python/copy_non_const_reference.hpp></h2> |
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| <h2>Contents</h2> |
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| <dl class="page-index"> |
| <dt><a href="#classes">Classes</a></dt> |
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| <dd> |
| <dl class="page-index"> |
| <dt><a href="#copy_non_const_reference-spec">Class |
| <code>copy_non_const_reference</code></a></dt> |
| |
| <dd> |
| <dl class="page-index"> |
| <dt><a href="#copy_non_const_reference-spec-synopsis">Class |
| <code>copy_non_const_reference</code> synopsis</a></dt> |
| |
| <dt><a href= |
| "#copy_non_const_reference-spec-metafunctions">Class |
| <code>copy_non_const_reference</code> metafunctions</a></dt> |
| </dl> |
| </dd> |
| </dl> |
| </dd> |
| |
| <dt><a href="#examples">Example</a></dt> |
| </dl> |
| <hr> |
| |
| <h2><a name="classes"></a>Classes</h2> |
| |
| <h3><a name="copy_non_const_reference-spec"></a>Class |
| <code>copy_non_const_reference</code></h3> |
| |
| <p><code>copy_non_const_reference</code> is a model of <a href= |
| "ResultConverter.html#ResultConverterGenerator-concept">ResultConverterGenerator</a> |
| which can be used to wrap C++ functions returning a |
| reference-to-non-const type such that the referenced value is copied into |
| a new Python object.</p> |
| |
| <h4><a name="copy_non_const_reference-spec-synopsis"></a>Class |
| <code>copy_non_const_reference</code> synopsis</h4> |
| <pre> |
| namespace boost { namespace python |
| { |
| struct copy_non_const_reference |
| { |
| template <class T> struct apply; |
| }; |
| }} |
| </pre> |
| |
| <h4><a name="copy_non_const_reference-spec-metafunctions"></a>Class |
| <code>copy_non_const_reference</code> metafunctions</h4> |
| <pre> |
| template <class T> struct apply |
| </pre> |
| |
| <dl class="metafunction-semantics"> |
| <dt><b>Requires:</b> <code>T</code> is <code>U&</code> for some |
| non-const <code>U</code>.</dt> |
| |
| <dt><b>Returns:</b> <code>typedef <a href= |
| "to_python_value.html#to_python_value-spec">to_python_value</a><T> |
| type;</code></dt> |
| </dl> |
| |
| <h2><a name="examples"></a>Example</h2> |
| |
| <p>C++ code:</p> |
| <pre> |
| #include <boost/python/module.hpp> |
| #include <boost/python/class.hpp> |
| #include <boost/python/copy_non_const_reference.hpp> |
| #include <boost/python/return_value_policy.hpp> |
| |
| // classes to wrap |
| struct Bar { int x; } |
| |
| struct Foo { |
| Foo(int x) : { b.x = x; } |
| Bar& get_bar() { return b; } |
| private: |
| Bar b; |
| }; |
| |
| // Wrapper code |
| using namespace boost::python; |
| BOOST_PYTHON_MODULE(my_module) |
| { |
| class_<Bar>("Bar"); |
| |
| class_<Foo>("Foo", init<int>()) |
| .def("get_bar", &Foo::get_bar |
| , return_value_policy<copy_non_const_reference>()) |
| ; |
| } |
| </pre> |
| Python Code: |
| <pre> |
| >>> from my_module import * |
| >>> f = Foo(3) # create a Foo object |
| >>> b = f.get_bar() # make a copy of the internal Bar object |
| </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> |
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