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<a href="#nested-classes">Classes</a> |
<a href="#func-members">Functions</a> </div>
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<div class="title">Adaptors for pointers to functions</div> </div>
<div class="ingroups"><a class="el" href="a01193.html">Function Objects</a></div></div>
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<h2><a name="nested-classes"></a>
Classes</h2>
<ul>
<li>class <a class="el" href="a00658.html">std::pointer_to_binary_function< _Arg1, _Arg2, _Result ></a>
<dl class="el"><dd class="mdescRight">One of the <a class="el" href="a01198.html">adaptors for function pointers</a>. <a href="a00658.html#details">More...</a><br/></dl><li>class <a class="el" href="a00659.html">std::pointer_to_unary_function< _Arg, _Result ></a>
<dl class="el"><dd class="mdescRight">One of the <a class="el" href="a01198.html">adaptors for function pointers</a>. <a href="a00659.html#details">More...</a><br/></dl></ul>
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Functions</h2>
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<li>template<typename _Arg , typename _Result > pointer_to_unary_function<br class="typebreak"/>
< _Arg, _Result > <a class="el" href="a01198.html#gac7139c6dea6421abef136a026f6c071b">std::ptr_fun</a> (_Result(*__x)(_Arg))
<li>template<typename _Arg1 , typename _Arg2 , typename _Result > pointer_to_binary_function<br class="typebreak"/>
< _Arg1, _Arg2, _Result > <a class="el" href="a01198.html#ga358aa21a20d3e304bbe878f4940f5742">std::ptr_fun</a> (_Result(*__x)(_Arg1, _Arg2))
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<hr/><a name="details" id="details"></a><h2>Detailed Description</h2>
<p>The advantage of function objects over pointers to functions is that the objects in the standard library declare nested typedefs describing their argument and result types with uniform names (e.g., <code>result_type</code> from the base classes <code><a class="el" href="a00723.html">unary_function</a></code> and <code><a class="el" href="a00254.html">binary_function</a></code>). Sometimes those typedefs are required, not just optional.</p>
<p>Adaptors are provided to turn pointers to unary (single-argument) and binary (double-argument) functions into function objects. The long-winded functor <code><a class="el" href="a00659.html" title="One of the adaptors for function pointers.">pointer_to_unary_function</a></code> is constructed with a function pointer <code>f</code>, and its <code>operator()</code> called with argument <code>x</code> returns <code>f(x)</code>. The functor <code><a class="el" href="a00658.html" title="One of the adaptors for function pointers.">pointer_to_binary_function</a></code> does the same thing, but with a double-argument <code>f</code> and <code>operator()</code>.</p>
<p>The function <code>ptr_fun</code> takes a pointer-to-function <code>f</code> and constructs an instance of the appropriate functor. </p>
<hr/><h2>Function Documentation</h2>
<a class="anchor" id="gac7139c6dea6421abef136a026f6c071b"></a><!-- doxytag: member="std::ptr_fun" ref="gac7139c6dea6421abef136a026f6c071b" args="(_Result(*__x)(_Arg))" -->
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template<typename _Arg , typename _Result > </div>
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<td class="memname">pointer_to_unary_function<_Arg, _Result> std::ptr_fun </td>
<td>(</td>
<td class="paramtype">_Result(*)(_Arg) </td>
<td class="paramname"><em>__x</em></td><td>)</td>
<td><code> [inline]</code></td>
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<p>One of the <a class="el" href="a01198.html">adaptors for function pointers</a>. </p>
<p>Definition at line <a class="el" href="a01050_source.html#l00443">443</a> of file <a class="el" href="a01050_source.html">stl_function.h</a>.</p>
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<a class="anchor" id="ga358aa21a20d3e304bbe878f4940f5742"></a><!-- doxytag: member="std::ptr_fun" ref="ga358aa21a20d3e304bbe878f4940f5742" args="(_Result(*__x)(_Arg1, _Arg2))" -->
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template<typename _Arg1 , typename _Arg2 , typename _Result > </div>
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<td class="memname">pointer_to_binary_function<_Arg1, _Arg2, _Result> std::ptr_fun </td>
<td>(</td>
<td class="paramtype">_Result(*)(_Arg1, _Arg2) </td>
<td class="paramname"><em>__x</em></td><td>)</td>
<td><code> [inline]</code></td>
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<p>One of the <a class="el" href="a01198.html">adaptors for function pointers</a>. </p>
<p>Definition at line <a class="el" href="a01050_source.html#l00469">469</a> of file <a class="el" href="a01050_source.html">stl_function.h</a>.</p>
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