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  26 <a name="boost.any_cast_idp41191712"></a><div class="titlepage"></div>
  27 <div class="refnamediv">
  28 <h2><span class="refentrytitle">Function any_cast</span></h2>
  29 <p>boost::any_cast &#8212; Custom keyword cast for extracting a value
  30           of a given type from an
  31           <code class="computeroutput"><a class="link" href="any.html" title="Class any">any</a></code>.</p>
  32 </div>
  33 <h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
  34 <div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../any/reference.html#header.boost.any_hpp" title="Header &lt;boost/any.hpp&gt;">boost/any.hpp</a>&gt;
  35
  36 </span>
  37 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> <span class="identifier">T</span> <span class="identifier">any_cast</span><span class="special">(</span><a class="link" href="any.html" title="Class any">any</a> <span class="special">&amp;</span> operand<span class="special">)</span><span class="special">;</span>
  38 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> <span class="identifier">T</span> <span class="identifier">any_cast</span><span class="special">(</span><a class="link" href="any.html" title="Class any">any</a> <span class="special">&amp;&amp;</span> operand<span class="special">)</span><span class="special">;</span>
  39 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> <span class="identifier">T</span> <span class="identifier">any_cast</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="any.html" title="Class any">any</a> <span class="special">&amp;</span> operand<span class="special">)</span><span class="special">;</span>
  40 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> ValueType<span class="special">&gt;</span> <span class="keyword">const</span> <span class="identifier">ValueType</span> <span class="special">*</span> <span class="identifier">any_cast</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="any.html" title="Class any">any</a> <span class="special">*</span> operand<span class="special">)</span><span class="special">;</span>
  41 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> ValueType<span class="special">&gt;</span> <span class="identifier">ValueType</span> <span class="special">*</span> <span class="identifier">any_cast</span><span class="special">(</span><a class="link" href="any.html" title="Class any">any</a> <span class="special">*</span> operand<span class="special">)</span><span class="special">;</span></pre></div>
  42 <div class="refsect1">
  43 <a name="idp121292224"></a><h2>Description</h2>
  44 <div class="variablelist"><table border="0" class="variablelist compact">
  45 <colgroup>
  46 <col align="left" valign="top">
  47 <col>
  48 </colgroup>
  49 <tbody>
  50 <tr>
  51 <td><p><span class="term">Returns:</span></p></td>
  52 <td> If passed a pointer, it returns a
  53           similarly qualified pointer to the value content if
  54           successful, otherwise null is returned.
  55           If T is ValueType, it returns a copy of the held value, otherwise, if T is a reference
  56           to (possibly const qualified) ValueType, it returns a reference to the held
  57           value.</td>
  58 </tr>
  59 <tr>
  60 <td><p><span class="term">Throws:</span></p></td>
  61 <td>Overloads taking an
  62           <code class="computeroutput"><a class="link" href="any.html" title="Class any">any</a></code> pointer do not
  63           throw; overloads taking an
  64           <code class="computeroutput"><a class="link" href="any.html" title="Class any">any</a></code> value or reference
  65           throws <code class="computeroutput"><a class="link" href="bad_any_cast.html" title="Class bad_any_cast">bad_any_cast</a></code> if
  66           unsuccessful.</td>
  67 </tr>
  68 </tbody>
  69 </table></div>
  70 </div>
  71 </div>
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  73 <td align="left"></td>
  74 <td align="right"><div class="copyright-footer">Copyright &#169; 2001 Kevlin Henney<p>Distributed under the Boost Software License, Version 1.0.
  75       (See accompanying file <code class="filename">LICENSE_1_0.txt</code> or copy at
  76       <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
  77       </p>
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