ceph/src/boost/libs/type_traits/doc/html/boost_typetraits/reference/is_same.html

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  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_typetraits.reference.is_same"></a><a class="link" href="is_same.html" title="is_same">is_same</a>
  28 </h3></div></div></div>
  29 <pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U</span><span class="special">&gt;</span>
  30 <span class="keyword">struct</span> <span class="identifier">is_same</span> <span class="special">:</span> <span class="keyword">public</span> <em class="replaceable"><code><a class="link" href="integral_constant.html" title="integral_constant">true_type</a>-or-<a class="link" href="integral_constant.html" title="integral_constant">false_type</a></code></em> <span class="special">{};</span>
  31 </pre>
  32 <p>
  33         <span class="bold"><strong>Inherits:</strong></span> If T and U are the same types
  34         then inherits from <a class="link" href="integral_constant.html" title="integral_constant">true_type</a>,
  35         otherwise inherits from <a class="link" href="integral_constant.html" title="integral_constant">false_type</a>.
  36       </p>
  37 <p>
  38         <span class="bold"><strong>Header:</strong></span> <code class="computeroutput"> <span class="preprocessor">#include</span>
  39         <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">/</span><span class="identifier">is_same</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  40         or <code class="computeroutput"> <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  41       </p>
  42 <p>
  43         <span class="bold"><strong>Compiler Compatibility:</strong></span> All current compilers
  44         are supported by this trait.
  45       </p>
  46 <p>
  47         <span class="bold"><strong>Examples:</strong></span>
  48       </p>
  49 <div class="blockquote"><blockquote class="blockquote"><p>
  50           <code class="computeroutput"><span class="identifier">is_same</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">int</span><span class="special">&gt;</span></code> inherits from <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">true_type</a></code>.
  51         </p></blockquote></div>
  52 <div class="blockquote"><blockquote class="blockquote"><p>
  53           <code class="computeroutput"><span class="identifier">is_same</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
  54           is the type <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">true_type</a></code>.
  55         </p></blockquote></div>
  56 <div class="blockquote"><blockquote class="blockquote"><p>
  57           <code class="computeroutput"><span class="identifier">is_same</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">value</span></code>
  58           is an integral constant expression that evaluates to <span class="emphasis"><em>true</em></span>.
  59         </p></blockquote></div>
  60 <div class="blockquote"><blockquote class="blockquote"><p>
  61           <code class="computeroutput"><span class="identifier">is_same</span><span class="special">&lt;</span><span class="keyword">int</span> <span class="keyword">const</span><span class="special">,</span> <span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
  62           that evaluates to <span class="emphasis"><em>false</em></span>.
  63         </p></blockquote></div>
  64 <div class="blockquote"><blockquote class="blockquote"><p>
  65           <code class="computeroutput"><span class="identifier">is_same</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&amp;,</span> <span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
  66           that evaluates to <span class="emphasis"><em>false</em></span>.
  67         </p></blockquote></div>
  68 <div class="blockquote"><blockquote class="blockquote"><p>
  69           <code class="computeroutput"><span class="identifier">is_same</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">,</span> <span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">value_type</span></code>
  70           is the type <code class="computeroutput"><span class="keyword">bool</span></code>.
  71         </p></blockquote></div>
  72 </div>
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  75 <td align="right"><div class="copyright-footer">Copyright &#169; 2000, 2011 Adobe Systems Inc, David Abrahams,
  76       Frederic Bron, Steve Cleary, Beman Dawes, Aleksey Gurtovoy, Howard Hinnant,
  77       Jesse Jones, Mat Marcus, Itay Maman, John Maddock, Alexander Nasonov, Thorsten
  78       Ottosen, Roman Perepelitsa, Robert Ramey, Jeremy Siek, Robert Stewart and Steven
  79       Watanabe<p>
  80         Distributed under the Boost Software License, Version 1.0. (See accompanying
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