ceph/src/boost/libs/preprocessor/doc/ref/cat.html

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   3         <title>BOOST_PP_CAT</title>
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   8                 The <b>BOOST_PP_CAT</b> macro concatenates its arguments after they have been expanded.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_CAT</b>(<i>a</i>, <i>b</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>a</dt>
  17                         <dd>
  18                                 The left operand of the concatenation.
  19                         </dd>
  20                         <dt>b</dt>
  21                         <dd>
  22                                 The right operand of the concatenation.
  23                         </dd>
  24                 </dl>
  25         <h4>Remarks</h4>
  26                 <div>
  27                         The preprocessor token-pasting operator (<b>##</b>) prevents arguments from expanding.&nbsp;
  28                         This macro allows its arguments to expand before concatenation.
  29                 </div>
  30                 <div>
  31                         Concatenation must not result in an invocation of a macro that uses <b>BOOST_PP_CAT</b>.&nbsp;
  32                         If that happens, <b>BOOST_PP_CAT</b> will not expand the second time.
  33                 </div>
  34 <!-- <h4>See Also</h4> -->
  35         <h4>Requirements</h4>
  36                 <div>
  37                         <b>Header:</b> &nbsp;<a href="../headers/cat.html">&lt;boost/preprocessor/cat.hpp&gt;</a>
  38                 </div>
  39         <h4>Sample Code</h4>
  40 <div><pre>
  41 #include &lt;<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>&gt;
  42
  43 <a href="cat.html">BOOST_PP_CAT</a>(x, <a href="cat.html">BOOST_PP_CAT</a>(y, z)) // expands to xyz
  44 </pre></div>
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  47                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  48                 </br><i>© Copyright Paul Mensonides 2002</i>
  49         </div>
  50         <div style="margin-left: 0px;">
  51                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  52                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  53                 copy at <a href=
  54                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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