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

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   3         <title>BOOST_PP_SUB</title>
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   8                 The <b>BOOST_PP_SUB</b> macro expands to the difference between its arguments.
   9         </div>
  10         <h4>Usage</h4>
  11                 <div class="code">
  12                         <b>BOOST_PP_SUB</b>(<i>x</i>, <i>y</i>)
  13                 </div>
  14         <h4>Arguments</h4>
  15                 <dl>
  16                         <dt>x</dt>
  17                         <dd>
  18                                 The minuend of the operation.&nbsp;
  19                                 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
  20                         </dd>
  21                         <dt>y</dt>
  22                         <dd>
  23                                 The subtrahend of the operation.&nbsp;
  24                                 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
  25                         </dd>
  26                 </dl>
  27         <h4>Remarks</h4>
  28                 <div>
  29                         If the difference between <i>x</i> and <i>y</i> is less than <i>0</i>, the result is saturated to <i>0</i>.
  30                 </div>
  31                 <div>
  32                         Previously, this macro could not be used inside <b>BOOST_PP_WHILE</b>.&nbsp;
  33                         There is no longer any such restriction.&nbsp;
  34                         It is more efficient, however, to use <b>BOOST_PP_SUB_D</b> in such a situation.
  35                 </div>
  36         <h4>See Also</h4>
  37                 <ul>
  38                         <li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
  39                         <li><a href="sub_d.html">BOOST_PP_SUB_D</a></li>
  40                 </ul>
  41         <h4>Requirements</h4>
  42                 <div>
  43                         <b>Header:</b> &nbsp;<a href="../headers/arithmetic/sub.html">&lt;boost/preprocessor/arithmetic/sub.hpp&gt;</a>
  44                 </div>
  45         <h4>Sample Code</h4>
  46 <div><pre>
  47 #include &lt;<a href="../headers/arithmetic/sub.html">boost/preprocessor/arithmetic/sub.hpp</a>&gt;
  48
  49 <a href="sub.html">BOOST_PP_SUB</a>(4, 3) // expands to 1
  50 </pre></div>
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  53                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  54                 </br><i>© Copyright Paul Mensonides 2002</i>
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  57                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  58                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  59                 copy at <a href=
  60                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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