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

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   3         <title>BOOST_PP_DIV_D</title>
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   8                 The <b>BOOST_PP_DIV_D</b> macro expands to the quotient of its second and third arguments.&nbsp;
   9                 It reenters <b>BOOST_PP_WHILE</b> with maximum efficiency.
  10         </div>
  11         <h4>Usage</h4>
  12                 <div class="code">
  13                         <b>BOOST_PP_DIV_D</b>(<i>d</i>, <i>x</i>, <i>y</i>)
  14                 </div>
  15         <h4>Arguments</h4>
  16                 <dl>
  17                         <dt>d</dt>
  18                         <dd>
  19                                 The next available <b>BOOST_PP_WHILE</b> iteration.&nbsp;
  20                         </dd>
  21                         <dt>x</dt>
  22                         <dd>
  23                                 The dividend (numerator) of the operation.&nbsp;
  24                                 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
  25                         </dd>
  26                         <dt>y</dt>
  27                         <dd>
  28                                 The divisor (denominator) of the operation.&nbsp;
  29                                 Valid values range from <i>1</i> to <b>BOOST_PP_LIMIT_MAG</b>.
  30                         </dd>
  31                 </dl>
  32         <h4>Remarks</h4>
  33                 <div>
  34                         If <i>y</i> is <i>0</i>, the result is undefined.
  35                 </div>
  36         <h4>See Also</h4>
  37                 <ul>
  38                         <li><a href="div.html">BOOST_PP_DIV</a></li>
  39                         <li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
  40                 </ul>
  41         <h4>Requirements</h4>
  42                 <div>
  43                         <b>Header:</b> &nbsp;<a href="../headers/arithmetic/div.html">&lt;boost/preprocessor/arithmetic/div.hpp&gt;</a>
  44                 </div>
  45         <h4>Sample Code</h4>
  46 <div><pre>
  47 #include &lt;<a href="../headers/arithmetic/dec.html">boost/preprocessor/arithmetic/dec.hpp</a>&gt;
  48 #include &lt;<a href="../headers/arithmetic/div.html">boost/preprocessor/arithmetic/div.hpp</a>&gt;
  49 #include &lt;<a href="../headers/control/while.html">boost/preprocessor/control/while.hpp</a>&gt;
  50 #include &lt;<a href="../headers/tuple/elem.html">boost/preprocessor/tuple/elem.hpp</a>&gt;
  51
  52 #define PRED(d, data) <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 0, data)
  53
  54 #define OP(d, data) \
  55    ( \
  56       <a href="dec.html">BOOST_PP_DEC</a>( \
  57          <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 0, data) \
  58       ), \
  59       <a href="div_d.html">BOOST_PP_DIV_D</a>( \
  60          d, \
  61          <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 1, data), \
  62          2 \
  63       ) \
  64    ) \
  65    /**/
  66
  67 // halve 'x' 'n' times
  68 #define HALVE(x, n) <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 1, <a href="while.html">BOOST_PP_WHILE</a>(PRED, OP, (n, x)))
  69
  70 HALVE(8, 2) // expands to 2
  71 HALVE(16, 1) // expands to 8
  72 </pre></div>
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  75                 <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
  76                 </br><i>© Copyright Paul Mensonides 2002</i>
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  79                 <p><small>Distributed under the Boost Software License, Version 1.0. (See
  80                 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  81                 copy at <a href=
  82                 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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